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Breast cancer is a malignant disease with an increasing incidence. Chemotherapy is still an important means for breast cancer treatment, but multidrug resistance (MDR) greatly limits its clinical application. Therefore, the high-efficiency MDR reversal agents are urgently needed. Traditional Chinese medicine (TCM) monomers have unique advantages in reversing chemotherapeutic MDR because of its low toxicity, high efficiency, and ability to impact multiple targets. This review firstly summarizes the major mechanisms of MDR in breast cancer, including the reduced accumulation of intracellular chemotherapeutic drugs, the promoted inactivation of intracellular chemotherapeutic drugs, and the enhanced damage repair ability of DNA, etc., and secondly highlights the research progress of 15 kinds of TCM monomers, including curcumin, resveratrol, emodin, apigenin, tetrandrine, gambogic acid, matrine, paeonol, schisandrin B, [Formula: see text]-elemene, astragaloside IV, berberine, puerarin, tanshinone IIA, and quercetin, in reversing MDR of breast cancer. This review also provides the suggestion for the future research of MDR reversal agents in breast cancer.

Chongqing is one of the focuses of leprosy control in China. Although leprosy control in Chongqing has achieved remarkable results over the years, there are also some problems, such as recurrent epidemics and insufficient early detection in some areas. The aim of this study was to analyze the epidemiological characteristics of leprosy in Chongqing, from 1949 to 2019 and explore the potential factors sociated with cure of leprosy to provide a basis for improving leprosy prevention and treatment strategies in Chongqing. Epidemiological indicators such as incidence and prevalence rates were used to evaluate the prevalence of leprosy. The epidemiological characteristics and control situation of leprosy in patients were analyzed using demographic characteristics, diagnosis, and treatment. Survival analysis was conducted to explore factors associated with the cure of leprosy. From 1949 to 2019, 3,703 cases of leprosy were registered in Chongqing. The incidence of leprosy in the city peaked at 0.853/105 in 1960 and remained below 0.100/105 after 2003. The number of high incidence areas decreased significantly, but they were mainly concentrated in the northeast and southeast regions. The early detection rate increased yearly from 1949 to 2019, and the rate of grade 2 disability ranged from 38.2% to 21.7%, with a fluctuating downward trend after 1960. Male, young age, employment as a farmer, delayed diagnosis, and multibacillary leprosy were risk factors for leprosy cure. Chongqing should continue to strengthen leprosy monitoring to improve the early detection of leprosy and focus on sociated risk factors to carry out multiple strategies.

Epidermolysis bullosa (EB) is a heterogeneous group of rare and incurable genetic blistering disorders.The objective was to analyse the genotype-phenotype correlation in EB among Chinese individuals.Next-generation sequencing and Sanger sequencing were performed to genetically confirm clinically diagnosed EB. Reverse transcription-PCR and splice-site analysis were used to evaluate the consequences of splicing mutations.A total of 441 cases (413 families) across 11 genes were included. EB simplex (EBS), junctional EB (JEB), dystrophic EB (DEB), Kindler EB, simplex and junctional compound EB accounted for 23.4%, 12.7%, 61.5%, 1.1% and 0.2%, respectively. In 16 probands with presumptive recessive EB, failed to find the second allele, COL7A1 (10), COL17A1 (4), LAMB3 (1) and ITGB4 (1). De novo mutations are common in dominant EB (63.8% in EBS, 27.5% in DEB) but extremely rare in recessive DEB (RDEB; 0.74%). Mosaicism is more common than presumed, with 5.4% of dominant EBS. In JEB, only 45.0% of patients with biallelic premature termination codon (PTC) mutations in laminin 332 genes died within 24 months, with a longer average survival age of 11.1 months. In JEB, unusual phenotypes are frequently observed, notably urinary tract involvement, duodenal atresia and EB nevi. In RDEB, 48.8% of cases with biallelic PTC mutations in COL7A1 exhibited a relatively mild phenotype; they are likely to develop a severe phenotype at 0-4 years old, and the PTC mutations position closer to the N-terminal, leading to earlier onset. Glycine substitution mutations in DEB have complex genotypic and phenotypic heterogeneity. The rare subtype, dominant and recessive compound DEB, consists of 1.8% of the total DEB.This study reveals the general rules governing genotype-phenotype correlations, rare phenotypes and complex genotypes. Collectively, mutation analysis in different forms of EB provides the basis for improved subclassification with accurate genetic counselling and for prenatal diagnosis.

