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1.
Nano Lett ; 24(30): 9163-9168, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39037721

ABSTRACT

Magneto-optical (MO) polymer nanocomposites have emerged as alternatives to conventional MO crystals, particularly in nanophotonics applications, thanks to their better processing flexibility and superior Verdet constants. However, a higher Verdet constant commonly comes with excessive optical loss due to increased absorption and scattering, resulting in a constant or reduced figure-of-merit (FOM) defined as the Verdet constant over optical loss. By doping magnetite (Fe3O4) nanoparticles with Tb3+ ions, we report a new strategy to enhance the Verdet constant without increasing the optical loss. The Fe3O4:Tb3+ nanocomposite is one of a kind that simultaneously achieves a state-of-the-art Verdet constant of 5.6 × 105 °/T·m and a state-of-the-art FOM of 31°/T in the near-infrared region.

2.
Rev Cardiovasc Med ; 25(6): 205, 2024 Jun.
Article in English | MEDLINE | ID: mdl-39076317

ABSTRACT

Background: Catheter ablation (CA) is an effective therapy for atrial fibrillation (AF) and, although radiofrequency ablation (RFA) is the standard treatment for pulmonary vein isolation (PVI), it is complex and time-consuming. Laser balloon ablation (LBA) has been introduced to simplify the conventional RFA; however, results of studies comparing LBA and RFA remain controversial. As such, this investigation aimed to comprehensively evaluate the efficacy and safety of LBA versus RFA. Methods: The PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases were searched for relevant studies. The primary endpoints were the freedom from atrial tachyarrhythmia (ATA) and procedure-related complications. Results: Twelve studies including 1274 subjects were included. LBA and RFA yielded similar rates of freedom from ATA (72.5% vs. 68.7%, odds ratio [OR] = 1.26, 95% confidence interval [CI] 1.0-1.7, p = 0.11) and procedure-related complications (7.7% vs. 6.5%, OR = 1.17, 95% CI 0.72-1.90, p = 0.536). LBA with the second- and third-generation laser balloons (LB2/3) yielded remarkably higher rates of freedom from ATA than RFA using contact-force technology (RFA-CF) (OR = 1.91, p = 0.013). Significantly lower pulmonary vein (PV) reconnection rates (OR = 0.51, p = 0.021), but higher phrenic nerve palsy (PNP) rates (OR = 3.42, p = 0.023) were observed in the LBA group. LBA had comparable procedure (weighted mean difference [WMD] = 8.43 min, p = 0.337) and fluoroscopy times (WMD = 3.09 min, p = 0.174), but a longer ablation time (WMD = 12.57 min, p = 0.00) than those for RFA. Conclusions: LBA and RFA treatments were comparable in terms of freedom from ATA and postprocedural complications in patients with AF. Compared with RFA, LBA was associated with significantly lower PV reconnection rates, but a higher incidence of PNP and longer ablation time.

3.
Opt Lett ; 49(9): 2449-2452, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38691741

ABSTRACT

Broadband frequency comb generation through cascaded quadratic nonlinearity remains experimentally untapped in free-space cavities with bulk χ(2) materials mainly due to the high threshold power and restricted ability of dispersion engineering. Thin-film lithium niobate (LN) is a good platform for nonlinear optics due to the tight mode confinement in a nano-dimensional waveguide, the ease of dispersion engineering, large quadratic nonlinearities, and flexible phase matching via periodic poling. Here we demonstrate broadband frequency comb generation through dispersion engineering in a thin-film LN microresonator. Bandwidths of 150 nm (80 nm) and 25 nm (12 nm) for center wavelengths at 1560 and 780 nm are achieved, respectively, in a cavity-enhanced second-harmonic generation (doubly resonant optical parametric oscillator). Our demonstration paves the way for pure quadratic soliton generation, which is a great complement to dissipative Kerr soliton frequency combs for extended interesting nonlinear applications.

