Impact of Freeze-Thaw Cycles on the Long-Term Performance of Concrete Pavement and Related Improvement Measures: A Review.

Freeze-thaw damage is one of the most severe threats to the long-term performance of concrete pavement in cold regions. Currently, the freeze-thaw deterioration mechanism of concrete pavement has not been fully understood. This study summarizes the significant findings of concrete pavement freeze-thaw durability performance, identifies existing knowledge gaps, and proposes future research needs. The concrete material deterioration mechanism under freeze-thaw cycles is first critically reviewed. Current deterioration theories mainly include the hydrostatic pressure hypothesis, osmolarity, and salt crystallization pressure hypothesis. The critical saturation degree has been proposed to depict the influence of internal saturation on freeze-thaw damage development. Meanwhile, the influence of pore solution salinity on freeze-thaw damage level has not been widely investigated. Additionally, the deterioration mechanism of the typical D-cracking that occurs in concrete pavement has not been fully understood. Following this, we investigate the coupling effect between freeze-thaw and other loading or environmental factors. It is found that external loading can accelerate the development of freeze-thaw damage, and the acceleration becomes more evident under higher stress levels. Further, deicing salts can interact with concrete during freeze-thaw cycles, generating internal pores or leading to crystalline expansion pressure. Specifically, freeze-thaw development can be mitigated under relatively low ion concentration due to increased frozen points. The interactive mechanism between external loading, environmental ions, and freeze-thaw cycles has not been fully understood. Finally, the mitigation protocols to enhance frost resistance of concrete pavement are reviewed. Besides the widely used air-entraining process, the freeze-thaw durability of concrete can also be enhanced by using fiber reinforcement, pozzolanic materials, surface strengthening, Super Absorbent Polymers (SAPs), and Phase Change Materials. This study serves as a solid base of information to understand how to enhance the freeze-thaw durability of concrete pavement.

[A retrospective study on incisor root resorption in patients treated with bracketless invisible appliance and straight wire appliance].

PURPOSE: To assess root resorptions in patients treated with bracketless invisible appliance and straight wire appliance using cone-beam CT (CBCT). METHODS: Twenty-eight patients treated with bracketless invisible appliance (as experimental group) or straight wire appliance (as control group) were randomly selected. CBCT images were analyzed at 3 time points (pre-operation, 6 month after operation, post-operation). Root resorption was calculated using root length at 3 time points. The difference between the 2 groups was analyzed with SPSS16.0 software package. To those teeth with no root length reduction, the bone defect was evaluated using CBCT. RESULTS: After 6-month of treatment, 47.3% teeth from the experimental group had root resorption, while 68.3% in the control group. There was significant difference between the 2 groups (P<0.05). Root absorption of maxillary central incisors from the 2 groups was more severe than other teeth (55% in the experimental group, and 75% in the control group). After orthodontic treatment, the incidence of root resorption in the control groups increased to be 85.3% and 68.3% in the experimental group (P<0.05). To those teeth with no root resorption, bone defect was more common in the palatal side (18% in the experimental group, 14% in the control group). CONCLUSIONS: Compared with straight wire appliance, patients using bracketless invisible appliance suffer from less root resorption.

Semi-automatic segmentation of femur based on harmonic barrier.

BACKGROUND AND OBJECTIVE: Segmentation of the femur from the hip joint in computed tomography (CT) is an important preliminary step in hip surgery planning and simulation. However, this is a time-consuming and challenging task due to the weak boundary, the varying topology of the hip joint, and the extremely narrow or blurred space between the femoral head and the acetabulum. To address these problems, this study proposed a semi-automatic segmentation framework based on harmonic fields for accurate segmentation. METHODS: The proposed method comprises three steps. First, with high-level information provided by the user, shape information provided by neighboring slices as well as the statistical information in the mask, a region selection method is proposed to effectively locate joint space for the harmonic field. Second, incorporated with an improved gradient, the harmonic field is used to adaptively extract a curve as the barrier that separates the femoral head from the acetabulum accurately. Third, a divide and conquer segmentation strategy based on the harmonic barrier is used to combine the femoral head part and body part as the final segmentation result. RESULTS: We have tested 40 hips with considerately narrow or disappeared joint spaces. The experimental results are evaluated based on Jaccard, Dice, directional cut discrepancy (DCD) and receiver operating characteristic (ROC), and we achieve the higher Jaccard of 84.02%, Dice of 85.96%, area under curve (AUC) of 89.3%, and the lower error with DCD of 0.52mm. The effective ratio of our method is 79.1% even for cases with severe malformation. The results show that our method performs best in terms of effectiveness and accuracy on the whole data set. CONCLUSIONS: The proposed method is efficient to segment femurs with narrow joint space. The accurate segmentation results can assist the physicians for osteoarthritis diagnosis in future.

