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Cell fate decision is crucial in biological development and plays fundamental roles in normal development and functional maintenance of organisms. By identifying key regulatory interactions and molecules involved in these fate decisions, we can shed light on the intricate mechanisms underlying the cell fates. This understanding ultimately reveals the fundamental principles driving biological development and the origins of various diseases. In this study, we present an overarching framework which integrates pseudo-trajectory inference and differential analysis to determine critical regulatory interactions and molecules during cell fate transitions. To demonstrate feasibility and reliability of the approach, we employ the differentiation networks of hepatobiliary system and embryonic stem cells as representative model systems. By applying pseudo-trajectory inference to biological data, we aim to identify critical regulatory interactions and molecules during the cell fate transition processes. Consistent with experimental observations, the approach can allow us to infer dynamical cell fate decision processes and gain insights into the underlying mechanisms which govern cell state decisions. [ABSTRACT FROM AUTHOR]

Motivated by the effect of symmetry breaking in cuprates superconductors YBa 2 Cu 3 O 7 - δ , we employ the renormalized mean-field theory to study the presence of uniform superconducting and charge-ordered states in two anisotropic t–J–U models, either with hopping strength anisotropy or antiferromagnetic interaction anisotropy. In the case of uniform superconducting state, compared with the isotropic t–J–U model with only d x 2 - y 2 -wave superconducting state, there is an additional s-wave superconducting state in the model with hopping strength anisotropy. Meanwhile, the hopping anisotropy may enhance the critical Coulomb interaction U c at the Mott insulator to the Gossamer superconductor transition point, and strong hopping anisotropy may weaken the superconducting state. In the case of a charge-ordered state, hopping anisotropy may suppress the amplitude of the charge density waves and pair density waves, which originate from local Coulomb interactions. These results indicate that the effects of hopping anisotropy and local Coulomb interactions are competitive. Moreover, the antiferromagnetic interaction anisotropy only weakly suppresses the superconducting gap and density wave amplitude. Our results show that the t–J–U model with hopping anisotropy is qualitatively consistent with experimental superconducting pair symmetry and charge density waves in the YBa 2 Cu 3 O 7 - δ system. [ABSTRACT FROM AUTHOR]

Cell fate decisions and transitions are common in almost all developmental processes. Therefore, it is important to identify the decision-making mechanisms and important individual molecules behind the fate decision processes. In this paper, we propose an interpretable strategy based on systematic perturbation, unsupervised hierarchical cluster analysis (HCA), machine learning (ML), and Shapley additive explanation (SHAP) analysis for inferring the contribution and importance of individual molecules in cell fate decision and transition processes. In order to verify feasibility of the approach, we apply it to the core epithelial to mesenchymal transition (EMT)-metastasis network. The key factors identified in EMT-metastasis are consistent with relevant experimental observations. The approach presented here can be applied to other biological networks to identify important factors related to cell fate decisions and transitions. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new stochastic discrete-time multi-scale model to quantify the co-evolution of behavior changes and COVID-19. In this model, initial values and parameters of behavior change are used to describe individual behavior before and during the epidemic, and diagnosis rate parameters are used to describe government policies. In order to comprehensively reflect the characteristics of the epidemic in China, the epidemic data of three representative cities were selected for analysis and research based on the principles of traffic status, epidemic outbreak degree and epidemic data distribution. Firstly, the sensitivity analysis of parameters obtained from data fitting of three cities was carried out, respectively. It was found that different cities have different parameter sensitivities, but the sensitivity of initial value of behavior change was the strongest in all the three cities. Secondly, control measures such as phased unlocking were added to observe the impact of these control measures on secondary outbreaks based on behavior changes. Finally, considering that the Chinese government has fully relaxed the control of the epidemic, we further simulated the epidemic curve with only behavior changes and no government policies, and found that under the same behavior change, the epidemic curve in places with more severe outbreaks will change more, revealing the role of behavior change in secondary and multiple outbreaks. [ABSTRACT FROM AUTHOR]