4.
Respir Res ; 25(1): 199, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38720331

ABSTRACT

BACKGROUND: Bronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) remains a devastating clinical complication seriously affecting the therapeutic outcome of preterm infants. Hence, early prevention and timely diagnosis prior to pathological change is the key to reducing morbidity and improving prognosis. Our primary objective is to utilize machine learning techniques to build predictive models that could accurately identify BPD infants at risk of developing PH. METHODS: The data utilized in this study were collected from neonatology departments of four tertiary-level hospitals in China. To address the issue of imbalanced data, oversampling algorithms synthetic minority over-sampling technique (SMOTE) was applied to improve the model. RESULTS: Seven hundred sixty one clinical records were collected in our study. Following data pre-processing and feature selection, 5 of the 46 features were used to build models, including duration of invasive respiratory support (day), the severity of BPD, ventilator-associated pneumonia, pulmonary hemorrhage, and early-onset PH. Four machine learning models were applied to predictive learning, and after comprehensive selection a model was ultimately selected. The model achieved 93.8% sensitivity, 85.0% accuracy, and 0.933 AUC. A score of the logistic regression formula greater than 0 was identified as a warning sign of BPD-PH. CONCLUSIONS: We comprehensively compared different machine learning models and ultimately obtained a good prognosis model which was sufficient to support pediatric clinicians to make early diagnosis and formulate a better treatment plan for pediatric patients with BPD-PH.


Subject(s)
Bronchopulmonary Dysplasia , Hypertension, Pulmonary , Machine Learning , Humans , Bronchopulmonary Dysplasia/diagnosis , Infant, Newborn , Hypertension, Pulmonary/diagnosis , Male , Female , Retrospective Studies , Infant, Extremely Premature , Infant, Premature
5.
BMC Gastroenterol ; 24(1): 99, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38443794

ABSTRACT

In this study, we implemented a combination of data augmentation and artificial intelligence (AI) model-Convolutional Neural Network (CNN)-to help physicians classify colonic polyps into traditional adenoma (TA), sessile serrated adenoma (SSA), and hyperplastic polyp (HP). We collected ordinary endoscopy images under both white and NBI lights. Under white light, we collected 257 images of HP, 423 images of SSA, and 60 images of TA. Under NBI light, were collected 238 images of HP, 284 images of SSA, and 71 images of TA. We implemented the CNN-based artificial intelligence model, Inception V4, to build a classification model for the types of colon polyps. Our final AI classification model with data augmentation process is constructed only with white light images. Our classification prediction accuracy of colon polyp type is 94%, and the discriminability of the model (area under the curve) was 98%. Thus, we can conclude that our model can help physicians distinguish between TA, SSA, and HPs and correctly identify precancerous lesions such as TA and SSA.


Subject(s)
Adenoma , Polyps , Humans , Artificial Intelligence , Endoscopy , Neural Networks, Computer , Adenoma/diagnostic imaging
6.
Nature ; 558(7710): 410-414, 2018 06.
Article in English | MEDLINE | ID: mdl-29892031

ABSTRACT

Optical frequency combs, which emit pulses of light at discrete, equally spaced frequencies, are cornerstones of modern-day frequency metrology, precision spectroscopy, astronomical observations, ultrafast optics and quantum information1-7. Chip-scale frequency combs, based on the Kerr and Raman nonlinearities in monolithic microresonators with ultrahigh quality factors8-10, have recently led to progress in optical clockwork and observations of temporal cavity solitons11-14. But the chromatic dispersion within a laser cavity, which determines the comb formation15,16, is usually difficult to tune with an electric field, whether in microcavities or fibre cavities. Such electrically dynamic control could bridge optical frequency combs and optoelectronics, enabling diverse comb outputs in one resonator with fast and convenient tunability. Arising from its exceptional Fermi-Dirac tunability and ultrafast carrier mobility17-19, graphene has a complex optical dispersion determined by its optical conductivity, which can be tuned through a gate voltage20,21. This has brought about optoelectronic advances such as modulators22,23, photodetectors 24 and controllable plasmonics25,26. Here we demonstrate the gated intracavity tunability of graphene-based optical frequency combs, by coupling the gate-tunable optical conductivity to a silicon nitride photonic microresonator, thus modulating its second- and higher-order chromatic dispersions by altering the Fermi level. Preserving cavity quality factors up to 106 in the graphene-based comb, we implement a dual-layer ion-gel-gated transistor to tune the Fermi level of graphene across the range 0.45-0.65 electronvolts, under single-volt-level control. We use this to produce charge-tunable primary comb lines from 2.3 terahertz to 7.2 terahertz, coherent Kerr frequency combs, controllable Cherenkov radiation and controllable soliton states, all in a single microcavity. We further demonstrate voltage-tunable transitions from periodic soliton crystals to crystals with defects, mapped by our ultrafast second-harmonic optical autocorrelation. This heterogeneous graphene microcavity, which combines single-atomic-layer nanoscience and ultrafast optoelectronics, will help to improve our understanding of dynamical frequency combs and ultrafast optics.

