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1.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Article in English | MEDLINE | ID: mdl-38081273

ABSTRACT

The electromagnetic interference (EMI) around the devices for ionizing radiation experiments is a serious concern. In order to reduce EMI and enhance the signal-to-noise ratio, a new type of analog fiber optic link (FOL) has been developed for fast pulse signal transmission under complicated electromagnetic fields. Electrical signals are converted to optical signals through an electro-optical conversion process using the amplitude modulation mechanism. After long-distance transmission, optical signals can also be restored via photoelectric conversion. Each link has a transmitter unit connected via a fiber optic cable to the receiver unit. The transmitter unit consists of a distributed feedback laser, a driver circuit made of amplifiers, and an automatic temperature control module, while the receiver unit consists of a PIN detector, a transimpedance amplifier, a main amplifier, and a third order active low-pass filter. A prototype of this link has been fabricated and tested. The test results show that the transmission bandwidth of the analog signals is DC ∼ 155 MHz, the transmission delay is a typical 21 ns, the linear dynamic range is greater than 56 dB (692 times larger), the output noise is less than 4.5 mV, and the transmission distance is up to several kilometers, which can meet the requirements of ionizing radiation experiments. The FOL demonstrates great performance in transmission for scientific research with high quality in terms of transmission bandwidth, linearity, security, and stability.

2.
J Nutr Health Aging ; 27(8): 649-655, 2023.
Article in English | MEDLINE | ID: mdl-37702338

ABSTRACT

OBJECTIVES: Frailty has become an independent risk factor for adverse outcomes in critically ill patients. This study aimed to explore the predictive ability of two electronic medical record-based frailty assessment tools, the Hospital Frailty Risk Score (HFRS) and Frailty Index based on physiological and laboratory tests (FI-lab), for long-term adverse prognosis in older critically ill survivors. DESIGN: Retrospective observational study. SETTING AND PARTICIPANTS: 9,082 critically ill survivors aged ≥ 65 years. MEASUREMENTS: The HFRS and the 33-item FI-lab were constructed based on the published literature. Cox and logistic regression models assessed the association between frailty and 1-year mortality and post-discharge care needs. RESULTS: 2,586 patients died within 1 year of follow-up. In fully adjusted models, frailty assessed using both the HFRS (per point, hazard ratio [HR] 1.06, 95% confidential interval [CI] 1.05-1.06; intermediate frailty risk, HR 2.00, 95% CI 1.78-2.25; high frailty risk, HR 3.06, 95% CI 2.68-3.50) and FI-lab (per 0.01 points, HR 1.03, 95% CI 1.03-1.03; intermediate frailty risk, HR 1.59, 95% CI 1.44-1.76; high frailty risk, HR 2.30, 95% CI 2.06-2.57) was associated with mortality. Addition of frailty indicators improved the predictive validity of the Sequential Organ Failure Assessment score for mortality (HFRS alone ∆ C-index 0.034; FI-lab alone ∆ C-index 0.016; HFRS and FI-lab combined ∆ C-index 0.042). The HFRS but not the FI-lab was associated with higher probability of post-discharge care needs. CONCLUSION: Both the HFRS and FI-lab could independently predict 1-year mortality in older critically ill survivors. Adding the HFRS to the SOFA score model improved it more than adding the FI-lab. The greatest improvement was achieved when both frailty indicators were used together. These findings suggest that electronic medical record-based frailty assessment methods can be useful tools for predicting long-term outcomes in older critically ill patients.


Subject(s)
Aftercare , Frailty , Humans , Aged , Critical Illness , Electronic Health Records , Frailty/diagnosis , Patient Discharge , Prognosis , Survivors
3.
Rev Sci Instrum ; 94(3): 035106, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-37012784

ABSTRACT

The compressed ultrafast photography (CUP) can capture non-repetitive time-evolving events at 7 × 1013 fps, which is anticipated to find a diverse range of applications in physics, biomedical imaging, and materials science. The feasibility of diagnosing ultrafast phenomenon of Z-pinch by using the CUP has been analyzed in this article. Specifically, a dual-channel CUP design has been adopted for acquiring high quality reconstructed images and the strategies of identical masks, uncorrelated masks, and complementary masks have been compared. Furthermore, the image of the first channel was rotated by 90° to balance the spatial resolution between the sweep direction and the non-sweep direction. Both five synthetic videos and two simulated Z-pinch videos were chosen as the ground truth to validate this approach. The average peak signal to noise ratio of the reconstruction results is 50.55 dB for the self-emission visible light video and 32.53 dB for the laser shadowgraph video with unrelated masks (rotated channel 1). The simulation results show that the time-space-evolving process of plasma distribution can be well retold, and the phenomenon of plasma instability can be accurately diagnosed by the dual-channel CUP with unrelated masks (rotated channel 1). This study may promote the practical applications of the CUP in the field of accelerator physics.