Recently, deep federated learning has attracted much attention from researchers in the fields of wireless communications, where the relaying technique has been shown as a powerful technology to assist the wireless signals and enhance the transmission quality, which is very important to the development of mobile edge computing (MEC) based Internet of Things (IoT) networks. In a relaying-aided MEC-IoT system, it is of vital importance to deeply investigate the system signal-to-noise ratio (SNR) at the receiver side, as it mainly determines the system performance metrics, such as capacity (or achievable data rate), outage probability, and bit-error-rate (BER). To this end, we first investigate the instantaneous convergence error, by deeply studying the relationship between the instantaneous two-hop relaying channels. We then investigate the statistical convergence error, by performing the statistical expectation with respect to the two-hop relaying channels. We finally present some results to show that the analysis of the convergence error is effective. The work in this paper can provide some theoretical foundation for deep federated learning and computing networks.

Non-Orthogonal Multiplex Access (NOMA) can be deployed in Unmanned Aerial Vehicle (UAV) networks to improve spectrum efficiency. Due to the broadcasting feature of NOMA-UAV networks, it is essential to focus on the security of the wireless system. This paper focuses on maximizing the secrecy sum-rate under the constraint of the achievable rate of the legitimate channels. To tackle the non-convexity optimization problem, a reinforcement learning-based alternative optimization algorithm is proposed. Firstly, with the help of successive convex approximations, the optimal power allocation scheme with a given UAV trajectory is obtained by using convex optimization tools. Afterwards, through plenty of explorations on the wireless environment, the Q-learning networks approach the optimal location transition strategy of the UAV, even without the wireless channel state information.

Recently, mobile edge computing (MEC) has been widely applied into Internet of Things (IoT) networks, which has attracted a lot of attention from researchers. A critical challenge in the MEC-aided IoT networks is that the performance analysis is often complicated, where it is quite difficult for us to obtain some analytical or closed-form solution to the performance analysis, such as outage probability and bit error rate. This has been the bottleneck of the development of MEC-aided IoT networks. To address this challenge, we deeply investigate the Chebyshev-Gauss approximation method and derive the analytical solution to implement this powerful and useful approximation. We then give several examples to show the effectiveness of the Chebyshev-Gauss approximation in the performance analysis for the MEC-aided IoT systems. The results in this work can serve as an important reference and reveal some important inherent mechanisms for the MEC-aided IoT networks.

In this paper, we analyze the typical product channel which is often encountered in wireless relaying channels, for relaying-assisted edge computing in Internet of Things (IoT) networks. Such analysis is of vital importance, as it is often encountered in wireless transmission. Specifically, we firstly derive a closed-form expression of the transmission outage probability in product channels, through solving involved complicated multivariate integral. We then simplify the expression through some approximation to the involved Bessel function, which can help obtain some meaningful findings to the system design. We finally provide some numerical results to verify that the presented analysis on the production channels is effective.

Human nasal mucosa is susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and serves as a reservoir for viral replication before spreading to other organs (e.g. the lung and brain) and transmission to other individuals. Chronic rhinosinusitis (CRS) is a common respiratory tract disease and there is evidence suggesting that susceptibility to SARS-CoV-2 infection differs between the two known subtypes, eosinophilic CRS and non-ECRS (NECRS). However, the mechanism of SARS-CoV-2 infection in the human nasal mucosa and its association with CRS has not been experimentally validated. In this study, we investigated whether the human nasal mucosa is susceptible to SARS-CoV-2 infection and how different endotypes of CRS impact on viral infection and progression. Primary human nasal mucosa tissue culture revealed highly efficient SARS-CoV-2 viral infection and production, with particularly high susceptibility in the NECRS group. The gene expression differences suggested that human nasal mucosa is highly susceptible to SARS-CoV-2 infection, presumably due to an increase in ACE2-expressing cells and a deficiency in antiviral immune response, especially for NECRS. Importantly, patients with NECRS may be at a particularly high risk of viral infection and transmission, and therefore, close monitoring should be considered.

