| 1. |
- Chen, Shujing, et al.
(författare)
-
Scalable production of thick graphene films for next generation thermal management applications
- 2020
-
Ingår i: Carbon. - : Elsevier BV. - 0008-6223. ; 167, s. 270-277
-
Tidskriftsartikel (refereegranskat)abstract
- With the increasing demand on integration and better performance of portable electronics devices, the system operation temperatures are expected to continue to increase, leading eventually to degeneration in functional performance and reliability. Therefore, demand for thermal management materials that effectively spread heat and reduce heat density is urgent. The existing solution of pyrolytic graphite film (PGF) is unsatisfactory due to their low heat flux carrying capacity or low thermal conductivity, as well as poor mechanical performance. This work solves the problem by substituting ultra-thick (>75 mm) graphene film (GF) for PGF, offering more than three times higher heat flux carrying capacity. The conjugation of large crystallinity and firm structures endows GFs with excellent thermal conductive performance (up to 1204 +/- 35 W m(-1) K-1), great heat flux carrying capacity, and good foldability (5000 cycles folding). In addition to this, such a GF is produced based on an economically efficient and quasi industrial method incorporating continuous high-pressure homogenization processing (HPH), indicating an enormous potential as a new pathway to thermal management applications.
|
|
| 2. |
- Bao, Chunxiong, et al.
(författare)
-
Bidirectional optical signal transmission between two identical devices using perovskite diodes
- 2020
-
Ingår i: NATURE ELECTRONICS. - : NATURE PUBLISHING GROUP. - 2520-1131. ; 3:3, s. 156-164
-
Tidskriftsartikel (refereegranskat)abstract
- A solution-processed perovskite diode that functions as both optical transmitter and receiver can be used to build a monolithic pulse sensor and a bidirectional optical communication system. The integration of optical signal generation and reception into one device-thus allowing a bidirectional optical signal transmission between two identical devices-is of value in the development of miniaturized and integrated optoelectronic devices. However, conventional solution-processable semiconductors have intrinsic material and design limitations that prevent them from being used to create such devices with a high performance. Here we report an efficient solution-processed perovskite diode that is capable of working in both emission and detection modes. The device can be switched between modes by changing the bias direction, and it exhibits light emission with an external quantum efficiency of over 21% and a light detection limit on a subpicowatt scale. The operation speed for both functions can reach tens of megahertz. Benefiting from the small Stokes shift of perovskites, our diodes exhibit a high specific detectivity (more than 2 x 10(12) Jones) at its peak emission (~804 nm), which allows an optical signal exchange between two identical diodes. To illustrate the potential of the dual-functional diode, we show that it can be used to create a monolithic pulse sensor and a bidirectional optical communication system.
|
|
| 3. |
- Chen, Jie, et al.
(författare)
-
Origin of the spatial consistency of summer precipitation variability between the Mongolian Plateau and the mid-latitude East Asian summer monsoon region
- 2020
-
Ingår i: Science China. Earth Sciences. - : Springer Science and Business Media LLC. - 1674-7313 .- 1869-1897. ; 63:8, s. 1199-1208
-
Tidskriftsartikel (refereegranskat)abstract
- The Mongolian Plateau (MP) is located in the eastern part of arid Central Asia (ACA). Climatically, much of the MP is dominated by the westerly circulation and has an arid and semi-arid climate; however, the eastern part of the MP is also influenced by the East Asian summer monsoon (EASM) and has a humid and semi-humid climate. Several studies have shown that precipitation variability in the MP differs from that in western ACA but is consistent with that in the EASM region. Here we use monthly precipitation data for 1979-2016 to characterize and determine the origin of the summer precipitation variability of the MP and the EASM region. The results show that the MP and the mid-latitude EASM region exhibit a consistent pattern of precipitation variability on interannual and decadal timescales; specifically, the consistent regions are the MP and North and Northeast China. We further investigated the physical mechanisms responsible for the consistent interdecadal precipitation variability between the MP and the mid-latitude EASM region, and found that the mid-latitude wave train over Eurasia, with positive (negative) geopotential height anomalies over the North Atlantic and ACA and negative (positive) geopotential height anomalies over Europe and the MP, is the key factor responsible for the consistency of precipitation variability in the MP and the mid-latitude EASM region. The positive anomalies over the North Atlantic and ACA and negative anomalies over Europe and the MP would enhance the transport of westerly and monsoon moisture to the MP and North and Northeast China. They could also strengthen the Northeast Asian low, enhance the EASM, and trigger the anomalous ascending motion over the MP which promotes precipitation in the MP and in the mid-latitude EASM region. Overall, our results help explain the spatial variations of paleo-precipitation/humidity reconstructions in East Asia and clarify the reasons for the consistency of the regional climate.
