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Background Hair color retention and rejuvenation have recently emerged as a new research hot spot, with many studies focused on developing treatments to prevent premature greying. Aim This study is aimed to explore the hair-blacking effects and possible mechanisms of Cerasus serrulata flower extracts (CSE) using a C57BL/6 premature greying mouse model. Materials and Methods The variations in hair follicle number, hair follicle depth and cortical thickness were evaluated by hematoxylin and eosin staining. The quantity changes of melanocytes were also evaluated using Masson-Fontana Melanin staining. The relative abundance of vascular endothelial growth factor (VEGF), β-catenin and tyrosinase transcripts following transformed growth were further quantified using RT-qPCR and immunofluorescence. The changes in protein level expression of β-catenin, VEGF and tyrosinase were also evaluated by western blot. Results The β-catenin and VEGF expression were significantly up-regulated in skin tissues treated with C. serrulata extracts, promoting hair growth and blackening. Conclusion CSE can promote the efficient hair-blacking likely via the VEGF pathway, making it a potential therapeutic candidate for treating premature greying.

Autism spectrum disorders (ASD) are characterized by reduced pain empathy-a process that is grounded in first-hand pain perception. Because autistic traits are continuously distributed in the general population, we hypothesized that first-hand pain sensitivity would mediate the link between autistic traits and pain empathy. After controlling for alexithymia, higher autistic traits were associated with lower cognitive and emotional empathy in response to others' pain, as well as lower sensitivity to cold and heat pain (higher cold pain tolerance and lower laser heat pain-intensity ratings). Importantly, pain sensitivity fully mediated the link between autistic traits and pain empathy. These findings highlight the role of atypical first-hand pain sensitivity in the lack of pain empathy observed in people with high autistic traits or ASD.

The influence of the surrounding building topography of the Datong-Xi?an high-speed railway foundation on the wind environment and the thermal comfort is studied, especially the outdoor wind environment and indoor air-flow organization of the surrounding buildings are analyzed numerically, and the building terrain and the indoor temperature and the wind?s speed distribution are systematically evaluated. The results show that the surrounding terrain of the roadbed has a significant effect on the wind environment of the site, affecting the natural ventilation in summer and wind-proof and energy-saving in winter. The terrain surrounding of the building in summer reduces the wind speed by 30.5%, and it increases in winter by 31.6%; the wind speed in the indoor personnel activity area of the building around the roadbed is less than 0.35 m/s, leading to a comfortable body feeling.

Ice thermal storage (ITS) performance for cooling systems is greatly influenced by the poor thermal conductivity of phase change material (PCM). The effect of natural convection on the melting process is significant for heat transfer enhancement. Thus, the melting performance of PCM in a shell-and-tube latent heat storage (STLHS) unit is numerically studied by considering natural convection in terms of various heat source positions and configurations, i.e., central position, eccentric position, and flat-tube type. Temperature distribution, melting time, and the overall heat transfer coefficient during the process are investigated. The results show that the circulation vortex formed by natural convection is a dominant factor that affects melting front evolution and the overall heat transfer coefficient. When input heat flux is relatively weak, PCM below the heat source is liquefied first. In contrast, PCM in the upper part melts earlier when the heat flux is excellent. The overall heat transfer coefficient decreases sharply with the increase in melting time in the early stage. Then, the heat transfer coefficient tends to be constant. PCM in an STLHS unit with a heat source in a lower position and a configuration of vertical flat-tube type has a desirable performance when compared with other cases, which could provide good support for ITS application.

