Tolerance Factor and Cooperative Tilting Effects in Vacancy-Ordered Double Perovskite Halides
Abstract not provided
Maughan, Annalise E.↗
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Nucleon form factors in dispersively improved chiral effective field theory: Scalar form factor
We propose a method for calculating the nucleon form factors (FFs) of $G$-parity-even operators by combining Chiral Effective Field Theory ($\chi$EFT) and dispersion analysis. The FFs are expressed as dispersive integrals over the two-pion cut at $t > 4 M_\pi^2$. The spectral functions are obtained from the elastic unitarity condition and expressed as products of the complex $\pi\pi \rightarrow N\bar N$ partial-wave amplitudes and the timelike pion FF. $\chi$EFT is used to calculate the ratio of the partial-wave amplitudes and the pion FF, which is real and free of $\pi\pi$ rescattering in the $t$-channel ($N/D$ method). The rescattering effects are then incorporated by multiplying with the squared modulus of the empirical pion FF. The procedure results in a marked improvement compared to conventional $\chi$EFT calculations of the spectral functions. We apply the method to the nucleon scalar FF and compute the scalar spectral function, the scalar radius, the $t$-dependent FF, and the Cheng-Dashen discrepancy. Higher-order chiral corrections are estimated through the $\pi N$ low-energy constants. Results are in excellent agreement with dispersion-theoretical calculations. We elaborate several other interesting aspects of our method. The results show proper scaling behavior in the large-$N_c$ limit of QCD because the $\chi$EFT includes $N$ and $\Delta$ intermediate states. The squared modulus of the timelike pion FF required by our method can be extracted from Lattice QCD calculations of vacuum correlation functions of the operator at large Euclidean distances. Our method can be applied to the nucleon FFs of other operators of interest, such as the isovector-vector current, the energy-momentum tensor, and twist-2 QCD operators (moments of generalized parton distributions).
1=Nc expansion↗
Effect of Saccharide and Alditol Additives on Uniaxial Tensile Behavior of Gellan Films
The uniaxial tensile behavior of gellan films containing saccharides or alditols was examined to elucidate the plasticizing effect of these additives. Five saccharides as well as two alditols were used. The films were tested after removal of water as far as possible. The tensile modulus decreased as the content of the additives increased, suggesting apparent plasticizing effect of the additives. The plasticizing effect was discussed referring the glass transition temperature instead of the melting point of the additives, assuming the additives were in the “supercooled” liquid state even below the melting point. Since some additives showed similar values of tensile modulus regardless of whether the additive was in the solid state or in the liquid state, a blending law of the moduli was proposed to explain the apparent plasticizing effect. On the other hand, it was found that xylitol and two monosaccharides glucose and fructose acted as true plasticizers. The effective factor was attributed to the solubility of these additives to the gellan matrix. A relationship between the profile of the stress–strain curve and the plasticizing effect was also proposed.
36 MATERIALS SCIENCE↗
Composite nanofibers for highly efficient photocatalytic degradation of organic dyes from contaminated water
In this study highly efficient photocatalyst based on composite nanofibers containing polyacrylonitrile (PAN), carbon nanotubes (CNT), and surface functionalized TiO{sub 2} nanoparticles was developed. The composite nanofibers were fabricated using electrospinning technique followed by chemical crosslinking. The surface modification and morphology changes of the fabricated composite nanofibers were examined through SEM, TEM, and FTIR analysis. The photocatalytic performance of the composite nanofibers for the degradation of model molecules, methylene blue and indigo carmine, under UV irradiation in aqueous solutions was investigated. The results demonstrated that high photodegradation efficiency was obtained in a short time and at low power intensity compared to other reported studies. The effective factors on the degradation of the dyes, such as the amount of catalyst, solution pH and irradiation time were investigated. The experimental kinetic data were fitted using pseudo-first order model. The effect of the composite nanofibers as individual components on the degradation efficiency of MB and IC was evaluated in order to understand the overall photodegradation mechanism. The results obtained showed that all the components possess significant effect on the photodegradation activity of the composite nanofibers. The stability studies demonstrated that the photodegradation efficiency can remain constant at the level of 99% after five consecutive cycles. - Highlights: • Develop effective photocatalyst based on PAN–CNT/TiO{sub 2}–NH{sub 2} composite nanofibers. • High photodegradation efficiency and fast kinetics was obtained. • Regeneration of the composite nanofibers allowed the reuse of these material. • Mechanism of the photocatalytic degradation was proposed. • The flexibility of the composite nanofibers allows use in a continuous operation mode.