[Coculture of stem cells from the apical papilla and human umbilical vein endothelial cells enhances the angiogenic potential of dental pulp tissues].

PURPOSE: To observe the effect of coculture of stem cells from the apical papilla (SCAPs) and human umbilical vein endothelial cells (HUVECs) on the angiogenic potential of dental pulp tissues. METHODS: SCAPs were incubated in osteo/odontogenic, adipogenic, neurogenic induction medium and α-MEM medium, whose multilineage differentiation capacities were confirmed using alizarin red staining, oil red O staining and ßIII-tubulin immunofluorescent staining. The tubular length, branching points number and junctional areas were detected after 3, 6, 9 h since cells were seeded onto matrigel, and the data was analyzed using SPSS 16.0 software package. RESULTS: SCAPs in the experimental groups were detected having more lipid droplets, mineralization nodules and neuron-like cells. Coculture of SCAPs and HUVECs formed more vessel-like structures in tubular formation assay. CONCLUSIONS: SCAPs are capable of differentiating into fat, bone, and nerve-like cells in vitro. Coculture of SCAPs and HUVECs can enhance the angiogenic potential of dental pulp tissues.

Lactobacillus acidophilus ATCC 4356 attenuates the atherosclerotic progression through modulation of oxidative stress and inflammatory process.

The aim of this study was to investigate the effect of Lactobacillus (L.) acidophilus ATCC 4356 on the progression of atherosclerosis in Apoliprotein-E knockout (ApoE(-/-)) mice and the underlying mechanisms. Eight week-old ApoE(-/-) mice were treated with L. acidophilus ATCC 4356 daily for 12 weeks. The wild type (WT) mice or ApoE(-/-) mice in the vehicle group were treated with saline only. Body weights, serum lipid levels, aortic atherosclerotic lesions, and tissue oxidative and inflammatory statuses were examined among the groups. As compared to ApoE(-/-) mice in the vehicle group, ApoE(-/-) mice treated with L. acidophilus ATCC 4356 had no changes in body weights and serum lipid profiles, but showed decreased atherosclerotic lesion size in en face aorta. In comparison with WT mice, ApoE(-/-) mice in the vehicle group showed higher levels of serum malondialdehyde (MDA), oxidized low density lipoprotein (oxLDL) and tumor necrosis factor-alpha (TNF-α), but lower levels of interleukin-10 (IL-10) and superoxide dismutase (SOD) activities in serum. Administration of L. acidophilus ATCC 4356 could reverse these trends in a dose-dependent manner in ApoE(-/-) mice. Furthermore, ApoE(-/-) mice treated with L. acidophilus ATCC 4356 showed an inhibition of translocation of NF-κB p65 from cytoplasm to nucleus, suppression of degradation of aortic IκB-α, and improvements of gut microbiota distribution, as compared to ApoE(-/-) mice in the vehicle group. Our findings suggest that administration of L. acidophilus ATCC 4356 can attenuate the development of atherosclerotic lesions in ApoE(-/-) mice through reducing oxidative stress and inflammatory response.

FOXO1 expression and regulation in endometrial tissue during the menstrual cycle and in early pregnancy decidua.

