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Designing catalysts with highly active, selectivity, and stability for electrocatalytic CO2 to formate is currently a severe challenge. Herein, we developed an electronic structure engineering on carbon nano frameworks embedded with nitrogen and sulfur asymmetrically dual-coordinated indium active sites toward the efficient electrocatalytic CO2 reduction reaction. As expected, atomically dispersed In-based catalysts with In-S1N3 atomic interface with asymmetrically coordinated exhibited high efficiency for CO2 reduction reaction (CO2RR) to formate. It achieved a maximum Faradaic efficiency (FE) of 94.3% towards formate generation at −0.8 V vs. reversible hydrogen electrode (RHE), outperforming that of catalysts with In-S2N2 and In-N4 atomic interface. And at a potential of −1.10 V vs. RHE, In-S1N3 achieves an impressive Faradaic efficiency of 93.7% in flow cell. The catalytic performance of In-S1N3 sites was confirmed to be enhanced through in-situ X-ray absorption near-edge structure (XANES) measurements under electrochemical conditions. Our discovery provides the guidance for performance regulation of main group metal catalysts toward CO2RR at atomic scale. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) play a crucial role in energy catalysis due to their distinct coordination environment and high atomic utilization efficiency. This study focuses on the synthesis of a monatomic Cu catalyst with Cu-N1C1 coordination anchored to N-doped Ti3C2Tx MXene (Cu SA@N-Ti3C2Tx) to achieve efficient reduction of CO2 to CO. Detailed characterization, including morphology and multispectral analysis, confirmed the uniform distribution of asymmetrically coordinated Cu atoms in unsaturated C-Cu-N bridge fragments on Ti3C2Tx. The Cu SA@N-Ti3C2Tx catalyst exhibited an excellent CO selectivity with Faraday efficiency of 97.4% at −0.58 V vs. reversible hydrogen electrode (RHE) and satisfactory durability. The in situ X-ray absorption fine structure (XAFS) results confirmed that the carbon dioxide reduction reaction (CO2RR) product distribution is mainly affected by potential-dependent valence change of Cu species. These findings highlight the extensive potential of tuning coordination structure of MXene-based single-atom catalysts for CO2 reduction reactions. [ABSTRACT FROM AUTHOR]

In this paper, we derive closed form upper bounds on the error probability of low-density parity-check (LDPC) coded modulation schemes operating on quasi-static fading channels. The bounds are obtained from the so-called Fano-Gallager's tight bounding techniques, and can be readily calculated when the distance spectrum of the code is available. In deriving the bounds for multiple-input multiple-output (MIMO) systems, we assume the LDPC code is concatenated with the orthogonal space-time block code as an inner code. We obtain an equivalent single-input single-output (SISO) channel model for this concatenated coded-modulation system. The upper bounds derived here indicate good matches with simulation results of a complete transceiver system over Rayleigh and Rician MIMO fading channels in which the iterative detection and decoding algorithm is employed at the receiver. Index Terms--Tight union bounds, LDPC codes, space-time block code, MIMO systems, quasi-static fading channels.

The Daily Quality Assurance (DQA) for a proton modality is not standardized. The modern pencil beam scanning proton system is becoming a trend and an increasing number of proton centers with PBS are either under construction or in planning. The American Association of Physicists in Medicine has a Task Group 224 report published in 2019 for proton modality routine QA. Therefore, there is a clinical need to explore a DQA procedure to meet the TG 224 guideline. The MatriXX PT and a customized phantom were used for the dosimetry constancy checking. An OBI box was used for imaging QA. The MyQA(TM) software was used for logging the dosimetry results. An in‐house developed application was applied to log and auto analyze the DQA results. Another in‐house developed program "DailyQATrend" was used to create DQA databases for further analysis. All the functional and easy determined tasks passed. For dosimetry constancy checking, the outputs for four gantry rooms were within ±3% with room to room baseline differences within ±1%. The energy checking was within ±1%. The spot location checking from the baseline was within 0.63 mm and the spot size checking from the baseline was within −1.41 ± 1.27 mm (left–right) and −0.24 ± 1.27 mm (in–out) by averaging all the energies. We have found that there was also a trend for the beam energies of two treatment rooms slowly going down (0.76% per month and 0.48 per month) after analyzing the whole data trend with linear regression. A DQA program for a PBS proton system has been developed and fully implemented into the clinic. The DQA program meets the TG 224 guideline and has web‐based logging and auto treading functions. The clinical data show the DQA program is efficient and has the potential to identify the PBS proton system potential issue. [ABSTRACT FROM AUTHOR]

