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1.
Chin Med J (Engl) ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38663857

RESUMEN

BACKGROUND: Congenital heart disease (CHD) is a leading cause of birth defect-related mortality. However, more recent CHD mortality data for China are lacking. Additionally, limited studies have evaluated sex, rural-urban, and region-specific disparities of CHD mortality in China. METHODS: We designed a population-based study using data from the Dataset of National Mortality Surveillance in China between 2008 and 2021. We calculated age-adjusted CHD mortality using the sixth census data of China in 2010 as the standard population. We assessed the temporal trends in CHD mortality by age, sex, area, and region from 2008 to 2021 using the joinpoint regression model. RESULTS: From 2008 to 2021, 33,534 deaths were attributed to CHD. The period witnessed a two-fold decrease in the age-adjusted CHD mortality from 1.61 to 0.76 per 100,000 persons (average annual percent change [AAPC] = -5.90%). Females tended to have lower age-adjusted CHD mortality than males, but with a similar decline rate from 2008 to 2021 (females: AAPC = -6.15%; males: AAPC = -5.84%). Similar AAPC values were observed among people living in urban (AAPC = -6.64%) and rural (AAPC = -6.12%) areas. Eastern regions experienced a more pronounced decrease in the age-adjusted CHD mortality (AAPC = -7.86%) than central (AAPC = -5.83%) and western regions (AAPC = -3.71%) between 2008 and 2021. Approximately half of the deaths (46.19%) due to CHD occurred during infancy. The CHD mortality rates in 2021 were lower than those in 2008 for people aged 0-39 years, with the largest decrease observed among children aged 1-4 years (AAPC = -8.26%), followed by infants (AAPC = -7.01%). CONCLUSIONS: CHD mortality in China has dramatically decreased from 2008 to 2021. The slower decrease in CHD mortality in the central and western regions than in the eastern regions suggested that public health policymakers should pay more attention to health resources and health education for central and western regions.

2.
Phys Chem Chem Phys ; 26(1): 421-429, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-38078535

RESUMEN

Lattice thermal conductivity (κL) plays a crucial role in the thermal management of electronic devices. In this study, we systematically investigate the thermal transport properties of monolayer fluorinated graphene using a combination of machine learning-based interatomic potentials and the phonon Boltzmann transport equation. At a temperature of 300 K, we find that the κL values for chair-configured fluorinated graphene monolayers are 184.24 W m-1 K-1 in the zigzag direction and 205.57 W m-1 K-1 in the armchair direction. For the boat configuration, the κL values are 120.45 W m-1 K-1 and 64.26 W m-1 K-1 in the respective directions. The disparities in κL between these two configurations predominantly stem from differences in phonon relaxation times, which can be elucidated by examining the Grüneisen parameters representing the degree of anharmonicity. A more in-depth analysis of bond strengths, as assessed by the crystal orbital Hamiltonian population, reveals that the stronger in-plane CC bonds in chair-configured fluorinated graphene monolayers are the primary contributors to the observed variations in anharmonicity.

3.
Phys Chem Chem Phys ; 25(28): 19082-19090, 2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37427572

RESUMEN

By using density functional theory calculations combined with the nonequilibrium Green's function method and machine learning, we systematically studied the thermoelectric properties of four kinds of porous graphene nanosheets (PGNS) before and after nitrogen doping. The results show that the thermoelectric performance of porous graphene nanosheets along the armchair or zigzag chiral direction is improved due to the dramatically enhanced power factor caused by nitrogen doping. The calculated ZT values of nitrogen-doped porous graphene nanosheets are boosted by about one order of magnitude compared with those of undoped porous graphene nanosheets at room temperature. More importantly, an anisotropic thermoelectric transport is found in the nitrogen-doped porous graphene nanosheets. The results show that the ZT values of nitrogen-doped porous graphene nanosheets along the zigzag transport direction are nearly 11 times larger than those of them along the armchair transport direction. These results reveal that the thermoelectric properties of porous graphene nanosheets can be well regulated by nitrogen doping, and provide a good theoretical guidance for their application in thermoelectric devices.