4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 51(3): 278-287, 2023 Mar 24.
Article in Chinese | MEDLINE | ID: mdl-36925138

ABSTRACT

Objective: Hyperlipidemia is closely related to premature acute myocardial infarction (AMI). The present study was performed to explore the correlation between various blood lipid components and the risk of premature AMI. Methods: This is a cross-sectional retrospective study. Consecutive patients with acute ST-segment elevation myocardial infarction (STEMI), who completed coronary angiography from October 1, 2020 to September 30, 2022 in our hospital, were enrolled and divided into premature AMI group (male<55 years old, female<65 years old) and late-onset AMI group. Total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), non-HDL-C, lipoprotein (a) (Lp (a)), apolipoprotein B (ApoB), apolipoprotein A-1 (ApoA-1), non-HDL-C/HDL-C and ApoB/ApoA-1 were analyzed. The correlation between the above blood lipid indexes and premature AMI was analyzed and compared by logistic regression, restricted cubic spline and receiver operating characteristic curve (ROC). Results: A total of 1 626 patients with STEMI were enrolled in this study, including 409 patients with premature AMI and 1 217 patients with late-onset AMI. Logistic regression analysis showed that the risk of premature AMI increased significantly with the increase of TG, non-HDL-C/HDL-C, non-HDL-C, ApoB/ApoA-1, TC and ApoB quintiles; while LDL-C, ApoA-1 and Lp (a) had no significant correlation with premature AMI. The restricted cubic spline graph showed that except Lp (a), LDL-C, ApoA-1 and ApoB/ApoA-1, other blood lipid indicators were significantly correlated with premature AMI. The ROC curve showed that TG and non-HDL-C/HDL-C had better predictive value for premature AMI. Inconsistency analysis found that the incidence and risk of premature AMI were the highest in patients with high TG and high non-HDL-C/HDL-C. Conclusion: TG, non-HDL-C/HDL-C and other blood lipid indexes are significantly increased in patients with premature AMI, among which TG is the parameter, most closely related to premature AMI, and future studies are needed to explore the impact of controlling TG on incidence of premature AMI.


Subject(s)
Myocardial Infarction , ST Elevation Myocardial Infarction , Humans , Male , Female , Middle Aged , Aged , Cross-Sectional Studies , Cholesterol, LDL , Retrospective Studies , Apolipoprotein A-I , Cholesterol , Apolipoproteins B , Triglycerides , Cholesterol, HDL , Lipids , Lipoproteins
5.
Rev Sci Instrum ; 93(3): 033702, 2022 Mar 01.
Article in English | MEDLINE | ID: mdl-35365019

ABSTRACT

A high-speed radiation imaging system based on an image converter of liquid scintillator filled capillary arrays has been developed, which is sensitive to x rays, gamma rays, and neutrons. This imaging system has advantages of both high spatial resolution and high sensitivity because increasing the thickness of the image converter only leads to little deterioration on imaging resolution. The capillary arrays have dimensions of 150 mm diameter and 50 mm thickness, with 100 µm diameter of each capillary. The fluorescence decay time of the filled liquid scintillator based on the mixture of p-xylene and 2,5-diphenyloxazole has been evaluated to be ∼3 ns with the single photon method under the gamma ray excitation. The spatial resolution has been experimentally evaluated to be about 1.15 and 0.6 mm, under excitation of x rays and neutrons, respectively. The imaging system has been applied for diagnosing the dynamic x-ray spot generated by the rod pinch. Two frames in single shot with 15 ns temporal resolution and 20 ns inter-frame separation time have been obtained, which show the spatiotemporal distribution of the electrons bombarding the tungsten rod, indicating the ability of this imaging system in diagnosing dynamic radiation objects. In addition, the technique of capillary arrays provides a promising path for applications of advanced liquid scintillators in the field of radiation imaging.

