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1.
Zhonghua Er Ke Za Zhi ; 62(8): 770-774, 2024 Jul 23.
Article in Chinese | MEDLINE | ID: mdl-39039880

ABSTRACT

Objective: To summarize the clinical characteristics of patients with end-stage heart failure who receive heart transplant under extracorporeal membrane oxygenation (ECMO) support. Methods: The clinical data of 12 pediatric patients who received heart transplant with ECMO support in the Seventh Medical Center of Chinese People's Liberation Army General Hospital and Guangdong Provincial People's Hospital, from January 2019 to December 2023 was collected. The data included sex, age, weight, diagnosis, pre-ECMO lactate level, left ventricular ejection fraction (LVEF), vasoactive-inotropic score (VIS), and preoperative ECMO running time. Surgical data included cold ischemia time of the donor heart, cardiopulmonary bypass time, intraoperative use of immunosuppressant, postoperative use of ECMO, duration of postoperative ECMO, rate of successful weaning from ECMO, and survival discharge rate. The paired t-test was performed to compare cardiac function indices before and after left ventricular decompression. Results: The 12 patients ranged in age from 1.1 to 15.8 years, and weighted from 8 to 63 kg. Ten children were diagnosed with dilated cardiomyopathy, one with myocardial underdensification, and one with a novel heterozygous mutation of the SCN5A gene causing overlap syndrome complicated by fatal arrhythmia. Before ECMO, the lactate ranged from 0.6 to>15.0 mmol/L, the LVEF from 6.5% to 43%, and VIS from 3 to 108. Four patients underwent left ventricular decompression supported by preoperative ECMO, and their pulse pressure was significantly increased after decompression ((17.8±2.1) vs. (9.8±1.5) mmHg, 1 mmHg=0.133 kPa, t=11.31, P=0.001), while there was no apparent change in LVEF ((26.8±4.4)% vs. (24.9±4.9)%, t=1.75, P=0.178). A total of 7 children received a second run of ECMO after surgery and 3 of them successfully weaned off ECMO and survived to discharge. In the entire cohort, 10 were successfully weaned from ECMO and 8 survived to discharge. Conclusions: For children with end-stage heart failure supported by ECMO, left ventricular decompression can significantly improve pulse pressure. These patients will eventually require heart transplantation.

2.
Zhonghua Er Ke Za Zhi ; 62(7): 661-668, 2024 Jul 02.
Article in Chinese | MEDLINE | ID: mdl-38955685

ABSTRACT

Objective: To explore the factors affecting the prognosis of severe pediatric acute respiratory distress syndrome (ARDS) after receiving extracorporeal membrane oxygenation (ECMO) support. Methods: It was a multicenter prospective observational study. A total of 95 children with severe ARDS who were treated with ECMO salvage therapy from January 2018 to December 2022 in 9 pediatric ECMO centers in China were enrolled in the study. The general data, disease severity, organ function, comprehensive treatment and prognosis were recorded, and they were divided into survival group and death group according to the outcome at discharge. T test, chi-square test, multivariate Logistic regression and mixed linear model were used to analyze the relationship among baseline before ECMO treatment, some important indicators (pediatric critical scores, platelet count, albumin, fibrinogen, etc) during ECMO treatment and prognosis. Results: Among the 95 children with severe ARDS who received ECMO, 55 (58%) were males and 40 (42%) were females, aged 36.9 (0.5, 72.0) months. Twelve children (13%) were immunodeficient. Sixty-eight (72%) children were treated with venous artery (VA) mode and 27 (28%) with venous vein (VV) mode. The discharge survival rates of overall, VA, and VV mode children were 51% (48/95), 47% (32/68), and 59% (16/27), respectively. The number of immunodeficient children in the death group was higher, and there were lower pediatric critical scores, platelet count, albumin, fibrinogen and arterial oxygen partial pressure/fraction of inspired oxygen (PaO2/FiO2), higher ventilator driving pressure (ΔP), oxygenaion index (OI), and longer ARDS duration before ECMO (all P<0.05). There were no statistically significant differences in other indicators, including age, gender, weight, and ECMO mode among different prognostic groups (all P>0.05). High ΔP, high OI, low P/F, and low albumin were high-risk factors affecting prognosis(all P<0.05). After further grouping, it was found that ΔP≥25 cmH2O (1 cmH2O=0.098 kPa), P/F≤67 mmHg (1 mmHg=0.133 kPa) and OI≥35 were the thresholds for predicting poor prognosis (P<0.05). From 24 h after ECMO, there were significant differences in ΔP, P/F and OI between the dead group and the survival group (all P<0.05), and the differences gradually increased with the ECMO process. The platelet level was significant from 7 days after ECMO (P<0.05) and gradually expanded. Blood lactate levels showed a significant difference between the 2 groups on before and after ECMO (P<0.05) and gradually increased from 24 h after ECMO. Conclusions: The risk factors affecting the prognosis of severe ARDS in ECMO include high ΔP, high OI, low P/F and low albumin purification therapy before ECMO. The gradual decrease of ΔP, OI and increase of P/F from 24 h of ECMO predicted a good prognosis, while the gradual increase of lactate after ECMO application showed a poor prognosis.