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
Gasification Characteristics of Coal/Biomass Mixed Fuels
A research project was undertaken that had the overall objective of developing the models needed to accurately predict conversion rates of coal/biomass mixtures to synthesis gas under conditions relevant to a commercially-available coal gasification system configured to co-produce electric power as well as chemicals and liquid fuels. In our efforts to accomplish this goal, experiments were performed in an entrained flow reactor in order to produce coal and biomass chars at high heating rates and temperatures, typical of the heating rates and temperatures fuel particles experience in real systems. Mixed chars derived from coal/biomass mixtures containing up to 50% biomass and the chars of the pure coal and biomass components were subjected to a matrix of reactivity tests in a pressurized thermogravimetric analyzer (TGA) in order to obtain data on mass loss rates as functions of gas temperature, pressure and composition as well as to obtain information on the variations in mass specific surface area during char conversion under kinetically-limited conditions. The experimental data were used as targets when determining the unknown parameters in the chemical reactivity and specific surface area models developed. These parameters included rate coefficients for the reactions in the reaction mechanism, enthalpies of formation and absolute entropies of adsorbed species formed on the carbonaceous surfaces, and pore structure coefficients in the model used to describe how the mass specific surface area of the char varies with conversion. So that the reactivity models can be used at high temperatures when mass transport processes impact char conversion rates, Thiele modulus – effectiveness factor relations were also derived for the reaction mechanisms developed. In addition, the reactivity model and a mode of conversion model were combined in a char-particle gasification model that includes the effects of chemical reaction and diffusion of reactive gases through particle pores and energy exchange between the particle and its environment. This char-particle gasification model is capable of predicting the average mass loss rates, sizes, apparent densities, specific surface areas, and temperatures of the char particles produced when co-firing coal and biomass to the type environments established in entrained flow gasifiers operating at high temperatures and elevated pressures.
01 COAL, LIGNITE, AND PEAT↗
Development of a Severe Accident Analysis Engine Using Approximate Reasoning
In hypothetical severe accident scenarios, nuclear power plant safety is challenged by core degradation and release of fission products. To aid the plant operator and technical support center staff, research has been performed to develop understanding of severe accident phenomenology, assessing their risk and devise measures to mitigate accident consequences (Sehgal, 2011). Nuclear power plant accidents involve highly complex physical and chemical interactions, a large number of safety related systems, and emergency operating procedures (EOP) and severe accident management guidelines (SAMG). Large number of factors with uncertainty and stress can overwhelm the operators. The overall objective of the present research is to develop a methodology and tools that an operator can use to predict severe accident progression and make effective decisions to arrest and manage the accident under large uncertainties. Towards this goal, this study examines a novel approach that brings to bear a combined use of techniques in artificial intelligence (Russel and Norvig, 2010), including Bayesian Network (BN), Answer Set Programming (ASP) and Fuzzy Inference (FI) to achieve faster-than-real-time, yet sufficiently accurate analysis of severe accident progression. Bayesian network (BN) is a type of probabilistic graphical models that can be used to represent knowledge and conditional dependencies about an uncertain realm. It is useful for capturing the causal relationships in a complex system. It