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1.
Risk Anal ; 44(1): 87-107, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36898960

RESUMO

Existing studies on the environmental Kuznets curve (EKC) neglect the inverse effect of pollution transfer from environmental regulation interactions on pollution reduction from a risk analysis perspective. Based on the regional differentiated attitudes on the environmental regulation reached in risk communication by the risk awareness biases of multiple interest groups, this article clarifies the causality between risk communication and risk transfer based on multistakeholder engagement processes; furthermore, the article incorporates the simultaneous action of the technological innovation effect and pollution risk transfer effect to construct a spatial environmental hyperbolic model with a bidirectional correlation between pollution emissions and economic growth in different regions. To verify our model, we select the pollution from agricultural watersheds in China as a sample to examine the two inverse effects. The results demonstrate that (1) agricultural watershed pollution and economic growth show an inverted U-shaped relation and a U-shaped relation in the local region and adjacent regions, respectively; (2) the pollution reduction assessment of the classical EKC model can be largely attributed to pollution risk transfer behavior; and (3) the turning point of the U-shaped curve appears earlier than that of the inverted U-shaped curve in the spatial hyperbola model. The findings suggest that stakeholders should consider the risk awareness bias caused by the imbalance of regional economic development and the scenarios that provide a "haven" for pollution risk transfer. Moreover, our study expands the theoretical connotation of the classical EKC hypothesis and is more suitable for pollution reduction scenarios in developing countries.

2.
J Am Chem Soc ; 145(16): 9254-9263, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37053465

RESUMO

Developing adsorbents with multiple merits in capacity, selectivity, mass transfer, and stability toward C2H2/CO2 separation is crucial and challenging for producing high-purity C2H2 for advanced polymers and the electronic industry. Here, we demonstrate a vertex strategy to create adsorbents combining these merits through rationally designing the vertex groups of a wavy-shaped framework in layered 2D metal-organic frameworks (MOFs) to finely regulate the local conformation and stacking interactions, which creates the optimal inter- and intralayer space to realize simultaneous improvement of adsorption thermodynamics and kinetics. Two new hydrolytically stable MOFs, ZUL-330 and ZUL-430, were prepared, and diverse experiments and modeling on both adsorption equilibrium and diffusion were performed. Record separation selectivities coupled with extraordinary dynamic C2H2 capacities were achieved for C2H2/CO2 mixtures with different proportions (50/50 or 10/5, v/v), along with a small diffusion barrier and fast mass transfer. Consequently, polymer-grade (99.9%) and electronic-grade (99.99%) C2H2 were obtained with excellent productivities of up to ∼6 mmol cm-3.

3.
Am J Epidemiol ; 192(10): 1637-1646, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37392093

RESUMO

We examined the associations between lung function and incident dementia and cognitive decline in 12,688 participants in the ARIC Study who provided lung function measurements in 1990-1992. Cognitive tests were administered up to 7 times, and dementia was ascertained through 2019. We used shared parameter models to jointly fit proportional hazard models and linear mixed-effect models to estimate lung-function-associated dementia rate and cognitive change, respectively. Higher forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were associated with reduced dementia (n = 2,452 persons developed dementia); hazard ratios per 1-L increase in FEV1 and FVC were 0.79 (95% confidence interval (CI): 0.71, 0.89) and 0.81 (95% CI: 0.74, 0.89), respectively. Each 1-L increase in FEV1 and FVC was associated with a 0.08-standard deviation (SD) (95% CI: 0.05, 0.12) and a 0.05-SD (95% CI: 0.02, 0.07) attenuation of 30-year cognitive decline, respectively. A 1% increase in FEV1/FVC ratio was associated with 0.008-SD (95% CI: 0.004, 0.012) less cognitive decline. We observed statistical interaction between FEV1 and FVC, suggesting that cognitive declines depended on values of specific FEV1 and FVC (as compared with FEV1, FVC, or FEV1/FVC ratio models that suggested linear incremental associations). Our findings may have important implications for reducing the burden of cognitive decline that is attributable to environmental exposures and associated lung function impairment.