|
|
| 4. |
- Cheng, Jie, et al.
(författare)
-
Preparation of Surface Modified Ceria Nanoparticles as Abrasives for the Application of Chemical Mechanical Polishing (CMP)
- 2020
-
Ingår i: ECS Journal of Solid State Science and Technology. - : ELECTROCHEMICAL SOC INC. - 2162-8769 .- 2162-8777. ; 9:2
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, a method to improve the chemical mechanical polishing (CMP) performance of ceria as abrasive particles was proposed. Surface doping of ceria nanoparticles was realized by incipient impregnation method, in order to improve its valance change properties (Ce3+/Ce4+). This study presents detailed characterization of the lanthanide-doped CeO2 by both experimental methods and density functional theory (DFT) calculation. The dispersion stability of the doped ceria nanoparticles in CMP slurries are investigated. Results show that the doped CeO2 nanoparticles exhibit more oxygen vacancies and higher content of Ce3+ compared with the pristine CeO2. Good dispersion stability of the doped CeO2 nanoparticles could be achieved by adding dispersants in the CMP slurries.
|
|
| 5. |
- Cheng, Jie, et al.
(författare)
-
RE (La, Nd and Yb) doped CeO2 abrasive particles for chemical mechanical polishing of dielectric materials : Experimental and computational analysis
- 2020
-
Ingår i: Applied Surface Science. - : ELSEVIER. - 0169-4332 .- 1873-5584. ; 506
-
Tidskriftsartikel (refereegranskat)abstract
- Ce3+ in CeO2, rather than Ce4+, is believed to provide assistance to the breaking up of Si-O bond during chemical mechanical polishing (CMP) of silica. In the paper, lanthanide metals (La, Nd and Yb) doped CeO2 nanoparticles were synthesized by modified incipient impregnation method in order to improve the content of Ce3+ in CeO2 as polishing. X-ray photoelectron spectroscopy (XPS) experiments and density function theory (DFT) calculation demonstrate this approach could achieve surface doping of CeO2 nanoparticles, and facilitates the formation of oxygen vacancy and Ce3+ content. CMP experiments show that the polishing rate and the surface quality of silica wafer are obviously improved by using the doped CeO2 as abrasive particles. Especially for Nd/CeO2, content of Ce3+ increases from 0.146 to 0.235, the polishing rate of silica is accelerated by 29.6% in alkaline slurries, and a better surface quality (Sa = 9.6 angstrom) is obtained.
|
|
| 6. |
- Huang, Joyce Y., et al.
