The epoxy nanocomposites with Fe3O4 modified graphene oxide (Fe3O4/GO) were used to influence the micro-cracks resistance of carbon fiber reinforced epoxy (CF/EP) laminate at 77 K. Fe3O4/GO with good ...paramagnetic properties were prepared by co-precipitation method and used to modify epoxy for cryogenic applications. Fe3O4/GO modified CF/EP laminates were also prepared through vacuum-assisted resin transfer molding (VARTM). The results show that the Fe3O4/GO can effectively improve the mechanical properties of epoxy (EP) matrix at 77 K and reduce the coefficient of thermal expansion (CTE) of EP matrix. It also can obviously improve the micro-cracks resistance of CF/EP composites at 77 K. Compared to neat EP, the CTE of Fe3O4/GO modified EP composite is decreased 51.6%. Compared to CF/EP composite, the micro-cracks density of Fe3O4/GO modified CF/EP composite at 77 K is decreased 60.0%.
Short text is an important form of information dissemination and opinion expression in various social media platforms. Sentiment analysis of short texts is beneficial for the understanding of ...customers' emotional state, obtaining customers' opinions and attitudes toward events, information and products, however, is difficult because the sparsity of the short-text data. Unlike the traditional methods using the external knowledge, this paper proposes a bi-level attention model for sentiment analysis of short texts, which does not rely on external knowledge to deal with the data sparsity. Specifically, at word level, our model improves the effect of word representation by introducing latent topic information into word-level semantic representation. Neural topic model is used to discover the latent topic of the text. A new topic-word attention mechanism is presented to explore the semantics of words from the perspective of topic-word association; At the sequence level, a secondary attention mechanism is used to capture the relationship between local and global sentiment expression. Experiments on the ChnSentiCorp-Htl-ba-10000 and NLPCC-ECGC datasets validate the effectiveness of the BAM model.
Nitrogen-doped TiO
2 nanotubes were synthesized by annealing of the anodized titania nanotubes with ammonia at the temperature of 500 °C. The ordered structure of titania nanotubes maintained after ...the nitrogen doping process, as is evidenced by SEM observations. Detailed structural analysis revealed that the phase transformation temperature of titania nanotube from anatase to rutile is decreased after nitrogen doping. The XRD patterns of nitrogen-doped titania exhibit an increased peak intensity and a decreased FWHM in the (110) peak of rutile in comparison with those of undoped titania under the same annealing conditions, indicating that nitrogen doping may have facilitated the phase transition at the annealing temperature of 500 °C, which is in consistence with the analysis of Raman spectra as the comparison of A
1g and
E
g Raman peaks of rutile in the nitrogen-doped and undoped titania.
A new fluorogermanate glass Cao, Guoxi; Lin, Fengying; Hu, Hefang ...
Journal of non-crystalline solids,
10/2003, Letnik:
326-327
Journal Article
Recenzirano
The effect of substitutions of BaF2 for BaO on the properties of BaO-Ga2O3-GeO2 glasses was investigated. The Tg, Tx, refractive index and IR transmitting spectra were determined. The replacement of ...O by F decreases the refractive index, the Tg and the Tx while increases the DT. The concentration of hydroxyl decreases as fluoride is introduced. The glass-forming regions in the ternary systems BaF2-MF3-GeO2 (M=Al, Ga, In) were determined. A wide glass-forming region was found in the BaF2-GaF3-GeO2 system, while the glass-forming region in the other two systems is narrower. The characteristic temperatures and the transmitting spectrum of some typical glasses were also measured. 9 refs.
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•An electrochemiluminescent biosensor based on Au@CDs for detection of CTCs is described.•The prepared Au@CDs possess significant enhanced electrochemiluminescence emission.•The ...proposed method was sensitive, separation-free and label-free strategy.
In this work, new gold@carbon dots nanoalloys (Au@CDs) were synthesized by directly heating carbon dots (CDs) and HAuCl4 aqueous solution to boiling. The as-synthesized Au@CDs exhibited 12-fold enhancement in the ECL emission compared to the single CDs. The high luminous efficiency Au@CDs was further used to fabricate an ECL cytosensor for the direct detection of circulating tumor cells (CTCs) in serum by ligation of a cell-specific aptamer. Briefly, human mucin1 protein (MUC1) aptamer was immobilized onto the surface of Au@CDs on the electrode for capturing MUC1-positive MCF-7 cells (a type of CTCs). On the basis of the increased steric hindrance, the captured MCF-7 cells can be quantitatively detected. Our strategy was free from complicated separation and labeling treatment, and realized the detection of MCF-7 cells (a type of CTCs) from 100 to 10,000 cells/mL with a detection limit of 34 cells/mL, offering promising applications in ultrasensitive routine clinical analysis and point-of-care testing.
To compare small incision lenticule extraction (SMILE) and laser assisted stromal in situ keratomileusis (LASIK) for astigmatism correction.
Systematic review and meta-analysis
We reviewed published ...studies comparing outcomes after LASIK and SMILE for astigmatism correction by querying PubMed, EMBASE, Cochrane, and Web of Science, with a cut-off date of September 3, 2022. We also compared the changes in visual acuity, refraction, and high-order aberrations between the surgeries. Astigmatism correction outcomes in the low-to-moderate group (less than or equal to −2.00 D) and high group (greater than −2.00 D) were evaluated using vector analysis. The Cochrane risk of bias tool in RevMan software was used for randomized studies (RCT), and Risk Of Bias In Nonrandomized Studies − of Interventions (ROBINS-I) was used for the nonrandomized studies (NRSs).