Assuntos
Aterosclerose , Disfunção Cognitiva , Demência , Humanos , Pulmão , Volume Expiratório Forçado , Aterosclerose/epidemiologia , Disfunção Cognitiva/epidemiologia , Demência/epidemiologia , Demência/etiologia
4.
Curr Opin Nephrol Hypertens ; 32(1): 89-97, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36444667

RESUMO

PURPOSE OF REVIEW: Glomerular filtration rate (GFR) is the best index for kidney function and estimated GFR (eGFR) calculated from endogenous filtration markers like serum creatinine and cystatin C is widely used in clinical practice for chronic kidney disease diagnosis and prognostication. We sought to review the evolution of GFR estimating equations, nuances of eGFR interpretation, and utility of eGFR in drug dosing. RECENT FINDINGS: The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) serum creatinine eGFR equation was recently updated to exclude the race variable and the CKD-EPI creatinine-cystatin C equation demonstrated the highest reliability. Although calculated creatinine clearance by Cockcroft Gault has been traditionally used for drug dosing, the use of eGFR is slowly being adapted by the Food and Drug Administration for pharmacokinetic studies. However, the individual-level accuracy of eGFR using the CKD-EPI 2021 equations remained low, with the distribution of measured GFR at a given eGFR value spanning several CKD stages. SUMMARY: Although current methods of estimating GFR have improved in population measures of reliability, all have significant individual-level inaccuracies that can be an issue when clinical decision-making is contingent on the actual level of GFR. Modern methods of GFR measurements should be made widely available to enhance individualized patient decision-making.


Assuntos
Cistatina C , Insuficiência Renal Crônica , Estados Unidos , Humanos , Creatinina , Taxa de Filtração Glomerular , Reprodutibilidade dos Testes , Insuficiência Renal Crônica/diagnóstico
5.
Aging Clin Exp Res ; 35(1): 203-212, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36319940

RESUMO

BACKGROUND: The optimal number of examined lymph nodes (ELNs) for older early-stage pulmonary carcinoid tumour (PC) patients is unknown. AIMS: To explore the prognostic effect of the ELN count in older patients with stage T1N0M0 PC resection. METHODS: Clinical data from the Surveillance, Epidemiology, and End Results database on stage T1N0M0 PC older patients (age ≥ 65 years) who underwent sublobar resection and lobectomy between 2000 and 2018 were retrospectively analysed for two ELNs-stratified (≥ 7 vs. < 7 ELNs) propensity score-matched (PSM) groups. Overall survival (OS) was calculated and compared with Kaplan-Meier analysis and log-rank test, respectively, and the independent prognostic factors were estimated using a Cox proportional hazard model. RESULTS: Among 1077 participants (median dissected LN 4; mean ELNs 6.19 ± 7.04), 393 (36.49%) in the ≥ 7 ELNs group had better 5- and 10-year OS than the < 7 ELNs group (before PSM: 5-year OS = 93.01 vs. 85.22%, 10-year OS = 72.38 vs. 58.99%, p < 0.001; after PSM: 5-year OS = 93.12 vs. 85.97%, 10-year OS = 75.25 vs. 60.03%, p = 0.001). Subgroup analysis stratified by histologic type and surgical method showed a similar survival trend. Age-stratified analysis showed that, compared with the < 7 ELNs group, the ≥ 7 ELNs group had better 5- and 10-year OS but only better 5-year OS in participants > 75 years. Compared with the < 7 ELNs group, subgroup analysis by tumour size showed superior OS with 1.1-3.0 cm tumours in the ≥ 7 ELNs group, but no significant intergroup difference with tumours < 1.0 cm. Multivariate Cox analysis showed ≥ 7 ELNs was associated with improved OS. CONCLUSION: Higher ELNs correlated with increased long-term survival in older early­stage PC patients, and a minimum of 7 ELNs are recommended for prognostication in these patients (especially those aged 65-75 years, with tumour size 1.1-3.0 cm).


Assuntos
Tumor Carcinoide , Neoplasias Pulmonares , Humanos , Idoso , Prognóstico , Estudos Retrospectivos , Pontuação de Propensão , Estadiamento de Neoplasias , Linfonodos/patologia , Linfonodos/cirurgia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Tumor Carcinoide/cirurgia , Tumor Carcinoide/patologia
6.
Ann Intern Med ; 175(8): 1073-1082, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35785532