7.
J Shoulder Elbow Surg ; 32(6): 1314-1322, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36871608

ABSTRACT

HYPOTHESIS: Adhesive capsulitis (AC) is a common clinical condition of the shoulders without a clear pathophysiology or etiology. Although thyroid disease has been linked to AC, an appropriate understanding of the disease and its epidemiological evidence are lacking. This metaanalysis investigated the association of AC with thyroid disease and identified which manifestations of thyroid disease contribute to the risk of AC. MATERIALS AND METHODS: The databases of PubMed, Embase, and Scopus were searched for literature retrieval up to September 20, 2022. Articles evaluating the association between AC and any type of thyroid disease were enrolled. Data from studies reporting the prevalence and its 95% confidence interval (CI) were pooled. Subgroup analysis was performed on the different manifestations of thyroid disease. We explored heterogeneity with sensitivity analyses and publication bias with funnel plots and Egger's tests. A trim and fill analysis was conducted if publication bias was found. RESULTS: Results: In total, 10 case-control studies comprising a total of 127,967 patients were included. The prevalence of thyroid disease was significantly higher in patients with AC (odds ratio [OR] = 1.87, 95% CI: 1.37-2.57, P < .0001) than in patients without AC. The results of subgroup analysis indicated significantly higher rates of hypothyroidism (OR = 1.92, 95% CI: 1.09-3.39, P = .02) and subclinical hypothyroidism (OR = 2.56, 95% CI: 1.81-3.63, P < .00001), but not hyperthyroidism (OR = 1.42, 95% CI: 0.63-3.22, P = .40), among patients with AC than among those without AC. CONCLUSIONS: Our meta-analysis demonstrated that thyroid disease, especially when presenting as hypothyroidism or subclinical hypothyroidism, is associated with an increased risk of AC. Evidence for an association between hyperthyroidism and AC was not found, although this may be due to the lack of related studies. Further research on the pathogeneses of and relationship between these two diseases is warranted.


Subject(s)
Bursitis , Hyperthyroidism , Hypothyroidism , Humans , Case-Control Studies , Hyperthyroidism/complications , Hyperthyroidism/epidemiology , Hypothyroidism/complications , Hypothyroidism/epidemiology , Prevalence , Thyroid Diseases/complications , Thyroid Diseases/epidemiology
8.
Medicina (Kaunas) ; 59(6)2023 Jun 20.
Article in English | MEDLINE | ID: mdl-37374383

ABSTRACT

Background and Objectives: Osteoporosis is characterized by low bone mass and high bone fragility. Findings regarding the association of coffee and tea intake with osteoporosis have been inconsistent. We conducted this meta-analysis to investigate whether coffee and tea intake is associated with low bone mineral density (BMD) and high hip fracture risk. Materials and Methods: PubMed, MEDLINE, and Embase were searched for relevant studies published before 2022. Studies on the effects of coffee/tea intake on hip fracture/BMD were included in our meta-analysis, whereas those focusing on specific disease groups and those with no relevant coffee/tea intake data were excluded. We assessed mean difference (MD; for BMD) and pooled hazard ratio (HR; for hip fracture) values with 95% confidence interval (CI) values. The cohort was divided into high- and low-intake groups considering the thresholds of 1 and 2 cups/day for tea and coffee, respectively. Results: Our meta-analysis included 20 studies comprising 508,312 individuals. The pooled MD was 0.020 for coffee (95% CI, -0.003 to 0.044) and 0.039 for tea (95% CI, -0.012 to 0.09), whereas the pooled HR was 1.008 for coffee (95% CI, 0.760 to 1.337) and 0.93 for tea (95% CI, 0.84 to 1.03). Conclusions: Our meta-analysis results suggest that daily coffee or tea consumption is not associated with BMD or hip fracture risk.