To investigate the correlation between electrochemical performance and physicochemical properties, three types of 1D WO3 nanostructures were fabricated by hydrothermal method using K2SO4, Na2SO4, and (NH4)2SO4 as capping agents. Hexagonal phase was obtained with the assistant of Na2SO4 and (NH4)2SO4, while monoclinic phase was developed using K2SO4 as agent. WO3 nanostructures prepared by (NH4)2SO4 and Na2SO4 exhibited superior specific capacitance (400 F/g and 388 F/g) relative to WO3 prepared by K2SO4 (259 F/g), suggesting hexagonal phase is more suitable for energy storage. The nanostructures prepared using Na2SO4 exhibited inferior rate performance compared with those obtained by (NH4)2SO4 due to low specific surface area and high crystallinity. The electrochemical performance demonstrated nanostructures prepared by (NH4)2SO4 was surface-controlled whereas those using Na2SO4 and K2SO4 were battery-type material. These findings raise the prospects of developing tungsten oxide for energy storage. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) were treated by reflux oxidation in a mixture (HNO3 and H2SO4), hydroxyl (–OH) and carboxyl (–COOH) functional groups were introduced on the surface of MWCNTs to obtain the Oxidized-MWCNTs (OMWCNTs). OMWCNTs were used as adsorbent to removal of Pb(II) from wastewater. The effects of contact time, initial concentration of Pb(II), OMWCNTs dosage, pH and coexisting ions (K+, Na+, Ca2+, Mg2+) on the adsorption and removal of Pb(II) by OMWCNTs were systematically studied. The adsorption of Pb(II) by OMWCNTs could reach equilibrium in 10 min. The pH > 5 is conductive to the adsorption of Pb(II) by OMWCNTs. The coexisting ions (K+, Na+, Ca2+, Mg2+) had almost no effect on the adsorption of Pb(II) by OMWCNTs. The results showed that the isothermal data fit the Freundlich and Langmuir isotherm models. The maximum adsorption capacity was 558.66 mg/g for Pb(II) from Langmuir isotherm. The pseudo-second-order kinetic model could well describe the adsorption process of Pb(II). [ABSTRACT FROM AUTHOR]

Wastewater remediation using microbial fuel cells (MFC) is an advanced method to produce energy and reduce environmental pollution, yet actual energy yields are low and mineral matter is hardly removed. Here we constructed a dual-membrane cylinder photo-microbial fuel cell (DCP-MFC), equipped with cation and anion exchange membranes, to produce electricity and microalgae, and to remove both organics and minerals. Results show that this cell displayed higher electric generation capacity, of 671.6 mV and 0.39 W/m2, during 1000 h of stable running, than the control cell, of 601.2 mV and 0.31 W/m2. Microalgal biomass increased from 2.90 to 3.80 g/L owing to dissolved oxygen scavenging. Nitrogen recovery increased from 0 to 92.6%. Energy yield increased from 2.33 kJ for the control MFC to 118.28 kJ for microalgal cultivation, and to 155.21 kJ for the DCP-MFC. Microbial community analysis revealed that nitrate was mostly converted into nitrite by denitrifying bacteria in the anode chamber, then used by microalgae in the cathode chamber of the DCP-MFC. [ABSTRACT FROM AUTHOR]