RESUMO

BACKGROUND: Although the population-level differences between estimated glomerular filtration rate (eGFR) and measured glomerular filtration rate (mGFR) are well recognized, the magnitude and potential clinical implications of individual-level differences are unknown. OBJECTIVE: To quantify the magnitude and consequences of the individual-level differences between mGFRs and eGFRs. DESIGN: Cross-sectional study. SETTING: Four U.S. community-based epidemiologic cohort studies with mGFR. PATIENTS: 3223 participants in 4 studies. MEASUREMENTS: The GFRs were measured using urinary iothalamate and plasma iohexol clearance; the eGFR was calculated from serum creatinine concentration alone (eGFRCR) and with cystatin C. All GFR results are presented as mL/min/1.73 m2. RESULTS: The participants' mean age was 59 years; 32% were Black, 55% were women, and the mean mGFR was 68. The population-level differences between mGFR and eGFRCR were small; the median difference (mGFR - eGFR) was -0.6 (95% CI, -1.2 to -0.2); however, the individual-level differences were large. At an eGFRCR of 60, 50% of mGFRs ranged from 52 to 67, 80% from 45 to 76, and 95% from 36 to 87. At an eGFRCR of 30, 50% of mGFRs ranged from 27 to 38, 80% from 23 to 44, and 95% from 17 to 54. Substantial disagreement in chronic kidney disease staging by mGFR and eGFRCR was present. Among those with eGFRCR of 45 to 59, 36% had mGFR greater than 60 whereas 20% had mGFR less than 45; among those with eGFRCR of 15 to 29, 30% had mGFR greater than 30 and 5% had mGFR less than 15. The eGFR based on cystatin C did not provide substantial improvement. LIMITATION: Single measurement of mGFR and serum markers without short-term replicates. CONCLUSION: A substantial individual-level discrepancy exists between the mGFR and the eGFR. Laboratories reporting eGFR should consider including the extent of this uncertainty to avoid misinterpretation of eGFR as an mGFR replacement. PRIMARY FUNDING SOURCE: National Institutes of Health.


Assuntos
Cistatina C , Insuficiência Renal Crônica , Creatinina , Estudos Transversais , Feminino , Taxa de Filtração Glomerular , Humanos , Testes de Função Renal/métodos , Masculino , Pessoa de Meia-Idade
7.
Alzheimers Dement ; 19(6): 2307-2316, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36462211

RESUMO

BACKGROUND: Hearing and vision impairments are risk factors for cognitive decline; less is known about dual sensory impairment. This study quantifies the association between dual sensory impairment and 8-year change in memory among older adults. METHODS: Data (N = 5552) were from the National Health and Aging Trends Study. Memory (immediate/delayed word recall, subjective memory) was measured annually (2011 to 2019). Hearing and vision impairments were measured by self-report. Association between dual sensory impairment and 8-year change in memory was assessed using multivariate linear mixed effect models and generalized logistic mixed models. RESULTS: Rate of memory decline was most accelerated among participants with dual sensory impairment. For example, 8-year decline in delayed word recall was -1.03 (95% confidene interval: -1.29, -0.77) for dual sensory impairment versus -0.79 (-0.92, -0.67) for single and -0.56 (-0.63, -0.48) for no impairment. CONCLUSION: Older adults with dual sensory impairment may be at particularly higher risk for cognitive decline.


Assuntos
Perda Auditiva , Vida Independente , Humanos , Idoso , Perda Auditiva/epidemiologia , Transtornos da Visão/epidemiologia , Transtornos da Visão/psicologia , Audição , Transtornos da Memória
8.
Nature ; 592(7855): 507, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33879887

Assuntos
China
9.
Hum Reprod ; 36(7): 2020-2034, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-33974705