(författare)
-
Circulating markers of cellular immune activation in prediagnostic blood sample and lung cancer risk in the Lung Cancer Cohort Consortium (LC3)
- 2020
-
Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 146:9, s. 2394-2405
-
Tidskriftsartikel (refereegranskat)abstract
- Cell-mediated immune suppression may play an important role in lung carcinogenesis. We investigated the associations for circulating levels of tryptophan, kynurenine, kynurenine:tryptophan ratio (KTR), quinolinic acid (QA) and neopterin as markers of immune regulation and inflammation with lung cancer risk in 5,364 smoking-matched case-control pairs from 20 prospective cohorts included in the international Lung Cancer Cohort Consortium. All biomarkers were quantified by mass spectrometry-based methods in serum/plasma samples collected on average 6 years before lung cancer diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with individual biomarkers were calculated using conditional logistic regression with adjustment for circulating cotinine. Compared to the lowest quintile, the highest quintiles of kynurenine, KTR, QA and neopterin were associated with a 20-30% higher risk, and tryptophan with a 15% lower risk of lung cancer (all p(trend) < 0.05). The strongest associations were seen for current smokers, where the adjusted ORs (95% CIs) of lung cancer for the highest quintile of KTR, QA and neopterin were 1.42 (1.15-1.75), 1.42 (1.14-1.76) and 1.45 (1.13-1.86), respectively. A stronger association was also seen for KTR and QA with risk of lung squamous cell carcinoma followed by adenocarcinoma, and for lung cancer diagnosed within the first 2 years after blood draw. This study demonstrated that components of the tryptophan-kynurenine pathway with immunomodulatory effects are associated with risk of lung cancer overall, especially for current smokers. Further research is needed to evaluate the role of these biomarkers in lung carcinogenesis and progression.
|
|
| 7. |
- Huang, Liping, et al.
(författare)
-
Interim effects of salt substitution on urinary electrolytes and blood pressure in the China Salt Substitute and Stroke Study (SSaSS).
- 2020
-
Ingår i: American Heart Journal. - : Elsevier BV. - 0002-8703 .- 1097-6744. ; 221, s. 136-145
-
Tidskriftsartikel (refereegranskat)abstract
- The Salt Substitute and Stroke Study is an ongoing 5-year large-scale cluster randomized trial investigating the effects of potassium-enriched salt substitute compared to usual salt on the risk of stroke. The study involves 600 villages and 20,996 individuals in rural China. Intermediate risk markers were measured in a random subsample of villages every 12 months over 3 years to track progress against key assumptions underlying study design. Measures of 24-hour urinary sodium, 24-hour urinary potassium, blood pressure and participants' use of salt substitute were recorded, with differences between intervention and control groups estimated using generalized linear mixed models. The primary outcome of annual event rate in the two groups combined was determined by dividing confirmed fatal and non-fatal strokes by total follow-up time in the first 2 years. The mean differences (95% CI) were -0.32 g (-0.68 to 0.05) for 24-hour urinary sodium, +0.77 g (+0.60 to +0.93) for 24-hour urinary potassium, -2.65 mmHg (-4.32 to -0.97) for systolic blood pressure and +0.30 mmHg (-0.72 to +1.32) for diastolic blood pressure. Use of salt substitute was reported by 97.5% in the intervention group versus 4.2% in the control group (P<.0001). The overall estimated annual event rate for fatal and non-fatal stroke was 3.2%. The systolic blood pressure difference and the annual stroke rate were both in line with the statistical assumptions underlying study design. The trial should be well placed to address the primary hypothesis at completion of follow-up.
|
|
| 8. |
- Ntalla, Ioanna, et al.
