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In the present study, the Surface-enhanced Raman Spectroscopy (SERS)-based metabolomics approach coupled with chemometrics was developed to determine the geographic origins of Keemun black tea. The SERS peaks enhanced by Ag nanoparticles at Δv = 555, 644, 731, 955, 1240, 1321, and 1539 cm− 1 were selected, and the intensities were calculated for chemometric analysis. Linear discriminant analysis (LDA) presented an average discrimination accuracy of 86.3%, with 84.3% cross-validation for evaluation. The recognition of three machine learning algorithms, namely feedforward neural network (FNN), random forest (RF), and K-Nearest Neighbor (KNN), for black tea were 93.5%, 93.5%, and 87.1%, respectively. Herein, this study demonstrates the potential of the SERS technique coupled with AgNPs and chemometrics as an accessible, prompt, and fast method for discriminating the geographic origins of teas.

Actinide (Th and U) carbides as the potential nuclear fuels in nuclear reactors require basic research in order to understand the thermodynamic stability and performance of these substances. Here we report the structural characterization and bonding analyses of [C

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The purpose of this prospective study was to investigate the 4-year outcome and prognostic factors of nonsurgical root canal retreatment determined by measuring the volumetric change of periapical radiolucencies on cone-beam computed tomographic (CBCT) scans.Ninety-seven endodontically treated teeth from 80 patients diagnosed as apical periodontitis and indicated for root canal retreatment were included. Retreatment was performed by 7 endodontic specialists using a standardized treatment protocol. The teeth were reexamined clinically and radiographically 48-67 months after retreatment. The volume of preoperative and postoperative periapical radiolucencies on CBCT images was independently measured by 2 examiners. Radiographic outcome is presented in 4 categories: absence, reduction, enlargement, or unchanged. Reduction or enlargement was determined when the volumetric change of radiolucency was 20% or more. Multivariate logistic regression was performed for predictor analysis.Sixty-two teeth (63.9%) from 50 patients returned for follow-up. Fifty-eight teeth were included in the prognostic analysis, all of which were symptom free. The 4 remaining teeth that had been extracted because of fracture were excluded. The total volume of periapical radiolucencies at 4 years postoperatively decreased by 94.6% compared with that preoperatively (P.001), with an average reduction of 83.4% (95% confidence interval, 69.2%-97.5%). The periapical radiolucencies were determined as absence in 44 teeth (75.9%), reduction in 10 teeth (17.2%), unchanged in 1 tooth (1.7%), and enlargement in 3 teeth (5.2%). Tooth type was identified as an outcome predictor (P.05).The 4-year outcome of endodontic retreatment is predictable, with a significant volumetric reduction in periapical radiolucencies.

This study developed a simple, rapid, stable, and reliable technique for acrylamide (AAm) detection through surface-enhanced Raman scattering (SERS) on an AgNPs substrate with an aggregating agent. Specifically, the agglomeration effects of five types of salt solutions (NaCl, KCl, MgCl

Geographic-label is a remarkable feature for Chinese tea products. In this study, the UHPLC-Q/TOF-MS-based metabolomics approach coupled with chemometrics was used to determine the five narrow-geographic origins of Keemun black tea. Thirty-nine differentiated compounds (VIP 1) were identified, of which eight were quantified. Chemometric analysis revealed that the linear discriminant analysis (LDA) classification accuracy model is 91.7%, with 84.7% cross-validation accuracy. Three machine learning algorithms, namely feedforward neural network (FNN), random forest (RF) and support vector machine (SVM), were introduced to improve the recognition of narrow-geographic origins, the performances of the model were evaluated by confusion matrix, receiver operating characteristic curve (ROC) and area under the curve (AUC). The recognition of RF, SVM and FNN for Keemun black tea from five narrow-geographic origins were 87.5%, 94.44%, and 100%, respectively. Importantly, FNN exhibited an excellent classification effect with 100% accuracy. The results indicate that metabolomics fingerprints coupled with chemometrics can be used to authenticate the narrow-geographic origins of Keemun black teas.

