The GaCl3-Catalyzed Knoevenagel Condensation To Achieve Acceptor-Donor-Acceptor Small-Molecule Acceptors: A DFT Mechanistic Study.

Herein, the reaction mechanism for the GaCl3-catalyzed Knoevenagel condensation of 2-formylindacenodithieno[3,2-b]thiophene (ITIC-CHO) and active methylene compound 1,1-dicyanomethylene-3-indanone (IC) to synthesize ITIC in the presence of acetic anhydride was investigated using the density functional theory (DFT) method. The calculated results indicate that this reaction follows a bimolecular GaCl3 catalytic mechanism. The free energy span for the monomolecular GaCl3 catalytic mechanism is the highest (31.8 kcal/mol), followed by the trimolecular GaCl3 catalytic mechanism (26.4 kcal/mol) and the bimolecular GaCl3 catalytic mechanism (26.3 kcal/mol). The trimolecular GaCl3 path and bimolecular GaCl3 path are competitive, but the former path is limited by the concentration of GaCl3. The inclusion of GaCl3 could stabilize the transition states of C-H activation. Compared to the GaCl3-catalyzed Knoevenagel condensation, that catalyzed by pyridine is not advantageous, owning a high energy span of 31.7 kcal/mol. These agree well with experimental results. This work could provide a novel theoretical understanding of the Knoevenagel condensation, which could inspire the development of a synthesis strategy for electron acceptor materials.

Value of hepatic artery digital subtraction angiography in the detection of small hepatocellular carcinoma lesions.

OBJECTIVE: To compare the detection rates of hepatic artery digital subtraction angiography (HA-DSA) and magnetic resonance imaging (MRI) gadolinium diethylenetriaminepentaacetic acid (MRI-Gd-DTPA) and MRI gadolinium diethylenetriaminepentaacetic acid (MRI-Gd-EOB-DTPA) for small (diameter ≤2 cm) hepatocellular carcinoma (HCC) lesions. METHODS: A prospective analysis of patients admitted to the Tumor Hospital of Guangxi Medical University between January 1, 2015, and December 30, 2016, was conducted. The detection rates of the three methods were analyzed. The diameter of small HCC lesions detected using HA-DSA and MRI-Gd-EOB-DTPA were evaluated. The diagnostic value of HCC Barcelona staging for HA-DSA was analyzed. RESULTS: For 107 small lesions detected in 57 patients, the detection rates of HA-DSA and MRI-Gd-DTPA were 86.0% (92/107) and 71.0% (76/107), respectively (p < .05). Of 77 small lesions detected in 42 patients using MRI-Gd-EOB-DTPA and HA-DSA, 67 were detected using HA-DSA, all of which had a rich blood supply, and 72 were detected using MRI-Gd-EOB-DTPA. The minimum diameter of lesions detected using MRI-Gd-EOB-DTPA was approximately 0.4 cm, whereas that of lesions detected using HA-DSA was approximately 0.5 cm. After HA-DSA, a change in the Barcelona staging occurred in 33.3% (62/186) of cases but not after MRI-Gd-DTPA; HA-DSA was significantly better than MRI-Gd-DTPA for staging (p = .03). CONCLUSION: HA-DSA and MRI-Gd-EOB-DTPA have high diagnostic values for the detection of small HCC lesions, which is helpful for accurate staging of HCC and provides the most valuable information for patient treatment and prognosis.

Tethered Trimeric Small-molecular Acceptors through Aromatic-core Engineering for Highly Efficient and Thermally Stable Polymer Solar Cells.

