This study evaluates the aging timescale and the cloud condensation nuclei (CCN) activity of black carbon (BC) over East Asia and its outflow region using a size‐ and mixing‐state‐resolved ...three‐dimensional model, the Weather Research and Forecasting model with chemistry (WRF‐chem) with the Aerosol Two‐dimensional bin module for foRmation and Aging Simulation (ATRAS) and the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC). The WRF‐chem/ATRAS‐MOSAIC model explicitly calculates BC aging (condensation and coagulation) and removal processes, with 12 size and 10 BC mixing state bins (128 bins in total). The model reveals large spatial and temporal variability of the BC aging timescale and the CCN activity of BC‐containing particles over East Asia (spring 2009) with their strong size and supersaturation dependence. The BC aging timescale differs from 0.19 to 3.1 days (period and domain average at an altitude of 1 km), depending on the choice of size (mass or number) and supersaturation (1.0% or 0.1%). As a result, almost 100% of BC‐containing particles are CCN‐active at a supersaturation of 1.0%, whereas 20–50% of BC‐containing particles are CCN‐inactive at a supersaturation of 0.1%, with a strong size dependence. These results show the importance of resolving BC aging processes and their dependence on size and supersaturation in models for more accurate simulations of BC concentrations and their distribution and lifetime. A sensitivity simulation without resolving BC mixing state shows the underestimation of total BC mass concentrations by 5–10% and the BC mass concentrations in the CCN‐inactive particles (at a supersaturation of 0.1%) by 40–60% over the outflow region (at 150°E), compared with the simulation resolving BC mixing state. Because BC aging speed is very slow at 150°E and eastward, the change in BC mass and its CCN activity by resolving BC mixing state will continue over long distances and may have a large impact on BC transport from East Asia to remote regions such as North America and the Arctic.
Key Points
Simulation of the aging timescale and CCN activity of BC by a 2‐D aerosol bin model (12 × 10 bins)
These BC parameters are shown three dimensionally with the large size/supersaturation dependence
Importance of resolving BC mixing state for simulations of BC and its CCN activity is shown
This study quantifies how uncertainties in the size distribution and mixing state parameters of black carbon (BC) emissions translate into the uncertainties in BC radiative effects by using a ...particle‐size‐ and mixing‐state‐resolved three‐dimensional model, the Weather Research and Forecasting model with chemistry (WRF‐chem) with the Aerosol Two‐dimensional bin module for foRmation and Aging Simulation (ATRAS) and the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC). The WRF‐chem/ATRAS‐MOSAIC model can explicitly calculate BC processes in the atmosphere, such as BC aging due to condensation and coagulation and the resulting enhancement of absorption and cloud condensation nuclei activity, with 12 size and 10 BC mixing state bins (128 bins in total). Fifteen model simulations perturbing the emission parameters within their uncertainties are conducted over East Asia (spring 2009) to understand which parameters and processes are important and which are associated with the uncertainty in evaluating BC radiative effects. The simulations reveal a large variability (uncertainty) of BC optical and radiative variables over the East Asian region (the variability is 58–99%), which corresponds to ranges of BC radiative effect of 1.6–2.8 W m−2 at the top of the atmosphere and from −5.2 to −2.1 W m−2 at the surface over East Asia. BC optical and radiative variables are 3 to 5 times sensitive to the size and the mixing state in emissions than BC mass concentrations (the variability is 20%). The two main causes of the difference in sensitivity are the reduction of the variability of BC mass concentrations by coagulation and the enhancement of the variability of BC absorption by resolving BC mixing state. These complicated responses of aerosol processes can be calculated for the first time using a detailed aerosol model such as ATRAS. The results suggest that the following two points are important in the estimation of BC radiative effects: (1) reduction of the uncertainties in the aerosol size distribution and mixing state in emissions and (2) improvement of the representation of BC mixing state and absorption enhancement in aerosol models because most models do not treat them sufficiently.