RESUMO

STUDY QUESTION: What is the potential of applying non-invasive preimplantation genetic testing (niPGT) for chromosome abnormalities in blastocysts reported with a mosaic trophectoderm (TE) biopsy? SUMMARY ANSWER: niPGT of cell-free DNA in blastocyst culture medium exhibited a good diagnostic performance in putative mosaic blastocysts. WHAT IS KNOWN ALREADY: Advances in niPGT have demonstrated the potential reliability of cell-free DNA as a resource for genetic assessment, but information on mosaic embryos is scarce because the mosaicism may interfere with niPGT. In addition, the high incidence of mosaicism reported in the context of PGT and the viability of mosaic blastocysts raise questions about whether mosaicism really exists. STUDY DESIGN, SIZE, DURATION: The study was performed between May 2020 and July 2020. First, clinical data collected by a single-center over a 6-year period on PGT for chromosome aneuploidies (PGT-A) or chromosomal structural rearrangements (PGT-SR) were analyzed. After confirming the reliability of niPGT, 41 blastocysts classified as mosaics by trophectoderm (TE) biopsy were re-cultured. The chromosomal copy number of the blastocyst embryo (BE, the gold standard), TE re-biopsy, and corresponding cell-free DNA in the culture medium was assessed. PARTICIPANTS/MATERIALS, SETTING, METHODS: Data on patients enrolled for PGT at a single center from 2014 to 2019 were collected and the cycles with available putative mosaic blastocysts were evaluated. To verify the diagnostic validity of niPGT, eight aneuploid blastocysts were thawed and re-cultured for 14-18 h. The concordance of the niPGT diagnosis results and the whole blastocyst testing results was analyzed. Forty-one blastocysts reported as mosaics from 22 patients were included and re-cultured for 14-18 h. The genetic material of the BE, TE re-biopsy, and corresponding cell-free DNA in the culture medium was amplified using multiple annealing and looping-based amplification cycles. The karyotype data from niPGT and TE re-biopsy were compared with that from the whole blastocyst, and the efficiency of niPGT was assessed. MAIN RESULTS AND THE ROLE OF CHANCE: Data on 3738 blastocysts from 785 PGT-A or PGT-SR cycles of 677 patients were collected. According to the TE biopsy report, of the 3662 (98%) successfully amplified samples, 24 (0.6%) yielded no results, 849 (23.2%) were euploid, 2245 (61.3%) were aneuploid, and 544 (14.9%) were mosaic. Sixty patients without euploid blastocysts opted for a single mosaic blastocyst transfer, and 30 (50%) of them obtained a clinical pregnancy. With the BE chromosome copy number as the gold standard, niPGT and TE re-biopsy showed reliable detection ability and diagnostic efficiency in eight putative aneuploid blastocysts. Of the 41 putative mosaic blastocysts re-cultured and re-tested, 35 (85.4%) showed euploid BE results. All but two of the blastocysts previously diagnosed with segmental chromosomal mosaic were actually euploid. In addition, all blastocysts previously classified as low degree (20-50%) mosaics were identified as euploid by BE PGT, whereas four of the six putative high degree (50-80%) mosaic blastocysts showed chromosomal abnormalities. The raw concordance rates of spent culture medium (SCM) and TE re-biopsies compared with BE were 74.4% and 82%, respectively, in terms of overall ploidy and 96.2% and 97.6%, respectively, per single chromosome when considering all degree mosaic results as true positives. However, when we set a mosaicism identification threshold of 50%, the concordance rates of SCM and TE re-biopsies compared with BE were 87.2% and 85% at the overall ploidy level and 98.8% and 98.3% at the chromosomal level, respectively. At the full ploidy level, the sensitivity and false negative rates for niPGT were 100% and 0, respectively. After adjustment of the threshold for mosaicism, the specificity of niPGT increased from 69.7% to 84.8% in terms of overall ploidy and from 96.1% to 98.9% at the chromosomal level. LIMITATIONS, REASONS FOR CAUTION: The primary limitation of this study is the small sample size, which decreases the strength of our conclusions. If possible, identifying the clinical outcome of niPGT on reassessed mosaic blastocysts would be further progress in this field. WIDER IMPLICATIONS OF THE FINDINGS: This study is the first to explore the practicability of niPGT in diagnostic reassessment of putative mosaicism. The present study provides a novel opportunity for patients with only mosaic blastocysts and no euploid blastocysts, regardless of the technical or biological basis of mosaicism. Employing niPGT after 14-18 h of re-culturing might be a superior option for the best use of blastocysts because of its minimally invasive nature. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from National Key Technology Research and Development Program of China (No. 2017YFC1002004), the Central Guiding the Science and Technology Development of the Local (2018080802D0081) and College Natural Science Project of Anhui Province (KJ2019A0287). There are no competing interests to declare. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Diagnóstico Pré-Implantação , Aneuploidia , Blastocisto , China , Feminino , Testes Genéticos , Humanos , Projetos Piloto , Gravidez , Reprodutibilidade dos Testes
10.
Entropy (Basel) ; 23(9)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34573852