Polymer solar cells (PSCs) rely on a blend of small molecular acceptors (SMAs) with polymer donors, where thermodynamic relaxation of SMAs poses critical concerns on operational stability. To tackle this issue, tethered SMAs, wherein multiple SMA-subunits are connected to the aromatic-core via flexible chains, are proposed. This design aims to an elevated glass transition temperature (Tg) for a dynamical control. However, attaining an elevated Tg value with additional SMA subunits introduces complexity to the molecular packing, posing a significant challenge in realizing both high stability and power conversion efficiency (PCE). In this study, we initiate isomer engineering on the benzene-carboxylate core and find that meta-positioned dimeric BDY-ß exhibits more favorable molecular packing compared to its para-positioned counterpart, BDY-α. With this encouraging result, we expand our approach by introducing an additional SMA unit onto the aromatic core of BDY-ß, maintaining a meta-position relative to each SMA unit location in the tethered acceptor. This systematic aromatic-core engineering results in a star-shaped C3h-positioned molecular geometry. The supramolecular interactions of SMA units in the trimer contribute to enhancements in Tg value, crystallinity, and a red-shifted absorption compared to dimers. These characteristics result in a noteworthy increase in PCE to 18.24 %, coupled with a remarkable short-circuit current density of 27.06 mA cm-2. More significantly, the trimer-based devices delivered an excellent thermal stability with over 95 % of their initial efficiency after 1200 h thermal degradation. Our findings underscore the promise and feasibility of tethered trimeric structures in achieving highly ordered aggregation behavior and increased Tg value in PSCs, simultaneously improving in device efficiency and thermal stability.

Dimeric Giant Molecule Acceptors Featuring N-type Linker: Enhancing Intramolecular Coupling for High-Performance Polymer Solar Cells.

Giant molecular acceptors (GMAs) are typically designed through the conjugated linking of individual small molecule acceptors (SMAs). This design imparts an extended molecular size, elevating the glass transition temperature (Tg) relative to their SMA counterparts. Consequently, it effectively suppresses the thermodynamic relaxation of the acceptor component when blended with polymer donors to construct stable polymer solar cells (PSCs). Despite their merits, the optimization of their chemical structure for further enhancing of device performance remains challenge. Different from previous reports utilizing p-type linkers, here, we explore an n-type linker, specifically the benzothiadiazole unit, to dimerize the SMA units via a click-like Knoevenagel condensation, affording BT-DL. In comparison with B-DL with a benzene linkage, BT-DL exhibits significantly stronger intramolecular super-exchange coupling, a desirable property for the acceptor component. Furthermore, BT-DL demonstrates a higher film absorption coefficient, redshifted absorption, larger crystalline coherence, and higher electron mobility. These inherent advantages of BT-DL translate into a higher power conversion efficiency of 18.49 % in PSCs, a substantial improvement over the 9.17 % efficiency observed in corresponding devices with B-DL as the acceptor. Notably, the BT-DL based device exhibits exceptional stability, retaining over 90 % of its initial efficiency even after enduring 1000 hours of thermal stress at 90 °C. This work provides a cost-effective approach to the synthesis of n-type linker-dimerized GMAs, and highlight their potential advantage in enhancing intramolecular coupling for more efficient and durable photovoltaic technologies.

Modular-Approach Synthesis of Giant Molecule Acceptors via Lewis-Acid-Catalyzed Knoevenagel Condensation for Stable Polymer Solar Cells.

The operational stability of polymer solar cells is a critical concern with respect to the thermodynamic relaxation of acceptor-donor-acceptor (A-D-A) or A-DA'D-A structured small-molecule acceptors (SMAs) within their blends with polymer donors. Giant molecule acceptors (GMAs) bearing SMAs as subunits offer a solution to this issue, while their classical synthesis via the Stille coupling suffers from low reaction efficiency and difficulty in obtaining mono-brominated SMA, rendering the approach impractical for their large-scale and low-cost preparation. In this study, we present a simple and cost-effective solution to this challenge through Lewis acid-catalyzed Knoevenagel condensation with boron trifluoride etherate (BF3 ⋅ OEt2 ) as catalyst. We demonstrated that the coupling of the monoaldehyde-terminated A-D-CHO unit and the methylene-based A-link-A (or its silyl enol ether counterpart) substrates can be quantitatively achieved within 30 minutes in the presence of acetic anhydride, affording a variety of GMAs connected via the flexible and conjugated linkers. The photophysical properties was fully studied, yielding a high device efficiency of over 18 %. Our findings offer a promising alternative for the modular synthesis of GMAs with high yields, easier work up, and the widespread application of such methodology will undoubtedly accelerate the progress of stable polymer solar cells.