Subject(s)
Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Humans , Extracorporeal Membrane Oxygenation/methods , Male , Female , Prognosis , Prospective Studies , Child, Preschool , Infant , Child , Respiratory Distress Syndrome/therapy , Respiratory Distress Syndrome/mortality , Survival Rate , Severity of Illness Index , China , Platelet Count , Infant, Newborn
3.
Opt Express ; 32(11): 20146-20152, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38859131

ABSTRACT

Sapphire is a promising wideband substrate material for visible photonics. It is a common growth substrate for III-nitride light-emitting diodes and laser structures. Doped sapphires are important gain media foundational to the development of titanium-sapphire and ruby lasers. For lasers operating at visible and near-infrared wavelengths, a photonic platform that minimizes loss while maximizing gain material overlap is crucial. Here, we introduce a novel low-loss waveguiding strategy that establishes high-performance integrated photonics on sapphire substrates. This platform achieves a high intrinsic quality factor of 5.6 million near 780 nm and features direct compatibility with a range of solid-state laser gain media.

5.
Nan Fang Yi Ke Da Xue Xue Bao ; 44(2): 381-386, 2024 Feb 20.
Article in Chinese | MEDLINE | ID: mdl-38501424

ABSTRACT

OBJECTIVE: To investigate the mechanism of tea polyphenols (TP) for regulating NLRP3 inflammasomes and alleviating acute lung injury in septic mice. METHODS: Sixty C57BL/6 mice were randomly assigned into sham-operated, cecal ligation and puncture (CLP) and CLP +TP treatment groups, and survival of the mice was recorded after modeling in each group. The lung wet/dry weight ratio and myeloperoxidase (MPO) activity were determined, and lung injury of the mice was evaluated using HE staining and acute lung injury score. The expressions of IL-1ß, TNF-α, IL-6, NLRP3, caspase-1 p10, ASC, MPO, and caspase-8 in the lung tissue were detected using ELISA, Western blotting, or immunohistochemical staining. MDA and H2O2 levels in the lungs were detected to evaluate the level of oxidative stress. Immunofluorescence assay was used to investigate the co-localization of NLRP3 and NOX4. RESULTS: The postoperative mortality rate at 72 h, lung wet/dry weight ratio, MPO level and acute lung injury scores were significantly lower in CLP+TP group than in CLP group (P < 0.05). Treatment with TP significantly reduced the expressions of NLRP3-related inflammatory factors (P < 0.05) and lowered MDA and H2O2 levels in the lung tissue of the septic mice (P < 0.05). Immunofluorescence co-staining showed a lower level of NOX4 and NLRP3 co-localization in CLP+TP group than in CLP group. CONCLUSION: TP inhibits NLRP3 inflammasome-associated inflammation to alleviate CLP-induced acute lung injury in mice through a regulatory mechanism that inhibits NOX4 expression and reduces oxidative stress in the lung tissue.