Subject(s)
Hip Fractures , Osteoporosis , Humans , Bone Density , Coffee/adverse effects , Tea/adverse effects , Risk Factors
9.
Opt Lett ; 47(1): 122-125, 2022 Jan 01.
Article in English | MEDLINE | ID: mdl-34951897

ABSTRACT

Kerr microcombs hold the promise of bringing frequency combs onto the chip and into a variety of applications requiring low size, weight, power, and cost. However, reliable Kerr microcomb generation is hindered by the thermal effect and multistability of dissipative Kerr solitons (DKSs). Past approaches toward Kerr microcomb reliability include either deterministic single-soliton generation or self-starting soliton behavior but not both. Here we describe a regime of DKSs that is both deterministic and self-starting, in which only a single soliton can stably exist. We term this new DKS regime "monostable DKSs" (MS-DKSs) as all other optical behaviors, such as continuous-wave-only and multiple solitons, are fundamentally forbidden by the design. We establish a graphical model to describe MS-DKSs and discuss the design principles of MS-DKSs. We numerically demonstrate the MS-DKS behavior in an example periodically poled lithium niobate microring resonator.

10.
Medicina (Kaunas) ; 58(4)2022 Mar 30.
Article in English | MEDLINE | ID: mdl-35454336

ABSTRACT

Background and Objectives: Osteoporosis and anemia are prevalent among chronic kidney disease stage 5D (CKD stage 5D) patients. Osteoblasts are known as the niche cells of hematopoietic stem cells (HSCs) and stimulate HSCs to form blood-cell lineages within bone marrow microenvironments. We hypothesized that an inverse correlation may exist between mean corpuscular volume (MCV), a surrogate for ineffective hematopoiesis, and bone mineral density (BMD) in the CKD stage 5D population. Materials and Methods: This is a cross-sectional designed cohort study evaluating CKD stage 5D patients who have received dialysis therapy for over three months. Baseline clinical characteristics and laboratory data were prospectively collected. The dual-energy X-ray absorptiometry (DXA) method was used to measure BMD at five sites, which were bilateral femoral neck, total hip, and lumbar spine 1-4. The Pearson correlation test was initially adopted, and a multivariate linear regression model was further applied for potential confounder adjustments. Results: From September 2020 to January 2021, a total of 123 CKD stage 5D patients were enrolled. The Pearson correlation test revealed a significant inverse association between MCV and BMD at bilateral femoral neck and lumbar spine. The lowest T-score of the five body sites was determined as the recorded T-score. After adjustments for several potential confounding factors, the multivariate linear regression model found consistent negative associations between T-score and MCV. Conclusions: The present study found significant inverse correlations between MCV and BMD at specific body locations in patients on dialysis. A decreased T-score was also found to be associated with macrocytosis after adjustments for confounding variables. However, direct evidence for the causative etiology was lacking.


Subject(s)
Kidney Failure, Chronic , Renal Insufficiency, Chronic , Absorptiometry, Photon/methods , Bone Density , Cohort Studies , Cross-Sectional Studies , Erythrocyte Indices , Female , Humans , Kidney Failure, Chronic/complications , Lumbar Vertebrae , Male , Renal Dialysis/adverse effects , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/therapy
11.
Medicina (Kaunas) ; 58(7)2022 Jun 30.
Article in English | MEDLINE | ID: mdl-35888594