4.
Lancet Reg Health West Pac ; 33: 100688, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37181527

RESUMEN

Background: Newborn Screening Programme for Congenital Heart Disease (CHD) in Shanghai has been in operation for over 5 years, and its feasibility and effectiveness still lack a systematic and comprehensive evaluation. This study aimed to detail the implementation of the programme and evaluate its results, benefits, and reliability in clinical practice. Methods: This study was an observational study involving all newborns received CHD screening in Shanghai from 2017 to 2021. Pulse oximetry (POX) plus cardiac murmur auscultation (namely the dual-index method) was used for CHD screening in newborns aged 6-72 h. Newborns who screened positive was recommended for echocardiography, and those diagnosed with CHD would be planned for further evaluation and intervention. Data were aggregated by birth year and district of birth. Results of neonatal CHD screening, diagnosis and treatment, and temporal trends of infant mortality rate (IMR) and the proportion of under-five mortality (U5M) attributed to CHD were analysed. A retrospective cohort study was also conducted to assess the reliability of the dual-index method in clinical practice. Findings: In total, 801,831 (99.48%) newborns were screened for CHD, 16,489 (2.06%) were screened positive, and 3541 (21.47%) of the screened-positive newborns were identified with CHD. Seven hundred and fifty-two patients with CHD received surgical or interventional treatment with a successful rate of 94.81%. The period from 2015 to 2021 witnessed an approximately twofold decrease in IMR from 4.58‰ to 2.30‰, and a downtrend in the proportion of U5M attributed to CHD from 25.93% to 16.61%. High sensitivity and specificity of the dual-index method in clinical practice were observed for both critical (100.00% and 97.72%) and major CHD (98.47% and 97.76%). Interpretation: Newborn screening programme for CHD has been well implemented in Shanghai, and this programme is a successful public health intervention to reduce infant death. Our study provides encouraging evidence and experience for implementing newborn screening programme for CHD nationwide in China. Funding: This study was supported by the National Key Research and Development Programme of China (2021YFC2701004 and 2016YFC1000506), CAMS Innovation Fund for Medical Sciences (2019-I2M-5-002), and Three-Year Planning for Strengthening the Construction of Public Health System in Shanghai (No. GWIV-24).

5.
J Phys Condens Matter ; 35(7)2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36541472

RESUMEN

The rapid development of synthesis and fabrication techniques has opened up a research upsurge in two-dimensional (2D) material heterostructures, which have received extensive attention due to their superior physical and chemical properties. Currently, thermoelectric energy conversion is an effective means to deal with the energy crisis and increasingly serious environmental pollution. Therefore, an in-depth understanding of thermoelectric transport properties in 2D heterostructures is crucial for the development of micro-nano energy devices. In this review, the recent progress of 2D heterostructures for thermoelectric applications is summarized in detail. Firstly, we systematically introduce diverse theoretical simulations and experimental measurements of the thermoelectric properties of 2D heterostructures. Then, the thermoelectric applications and performance regulation of several common 2D materials, as well as in-plane heterostructures and van der Waals heterostructures, are also discussed. Finally, the challenges of improving the thermoelectric performance of 2D heterostructures materials are summarized, and related prospects are described.

7.
J Phys Condens Matter ; 34(28)2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-35477168

RESUMEN

The design and control of spintronic devices is a research hotspot in the field of electronics, and pure carbon-based materials provide new opportunities for the construction of electronic devices with excellent performance. Using density functional theory in combination with nonequilibrium Green's functions method, we design spin filter devices based on Penta-hexa-graphene (PHG) nanoribbons-a carbon nanomaterial in which the intrinsic magnetic moments combines with edge effects leading to a half-metallic property. Spin-resolved electronic transport studies show that such carbon-based devices can achieve nearly 100% spin filtering effect at low bias voltages. Such SEF can resist the influence of hydrogen passivation at different positions, but hardly survive under a hydrogen-rich environment. Our analysis show that the perfect SEF transport properties are caused by the magnetic and electronic properties of PHG nanoribbons, especially the magnetic moments on the quasi-sp3carbons. These interesting results indicate that PHG nanomaterials have very prominent application prospects in future spintronic devices.

8.
Chem Biol Interact ; 331: 109233, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32991863

RESUMEN

Cisplatin (cis-Dichlorodiammine platinum, CP), as the first-line chemotherapy drug of choice for many cancers such as urogenital system tumors and digestive tract tumors, also causes toxicity and side effects to the kidney. Previous studies have shown that Pulsatilla chinensis has significant anti-inflammatory and antioxidant activities, but the mechanism of cisplatin induced acute kidney injury (AKI) in vivo has not been thoroughly studied. The purpose of this study is to investigate the protective effect of pulchinenoside B4 (PB4), a representative and major component with a content of up to 10% in root of P. chinensis, on AKI induced by CP in mice. Our results indicated the significant protective effect of PB4 by evaluating renal function indicators, inflammatory factor levels and renal histopathological changes. In addition, PB4 may mainly act on NF-κB signaling pathway to reduce the levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1ß), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in the kidney after CP exposure, thus exerting anti-inflammatory activity. Furthermore, PB4 regulated MAPK signaling pathway and its downstream apoptotic factors to inhibit the occurrence of apoptosis, such as Bax, Bcl-2, caspase 3 and caspase 9. Notably, the activations of caspase 3 induced by cisplatin were strikingly reduced in PB4-treated mice. Therefore, the above evidence suggested that PB4 is a potential renal protectant with significant anti-inflammatory and anti-apoptotic effects.