7.
Cancer Radiother ; 25(5): 441-446, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33958272

ABSTRACT

PURPOSE: The aim of this study was to evaluate the efficacy of liposome-paclitaxel and carboplatin combination chemoradiotherapy for patients with locally advanced esophageal squamous cell carcinoma (ESCC). PATIENTS AND METHODS: Seventy-nine consecutive patients treated with liposome-paclitaxel based concurrent chemoradiotherapy between January 2015 and December 2019 at Cancer hospital of the University of Chinese Academy of Sciences (Zhejiang cancer hospital) were enrolled in this study. The overall response, toxicities, progression-free survival and overall survival were analyzed with SPSS software. RESULTS: A total of 302 cycles of weekly chemotherapy were delivered, with a median 4 courses. After concurrent chemoradiotherapy (CCRT), the efficacy was classified as CR in 4 cases (5.1%), PR in 22 cases (28.2%) and SD in 51 cases (65.4%). The median PFS and OS time were 18.2 months and 23.4 months. The 3-year PFS and OS rates were 45.1% and 43.6%, respectively. CONCLUSIONS: Liposome-paclitaxel and carboplatin concurrent with radiotherapy is a safe and effective modality for locally advanced ESCC. Further clinical investigation are warranted to evaluate the efficacy of this regimen.


Subject(s)
Carboplatin/administration & dosage , Chemoradiotherapy , Esophageal Neoplasms/mortality , Esophageal Neoplasms/therapy , Esophageal Squamous Cell Carcinoma/mortality , Esophageal Squamous Cell Carcinoma/therapy , Paclitaxel/administration & dosage , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Esophageal Neoplasms/pathology , Esophageal Squamous Cell Carcinoma/pathology , Female , Humans , Liposomes/administration & dosage , Male , Middle Aged , Progression-Free Survival , Radiotherapy, Intensity-Modulated
8.
Microbiologyopen ; 9(11): e1119, 2020 11.
Article in English | MEDLINE | ID: mdl-33034165

ABSTRACT

The gut microbiota plays multiple critical roles in maintaining the health of the host, especially in ruminants. However, our understanding of the establishment of gut microbiota from birth to adulthood is still limited. To address this, the bacterial ecology of the rumen, abomasum, duodenum, and rectum in Holstein cows ranging in age from 1 week to 5 years old was investigated using 16S rRNA gene sequencing in this study. A major change in the composition, diversity, and abundance of bacteria was observed with increased age (p < 0.05). Microbiota gradually matured in each gut segment and followed the Gompertz model when the Chao1, Shannon, and maturity indexes (p < 0.05, r > 0.94) were applied. Importantly, the Gompertz model parameter differed between the gut segments, with the highest microbiota growth rate found in the rectum, followed by the rumen, abomasum, and duodenum. Compared to older animals, greater microbiota similarities were found in the adjacent gut segments of younger animals (p < 0.05). Our findings indicate that gut microbiotas are established quickly when cows are young and then slow with age and that early in life, hindgut microbiota may be more easily affected by the foregut microbiota.


Subject(s)
Bacteria/classification , Bacteria/isolation & purification , Bacterial Load , Gastrointestinal Microbiome/physiology , Abomasum/microbiology , Animals , Bacteria/genetics , Bacteria/growth & development , Cattle , Duodenum/microbiology , Gastrointestinal Microbiome/genetics , RNA, Ribosomal, 16S/genetics , Rectum/microbiology , Rumen/microbiology
9.
Zhonghua Gan Zang Bing Za Zhi ; 28(4): 351-356, 2020 Apr 20.
Article in Chinese | MEDLINE | ID: mdl-32403889