Background and Aim. Liver cirrhosis is often accompanied by insidious cardiac dysfunction. This retrospective cross-sectional study is aimed at exploring the correlation between serum cardiac markers and decompensating events in liver cirrhosis. Methods. Cirrhotic patients who were consecutively hospitalized between January 2016 and March 2019 were screened. Serum cardiac biomarkers at admission, including N-Terminal pro-B-type natriuretic peptide (NT-pro BNP), high-sensitivity cardiac troponin T (hs-cTnT), creatine kinase (CK), creatine kinase MB (CK-MB), and lactate dehydrogenase (LDH), were collected. Acute decompensating events at admission, primarily including ascites, acute gastrointestinal hemorrhage, and acute-on-chronic liver failure (ACLF), were recorded. Results. The NT-pro BNP level was significantly higher in cirrhotic patients with acute decompensating events than in those without any decompensating events (median: 140.75 pg/mL versus 41.86 pg/mL, P < 0.001). The NT-pro BNP level significantly correlated with ascites, acute gastrointestinal hemorrhage, and ACLF. The hs-cTnT level was significantly higher in cirrhotic patients with acute decompensating events than in those without decompensating events (median: 0.008 ng/mL versus 0.006 ng/mL, P = 0.007). The hs-cTnT level significantly correlated with acute gastrointestinal hemorrhage, but not ascites or ACLF. LDH (185.0 U/L versus 173.5 U/L, P = 0.281), CK (71 U/L versus 84 U/L, P = 0.157), and CK-MB (29.5 U/L versus 33.0 U/L, P = 0.604) levels were not significantly different between cirrhotic patients with and without acute decompensating events. Conclusion. The elevated NT-pro BNP level seems to be closely related to the development of acute decompensating events in liver cirrhosis. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the change of CT texture features of esophageal squamous cell carcinoma (ESC) during RT delivery and to correlate these changes with the RT responses and survival. Methods: A total of 61 ESC patients received radical RT were screened. Weekly CTs (4–6 sets for each patient) were acquired during RT. The tumors, normal esophageal mucosa tissue (NEC) of 5 cm and the spinal cord in the relevant area were delineated. CT texture features were extracted with a home-made tool. The changes of these features were analyzed by t-test. The correlations of the changes of features with RT responses and with patient survival were investigated by Pearson analysis. Results: The average changes were increased by 0.00072 ±0.00197 for coarseness, by 0.14 ±0.40 for entropy, and by 2.34 ±3.56 for strength. In addition, the average changes were reduced by 8.88 ±15.71cc for volume and by 0.07 ±0.11 for busyness. The changes of the coarseness, strength, STD and entropy in ESC were different for the good and poor response groups. The survival rate of the patients was significantly correlated with the change of coarseness and strength (P = 0.0027 and P = 0.0001). Conclusions: During RT, changes of CT texture features of ESC, e.g., coarseness, strength, STD, entropy and volume are correlated with radiation response and survival rate. With more clinical data and robust research, CT features, e.g., coarseness and strength, can be selected as outstanding imaging biomarkers for prediction of RT prognosis of ESC. [ABSTRACT FROM AUTHOR]