To solve the problem of abnormal angular velocity and angular acceleration in manipulator trajectory motion controlled by quintic spline interpolation algorithm, a manipulator trajectory control algorithm combined with moving average filtering algorithm was proposed. Based on the quintic spline interpolation algorithm, the moving average filtering algorithm was used to clean the abnormal data under the quintic spline interpolation. And the recursive forward dynamics model based on joint space motion was used to design the trajectory motion control of the manipulator. The simulation results show that the manipulator trajectory control algorithm combined with the moving average filtering algorithm has strong constraint ability of diagonal velocity and angular acceleration, and 67% of the maximum velocity and maximum acceleration of the joint axis of the designed manipulator trajectory are significantly reduced, and the curve is smoother.

Objective To explore the function and mechanism of related genes in the occurrence and development of liver cancer, and the possibility of key genes as potential biomarkers and prognostic indicators for the treatment of liver cancer.Methods We selected 4 datasets(GSE57957, GSE121248, GSE36376 and GSE14520)from the GEO database.With

While polymer extended-chain crystals (ECCs) own promising physicochemical properties, effective product and application of ECCs is still challenging. Here, we develop an industrializable and sustainable production procedure process for ECCs of poly(butylene succinate) (PBS), which consists of a specially-designed melt mixing of the polymer and urea in internal mixer to produce inclusion complex and thereafter a washing step with water. The prepared ECCs show melting point at 137 °C and crystallinity higher than 90%, and the auxiliary materials, urea and water, can be recycled. The ECCs are further used as highly effective nucleating agent and reinforcer for commercial PBS, resulting in remarkable simultaneous increases in crystallization temperature, yield stress and elongation at break due to the perfect lattice matching and interfacial compatibility. Moreover, a shape memory material of single component of PBS has been fabricated with the in-situ addition of ECCs.

Chronic atrophic gastritis (CAG) is a common digestive disease in clinic. Previous experimental and clinical studies have shown that acupuncture has a positive effect for CAG. Apoptosis of gastric mucosal tissue has been shown to play an important role in the process of gastric atrophy and possibly further carcinogenesis in CAG, and the circular RNA (circRNA), a novel class of non-coding RNA, has been confirmed to play a regulatory role in the downstream pathway of apoptosis by many stu-dies. Accumulated findings of experimental studies showed that acupuncture and moxibustion interventions could suppress apoptosis of the cultured human gastric mucosal epithelial cells and lower apoptotic index of gastric mucosal cells in CAG rats. Therefore, circRNA is likely to mediate the inhibitory effect of acupuncture and moxibustion on apoptosis of gastric mucosal epithelial cells in CAG. In this paper, we systematically summarized 1) the regulation of circRNA on apoptosis, 2) the apoptosis and pathological mechanism of CAG, 3) the effect of acupuncture on apoptosis, and proposed that circRNA is highly likely to be involved in the positive effect of acupuncture and moxibustion interventions for CAG. It is recommended that researches should further reveal the scientific basis of acupuncture and moxibustion therapies in the treatment of CAG by exploring the role of related circRNAs and their downstream target proteins in the gastric mucosal tissues.

Circadian rhythms play an important role in a wide range of human physiology and pathology. Individuals increasingly experience situations such as night-shift work schedules, likely leading to circadian disruption. Recent studies have also demonstrated that patients with other diseases often show symptoms of circadian disruption as manifested by the sleep-wake cycle and other biological rhythms. Circadian disruption often results in changes to the phase, period, and amplitude of the sleep-wake cycle, melatonin rhythm, and core body temperature. Several cardiometabolic, psychiatric, and neurodegenerative diseases are closely related to circadian disruption. Several interventions are also available, including phototherapy, exogenous melatonin, and exercise. The cumulative findings suggest that circadian disruption can increase risk for some cardiometabolic diseases. Circadian disruption also acts as a concomitant symptom of several psychiatric and neurodegenerative diseases. More attention should be paid to evaluating the impact of circadian disruption on these related diseases, as well as the benefits of the mitigation interventions for both circadian disruption and related diseases.

