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1.
Opt Express ; 30(18): 33124-33135, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242359

RESUMO

An asymmetric point-to-multipoint (PTMP) coherent architecture combined with a frequency aliasing recovery (FAR) algorithm is proposed for cost-constraint short-reach access networks. In this architecture, the uplink transmitters are simplified significantly with the uplink dual-polarization four-level pulse amplitude modulation (DP-PAM4) and downlink DP quadrature phase shift keying (DP-QPSK) asymmetric transmission design. Digital to analog converters (DACs) and radio frequency (RF) drivers are reduced by half, and in-phase and quadrature modulators (IQMs) are replaced by Mach-Zehnder modulators (MZMs), saving four MZ interferometers (MZIs). Furthermore, based on the asymmetric architecture, the FAR algorithm can recover signals from frequency aliasing caused by frequency offset (FO), even when half of the signal spectrum is aliased. This algorithm enables the asymmetric architecture to narrow down guard bands between subcarriers or even overlap the subcarriers, saving the receiver bandwidth at the aggregation/hub side. The performance of the asymmetric uplink DP-PAM4 transmission with the FAR algorithm is evaluated in both simualations and experiments. The effects of laser linewidths and IQ skew on the performance of the FAR algorithm are also analyzed. Simulation results show the algorithm can recover 16 Gbaud and 32 Gbaud signal from 8 GHz and 16 GHz aliasing, respectively. In the experiments with 10 km fiber transmissions, the FAR algorithm can recover 10 Gbaud signals from 5 GHz frequency aliasing, saving about 20.83% of the total receiver bandwidth in a 2-subcarrier system.

2.
J Magn Reson Imaging ; 54(1): 227-236, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33590929

RESUMO

BACKGROUND: O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation is an important prognostic factor for gliomas and is associated with tumor angiogenesis. Arteriolar cerebral blood volume (CBVa) obtained from inflow-based vascular-space-occupancy (iVASO) magnetic resonance imaging (MRI) is assumed to be an indicator of tumor microvasculature. Its preoperative predictive ability for MGMT promoter methylation remains unclear. PURPOSE: To investigate the role of iVASO-CBVa histogram features in determining MGMT promoter methylation status of grade II-IV gliomas. STUDY TYPE: Retrospective SUBJECTS: Forty-six patients consisting of 20 MGMT methylated and 26 unmethylated gliomas. FIELD STRENGTH/SEQUENCE: 3.0 T magnetic resonance images containing iVASO MRI, T1 -weighted image (T1 WI), T2 -weighted image, T2 -weighted fluid attenuated inversion recovery image images, and enhanced T1 WI. ASSESSMENT: Sixteen structural imaging features were visually evaluated on structural MRI and 14 CBVa histogram features were extracted from iVASO-CBVa maps. STATISTICAL TESTS: Imaging features were screened and ranked using Fisher's exact test, Mann-Whitney U-test, and randomforest algorithm. Features with higher importance were selected to develop logistic regression models to determine MGMT methylation status. Receiver operating characteristics (ROC) curve with the area under the curve (AUC) and leave-one-out cross-validation (LOOCV) were used to assess effectiveness and stability. RESULTS: The top two CBVa histogram features were root mean squared (RMS) and variance. The top two structural imaging features were contrast-enhancing component of the tumor (CET) location and tumor location. Both the CBVa model of RMS and variance (ROC, AUC = 0.867; LOOCV, AUC = 0.819) and the model of structural features (ROC, AUC = 0.882; LOOCV, AUC = 0.802) accurately identified MGMT methylation. The fusion model of CBVa RMS and CET location improved diagnostic performance (ROC, AUC = 0.931; LOOCV, AUC =0.906). DATA CONCLUSION: iVASO-CBVa has potential in evaluating MGMT methylation status in grade II-IV gliomas. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY: Stage 2.


Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioma/diagnóstico por imagem , Glioma/genética , Humanos , Imageamento por Ressonância Magnética , Metilação , O(6)-Metilguanina-DNA Metiltransferase , Estudos Retrospectivos , Organização Mundial da Saúde
3.
Adv Sci (Weinh) ; 7(4): 1901758, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32099755

RESUMO

Tens of thousands of metal-organic frameworks (MOFs) have been developed in the past two decades, and only ≈100 of them have been demonstrated as porous and hydrophobic. These hydrophobic MOFs feature not only a rich structural variety, highly crystalline frameworks, and uniform micropores, but also a low affinity toward water and superior hydrolytic stability, which make them promising adsorbents for diverse applications, including humid CO2 capture, alcohol/water separation, pollutant removal from air or water, substrate-selective catalysis, energy storage, anticorrosion, and self-cleaning. Herein, the recent research advancements in hydrophobic MOFs are presented. The existing techniques for qualitatively or quantitatively assessing the hydrophobicity of MOFs are first introduced. The reported experimental methods for the preparation of hydrophobic MOFs are then categorized. The concept that hydrophobic MOFs normally synthesized from predesigned organic ligands can also be prepared by the postsynthetic modification of the internal pore surface and/or external crystal surface of hydrophilic or less hydrophobic MOFs is highlighted. Finally, an overview of the recent studies on hydrophobic MOFs for various applications is provided and suggests the high versatility of this unique class of materials for practical use as either adsorbents or nanomaterials.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31661926