Background Many studies have shown effects of anodal transcranial direct current stimulation (a-tDCS) and high-frequency transcranial random noise stimulation (tRNS) on elevating cortical excitability. Moreover, tRNS with a direct current (DC)-offset is more likely to lead to increases in cortical excitability than solely tRNS. While a-tDCS over primary motor cortex (M1) has been shown to attenuate pain perception, tRNS + DC-offset may prove as an effective means for pain relief. Objective This study aimed to examine effects of a-tDCS and high-frequency tRNS + DC-offset over M1 on pain expectation and perception, and assess whether these effects could be influenced by the certainty of pain expectation. Methods Using a double-blinded and sham-controlled design, 150 healthy participants were recruited to receive a single-session a-tDCS, high-frequency tRNS + DC-offset, or sham stimulation over M1. The expectation and perception of electrical stimulation in certain and uncertain contexts were assessed at baseline, immediately after, and 30 min after stimulation. Results Compared with sham stimulation, a-tDCS induced immediate analgesic effects that were greater when the stimulation outcome was expected with uncertainty; tRNS induced immediate and sustained analgesic effects that were mediated by decreasing pain expectation. Nevertheless, we found no strong evidence for tRNS being more effective for attenuating pain than a-tDCS. Conclusions The analgesic effects of a-tDCS and tRNS showed different temporal courses, which could be related to the more sustained effectiveness of high-frequency tRNS + DC-offset in elevating cortical excitability. Moreover, expectations of pain intensity should be taken into consideration to maximize the benefits of neuromodulation.

Objective Many studies have examined the effectiveness of transcranial direct current stimulation (tDCS) on human pain perception in both healthy populations and pain patients. Nevertheless, studies have yielded conflicting results, likely due to differences in stimulation parameters, experimental paradigms, and outcome measures. Human experimental pain models that utilize indices of pain in response to well-controlled noxious stimuli can avoid many confounds present in clinical data. This study aimed to assess the robustness of tDCS effects on experimental pain perception among healthy populations. Methods We conducted three meta-analyses that analyzed tDCS effects on ratings of perceived pain intensity to suprathreshold noxious stimuli, pain threshold and tolerance. Results The meta-analyses showed a statically significant tDCS effect on attenuating pain-intensity ratings to suprathreshold noxious stimuli. In contrast, tDCS effects on pain threshold and pain tolerance were statistically non-significant. Moderator analysis further suggested that stimulation parameters (active electrode size and current density) and experimental pain modality moderated the effectiveness of tDCS in attenuating pain-intensity ratings. Conclusion The effectiveness of tDCS on attenuating experimental pain perception depends on both stimulation parameters of tDCS and the modality of experimental pain. Significance This study provides some theoretical basis for the application of tDCS in pain management.

Reduced empathy and elevated alexithymia are observed in autism spectrum disorder (ASD), which has been linked to altered asymmetry in brain morphology. Here, we investigated whether trait autism, empathy, and alexithymia in the general population is associated with brain morphological asymmetry. We determined left–right asymmetry indexes for cortical thickness and cortical surface area (CSA) and applied these features to a support-vector regression model that predicted trait autism, empathy, and alexithymia. Results showed that less leftward asymmetry of CSA in the gyrus rectus (a subregion of the orbitofrontal cortex) predicted more difficulties in social functioning, as well as reduced cognitive empathy and elevated trait alexithymia. Meta-analytic decoding of the left gyrus rectus annotated functional items related to social cognition. Furthermore, the link between gyrus rectus asymmetry and social difficulties was accounted by trait alexithymia and cognitive empathy. These results suggest that gyrus rectus asymmetry could be a shared neural correlate among trait alexithymia, cognitive empathy, and social functioning in neurotypical adults. Left–right asymmetry of gyrus rectus influenced social functioning by affecting the cognitive processes of emotions in the self and others. Interventions that increase leftward asymmetry of the gyrus rectus might improve social functioning for individuals with ASD.