To compare the clinical therapeutic effect on post-stroke spastic paralysis of the upper extremity between the combination of kinematic-acupuncture therapy and rehabilitation training and the combined treatment of the conventional acupuncture with rehabilitation training.A total of 60 patients of post-stroke spastic paralysis of the upper extremity at the non-acute stage were randomized into an observation group (30 cases) and a control group (30 cases, 1 case dropped off). On the base of the routine western medication and rehabilitation treatment, the kinematic-acupuncture therapy was added in the observation group and the conventional acupuncture was used in the control group. Baihui (GV 20), Dazhui (GV 14), Jiaji (EX-B 2) from TCompared before treatment, in 7 and 14 days of treatment, FMA-UE score was increased obviously in either group (For the patients with post-stroke spastic paralysis of the upper extremity at the non-acute stage, the combined treatment with kinematic-acupuncture therapy and rehabilitation training obviously improves the motor function of the upper extremity and the muscle tone of elbow joint and metacarpophalangeal joint. The therapeutic effect of this combination is better than that of the combined treatment of the conventional acupuncture with rehabilitation training. Additionally, this combined therapy improves the ability of daily life activity.

We successfully use a co-precipitation method to prepare inclusion complex between poly(butylene adipate) (PBA) chains (guest component) and urea molecules (host component). The PBA/urea inclusion complex is confirmed to adopt a hexagonal crystal modification with lattice parameters of a = 8.14 A and c = 10.92 A, and the interaction between PBA chains and urea is van der Waals force. The singly isolated PBA chains are suggested to take some gauche conformation, which is different from the all-trans conformation in β-form PBA. Furthermore, we employ the isolated PBA chains which are uniformly pre-established in a specific conformation in urea channels to regulate the crystal form of PBA for the first time. After removing the host urea molecules, the coalesced PBA chains are found to solely crystallize into α-form crystals at different coalescing temperatures. By comparing the FTIR spectra, it is found that PBA chains in inclusion complex plausibly contain some similar conformers as those in α-form crystal, which is suggested to be the intrinsic reason for the sole formation of α-form crystals. This research proves that inclusion complex can be used as a very effective method to regulate polymorphism of semi-crystalline polymers.

The detailed structure and crystallization behavior of poly(butylene succinate) (PBS) have been investigated by Fourier transform infrared (FTIR) and other methods systematically. For the first time, we confirmed that the C═O stretching modes of PBS can respond to three distinguish absorption bands in the FTIR spectrum, at around 1736, 1720, and 1714 cm–1 respectively. The 1736 cm–1 band is adopted as the stretching mode of C═O groups in free amorphous fraction (MAF); the 1714 cm–1 band which is relevant to more stable structure, displays more anisotropic in polarized FTIR spectra, and has been confirmed as stretching vibrations of hydrogen-bonded C═O groups in the crystalline phase. The 1720 cm–1 band is linked to crystallization but comes from less ordered structure. Moreover, the 1720 cm–1 band can be destroyed prior to 1714 cm–1 band during heating and constructed behind 1714 cm–1 band during cooling. Thus, the 1720 cm–1 band is reasonably ascribed to the C═O groups in rigid amorphous fraction (RAF) o...

We successfully developed an effective strategy for preparing poly(butylene succinate) (PBS) material with exceptionally high crystallinity (94.4% from density data) and melting point (∼136 °C) from its urea inclusion complex under normal air pressure for the first time. The strategy consists of three steps: co-electrospinning PBS with urea, thermal treatment, and coalescence of PBS in water. Electrospinning provides well physical mixing between PBS and urea. Thermal treatment causes the assembly of PBS and urea and leads to formation of their inclusion complex, in which PBS chains are separately isolated in urea channels. During the coalescing process the isolated and ordered PBS chains formed crystals with lamellar thickness larger than 26 nm—larger than 5-fold of common PBS crystal—after removing host urea frames. PBS crystals obtained with such high crystallinity and melting point are proved to be the extended-chain crystals (ECCs). Comparative study reveals that the electrospinning and thermal treatm...