There were 17 studies (5 randomized studies and 12 cohort studies), including 1,985 eyes. A statistically significant difference was found in the correction index (mean difference MD = −0.02, 95% confidence interval CI = −0.04 to −0.01, P =0.01), although there was no significant difference in the index of success (MD = 0.01, 95% CI = −0.03 to 0.05, P =0.51), different vector (MD = 0.07, 95% CI = 0.00 to 0.13, P =0.04), and angle of error (MD = 0.56, 95% CI = −0.34 to 1.45, P =0.22) between SMILE and LASIK. However, for low-to-moderate astigmatism correction, SMILE exhibited a smaller correction index (MD = −0.08, 95% CI= −0.13 to −0.02, P =0.008) and a larger difference vector (MD = 0.18, 95% CI = 0.09 to 0.27, P <0.0001) than LASIK. There was no significant difference between the different procedures in visual acuity and refraction (spherical equivalent: MD = −0.04, 95% CI = −0.08 to 0.01, P =0.15) or high-order aberration (MD = −0.01, 95% CI = −0.07 to 0.04, P =0.67), except spherical aberration (MD = −0.12, 95% CI = −0.23 to −0.01, P =0.04). The risk of bias was moderate in most studies because of poor reporting of several bias domains for RCTs, and because of confounding and selective outcome reporting for NRSs.
When used to treat severe astigmatism, both SMILE and LASIK provide effective and predictable results and generally have equivalent outcomes. However, evidence reveals a tendency toward undercorrection in the SMILE groups for astigmatism correction. In addition, LASIK has a greater probability of causing postoperative spherical aberration.
Domesticated chickens have a wide variety of phenotypes, in contrast with their wild progenitors. Unlike other chicken breeds, Xichuan black-bone chickens have blue-shelled eggs, and black meat, ...beaks, skin, bones, and legs. The breeding history and the economically important traits of this breed have not yet been explored at the genomic level. We therefore used whole genome resequencing to analyze the breeding history of the Xichuan black-bone chickens and to identify genes responsible for its unique phenotype.
Principal component and population structure analysis showed that Xichuan black-bone chicken is in a distinct clade apart from eight other breeds. Linkage disequilibrium analysis showed that the selection intensity of Xichuan black-bone chickens is higher than for other chicken breeds. The estimated time of divergence between the Xichuan black-bone chickens and other breeds is 2.89 ka years ago. Fst analysis identified a selective sweep that contains genes related to melanogenesis. This region is probably associated with the black skin of the Xichuan black-bone chickens and may be the product of long-term artificial selection. A combined analysis of genomic and transcriptomic data suggests that the candidate gene related to the black-bone trait, EDN3, might interact with the upstream ncRNA LOC101747896 to generate black skin color during melanogenesis.
These findings help explain the unique genetic and phenotypic characteristics of Xichuan black-bone chickens, and provide basic research data for studying melanin deposition in animals.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
OBJECTIVETo investigate the clinical effect of platelet-rich fibrin (PRF) combined with guided bone regeneration (GBR) in the reconstruction of peri-implantitis bone defect. METHODSThis prospective ...study included 80 patients with peri-implantitis who underwent implant restoration in the Department of Stomatology in our hospital. The eligible patients were randomly divided into control group and observation group, with 40 cases in each group. Patients in the control group were treated with flap curettage combined with GBR, while those in the observation group received a mixture of PRF and bone powder implanted with GBR and covered with PRF biofilm. The differences of pain 24 hours after surgery, bleeding at 7 days after surgery, and the degree of bone defect between the two groups at 60 days after surgery were compared. At 60 days and 120 days after surgery, separately, the regenerated bone density of patients in the two groups was measured, analyzed and compared. The degree of regenerated bone defect in transverse and longitudinal directions after 60 days was compared between the two reconstruction procedures. RESULTSThe pain at 24 hours after surgery and the bleeding at 7 days after surgery in the observation group were milder than those in the control group (P<0.001). There was significant difference in the degrees of bone defect at 60 days after surgery (P<0.05). Compared with the control group, the regenerated bone density of the observation group was significantly higher both at 60 days and 120 days after surgery (P<0.001). CONCLUSIONThe combination of PRF and GBR technology has an obvious effect in repairing bone defects in patients with peri-implantitis, and can reduce the pain of patients during the repair process.
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A dual-potential ratiometric electrochemiluminescence biosensor based on Au@CDs nanoflowers, Au@luminol nanoparticles and an enzyme-free DNA nanomachine for ultrasensitive p53 DNA ...detection.
•A dual-potential ratiometric ECL biosensor was fabricated based on Au@CDs and Au@luminol.•An enzyme-free DNA walker was employed.•Sensitive and accurate detection of p53 DNA were obtained.
Herein, an amplified electrochemiluminescence (ECL) ratiometric biosensor for p53 DNA sequence assay was described based on gold@carbon dots nanoflowers (Au@CDs), gold@luminol nanoparticles (Au@luminol) as luminophors and an enzyme-free DNA walker for signal amplification. The ratiometric strategy endowed the sensor with a prominent accuracy. Taking advantage of DNA-walker signal amplification feature, a high sensitivity for target detection was achieved. Under the optimal conditions, the designed biosensor exhibited a lower limit of 0.34 fM and wide linear range from 1 fM to 10 pM for p53 DNA sequence detection. In particular, compared with traditional Ru(bpy)33+/Ru(bpy)32+ derivatives and semiconductor nanoparticles, Au@luminol and Au@CDs have the advantages of cost-effective, excellent biocompatibility, and easy labeling, which offered new opportunity for building ratiometric ECL biosensor platform.
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