RESUMO

The accuracy and efficiency of sound field calculations highly concern issues of hydroacoustics. Recently, one-dimensional spectral methods have shown high-precision characteristics when solving the sound field but can solve only simplified models of underwater acoustic propagation, thus their application range is small. Therefore, it is necessary to directly calculate the two-dimensional Helmholtz equation of ocean acoustic propagation. Here, we use the Chebyshev-Galerkin and Chebyshev collocation methods to solve the two-dimensional Helmholtz model equation. Then, the Chebyshev collocation method is used to model ocean acoustic propagation because, unlike the Galerkin method, the collocation method does not need stringent boundary conditions. Compared with the mature Kraken program, the Chebyshev collocation method exhibits a higher numerical accuracy. However, the shortcoming of the collocation method is that the computational efficiency cannot satisfy the requirements of real-time applications due to the large number of calculations. Then, we implemented the parallel code of the collocation method, which could effectively improve calculation effectiveness.

12.
J Assist Reprod Genet ; 37(3): 497-508, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31838629

RESUMO

Embryos containing distinct cell lines are referred to as mosaic embryos, which are considered to be caused by mitotic errors in chromosome segregation during preimplantation development. As the accuracy and resolution of detection techniques improve, more and more mosaic embryos were identified recently. The impacts of mosaic embryos on survival and potential pregnancy outcome have been reported to be diverse in different studies. Because of the universality and clinical significance of mosaicism, it is essential to unravel the mechanisms and consequences with regard to this phenomenon in human pre- and post-implantation embryos. The purpose of this review is to explore the mechanisms, causes of mosaicism, and the development of pre- and post-implantation mosaic embryos in the light of recent emerging data, with the aim of providing new references for clinical applications.


Assuntos
Blastocisto , Segregação de Cromossomos/genética , Desenvolvimento Embrionário/genética , Mosaicismo/embriologia , Implantação do Embrião/genética , Feminino , Testes Genéticos , Humanos , Gravidez , Resultado da Gravidez , Diagnóstico Pré-Implantação , Técnicas de Reprodução Assistida/tendências
13.
Entropy (Basel) ; 22(9)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33286683

RESUMO

In this paper, a novel signal detector based on matrix information geometric dimensionality reduction (DR) is proposed, which is inspired from spectrogram processing. By short time Fourier transform (STFT), the received data are represented as a 2-D high-precision spectrogram, from which we can well judge whether the signal exists. Previous similar studies extracted insufficient information from these spectrograms, resulting in unsatisfactory detection performance especially for complex signal detection task at low signal-noise-ratio (SNR). To this end, we use a global descriptor to extract abundant features, then exploit the advantages of matrix information geometry technique by constructing the high-dimensional features as symmetric positive definite (SPD) matrices. In this case, our task for signal detection becomes a binary classification problem lying on an SPD manifold. Promoting the discrimination of heterogeneous samples through information geometric DR technique that is dedicated to SPD manifold, our proposed detector achieves satisfactory signal detection performance in low SNR cases using the K distribution simulation and the real-life sea clutter data, which can be widely used in the field of signal detection.

14.
Macromol Rapid Commun ; 40(1): e1800660, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30350437

RESUMO

Nonfullerene polymer solar cells (PSCs) are developed based on a fluorinated thienyl-based wide-bandgap (WBG) polymer PBBF as the electron donor and nonfullerene small molecule IDIC as the electron acceptor. PBBF exhibits a strong absorption in the range of 300-605 nm with a wide optical bandgap of 2.05 eV, which is complementary with that of IDIC. Meanwhile, it possesses a deeper highest occupied molecular orbital energy level of  -5.52 eV and a higher hole mobility of 7.3 × 10-4  cm2 V-1  s-1 compared to the nonfluorinated polymer PBDTT. The PSCs based on PBBF:IDIC without extra treatment show a power conversion efficiency (PCE) of 8.5% with a V oc of 0.95 V, a J sc of 15.3 mA cm-2 , and an FF of 58.8%, which is much higher than that of the devices based on PBDTT:IDIC (a PCE of 5.3% with a V oc of 0.88 V, a J sc of 13.7 mA cm-2 , and an FF of 43.9%). These results indicate that PBBF is a promising WBG polymer donor material for the photovoltaic applications in nonfullerene PSCs.