(författare)
-
Multi-ancestry GWAS of the electrocardiographic PR interval identifies 202 loci underlying cardiac conduction
- 2020
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 11:1
-
Tidskriftsartikel (refereegranskat)abstract
- The electrocardiographic PR interval reflects atrioventricular conduction, and is associated with conduction abnormalities, pacemaker implantation, atrial fibrillation (AF), and cardiovascular mortality. Here we report a multi-ancestry (N=293,051) genome-wide association meta-analysis for the PR interval, discovering 202 loci of which 141 have not previously been reported. Variants at identified loci increase the percentage of heritability explained, from 33.5% to 62.6%. We observe enrichment for cardiac muscle developmental/contractile and cytoskeletal genes, highlighting key regulation processes for atrioventricular conduction. Additionally, 8 loci not previously reported harbor genes underlying inherited arrhythmic syndromes and/or cardiomyopathies suggesting a role for these genes in cardiovascular pathology in the general population. We show that polygenic predisposition to PR interval duration is an endophenotype for cardiovascular disease, including distal conduction disease, AF, and atrioventricular pre-excitation. These findings advance our understanding of the polygenic basis of cardiac conduction, and the genetic relationship between PR interval duration and cardiovascular disease. On the electrocardiogram, the PR interval reflects conduction from the atria to ventricles and also serves as risk indicator of cardiovascular morbidity and mortality. Here, the authors perform genome-wide meta-analyses for PR interval in multiple ancestries and identify 141 previously unreported genetic loci.
|
|
| 9. |
- Sun, Peng, et al.
(författare)
-
Scalable three-dimensional Ni 3 P-based composite networks for flexible asymmertric supercapacitors
- 2020
-
Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947. ; 380
-
Tidskriftsartikel (refereegranskat)abstract
- Flexible energy storage devices are of great importance in future wearable electronics. To achieve the popularization of these flexible equipments, it is urgent to develop proper productive method for easily scaling up high performance flexible electrode materials. Herein, a three-dimensional nano-network composite material based on Ni3P is designed on flexible carbon felt (CF). The network induced by the introduction of sulfonated polystyrene combines advantages of excellent redox ability of the Ni3P, great conductivity of NiCo alloy and fast electric double layer contribution of carbon. It shows a great energy storage performance and an excellent balance between areal and gravimetric capacitance (1.76 F cm−2 and 1048 F g−1), which are beneficial to the actual application. Besides, this CF@NiCoNiPC can be easily produced in a large-scale due to the simple and low-cost synthetic method. The CF@NiCoNiPC can be further fabricated into an asymmetric supercapacitor (ASC), which demonstrates an excellent capacitance of 516.7 mF cm−2 (170.5 F g−1) and long-term stability of 25,000 charging and discharging cycles (83% retentions). Excitingly, the ASC presents good mechanical performance with 92% capacitance retention after 1000 bending cycles. Three tandem ASCs can easily power a red LED for several minutes when charged for only 20 s even under a bent state, indicating the great potential in future flexible energy storage devices.
|
|
| 10. |
- Teng, Fei, et al.
(författare)
-
Automatic Medical Code Assignment via Deep Learning Approach for Intelligent Healthcare
- 2020
-
Ingår i: IEEE journal of biomedical and health informatics. - : Institute of Electrical and Electronics Engineers (IEEE). - 2168-2194 .- 2168-2208. ; 24:9, s. 2506-2515
-
Tidskriftsartikel (refereegranskat)abstract
- With the development of healthcare 4.0, there has been an explosion in the amount of data such as image, medical text, physiological signals, lab tests, etc. Among them, medical records provide a complete picture of the associated clinical events. However, the processing of medical texts is difficult because they are structurally free, diverse in style, and have subjective factors. Assigning metadata codes from the International Classification of Diseases (ICD) presents a standardized way of indicating diagnoses and procedures, so it becomes a mandatory process for understanding medical records to make better clinical and financial decisions. Such a manual encoding task is time-consuming, error-prone and expensive. In this paper, we proposed a deep learning approach and a medical topic mining method to automatically predict ICD codes from text-free medical records. The result of the F1 score on Medical Information Mart for Intensive Care (MIMIC-III) dataset increases by 5% over the state of art. It also suitable for multiple ICD versions and languages. For the specific disease, atrial fibrillation, the F1 score is up to 96% and 93.3% using in-house ICD-10 datasets and MIMIC-III datasets, respectively. We developed an Artificial Intelligence based coding system, which can greatly improve the efficiency and accuracy of human coders, and meanwhile accelerate the secondary use for clinical informatics.
|
|