also allows prediction via Bayesian inference (Kelly and Smith, 2012). It is composed of nodes and edges, which express random variables and probabilistic relationships between the nodes, respectively. This relationship, given by conditional probability is calculated using stochastic methods. The BN is used in several systems for analysis and management of accident risk; e.g. (Knochenhauer and Frid, 2010). In those systems, the nodes or so-called 'effective factors' are presumably known within the network by system descriptions in SAMGs. There are two steps to configure the BN, namely (i) identifying compositions within the network and (ii) defining conditional dependency between nodes. The first step is performed following the spirit of ASP (Baral, 2003) using Prolog (Wielemaker, 2005). Knowledge representation is used to build databases required for processing by ASP. Knowledge representation is defined as the expression of knowledge in a way that is understandable to both human and computers. Originally knowledge indicates data, information and facts. To focus, knowledge should be formed to achieve a goal. In a severe accident, key physics and safety related components status are defined according to a failure mode. The conditional dependencies between nodes are generated by approximate reasoning using Fuzzy inference (Zadeh, 1995). Fuzzy logic is a multiple-valued logic to treat ambiguous features such as linguistic description. It indicates possibility, which is distinguished from probability. Fuzzy set consists of linguistic variables according to the fixed rule. In other words, even uncertain states could be expressed as not binary logic, but as many-value logic by rule-based technology. Fuzzy control system is comprised of Fuzzy inference engine that is performed based on the 'If-Then Rule'. The 'If-Then Rule' is of the following form. If Y1 is B11 and Y2 is B12 then Z is C1. If Y1 is B21 and Y2 is B22 then Z is C2. Y1 and Y2 are inputs, which indicate conditional variables. Z indicates decision-making and both B and C are linguistic variables. With this rule-based technique, the approximate reasoning can be realized by Fuzzy inference. (authors)
22 GENERAL STUDIES OF NUCLEAR REACTORS↗
A New Directional Canopy Emissivity Model Based on Spectral Invariants
A new directional canopy emissivity model (CE-P) based on spectral invariants is proposed in this study. First, we prove the existence of the spectral invariant properties in the thermal infrared (TIR) band using a Monte Carlo model. Based on it, the equation of the new model is derived from the perspective of absorption. In this expression, single-scattering and multiscattering effects are separated analytically in the TIR band. We find that the overall contribution of multiple scatterings is less than 0.005 when the component emissivities are over 0.90, and the overall contribution decreases with increasing leaf or soil emissivity. Furthermore, the new model can avoid the logical difficulty encountered when using the traditional cavity effect factor to simulate the emissivity of a sparse vegetation canopy. The results of 4SAIL and Discrete Anisotropic Radiative Transfer (DART) are selected to do cross validation. The CE-P can achieve a high accuracy compared with 4SAIL and DART, with an absolute bias less than 0.002 when the leaf (soil) emissivity is equal to 0.98 (0.94). Four widely used analytical models are selected for comparison. The resulting accuracies of these models are ordered from CE-P to REN15, FR97, FR02, and VALOR96 with the most serious error up to 0.002, 0.002, 0.007, 0.013, and 0.014, respectively. Finally, three main conclusions are obtained through the sensitivity analysis: the multiscattering between vegetation and the background can be ignored when the leaf (soil) emissivity is no less than 0.94 (0.90), the second and higher order scattering within the vegetation can also be ignored when the leaf (soil) emissivity is no less than 0.94 (0.90), and the single-scattering effect within the canopy should be considered which can be calculated using three view factors.