ABSTRACT

Objective: To summarize the clinical diagnosis and therapeutic method in chronic hepatitis B (CHB) combined with autoimmune hepatitis (AIH). Methods: Clinical manifestations, laboratory examination, imaging, histopathological characteristics, treatment and prognosis of 19 cases diagnosed with CHB combined with AIH followed at the outpatient Department of Gastroenterology of Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine during December 2013 to June 2018 were retrospectively analyzed. Paired sample t-test was used before and after treatment for the measurement of normal distribution data. Measurement data of non-normal distribution were expressed as a median (quartile spacing) and Wilcoxon matched-pairs signed rank test was used before and after treatment. Results: Among the 19 cases, 5 were male and 14 were female. The age of onset was 35 to 63 years, and the average age was 47.10 ± 8.76 years. There were 12 cases diagnosed with CHB before AIH, 5 cases diagnosed with AIH before CHB, and 2 cases diagnosed with AIH and CHB at the same time. After the definite diagnosis of CHB combined with AIH, nucleoside (acid) analogues (antiviral against hepatitis B virus) combined glucocorticoid therapy were given, and azathioprine or mycophenolate mofetil (immunosuppressant) was added according to the intrahepatic inflammation (inflammation graded at G3 and above) and leukocyte conditions. The duration of treatment varied between 2 weeks to 16 (median treatment duration of 6 weeks), except for one case who was just diagnosed and followed up. Biochemical indicators and immunoglobulin of the remaining 18 cases before and after treatment was significantly decreased, and the differences were statistically significant (P < 0.05), with HBV DNA < 20 copies/ml. Conclusion: CHB combined with AIH diagnosis can be easily missed. Therefore, it requires comprehensive diagnosis combined with clinical characteristics, autoantibodies, and immunoglobulin levels with special emphasis on pathological characteristics of liver tissue. Anti-HBc-positive patients using immunosuppressant should be carefully monitored for HBV DNA and anti-HBV treatment should be given if necessary.


Subject(s)
Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/therapy , Hepatitis, Autoimmune/diagnosis , Hepatitis, Autoimmune/therapy , Adult , China , Female , Hepatitis B virus , Hepatitis B, Chronic/complications , Hepatitis, Autoimmune/complications , Humans , Male , Middle Aged , Retrospective Studies
11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 54(5): 555-562, 2020 May 06.
Article in Chinese | MEDLINE | ID: mdl-32388958

ABSTRACT

Objective: To systematically review research on the association between vitamin K and type 2 diabetes and diabetes-related biomarkers in humans, and evaluate the role of vitamin K in the prevention of type 2 diabetes. Methods: "Vitamin K", "type 2 diabetes" and related terms were searched in PubMed, EMBASE, China National Knowledge Infrastructure (CNKI) and Wanfang Med Online up to November 2018. Results: A total of 1 Chinese and 12 English articles were included. Among 6 observational studies, 5 of them showed that higher dietary vitamin K intake and plasma vitamin K level were associated with the decrease of the risk of type 2 diabetes. Among 6 clinical intervention studies, 5 of them indicated that the supplementation of vitamin K(1) or K2 could have positive influence on insulin metabolism. One Mendelian randomization study showed higher circulation vitamin K level might reduce the risk of type 2 diabetes. Conclusion: Vitamin K plays an important role in the prevention and control of type 2 diabetes, which may be related to the improvement of insulin metabolism and blood glucose level.


Subject(s)
Diabetes Mellitus, Type 2/blood , Vitamin K/blood , Blood Glucose , China , Dietary Supplements , Humans , Insulin/metabolism , Observational Studies as Topic , Vitamin K/therapeutic use
12.
Cryo Letters ; 41(3): 140-144, 2020.
Article in English | MEDLINE | ID: mdl-33988643

ABSTRACT

BACKGROUND: Noninvasive monitoring of cryosurgery is important for performing precise monitoring of the freezing process in situ and evaluating postoperative effects after therapy. One potential approach is to monitor the normal and freeze-thawed tissues through ultrasonic backscattered signal processing. OBJECTIVE: A noninvasive method for cryosurgery monitoring based on the analysis of microstructural characteristics of in vitro porcine liver tissues at different state including normal and freeze-thawed tissues by estimating the center frequency of scatterers (CFS) using the autoregressive (AR) cepstrum of ultrasonic backscattered signals. MATERIALS AND METHODS: The method is based on the discrete scattering model described in the tissue characterization literature and the observation that most biological tissues are semi-regular scattering lattices. A total of ten in vitro porcine liver samples were used and freeze by water bath in the experiments. RESULTS: Experimental results show that the CFS in porcine liver tissues decreases after pre-frozen and then thawed. CONCLUSION: The CFS obtained using this method may be used as a characteristic parameter for tissue characterization in noninvasive monitoring the transition zone between frozen and unfrozen tissues during the surgical therapy, and evaluating postoperative effects.