ABSTRACT

Background and Objectives: The study assessed the effectiveness of a fracture liaison service (FLS) after 1 year of implementation in improving the outcomes of hip fracture surgery in older adult patients at Taipei Municipal Wanfang Hospital. Materials and Methods: The Wanfang hospital's FLS program was implemented using a multipronged programmatic strategy. The aims were to encourage the screening and treatment of osteoporosis and sarcopenia, to take a stratified care approach for patients with a high risk of poor postoperative outcomes, and to offer home visits for the assessment of environmental hazards of falling, and to improve the patient's adherence to osteoporosis treatment. The clinical data of 117 and 110 patients before and after FLS commencement, respectively, were collected from a local hip fracture registry; the data were analyzed to determine the outcomes 1 year after hip fracture surgery in terms of refracture, mortality, and activities of daily living. Results: The implementation of our FLS significantly increased the osteoporosis treatment rate after hip fracture surgery from 22.8% to 72.3%, significantly decreased the 1-year refracture rate from 11.8% to 4.9%, non-significantly decreased 1-year mortality from 17.9% to 11.8%, and improved functional outcomes 1 year after hip fracture surgery. Conclusions: Implementation of our FLS using the multipronged programmatic strategy effectively improved the outcomes and care quality after hip fracture surgery in the older adult population, offering a successful example as a valuable reference for establishing FLS to improve the outcomes in vulnerable older adults.


Subject(s)
Bone Density Conservation Agents , Hip Fractures , Osteoporosis , Osteoporotic Fractures , Activities of Daily Living , Aged , Bone Density Conservation Agents/therapeutic use , Hip Fractures/epidemiology , Hip Fractures/surgery , Hospitals, Municipal , Humans , Osteoporosis/drug therapy , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/prevention & control , Osteoporotic Fractures/surgery , Secondary Prevention
12.
J Antimicrob Chemother ; 76(2): 451-459, 2021 01 19.
Article in English | MEDLINE | ID: mdl-33057603

ABSTRACT

BACKGROUND: According to our preliminary study, BLI-489 has the potential to inhibit the hydrolysing activity of OXA-51-like ß-lactamase produced by carbapenem-resistant Acinetobacter baumannii (CRAb). OBJECTIVES: In the present study, the in vitro and in vivo activities of imipenem combined with BLI-489 against CRAb producing carbapenem-hydrolysing class D ß-lactamases (CHDLs), namely OXA-23, OXA-24, OXA-51 and OXA-58, were determined. METHODS: A chequerboard analysis of imipenem and BLI-489 was performed using 57 and 7 clinical CRAb isolates producing different CHDLs and MBLs, respectively. Four representative strains harbouring different CHDL genes were subjected to a time-kill assay to evaluate the synergistic effects. An in silico docking analysis was conducted to simulate the interactions between BLI-489 and the different families of CHDLs. The in vivo activities of this combination were assessed using a Caenorhabditis elegans survival assay and a mouse pneumonia model. RESULTS: Chequerboard analysis showed that imipenem and BLI-489 had a synergistic effect on 14.3, 92.9, 100, 16.7 and 100% of MBL-, OXA-23-, OXA-24-like-, OXA-51-like- and OXA-58-producing CRAb isolates, respectively. In the time-kill assay, imipenem and BLI-489 showed synergy against OXA-24-like-, OXA-51-like- and OXA-58-, but not OXA-23-producing CRAb isolates after 24 h. The in silico docking analysis showed that BLI-489 could bind to the active sites of OXA-24 and OXA-58 to confer strong inhibition activity. The combination of imipenem and BLI-489 exhibited synergistic effects for the rescue of CRAb-infected C. elegans and mice. CONCLUSIONS: Imipenem combined with BLI-489 has synergistic effects against CHDL-producing CRAb isolates.


Subject(s)
Acinetobacter baumannii , Animals , Anti-Bacterial Agents/pharmacology , Bacterial Proteins , Caenorhabditis elegans , Imipenem/pharmacology , Lactams , Mice , Microbial Sensitivity Tests , beta-Lactamases/genetics
13.
Phys Rev Lett ; 127(21): 213902, 2021 Nov 19.
Article in English | MEDLINE | ID: mdl-34860072

ABSTRACT

Monolithic optical parametric oscillators extend laser frequencies in compact architectures, but normally guide and circulate all pump, signal, and idler beams. Critical frequency matching is raised among these resonances, limiting operation stability and continuous tuning. Here, we develop a box resonator geometry that guides all beams but only resonates for signal. Such noncritical frequency matching enables 227 GHz continuous tuning, with sub-10 kHz linewidth and 0.43 W power at 3310 nm. Our results confirm that monolithic resonator can be effectively used as a tunable laser including midinfrared wavelength, as further harnessed with methane fine spectral measurement at MHz accuracy.

