Infrared anomalies in ultrathin Ti3C2Tx MXene films

Visible transparent but infrared reflective materials are ideal candidates for both transparent conductive films and low-emissivity glass, which are highly desired in a broad variety of areas such as touchscreens and displays, photovoltaics, smart windows, and antistatic coatings. Ultrathin Ti3C2Tx MXene films are emerging as promising low-emissivity transparent candidates. However, the fundamental IR properties of Ti3C2Tx has not been revealed experimentally due to daunting challenges in the preparation of continuous, large-area, and ultrathin films of optical quality on flat substrates. Herein, we proposed a tape-free transfer method that can help prepare centimeter-size and ultrathin (down to 8 nm) Ti3C2Tx films on diverse optical substrates. Benefitting from this method, the refractive index and permittivity for Ti3C2Tx were successfully measured. Ti3C2Tx films exhibit large in-plane permittivity in the IR region, yielding maximum IR reflectance of 88% for bulk films. Interestingly, three anomalies were found in ultrathin Ti3C2Tx films: strong dispersion in the permittivity, interlayer space-dependent optical properties, and abnormally high IR absorption for a 15-nm-thick film. These anomalies are important guidelines in the design of Ti3C2Tx-based low-emissivity transparent films and other related devices, and may inspire other intriguing applications such as ultrathin IR absorption coatings and tunable IR optical devices

Evaluating the impact of blowing-snow sea salt aerosol on springtime BrO and O3 in the Arctic

We use the GEOS-Chem chemical transport model to examine the influence of bromine release from blowingsnow sea salt aerosol (SSA) on springtime bromine activation and O3 depletion events (ODEs) in the Arctic lower troposphere. We evaluate our simulation against observations of tropospheric BrO vertical column densities (VCDtropo) from the GOME-2 (second Global Ozone Monitoring Experiment) and Ozone Monitoring Instrument (OMI) spaceborne instruments for 3 years (2007-2009), as well as against surface observations of O3. We conduct a simulation with blowingsnow SSA emissions from first-year sea ice (FYI; with a surface snow salinity of 0.1 psu) and multi-year sea ice (MYI; with a surface snow salinity of 0.05 psu), assuming a factor of 5 bromide enrichment of surface snow relative to seawater. This simulation captures the magnitude of observed March-April GOME-2 and OMI VCDtropo to within 17 %, as well as their spatiotemporal variability (r D 0:76-0.85). Many of the large-scale bromine explosions are successfully reproduced, with the exception of events in May, which are absent or systematically underpredicted in the model. If we assume a lower salinity on MYI (0.01 psu), some of the bromine explosions events observed over MYI are not captured, suggesting that blowing snow over MYI is an important source of bromine activation. We find that the modeled atmospheric deposition onto snow-covered sea ice becomes highly enriched in bromide, increasing from enrichment factors of ~ 5 in September-February to 10-60 in May, consistent with composition observations of freshly fallen snow. We propose that this progressive enrichment in deposition could enable blowing-snow-induced halogen activation to propagate into May and might explain our late-spring underestimate in VCDtropo. We estimate that the atmospheric deposition of SSA could increase snow salinity by up to 0.04 psu between February and April, which could be an important source of salinity for surface snow on MYI as well as FYI covered by deep snowpack. Inclusion of halogen release from blowing-snow SSA in our simulations decreases monthly mean Arctic surface O3 by 4-8 ppbv (15 %-30 %) in March and 8-14 ppbv (30 %-40 %) in April. We reproduce a transport event of depleted O3 Arctic air down to 40 N observed at many sub-Arctic surface sites in early April 2007. While our simulation captures 25 %-40 % of the ODEs observed at coastal Arctic surface sites, it underestimates the magnitude of many of these events and entirely misses 60 %-75 % of ODEs. This difficulty in reproducing observed surface ODEs could be related to the coarse horizontal resolution of the model, the known biases in simulating Arctic boundary layer exchange processes, the lack of detailed chlorine chemistry, and/or the fact that we did not include direct halogen activation by snowpack chemistry

Progress in Electrocatalytic Hydrogen Evolution Based on Monolayer Molybdenum Disulfide

Energy and environmental issues raise higher demands on the development of a sustainable energy system, and the electrocatalytic hydrogen evolution is one of the most important ways to realize this goal. Two-dimensional (2D) materials represented by molybdenum disulfide (MoS2) have been widely investigated as an efficient electrocatalyst for the hydrogen evolution. However, there are still some shortcomings to restrict the efficiency of MoS2 electrocatalyst, such as the limited numbers of active sites, lower intrinsic catalytic activity and poor interlayer conductivity. In this review, the application of monolayer MoS2 and its composites with 0D, 1D, and 2D nanomaterials in the electrocatalytic hydrogen evolution were discussed. On the basis of optimizing the composition and structure, the numbers of active sites, intrinsic catalytic activity, and interlayer conductivity could be significantly enhanced. In the future, the study would focus on the structure, active site, and interface characteristics, as well as the structure-activity relationship and synergetic effect. Then, the enhanced electrocatalytic activity of monolayer MoS2 can be achieved at the macro, nano and atomic levels, respectively. This review provides a new idea for the structural design of two-dimensional electrocatalytic materials. Meanwhile, it is of great significance to promote the study of the structure-activity relationship and mechanism in catalytic reactions