Hepatorenal syndrome (HRS) is a serious complication of liver cirrhosis, which is of pre-renal origin due to central volume depletion together with cardiac dysfunction and characterized by oliguria with severe urinary sodium retention and elevated serum creatinine levels. HRS is divided into HRS I, which is rapidly progressive and mostly seen in patients with decompensated liver cirrhosis, and HRS II, which progresses more slowly and is always accompanied by gross ascites. Liver transplantation is the best choice of treatment for HRS but rarely available. Current mainstay pharmacological therapies are vasoconstrictors, such as terlipressin, noradrenaline and dopamine, in combination with albumin. This paper aims to overview the current evidence regarding outcomes of terlipressin for the treatment of HRS. [ABSTRACT FROM AUTHOR]

Purpose: Limited by various human interventions and manual operations, the routine practice of online adaptive replanning (OLAR) is time consuming and impractical with the current planning technology. To accelerate OLAR and to minimize human efforts, the methods and software tools are developed to automate OLAR workflow and to use parallel processing during OLAR. Methods: Speedy online adaptive replanning SOLAR, a software tool, was developed to automate the OLAR workflow and to implement parallel operation in plan generation and contour editing. The SOLAR tool is designed to automate and monitor the operation of OLAR on multiple client workstations and to allow parallel manual contour editing and plan generation with multiple workstations. The performance of the SOLAR tool was tested on selected prostate and pancreatic cancer cases. Results: The SOLAR system has been tested in the clinical environment. With the automation and parallel operations, the operation time for OLAR can be reduced by 70%, allowing OLAR to be completed within 10 min for the tested prostate cancer cases and within 15 min for the pancreatic cancer cases. The SOLAR system generated superior plans compared to the standard repositioning method. Conclusion: SOLAR software was developed to accelerate online adaptive replanning workflow with automation and parallel operations. By reducing the time and human intervention, thus, reducing potential human error, the SOLAR solution would improve the practicality of OLAR. [ABSTRACT FROM AUTHOR]

A new differential evolution (DE) algorithm, JADE, is proposed to improve optimization performance by implementing a new mutation strategy "DE/current-to-pbest" with optional external archive and updating control parameters in an adaptive manner. The DE/current-to-pbest is a generalization of the classic "DE/current-to-best" while the optional archive operation utilizes historical data to provide information of progress direction. Both operations diversify the population and improve the convergence performance. The parameter adaptation automatically updates the control parameters to appropriate values and avoids a user's prior knowledge of the relationship between the parameter settings and the characteristics of optimization problems. It is thus helpful to improve the robustness of the algorithm. Simulation results show that JADE is better than, or at least comparable to, other classic or adaptive DE algorithms, the canonical particle swarm optimization, and other evolutionary algorithms from the literature in terms of convergence performance for a set of 20 benchmark problems. JADE with an external archive shows promising results for relatively high dimensional problems. In addition, it clearly shows that there is no fixed control parameter setting suitable for various problems or even at different optimization stages of a single problem. [ABSTRACT FROM AUTHOR]

Abstract An efficient algorithm for curve interpolation is proposed. The algorithm can produce a subdivision surface that can interpolate the predefined cubic B-spline curves by applying the Catmull-Clark scheme to a polygonal mesh containing "symmetric zonal meshes", which possesses some special properties. Many kinds of curve interpolation problems can be dealt with by this algorithm, such as interpolating single open curve or closed curve, a mesh of nonintersecting or intersecting curve. The interpolating surface is C² everywhere excepting at a finite number of points. At the same time, sharp creases can also be modeled on the limit subdivision surface by duplicating the vertices of the tagged edges of initial mesh, i.e. the surface is only CO along the cubic B-spline curve that is defined by the tagged edges. Because of being simple and easy to implement, this method can be used for product shape design and graphic software development. [ABSTRACT FROM AUTHOR]