Asunto(s)
Lesión Renal Aguda/patología , Apoptosis/efectos de los fármacos , Sustancias Protectoras/farmacología , Transducción de Señal/efectos de los fármacos , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/veterinaria , Animales , Cisplatino/toxicidad , Modelos Animales de Enfermedad , Interleucina-1beta/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Masculino , Ratones , Ratones Endogámicos ICR , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Fosforilación , Sustancias Protectoras/química , Factor de Necrosis Tumoral alfa/metabolismo
9.
J Phys Condens Matter ; 32(30): 305301, 2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32197262

RESUMEN

New classes of two-dimensional (2D) materials beyond graphene are now attracting intense interest owing to their unique properties and functions. By combining first-principle calculation and the Boltzmann transport equation, we investigated the thermal transport properties of monolayer honeycomb structures of group-IV (C, Si, Ge, Sn) binary compounds. It is found that the thermal conductivity (κ) of these compounds span an enormously large range from 0.04 to 144.29 W m-1 K-1, demonstrating promising applications to nanoscale thermoelectrics and thermal management. The κ of low-buckled structures such as SiGe, SiSn and GeSn is lower than that of planar structures such as SiC, GeC and SnC, which can be ascribed to heavy atomic mass and broken in-plane reflection symmetry. Moreover, the κ of planar or low-buckled compounds with Sn atom is much lower than others, and the detailed origin for this phenomenon and contribution of different phonon modes to the κ are investigated. This work has fully studied the diversity of the thermal phenomenon and provides more options for application on thermal transport.

10.
J Phys Condens Matter ; 32(5): 055302, 2020 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-31600739

RESUMEN

Herein, thermoelectric properties of MoS2/MoSe2 lateral and van der Waals heterostructure are investigated by using density functional theory calculations and non-equilibrium Green's function method. Compared with pure MoS2, the thermoelectric performance of MoS2/MoSe2 lateral heterostructure is significantly improved due to the sharply decreased thermal conductance and slightly reduced power factor. Moreover, the thermoelectric performance can be further improved by constructing MoS2/MoSe2 van der Waals heterostructure. The room temperature ZT can reach 3.5, which is about 3 and 6 times greater than MoS2/MoSe2 lateral heterostructure and pure MoS2, respectively. This is because the strongly local electron and phonon states result in an ultralow thermal conductance in MoS2/MoSe2 van der Waals heterostructure. Furthermore, we also find that the thermoelectric performance of MoS2/MoSe2 van der Waals heterostructure is insensitive to contact areas due to the competing influence of PF and total thermal conductance. The current study presents an effective strategy to improve the thermoelectric performance of 2D heterostructures, which can be extended to a variety of materials for different applications.

11.
J Phys Condens Matter ; 30(27): 275701, 2018 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-29799436

RESUMEN

Inspired by the novel mechanism of reducing thermal conductivity by local phonon resonance instead of by inducing structural defects, we investigate the effect of side branching on the thermoelectric properties of [Formula: see text] nanoribbons, and prove that side branching is a highly efficient mechanism for enhancing the thermoelectricity of different kinds of nanoribbons. For both armchair and zigzag [Formula: see text] nanoribbons, the side branches result in not only significant blocking of phonon transport but also notable increase of the Seebeck coefficient. Consequently, the thermoelectric figure of merit of the armchair [Formula: see text] nanoribbon is boosted from 0.72 to as high as 1.93, and the originally non-thermoelectric metallic zigzag [Formula: see text] nanoribbon is turned into a thermoelectric material due to the appearance of the band gap induced by the side branches. These results mean that the mechanism of branching is not only very efficient, but also takes effect regardless of the original properties of the nanoribbons, and thus will hold great promise for its application in the thermoelectric field.