58 GEOSCIENCES↗
Simulated effect of edge plasma density parameters on lower hybrid wave scattering in EAST
The incorporation of lower hybrid (LH) wave spectrum broadening in the poloidal wavenumber (k θ ) space at the last close field surface (LCFS) is reported to lead to better agreement of the modeled LH wave current profile with the experimental results [Baek et al., Nucl. Fusion 61, 106034 (2021)]. To further understand its underlying mechanism and find the possible influence factors, effects of wave scattering caused by drift-wave type density fluctuation on the probability distribution of the LH wave polar refractive index (N θ ) at the LCFS are studied under density parameters in the scrape-off-layer. According to a scattering model [P. T. Bonoli and E. Ott, Phys Fluids 25(2), 359–375 (1982)], scattering probability and scattering angle distribution are two main factors that determine the degree of spectral broadening. Studies presented here show that the total scattering probability increases first and then decreases as the wave propagates toward a smaller normalized radius of poloidal magnetic flux (ρ). The degree of spectral broadening is found to depend on the density and density fluctuation together by changing the intensity and a proportion of the geometrical optics approximation term and the E×B drift term in the scattering model. Additionally, the fluctuation correlation length can significantly modify the probability distribution of N θ at the LCFS, which is found to significantly change the LH wave current profile.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
On the radar cross section (RCS) prediction of vehicles moving on the ground
As readers should be aware, Radar Cross Section depends on the factors such as: Wave frequency and polarization, Target dimension, angle of ray incidence, Target’s material and covering, Type of radar system as monostatic or bistatic, space in which contains target and propagating waves, and etc. Having moved or stationed in vehicles can be effective in RCS values. Here, we investigate effective factors in RCS of moving targets on the ground or sea. Image theory in electromagnetic applies to be taken into account RCS of a target over the ground or sea.
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
Supporting cost-effective watershed management strategies for Chesapeake Bay using a modeling and optimization framework
Extensive efforts to adaptively manage nutrient pollution rely on Chesapeake Bay Program’s (Phase 6) Watershed Model, called Chesapeake Assessment Scenario Tool (CAST), which helps decision-makers plan and track implementation of Best Management Practices (BMPs). We describe mathematical characteristics of CAST and develop a constrained nonlinear BMP-subset model, software, and visualization framework. This represents the first publicly available optimization framework for exploring least-cost strategies of pollutant load control for the United States’ largest estuary. The optimization identifies implementation options for a BMP subset modeled with load reduction effectiveness factors, and the web interface facilitates interactive exploration of >30,000 solutions organized by objective, nutrient control level, and for ~200 counties. We assess framework performance and demonstrate modeled cost improvements when comparing optimization-suggested proposals with proposals inspired by jurisdiction plans. Stakeholder feedback highlights the framework’s current utility for investigating cost-effective tradeoffs and its usefulness as a foundation for future analysis of restoration strategies.
54 ENVIRONMENTAL SCIENCES↗
The increase in animal mortality risk following exposure to sparsely ionizing radiation is not linear quadratic with dose
The US government regulates allowable radiation exposures relying, in large part, on the seventh report from the committee to estimate the Biological Effect of Ionizing Radiation (BEIR VII), which estimated that most contemporary exposures- protracted or low-dose, carry 1.5 fold less risk of carcinogenesis and mortality per Gy than acute exposures of atomic bomb survivors. This correction is known as the dose and dose rate effectiveness factor for the life span study of atomic bomb survivors (DDREF LSS ). As a result, it was calculated by applying a linear-quadratic dose response model to data from Japanese atomic bomb survivors and a limited number of animal studies.