Subject(s)
Acute Lung Injury , Sepsis , Mice , Animals , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Hydrogen Peroxide , Mice, Inbred C57BL , Acute Lung Injury/drug therapy , Lung/metabolism , Sepsis/drug therapy , Sepsis/metabolism , Tea
6.
medRxiv ; 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38496516

ABSTRACT

Study Question: What is the impact of the presence of uterine fibroids on the risk of developing hypertensive disorders of pregnancy (HDP) in a predominantly urban, low-income, Black, and Hispanic population of women with ultrasound or clinically diagnosed uterine fibroids with rich phenotypic data to carefully control for potential confounders? Summary answers: The odds of HDP were 39% higher in women with uterine fibroids compared to those without when controlled for age at delivery, race, prepregnancy BMI, education, parity, and smoking status; neither fibroid location or size modified this risk. What is known already: Studies are conflicting regarding the impact of uterine fibroids on risk of HDP; limitations of prior studies include primarily Western European populations and lack of measurement of potential confounders. Study design size and duration: A total of 7030 women from the Boston Birth Cohort (a racially diverse cohort recruited from 1998 to 2018) that had clinical and ultrasound data regarding uterine fibroid status were included in this analysis. Participants/materials setting and methods: Four hundred eighty-nine women with uterine fibroids and 6541 women without were included. Hypertensive disorders of pregnancy were ascertained from medical records. Logistic regression was performed to assess the risk of HDP in women with and without uterine fibroids. Covariates adjusted for included age at delivery, race, pre-pregnancy BMI, education, parity, and smoking status during pregnancy. Sub-analyses were performed to assess the impact of specific fibroid location and overall fibroid volume burden. Main results and the role of chance: The incidence of uterine fibroids in the cohort was 7% (N=489). Twelve percent of women without uterine fibroids and 17% of women with fibroids developed HDP; in multivariate analyses adjusted for the potential confounders above, the odds of HDP were 39% higher in women with uterine fibroids compared to those without (p=0.03). Women with a uterine fibroid diagnosis based on ICD code (n=297) versus asymptomatic incidental ultrasound diagnosis (n=192) had a significantly greater chance of developing HDP (20 vs 15%, p=0.006). There did not appear to be an association between number of fibroids or total fibroid volume and the risk of developing HDP. Limitations, reasons for caution: This study has a relatively small sample size. While post-hoc power calculation determined that there was adequate power to detect a 4.6% difference in the incidence of development of HDP between participants with uterine fibroids and those without, the sub-analyses based on fibroid size, location, and method of diagnosis were underpowered to determine a similar level of difference. Wider implications of the findings: In a racially diverse cohort, presence of uterine fibroids was a significant risk factor for developing HDP, regardless of uterine fibroid size or location. This may have implications for additional monitoring and risk stratification in women with uterine fibroids. Study funding/competing interests: KC supported by WRHR NIH NICHD Award # K12 HD103036, PI Andrew Satin, RD James Segars. The Boston Birth Cohort (the parent study) was supported in part by the National Institutes of Health (NIH) grants (2R01HD041702, R01HD098232, R01ES031272, R01ES031521, and U01 ES034983); and the Health Resources and Services Administration (HRSA) of the U.S. Department of Health and Human Services (HHS) (UT7MC45949). This information or content and conclusions are those of the authors and should not be construed as the official position or policy of, nor should any endorsements be inferred by any funding agencies. Trial registration number: The BBC is registered under clinicaltrials.gov NCT03228875 .