Key Points
The simulations reveal a large uncertainty of BC radiative effects due to the treatment of emissions
BC radiative effects are 3–5 times more sensitive to emission parameters than BC mass concentrations
The results show the importance of resolving BC mixing state and absorption enhancement in models
This study develops an aerosol module, the Aerosol Two‐dimensional bin module for foRmation and Aging Simulation version 2 (ATRAS2), and implements the module into a global climate model, Community ...Atmosphere Model. The ATRAS2 module uses a two‐dimensional (2‐D) sectional representation with 12 size bins for particles from 1 nm to 10 μm in dry diameter and 8 black carbon (BC) mixing state bins. The module can explicitly calculate the enhancement of absorption and cloud condensation nuclei activity of BC‐containing particles by aging processes. The ATRAS2 module is an extension of a 2‐D sectional aerosol module ATRAS used in our previous studies within a framework of a regional three‐dimensional model. Compared with ATRAS, the computational cost of the aerosol module is reduced by more than a factor of 10 by simplifying the treatment of aerosol processes and 2‐D sectional representation, while maintaining good accuracy of aerosol parameters in the simulations. Aerosol processes are simplified for condensation of sulfate, ammonium, and nitrate, organic aerosol formation, coagulation, and new particle formation processes, and box model simulations show that these simplifications do not substantially change the predicted aerosol number and mass concentrations and their mixing states. The 2‐D sectional representation is simplified (the number of advected species is reduced) primarily by the treatment of chemical compositions using two interactive bin representations. The simplifications do not change the accuracy of global aerosol simulations. In part 2, comparisons with measurements and the results focused on aerosol processes such as BC aging processes are shown.
Key Points
A 2‐D sectional global aerosol model ATRAS2, which resolves both particle size (12 bins) and BC mixing state (8 bins), is developed
The computational cost of the module is reduced by more than a factor of 10 by some simplifications compared with our previous module
The simplifications of both aerosol processes and 2‐D sectional representation do not change the accuracy of global aerosol simulations
Background
Improving patients' oral hygiene is an option for preventing postoperative pneumonia that may be caused by aspiration of oral and pharyngeal secretions. Whether preoperative oral care by a ...dentist can decrease postoperative complications remains controversial. A retrospective cohort study was undertaken to assess the association between preoperative oral care and postoperative complications among patients who underwent major cancer surgery.
Methods
The nationwide administrative claims database in Japan was analysed. Patients were identified who underwent resection of head and neck, oesophageal, gastric, colorectal, lung or liver cancer between May 2012 and December 2015. The primary outcomes were postoperative pneumonia and all‐cause mortality within 30 days of surgery. Patient background was adjusted for with inverse probability of treatment weighting using propensity scoring.
Results
Of 509 179 patients studied, 81 632 (16·0 per cent) received preoperative oral care from a dentist. A total of 15 724 patients (3·09 per cent) had postoperative pneumonia and 1734 (0·34 per cent) died within 30 days of surgery. After adjustment for potential confounding factors, preoperative oral care by a dentist was significantly associated with a decrease in postoperative pneumonia (3·28 versus 3·76 per cent; risk difference − 0·48 (95 per cent c.i. −0·64 to−0·32) per cent) and all‐cause mortality within 30 days of surgery (0·30 versus 0·42 per cent; risk difference − 0·12 (−0·17 to −0·07) per cent).
Conclusion
Preoperative oral care by a dentist significantly reduced postoperative complications in patients who underwent cancer surgery.
Preoperative dental care reduces postoperative pneumonia
War Is All Hell Blum, Edward J; Matsui, John H
2021, 2021-05-28
eBook
During his first inaugural address, Abraham Lincoln expressed hope that the "better angels of our nature" would prevail as war loomed. He was wrong. The better angels did not, but for many Americans, ...the evil ones did. War Is All Hell peers into the world of devils, demons, Satan, and hell during the era of the American Civil War. It charts how African Americans and abolitionists compared slavery to hell, how Unionists rendered Confederate secession illegal by linking it to Satan, and how many Civil War soldiers came to understand themselves as living in hellish circumstances. War Is All Hell also examines how many Americans used evil to advance their own agendas. Sometimes literally, oftentimes figuratively, the agents of hell and hell itself became central means for many Americans to understand themselves and those around them, to legitimate their viewpoints and actions, and to challenge those of others. Many who opposed emancipation did so by casting Abraham Lincoln as the devil incarnate. Those who wished to pursue harsher war measures encouraged their soldiers to "fight like devils." And finally, after the war, when white men desired to stop genuine justice, they terrorized African Americans by dressing up as demons.A combination of religious, political, cultural, and military history, War Is All Hell illuminates why, after the war, one of its leading generals described it as "all hell."