Subject(s)
Cryopreservation , Cryosurgery , Liver , Ultrasonography , Animals , Freezing , Liver/diagnostic imaging , Liver/surgery , Swine
13.
Epidemiol Infect ; 149: e8, 2020 12 28.
Article in English | MEDLINE | ID: mdl-33436107

ABSTRACT

Previous studies have revealed associations of meteorological factors with tuberculosis (TB) cases. However, few studies have examined their lag effects on TB cases. This study was aimed to analyse nonlinear lag effects of meteorological factors on the number of TB notifications in Hong Kong. Using a 22-year consecutive surveillance data in Hong Kong, we examined the association of monthly average temperature and relative humidity with temporal dynamics of the monthly number of TB notifications using a distributed lag nonlinear models combined with a Poisson regression. The relative risks (RRs) of TB notifications were >1.15 as monthly average temperatures were between 16.3 and 17.3 °C at lagged 13-15 months, reaching the peak risk of 1.18 (95% confidence interval (CI) 1.02-1.35) when it was 16.8 °C at lagged 14 months. The RRs of TB notifications were >1.05 as relative humidities of 60.0-63.6% at lagged 9-11 months expanded to 68.0-71.0% at lagged 12-17 months, reaching the highest risk of 1.06 (95% CI 1.01-1.11) when it was 69.0% at lagged 13 months. The nonlinear and delayed effects of average temperature and relative humidity on TB epidemic were identified, which may provide a practical reference for improving the TB warning system.


Subject(s)
Humidity , Temperature , Tuberculosis/diagnosis , Tuberculosis/epidemiology , Air Pollution , Hong Kong/epidemiology , Humans , Seasons , Time Factors
14.
Phys Rev Lett ; 123(20): 206601, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31809106

ABSTRACT

Recently discovered Dirac semimetals (DSMs) with two Dirac nodes, such as Na_{3}Bi and Cd_{2}As_{3}, are regarded as carrying the Z_{2} topological charge in addition to the chiral charge. We study the Floquet phase transition of Z_{2} topological DSMs subjected to a beam of circularly polarized light. Owing to the resulting interplay of the chiral and Z_{2} charges, the Weyl nodes are not only chirality dependent but also spin dependent, which constrains the behavior in creation and annihilation of the pair of Weyl nodes. Interestingly, we find a novel phase: One spin band is in the Weyl semimetal phase while the other is in the insulator phase, and we dub it the Weyl half-metal (WHM) phase. We further study the spin-dependent transport in a Dirac-Weyl semimetal junction and find a spin filter effect as a fingerprint of the existence of the WHM phase. The proposed spin filter effect, based on the WHM bulk band, is highly tunable in a broad parameter regime and robust against magnetic disorder, which is expected to overcome the shortcomings of the previously proposed spin filter based on the topological edge or surface states. Our results offer a unique opportunity to explore the potential applications of topological DSMs in spintronics.