14.
Opt Lett ; 45(15): 4184-4187, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-32735254

ABSTRACT

We analytically and numerically unveil the existence condition of symbiotic solitons in doubly resonant non-degenerate optical parametric oscillators. Resonant signal and idler with terahertz comb bandwidth and femtosecond pulse duration in the mid-infrared are attainable through this symbiotic soliton mode-locking technique. The group velocity mismatches between the three interacting waves are the dominant cause of the symbiotic soliton perturbation, and their effects are numerically investigated in detail. The principle can be applied to commonly used mid-infrared material platforms, making it a competitive ultrashort pulse and broadband comb source architecture.

15.
Opt Lett ; 45(8): 2311-2314, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-32287221

ABSTRACT

We examine the existence condition of the quadratic soliton mode-locked degenerate optical parametric oscillator in the previously unexplored parameter space. We study the nature of the quadratic solitons and divide their dynamics into two distinctive branches, depending on the system parameters. Origin of the quadratic soliton perturbation is identified, and strategy to mitigate its detrimental effect is developed. Frequency comb with terahertz bandwidth and femtosecond pulse duration are attainable in an example periodically poled lithium niobate waveguide resonator. Design rules of the quadratic soliton mode-locking are summarized. The principle can be further extended to other material platforms, making it a competitive ultrashort pulse and broadband comb source architecture at the mid-infrared.

16.
Phys Rev Lett ; 125(14): 143902, 2020 Oct 02.
Article in English | MEDLINE | ID: mdl-33064523

ABSTRACT

We demonstrate the first compact photonic flywheel with sub-fs time jitter (averaging times up to 10 µs) at the quantum-noise limit of a monolithic fiber resonator. Such quantum-limited performance is accessed through novel two-step pumping scheme for dissipative Kerr soliton generation. Controllable interaction between stimulated Brillouin lasing and Kerr nonlinearity enhances the DKS coherence and mitigates the thermal instability challenge, achieving a remarkable 22-Hz intrinsic comb linewidth and an unprecedented phase noise of -180 dBc/Hz at 945-MHz carrier at free running. The scheme can be generalized to various device platforms for field-deployable precision metrology.

17.
Int J Mol Sci ; 21(12)2020 Jun 16.
Article in English | MEDLINE | ID: mdl-32560269

ABSTRACT

There have been many microfluid technologies combined with hanging-drop for cell culture gotten developed in the past decade. A common problem within these devices is that the cell suspension introduced at the central inlet could cause a number of cells in each microwell to not regularize. Also, the instability of droplets during the spheroid formation remains an unsolved ordeal. In this study, we designed a microfluidic-based hanging-drop culture system with the design of taper-tube that can increase the stability of droplets while enhancing the rate of liquid exchange. A ring is surrounding the taper-tube. The ring can hold the cells to enable us to seed an adequate amount of cells before perfusion. Moreover, during the period of cell culture, the mechanical force around the cell is relatively low to prevent stem cells from differentiate and maintain the phenotype. As a result of our hanging system design, cells are designed to accumulate at the bottom of the droplet. This method enhances convenience for observation activities and analysis of experiments. Thus, this microfluid chip can be used as an in vitro platform representing in vivo physiological conditions, and can be useful in regenerative therapy.


Subject(s)
Cell Culture Techniques/instrumentation , Mesenchymal Stem Cells/cytology , Microfluidic Analytical Techniques/instrumentation , Biomimetic Materials/chemistry , Cell Proliferation , Cell Survival , Cells, Cultured , Culture Media/chemistry , Humans , Phenotype
18.
Int J Mol Sci ; 21(10)2020 May 21.
Article in English | MEDLINE | ID: mdl-32455543