Introduction: Pantoea dispersa belongs to the genus Pantoea, which is isolated from Enterobacteriaceae. It has been reported to cause some kinds of infections, but there are few detailed studies on it, especially its characteristics and identification methods, which has caused a lot of trouble in clinical work. Patient concerns: A 51-year-old Chinese man was admitted to our hospital with a 7-hour history of progressive abdominal pain. He was previously diagnosed with liver cirrhosis secondary to chronic hepatitis B infection and hepatocellular carcinoma. An emergency hepatic artery embolization for hemostasis was performed under local anesthesia. Forty-eight hours later, the patient presented sudden onset of high fever up to 39.0 °C and chill. Diagnosis: Morphological and phenotypic profiles were performed for preliminary identification for P dispersa. The biochemical features were obtained by VITEK 2 Test Kit. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis and 16S ribosomal RNA sequencing were performed to accurately identify P dispersa. Intervention: Antibiotic therapy of intravenous ceftazidime was started empirically. The antibiotic treatment was switched to intravenous cefepime at the same time because of suspected ceftazidime treatment failure and microbiological sensitivity. Outcomes: The patient remained afebrile, and the second blood culture results were negative. Chest X-ray was normal as well. In order to control the progression of the hepatic lesion, transarterial chemoembolization was performed under local anesthesia. After completion of 14 days of antibiotic treatment, the patient was discharged with no signs of recurrence. Conclusion: P dispersa, a gram-negative bacterium rod, were facultative anaerobic, which displayed yellow pigmentation, round, raised, smooth on culture plates. Conventional analysis was difficult to complete its identification. With biochemical tests, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis and 16S ribosomal RNA sequencing, P dispersa can be accurately identified. It will help physicians understand the related clinical manifestations and make timely and effective treatment for patients.

Nickel-based superalloys have been widely used to produce high-performance components in advanced engines. In present research, isothermal compression tests of GH4065A nickel-based superalloy were conducted at deformation temperatures of 1020–1140 °C and strain rates of 0.001–1.0 s−1. The deformation temperature and strain rate have a significant effect on the flow curves, from which the intrinsic connection between the flow stress and deformation behavior can be systematically investigated. The deformation activation energy of the studied alloy was calculated to be 521.65 kJ·mol−1 at the strain of 0.5 when the flow stress was steady. Meanwhile, the constitutive equation was constructed for modeling the hot plastic deformation, and the prediction accuracy of flow stress was well verified. Based on the combination of processing map and microstructural observation, two instability domains were delineated as follows: Domain #1: 1020–1065 °C/0.25–1.0 s−1; Domain #2: 1130–1140 °C/0.001–0.002 s−1. In addition, the instability mechanism of these two domains was deeply discussed. The results obtained in this research would provide effective theoretical guidance for manufacturing high-performance components in advanced engines.

The characteristic flow behaviour of the γ + γ′ duplex structure during the thermomechanical processing (TMP) of highly alloyed disc alloys was comprehensively investigated. Based on the TMP of the γ + γ′ duplex, a series of promising techniques for the billet conversion and microstructure customization can be developed. The superplasticity of γ + γ′ duplex was confirmed by tensile tests, and the optimum combination of temperature and strain rate was determined. For a certain alloy, the maximum elongation up to more than 1000% can be achieved at the temperature of equilibrium γ′ solvus minus 100 °C. Near net shape forgings can be produced within this temperature region. During conversion of the VAR ingots, a proper TMP can trigger a discontinuous precipitation instead of the dynamic strain ageing effect which usually leads to a drastic degradation of plasticity. Therefore, the processing window of ingot conversion can be greatly broadened. Producing the dual microstructure disc forging using TMP from a γ + γ′ duplex billet exhibits the inherent advantages over standard heat treatment techniques. The grain size of coarse-grained region can be continuously modulated by controlling the local plastic strain, and the location of the interface between the coarse-grained region and fine-grained region can be precisely determined by controlling the strain distribution. The multi-cycle TMP techniques can play a constructive role in the conversion of the as-HIP billets of P/M material. By producing the γ + γ′ microduplex, prior particle boundaries (PPBs) and inclusions can be efficiently broken up during TMP. As a result, the hot working ductility and the quality of the ultrasonic inspections can be greatly improved.