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTAN↗
SU-G-TeP2-03: Comparison of Standard Dosimetry Protocol in Japan and AAPM TG-51 Addendum in Order to Establish Optimal Dosimetry for FFF Beam
Purpose: Japan Standard Dosimetry of Absorbed dose to water in external beam radiotherapy (JSDP12) is widely used to measure radiation dose in radiotherapy. However, JSDP12 does not take flattening-filter-free (FFF) beam into consideration. In addition, JSDP12 applied TPR20,10 for dose quality index for photon beam. The purpose of this study is to compare JSDP12 with AAPM TG-51 addendum in order to establish optimal dosimetry procedure for FFF beam. Method: We evaluated the ion-recombination factor (ks) and the correction factor of radial beam profile (Prp) in FFF beam dosimetry. The ks was introduced by 2 voltages method and verified by Jaffe’s plot. The Prp was given by both film measurement and calculation of treatment planning system, and compared them. Next, we compared the dose quality indexes (kQ) between TPR20,10 method and PDD(10)x method. Finally we considered optimal dosimetry protocol for FFF photon beam using JSDP12 with referring TG-51 addendum protocols. The FFF photon beams of 6 MV (6X-FFF) and 10 MV (10X-FFF) from TrueBeam were investigated in this study. Results: The ks for 6X-FFF and 10X-FFF beams were 1.005 and 1.010, respectively. The Prp of 0.6 cc ionization chamber for 6X-FFF and 10X-FFF beams (Film, TPS) were (1.004, 1.008) and (1.005, 1.008), respectively. The kQ for 6X-FFF and 10X-FFF beams (JSDP12, TG-51 addendum) were (0.9950, 0.9947) and (0.9851, 0.9845), respectively. The most effective factor for uncertainty in FFF photon beam measurement was Prp for JSDP12 formalism. Total dosimetric differences between JSDP12 and TG-51 addendum for 6X-FFF and 10X-FFF were -0.47% and -0.73%, respectively. Conclusion: The total dosimetric difference between JSDP12 and TG-51 addendum was within 1%. The introduction of kQ given by JSDP is feasible for FFF photon beam dosimetry. However, we think Prp should be considered for optimal dosimetry procedure even if JSDP12 is used for FFF photon beam dosimetry.
61 RADIATION PROTECTION AND DOSIMETRY↗
Estimated External Doses to Members of the Public from Patients with {sup 131}I Treatment - Paper 143
To protect individuals from the radiation emitted by a patient receiving {sup 131}I treatment a licensee must estimate the maximum likely effective dose to members of the public. Under current guidance by the United States Nuclear Regulatory Commission (NRC), a licensee may authorize the release of the patient if the effective dose is unlikely to exceed 5 mSv. NRC provides guidance to its licensees, in NRC Regulatory Guide 8.39, on acceptable methods that may be used to calculate the dose to a member of the public that may result from releasing the patient. To further assist licensees in implementing the regulation, NRC used conservative assumptions to estimate the activity of radionuclide in a patient, and the dose rate at 1 meter from the patient, that would be indicators of a potential dose to a member of the public of 5 mSv. Licensees may use these tables as operational criteria for releasing a patient if the conservative assumptions are considered acceptable. Licensees may also perform their own calculations, using case-specific assumptions, to show compliance with 5 mSv release criterion. The scope of this work is to provide dose coefficients for a variety of plausible public exposure scenarios that could be used by licensees to to show compliance. In the patient-specific calculations, the licensee is free to consider factors such as occupancy factor, effective half-life of the radionuclide in the patient's body, and tissue shielding. A conservative method of calculating the maximum likely dose to members of the public is provided in NRC Reg. Guide 8.39, which assumes no tissue attenuation of by the patient's body, no biological component that reduces the effective half-life of the radionuclide, and the patient's body burden is a point source. The assumption of no biological removal from the body introduces some conservatism into dose estimates for {sup 131}I. Also, it has been shown that the assumption of a point source with no tissue attenuation substantially overestimates the dose rate to nearby persons. The current method for calculating the maximum dose rate to members of the public from a nuclear medicine patient provided in US-NRC Regulatory Guide 8.39 assumes the patient's body burden is a point-source. Lack of consideration of tissue attenuation by the patient's body and biological removal of the radionuclide leads to a substantial overestimate of the actual external dose rate to a nearby member of the public. However, use of these assumptions in estimating potential dose to a member of the public simplifies the calculations considerably and, although generally conservative, the calculations serve as a useful screening tool. Many, if not most patients, could be released on that basis. If not, then refined calculations may be used, and the coefficients described in this paper provide one of the means for refining the calculations in cases where the screening calculations were not adequate. (authors)
61 RADIATION PROTECTION AND DOSIMETRY↗
Epidemiologic Study of One Million U.S. Radiation Workers and Veterans
