Abstract
A first hydrostatic core (FHC) is proposed to form after the initial collapse of a prestellar core, as a seed of a Class 0 protostar. FHCs are difficult to observe because they are small, ...compact, embedded, and short lived. In this work, we explored the physical properties of two well-known FHC candidates, B1-bN and B1-bS, by comparing interferometric data from Submillimeter Array (SMA) 1.1 and 1.3 mm and Atacama Large Millimeter/submillimeter Array (ALMA) 870
μ
m observations with simulated synthesis images of the two sources. The simulated images are based on a simple model containing a single, hot compact first-core-like component at the center surrounded by a large-scale, cold and dusty envelope described by a broken power-law density distribution with an index,
α
. Our results show that the hot compact components of B1-bN and B1-bS can be described by temperatures of ∼500 K with a size of ∼4 au, which are in agreement with theoretical predictions of an FHC. If the
α
inside the broken radii is fixed to −1.5, we find
α
∼−2.9 and ∼−3.3 outside the broken radii for B1-bN and B1-bS, respectively, consistent with theoretical calculations of a collapsing, bounded envelope and previous observations. Comparing the density and temperature profiles of the two sources with radiation-hydrodynamic simulations of an FHC, we find both sources lie close to, but before, the second collapse stage. We suggest that B1-bS may have started the collapsing process earlier compared to B1-bN, since a larger discontinuity point is found in its density profile.
Immunologically-cold tumors including glioblastoma (GBM) are refractory to checkpoint blockade therapy, largely due to extensive infiltration of immunosuppressive macrophages (Mϕs). Consistent with a ...pro-tumor role of IL-6 in alternative Mϕs polarization, we here show that targeting IL-6 by genetic ablation or pharmacological inhibition moderately improves T-cell infiltration into GBM and enhances mouse survival; however, IL-6 inhibition does not synergize PD-1 and CTLA-4 checkpoint blockade. Interestingly, anti-IL-6 therapy reduces CD40 expression in GBM-associated Mϕs. We identify a Stat3/HIF-1α-mediated axis, through which IL-6 executes an anti-tumor role to induce CD40 expression in Mϕs. Combination of IL-6 inhibition with CD40 stimulation reverses Mϕ-mediated tumor immunosuppression, sensitizes tumors to checkpoint blockade, and extends animal survival in two syngeneic GBM models, particularly inducing complete regression of GL261 tumors after checkpoint blockade. Thus, antibody cocktail-based immunotherapy that combines checkpoint blockade with dual-targeting of IL-6 and CD40 may offer exciting opportunities for GBM and other solid tumors.
Traumatic brain injury (TBI) is a dominant cause of death and permanent disability worldwide. Although TBI could significantly increase the proliferation of adult neural stem cells in the ...hippocampus, the survival and maturation of newborn cells is markedly low. Increasing evidence suggests that the secretome derived from mesenchymal stem cells (MSCs) would be an ideal alternative to MSC transplantation. The successive and microenvironmentally responsive secretion in MSCs may be critical for the functional benefits provided by transplanted MSCs after TBI. Therefore, it is reasonable to hypothesize that the signaling molecules secreted in response to local tissue damage can further facilitate the therapeutic effect of the MSC secretome. To simulate the complex microenvironment in the injured brain well, we used traumatically injured brain tissue extracts to pretreat umbilical cord mesenchymal stem cells (UCMSCs) in vitro and stereotaxically injected the secretome from traumatic injury‐preconditioned UCMSCs into the dentate gyrus of the hippocampus in a rat severe TBI model. The results revealed that compared with the normal secretome, the traumatic injury‐preconditioned secretome could significantly further promote the differentiation, migration, and maturation of newborn cells in the dentate gyrus and ultimately improve cognitive function after TBI. Cytokine antibody array suggested that the increased benefits of secretome administration were attributable to the newly produced proteins and up‐regulated molecules from the MSC secretome preconditioned by a traumatically injured microenvironment. Our study utilized the traumatic injury‐preconditioned secretome to amplify neurogenesis and improve cognitive recovery, suggesting this method may be a novel and safer candidate for nerve repair.