15.
Zhonghua Fu Chan Ke Za Zhi ; 54(10): 654-659, 2019 Oct 25.
Article in Chinese | MEDLINE | ID: mdl-31648440

ABSTRACT

Objective: To explore the relationship between hemoglobin (Hb) level during the first trimester of pregnancy and gestational diabetes mellitus (GDM). Methods: A total of 1 276 participants, who underwent scheduled prenatal examination and normal singleton delivery at the Fifth People's Hospital of Shanghai and Hospital of Intergrated Chinese and Western Medicine in Minhang District, from January 2016 to May 2018 were included. There were 99 cases of GDM (GDM group) and 1 177 cases of normal (control group) pregnant women.Based on the serum Hb level during the first trimester of pregnancy, participants were divided into three groups, 236 cases of low Hb level group (Hb<110 g/L), 868 cases of normal Hb level group (110 g/L≤Hb<130 g/L), and 172 cases of high Hb level group (Hb≥130 g/L). Maternal clinical data were collected, including Hb level during the first trimester of pregnancy, three-point blood glucose (BG) of oral glucose tolerance test (OGTT) and fasting insulin during the second trimester of pregnancy. Homeostasis model assessment of insulin resistance index (HOMA-IR) and homeostasis model assessment of pancreatic ß cell function index (HOMA-ß) were used to evaluate insulin resistance and pancreatic ß cell function. Results: (1) Hb level during the first trimester of pregnancy in GDM group was significantly higher than that in control group [(123±10),(119±11) g/L, P<0.05]. There were no significant difference in gravidity, parity, index of liver and renal function (all P>0.05). (2) Pre-pregnancy body mass index (BMI), 1-hour BG and 2-hour BG of OGTT were significantly increased in the high Hb level group during the first trimester of pregnancy, which were (23±4) kg/m(2), (7.3±2.0) mmol/L, and (6.5±1.4) mmol/L (P<0.05), respectively. The pre-pregnancy BMI, 1-hour BG and 2-hour BG of the normal or low Hb level group were (22±3) kg/m(2), (6.7±1.6) mmol/L, (6.1±1.2) mmol/L; (22±3) kg/m(2), (6.5±1.5) mmol/L, (5.9±1.1) mmol/L, respectively. There were no statistically significant difference in levels of fasting blood glucose, fasting insulin, HOMA-IR and HOMA-ß within 3 groups (all P>0.05). (3) In the high Hb level group, prevalence of pregnancy overweight or obesity and GDM were the highest, which were 37.2%(64/172) and 15.1%(26/172), respectively; the differences were statistically significant (all P<0.05). (4) The serum Hb level in the first trimester was positively related with pre-pregnancy BMI (r=0.130, P<0.05), 1-hour BG (r=0.129, P<0.05), 2-hour BG (r=0.134, P<0.05), fasting insulin (r=0.096, P<0.05), and HOMA-IR (r=0.101, P<0.05).Logistic regression indicated that Hb≥130 g/L during the first trimester of pregnancy was an independent risk factor for GDM (OR=2.799, 95%CI: 1.186-6.604; P<0.05). Conclusion: The high level of Hb (Hb≥130 g/L) during the first trimester of pregnancy is associated with GDM.


Subject(s)
Blood Glucose/analysis , Diabetes, Gestational/diagnosis , Glucose Intolerance/diagnosis , Glucose Tolerance Test , Hemoglobins/analysis , Insulin Resistance , Pregnancy Trimester, First/blood , Adult , Asian People , Blood Glucose/metabolism , Body Mass Index , China/epidemiology , Diabetes, Gestational/blood , Diabetes, Gestational/epidemiology , Female , Humans , Incidence , Pregnancy , Risk Factors
16.
Sci Rep ; 9(1): 7681, 2019 05 22.
Article in English | MEDLINE | ID: mdl-31118458

ABSTRACT

This 4-year randomized controlled trial (RCT) aimed at investigating whether routine home use of both a SnCl2/AmF/NaF-containing mouth rinse and toothpaste has a preventive effect on oral health. Fifty-four test subjects were examined in biannual intervals. The primary endpoint "dental erosion" was determined by the Basic Erosive Wear Examination (BEWE). The secondary endpoints were "saliva pH", "dentin hypersensitivity" generated by Visual Analogue Scale (VAS), and "discoloration" measured by the Lobene Stain Index (LSI). A mixed model for repeated measures (MMRM) was used to analyze the primary endpoint "dental erosion". Primary analysis showed a significant intervention effect of the SnCl2/AmF/NaF-containing test product (p1 = 0.0242). This result was confirmed by two additional MMRM-based sensitivity analyses. Comparison of all models showed "dental erosion" values of the intervention group  below values of the control group. Discoloration of the teeth was significantly higher in the intervention than in the control group at all time points. Saliva pH and dentin hypersensitivity were not significantly different between groups over four years. In summary, this RCT is the first to indicate a possible preventive effect of SnCl2/AmF/NaF-containing oral hygiene products on dental erosion over a follow-up period of four years.


Subject(s)
Amines/therapeutic use , Dentifrices/administration & dosage , Dentin Sensitivity/prevention & control , Mouthwashes/administration & dosage , Tin Fluorides/therapeutic use , Tooth Erosion/prevention & control , Adult , Amines/administration & dosage , Female , Fluoridation , Follow-Up Studies , Humans , Hydrogen-Ion Concentration , Male , Pilot Projects , Saliva/chemistry , Tin Fluorides/administration & dosage , Tooth Bleaching , Visual Analog Scale , Young Adult
17.
Cryo Letters ; 40(1): 58-63, 2019.
Article in English | MEDLINE | ID: mdl-30955032