Bacteroides caccae is an anaerobic bacterium with a reportedly high isolation rate; however, it rarely causes bloodstream infections. Patients with hypertension are at increased risk of developing anaerobic bacterial infection. In this study, we report a case of bacteremia caused by B. caccae in a patient with renal hypertension and gastrointestinal hemorrhage. This study describes the clinical manifestations of bloodstream infection involving B. caccae to provide guidance for laboratory technicians and clinicians. A 42-year-old Chinese man was admitted for gastrointestinal hemorrhage and subsequently diagnosed with anaerobic blood infection. The pathogenic bacteria isolated from anaerobic blood culture bottles were identified as B. caccae by using an automatic bacterial identification instrument and mass spectrometry (MS). B. caccae is an intestinal opportunistic pathogen that can invade the intestinal mucosa and cause anaerobic bloodstream infection. Two or more sets of blood cultures and MS identification can greatly improve the positive detection rate of blood cultures of anaerobic bacteria. Furthermore, the increased drug resistance of anaerobic bacteria necessitates drug sensitivity tests for anaerobic bacteria in many hospitals. Thus, the early prevention and control of primary diseases with appropriate diagnoses and timely anti-infection therapies are necessary to reduce B. caccae bloodstream infection.

The development of equipment and technology makes it possible to manufacture a O2000 mm Alloy 706 disc 800 MN hydraulic press in China. Generally, high temperature or low strain rate is needed during the closed-die forging process to lower the requirement for press capacity; however, it will result in coarse unrecrystallized grains which are not beneficial for mechanical properties. In the investigation of hot deformation behavior by thermo-simulation compression tests in Alloy 706, it is found that abnormal dynamic recrystallization (DRX) behavior occurs in a high temperature and low strain rate condition. Electron backscatter diffraction (EBSD) investigation indicates that the fraction of twin boundaries in the abnormal microstructure is 80% lower than that in the normal microstructure, and apparent texture can be detected. Subscale disc forging experiments were carried out to investigate the effects of abnormal microstructure on mechanical properties of Alloy 706. The microstructure evolution mechanism of abnormal DRX is validated and the influence on mechanical properties is discussed.

The aim of the present study was to investigate the effect of the pH level on the reinforcement of Zn-fused ceramic whisker composites. Zinc oxide (ZnO)-fused aluminum borate whiskers (AlBw) were used to strengthen dental resin composites, and the pH level was found to be a pivotal parameter that determined the composite strength. Another purpose of this study was to investigate the effect of the pH level on the bending strength, elastic modulus, compressive strength and hardness of the composites at pH = 6.0, pH = 6.2, pH = 6.4, pH = 6.6 and pH = 6.8. Each mixture was thermally fused, then silanized and combined with a dental resin at a filler mass percentage of 50%. X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy were employed to characterize and analyze the AlBw, the ZnO-AlBw and the fracture surface of the resin composites. The highest bending strength (MPa) was observed for the group with pH = 6.4 (140.58 ± 12.86, n = 5), and the minimal bending strength was observed for the group with unmodified AlBw (73.20 ± 6.12, n = 5). The compressive strength and bending strength were the opposite, the group with unmodified AlBw was highest (332 ± 40, n = 5), and the group with pH = 6.4 was lowest (298 ± 20, n = 5). Reinforcement with ZnO-fused AlBw resulted in novel dental resin composites that possessed a bending strength higher than the unmodified whiskers.

Postoperative infections remain a risk factor that leads to failures in oral and maxillofacial artificial bone transplantation. This study aimed to synthesize and evaluate a novel hydroxyapatite whisker (HAPw) / nano zinc oxide (n-ZnO) antimicrobial bone restorative biomaterial. A scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD) were employed to characterize and analyze the material. Antibacterial capabilities against Staphylococcus aureus, Escherichia coli, Candida albicans and Streptococcus mutans were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), and kinetic growth inhibition assays were performed under darkness and simulated solar irradiation. The mode of antibiotic action was observed by transmission electron microscopy (TEM) and confocal laser scanning microscopy (CLSM). The MIC and MBC were 0.078-1.250 mg ml(-1) and 0.156-2.500 mg ml(-1), respectively. The inhibitory function on the growth of the microorganisms was achieved even under darkness, with gram-positive bacteria found to be more sensitive than gram-negative, and enhanced antimicrobial activity was exhibited under simulated solar excitation compared to darkness. TEM and CLSM images revealed a certain level of bacterial cell membrane destruction after treatment with 1 mg ml(-1) of the material for 12 h, causing the leakage of intracellular contents and bacteria death. These results suggest favorable antibiotic properties and a probable mechanism of the biomaterial for the first time, and further studies are needed to determine its potential application as a postoperative anti-inflammation method in bone transplantation.