Cover Image for this issue: doi: 10.1111/jnc.14741
To most closely replicate the complex microenvironment in injured brain, we used extract of traumatic brain tissue to preconditioning umbilical cord mesenchymal stem cells (MSCs) in vitro, and stereotaxically injected these secretome into dentate gyrus of hippocampus in a rat severe Traumatic brain injury (TBI) model. We observed that traumatically preconditioning secretome could significantly further promote the differentiation, migration and maturation of newborn cells in dentate gyrus, and finally improved the cognitive function after TBI. Our study utilized the injury‐preconditioning secretome to inducibly amplify the neurogenesis and cognitive recovery, which can offers a novel and safer candidate for nerve repair.
Open Science: This manuscript was awarded with the Open Materials Badge
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Cover Image for this issue: doi: 10.1111/jnc.14741
Headspace–gas chromatography–ion mobility spectrometry (HS-GC-IMS) coupled with principal component analysis (PCA) was used to investigate the differences in volatile organic compounds (VOCs) in four ...different varieties of Yunnan Huang Tian Ma (containing both winter and spring harvesting times), Yunnan Hong Tian Ma, Yunnan Wu Tian Ma, and Yunnan Lv Tian Ma. The results showed that the flavor substances of different varieties and different harvesting times of Rhizoma gastrodiae were mainly composed of aldehydes, alcohols, ketones, heterocycles, esters, acids, alkenes, hydrocarbons, amines, phenols, ethers, and nitrile. Among them, the contents of the aldehydes, alcohols, ketones, and heterocyclic compounds are significantly higher than those of other substances. The results of cluster analysis and fingerprint similarity analysis based on principal component analysis and Euclidean distance showed that there were some differences between different varieties of Yunnan Rhizoma gastrodiae and different harvesting times. Among them, Yunnan Lv Tian Ma and Wu Tian Ma contained the richest volatile components. Winter may be the best harvesting season for Tian Ma. At the same time, we speculate that the special odor contained in Tian Ma should be related to the aldehydes it is rich in, especially benzene acetaldehyde, Benzaldehyde, Heptanal, Hexanal, Pentanal, and butanal, which are aldehydes that contain a strong and special odor and are formed by the combination of these aldehydes.
Headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) and principal component analysis (PCA) were used to compare the differences in volatile organic compounds (VOCs) of
(Tian Ma) from ...six different origins in Yunnan, Sichuan, Shaanxi, Anhui, Hubei, and Guizhou. A total of 161 signal peaks were identified, and 84 compounds were characterized, including 23 aldehydes, 19 alcohols, 12 ketones, 8 heterocyclic compounds, 7 esters, 4 phenols, 4 acids, 4 ethers, 2 amines, and 1 alkane. The results of cluster analysis and fingerprint similarity analysis based on principal component analysis and Euclidean distance indicated that there were significant differences between the volatile components of
from different origins. This study demonstrated that HS-GC-IMS is simple, rapid, accurate, and has a small sample size and can achieve rapid analysis of the differences in volatile compounds between samples of different origins of
.
Industrial process data are naturally in the form of complex time-series with high nonlinearities and dynamics. Long short-term memory (LSTM) networks are suitable for developing prediction models to ...handle nonlinear and dynamic process. However, LSTM neural networks have typically large and predefined structures, which may result in overfitting, and an optimal hidden neurons for a given problem cannot be automatically obtained. For this reason, a regularized self-organizing LSTM (RSO-LSTM) is proposed to optimize both the structure and the parameters of the network. First, an adaptive learning algorithm based on l2-norm regularization is introduced for parameter adjustment. Thereafter, both the prediction accuracy and weight dispersion are considered to avoid overfitting. Second, a growing strategy is designed based on hidden neuronal sensitivity. The structure of the LSTM can then be determined automatically with improved compactness. Finally, a convergence analysis is performed to ensure the feasibility of RSO-LSTM. To demonstrate the merits of the proposed RSO-LSTM for time-series prediction, its results for three benchmark experiments and real industrial data of a municipal solid waste incineration process were examined and compared with those of other methods. The results indicated the superiority and potential of RSO-LSTM for industrial applications.