Diagnostic accuracy and reproducibility of optical flow ratio for functional evaluation of coronary stenosis in a prospective series

Background: Evaluating prospectively the feasibility, accuracy and reproducibility of optical flow ratio (OFR), a novel method of computational physiology based on optical coherence tomography (OCT).Methods and results: Sixty consecutive patients (76 vessels) underwent prospectively OCT, angiography- based quantitative flow ratio (QFR) and fractional flow ratio (FFR). OFR was computed offline in a central core-lab by analysts blinded to FFR. OFR was feasible in 98.7% of the lesions and showed excellent agreement with FFR (ICCa = 0.83, r = 0.83, slope = 0.80, intercept = 0.17, kappa = 0.84). The area under curve to predict an FFR ≤ 0.80 was 0.95, higher than for QFR (0.91, p = 0.115) and for minimal lumen area (0.64, p < 0.001). Diagnostic accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio and negative likelihood ratio were 93%, 92%, 93%, 88%, 96%, 13.8, 0.1, respectively. Median time to obtain OFR was 1.07 (IQR: 0.98–1.16) min, with excellent intraobserver and interobserver reproducibility (0.97 and 0.95, respectively). Pullback speed had negligible impact on OFR, provided the same coronary segment were imaged (ICCa = 0.90, kappa = 0.697).Conclusions: The prospective computation of OFR is feasible and reproducible in a real-world series,resulting in excellent agreement with FFR, superior to other image-based methods

Effects of Sea Salt Aerosol Emissions for Marine Cloud Brightening on Atmospheric Chemistry : Implications for Radiative Forcing

Marine cloud brightening (MCB) is proposed to offset global warming by emitting sea salt aerosols to the tropical marine boundary layer, which increases aerosol and cloud albedo. Sea salt aerosol is the main source of tropospheric reactive chlorine (Cly) and bromine (Bry). The effects of additional sea salt on atmospheric chemistry have not been explored. We simulate sea salt aerosol injections for MCB under two scenarios (212–569 Tg/a) in the GEOS-Chem global chemical transport model, only considering their impacts as a halogen source. Globally, tropospheric Cly and Bry increase (20–40%), leading to decreased ozone (−3 to −6%). Consequently, OH decreases (−3 to −5%), which increases the methane lifetime (3–6%). Our results suggest that the chemistry of the additional sea salt leads to minor total radiative forcing compared to that of the sea salt aerosol itself (~2%) but may have potential implications for surface ozone pollution in tropical coastal regions

Angiography-based superficial wall strain of de novo stenotic coronary arteries:serial assessment of vessels treated with bioresorbable scaffold or drug-eluting stent

Objectives: This study sought to present an angiography-based computational model for serial assessment of superficial wall strain (SWS, dimensionless) of de-novo coronary stenoses treated with either bioresorbable scaffold (BRS) or drug-eluting stent (DES). Background: A novel method for SWS allows the assessment of the mechanical status of arteries in-vivo, which may help for predicting cardiovascular outcomes. Methods: Patients with arterial stenosis treated with BRS (n = 21) or DES (n = 21) were included from ABSORB Cohort B1 and AIDA trials. The SWS analyses were performed along with quantitative coronary angiography (QCA) at pre-PCI, post-PCI, and 5-year follow-up. Measurements of QCA and SWS parameters were quantified at the treated segment and adjacent 5-mm proximal and distal edges. Results: Before PCI, the peak SWS on the ‘to be treated’ segment (0.79 ± 0.36) was significantly higher than at both virtual edges (0.44 ± 0.14 and 0.45 ± 0.21; both p &lt; 0.001). The peak SWS in the treated segment significantly decreased by 0.44 ± 0.13 (p &lt; 0.001). The surface area of high SWS decreased from 69.97mm2 to 40.08mm2 (p = 0.002). The peak SWS in BRS group decreased to a similar extent (p = 0.775) from 0.81 ± 0.36 to 0.41 ± 0.14 (p &lt; 0.001), compared with DES group from 0.77 ± 0.39 to 0.47 ± 0.13 (p = 0.001). Relocation of high SWS to device edges was often observed in both groups after PCI (35 of 82 cases, 41.7 %). At follow-up of BRS, the peak SWS remained unchanged compared to post-PCI (0.40 ± 0.12 versus 0.36 ± 0.09, p = 0.319). Conclusion: Angiography-based SWS provided valuable information about the mechanical status of coronary arteries. Device implantation led to a significant decrease of SWS to a similar extent with either polymer-based scaffolds or permanent metallic stents.</p