ABSTRACT

The interference screw fixation method is used to secure a graft in the tibial tunnel during anterior cruciate ligament reconstruction surgery. However, several complications have been reported, such as biodegradable screw breakage, inflammatory or foreign body reaction, tunnel enlargement, and delayed graft healing. Using additive manufacturing (AM) technology, we developed a titanium alloy (Ti6Al4V) interference screw with chemically calcium phosphate surface modification technology to improve bone integration in the tibial tunnel. After chemical and heat treatment, the titanium screw formed a dense apatite layer on the metal surface in simulated body fluid. Twenty-seven New Zealand white rabbits were randomly divided into control and additive manufactured (AMD) screw groups. The long digital extensor tendon was detached and translated into a tibial plateau tunnel (diameter: 2.0 mm) and transfixed with an interference screw while the paw was in dorsiflexion. Biomechanical analyses, histological analyses, and an imaging study were performed at 1, 3, and 6 months. The biomechanical test showed that the ultimate pull-out load failure was significantly higher in the AMD screw group in all tested periods. Micro-computed tomography analyses revealed early woven bone formation in the AMD screw group at 1 and 3 months. In conclusion, AMD screws with bioactive surface modification improved bone ingrowth and enhanced biomechanical performance in a rabbit model.


Subject(s)
Bone Screws/standards , Osseointegration , Printing, Three-Dimensional , Tendons/surgery , Tibia/surgery , Alloys/chemistry , Animals , Bone Screws/adverse effects , Bone-Implant Interface/surgery , Calcium Phosphates/chemistry , Porosity , Rabbits
19.
Molecules ; 24(9)2019 May 08.
Article in English | MEDLINE | ID: mdl-31072045

ABSTRACT

A novel sensing system has been designed for the detection of cupric ions. It is based on the quenched fluorescence signal of carbon dots (CDs), which were carbonized from poly(vinylpyrrolidone) (PVP) and L-Cysteine (CYS). Cupric ions interact with the nitrogen and sulfur atoms on surface of the CDs to form an absorbed complex; this results in strong quenching of the fluorescence of the CDs via a fast metal-to-ligand binding affinity. The synthesized water-soluble CDs also exhibited a quantum yield of 7.6%, with favorable photoluminescent properties and good photostability. The fluorescence intensity of the CDs was very stable in high ionic strength (up to 1.0 M NaCl) and over a wide range of pH levels (2.0-12.0). This facile method can therefore develop a sensor that offers reliable, fast, and selective detection of cupric ions with a detection limit down to 0.15 µM and a linear range from 0.5 to 7.0 µM (R2 = 0.980). The CDs were used for cell imaging, observed that they were low toxicity to Tramp C1 cells and exhibited blue and green and red fluorescence under a fluorescence microscope. In summary, the CDs exhibited excellent fluorescence properties, and could be applied to the selective and sensitive detection of cupric ion and multicolor cell imaging.


Subject(s)
Carbon/chemistry , Copper/analysis , Imaging, Three-Dimensional/methods , Molecular Probes/chemical synthesis , Quantum Dots/chemistry , Animals , Carbon/toxicity , Cell Death/drug effects , Cell Line, Tumor , Cell Survival/drug effects , Fluorescence , Ions , Mice, Transgenic , Molecular Probes/chemistry , Photoelectron Spectroscopy , Quantum Dots/toxicity , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Spectroscopy, Fourier Transform Infrared , Water Pollutants, Chemical/analysis
20.
Opt Lett ; 43(10): 2406-2409, 2018 May 15.
Article in English | MEDLINE | ID: mdl-29762604

ABSTRACT

We demonstrate seamless channel multiplexing and high bitrate superchannel transmission of coherent optical orthogonal frequency division multiplexing (CO-OFDM) data signals utilizing a dissipative Kerr soliton (DKS) frequency comb generated in an on-chip microcavity. Aided by comb line multiplication through Nyquist pulse modulation, the high stability and mutual coherence among mode-locked Kerr comb lines are exploited for the first time, to the best of our knowledge, to eliminate the guard intervals between communication channels and achieve full spectral density bandwidth utilization. Spectral efficiency as high as 2.625 bit/Hz/s is obtained for 180 CO-OFDM bands encoded with 12.75 Gbaud 8-QAM data, adding to the total bitrate of 6.885 Tb/s within a 2.295 THz frequency comb bandwidth. This Letter confirms that high coherence is the key superiority of Kerr soliton frequency combs over independent laser diodes, as a multi-spectral coherent laser source for high-bandwidth high-spectral-density transmission networks.

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