7.
Clin Radiol ; 79(5): e750-e758, 2024 May.
Article in English | MEDLINE | ID: mdl-38360515

ABSTRACT

AIM: To investigate the application of the T2-weighted (T2)-fluid-attenuated inversion recovery (FLAIR) mismatch sign and machine learning-based multiparametric magnetic resonance imaging (MRI) radiomics in predicting 1p/19q non-co-deletion of lower-grade gliomas (LGGs). MATERIALS AND METHODS: One hundred and forty-six patients, who had pathologically confirmed isocitrate dehydrogenase (IDH) mutant LGGs were assigned randomly to the training cohort (n=102) and the testing cohort (n=44) at a ratio of 7:3. The T2-FLAIR mismatch sign and conventional MRI features were evaluated. Radiomics features extracted from T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), FLAIR, apparent diffusion coefficient (ADC), and contrast-enhanced T1WI images (CE-T1WI). The models that displayed the best performance of each sequence were selected, and their predicted values as well as the T2-FLAIR mismatch sign data were collected to establish a final stacking model. Receiver operating characteristic curve (ROC) analyses and area under the curve (AUC) values were applied to evaluate and compare the performance of the models. RESULTS: The T2-FLAIR mismatch sign was more common in the IDH mutant 1p/19q non-co-deleted group (p<0.05) and the area under the curve (AUC) value was 0.692 with sensitivity 0.397, specificity 0.987, and accuracy 0.712, respectively. The stacking model showed a favourable performance with an AUC of 0.925 and accuracy of 0.882 in the training cohort and an AUC of 0.886 and accuracy of 0.864 in the testing cohort. CONCLUSION: The stacking model based on multiparametric MRI can serve as a supplementary tool for pathological diagnosis, offering valuable guidance for clinical practice.


Subject(s)
Brain Neoplasms , Glioma , Multiparametric Magnetic Resonance Imaging , Humans , Isocitrate Dehydrogenase/genetics , Radiomics , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Mutation/genetics , Glioma/diagnostic imaging , Glioma/genetics , Glioma/pathology , Magnetic Resonance Imaging/methods , Machine Learning , Retrospective Studies
9.
BMC Cardiovasc Disord ; 24(1): 109, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38355415

ABSTRACT

BACKGROUND: Early diagnosis of atrial fibrillation is important as it is crucial for improving patient outcomes. Fibroblast growth factor-2 (FGF2) may serve as a diagnostic biomarker for heart failure due to its ability to promote cardiac fibrosis and hypertrophy; however, the relationship between FGF2 concentration and heart failure is unclear. Therefore, this study aimed to explore whether FGF2 could aid in distinguishing patients with heart failure from healthy controls and those with dyspnea without heart failure. Additionally, to evaluate the possible correlation between serum FGF2 levels and its diagnostic parameters in patients with heart failure. METHODS: Plasma FGF2 concentration was measured in 114 patients with a complaint of dyspnea (enrolled in the study between January 2022 and August 2022). Based on heart failure diagnosis, the patients were assigned to three groups, as follows: heart failure (n = 80), non-heart-failure dyspnea (n = 34), and healthy controls (n = 36), following physical examination. Possible correlations between serum FGF2 levels and other prognostic parameters in patients with heart failure were analyzed. RESULTS: Serum FGF2 levels were higher in patients with heart failure (125.60 [88.95, 183.40] pg/mL) than in those with non-heart-failure dyspnea (65.30 [28.85, 78.95] pg/mL) and healthy controls (78.90 [60.80, 87.20] pg/mL) (p < 0.001). Receiver operating characteristic curve analysis identified FGF2 concentration as a significant predictor in heart failure diagnosis, with an area under the curve of 0.8693 (p < 0.0001). Importantly, in the heart failure group, serum FGF2 concentrations correlated with key prognostic parameters for heart failure, such as reduced left ventricular ejection fraction and elevated serum levels of N-terminal pro-B-type natriuretic peptide. CONCLUSIONS: Elevated serum FGF2 level is strongly associated with an increased risk of heart failure and could serve as a useful biomarker to complement vital diagnostic parameters for heart failure.