•An adaptive learning algorithm based on l2-norm regularization is introduced for parameter adjustment.•The structure of the LSTM can be determined automatically with improved compactness via growth strategy.•The importance of the hidden neurons is measured by neuronal sensitivity.•The convergence of RSO-LSTM can be guaranteed.
We investigate the influence of strong dichromatic laser fields (i.e.,
1
ω
-
2
ω
and
1
ω
-
3
ω
) with high-frequency limit on the cross sections of deuteron-triton (DT) fusion in Kramers-Henneberger ...(KH) frame. We focus on the transitions of phase-dependent effects depending on a dimensionless quantity
n
d
, which equals the ratio of the quiver oscillation amplitude to the geometrical touching radius of the deuteron and triton as defined in our previous research. Theoretical calculations show that the angle-dependent as well as phase-dependent Coulomb barrier penetrabilities can be enhanced in dichromatic intense fields, and the corresponding angle-averaged penetrabilities and the fusion cross sections increase significantly compared with field-free case. Then, we investigate the effects of the two beams with different intensities. Moreover, we find that there are twice shifts of the peak values for the phase-dependent cross sections with the increase of
n
d
. The reason for the first shift is the angle-dependent effects for sub-barrier fusion, while the second shift is due to the accumulation of over-barrier fusion, these mechanisms are analyzed in detail in this paper.
Two new decarestrictine analogs decarestrictine P and penicitone, together with eight known homologous compounds were isolated from the soil fungus from the rhizosphere of Penicillium sp. YUD18003 ...related to Gastrodia elata. Their different structures include a decanolides decartestridine P and a long‐chain polyhydroxyketone penicitone. The structures of new compounds were determined by nuclear magnetic resonance (NMR) spectroscopic analysis and high resolution electrospray ionization mass spectrometry (HR‐ESI‐MS), while their absolute configurations were determined by spectroscopic methods, DP4+ probability analysis, modified Snatzke's method and electron circular dichroism (ECD) calculations. All compounds were evaluated for antimicrobial activities.
According to reports, supplementation with appropriate doses of taurine may help to reduce visual fatigue. Presently, some progress has been made in research related to taurine in eye health, but the ...lack of systematic summaries has led to the neglect of its application in the relief of visual fatigue. This paper, therefore, provides a systematic review of the sources of taurine, including the endogenous metabolic and exogenous dietary pathways, as well as a detailed review of the distribution and production of exogenous taurine. The physiological mechanisms underlying the production of visual fatigue are summarized and the research progress of taurine in relieving visual fatigue is reviewed, including the safety of consumption and the mechanism of action in relieving visual fatigue, in order to provide some reference basis and inspiration for the development and application of taurine in functional foods for relieving visual fatigue.
•Different model parameters affect the prediction accuracy of SVM model differently.•Training sample size can also influence the prediction accuracy of SVM model.•The method of determining the ...optimal SVM regression model is summarized.•Prediction accuracy of SVM model improves greatly by applying the method promoted.•The MAPE of the optimal model decrease from 12.54% to 8.32%.•The MRE of the optimal model decrease from 56.66% to 25.89%.
In recent years, support vector machine (SVM) method has been rapidly developed because of its great advantage in solving small sample regression problems. Based on the prediction accuracy of NOx emission, the SVM method is applied to the regression analysis of the steady-state calibration experimental results of a hydrogen enriched compressed natural gas (HCNG) engine in this research article. The effects of the model parameters (penalty factor kernel, function width and insensitive band loss function) and the training sample size on the prediction accuracy of the regression model are studied. Results show that both model parameters and training sample size can influence the prediction accuracy of the SVM model. Additionally, the method of determining the optimal SVM regression model is also summarized. The optimal SVM regression model is obtained by the manifold absolute pressure (MAP) and the fuel equivalence ratio (θ) halved sample, with the training sample size of 270 for the experimental data used in this study. Results show that the optimal SVM regression model can decrease the predicted mean absolute percentage error (MAPE) and the maximum relative prediction error (MRE) of the brake specific NOx emission greatly, from 12.54% to 8.32% and 56.66% to 25.89%, respectively. It indicates that the prediction performance can be improved apparently by the method promoted in the paper, which provides a new perspective for the further application of SVM method in the field of automobile engines calibration.
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