ABSTRACT

BACKGROUND: Ultrasound guidance of cryotherapy could be improved if changes of tissue characterization parameters during freezing could be used to monitor freezing profiles and estimate frostbite distributions. OBJECTIVE: To investigate if B-mode ultrasonic imaging can provide sufficient information to define the damaged zone during cryotherapy by quantifying the differences of texture features between fresh and frozen-thawed porcine liver tissue. MATERIALS AND METHODS: The B-mode ultrasonic images were obtained from ten porcine liver tissue samples before and after frozen-thawing treatment, then 20 texture parameters of the grey level histogram (GLH) and the grey level co-occurrence matrix (GLCM) from each image were extracted and analyzed statistically. RESULTS: It was found that the differences in two texture parameters between the fresh and frozen-thawed tissue are significant enough for diagnostic purpose (variance: 317.0%, contrast: 144.4%). CONCLUSION: Texture feature analysis of B-mode ultrasonic images can effectively differentiate the fresh and frozen-thawed porcine liver tissues, which offers a prospect for the future practice of evaluating the effectiveness of cryotherapy using Ultrasound.


Subject(s)
Cryotherapy , Freezing , Liver/diagnostic imaging , Ultrasonography , Animals , Swine
18.
Phys Rev Lett ; 122(3): 036601, 2019 Jan 25.
Article in English | MEDLINE | ID: mdl-30735409

ABSTRACT

Weyl semimetals (WSMs) host charged Weyl fermions as emergent quasiparticles. We develop a unified analytical theory for the anomalous positive longitudinal magnetoconductivity (LMC) in a WSM, which bridges the gap between the classical and ultraquantum approaches. More interestingly, the LMC is found to exhibit periodic-in-1/B quantum oscillations, originating from the oscillations of the nonequilibrium chiral chemical potential. The quantum oscillations, superposed on the positive LMC, are a remarkable fingerprint of a WSM phase with a chiral anomaly, whose observation is a valid criteria for identifying a WSM material. In fact, such quantum oscillations were already observed by several experiments.

19.
J Phys Condens Matter ; 31(12): 125502, 2019 Mar 27.
Article in English | MEDLINE | ID: mdl-30630133

ABSTRACT

We investigate the topological pumping effect in Weyl semimetals, subject to the modulation of two ac electric fields along y  and z directions, respectively. We show that the pumping effect originates from the anomalous velocity related to the Berry curvature. The direction of the pumping current is dependent on the chirality of the Weyl fermions. While the total particle current is vanishing because the Weyl points of opposite chirality always come in pairs in Weyl semimetals, the pump gives rise to a net chirality current or valley current. The noiseless valley current generated can be useful in valleytronic applications.

20.
J Mater Chem B ; 7(4): 630-639, 2019 01 28.
Article in English | MEDLINE | ID: mdl-32254796

ABSTRACT

The aim of this study was to investigate the influence of poly(lactide-co-glycolide) (PLGA) and polydopamine (PDA) as coating materials on the tensile strength, surface performance, in vitro cell behavior and the in vivo material-tissue reaction of bacterial cellulose (BC) membranes. The coated membranes were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and scanning electron microscopy (SEM), demonstrating that the PDA forms the dispersion phase and penetrates into the BC substrates while PLGA only adheres to the BC surface. Mechanical tests and fractured surface morphology reveal that penetration of PDA into BC membranes enhances the mechanical strength by strongly bonding the nanofibers. The PLGA coated BC membrane obtained by adhesion debonds from the BC substrate under stress, leading to a decrease in the mechanical strength of the membrane. The in vitro cell culture experiments were established to assess cell attachment and spreading by SEM and DAPI (4',6-diamidino-2-phenylindole) staining and expression of collagen I, which showed a better performance on the PDA-BC than on the PLGA-BC and bare BC membranes. However, the in vivo results of the rabbit back implantation indicated that BC membrane surface modification by PDA is not effective for cell proliferation and collagen accumulation when compared to bare and PLGA coated BC, whereas PLGC-BC were surrounded by a thicker layer of connective tissues with slight neovascularization demonstrating superior tissue integration. PDA based materials still have a long way to go before clinical applications. However, PLGA coating has excellent biocompatibility in clinical as well as in experimental use.


Subject(s)
Coated Materials, Biocompatible , Indoles , Polyglactin 910 , Polymers , Animals , Cell Adhesion/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Indoles/chemistry , Indoles/pharmacology , Male , Polyglactin 910/chemistry , Polyglactin 910/pharmacology , Polymers/chemistry , Polymers/pharmacology , Rabbits , Surface Properties
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