Tissue development and homeostasis are governed by the actions of stem cells. Multipotent cells are capable of self-renewal during the course of one's lifetime. The accurate and appropriate ...regulation of stem cell functions is absolutely critical for normal biological activity. Several key developmental or signaling pathways have been shown to play essential roles in this regulatory capacity. Specifically, the Janus-activated kinase/signal transducer and activator of transcription, Hedgehog, Wnt, Notch, phosphatidylinositol 3-kinase/phosphatase and tensin homolog, and nuclear factor-κB signaling pathways have all been shown experimentally to mediate various stem cell properties, such as self-renewal, cell fate decisions, survival, proliferation, and differentiation. Unsurprisingly, many of these crucial signaling pathways are dysregulated in cancer. Growing evidence suggests that overactive or abnormal signaling within and among these pathways may contribute to the survival of cancer stem cells (CSCs). CSCs are a relatively rare population of cancer cells capable of self-renewal, differentiation, and generation of serially transplantable heterogeneous tumors of several types of cancer.
Summary
Background
The association between antithrombin use and mortality in patients with sepsis‐associated disseminated intravascular coagulation (DIC) remains controversial.
Objectives
To examine ...the hypothesis that antithrombin could be effective in the treatment of patients with sepsis‐associated DIC following severe pneumonia.
Methods
Propensity score and instrumental variable analyses were performed by use of a nationwide administrative database, the Japanese Diagnosis Procedure Combination inpatient database. The main outcome was 28‐day mortality.
Results
Severe pneumonia patients diagnosed with sepsis‐associated DIC (n = 9075) were categorized into antithrombin (n = 2663) and control (n = 6412) groups. Propensity score matching created a matched cohort of 2194 pairs of patients with and without antithrombin use. Mortality differences were found between the two groups (antithrombin vs. control: unmatched, 40.8% vs. 45.7%; propensity‐matched, 40.6% vs. 44.2%; inverse probability‐weighted, 41.1% vs. 45.1%). Multiple logistic regression analyses showed an association between antithrombin use and 28‐day mortality (unmatched with propensity score adjusted, adjusted odds ratio OR 0.87, 95% confidence interval CI 0.78–0.97; propensity‐matched, adjusted OR 0.85, 95% CI 0.75–0.97; inverse probability‐weighted, adjusted OR 0.85, 95% CI 0.79–0.90). An analysis with the hospital antithrombin‐prescribing rate as an instrumental variable showed that receipt of antithrombin was associated with a 9.9% (95% CI 3.5–16.3) reduction in 28‐day mortality.
Conclusions
This retrospective, large, nationwide database study demonstrates that antithrombin administration may be associated with reduced 28‐day mortality in patients with severe pneumonia and sepsis‐associated DIC. A large, multinational randomized trial is required.
Global aerosol simulations are conducted by using the Community Atmosphere Model version 5 with the Aerosol Two‐dimensional bin module for foRmation and Aging Simulation version 2 (CAM5‐chem/ATRAS2) ...which was developed in part 1. The model uses a two‐dimensional (2‐D) section representation with 12 size bins from 1 nm to 10 μm and 8 black carbon (BC) mixing state bins, and it can calculate detailed aerosol processes and their interactions with radiation and clouds. The simulations have similar or better agreement with aerosol observations (e.g., aerosol optical depth, absorption aerosol optical depth (AAOD), aerosol number concentrations, mass concentrations of each species) compared with the simulations using the Modal Aerosol Model with three modes. Sensitivity simulations show that global mean AAOD is reduced by 15% by resolving BC mixing state as a result of two competing effects (optical and lifetime effects). AAOD is reduced by 10–50% at low and midlatitudes in the 2‐D sectional simulation because BC absorption enhancement by coating species is reduced by resolving pure BC, thinly coated BC, and BC‐free particles in the model (optical effect). In contrast, AAOD is enhanced by 5–30% at high‐latitudes because BC concentrations are enhanced by 40–200% over the regions by resolving less CCN active particles (lifetime effect). The simulations also suggest a model which resolves more than 3 BC categories (including BC‐free particles) is desirable to calculate the optical and lifetime effects accurately. The complexity of aerosol representation is shown to be especially important for simulations of BC and CCN concentrations and AAOD.