Subject(s)
Fibroblast Growth Factor 2 , Heart Failure , Humans , Stroke Volume , Ventricular Function, Left , Biomarkers , Natriuretic Peptide, Brain , Peptide Fragments , Dyspnea/diagnosis , Dyspnea/etiology
10.
J Endocrinol Invest ; 47(3): 535-546, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37524979

ABSTRACT

PURPOSE: Diabetes and dyslipidemia are among the most common chronic diseases with increasing global disease burdens, and they frequently occur together. The study aimed to investigate differences in the heritability of glycemic traits and serum lipid indicators and differences in overlapping genetic and environmental influences between them across age groups. METHODS: This study included 1189 twin pairs from the Chinese National Twin Registry and divided them into three groups: aged ≤ 40, 41-50, and > 50 years old. Univariate and bivariate structural equation models (SEMs) were conducted on glycemic indicators and serum lipid indicators, including blood glucose (GLU), glycated hemoglobin A1c (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), in the total sample and three age groups. RESULTS: All phenotypes showed moderate to high heritability (0.37-0.64). The heritability of HbA1c demonstrated a downward trend with age (HbA1c: 0.50-0.79), while others remained relatively stable (GLU: 0.55-0.62, TC: 0.58-0.66, TG: 0.50-0.63, LDL-C: 0.24-0.58, HDL-C: 0.31-0.57). The bivariate SEMs demonstrated that GLU and HbA1c were correlated with each serum lipid indicator (0.10-0.17), except HDL-C. Except for HbA1c and LDL-C, as well as HbA1c and HDL-C, differences in genetic correlations underlying glycemic traits and serum lipids between age groups were observed, with the youngest group showing a significantly higher genetic correlation than the oldest group. CONCLUSION: Across the whole adulthood, genetic influences were consistently important for GLU, TC, TG, LDL-C and HDL-C, and age may affect the shared genetic influences between glycemic traits and serum lipids. Further studies are needed to elucidate the role of age in the interactions of genes related to glycemic traits and serum lipids.


Subject(s)
Blood Glucose , Lipids , Adult , Humans , Middle Aged , Causality , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Phenotype , Triglycerides/blood , East Asian People , Glycated Hemoglobin , Lipids/blood
11.
Clin Oncol (R Coll Radiol) ; 36(1): e20-e30, 2024 01.
Article in English | MEDLINE | ID: mdl-37993317

ABSTRACT

AIMS: The aim of this systematic review with meta-analysis was to evaluate the efficacy and safety of programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) checkpoint inhibitors in patients with metastatic castration-resistant prostate cancer (mCRPC). MATERIALS AND METHODS: We searched PubMed, Embase and Cochrane Library until 1 July 2022 for mCRPC trials testing PD-1/PD-L1 checkpoint inhibitors. We measured the efficacy and safety using overall survival, progression-free survival (PFS), overall response rates (ORR), prostate-specific antigen (PSA) response rate or treatment-related adverse events (TRAEs). When possible, data were meta-analysed. RESULTS: Thirteen studies involving 2533 participants were included in this meta-analysis. The pooled hazard ratio for overall survival was 0.81 (95% confidence interval 0.42-1.20, I2 = 80.3%, PHeterogeneity<0.001) and for PFS was 0.65 (95% confidence interval 0.38-0.92, I2 = 72.2%, PHeterogeneity = 0.013). Furthermore, better ORR (relative risk = 2.77, 95% confidence interval 1.25-6.13, I2 = 0%, PHeterogeneity = 0.699) was found in PD-L1-expressing tumours. However, no statistical trends between PD-L1 status on PSA response rate (relative risk = 0.79, 95% confidence interval 0.5-1.25, I2 = 0%, PHeterogeneity = 0.953) and tumour mutational burden on ORR (relative risk = 2.53, 95% confidence interval 0.49-13.12, I2 = 74.5%, PHeterogeneity = 0.02) were observed. The pooled proportions of TRAEs and ≥ grade 3 TRAEs were 85.1% (95% confidence interval = 71.7-98.5%) and 31.6% (95% confidence interval = 18.9-44.4%), respectively. CONCLUSIONS: This meta-analysis showed that among selected populations of men with mCRPC, anti-PD-1/PD-L1 combination treatment may significantly increase the PFS benefits. However, overall survival in mCRPC warrants further testing.