This study was conducted to prepare β-caryophyllene loaded liposomes (BCP-LP) and investigated their effects on neurovascular unit (NVU) damage after subarachnoid hemorrhage (SAH) in rats. A blood injection into the pre-chiasmatic cistern was used to achieve SAH. BCP-LP were prepared, characterized and administrated to rats with SAH. The prepared BCP-LP were spherical with a size distribution of approximately 189.3 nm and Zeta potential of − 13.9 mV. Neurological scoring, the balance beam test, cerebral blood flow monitoring, brain edema and biochemical analyses were applied to evaluate the effects of BCP-LP on rat NVU damage after SAH. The results demonstrated that BCP-LP treatment improved neurological function disorder, balance ability and cerebral blood perfusion in rats. Brain edema detection and blood–brain barrier permeability detection revealed that BCP-LP could reduce brain edema and promote repairment of blood–brain barrier after SAH. Using the western blot experiments, we demonstrated that BCP-LP attenuated the loss of tight junction proteins Occludin and Zonula occludens-1, inhibit the high expression of VEGFR-2 and GFAP, and promote the repair of laminin. These results demonstrate the protective effect BCP-LP exert in the NVU after SAH in rats, and supports the use of BCP-LP for future study and therapy of SAH. [ABSTRACT FROM AUTHOR]

We study the two-dimensional Bose-Fermi mixture on square lattice at finite temperature by using the determinant quantum Monte Carlo method within the weakly interacting regime. Here we consider the attractive Bose-Hubbard model and free spinless fermions. In the absence of boson-fermion interactions, we obtain the boundary of the collapsed state of the attractive bosons. In the presence of boson-fermion interactions, an effective p-wave interaction between fermions will be induced as far as the bosons are in a superfluid state. Moreover, we find the emergence of the composite fermion pairs at low temperatures. [ABSTRACT FROM AUTHOR]

Low-permittivity Sr2MgSi2O7 ceramics with tetragonal crystal structure were prepared through the conventional solid-state method. X-ray diffraction patterns and scanning electron microscopy were used to analyze the phase and micromorphology of the specimens sintered at temperature from 1260 to 1320 °C. The bond ionicity, lattice energy and bond energy of Sr2MgSi2O7 ceramics were calculated to investigate the relationships between microwave dielectric properties and microstructures. Optimum microwave dielectric properties were obtained when the sample was sintered at 1280 °C for 4h: εr = 6.85, Q × f0 = 22,530 GHz (f = 9.20 GHz), τf = − 32 ppm/°C. [ABSTRACT FROM AUTHOR]

Monoclinic structured MgNiZrNbO (0 ≤ x ≤ 0.12) ceramics were synthesized for the first time through traditional solid-state reaction process and pure phase were obtained in all range. Rietveld refinement was used to analyze the crystal structure. With the increase of Ni substitution amount, ε decreased, Q × f rose first then fell, τ shifted for the positive direction. Bond ionicity, lattice energy and bond energy were separately calculated to investigate the correlations with microwave dielectric properties. Typically, ceramics samples with the composition of MgNiZrNbO sintered at 1280 °C for 4 h exhibited the optimum microwave dielectric properties: ε = 24.58, Q × f = 74534.1 GHz, τ = − 49.11 ppm/°C, which could be a promising material for application. [ABSTRACT FROM AUTHOR]

β-Caryophyllene (BCP) has been reported to be protective against focal cerebral ischemia-reperfusion (I/R) injury by its anti-oxidative and anti-inflammatory features. Recent study demonstrates that the BCP exhibits potential neuroprotection against I/R injury induced apoptosis, however, the mechanism remains unknown. Therefore, we investigate the underlying anti-apoptotic mechanism of BCP pretreatment in I/R injury. Sprague-Dawley rats (pretreated with BCP suspensions or solvent orally for 7 days) were subjected to transient Middle Cerebral Artery Occlusion (MCAO) for 90 min, followed by 24 h reperfusion. Results showed that BCP pretreatment improved the neurologic deficit score, lowered the infarct volume and decreased number of apoptotic cells in the hippocampus. Moreover, in western blot and RT-qPCR detections, BCP pretreatment down-regulated the expressions of Bax and p53, up-regulated the expression of Bcl-2, and enhanced the phosphorylation of Akt on Ser473. Blockage of PI3K activity by wortmannin not only abolished the BCP-induced decreases in infarct volume and neurologic deficit score, but also dramatically abrogated the enhancement of AKt phosphorylation. Our results suggested that BCP pre-treatment protects against I/R injury partly by suppressing apoptosis via PI3K/AKt signaling pathway activation. [ABSTRACT FROM AUTHOR]