The antibacterial activity of zinc oxide (ZnO) and the strengthening of hydroxylapatite whiskers (HAPws) have been widely studied and applied. However, the antibacterial properties of ZnO–HAPws have scarcely been researched. The aim of this study was to further investigate several types of nano-ZnO morphologies of ZnO–HAPws that were prepared using the sol–gel method at different pondus hydrogenii (pH) values and temperatures. The four morphologies of ZnO–HAPws that were investigated here were granule, triangle, short rod and disc type, and these morphologies were investigated at 70 °C at pH 6.4, 37 °C at pH 6.6, 70 °C at pH 6.6 and 70 °C at pH 6.6, respectively. Next, the antibacterial activity of ZnO–HAPw was compared to that of nano-ZnO, commercially available ZnO and tetrapod-like ZnO whiskers (T-ZnOw) with six bacteria that are associated with oral infections: Streptococcus mutans, Lactobacillus casei, Candida albicans, Actinomyces viscosus, Staphylococcus aureus and Escherichia coli. The results of examinations of the minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) showed that the antibacterial activity of ZnO–HAPw exceeded that of the commercially available ZnO and T-ZnOw. Additionally, analysis of variance (ANOVA) analysis of the MBCs revealed that the four tested antibacterial agents had significantly different effects on S. mutans (F = 8.940; P = 0.006), S. aureus (F = 6.924; P = 0.013) and E. coli (F = 4.468; P = 0.04). ANOVA analyses of the MICs revealed that the four tested antibacterial agents had significantly different effects on S. mutans (F = 6.183; P = 0.018), A. viscosus (F = 4.531; P = 0.039) and S. aureus (F = 18.976; P = 0.001).

The present paper is aimed to discuss the influence of three different ways on modification of aluminum borate whiskers (AlBw) and on flexural properties of dental composite resins. In Group A, AlBw and silicon dioxide (SiO2) nanoparticles were thermally fused directly under certain processes. In Group B, Si-O network was formed on the surface of AlBw via the sol-gel process of tetraethoxysilane, then thermally fused with SiO2 nanoparticles to form AlBw-SiO2 compound as inorganic fillers. In Group C, SiO2 nanoparticles were repaired by sol-gel method of tetraethoxysilane under certain processes, and were deposited in the surface of AlBw. The mixtures were fused with high temperature sintering method. The effects of the surface morphology of AlBw with different ways were characterized by TEM and SEM. Then the mixtures were polymerized with resin matrix after surface siliconization and their flexural strength and Young's modulus were determined. SEM was used to examine specimen fracture surfaces. The results showed that the flexural properties of dental composite resins were significantly improved after whiskers were modified. Different methods produce different effects. Flexural strength of the Group A is (95.28 +/- 4.53) MPa. The results of TEM and SEM revealed that the aggregation was obvious between AlBw and SiO2 nanoparticles. Flexural strength of the Group B was (123.14 +/- 17.37) MPa. The results of TEM and SEM revealed that the dispersity was improved but SiO2 nanoparticles also reunited. AlBw were modified with nanometer-size SiO2 particles which were prepared by sol-gel method based on tetraethyl orthosioate (TEOS), the flexural properties of a new type of dental composite resins was (130.29 +/- 8.38) MPa. The results of TEM and SEM revealed that better dispersion between AlBw and SiO2 nanoparticles occurred. The SiO2 nanoparticles were fused and attached onto the surface of AlBw uniformly.

The favorable biocompatibility of dental biomaterial is very important, which guarantees the safety and effectiveness of its clinical application. The cytotoxicity test, as one of the biological evaluation screening tests, is known to be an important and frequently used method to evaluate biocompatibility of biomaterials. This text is devoted to an overview of the cytotoxicity test for dental materials.