Analysis of chemical composition characteristics of PM2.5 under different pollution degrees can reveal the changes of pollution sources. In order to make clear the evolution process of PM2.5 compositions in autumn and winter, PM2.5 samples were continuously collected and analyzed at Liaocheng city, China. The collected samples were classified as clean days (CLD), mild-moderate pollution days (MMD) and severe-serious pollution days (SSD). It was concluded that with the increase of pollution degrees, the concentrations of water-soluble ions and carbon components increased significantly, while elements only increased slightly. In addition, as the pollution degrees increased, the percentage of NO3−, SO42− and NH4+ increased significantly, from 23.0% in CLD to 49.0% in SSD, while the percentage of other components decreased, especially crust material. The PMF analyzed results showed that secondary transformation (36.7%), combustion sources (20.4%), secondary organic aerosols (SOA) (11.7%), vehicle sources (11%), dust (10.5%) and industrial processes (9.7%) were the main sources of PM2.5 during autumn and winter in Liaocheng. The contribution of secondary transformation reached 57% at the SSD level, which indicated that it was the main reason for the increase of PM2.5 concentrations. The air mass mainly came from five paths to Liaocheng. The secondary transformation contribution of the air mass with short transmission distance was higher, while the contribution of the dust was higher from the long distance. [ABSTRACT FROM AUTHOR]

Pollutants emission, meteorological conditions, secondary formation, and pollutants transport are the main reasons for air pollution. A comprehensive air pollution analysis was conducted from the above four aspects in the autumn–winter seasons of 2017–2018 and 2018–2019 at Xingtai, China. In addition, the relationship between PM2.5 and O3 was also studied from the aspects of secondary formation and meteorological conditions to find the rules of cooperative management of PM2.5 and O3 combined pollution. Taking measures of concentrated and clean heating and controlling biomass burning could make the concentrations of EC, K+ and SO42− decrease. The variation trends of PM2.5 and O3 concentration in the autumn–winter season of Xingtai were different, and with the increase in secondary formation effects, the concentration of O3 decreased. Furthermore, the key meteorological conditions that affected O3 and PM2.5 formation were temperature and relative humidity, respectively. The relationships of NOR (nitrate oxidation rate) and SOR (sulfate oxidation rate) against temperature presented a "U" shape, suggesting that gas-phase oxidation and gas–solid-phase oxidation were all suppressed at a temperature of around 4 °C. The cities located in the east had more pollutant transporting effects during the pollution processes of Xingtai, and the main transport routes of O3 and PM2.5 were not all the same. [ABSTRACT FROM AUTHOR]

Beijing-Tianjin-Hebei (BTH) and its surrounding areas are one of the most polluted regions in China. Xingtai, as a heavy industrial city of BTH and its surrounding areas, has been experiencing a severe PM2.5 pollution in recent years, characterized by extremely high concentrations of PM2.5. In 2014, PM2.5 mass concentrations monitored by online instruments in urban areas of Xingtai were 116, 77, 128, and 200 µg m−3 in spring, summer, autumn and winter, respectively, with annually average concentrations of 130 µg m−3 exhibiting 3.7 times higher than National Ambient Air Quality Standard (NAAQS) value for PM2.5 (35 µg m−3). To identify PM2.5 emission sources, ambient PM2.5 samples were collected during both cold and warm periods in 2014 in urban areas of Xingtai. Organic carbon (OC), sulfate, nitrate, ammonium and elemental carbon (EC) were the dominant components of PM2.5, accounting for 13%, 11%, 12%, 11% and 8% in the cold period, respectively, and 11%, 12%, 9%, 6%, and 5% in the warm period, respectively. Source apportionment results indicated that coal combustion (24.4%) was the largest PM2.5 emission source, followed by secondary sulfate (22.2%), secondary nitrate (18.4%), vehicle exhaust dust (12.4%), fugitive dust (9.7%), construction dust (5.5%), soil dust (3.4%) and metallurgy dust (1.6%). Based on PM2.5 source apportionment results, some emission control measures, such as replacing bulk coal with clean energy sources, controlling coal consumption by coal-fired boiler upgrades, halting operations of unlicensed small polluters, and controlling fugitive and VOCs emission, were proposed to be implemented in order to improve Xingtai's ambient air quality. [ABSTRACT FROM AUTHOR]