Geometry design of tethered small-molecule acceptor enables highly stable and efficient polymer solar cells.

With the power conversion efficiency of binary polymer solar cells dramatically improved, the thermal stability of the small-molecule acceptors raised the main concerns on the device operating stability. Here, to address this issue, thiophene-dicarboxylate spacer tethered small-molecule acceptors are designed, and their molecular geometries are further regulated via the thiophene-core isomerism engineering, affording dimeric TDY-α with a 2, 5-substitution and TDY-ß with 3, 4-substitution on the core. It shows that TDY-α processes a higher glass transition temperature, better crystallinity relative to its individual small-molecule acceptor segment and isomeric counterpart of TDY-ß, and a more stable morphology with the polymer donor. As a result, the TDY-α based device delivers a higher device efficiency of 18.1%, and most important, achieves an extrapolated lifetime of about 35000 hours that retaining 80% of their initial efficiency. Our result suggests that with proper geometry design, the tethered small-molecule acceptors can achieve both high device efficiency and operating stability.

Tethered Small-Molecule Acceptors Simultaneously Enhance the Efficiency and Stability of Polymer Solar Cells.

For polymer solar cells (PSCs), the mixture of polymer donors and small-molecule acceptors (SMAs) is fine-tuned to realize a favorable kinetically trapped morphology and thus a commercially viable device efficiency. However, the thermodynamic relaxation of the mixed domains within the blend raises concerns related to the long-term operational stability of the devices, especially in the record-holding Y-series SMAs. Here, a new class of dimeric Y6-based SMAs tethered with differential flexible spacers is reported to regulate their aggregation and relaxation behavior. In their polymer blends with PM6, it is found that they favor an improved structural order relative to that of Y6 counterpart. Most importantly, the tethered SMAs show large glass transition temperatures to suppress the thermodynamic relaxation in mixed domains. For the high-performing dimeric blend, an unprecedented open circuit voltage of 0.87 V is realized with a conversion efficiency of 17.85%, while those of regular Y6-base devices only reach 0.84 V and 16.93%, respectively. Most importantly, the dimer-based device possesses substantially reduced burn-in efficiency loss, retaining more than 80% of the initial efficiency after operating at the maximum power point under continuous illumination for 700 h. The tethering approach provides a new direction to develop PSCs with high efficiency and excellent operating stability.

Low-cost synthesis of small molecule acceptors makes polymer solar cells commercially viable.

The acceptor-donor-acceptor (A-D-A) or A-DA'D-A structured small molecule acceptors (SMAs) have triggered substantial progress for polymer solar cells (PSCs). However, the high-cost of the SMAs impedes the commercial viability of such renewable energy, as their synthesis via the classical pyridine-catalyzed Knoevenagel condensation usually suffers from low reaction efficiency and tedious purifying work-up. Herein, we developed a simple and cheap boron trifluoride etherate-catalyzed Knoevenagel condensation for addressing this challenge, and found that the coupling of the aldehyde-terminated D unit and the A-end groups could be quantitatively finished in the presence of acetic anhydride within 15 minutes at room temperature. Compared with the conventional method, the high reaction efficiency of our method is related to the germinal diacetate pathway that is thermodynamically favorable to give the final products. For those high performing SMAs (such as ITIC-4F and Y6), the cost could be reduced by 50% compared with conventional preparation. In addition to the application in PSCs, our synthetic approach provides a facile and low-cost access to a wide range of D-A organic semiconductors for emerging technologies.

Long non-coding RNA X-inactive specific transcript suppresses the progression of hepatocellular carcinoma through microRNA-221-3p-targeted regulation of O6-methylguanine-DNA methyltransferase.