Versicolols A and B ( 1 and 2), two rare prenylated isocoumarin derivatives, along with five known isocoumarins ( 3- 7) were isolated from the fermentation products of an endophytic fungus Aspergillus versicolor. Their structures were elucidated on the basis of extensive spectroscopic analysis, including 1D- and 2D-NMR techniques. Compounds 1 and 2 were evaluated for their cytotoxicity against five human tumor cell lines. The results showed that compounds 1 exhibited weak cytotoxicity against A549 and MCF7 cells with IC values of 9.4 and 8.8 μm, and compound 2 exhibited weak cytotoxicity against SHSY5Y and MCF7 cells with IC values of 8.2 and 6.8 μm, respectively. [ABSTRACT FROM AUTHOR]

This study aimed to identify the effect of β-caryophyllene (BCP) pretreatment and elucidate the Nrf2/HO-1 signaling mechanism after focal cerebral ischemia-reperfusion (I-R) injury in rats. Adult male Sprague-Dawley rats were randomly assigned to the sham-operated group, I-R group and BCP pretreated I-R group. At 24 h after reperfusion, neurological deficits and infarct volume were evaluated. Pathological changes of neuron in hippocampuses were observed by Nissil staining and transmission electron microscopy (TEM). Oxidative stress was assessed by malondialdehyde (MDA) level, lipid peroxidation (LPO), nitric oxide (NO), superoxide dismutase (SOD) and Catalase (CAT) activity. The expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) were analysed by Western blotting and real-time quantitative polymerase chain reaction (Q-PCR). The protein expression of Bcl-2 and Bax was determined by immunohistochemistry. Apoptotic cells were detected using TUNEL staining. In I-R group, neurological deficit scores, cerebral infarct volume, MDA levels, LPO content, NO level, expression of Bax and TUNEL-positive cells were found to be increased at 24 h after I-R injury, while SOD activity, CAT activity and expression of Bcl-2 were decreased. However, results in the BCP pretreatment groups were reversed. And the protein and mRNA expressions of Nrf2 and HO-1 were significantly up-regulated in the BCP pretreated I-R group. Results of Nissil staining and TEM scan manifested that BCP remarkablely improved neuronal injury after I-R in rats. All the above suggested that BCP pretreatment played a neuroprotective role in cerebral I-R injury, which might be exerted by upregulating the expression of Nrf2 and HO-1 to ameliorate oxidative damage and neuronal apoptosis. [ABSTRACT FROM AUTHOR]

Social media systems with Q&A functionalities have accumulated large archives of questions and answers. Two representative types are online forums and community-based Q&A services. To enable users to explore the large number of questions and answers in social media systems effectively, it is essential to suggest interesting items to an active user. In this article, we address the problem of question suggestion, which targets at suggesting questions that are semantically related to a queried question. Existing bag-of-words approaches suffer from the shortcoming that they could not bridge the lexical chasm between semantically related questions. Therefore, we present a new framework, and propose the topic-enhanced translation-based language model (TopicTRLM), which fuses both the lexical and latent semantic knowledge. This fusing enables TopicTRLM to find semantically related questions to a given question even when there is little word overlap. Moreover, to incorporate the answer information into the model to make the model more complete, we also propose the topic-enhanced translation-based language model with answer ensemble. Extensive experiments have been conducted with real-world datasets. Experimental results indicate our approach is very effective and outperforms other popular methods in several metrics. [ABSTRACT FROM AUTHOR]