To elucidate the air pollution characteristics of northern China, airborne PM 10 (atmospheric dynamic equivalent diameter ≤ 10 μm) and PM 2.5 (atmospheric dynamic equivalent diameter ≤ 2.5 μm) were sampled in three different functional areas (Yuzhong County, Xigu District and Chengguan District) of Lanzhou, and their chemical composition (elements, ions, carbonaceous species) was analyzed. The results demonstrated that the highest seasonal mean concentrations of PM 10 (369.48 μg/m 3 ) and PM 2.5 (295.42 μg/m 3 ) were detected in Xigu District in the winter, the lowest concentration of PM 2.5 (53.15 μg/m 3 ) was observed in Yuzhong District in the fall and PM 10 (89.60 μg/m 3 ) in Xigu District in the fall. The overall average OC/EC (organic carbon/elemental carbon) value was close to the representative OC/EC ratio for coal consumption, implying that the pollution of Lanzhou could be attributed to the burning of coal. The content of SNA (the sum of sulfate, nitrate, ammonium, SNA) in PM 2.5 in Yuzhong County was generally lower than that at other sites in all seasons. The content of SNA in PM 2.5 and PM 10 in Yuzhong County was generally lower than that at other sites in all seasons (0.24–0.38), indicating that the conversion ratios from precursors to secondary aerosols in the low concentration area was slower than in the area with high and intense pollutants. Six primary particulate matter sources were chosen based on positive matrix factorization (PMF) analysis, and emissions from dust, secondary aerosols, and coal burning were identified to be the primary sources responsible for the particle pollution in Lanzhou. [ABSTRACT FROM AUTHOR]

Beijing suffered from serious air pollution in October, 2011 with the occurrence of three continuous episodes. Here we analyze the pollution status of particulate matter, the relationship between the gaseous pollutants, physical and chemical properties of single particles, and the profile of water-soluble ions in PM 2.5 during the three episodes. Regional and photochemically aged air masses, which were characterized as having high values of O 3 and SO 2 , were hypothesized to have played a dominant role in the first episode. After mixing local air masses with freshly-emitted primary pollutants, the concentration of NO x continued to increase and the size of SO 4 2– NO 3 − and NH 4 + in the particle population continued to become smaller. The amount of elemental carbon-rich and organic carbon-rich particles in the scaled single particles (0.2–2 μm) and water-soluble K + in PM 2.5 also increased in the episodes. All the available information suggests that the biomass or fuel burning sources in or around Beijing may have had a huge impact on the last two episodes. [ABSTRACT FROM AUTHOR]

An observational study on trace gases and PM 2.5 was conducted at three sites in and around Beijing, during the Olympic season from 2007 to 2009. Air quality improved significantly during the Olympic Games due to the special emission control measures. However, concentrations of the primary pollutants and PM were found to have risen significantly after the Games. Although the major O 3 precursors (NO x and VOCs) were well controlled during the Olympic season, O 3 was still found to be the highest in 2008, based on the data of ground-based observation. All this information suggests that while control of regional emissions for the Beijing Olympic Games did improved the air quality in Beijing, more efforts will be needed for the continuous improvement of regional air quality, especially for significant reductions of O 3 and fine particulate pollution, and not only in Beijing, but also in the Beijing-Tianjin-Hebei region. [ABSTRACT FROM AUTHOR]