MicroRNA-221-3p (miR-221-3p) is an important regulator involved in the progression and prognosis of various cancers. In this study, we aimed to investigate the diagnostic and prognostic value of miR-221-3p expression along with long non-coding RNA X-inactive specific transcript (XIST), which was identified as its upstream regulator in hepatocellular carcinoma (HCC) by bioinformatics analysis, and further validated by RNA immunoprecipitation (RIP) and dual-luciferase reporter assays. Their expression was measured in tumor tissues and corresponding non-tumor tissues by quantitative real-time PCR (qRT-PCR), which revealed that XIST was weakly expressed in HCC cells and tumors, while miR-221-3p was overexpressed. Complete knockdown of XIST enhanced HCC cell proliferation and migration and inhibited apoptosis, as observed by MTT, transwell, and flow cytometry experiments, respectively. Animal studies validated that XIST knockdown induces tumor growth in vivo. In contrast, upregulation of XIST in HCC cells suppressed their proliferation and migration, stimulated apoptosis, and retarded the growth rate of tumors in vivo. These effects were partially reversed by upregulating miR-221-3p expression. Furthermore, we demonstrated that O6-methylguanine-DNA methyltransferase (MGMT) is a downstream target of miR-221-3p. It was weakly expressed in HCC cells and tumors and showed a negative correlation with miR-221-3p. Forced MGMT expression repressed proliferation and migration and enhanced apoptosis in HCC cells. Nevertheless, these anti-tumor effects induced by MGMT overexpression could be abolished by miR-221-3p upregulation. Collectively, our findings reveal that XIST blocks the development of HCC through miR-221-3p-targeted regulation of MGMT. This reveals a new mechanism involved in the development of HCC.

Relationships Between Diurnal Changes of Tongue Coating Microbiota and Intestinal Microbiota.

The oral cavity and the intestine are the main distribution locations of human digestive bacteria. Exploring the relationships between the tongue coating and gut microbiota, the influence of the diurnal variations of the tongue coating microbiota on the intestinal microbiota can provide a reference for the development of the disease diagnosis and monitoring, as well as the medication time. In this work, a total of 39 healthy college students were recruited. We collected their tongue coating microbiota which was collected before and after sleep and fecal microbiota. The diurnal variations of tongue coating microbiota are mainly manifested on the changes in diversity and relative abundance. There are commensal bacteria in the tongue coating and intestines, especially Prevotella which has the higher proportion in both sites. The relative abundance of Prevotella in the tongue coating before sleep has a positive correlation with intestinal Prevotella; the r is 0.322 (p < 0.05). Bacteroides in the intestine had the most bacteria associated with the tongue coating and had the highest correlation coefficient with Veillonella in the oral cavity, which was 0.468 (p < 0.01). These results suggest that the abundance of the same flora in the two sites may have a common change trend. The SourceTracker results show that the proportion of intestinal bacteria sourced from tongue coating is less than 1%. It indicates that oral flora is difficult to colonize in the intestine in healthy people. This will provide a reference for the study on the oral and intestinal microbiota in diseases.

Correlation Analysis of Data of Tongue and Pulse in Patients With Disease Fatigue and Sub-health Fatigue.

Fatigue is one of the most common subjective symptoms of abnormal health state, there is still no reliable and stable evaluation method to distinguish disease fatigue and non-disease fatigue. Studies have shown that tongue diagnosis and pulse diagnosis are the reflection of overall state of the body. This study aims to explore the distribution rules and correlation of data of tongue and pulse in population with disease fatigue and sub-health fatigue and provide a new method of clinical diagnosis of fatigue from the perspective of tongue diagnosis and pulse diagnosis. In this study, a total of 736 people were selected and divided into healthy controls (n = 250), sub-health fatigue group (n = 242), and disease fatigue group (n = 244). TFDA-1 tongue diagnosis instrument and PDA-1 pulse diagnosis instrument were used to collect tongue image and sphygmogram, simple correlation analysis and canonical correlation analysis were used to analyze the correlation of tongue and pulse data about the two groups of fatigue people. The study had shown that tongue and pulse data could provide a certain reference for the diagnosis of different types of fatigue, tongue and pulse data in disease fatigue and sub-health fatigue population had different distribution rules, and there was a simple correlation and canonical correlation in the disease fatigue population, the coefficient of canonical correlation was .649 (P <.05).

Peritumoral Tertiary Lymphoid Structures Correlate With Protective Immunity and Improved Prognosis in Patients With Hepatocellular Carcinoma.