The single most important question in radiation epidemiology is determining the level of health risks associated with radiation exposures that occur gradually over time. The study of one million early U.S. radiation workers and veterans has been designed to provide information on risk following chronic exposures by focusing on occupational groups with differing radiation exposure patterns, including intakes of radionuclides. The cost-efficient study builds on the investments made and foundations laid by investigators and government agencies over the past 30-40 years, which have established early worker cohorts that can now provide answers to questions on the lifetime human health risks associated with low-level radiation exposures. Within the overall goal of the epidemiologic study of one million U.S. radiation workers and veterans, this project had a total of nine specific aims which included studies of six populations for multiple endpoints including cancer overall mortality, leukemia and non-cancer mortality. The six populations included: Mound, Ohio, workers exposed to polonium, tritium and plutonium; nuclear power plant workers within the Landauer dosimetry and Nuclear Regulatory Commission data files; industrial radiographers; Mallinckrodt uranium workers; uranium workers who linked with the US Renal Data System; and nuclear weapons test participants. Over 400,000 workers and atomic veterans are included in these populations, with vital status being determined and analyses of all causes of death undertaken. A critical, integral component of the studies has been comprehensive evaluations of dosimetry involving, in many cases, complex dose reconstructions, and assessments of uncertainties. The work has also involved development of state-of-the art statistical approaches and modeling. All nine aims were accomplished successfully, resulting in publication of two NCRP documents, 13 literature papers, numerous Boice Reports in Health Physics News and many presentations of the work at scientific meetings. Furthermore, recommendations have been developed for an approach to integrate epidemiologic observations with radiation biology for risk assessment and biological models of radiation effect. The results of this project, as well as ongoing epidemiology studies of US radiation workers and veterans, are providing much-needed insights into complex issues regarding cancer and non-cancer health risks from low dose irradiation, how to apply a "dose and dose rate effectiveness factor" to scale the risks from the A-bomb survivor data to current occupational and environmental circumstances, and how to evaluate risk following intakes of radioactive substances. In addition to application to radiation workers, the results of the studies can provide guidance as society debates the role of nuclear energy and deals with nuclear waste, threats of terrorist attacks with nuclear/radiological devices, the remarkable increase in medical exposures to CT scans and nuclear imaging, and to NASA as radiation protection for astronauts on long-duration mission beyond low-Earth orbit is planned.
61 RADIATION PROTECTION AND DOSIMETRY↗
Graphical methods for evaluating covering arrays
Covering arrays relax the condition of orthogonal arrays by only requiring that all combination of levels be covered but not requiring that the appearance of all combination of levels be balanced. This allows for a much larger number of factors to be simultaneously considered but at the cost of poorer estimation of the factor effects. To better understand patterns between sets of columns and evaluate the degree of coverage to compare and select between alternative arrays, we suggest several new graphical methods that show some of the patterns of coverage for different designs. As a result, these graphical methods for evaluating covering arrays are illustrated with a few examples.
97 MATHEMATICS AND COMPUTING↗
Emergent classical spacetime from microstates of an incipient black hole
Black holes have an enormous underlying space of microstates, but universal macroscopic physics characterized by mass, charge and angular momentum as well as a causally disconnected interior. This leads two related puzzles: (1) How does the effective factorization of interior and exterior degrees of freedom emerge in gravity?, and (2) How does the underlying degeneracy of states wind up having a geometric realization in the horizon area and in properties of the singularity? We explore these puzzles in the context of an incipient black hole in the AdS/CFT correspondence, the microstates of which are dual to half-BPS states of the $\mathcal{N}$ = 4 super-Yang-Mills theory. First, we construct a code subspace for this black hole and show how to organize it as a tensor product of a universal macroscopic piece (describing the exterior), and a factor corresponding to the microscopic degrees of freedom (describing the interior). We then study the classical phase space and symplectic form for low-energy excitations around the black hole. On the AdS side, we find that the symplectic form has a new physical degree of freedom at the stretched horizon of the black hole, reminiscent of soft hair, which is absent in the microstates. We explicitly show how such a soft mode emerges from the microscopic phase space in the dual CFT via a canonical transformation and how it encodes partial information about the microscopic degrees of freedom of the black hole.