Pulmonary cryptococcosis is an opportunistic infection of cryptococcus both in immunocompetent and immunocompromised patients, who suffered from HIV infection, organ transplantation, diabetes mellitus, corticosteroid or immunosuppressive therapy, and malignancy. Pulmonary cryptococcosis is the commonest location of non-central nervous system cryptococcosis and usually presents with nonspecific symptoms. It often shows shadows on the lung, which makes it difficult to distinguish it from lung cancer. Here we report a case of a 52-year-old man with pulmonary cryptococcosis, who was misdiagnosed as lung cancer. Clinicians need to consider the possibility of pulmonary cryptococcosis and the importance of lung biopsy when treating a patient with a normal immune function that has isolated pulmonary nodules. This case also indirectly illustrates the importance of percutaneous lung biopsy in patients with isolated pulmonary nodules.

Achieving high network traffic demand in limited spectrum resources is a technical challenge for the beyond 5G and 6G communication systems. To this end, ambient backscatter communication (AmBC) is proposed for Internet-of-Things (IoT), because the backscatter device (BD) can realize communication without occupying extra spectrum resources. Moreover, the spectral efficiency can be further improved by using two-way (TW) communication. However, secure communication is a great challenge for accessing massive IoT devices due to the broadcasting nature of wireless propagation environments. In light of this fact, this article proposed a two-way ambient backscatter communication (TW-AmBC) network with an eavesdropper. Specifically, the physical layer security (PLS) is studied through deriving the analytical/asymptotic expressions of the outage probability (OP) and intercept probability (IP). Moreover, the outage probabilities (OPs) in high signal-to-noise ratio (SNR) regions are studied for the asymptotic behavior and the intercept probabilities (IPs) in high main-to-eavesdropping ratio (MER) regions as well. Through analysis and evaluation of simulation performance, the results show that (i) when considering the target node, the OP of the BD decreases with increasing SNR, that is, enhancing the reliability; (ii) an optimal value of BD’s reflection coefficient that maximize the reliability of backscatter link can be obtained; (iii) in high SNR regions, the OPs approach a constant; thus, the diversity orders are zero; (iv) when increasing the MER, the IP of target node decreases, suggesting the security enhances; (v) a trade-off exists between reliability and security which can be optimized by carefully designing the parameters.

Layered polyaniline intercalated V2O5 with an expanded layer of ∼1.55 nm exhibits an extremely high ammonium storage capacity.

Using a combination of polymer acceptors and small molecule donors (SMD/PA-type) is expected to exhibit easier morphology control because of the different diffusion speeds and solubilities due to their relatively large molecular weight difference, but lack of investigation. In this manuscript, we developed two novel small donor molecules Se-1 and Se-2, with alkyl chains in the π-bridge near the donor core or far away from the donor core. We investigated their effects on the molecular properties, morphologies and device performances of the new type of OSCs. The alkyl chains away from the donor core (Se-2) exhibit ordered molecular packing ability, longer exciton lifetime, and an induced face-on packing mode in the blend. Consequently, the Se-2/polymer acceptor blend, with a concurrently high charge generation and low open-circuit voltage loss, reached a best PCE of 10.3%, which is higher than that of the Se-1/polymer acceptor (9.4%). The result shows the highest PCE in the less investigated SMD/PA-type OSCs. Through comparison of other types of OSCs based on the two small donor materials, we find that the small molecules and PJ1 exhibited high miscibility, and we emphasize the importance of enhancing the Flory–Huggins interaction parameter and molecular crystallinity in further photovoltaic material design in SMD/PA-type OSCs.

Au nanochains with a coupled plasmonic nanostructure were first introduced into PEDOT:PSS used as a hole transport layer to fabricate mixed tin-lead PSCs. The improved electrical properties and the promotion of optical absorption contributed to a high PCE of 19.2%. Moreover, the PSCs show substantial enhancement in stability.