The current study focuses on the removal of perchlorate in water using single-walled carbon nanotubes (SWCNTs) and granular ferric hydroxide as sorbents. The randomly distributed tubes were observed by scanning electron microscopy. The influence of temperature and content of natural humic acid on the perchlorate adsorption capacity was examined at pH 3. The adsorption data were fitted with three models: modified Freundlich, pseudo-first order, and pseudo-second order. The modified Freundlich model produced the best fit to describe the kinetic adsorption processes. The adsorption capacities of perchlorate measured at 25 °C and pH 3 using single-walled carbon nanotubes and granular ferric hydroxide were about 6 and 3 mg/g, respectively. The influence of natural humic acid on perchlorate adsorption by SWCNTs was examined. Natural humic acid was derived from raw water in Gao-Ping River in south Taiwan. Lower adsorption reaction rates of perchlorate were obtained at higher humic acid concentrations. High humic acid concentrations induce the compression of the electric double layer that consequently reduces the surface potential energy and electrostatic repulsion. [ABSTRACT FROM AUTHOR]

This study investigated the use of biological activated carbon filters (BACF) to reduce the amounts of disinfection by-products (DBPs) in treated drinking water in a water treatment plant. To accomplish this, experiments were conducted in a pilot-scale treatment system to evaluate the removal of trihalomethanes (THMs) and haloacetic acids (HAAs) by BACF. The results showed that BACF treatment reduced the total concentration of THMs and HAAs to meet the national drinking water standard in Taiwan. The predicted and measured values of THMs and HAAs in output water treated with a BACF showed linear relationships, with correlation coefficients ( R) of 0.83 and 0.84, respectively. The results of two predictive equations of DBPs using parameters of water quality, such as total organic carbon, dissolved organic carbon, ammonia nitrogen, ultraviolet, and total phosphorous were also established. The results of the present study can be used as a reference for water treatment plants or water distribution systems that provide drinking water. [ABSTRACT FROM AUTHOR]

The purposes of this paper are twofold: to develop a rigorous approach to analyze the threshold behaviors of nonlinear virus dynamics models with impulsive drug effects and to examine the feasibility of virus clearance following the Manuals of National AIDS Free Antiviral Treatment in China. An impulsive system of differential equations is developed to describe the within-host virus dynamics of both wild-type and drug-resistant strains when a combination of antiretroviral drugs is used to induce instantaneous drug effects at a sequence of dosing times equally spaced while drug concentrations decay exponentially after the dosing time. Threshold parameters are derived using the basic reproduction number of periodic epidemic models, and are used to depict virus clearance/persistence scenarios using the theory of asymptotic periodic systems and the persistence theory of discrete dynamical systems. Numerical simulations using model systems parametrized in terms of the antiretroviral therapy recommended in the aforementioned Manuals illustrate the theoretical threshold virus dynamics, and examine conditions under which the impulsive antiretroviral therapy leads to treatment success. In particular, our results show that only the drug-resistant strain can dominate (the first-line treatment program guided by the Manuals) or both strains may be rapidly eliminated (the second-line treatment program), thus the work indicates the importance of implementing the second-line treatment program as soon as possible. [ABSTRACT FROM AUTHOR]

Stability of drinking water can be indicated by the assimilable organic carbon (AOC). This AOC value represents the regrowth capacity of microorganisms and has large impacts on the quality of drinking water in a distribution system. With respect to the effectiveness of traditional and advanced processing methods in removing trace organic compounds (including TOC, DOC, UV, and AOC) from water, experimental results indicate that the removal rate of AOC at the Cheng Ching Lake water treatment plant (which utilizes advanced water treatment processes, and is hereinafter referred to as CCLWTP) is 54%, while the removal rate of AOC at the Gong Yuan water treatment plant (which uses traditional water treatment processes, and is hereinafter referred to as GYWTP) is 36%. In advanced water treatment units, new coagulation-sedimentation processes, rapid filters, and biological activated carbon filters can effectively remove AOC, total organic carbon (TOC), and dissolved organic carbon (DOC). In traditional water treatment units, coagulation-sedimentation processes are most effective in removing AOC. Simulation results and calculations made using the AutoNet method indicate that TOC, TDS, NH-N, and NO-N should be regularly monitored in the CCLWTP, and that TOC, temperature, and NH-N should be regularly monitored in the GYWTP. [ABSTRACT FROM AUTHOR]