Acute alcohol exposure induces unconscious condition such as coma whose main physical manifestation is the loss of righting reflex (LORR). Xingnaojing Injection (XNJI), which came from Chinese classic formulaAn Gong Niu HuangPill, is widely used for consciousness disorders in China, such as coma. Although XNJI efficiently shortened the duration of LORR induced by acute ethanol, it remains unknown how XNJI acts on ethanol-induced coma (EIC). We performed experiments to examine the effects of XNJI on orexin and adenosine (AD) signaling in the lateral hypothalamic area (LHA) in EIC rats. Results showed that XNJI reduced the duration of LORR, which implied that XNJI promotes recovery form coma. Microdialysis data indicated that acute ethanol significantly increased AD release in the LHA but had no effect on orexin A levels. The qPCR results displayed a significant reduction in the Orexin-1 receptors (OX1R) expression with a concomitant increase in the A1receptor (A1R) and equilibrative nucleoside transporter type 1 (ENT1) expression in EIC rats. In contrast, XNJI reduced the extracellular AD levels but orexin A levels remained unaffected. XNJI also counteracted the downregulation of the OX1R expression and upregulation of A1R and ENT1 expression caused by EIC. As for ADK expression, XNJI but not ethanol, displayed an upregulation in the LHA in EIC rats. Based on these results, we suggest that XNJI promotes arousal by inhibiting adenosine neurotransmission via reducing AD level and the expression of A1R and ENT1.

Low-loss planar and channel waveguides in ${\rm Pr}^{3+}$ -doped yttrium orthosilicate single crystals were fabricated using 6-MeV oxygen ion implantation. The fabricated surface guiding structure was characterized by the prism coupling method. The relationship between the implantation induced index change and the implantation fluence has been investigated. The photoluminescence properties of the implanted samples were found to be well preserved with respect to the bulk, exhibiting possible applications for integrated quantum memory and laser generation devices.

Cyclodextrin glycosyltransferase (CGTase) is an enzyme able to convert starch and other substrates into cyclodextrins (CDs). A marine strain Y112 producing α-CGTase was identified as Bacillus agaradhaerens Y112 by physiological and biochemical characterization, and 16S rDNA analysis. The gene coding for α-CGTase was cloned, sequenced and expressed in Escherichia coli BL21 (DE3) cells. Recombinant α-CGTase was purified in one-step chromatographic separation and its purity evaluated by SDS-PAGE, showing the presence of one band with a molecular mass of about 92 kDa. Additionally, enzymatic capability was analyzed by measuring the starch conversion, and resulted in about 45% of CDs obtained after 6 h of cyclodextrin reaction. Of these CDs, mainly α-CD was produced (70% of the total CDs yield), suggesting the potential of this CGTase for industrial applications.

Accurate calibration of aerosol measurement instruments is critical for ensuring the data quality when sampling ambient particulate matter (PM) or those from emission sources. A system for calibrating these instruments was set up, which included an ultrasonic device to generate polydisperse supermicron particles, a chamber, and an aerodynamic particle spectrometer to measure particle size distribution. We verified its performance in stably generated testing aerosol with good spatial uniformity, controlled size distributions and concentrations. The testing aerosol generated had a lognormal distribution. A PM₁₀ and PM₂.₅ two-stage virtual impactor was calibrated using this online method. Collection efficiencies of PM₁₀ and PM₂.₅ stages calibrated by an off-line method using monodisperse particles were also used for comparison. The results from two different methods were consistent with each other. Though the off-line method has been widely used to calibrate PM samplers, it suffers from long experimental duration (2-3 days for calibrating one sampler). In contrast, the online method allows for a rapid calibration (less than half a day for calibrating one sampler).

China does not have a national standard method for stationary source PM10 and PM2.5 sampling. Current commercial PM10/PM2.5 samplers have some limitations when used in China. In this study, we developed a two stage virtual impactor for sampling PM10/PM2.5 from stationary source. Its performance was evaluated using laboratory generated aerosol. Its collection efficiency curve satisfies the requirement of ISO 7708:1995 for PM10/PM2.5 samplers. The diameter of this cylindrical virtual impactor is 74 mm, smaller than the diameter of the sampling port in most stationary sources in China. Both filter papers and filter thimbles can be used with this impactor which makes it suitable for both low and high dust concentration sampling. The ratio of the minor flowrate to the total flowrate influences the cutoff size (D50) of the virtual impactor. Reducing this ratio will lead to an increase in D50. The distance from the bottom of the accelerating nozzle to the top of the collecting nozzle should be greater than 1.5-2.0 times the diameter of the accelerating nozzle.