The existence of intratumoral tertiary lymphoid structure (iTLS) has been reported to correlative with favorable clinical outcomes for patients with hepatocellular carcinoma (HCC). However, little is known about the role of peritumoral TLS (pTLS). This study aimed to investigate the prognostic role of pTLS either alone or jointly with iTLS and the potential association with local immune response in HCC. The formation and cellular composition of TLS was evaluated by hematoxylin & eosin and immunohistochemistry. Evaluation of tumor-infiltrating immune cells and formation of germinal center (GC) inside TLS was performed by immunohistochemistry. The gene expression profiles were analyzed by real-time PCR. In a total of 360 patients from two independent cohorts, the pTLS was identified in most, whereas iTLS could be observed in only approximately 30% of HCC specimens. Patients with high pTLS densities were associated with improved outcomes, those present with characteristic morphology of GC, particularly, showing an even better prognosis. The combination of pTLS and iTLS allowed the identification of patients with best prognosis. Tumors with high pTLS density showed significantly increased expression of Th1-, Th17- and immune suppression-related genes, as well as significantly higher infiltration of CD3+, CD8+ and CD20+ cells and lower infiltration of FOXP3+, CD68+ and PD1+ cells. Conclusively, we provide evidence that pTLS is associated with intratumoral immune infiltration, highlighting the dynamic interplay between pTLS and immune cells recruitment. High pTLS density links to a tumor microenvironment with an active immune reaction and improved patient survival and represents a promising prognostic biomarker for HCC.

Hydrophobic Polymeric Additives toward a Long-Term Robust Carbonaceous Mudstone Slope.

Slopes with carbonaceous mudstone (CM) are widely distributed in the southwest of China and have experienced numerous geological disasters in special climate, especially in rainfall conditions. Therefore, novel materials to stabilize CM slopes have attracted increasing interests. However, developing ultra-stable and cost-effective additives for CM slopes is still a great challenge. Herein, a hydrophobic polymeric material (polyvinylidene fluoride, PVDF) is investigated as an additive to enhance the mechanical strength and long-time stability of CM slopes. The PVDF is uniformly dispersed in CM matrix via interfacial interaction. The contact angle of the PVDF-modified carbonaceous mudstone (PVDF-MCM) can reach as high as 103.95°, indicating an excellent hydrophobicity. The unconfined compressive strength (UCS) and tensile strength (TS) of PVDF-MCM have been intensively enhanced to 4.07 MPa and 1.96 MPa, respectively, compared with ~0 MPa of pristine CM. Moreover, the UCS and TS of PVDF-MCM remain at 3.24 MPa and 1.03 MPa even after curing for 28 days in high humidity conditions. Our findings show that the PVDF can improve the hydrophobicity of CM significantly, which leads to super mechanical stability of PVDF-MCM. The excellent performance makes PVDF a promising additive for the development of ultra-stable, long-lifetime and cost-effective carbonaceous mudstone slopes.

A tongue features fusion approach to predicting prediabetes and diabetes with machine learning.