mathematical model describing the antiretroviral therapy of Enfuvirtide on HIV-1 patients is developed. The effect of Enfuvirtide (formerly called T-20) by impulsive differential equations is modeled by two different drug elimination kinetics, the first-order elimination kinetics and the Michaelis-Menten elimination kinetics. The model is a non-autonomous system of differential equations. For a time-dependent system, the disease-free equilibrium is mainly studied. Its stability, when the therapy is taken with perfect adherence, is obtained. To ensure the disease-free equilibrium remains stable, the analytical thresholds for dosage and dosing intervals are determined. The effects of supervised treatment interruption are also explored. It is shown that the supervised treatment interruption can be worse than no therapy at all. [ABSTRACT FROM AUTHOR]

A four dimension ODE model is built to study the infection of human immunodeficiency virus (HIV) in vivo. We include in this model four components: the healthy T cells, the latent-infected T cells, the active-infected T cells and the HIV virus. Two types of HIV transmissions in vivo are also included in the model: the virus-to-cell transmission, and the cell-to-cell HIV transmission. There are two possible equilibriums: the healthy equilibrium, and the infected steady state. The basic reproduction number R 0 is introduced. When R 0 < 1, the healthy equilibrium is globally stable and when R 0 > 1, the infected equilibrium exists and is globally stable. Through simulations, we find that, the cell-to-cell HIV transmission is very important for the final outcome of the HIV attacking. Some important clinical observations about the HIV infection situation in lymph node are also verified. [ABSTRACT FROM AUTHOR]

The probability is introduced to formulate the death of individuals, the recovery of the infected individuals and incidence of epidemic disease. Based on the assumption that the number of individuals in a population is a constant, discrete-time SI and SIS epidemic models with vital dynamics are established respectively corresponding to the case that the infectives can recover from the disease or not. For these two models, the results obtained in this paper show that there is the same dynamical behavior as their corresponding continuous ones, and the threshold determining its dynamical behavior is found. Below the threshold the epidemic disease dies out eventually, above the threshold the epidemic disease becomes an endemic eventually, and the number of the infectives approaches a positive constant. [ABSTRACT FROM AUTHOR]

In this paper, we consider a more realistic model than a previous one (Lou et al. in Math Biosci Eng 3:313, 2006) for an HIV-1 dynamical model incorporating the AIDS-related cancer cells in tissue cultures. In order to improve the description of the phenomenon, we have taken into account also the time delay for the incubation phase when the target cells are infected. The model involves three cell populations: cancer cells, healthy and infected CD4+ T lymphocytes and we verify that there exists up to six steady states. We discuss the existence, the stability properties and the biological meanings of the steady states, focusing in particular on the positive one: cancer- HIV-healthy cells steady state. We find Hopf bifurcation of the positive steady state, leading to periodic solutions and chaos. By means of numerical simulations the effect of the delay is analyzed and we find that the existence of infected quiescent memory T cells is one of the important reasons for which the HIV-1 infected individual develops AIDS. [ABSTRACT FROM AUTHOR]

In this paper, we develop a computational linguistic approach based on supervised machine learning using the People's Daily to measure Chinese official relations and political uncertainty towards the US. In the first step, we create training samples by asking experts to manually annotate news articles. In the second step, we use supervised machine learning algorithms to adjust our single neural network and support vector machine classifiers to better fit our training data. Finally, we combine our two individual classifiers and a dictionary approach to automatically detect whether an article in the newspaper sample is relevant. Using all of the relevant textual data, we then apply the computational linguistic approach to generate state-of-the-art indices and show that our indices outperform similar current textual indicators in some situations, particularly in the financial market., Supplementary Information: The online version contains supplementary material available at 10.1007/s43546-022-00209-2., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2022.)