Neuroprotective strategies following cardiopulmonary resuscitation (CPR) are an important focus in emergency and critical care medicine. Matrix metalloproteinases (MMPs), especially MMP9 attracted much attention because of its function in focal brain ischemia/reperfusion injury. In the focal cerebral ischemia model in rats, SB-3CT can suppress the expression of MMP9, relieving brain edema, and there was no studies on global cerebral ischemia-reperfusion injury after CPR.One hundred and twenty rats were randomly assigned to sham-operated (n = 40), resuscitation treatment (n = 40), and resuscitation control (n = 40) groups. Sham-operated group rats were anesthetized only and intubated tracheally, while the resuscitation treatment and resuscitation control groups also received cardiac arrest by asphyxiation. In the resuscitation treatment group, SB-3CT was injected intraperitoneally after restoring spontaneous circulation (ROSC), defined as restoration of supraventricular rhythm and mean arterial pressure (MAP)or = 60 mm Hg for more than 5 minutes. The resuscitation control group also implemented ROSC without injection of SB-3CT. The rats were executed and samples were taken immediately after death, then at 3, 9, 24, and 48 hours (n = 8). Brain tissue expression of MMP9 protein, MMP9 mRNA, water content, Evans blue content, TNF-alpha, IL-1, and IL-6 was measured, and the brain tissue ultramicrostructure studied with electron microscopy.In the resuscitation control group, brain tissue expression of MMP9 protein and mRNA, water content, Evans blue content, TNF-alpha, IL-1, and IL-6 were significantly elevated at 3 hours, and peaked at 24 hours after resuscitation, when compared with the sham-operated group (P0.05). Tissue ultramicrostructure also changed in the resuscitation control group. By contrast, although all these indexes were increased in the resuscitation treatment group compared with the sham-operated group (P0.05), they were lower than in the resuscitation control group (P0.05).Expression of MMP9 protein and mRNA, water content, Evans blue content, TNF-alpha, IL-1, and IL-6 increased in rat brain tissue after CPR, indicating disruption of the blood-brain barrier and excess inflammatory reaction. MMP9 expression was reduced with SB-3CT, resulting in reduced brain injury.

Over-expression of matrix metalloproteinase 9(MPP 9) in brain could degrade extracellular matrix, destroy the structure of microvascular basal membrane and vascular wall, take part in neural- inflammatory response in a rat model of cardiopulmonary resuscitation (CPR). SB-3CT is a antagonist of MPP 9. SB-3CT can inhibit over-expression of MPP 9 and reduce impairment of brain in a rat model of CPR. One hundred and twenty rats were randomly divided into 3 groups: the sham-operated group, the resuscitation control group and the resuscitation treatment group with SB-3CT. The rats were executed and the brains were taken out at 0h, 3h, 9h, 24h and 48h. The expression of MMP 9 in brain was detected. Water content and Evans blue content in brain tissue were observed. The expression of MMP 9 (Table 1 ), water content and Evans blue content in the resuscitation control group was obviously higher than the sham-operated group at 0h, 3h, 9h, 24h and 48h. The expression of MMP 9, water content and Evans blue content in the resuscitation treatment group was similar to the resuscitation control group at different time, but the level was lower than the resuscitation control group(p Table 1 Expression of brain MMP 9 after resuscitation in a rat model of CPR

To compare the efficacy of preemptive epidural analgesia combined with postoperative epidural analgesia, postoperative epidural analgesia alone and intravenous analgesia for postoperative pain relief and their effects on plasma interleukin-6 (IL-6) concentration following radical surgery for gastric carcinoma.Sixty-six patients with gastric carcinoma scheduled for gastrectomy were randomly divided into 3 groups, namely group P (n=22), group E (n=22) and group V (n=22), to receive preemptive epidural analgesia combined with postoperative epidural analgesia, exclusive postoperative epidural analgesia, and exclusive postoperative intravenous analgesia, respectively. Hemodynamic data were recorded for all the patients during the operation, and visual analogue scale (VAS) was used to assess the pain intensity at 4, 8, 16, 24, 48 and 72 h after surgery. Plasma IL-6 concentration was determined before surgery and at 24, 48, 72 h after surgery.No significant changes occurred in the hemodynamics during the preoperative periods. VAS and IL-6 were lower in group P than in group E and V, and group E had lower measurement than group V (P0.05).Preemptive epidural analgesia combined with postoperative epidural analgesia provides more satisfactory pain relief and more effectively prevents IL-6 increment than exclusive epidural analgesia or intravenous analgesia after gastrectomy for gastric carcinoma.