Almost 15 years have gone ever since the discovery of graphene as a single atom layer. Numerous papers have been published to demonstrate its high electron mobility, excellent thermal and mechanical as well as optical properties. We have recently seen more and more applications towards using graphene in commercial products. This paper is an attempt to review and summarize the current status of the research of the thermal properties of graphene and other 2D based materials including the manufacturing and characterization techniques and their applications, especially in electronics and power modules. It is obvious from the review that graphene has penetrated the market and gets more and more applications in commercial electronics thermal management context. In the paper, we also made a critical analysis of how mature the manufacturing processes are; what are the accuracies and challenges with the various characterization techniques and what are the remaining questions and issues left before we see further more applications in this exciting and fascinating field.
Few data are available on the incidence of deep vein thrombosis (DVT) in critically ill COVID-19 with thrombosis prophylaxis. This study retrospectively included 88 patients in the ICU with critically ill COVID-19 at Jinyintan Hospital in Wuhan, China. All patients underwent compression ultrasonography for identifying DVT. Firth logistic regression was used to examine the association of DVT with sex, age, hypoalbuminemia, D-dimer, and SOFA score. The median (interquartile range [IQR]) age and SOFA score of 88 patients were 63 (55-71) years old and 5 (4-6), respectively. Despite all patients receiving guideline-recommended low-molecular-weight heparin (LMWH) thromboprophylaxis, the incidence of DVT was 46% (95% CI 35-56%). Proximal DVT was recognized in 9% (95% CI 3-15%) of the patients, while 46% (95% CI 35-56%) of patients had distal DVT. All of the proximal DVT combined with distal DVT. Risk factors of DVT extension occurred in all distal DVT patients. As Padua score ≥ 4 or IMPROVE score ≥ 2, 53% and 46% of patients had DVT, respectively. Mortality was higher in patients with acute DVT (30%) compared with non-DVT (17%), but did not reach statistical significance. Hypoalbuminemia (odds ratio [OR], 0.17; 95% CI 0.06-0.05, P = 0.001), higher SOFA score (OR per IQR, 2.07; 95% CI 1.38-3.39, P = 0.001), and elevated D-dimer (OR per IQR, 1.04; 95% CI 1.03-1.84, P = 0.029) were significant DVT risk factors in multivariable analyses. High incidence of DVT was identified in patients with critically ill COVID-19, despite the use of guideline-recommended pharmacologic thromboprophylaxis. The presence of hypoalbuminemia, higher SOFA score, and elevated D-dimer were significantly independent risk factors of DVT. More effective VTE prevention and management strategies may need to be addressed. Keywords Deep vein thrombosis • Hypoalbuminemia • D-dimer • SOFA score • Coronavirus Highlights • The incidence of DVT in patients with critically ill COVID-19 was 46% despite the use of guideline-recommended thromboprophylaxis. • The presence of hypoalbuminemia, SOFA score, and elevated D-dimer were predictors of DVT. • More effective VTE prevention strategies are necessary for patients with critically ill COVID-19.
Due to substantial phonon scattering induced by various structural defects, the in-plane thermal conductivity (K) of graphene films (GFs) is still inferior to the commercial pyrolytic graphite sheet (PGS). Here, the problem is solved by engineering the structures of GFs in the aspects of grain size, film alignment, and thickness, and interlayer binding energy. The maximum K of GFs reaches to 3200 W m K and outperforms PGS by 60%. The superior K of GFs is strongly related to its large and intact grains, which are over four times larger than the best PGS. The large smooth features about 11 µm and good layer alignment of GFs also benefit on reducing phonon scattering induced by wrinkles/defects. In addition, the presence of substantial turbostratic-stacking graphene is found up to 37% in thin GFs. The lacking of order in turbostratic-stacking graphene leads to very weak interlayer binding energy, which can significantly decrease the phonon interfacial scattering. The GFs also demonstrate excellent flexibility and high tensile strength, which is about three times higher than PGS. Therefore, GFs with optimized structures and properties show great potentials in thermal management of form-factor-driven electronics and other high-power-driven systems.
The selectivity of the adaptive immune response is based on the enormous diversity of T and B cell antigen-specific receptors. The immune repertoire, the collection of T and B cells with functional diversity in the circulatory system at any given time, is dynamic and reflects the essence of immune selectivity. In this article, we review the recent advances in immune repertoire study of infectious diseases, which were achieved by traditional techniques and high-throughput sequencing (HTS) techniques. HTS techniques enable the determination of complementary regions of lymphocyte receptors with unprecedented efficiency and scale. This progress in methodology enhances the understanding of immunologic changes during pathogen challenge and also provides a basis for further development of novel diagnostic markers, immunotherapies, and vaccines.
The evidence is quite limited regarding the constituents of fine particulate matter (PM) responsible for lung dysfunction. We designed a time-series panel study in 28 patients to examine the effects of 10 major constituents of PM on lung function with repeated daily measurements from December 2012 to May 2013 in Shanghai, China. We applied a linear mixed-effect model combined with a distributed lag model to estimate the cumulative effects of PM constituents on morning/evening forced expiratory volume in 1-s (FEV) and peak expiratory flow (PEF) over a week. The cumulative decreases in morning FEV, evening FEV, morning PEF and evening PEF associated with an interquartile range (35.8 μg/m) increase in PM concentrations were 33.49 [95% confidence interval(CI):2.45,54.53] mL, 16.80 (95%CI:3.75,29.86) mL, 4.48 (95%CI:2.30,6.66) L/min, and 1.31 (95%CI:-0.85,3.47) L/min, respectively. These results were not substantially changed after adjusting for gases in two-pollutant models. The associations of elemental carbon (EC) and nitrates with morning/evening FEV, and the associations of EC and sulfates with morning PEF were robust after controlling for PM This study demonstrated that short-term exposure to PM was associated with reduced pulmonary function. Some constituents (EC, sulfate and nitrate) may be responsible for the detrimental effects.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.