Dataoutputfrom 2-D Hybridsimulations for ''Examining the necessary condition for the second-harmonic generation of EMIC waves: MMS observations and 2-D hybrid simulation''. Data are all '.mat' files which can be loaded into theworkspace of Matlab or Octave directly.Please use the latest version of the data. If you have questionsplease contactxue.zx@whu.edu.cn Descriptions of the contents in the mat file: xmax,zmax: length of the simulation domain in each dimension nx,nz:number of cells in each dimension time: time series bx, by, and bz: magnetic field fluctuations normalized to the background magnetic field, size(bx)=size(by)=size(bz)=[nz, nx, numel(time)]

Diffuse aurora at the Earth’s high latitude regions is mainly caused by the low-energy (0.1–30 keV) electron precipitation which carries the major energy flux into the nightside upper atmosphere. Previous studies have demonstrated that combined scattering by the upper- and lower- band chorus waves acts as the dominant cause of diffuse auroral precipitation, but that is not necessarily the case as these two types of waves do not always occur simultaneously, with the lower-band more often. Here we report that the lower-band chorus satisfying the preferred condition can generate their second harmonics so as to trigger the diffuse auroral electron precipitation. We find that the lower-band chorus alone can only cause the precipitation of electrons greater than 4 keV, while the self-consistently generated second harmonic is weak but still able to result in the electron precipitation below 4 keV. The combined effect of those modes results in the observed pancake electron distributions and the diffuse aurora. Our results clearly demonstrate an alternative but universal mechanism of chorus-driven diffuse aurora in the Earth, which may also apply to the auroral formation in other planetary magnetospheres.

BackgroundThe relationship between retirement and health is important to the formulation of retirement related policies but is a controversial topic, perhaps because selection bias has not been well-addressed in previous studies through traditional analysis methods. Using data from the China Health and Retirement Longitudinal Study (CHARLS), this study explored the potential impact of retirement on the health of elderly Chinese individuals, adjusting for selection bias.MethodsWe balanced the baseline differences between retirement groups and working groups based on nearest neighbor matching and genetic matching with a generalized boosted model (GBM), and regression analysis was used to evaluate the impact of retirement on the health of elderly individuals.ResultsNo significant difference was found in any of the covariates between the two groups after matching. Genetic matching performed better than nearest neighbor matching in balancing the covariates. Compared to the working group, the retirement group had a 0.78 (95% CI: 0.65–0.94, P = 0.026) times higher probability of self-reported physical pain, a 0.76 (95% CI: 0.62–0.93, P = 0.023) times higher probability of depression, and a 0.57-point (95% CI: 0.37–0.78, P < 0.001) improvement in cognitive status score. Among male, the retirement group had a 0.89-point (95% CI: 0.45–1.33, P < 0.001) improvement in cognitive status score for low education, a 0.65 (95% CI: 0.46–0.92, P = 0.042) times higher probability of self-reported physical pain for middle education. For female with low education, the cognitive status of the retirement group was significantly higher by 0.99 points (95% CI: 0.42–1.55, P = 0.004), the probability of depression was 0.56 (95% CI: 0.36–0.87, P = 0.031) times higher in the retirement group than in the working group. There was no difference for the middle and high education.ConclusionRetirement can exert a beneficial effect on the health of elderly individuals. Therefore, the government and relevant departments should consider this potential effect when instituting policies that delay retirement.

Hybrid simulation for EMIC waves

Vehicular social networks (VSNs) are considered as an emerging class of vehicular ad hoc networks (VANETs) with social attributes. In contrast to the traditional randomly distributed human social networks, vehicles normally only move along fixed paths. As such, information sharing and forwarding become challenging because of the high speed of vehicles, complicated propagation environment, and quickly changing network topologies. The social characteristics and human behavior features are used to improve the efficiency of information delivery among vehicles in VANETs. In this paper, we propose a dynamic periodic location encounter network (DPLEN) model that considering both time-varying and location-varying characteristics of vehicles. We calculate the line similarity for each encountered pair of vehicles based on the periodic time and location information of the encounter event, and analyze social attributes based on the network model, such as the Community structure, Betweenness Centrality and K-shell. We also use the similarity to design two routing protocols for unicast and multicast patterns. After testing the proposed model on empirically collected datasets of mobility traces, the results show that these two routing protocols are able to greatly improve the efficiency of information forwarding in the VSNs.