AIMS: To determine FOXO1 (forkhead box O1) expression in the human endometrium during the menstrual cycle and decidua of early pregnancy, as well as FOXO1 regulation in endometrial stromal cells (ESC). METHODS: Immunohistochemistry, RT-qPCR, and Western blot analyses evaluated cellular localization and altered FOXO1 expression in the endometrium during the menstrual cycle and decidua of early pregnancy (proliferative phase, n = 12; early-secretory phase, n = 7; mid-secretory phase, n = 10; late-secretory phase, n = 10; early pregnancy, n = 12). Using RT-qPCR and Western blot, we studied the regulation of FOXO1 by 8-bromo-cAMP, 4-pregnene-3,20-dione, 17ß-estradiol, and human chorionic gonadotrophin in ESC (n = 5). RESULTS: The expression level of FOXO1 in human endometrial tissue fluctuated with the menstrual cycle. If pregnancy occurred, the expression of FOXO1 was further increased (p < 0.05) and cAMP regulated FOXO1 expression in ESC. In addition, 4-pregnene-3,20-dione cooperatively stimulated FOXO1 expression with cAMP. We also observed FOXO1 expression during in vitro cAMP-induced decidualization. CONCLUSIONS: The pattern of FOXO1 expression suggests a potential role for FOXO1 in implantation and decidualization.

Room temperature aldol reactions using magnetic Fe3O4@Fe(OH)3 composite microspheres in hydrogen bond catalysis.

Fe(3)O(4)@Fe(OH)(3) composite microspheres are highly active, environmentally friendly and easy to recycle catalysts for aldol reactions, which are catalyzed by a solid-liquid interfacial hydrogen bond catalyst at room temperature.

Predicting subcellular location of apoptosis proteins based on wavelet transform and support vector machine.

Apoptosis proteins have a central role in the development and homeostasis of an organism. These proteins are very important for understanding the mechanism of programmed cell death. As a result of genome and other sequencing projects, the gap between the number of known apoptosis protein sequences and the number of known apoptosis protein structures is widening rapidly. Because of this extremely unbalanced state, it would be worthwhile to develop a fast and reliable method to identify their subcellular locations so as to gain better insight into their biological functions. In view of this, a new method, in which the support vector machine combines with discrete wavelet transform, has been developed to predict the subcellular location of apoptosis proteins. The results obtained by the jackknife test were quite promising, and indicated that the proposed method can remarkably improve the prediction accuracy of subcellular locations, and might also become a useful high-throughput tool in characterizing other attributes of proteins, such as enzyme class, membrane protein type, and nuclear receptor subfamily according to their sequences.

Using support vector machines to distinguish enzymes: approached by incorporating wavelet transform.

The enzymatic attributes of newly found protein sequences are usually determined either by biochemical analysis of eukaryotic and prokaryotic genomes or by microarray chips. These experimental methods are both time-consuming and costly. With the explosion of protein sequences registered in the databanks, it is highly desirable to develop an automated method to identify whether a given new sequence belongs to enzyme or non-enzyme. The discrete wavelet transform (DWT) and support vector machine (SVM) have been used in this study for distinguishing enzyme structures from non-enzymes. The networks have been trained and tested on two datasets of proteins with different wavelet basis functions, decomposition scales and hydrophobicity data types. Maximum accuracy has been obtained using SVM with a wavelet function of Bior2.4, a decomposition scale j=5, and Kyte-Doolittle hydrophobicity scales. The results obtained by the self-consistency test, jackknife test and independent dataset test are encouraging, which indicates that the proposed method can be employed as a useful assistant technique for distinguishing enzymes from non-enzymes.

Using support vector machines for prediction of protein structural classes based on discrete wavelet transform.

The prediction of secondary structure is a fundamental and important component in the analytical study of protein structure and functions. How to improve the predictive accuracy of protein structural classification by effectively incorporating the sequence-order effects is an important and challenging problem. In this study, a new method, in which the support vector machine combines with discrete wavelet transform, is developed to predict the protein structural classes. Its performance is assessed by cross-validation tests. The predicted results show that the proposed approach can remarkably improve the success rates, and might become a useful tool for predicting the other attributes of proteins as well.

[Molecular authentication of Dendrobium chrysanthum from its allied species of Dendrobium].