中国人日本語専攻生の学術コミュニティへの参加過程の分析 : 中国の大学から日本の大学院へ

華中科技大学一橋大学大学院 博士課程一橋大学大学院 博士課程一橋大学大学院 博士課程Huazhong University of Science and TechnologyPh.D. Student, Hitotsubashi UniversityPh.D. Student, Hitotsubashi UniversityPh.D. Student, Hitotsubashi University本稿では，中国から来日した一人の日本語専攻生Iさんを対象に，彼女が来日前及び来日後に参加した複数のコミュニティへの参加過程を分析した。調査はIさんに対して一年半に渡り，5回の半構造化インタビューを行い，そのデータをSCAT（Steps for Coding and Theorization）を用いて分析した。分析の結果，中国の大学の日本語授業とゼミ，日本の大学（院）の授業とゼミ，また，より大きな研究者コミュニティや学術コミュニティに参加することを通して，Iさんは学術コミュニティへの参加姿勢が能動的になったことが確認された。分析の結果に基づき，筆者らは学術コミュニティ間の移動が中国人日本語専攻生に何をもたらしたのかをアイデンティティ変容の側面から考察した。その結果，中国人日本語専攻生の持つ固有のアイデンティティに加え，日本語学習者と日本語使用者が統合された「日本語話者」，さらに大学院に進学することによるキャリア転換がもたらす「〇〇専門家」という多層なアイデンティティの獲得があったことが分かった。最後に，本調査結果を踏まえた日本語教育への提言として，「学習者と接する際の見方の転換」，「キャリア形成を踏まえた上での日本語教育」，及び「学びの実感を生み出す授業の工夫」という三つを指摘した。The subject of this study is Ms. I, a Chinese-born Japanese-language graduate in Japan. We analyzed her participation process in multiple communities before and after arriving in Japan. The survey was conducted over the course of 1.5 years and involved 5 semi-structured interviews with Ms. I. We analyzed the interview data using the Steps for Coding and Theorization (SCAT). The results of the analysis showed that Ms. I\u27s participation in Japanese-language classes and seminars at her Chinese university, in classes and seminars at her Japanese university (graduate school), as well as in a wider community of researchers and the academic community, allowed her approach to participation to become more active and her identity to become more multi-layered. It then appears that her movement between the multiple communities transformed her Japanese from a learning content to a tool for participation. Moreover, it was suggested that her identity changed from that of a Japanese learner to that of a Japanese user and that her career movement from Japanese-major student to 〇〇 expert facilitated the formation of a new identity. Lastly, we pointed out a “change of the angle of observation on the Japanese learners,” “Japanese-language education as a foundation of career development,” and “classroom techniques to create student awareness of their own learning” as three suggestions for Japanese-language education

Late-life depression: Epidemiology, phenotype, pathogenesis and treatment before and during the COVID-19 pandemic

Late-life depression (LLD) is one of the most common mental disorders among the older adults. Population aging, social stress, and the COVID-19 pandemic have significantly affected the emotional health of older adults, resulting in a worldwide prevalence of LLD. The clinical phenotypes between LLD and adult depression differ in terms of symptoms, comorbid physical diseases, and coexisting cognitive impairments. Many pathological factors such as the imbalance of neurotransmitters, a decrease in neurotrophic factors, an increase in β-amyloid production, dysregulation of the hypothalamic-pituitary-adrenal axis, and changes in the gut microbiota, are allegedly associated with the onset of LLD. However, the exact pathogenic mechanism underlying LLD remains unclear. Traditional selective serotonin reuptake inhibitor therapy results in poor responsiveness and side effects during LLD treatment. Neuromodulation therapies and complementary and integrative therapies have been proven safe and effective for the treatment of LLD. Importantly, during the COVID-19 pandemic, modern digital health intervention technologies, including socially assistive robots and app-based interventions, have proven to be advantageous in providing personal services to patients with LLD

Case report: Targeted sequencing facilitates the diagnosis and management of rare multifocal pure ground-glass opacities with intrapulmonary metastasis

IntroductionTreatments for multiple ground-glass opacities (GGOs) for which the detection rate is increasing are still controversial. Next-generation sequencing (NGS) may provide additional key evidence for differential diagnosis or optimal therapeutic schedules.Case presentationWe first reported a rare case in which more than 100 bilateral pulmonary GGOs (91.7% of the GGOs were pure GGOs) were diagnosed as both multiple primary lung cancer and intrapulmonary metastasis. We performed NGS with an 808-gene panel to assess both somatic and germline alterations in tissues and plasma. The patient (male) underwent three successive surgeries and received osimertinib adjuvant therapy due to signs of metastasis and multiple EGFR-mutated tumors. The patient had multiple pure GGOs, and eight tumors of four pathological subtypes were evaluated for the clonal relationship. Metastasis, including pure GGOs and atypical adenomatous hyperplasia, was found between two pairs of tumors. Circulating tumor DNA (ctDNA) monitoring of disease status may impact clinical decision-making.ConclusionsSurgery combined with targeted therapies remains a reasonable alternative strategy for treating patients with multifocal GGOs, and NGS is valuable for facilitating diagnostic workup and adjuvant therapy with targeted drugs through tissue and disease monitoring via ctDNA