13.
World J Pediatr ; 10(4): 360-4, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25515808

RESUMEN

BACKGROUND: To investigate the clinical characteristics and analyze risk factors for severe respiratory syncytial virus (RSV) infection in hospitalized infants with acute lower respiratory tract infections (ALRIs). METHODS: A retrospective review of the medical records of infants with RSV-associated ALRIs between March 1st, 2011 and February 29th, 2012 was conducted. Subjects were followed up over the phone or by outpatient visit six and twelve months after discharge. RESULTS: Among 913 RSV-associated ALRIs infants, 288 (31.5%) had severe infections, which accounted for 4.2% of hospitalized children. The hospital RSV mortality rate was 1.0%. The proportions of cases with tachypnea, apnea, cyanosis, and fine rales were significantly higher in the severe ALRIs group (all P<0.001). Multivariate logistic regression showed that low-birth-weight [1.698 (1.028-2.805)], age less than 3 months old [3.385 (2.174-5.271)], congenital heart disease [1.667 (1.149-2.418)], bronchopulmonary dysplasia [8.505 (1.731-41.780)], and airway abnormalities [2.246 (1.008-5.005)] were independent risk factors for severe ALRIs. The incidence of bronchitis, pneumonia and readmission in the severe group was significantly higher than that of the non-severe group during the one-year follow-up (all P<0.001). CONCLUSIONS: Younger age, low birth weight and underlying disease are associated with severe RSVassociated ALRIs. Furthermore, severe RSV infections may be associated with a higher frequency of subsequent bronchitis, pneumonia and re-hospitalization in the following year.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio/epidemiología , Enfermedad Aguda , Niño Hospitalizado , China/epidemiología , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena de la Polimerasa/métodos , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad
14.
Zhonghua Er Ke Za Zhi ; 52(5): 373-7, 2014 May.
Artículo en Chino | MEDLINE | ID: mdl-24969937

RESUMEN

OBJECTIVE: To investigate the clinical epidemiologic characteristics and analyze risk factors for acute respiratory syncytial virus (RSV) infection in hospitalized infants with acute lower respiratory tract infection (ALRI). METHOD: ALRI infants admitted to Children's Hospital of Fudan University from March 1st, 2011 to February 29th, 2012, were enrolled in this study. Patient information included demographic characteristics, feeding history, family status, clinical presentation, accessory examination, treatment and prognosis. According to the etiology of ALRI infants, we compared the seasonal distribution, demographic characteristics, household characteristics and underlying diseases between RSV-positive patients and RSV-negative patients. Univariate and multiple Logistic regression analyses were used to determine factors that were associated with risk of RSV infection. RESULT: Among 1 726 ALRI infants, there were 913 RSV-positive infants (52.9%). The occurrence of RSV infection had a seasonal variation, with a peak in winter (59.1%). The median (P25, P75) age of RSV infants was 64 (21-155) days. The gestational age (GA) and body weight (BW) was (37.5 ± 2.4) weeks and (3.07 ± 0.66) kg, respectively. The male/female ratio among these was 1.9: 1. RSV infection was more popular among infants in the families with smoking members, crowded living conditions, history of atopic mother. Differences of the proportion of patients with underlying disease between RSV-positive and negative groups were statistically significant (59.4% vs. 54.2%, P < 0.05). Univariate logistic regression demonstrated that factors increasing the risk of RSV infection were: GA<37 weeks (OR = 1.346, 95%CI: 1.037-1.748), birth weight <2 500 g (OR = 1.447, 95%CI: 1.103-1.898), underlying diseases (OR = 1.232, 95%CI: 1.018-1.492), underlying CHD (OR = 1.391, 95%CI: 1.120-1.728), environmental tobacco smoke exposure (OR = 1.254, 95%CI: 1.035-1.519), mother with atopic diseases (OR = 1.827, 95%CI: 1.296-2.573), crowded house with four or more than four family members (OR = 1.232, 95%CI: 1.013-1.498), autumn or winter infection (OR = 1.351, 95%CI: 1.024-1.783; OR = 1.713, 95%CI: 1.332-2.204). Multivariate logistic regression determined the factors increasing the risk of RSV infection were: underlying CHD (OR = 1.298, 95%CI: 1.002-1.681), mother with atopic diseases (OR = 1.766, 95%CI: 1.237-2.520), autumn or winter infection (OR = 1.481, 95%CI: 1.105-1.985; OR = 1.766, 95%CI: 1.358-2.296). CONCLUSION: The prevalence of RSV infection was the highest in winter, while preterm and low birth weight infants were more susceptible. Underlying diseases were found in 59.4% cases, CHD was the most common one. The factors increasing the risk of RSV infection were: CHD, mother with atopic diseases, autumn or winter infections.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Hospitalización/estadística & datos numéricos , Infecciones por Virus Sincitial Respiratorio/epidemiología , Virus Sincitial Respiratorio Humano/aislamiento & purificación , Infecciones del Sistema Respiratorio/epidemiología , Enfermedad Aguda , China/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Prevalencia , Infecciones por Virus Sincitial Respiratorio/prevención & control , Infecciones del Sistema Respiratorio/prevención & control , Infecciones del Sistema Respiratorio/virología , Estudios Retrospectivos , Factores de Riesgo , Estaciones del Año , Factores Socioeconómicos , Contaminación por Humo de Tabaco
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