RESUMO

Job insecurity is a modifiable risk factor for poor health outcomes, and exposure to job insecurity varies by population groups. This study assessed if job insecurity exposure varied by migrant status and if the differences varied by gender, age, educational attainment, and occupational skill level. Data were from wave 14 of the Household Income and Labour Dynamics in Australia Survey. The outcome was job insecurity. Exposure was migrant status defined by (1) the country of birth (COB), (2) the dominant language of the COB, and (3) the number of years since arrival in Australia. Data were analysed using linear regression, adjusting for gender, age, educational attainment, and occupational skill level. These covariates were also analysed as effect modifiers for the migrant status-job insecurity relationships. Migrant workers, especially those from non-English speaking countries (non-ESC-born), experienced higher job insecurity than Australia-born workers; however, these disparities disappeared after 11+ years post-arrival. The migrant status-job insecurity relationships were modified by educational attainment. Unexpectedly, the disparities in job insecurity between non-ESC-born migrants and Australia-born workers increased with increasing educational attainment, and for those most highly educated, the disparities persisted beyond 11 years post-arrival. Our findings suggested that continuing language skill support and discrimination prevention could facilitate migrant integration into the Australian labour market.


Assuntos
Emprego/estatística & dados numéricos , Migrantes/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Austrália , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Ocupações , Fatores Sexuais , Fatores Socioeconômicos , Adulto Jovem
5.
Clin Rheumatol ; 37(3): 597-605, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29116543

RESUMO

The objective of this study is to evaluate the remission rate and describe the current use of medication in a large cohort of rheumatoid arthritis (RA) patients under routine clinical care in China. RA patients were recruited from 40 large teaching hospitals nationwide in China. Data regarding RA disease activity, medication treatment, and adverse events were recorded using a standardized clinical data questionnaire. RA remission was evaluated by the 28 Joint Disease Activity Score DAS28-ESR Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), and American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria. A total of 1945 patients with RA were included in the study. The proportions of patients who fulfilled the DAS28-ESR, CDAI, SDAI, and ACR/EULAR remission criteria were 10.90%, 6.17%, 5.04% , and 1.75%, respectively. Most patients had taken at least one disease-modifying anti-rheumatic drug (DMARD), and the most common prescriptions included leflunomide (LEF) and methotrexate (MTX). DMARD combined with botanics were the most common and dominant strategy for RA management (29.16%). Overall, 433 patients (22.27%) had at least one adverse event. Gastrointestinal adverse events (41.27%) were the most frequently reported events. The incidence of side effects in patients using biologics DMARDs (bDMARDs) was significantly lower than that in those taking MTX, LEF, or sulfasalazine (SSZ). The remission rate of RA disease activity, as assessed in Chinese clinical practice, was very low. Adverse effects of the medicine occurred in approximately one in five RA patients, with bDMARDs were demonstrated to be the medication with the lowest side effects.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Metotrexato/uso terapêutico , Indução de Remissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/diagnóstico , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
6.
Sci Rep ; 7: 46490, 2017 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-28429786

RESUMO

The sodium taurocholate cotransporting polypeptide (NTCP) encoded by SLC10A1 was recently demonstrated to be a functional receptor for hepatitis B virus (HBV). The role of SLC10A1 polymorphisms, particularly the Ser267Phe variant (rs2296651) in exon 4, has been frequently investigated in regard to risk of persistent HBV infection. However, these investigations have generated conflicting results. To examine whether common genetic variation at the SLC10A1 locus is associated with risk of persistent HBV infection, haplotype-tagging and imputed single nucleotide polymorphisms (SNPs) were assessed in two case-control sample sets, totally including 2,550 cases (persistently HBV infected subjects, PIs) and 2,124 controls (spontaneously recovered subjects, SRs) of Southern Chinese ancestry. To test whether rare or subpolymorphic SLC10A1 variants are associated with disease risk, the gene's exons in 244 cases were sequenced. Overall, we found neither SNPs nor haplotypes of SLC10A1 showed significant association in the two sample sets. Furthermore, no significant associations of rare variants or copy number variation covering SLC10A1 were observed. Finally, expression quantitative trait locus analyses revealed that SNPs potentially affecting SLC10A1 expression also showed no significant associations. We conclude that genetic variation at the SLC10A1 locus is not likely a major risk factor of persistent HBV infection among Southern Chinese.