Key Points
Simulations of a 2‐D sectional global aerosol model (CAM5‐chem/ATRAS2) have reasonable agreements with various aerosol measurements
AAOD is enhanced or reduced regionally (5–50%) by improving the representation of optical and lifetime effects of BC mixing state
The complexity of aerosol representation (mixing state and composition) is important for simulations of BC, AAOD, and CCN concentrations
Abstract
Background
The aim of this study was to compare perioperative outcomes of urgent colectomy and placement of a self-expanding metallic stent followed by colectomy for patients with malignant ...right colonic obstruction. Right-sided malignant obstruction is less common than left-sided. Stenting for malignant left colonic obstruction has been reported to reduce postoperative complications. However, the impact of stenting for malignant right colonic obstruction remains undefined.
Methods
The study included patients with right-sided malignant obstruction or stenosis undergoing colectomy between April 2012 and March 2017 identified from a nationwide database. Propensity score matching analysis was used to compare mortality and morbidity rates, proportion receiving a stoma and postoperative stay between urgent colectomy and stent groups.
Results
From 9572 patients, 1500 pairs were generated by propensity score matching. There was no significant difference in in-hospital mortality between the urgent colostomy and stent groups (1·6 versus 0·9 per cent respectively; P = 0·069). Complications were more common after urgent colectomy than stenting (22·1 versus 19·1 per cent; P = 0·042). Surgical-site infection was more likely with urgent colectomy (7·1 versus 4·4 per cent; P = 0·001). There was no significant difference between the two groups in anastomotic leakage (3·8 versus 2·6 per cent; P = 0·062). The proportion of patients needing a stoma was higher with urgent colectomy than primary treatment with stents (5·1 versus 1·7 per cent; P < 0·001). Postoperative stay was longer after urgent colectomy (15 versus 13 days; P < 0·001).
Conclusion
Stenting followed by colectomy in patients with malignant right colonic obstruction may provide more favourable perioperative outcomes than urgent colectomy.
Graphical Abstract
Propensity score matching analysis of 1500 pairs of patients with malignant right colonic obstruction demonstrated that placement of a self-expanding metallic stent followed by colectomy provided patients with favourable outcomes compared with urgent colectomy, in terms of lower rates of morbidity and stoma construction, and shorter postoperative hospital stay.
Graphical Abstract
Primary stenting more favourable
In nature, biological nanomaterials are synthesized under ambient conditions in a natural microscopic‐sized laboratory, such as a cell. Biological molecules, such as peptides and proteins, undergo ...self‐assembly processes in vivo and in vitro, and these monomers are assembled into various nanometer‐scale structures at room temperature and atmospheric pressure. The self‐assembled peptide nanostructures can be further organized to form nanowires, nanotubes, and nanoparticles via their molecular‐recognition functions. The application of molecular self‐assemblies of synthetic peptides as nanometer‐scale building blocks in devices is robust, practical, and affordable due to their advantages of reproducibility, large‐scale production ability, monodispersity, and simpler experimental methods. It is also beneficial that smart functionalities can be added at desired positions in peptide nanotubes through well‐established chemical and peptide syntheses. These features of peptide‐based nanotubes are the driving force for investigating and developing peptide nanotube assemblies for biological and non‐biological applications.
The current status of research into peptide nanotubes is discussed. The configurations of potential nanodevices are illustrated, for example, by means of biological recognition between functionalized protein nanotubes and complementary protein‐patterned surfaces (see Figure). Extension of research efforts from pure structural aspects of bionanotubes to successful use in functional device applications is shown.
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