Subject(s)
Programmed Cell Death 1 Receptor , Prostatic Neoplasms, Castration-Resistant , Male , Humans , Prostatic Neoplasms, Castration-Resistant/drug therapy , Prostatic Neoplasms, Castration-Resistant/genetics , B7-H1 Antigen , Prostate-Specific Antigen , Ligands , Immune Checkpoint Inhibitors
12.
Opt Express ; 31(21): 33923-33929, 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37859161

ABSTRACT

UV and visible photonics enable applications ranging from spectroscopic sensing to communication and quantum information processing. Photonics structures in these wavelength regimes, however, tend to experience higher loss than their IR counterpart. Particularly in the near-UV band, on-chip optical microresonators have not yet achieved a quality factor beyond 1 million. Here, we report ultra-low-loss photonic waveguides and resonators patterned from alumina thin films prepared by a highly scalable atomic layer deposition process. We demonstrate ultra high Q factor of 1.5×106 at 390 nm, a record value at UV bands, and 1.9×106 at 488.5 nm.

13.
Zhonghua Er Ke Za Zhi ; 61(11): 1018-1023, 2023 Nov 02.
Article in Chinese | MEDLINE | ID: mdl-37899341

ABSTRACT

Objectives: To investigate the current application status and implementation difficulties of extracorporeal cardiopulmonary resuscitation (ECPR) in children with sudden cardiac arrest. Methods: This cross-sectional survey was conducted in 35 hospitals. A Children's ECPR Information Questionnaire on the implementation status of ECPR technology (abbreviated as the questionnaire) was designed, to collect the data of 385 children treated with ECPR in the 35 hospitals. The survey extracted the information about development of ECPR, the maintenance of extracorporeal membrane oxygenation (ECMO) machine, the indication of ECPR, and the difficulties of implementation in China. These ECPR patients were grouped based on their age, the hospital location and level, to compare the survival rates after weaning and discharge. The statistical analysis used Chi-square test and one-way analysis of variance for the comparison between the groups, LSD method for post hoc testing, and Bonferroni method for pairwise comparison. Results: Of the 385 ECPR cases, 224 were males and 161 females. There were 185 (48.1%) survival cases after weaning and 157 (40.8%) after discharge. There were 324 children (84.2%) receiving ECPR for cardiac disease and 27 children (7.0%) for respiratory failure. The primary cause of death in ECPR patients was circulatory failure (82 cases, 35.9%), followed by brain failure (80 cases, 35.0%). The most common place of ECPR was intensive care unit (ICU) (278 cases, 72.2%); ECPR catheters were mostly inserted through incision (327 cases, 84.9%). There were 32 hospitals (91.4%) had established ECMO emergency teams, holding 125 ECMO machines in total. ECMO machines mainly located in ICU (89 pieces, 71.2%), and the majority of hospitals (32 units, 91.4%) did not have pre-charged loops. There were no statistically significant differences in the post-withdrawal and post-discharge survival rates of ECPR patients among different age groups, regions, and hospitals (all P>0.05). The top 5 difficulties in implementing ECPR in non-ICU environments were lack of ECMO machines (16 times), difficulty in placing CPR pipes (15 times), long time intervals between CPR and ECMO transfer (13 times), lack of conventional backup ECMO loops (10 times), and inability of ECMO emergency teams to quickly arrive at the site (5 times). Conclusion: ECPR has been gradually developed in the field of pediatric critical care in China, and needs to be further standardized. ECPR in non-ICU environment remains a challenge.