Assuntos
Predisposição Genética para Doença , Vírus da Hepatite B , Hepatite B Crônica/genética , Desequilíbrio de Ligação , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , Polimorfismo de Nucleotídeo Único , Simportadores/genética , Adulto , Povo Asiático , China/epidemiologia , Feminino , Estudo de Associação Genômica Ampla , Hepatite B Crônica/epidemiologia , Humanos , Masculino , Fatores de Risco
7.
Arthritis Care Res (Hoboken) ; 66(4): 523-31, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24023001

RESUMO

OBJECTIVE: To estimate the annual direct and indirect costs of rheumatoid arthritis (RA) in China and identify the predictors for cost of illness. METHODS: A cross-sectional study of cost of illness from the societal perspective was conducted on 829 patients with RA in 21 tertiary care hospitals in China between July 2009 and December 2010. Data on demographics, clinical variables, and components of costs were collected by physician interview. Costs were represented in 2009 US dollars using purchasing power parity estimates. Univariate and multivariate linear regression analyses were performed to identify the predictors for cost of illness. RESULTS: The mean ± SD total cost of RA in China was $3,826 ± $5,659 per patient-year, given a gross domestic product per capita of $6,798 in China in 2009. Direct costs and indirect costs comprised 90.0% and 10.0% of the total costs, respectively. Drug expense represented approximately half of the total costs, dominated by biologic agents (48.2%) and disease-modifying antirheumatic drugs (23.5%). Additionally, the cost of extracted herbal drugs and traditional Chinese medicine comprised ∼17.6% of the drug expense. Higher education level, noninsured status, longer disease duration, more extraarticular manifestations, and higher Health Assessment Questionnaire score independently predicted higher total costs. CONCLUSION: Our results provide the first study of costs of RA in China. This study not only demonstrates the economic burden of RA, but also identifies the predictors that could be interventional factors to reduce the societal costs of RA in China.


Assuntos
Artrite Reumatoide/economia , Efeitos Psicossociais da Doença , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Centros de Atenção Terciária/estatística & dados numéricos
8.
Beijing Da Xue Xue Bao Yi Xue Ban ; 44(2): 182-7, 2012 Apr 18.
Artigo em Chinês | MEDLINE | ID: mdl-22516984

RESUMO

OBJECTIVE: To investigate the current status of tumor necrosis factor (TNF) inhibitors application in rheumatoid arthritis (RA) patients in China and to analyze the related factors. METHODS: A retrospective survey was conducted in 21 hospitals from different parts of China. The patients with RA were randomly enrolled. Data of their social backgrounds, clinical conditions, usage and adverse effects of TNF inhibitors were collected. The costs of TNF inhibitors and the indirect costs of the disease were calculated. A multivariate Logistic regression analysis was performed to analyze the factors related to TNF inhibitors application. RESULTS: In the study, 1 095 RA patients from July 2009 to November 2010 were enrolled, of whom 112 had received TNF inhibitors, representing 10.2% of the total patients. The patients who received etanercept and infliximab were 7.4% (86/1 095) of the patients and 2.4% (26/1 095), respectively. There were 0.5% of the patients (5/1 095) who had received both of the TNF inhibitors. The patients who had accepted etanercept and treatment duration for less than 3 months and 3-6 months accounted for 38.5% and 25.0% respectively, while those treated with Infliximab were 38.1%. Their health assessment questionnaire (HAQ) scores were 1.1, 0.5 and 0.1, corresponding to treatment duration of infliximab for less than 3, 3-6 and 6-9 months and those were 1.3, 1.0, 0.3 corresponding to treatment duration of etanercept, respectively. Infliximab costs were RMB 24 525.0, 69 300.0 and 96 800.0 Yuan and etanercept costs were RMB 7 394.8, 9 158.6, 54 910.9 Yuan, respectively. Indirect costs for RA patients who accepted infliximab for less than 3, 3-6 and 6-9 months were RMB 365.6, 0 and 158.9 Yuan and those who accepted etanercept were RMB 2 158.4, 288.5 and 180.1 Yuan, respectively. Allergy and infection were the main side-effects of etanercept and both happened in 3.5% of all the patients. Liver damage happened in 2.3% of all the patients, while allergy and infection happened in 6.5% of all the patients who accepted infliximab. Logistic regression analysis showed that patients with higher education experience increased the odds of entering the TNF inhibitors group (OR: 1.292, 95%CI: 1.132-1.473, P=0.000). CONCLUSION: About one-tenth of RA patients in China have accepted TNF inhibitors. Higher education experience is the key factor for using TNF inhibitors.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Honorários por Prescrição de Medicamentos/estatística & dados numéricos , Inibidores do Fator de Necrose Tumoral , Adulto , Idoso , Anti-Inflamatórios não Esteroides/economia , Anticorpos Monoclonais/economia , Anticorpos Monoclonais/uso terapêutico , Artrite Reumatoide/economia , China , Etanercepte , Feminino , Humanos , Imunoglobulina G/economia , Imunoglobulina G/uso terapêutico , Imunossupressores/economia , Imunossupressores/uso terapêutico , Infliximab , Masculino , Pessoa de Meia-Idade , Receptores do Fator de Necrose Tumoral/uso terapêutico , Estudos Retrospectivos , Inquéritos e Questionários
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