O 3 and PM 2.5 were introduced into the newly revised air quality standard system in February 2012, representing a milestone in the history of air pollution control, and China's urban air quality will be evaluated using six factors (SO 2 , NO 2 , O 3 , CO, PM 2.5 and PM 10 ) from the beginning of 2013. To achieve the new air quality standard, it is extremely important to have a primary understanding of the current pollution status in various cities. The spatial and temporal variations of the air pollutants were investigated in 26 pilot cities in China from August 2011 to February 2012, just before the new standard was executed. Hourly averaged SO 2 , NO 2 and PM 10 were observed in 26 cities, and the pollutants O 3 , CO and PM 2.5 were measured in 15 of the 26 cities. The concentrations of SO 2 and CO were much higher in the cities in north China than those in the south. As for O 3 and NO 2 , however, there was no significant difference between northern and southern cities. Fine particles were found to account for a large proportion of airborne particles, with the ratio of PM 2.5 to PM 10 ranging from 55% to 77%. The concentrations of PM 2.5 (57.5 μg/m 3 ) and PM 10 (91.2 μg/m 3 ) were much higher than the values (PM 2.5 : 11.2 μg/m 3 ; PM 10 : 35.6 μg/m 3 ) recommended by the World Health Organization. The attainment of the new urban air quality standard in the investigated cities is decreased by 20% in comparison with the older standard without considering O 3 , CO and PM 2.5 , suggesting a great challenge in urban air quality improvement, and more efforts will to be taken to control air pollution in China. [ABSTRACT FROM AUTHOR]

Background: Renal dysfunction is a serious morbidity in cirrhotic patients with acute upper gastrointestinal bleeding (AUGIB). Terlipressin is the first-line treatment choice for acute variceal bleeding and hepatorenal syndrome (HRS). This study aimed to assess the effect of terlipressin on renal function in patients with liver cirrhosis and AUGIB., Methods: We retrospectively reviewed 40 cirrhotic patients with AUGIB treated with terlipressin by an attending physician between January 2016 and June 2018. We analyzed the change of renal function parameters, including cystatin C (CysC) and creatinine (Cr), during the use of terlipressin and after terlipressin was stopped. We also identified the factors associated with renal function improvement in patients without active bleeding during the use of terlipressin., Results: During the use of terlipressin, CysC value was significantly reduced (1.3±0.8 vs. 1.1±0.7, P=0.001); Cr value was reduced, but the reduction was not statistically significant (68.8±24 vs. 65.5±23, P=0.817); the rate of CysC reduction was significantly higher in patients treated with terlipressin than those treated with somatostatin/octreotide (73.1% vs. 0%, P=0.005); the rate of Cr reduction was not significantly different between patients treated with terlipressin and somatostatin/octreotide (61.5% vs. 20%, P=0.148); no factor associated with CysC reduction was identified; higher hemoglobin, red blood cell, and platelet and lower prothrombin time and international normalized ratio at baseline were significantly associated with Cr reduction. After terlipressin was stopped, neither CysC nor Cr value was significantly reduced (P=0.852 and P=0.296)., Conclusions: Terlipressin may be beneficial on preventing renal function impairment in cirrhotic patients with AUGIB., Competing Interests: Conflicts of Interest: The authors have no conflict of interest to declare., (2020 Annals of Translational Medicine. All rights reserved.)

Germination of Bacillus subtilis spores is normally initiated when nutrients from the environment interact with germinant receptors (GRs) in the spores' inner membrane (IM), in which most of the lipids are immobile. GRs and another germination protein, GerD, colocalize in the IM of dormant spores in a small focus termed the "germinosome," and this colocalization or focus formation is dependent upon GerD, which is also essential for rapid GR-dependent spore germination. To determine the fate of the germinosome and germination proteins during spore germination and outgrowth, we employed differential interference microscopy and epifluorescence microscopy to track germinating spores with fluorescent fusions to germination proteins and used Western blot analyses to measure germination protein levels. We found that after initiation of spore germination, the germinosome foci ultimately changed into larger disperse patterns, with ≥ 75% of spore populations displaying this pattern in spores germinated for 1 h, although >80% of spores germinated for 30 min retained the germinosome foci. Western blot analysis revealed that levels of GR proteins and the SpoVA proteins essential for dipicolinic acid release changed minimally during this period, although GerD levels decreased ∼ 50% within 15 min in germinated spores. Since the dispersion of the germinosome during germination was slower than the decrease in GerD levels, either germinosome stability is not compromised by ∼ 2-fold decreases in GerD levels or other factors, such as restoration of rapid IM lipid mobility, are also significant in germinosome dispersion as spore germination proceeds., (Copyright © 2015, American Society for Microbiology. All Rights Reserved.)