BACKGROUND: Diabetics has become a serious public health burden in China. Multiple complications appear with the progression of diabetics pose a serious threat to the quality of human life and health. We can prevent the progression of prediabetics to diabetics and delay the progression to diabetics by early identification of diabetics and prediabetics and timely intervention, which have positive significance for improving public health. OBJECTIVE: Using machine learning techniques, we establish the noninvasive diabetics risk prediction model based on tongue features fusion and predict the risk of prediabetics and diabetics. METHODS: Applying the type TFDA-1 Tongue Diagnosis Instrument, we collect tongue images, extract tongue features including color and texture features using TDAS, and extract the advanced tongue features with ResNet-50, achieve the fusion of the two features with GA_XGBT, finally establish the noninvasive diabetics risk prediction model and evaluate the performance of testing effectiveness. RESULTS: Cross-validation suggests the best performance of GA_XGBT model with fusion features, whose average CA is 0.821, the average AUROC is 0.924, the average AUPRC is 0.856, the average Precision is 0.834, the average Recall is 0.822, the average F1-score is 0.813. Test set suggests the best testing performance of GA_XGBT model, whose average CA is 0.81, the average AUROC is 0.918, the average AUPRC is 0.839, the average Precision is 0.821, the average Recall is 0.81, the average F1-score is 0.796. When we test prediabetics with GA_XGBT model, we find that the AUROC is 0.914, the Precision is 0.69, the Recall is 0.952, the F1-score is 0.8. When we test diabetics with GA_XGBT model, we find that the AUROC is 0.984, the Precision is 0.929, the Recall is 0.951, the F1-score is 0.94. CONCLUSIONS: Based on tongue features, the study uses classical machine learning algorithm and deep learning algorithm to maximum the respective advantages. We combine the prior knowledge and potential features together, establish the noninvasive diabetics risk prediction model with features fusion algorithm, and detect prediabetics and diabetics noninvasively. Our study presents a feasible method for establishing the association between diabetics and the tongue image information and prove that tongue image information is a potential marker which facilitates effective early diagnosis of prediabetics and diabetics.

Clinical data mining on network of symptom and index and correlation of tongue-pulse data in fatigue population.

BACKGROUND: Fatigue is a kind of non-specific symptom, which occurs widely in sub-health and various diseases. It is closely related to people's physical and mental health. Due to the lack of objective diagnostic criteria, it is often neglected in clinical diagnosis, especially in the early stage of disease. Many clinical practices and researches have shown that tongue and pulse conditions reflect the body's overall state. Establishing an objective evaluation method for diagnosing disease fatigue and non-disease fatigue by combining clinical symptom, index, and tongue and pulse data is of great significance for clinical treatment timely and effectively. METHODS: In this study, 2632 physical examination population were divided into healthy controls, sub-health fatigue group, and disease fatigue group. Complex network technology was used to screen out core symptoms and Western medicine indexes of sub-health fatigue and disease fatigue population. Pajek software was used to construct core symptom/index network and core symptom-index combined network. Simultaneously, canonical correlation analysis was used to analyze the objective tongue and pulse data between the two groups of fatigue population and analyze the distribution of tongue and pulse data. RESULTS: Some similarities were found in the core symptoms of sub-health fatigue and disease fatigue population, but with different node importance. The node-importance difference indicated that the diagnostic contribution rate of the same symptom to the two groups was different. The canonical correlation coefficient of tongue and pulse data in the disease fatigue group was 0.42 (P < 0.05), on the contrast, correlation analysis of tongue and pulse in the sub-health fatigue group showed no statistical significance. CONCLUSIONS: The complex network technology was suitable for correlation analysis of symptoms and indexes in fatigue population, and tongue and pulse data had a certain diagnostic contribution to the classification of fatigue population.

Association of miR-4293 rs12220909 polymorphism with cancer risk: A meta-analysis of 8394 subjects.

BACKGROUND: Several studies have investigated miR-4293 rs12220909 polymorphisms and cancer susceptibility and yielded different results. Because of this controversy, we designed a meta-analysis to assess comprehensively the association of the rs12220909 polymorphism with cancer risk. METHODS: Relevant articles were collected by searching the databases of PubMed, Embase, Web of Science, China National Knowledge Infrastructure (CNKI), and WanFang. Data on rs12220909 in cancer patients and controls were extracted. Sensitivity analyses and publication bias assessments were performed. RESULTS: Five studies with 3820 cases and 4574 controls were included in our meta-analysis. Pooled analyses showed that the rs12220909 polymorphism was not associated with cancer risk in any genetic model. (C vs G: odds ratio [OR] = 0.89, 95% confidence interval [CI] = 0.74-1.07; GC vs GG: OR = 0.83, 95% CI = 0.67-1.03; CC vs GG: OR = 1.06, 95% CI = 0.82-1.36; CC+GC vs GG: OR = 0.84, 95% CI = 0.69-1.03; CC vs GC+GG: OR = 1.10, 95% CI = 0.85-1.40). CONCLUSIONS: Our results indicate that rs12220909 is not associated with cancer risk. Larger, well-designed multicenter studies are needed to further explore the association of miR-4293 rs12220909 polymorphism with cancer risk.