Subject(s)
Cardiopulmonary Resuscitation , Heart Arrest , Child , Female , Humans , Male , Aftercare , Cardiopulmonary Resuscitation/methods , Cross-Sectional Studies , Death, Sudden, Cardiac/prevention & control , East Asian People , Heart Arrest/therapy , Patient Discharge , Retrospective Studies , Surveys and Questionnaires
14.
J Med Chem ; 66(15): 10150-10201, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37528515

ABSTRACT

Each year, new drugs are introduced to the market, representing structures that have affinity for biological targets implicated in human diseases and conditions. These new chemical entities (NCEs), particularly small molecules and antibody-drug conjugates, provide insight into molecular recognition and serve as potential leads for the design of future medicines. This annual review is part of a continuing series highlighting the most likely process-scale synthetic approaches to 35 NCEs that were first approved anywhere in the world during 2021.


Subject(s)
Drug Design , Humans , Pharmaceutical Preparations , Immunoconjugates/chemistry
15.
Nat Commun ; 14(1): 2798, 2023 May 16.
Article in English | MEDLINE | ID: mdl-37193684

ABSTRACT

Frequency conversion of dissipative solitons associated with the generation of broadband optical frequency combs having a tooth spacing of hundreds of giga-hertz is a topical challenge holding the key to practical applications in precision spectroscopy and data processing. The work in this direction is underpinned by fundamental problems in nonlinear and quantum optics. Here, we present the dissipative two-colour bright-bright and dark-dark solitons in a quasi-phase-matched microresonator pumped for the second-harmonic generation in the near-infrared spectral range. We also found the breather states associated with the pulse front motion and collisions. The soliton regime is found to be typical in slightly phase-mismatched resonators, while the phase-matched ones reveal broader but incoherent spectra and higher-order harmonic generation. Soliton and breather effects reported here exist for the negative tilt of the resonance line, which is possible only via the dominant contribution of second-order nonlinearity.

16.
Nat Commun ; 14(1): 1718, 2023 Mar 28.
Article in English | MEDLINE | ID: mdl-36977681

ABSTRACT

Rare earth emitters enable critical quantum resources including spin qubits, single photon sources, and quantum memories. Yet, probing of single ions remains challenging due to low emission rate of their intra-4f optical transitions. One feasible approach is through Purcell-enhanced emission in optical cavities. The ability to modulate cavity-ion coupling in real-time will further elevate the capacity of such systems. Here, we demonstrate direct control of single ion emission by embedding erbium dopants in an electro-optically active photonic crystal cavity patterned from thin-film lithium niobate. Purcell factor over 170 enables single ion detection, which is verified by second-order autocorrelation measurement. Dynamic control of emission rate is realized by leveraging electro-optic tuning of resonance frequency. Using this feature, storage, and retrieval of single ion excitation is further demonstrated, without perturbing the emission characteristics. These results promise new opportunities for controllable single-photon sources and efficient spin-photon interfaces.