79 ASTRONOMY AND ASTROPHYSICS↗
Phospholipase Cε deficiency delays the early stage of cutaneous wound healing and attenuates scar formation in mice
This study aimed to investigate the role of phospholipase Cε (PLCε) in the skin wound healing process. PLCε, an effect factor of Ras/Rap small G protein, plays a crucial role in skin inflammation by regulating inflammatory cytokines. Inflammatory responses are closely associated with wound healing. Full-thickness skin wounds were made in the PLCε knockout (KO) and wild-type (WT) mice, and the healing process was analyzed. The macroscopic wound closure rate declined in the PLCε KO mice on days 3, 4, and 5 after wounding, following the decreased expression of interleukin (IL)-6, chemokine (C-X-C motif) ligand (Cxcl)-1, Cxcl-2, and chemokine (C-C motif) ligand (Ccl) 20. The proliferation rate of epidermal keratinocytes was not affected by PLCε, but silencing of PLCε resulted in the delayed migration of keratinocytes. Moreover, the scars were found to be much smaller in the PLCε KO mice than in the WT mice. The mRNA expression of Ccl20, collagen (Col) 6a1, and Col17a1 decreased in the PLCε KO mice. These results were in agreement with a previous hypothesis that PLCε might delay the early stage of cutaneous wound healing by inhibiting the migration of keratinocytes, and decrease the expression of Col6a1, Col17a1, and Ccl20 by inhibiting the inflammatory response to reduce scar formation. This study shed light on a novel role of PLCε in wound healing and provided new therapeutic approaches to target PLCε for diminishing scar formation after injury. - Highlights: • Phospholipase Cε deficiency inhibits scar formation. • Phospholipase Cε involves inflammatory cytokine production during wound healing. • Phospholipase Cε deficiency reduces keratinocyte migration. • Phospholipase Cε deficiency decreases collagen production in vivo and in vitro.
60 APPLIED LIFE SCIENCES↗
HMGB1-containing nucleosome mediates chemotherapy-induced metastasis of human lung cancer
Highlights: • Chemotherapy induces invasion and metastasis of human lung cancer. • HMGB1-containing nucleosome drives lung cancer invasion and metastasis. • TLR4 and TLR9 license HMGB1/nucleosome-induced cancer metastasis. • Circulating HMGB1/nucleosome reflects cancer cell invasion in lung cancer patients. While chemotherapy is an important and widely used therapeutic for cancer, it may facilitate cancer metastasis. Herein, we report that human lung cancer cells exert higher invasion and metastasis after chemotherapy. In a human lung cancer xenograft model, chemotherapy promotes the cancer invasion and metastasis in HMGB1-dependent manner. Further studies identify HMGB1-containing nucleosome from chemotherapy-induced apoptotic cancer cells as an effective factor. Such nucleosome functions through TLR4 and TLR9 to drive cancer invasion and metastasis. In lung cancer patients, circulating HMGB1-containing nucleosome is higher in those under chemotherapy, predicting poorly cancer cell differentiation state, enhanced cancer invasion and advanced TNM stages. These findings provide a novel mechanism by which the tumor metastasis is propagated in lung cancer patients, especially in those under chemotherapy, and a clue for developing therapeutic strategies against chemotherapy-induced metastasis.
60 APPLIED LIFE SCIENCES↗