Assuntos
Fontes de Energia Elétrica , Fulerenos/química , Polímeros/química , Energia Solar
15.
J Org Chem ; 82(4): 2205-2210, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28103439

RESUMO

A tandem Michael-Henry reaction of 2-mercaptoquinoline-3-carbaldehydes with nitroolefins using hydrogen-bonding-based cooperative organocatalysts for the highly diastereodivergent synthesis of chiral functionalized 3,4-dihydro-2H-thiopyrano[2,3-b]quinolines with three contiguous tertiary stereocenters has been developed.

16.
BMC Bioinformatics ; 16 Suppl 7: S10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25952019

RESUMO

BACKGROUND: Short-read aligners have recently gained a lot of speed by exploiting the massive parallelism of GPU. An uprising alterative to GPU is Intel MIC; supercomputers like Tianhe-2, currently top of TOP500, is built with 48,000 MIC boards to offer ~55 PFLOPS. The CPU-like architecture of MIC allows CPU-based software to be parallelized easily; however, the performance is often inferior to GPU counterparts as an MIC card contains only ~60 cores (while a GPU card typically has over a thousand cores). RESULTS: To better utilize MIC-enabled computers for NGS data analysis, we developed a new short-read aligner MICA that is optimized in view of MIC's limitation and the extra parallelism inside each MIC core. By utilizing the 512-bit vector units in the MIC and implementing a new seeding strategy, experiments on aligning 150 bp paired-end reads show that MICA using one MIC card is 4.9 times faster than BWA-MEM (using 6 cores of a top-end CPU), and slightly faster than SOAP3-dp (using a GPU). Furthermore, MICA's simplicity allows very efficient scale-up when multiple MIC cards are used in a node (3 cards give a 14.1-fold speedup over BWA-MEM). SUMMARY: MICA can be readily used by MIC-enabled supercomputers for production purpose. We have tested MICA on Tianhe-2 with 90 WGS samples (17.47 Tera-bases), which can be aligned in an hour using 400 nodes. MICA has impressive performance even though MIC is only in its initial stage of development. AVAILABILITY AND IMPLEMENTATION: MICA's source code is freely available at http://sourceforge.net/projects/mica-aligner under GPL v3. SUPPLEMENTARY INFORMATION: Supplementary information is available as "Additional File 1". Datasets are available at www.bio8.cs.hku.hk/dataset/mica.


Assuntos
Biologia Computacional/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Alinhamento de Sequência/métodos , Análise de Sequência de DNA/métodos , Software , Algoritmos , Humanos , Linguagens de Programação
17.
J Ultrasound Med ; 33(9): 1669-75, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25154951

RESUMO

OBJECTIVES: The aim of this study was to explore the risk factors associated with failed sonographically guided saline hydrostatic intussusception reduction in children. METHODS: We retrospectively reviewed the medical records and sonograms of 288 cases of intussusception over a 3-year period. Logistic regression was used for the analysis of the clinical data (sex, age, duration of symptoms, and presence or absence of emesis or bloody stool) and sonographic features (initial location and intussusception length, presence or absence of free peritoneal fluid, and trapped fluid in the intussusception). RESULTS: The sex, age, and duration of symptoms showed no significant impact on the hydrostatic reducibility. The success rate became significantly lower for the intussusception cases with the presence of bloody stool, free peritoneal fluid, and trapped fluid in the intussusception (P < .05). The success rate was also lower when the intussusceptions were located in the left side of the abdomen (P < .05). For the above risk factors, the odds ratios from multivariate logistic regression analysis were 174.68 for initial intussusception location in the descending colon/rectum, 36.06 for the presence of peritoneal fluid, 13.22 for trapped fluid in the intussusception, and 9.27 for the presence of bloody stool. CONCLUSIONS: An initial intussusception location in the descending colon/rectum, the presence of peritoneal fluid, trapped fluid in the intussusception, and bloody stool are the most important risk factors for failure of sonographically guided saline hydrostatic intussusception reduction.