18.
Zhonghua Gan Zang Bing Za Zhi ; 31(11): 1182-1186, 2023 Nov 20.
Article in Chinese | MEDLINE | ID: mdl-38238952

ABSTRACT

Objective: To investigate the role of serum hepatitis B virus RNA (HBV RNA) in predicting HBeAg serological conversion in children with chronic hepatitis B. Methods: 175 children aged 1~17 years with chronic hepatitis B who received interferon α (IFNα) for 48 weeks were selected. Patients were divided into HBeAg seroconversion and non-conversion based on whether HBeAg seroconversion occurred at 48 weeks of treatment.T-test and Mann-Whitney U test were used to compare between groups; chisquare test or Fisher exact probability method was used to compare the frequency between groups of classified variables; and Pearson correlation was used to analyze the correlation between indicators. Univariate and multivariate logistic regression analyses were used to identify influencing factors associated with HBeAg serological conversion. The predictive effect of HBV RNA, HBV DNA, and HBsAg on HBeAg serological conversion was compared and analyzed by the receiver operating characteristic curve (ROC). Results: The seroconversion rate of HBeAg at 48 weeks was 36.0% (63/175). The reduction in HBVRNA levels from baseline to the 12th, 24th, 36th, and 48th weeks of antiviral therapy was significantly greater in the HBeAg serological conversion group than that in the non-conversion group, and the difference was statistically significant between the two groups (P < 0.05). Univariate and multivariate regression analyses showed that age and a decline in HBV RNA levels at week 12 were independent predictors of HBeAg serological conversion. The area under the ROC curve (AUROC) of HBV RNA decline at week 12 was 0.677(95% CI∶0.549-0.806, P = 0.012), which was significantly better than the same period of AUROC of HBV DNA (0.657, 95% CI∶0.527-0.788, P = 0.025) and HBsAg (0.660, 95% CI∶0.526-0.795, P = 0.023) decline. HBV RNA levels decreased (>1.385 log10 copies/ml) at week 12, with a positive predictive value of 53.2%, a negative predictive value of 72.2%, a sensitivity of 77.4%, and a specificity of 57.9% for HBeAg seroconversion. Conclusion: HBV RNA level lowering during the 12th week of antiviral therapy can serve as an early predictor marker for HBeAg serological conversion in children with chronic hepatitis B.


Subject(s)
Hepatitis B virus , Hepatitis B, Chronic , Child , Humans , Hepatitis B e Antigens , Hepatitis B Surface Antigens , Antiviral Agents/therapeutic use , DNA, Viral , RNA, Viral , Treatment Outcome
19.
Phys Rev Lett ; 129(16): 167201, 2022 Oct 14.
Article in English | MEDLINE | ID: mdl-36306770

ABSTRACT

The everlasting interest in spin chains is mostly rooted in the fact that they generally allow for comparisons between theory and experiment with remarkable accuracy, especially for exactly solvable models. A notable example is the spin-1/2 antiferromagnetic Heisenberg chain (AFHC), which can be well described by the Tomonaga-Luttinger liquid theory and exhibits fractionalized spinon excitations with distinct thermodynamic and spectroscopic experimental signatures consistent with theoretical predictions. A missing piece, however, is the lack of a comprehensive understanding of the spinon heat transport in AFHC systems, due to difficulties in its experimental evaluation against the backdrop of other heat carriers and complex scattering processes. Here we address this situation by performing ultralow-temperature thermal conductivity measurements on a nearly ideal spin-1/2 AFHC system copper benzoate Cu(C_{6}H_{5}COO)_{2}·3H_{2}O, whose field-dependent spin excitation gap enables a reliable extraction of the spinon thermal conductivity κ_{s} at zero field. κ_{s} was found to exhibit a linear temperature dependence κ_{s}∼T at low temperatures, with κ_{s}/T as large as 1.70 mW cm^{-1} K^{-2}, followed by a precipitate decline below ∼0.3 K. The observed κ_{s}∼T clarifies the discrepancies between various spin chain systems and serves as a benchmark for one-dimensional spinon heat transport in the low-temperature limit. The abrupt loss of κ_{s} with no corresponding anomaly in the specific heat is discussed in the context of many-body localization.

20.
Phys Rev Lett ; 129(10): 107701, 2022 Sep 02.
Article in English | MEDLINE | ID: mdl-36112440

ABSTRACT

We present a nonlinear multimode superconducting electroacoustic system, where the interplay between superconducting kinetic inductance and piezoelectric strong coupling establishes an effective Kerr nonlinearity among multiple acoustic modes at 10 GHz that could hardly be achieved via intrinsic mechanical nonlinearity. By exciting this multimode Kerr system with a single microwave tone, we further demonstrate a coherent electroacoustic frequency comb and provide theoretical understanding of multimode nonlinear interaction in the superstrong coupling limit. This nonlinear superconducting electroacoustic system sheds light on the active control of multimode resonator systems and offers an enabling platform for the dynamic study of microcombs at microwave frequencies.

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