The Role of Nanotechnology in Subgrade and Pavement Engineering: A Review.

Nanotechnology is an extension of sciences and technologies that deal with particles less than 100 nm. This paper reviews previous studies on how nanomaterials work and what their advantages are in subgrade and pavement engineering. In subgrade engineering, the nanomaterials particles can not only improve the physicochemical and mechanical properties of subgrade soils by filling the voids between soil particles but also promote hydration reaction between cement and ion exchange between soil particles. In pavement engineering, the water stability, rutting resistance, fatigue resistance and optical properties of flexible pavements are enhanced by adding nanomaterials into the asphalt mixture. Nanosilica enhances the interface between cement pastes and aggregates and promotes the pozzolanic reaction of concrete, thus, mechanical properties of concrete pavements are improved. Compared with traditional materials, nanomaterials play a promising role in subgrade and pavement engineering, benefitting from their environmental friendliness, lower environmental disturbance, better price/performance ratio and higher durability.

Study of the Strength of Disintegrated Carbonaceous Mudstone Modified with Nano-Al2O3 and Cement.

Embankments filled with disintegrated carbonaceous mudstone (DCM) are prone to uneven settlements because of water-softening property and secondary disintegration of carbonaceous mudstone. To address this problem, nano-Al²O³ and cement were proposed in this study to improve the strength of DCM. Many nano-Al²O³- and cement-modified DCM (NACDCM) specimens with various nano-Al²O³ contents were prepared. Unconfined compression tests and triaxial compression tests were performed to examine the strengths of NACDCM under different conditions. Moreover, X-ray diffraction (XRD) analyses and scanning electron microscopy (SEM) observations were performed to reveal the microscopic mechanism for modification of the NACDCM. Macroscopic results showed that the unconfined compressive strength of NACDCM reached maximum when the nano-Al²O³ content was 0.2%. The cohesion showed positive correlation with nano-Al²O³ content while the angle of internal friction presented negative correlation with nano-Al²O³ content. Moreover, microscopic results indicated that nano-Al²O³ and cement improved the strength of NACDCM, mainly through cement hydration reaction, pozzolanic reaction, ion exchange, gel effect and filling effect.

Effect of Nanotalc on the Shear Strength of Disintegrated Carbonaceous Mudstone.

This work was aimed to improve the shear strength of disintegrated carbonaceous mudstone (DCM) with nanotalc (NT). A series of direct shear tests were carried out on the NT-modified DCM specimens to determine their shear strengths at various NT concentrations. Subsequently, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were performed to reveal the underlying mechanism which the results showed that shear strength was first increased and then decreased with increasing certain NT concentration. Moreover, the increase in NT concentration also resulted in rise in cohesion and reduction in angle of internal friction. The optimum NT concentration for shear strength improvement of DCM is 4%. This improvement of shear strength is achieved because NT can fill the pores in DCM and its products can bind with particles. This results in formation of large aggregates owing to the small size, strong adsorption capacity and cation-exchange capacity.

Tongue color clustering and visual application based on 2D information.

PURPOSE: Studies have shown the association between tongue color and diseases. To help clinicians make more objective and accurate decisions quickly, we take unsupervised learning to deal with the basic clustering of tongue color in a 2D way. METHODS: A total of 595 typical tongue images were analyzed. The 3D information extracted from the image was transformed into 2D information by principal component analysis (PCA). K-Means was applied for clustering into four diagnostic groups. The results were evaluated by clustering accuracy (CA), Jaccard similarity coefficient (JSC), and adjusted rand index (ARI). RESULTS: The new 2D information totally retained 89.63% original information in the L*a*b* color space. And our methods successfully classified tongue images into four clusters and the CA, ARI, and JSC were 89.04%, 0.721, and 0.890, respectively. CONCLUSIONS: The 2D information of tongue color can be used for clustering and to improve the visualization. K-Means combined with PCA could be used for tongue color classification and diagnosis. Methods in the paper might provide reference for the other research based on image diagnosis technology.