OBJECTIVE: To define molecular characters to distinguish D. chrysanthum from its allied species D. primulinum, D. lituiflorum, D. aphyllum, D. crepidatum. METHOD: The molecular characteristics of D. chrysanthum and its allied species were compared. The sequences of rDNA ITS regions were exploited to explore the evidence for authentication D. chrysanthum and its allied species. RESULT: Although the morphological difference was slight, the sequence difference of ITS regions among five rDNAs was obvious and stable. Fifteen sites of ITS region were defined as DNA character to identify D. chrysanthum from the other four allied species. CONCLUSION: The difference of rDNA ITS sequences can be used to authenticate accurately D. chrysanthum from three allied species of Dendrobium.

[Database establishment of the whole rDNA ITS region of Dendrobium species of "fengdou" and authentication by analysis of their sequences].

AIM: To establish the whole rDNA ITS region sequence database of various Dendrobium species of "Fengdou" and to authenticate exactly the inspected species of "Fengdou". METHODS: The rDNA ITS regions of various Dendrobium species of "Fengdou" were amplified and sequenced. The database of their rDNA ITS regions was established in order to authenticate the inspected species by means of the softwares of CLUSTRAL and MEGA which were used to analyze the rDNA ITS region. RESULTS: A database of the rDNA ITS sequences of 21 species of Dendrobium has been established. The notable and stable differences of the interspecies of the rDNA ITS regions have been demonstrated. The numbers of transitions and transversions among 21 species are 11-122. The variable sites are 341 while the informative sites are 195. The ITS sequence differences between the outgroup species (Pholidota yunnanensis) and species of "Fengdou" are obvious. The numbers of transitions and transversions are 131-161. The population differences of the rDNA ITS region of various species of "Fengdou" are very small (0-6). CONCLUSION: On the basis of the database of various Dendrobium species of "Fengdou" and two genetics software, the botanical origin of the inspected species of "Fengdou" has been authenticated successfully by sequencing the rDNA ITS regions.

Database establishment of the whole rDNA ITS region of Dendrobium species of "fengdou" and authentication by analysis of their sequences / 药学学报

<p><b>AIM</b>To establish the whole rDNA ITS region sequence database of various Dendrobium species of "Fengdou" and to authenticate exactly the inspected species of "Fengdou".</p><p><b>METHODS</b>The rDNA ITS regions of various Dendrobium species of "Fengdou" were amplified and sequenced. The database of their rDNA ITS regions was established in order to authenticate the inspected species by means of the softwares of CLUSTRAL and MEGA which were used to analyze the rDNA ITS region.</p><p><b>RESULTS</b>A database of the rDNA ITS sequences of 21 species of Dendrobium has been established. The notable and stable differences of the interspecies of the rDNA ITS regions have been demonstrated. The numbers of transitions and transversions among 21 species are 11-122. The variable sites are 341 while the informative sites are 195. The ITS sequence differences between the outgroup species (Pholidota yunnanensis) and species of "Fengdou" are obvious. The numbers of transitions and transversions are 131-161. The population differences of the rDNA ITS region of various species of "Fengdou" are very small (0-6).</p><p><b>CONCLUSION</b>On the basis of the database of various Dendrobium species of "Fengdou" and two genetics software, the botanical origin of the inspected species of "Fengdou" has been authenticated successfully by sequencing the rDNA ITS regions.</p>

Molecular authentication of Dendrobium chrysanthum from its allied species of Dendrobium / 中国中药杂志

<p><b>OBJECTIVE</b>To define molecular characters to distinguish D. chrysanthum from its allied species D. primulinum, D. lituiflorum, D. aphyllum, D. crepidatum.</p><p><b>METHOD</b>The molecular characteristics of D. chrysanthum and its allied species were compared. The sequences of rDNA ITS regions were exploited to explore the evidence for authentication D. chrysanthum and its allied species.</p><p><b>RESULT</b>Although the morphological difference was slight, the sequence difference of ITS regions among five rDNAs was obvious and stable. Fifteen sites of ITS region were defined as DNA character to identify D. chrysanthum from the other four allied species.</p><p><b>CONCLUSION</b>The difference of rDNA ITS sequences can be used to authenticate accurately D. chrysanthum from three allied species of Dendrobium.</p>