Assuntos
Intussuscepção/diagnóstico por imagem , Intussuscepção/terapia , Cloreto de Sódio/uso terapêutico , Ultrassonografia de Intervenção , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Intestinos/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
18.
ScientificWorldJournal ; 2014: 582042, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25215324

RESUMO

The satellite fault diagnosis has an important role in enhancing the safety, reliability, and availability of the satellite system. However, the problem of enormous parameters and multiple faults makes a challenge to the satellite fault diagnosis. The interactions between parameters and misclassifications from multiple faults will increase the false alarm rate and the false negative rate. On the other hand, for each satellite fault, there is not enough fault data for training. To most of the classification algorithms, it will degrade the performance of model. In this paper, we proposed an improving SVM based on a hybrid voting mechanism (HVM-SVM) to deal with the problem of enormous parameters, multiple faults, and small samples. Many experimental results show that the accuracy of fault diagnosis using HVM-SVM is improved.


Assuntos
Algoritmos , Modelos Teóricos , Comunicações Via Satélite/instrumentação , Máquina de Vetores de Suporte
19.
J Alzheimers Dis ; 100(1): 297-308, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38848187

RESUMO

Background: Brain imaging studies may provide etiologic insight into observed links between lung function and dementia and stroke. Objective: We evaluated associations of lung function measures with brain MRI markers of vascular and neurodegenerative disease in the ARIC Neurocognitive Study, as few studies have examined the associations. Methods: Lung function was measured at participants' midlife in 1990-1992 (mean age = 56±5 years) and later-life in 2011-2013 (mean age = 76±5 years), and brain MRI was performed in 2011-2013. Linear regression models were used to examine the associations of lung function with brain and white matter hyperintensity (WMH) volumes, and logistic regression models were used for cerebral infarcts and microbleeds, adjusting for potential confounders. Results: In cross-sectional analysis (i.e., examining later-life lung function and MRI markers, n = 1,223), higher forced-expiratory volume in one second (FEV1) and forced vital capacity (FVC) were associated with larger brain and lower WMH volumes [e.g., 8.62 (95% CI:2.54-14.71) cm3 greater total brain volume per one-liter higher FEV1]. No association was seen with microbleeds in the overall sample, but higher FVC was associated with lower odds of microbleeds in never-smokers and higher odds in ever-smokers. In the cross-temporal analysis (i.e., associations with midlife lung function, n = 1,787), higher FVC levels were significantly associated with lower later-life brain volumes. Conclusions: Our results support modest associations of better lung function with less neurodegenerative and cerebrovascular pathology, although findings for microbleeds were unexpected in ever-smokers.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estudos Transversais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Aterosclerose/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Pulmão/patologia , Testes de Função Respiratória , Capacidade Vital , Idoso de 80 Anos ou mais
20.
J Am Heart Assoc ; 13(6): e032008, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38456405

RESUMO

BACKGROUND: Sudden cardiac death (SCD) is a significant global public health problem accounting for 15% to 20% of all deaths. A great majority of SCD is associated with coronary heart disease, which may first be detected at autopsy. The ankle-brachial index (ABI) is a simple, noninvasive measure of subclinical atherosclerosis. The purpose of this study was to examine the relationship between ABI and SCD in a middle-aged biracial general population. METHODS AND RESULTS: Participants of the ARIC (Atherosclerosis Risk in Communities) study with an ABI measurement between 1987 and 1989 were included. ABI was categorized as low (≤0.90), borderline (0.90-1.00), normal (1.00-1.40), and noncompressible (>1.40). SCD was defined as a sudden pulseless condition presumed to be caused by a ventricular tachyarrhythmia in a previously stable individual and was adjudicated by a committee of cardiac electrophysiologists, cardiologists, and internists. Cox proportional hazards models were used to evaluate the associations between baseline ABI and incident SCD. Of the 15 081 participants followed for a median of 23.5 years, 556 (3.7%) developed SCD (1.96 cases per 1000 person-years). Low and borderline ABIs were associated with an increased risk of SCD (demographically adjusted hazard ratios [HRs], 2.27 [95% CI, 1.64-3.14] and 1.52 [95% CI, 1.17-1.96], respectively) compared with normal ABI. The association between low ABI and SCD remained significant after adjustment for traditional cardiovascular risk factors (HR, 1.63 [95% CI, 1.15-2.32]). CONCLUSIONS: Low ABI is independently associated with an increased risk of SCD in a middle-aged biracial general population. ABI could be incorporated into future SCD risk prediction models.


Assuntos
Aterosclerose , Doença das Coronárias , Pessoa de Meia-Idade , Humanos , Índice Tornozelo-Braço , Fatores de Risco , Aterosclerose/epidemiologia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Doença das Coronárias/complicações , Medição de Risco
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