Pancreatic β-cell mass and insulin secretion are determined by the dynamic change of transcription factor expression levels in response to altered metabolic demand. Nuclear factor-Y (NF-Y) is an evolutionarily conserved transcription factor playing critical roles in multiple cellular processes. However, the physiological role of NF-Y in pancreatic β-cells is poorly understood. The current study was undertaken in a conditional knockout of Nf-ya specifically in pancreatic β-cells (Nf-ya βKO) to define the essential physiological role of NF-Y in β-cells. Nf-ya βKO mice exhibited glucose intolerance without changes in insulin sensitivity. Reduced β-cell proliferation resulting in decreased β-cell mass was observed in these mice, which was associated with disturbed actin cytoskeleton. NF-Y–deficient β-cells also exhibited impaired insulin secretion with a reduced Ca2+ influx in response to glucose, which was associated with an inefficient glucose uptake into β-cells due to a decreased expression of GLUT2 and a reduction in ATP production resulting from the disruption of mitochondrial integrity. This study is the first to show that NF-Y is critical for pancreatic islet homeostasis and function through regulation in β-cell proliferation, glucose uptake into β-cells, and mitochondrial energy metabolism. Modulating NF-Y expression in β-cells may therefore offer an attractive approach for therapeutic intervention.

Inspired by both alkaline metal borohydrides and organic-inorganic hybrid perovskite, we predict a pair of complex structures of (CH3NH3)BH4 with tremendous high hydrogen capacity (21.27 wt.%). Through comparison and analysis of the electronic structures of alkali metal atoms, CH3NH3, NH4, and NH3BH3 molecule, it is concluded that similar spatial and electronic structures show the feasibility of synthesizing (CH3NH3)BH4 by a substitution reaction. Firstly, theoretical structures (S1 and S2 in P1) with stable configurations have been reconstructed by cation substitution followed by a series of restrictive structural optimizations, and both the lattice parameters and the position coordinate information of (CH3NH3)BH4 are obtained. Ignoring the relatively mobile hydrogen, the structural symmetries of S1 and S2 are I4mm and P4/nmm, respectively. X-ray diffraction characterizations of S1 and S2 are consistent with the experimental results. Secondly, the calculated elastic constants of (CH3NH3)BH4 (S1 and S2) with P1 symmetry indicate that angles α, β and γ oscillate at right angles due to the influence of the cation orientation. The calculated spatial dependence of bulk (B), Young's (E), and shear (G) modulus obviously show that the two P1 phases all have strong elastic anisotropy. Thirdly, the calculated electronic properties show that the protonic amine-H, hydridic borane-H, and neutral methane-H are widely distributed in (CH3NH3)BH4, which allow for weaving in a planar dihydrogen bonding network, which in turn influences the dehydrogenation reaction. Last and most important, we propose the following dehydrogenation process of (CH3NH3)BH4 via the intermediate compounds: 2(CH3NH3)BH4 → CH3NH2BH2NHCH3BH3+3H2. For each dehydrogenation step, the free energy change is negative, which means (CH3NH3)BH4 can decompose spontaneously, similar to ammonium borohydride, which is strongly related to the planar dihydrogen bonding network.

A phosphine oxide-containing bio-based curing agent was synthesized by addition reaction between furan derivatives and diphenylphosphine oxide. The molecular structure of the as-prepared bio-based curing agent was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. Dynamic mechanical analysis results indicated that with the increase of bio-based curing agent content, the glass transition temperature of epoxy/bio-based curing agent composites decreased, which was related to the steric effect of diphenylphosphine oxide species that possibly hinder the curing reaction as well as the reduction in the cross-linking density by mono-functional N-H. By the addition of 7.5 wt-% bio-based curing agent, the resulting epoxy composite achieved UL-94 V-0 rating, in addition to limiting oxygen index of 32.0 vol-%. With the increase of content for the bio-based curing agent, the peak of heat release rate and total heat release of the composites gradually decreased. The bio-based curing agent promoted the carbonization of the epoxy matrix, leading to higher char yield with good thermal resistance. The high-quality char layer served as an effective barrier to retard the diffusion of decomposition volatiles and oxygen between molten polymers and the flame. This study provides a renewable strategy for fabricating flame retardant and transparent epoxy thermoset.