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Background The 340B Drug Pricing Program has been controversial since its inception in 1992, a major criticism being that 340B hospitals use more outpatient drugs, and more expensive drugs, because of financial incentives to “make money” through the program. The goal of this study was to determine whether characteristics of patients treated at 340B hospitals, and affiliation of hospitals with NCI-designated cancer centers, would explain higher Part B drug costs and use of more expensive chemotherapy drugs. Methods This is an observational study using data from SEER-Medicare and 340B entity database. Fee-for-service Medicare beneficiaries who were first diagnosed with cancer between 1/1/2013 and 12/31/2015 were included. Hospital, patient, and cancer/clinical characteristics were used as predictors of both overall Part B drug costs and use of expensive chemotherapy drugs. Patient characteristics and cancer conditions were compared between those who were treated at 340B and non-340B hospitals, and between those who used and who did not use any expensive chemotherapy treatment. Independent relationships between overall Part B drug costs and patients’ 340B status, and between patients’ use of expensive chemotherapy drug and patients’ 340B status were evaluated in multivariate analyses, using a “stepwise” generalized estimating equation modeling approach. Results We found that patients at 340B hospitals had a somewhat higher chance of using one of the ten expensive chemotherapy drugs, and somewhat higher overall drug costs, but these relationships became non-significant when patient, cancer/clinical factors, and cancer center status were considered. Compared to the reference patients, patients who were treated in an NCI-designated cancer center or a hospital affiliated with such center, who had certain types of cancers (e.g., B-cell), or had advanced-stage disease had a higher chance to use expensive chemotherapy treatment; patients who were older, survived the first 12 months upon diagnosis, had advanced-stage disease, or had more drug claims had higher drug costs. Conclusions Hospital 340B status was not significantly associated with use of more expensive cancer drugs or drug costs once other relevant factors (e.g., cancer center status, advanced-stage disease) were taken into account.

Background As a type of calmodulin binding protein, CAMTAs are widely involved in vegetative and reproductive processes as well as various hormonal and stress responses in plants. To study the functions of CAMTA genes in tea plants, we investigated bioinformatics analysis and performed qRT-PCR analysis of the CAMTA gene family by using the genomes of ‘ShuChaZao’ tea plant cultivar. Results In this study, 6 CsCAMTAs were identified from tea plant genome. Bioinformatics analysis results showed that all CsCAMTAs contained six highly conserved functional domains. Tissue-specific analysis results found that CsCAMTAs played great roles in mediating tea plant aging and flowering periods. Under hormone and abiotic stress conditions, most CsCAMTAs were upregulated at different time points under different treatment conditions. In addition, the expression levels of CsCAMTA1 / 3 / 4 / 6 were higher in cold-resistant cultivar ‘LongJing43’ than in the cold-susceptible cultivar ‘DaMianBai’ at cold acclimation stage, while CsCAMTA2 / 5 showed higher expression levels in ‘DaMianBai’ than in ‘LongJing43’ during entire cold acclimation periods. Conclusions In brief, the present results revealed that CsCAMTAs played great roles in tea plant growth, development and stress responses, which laid the foundation for deeply exploring their molecular regulation mechanisms.

Background The tea plant ( Camellia sinensis (L.) O. Kuntze) is one of the most economically important woody crops. Plastic greenhouse covering cultivation has been widely used in tea areas of northern China. Chlorophyll is not only the crucial pigment for green tea, but also plays an important role in the growth and development of tea plants. Currently, little is known about the effect of plastic greenhouse covering cultivation on chlorophyll in tea leaves. Results To investigate the effect of plastic greenhouse covering cultivation on chlorophyll in tea leaves, color difference values, chlorophyll contents, gene expression, enzyme activities and photosynthetic parameters were analyzed in our study. Sensory evaluation showed the color of appearance, liquor and infused leaves of greenhouse tea was greener than field tea. Color difference analysis for tea liquor revealed that the value of ∆L, ∆b and b/a of greenhouse tea was significantly higher than field tea. Significant increase in chlorophyll content, intracellular CO 2 , stomatal conductance, transpiration rate, and net photosynthetic rate was observed in greenhouse tea leaves. The gene expression and activities of chlorophyll-metabolism-related enzymes in tea leaves were also activated by greenhouse covering. Conclusion The higher contents of chlorophyll a, chlorophyll b and total chlorophyll in greenhouse tea samples were primarily due to higher gene expression and activities of chlorophyll-metabolism-related enzymes especially, chlorophyll a synthetase (chlG), pheophorbide a oxygenase (PAO) and chlorophyllide a oxygenase (CAO) in tea leaves covered by greenhouse. In general, our results revealed the molecular basis of chlorophyll metabolism in tea leaves caused by plastic greenhouse covering cultivation, which had great significance in production of greenhouse tea.

The new crossed cable-truss spoke structure (CCTSS) significantly improves the lateral stiffness and integral stability of the ordinary spoke cable-truss structure, but it still has the shortcomings of general tensile structures, like low redundancy and weak collapse resistance. Its collapse resistance is still unclear. In the paper, the structural characteristics of CCTSS are introduced. Secondly, the influence of initial prestresses on the collapse performance of CCTSS is studied. Then the collapse response features and collapse mechanism of the members and joints of CCTSS are revealed under the actions of no loads, full-span loads and half-span loads. Finally, a calculation method of the dynamic force amplification coefficient is proposed based on the collapse results of CCTSS, and a calculation method of the importance of members and joints is further proposed based on the dynamic internal force amplification coefficient, which indirectly evaluates structural collapse resistance. The results show that CCTSS has good local collapse resistance, but the failure of ring cables and joints at the ring cables will cause the structure to lose its integral bearing capacity. Meanwhile, the proposed calculation method of the importance of components and joints has a simple calculation process and is convenient to utilize, which has good engineering application value. The research content provides a theoretical basis and analysis method for structural safety design.

Background Autophagy, meaning ‘self-eating’, is required for the degradation and recycling of cytoplasmic constituents under stressful and non-stressful conditions, which helps to maintain cellular homeostasis and delay aging and longevity in eukaryotes. To date, the functions of autophagy have been heavily studied in yeast, mammals and model plants, but few studies have focused on economically important crops, especially tea plants ( Camellia sinensis ). The roles played by autophagy in coping with various environmental stimuli have not been fully elucidated to date. Therefore, investigating the functions of autophagy-related genes in tea plants may help to elucidate the mechanism governing autophagy in response to stresses in woody plants. Results In this study, we identified 35 C. sinensis autophagy-related genes ( CsARG s). Each CsARG is highly conserved with its homologues from other plant species, except for CsATG14 . Tissue-specific expression analysis demonstrated that the abundances of CsARG s varied across different tissues, but CsATG8c / i showed a degree of tissue specificity. Under hormone and abiotic stress conditions, most CsARG s were upregulated at different time points during the treatment. In addition, the expression levels of 10 CsARG s were higher in the cold-resistant cultivar ‘Longjing43’ than in the cold-susceptible cultivar ‘Damianbai’ during the CA period; however, the expression of CsATG101 showed the opposite tendency. Conclusions We performed a comprehensive bioinformatic and physiological analysis of CsAR Gs in tea plants, and these results may help to establish a foundation for further research investigating the molecular mechanisms governing autophagy in tea plant growth, development and response to stress. Meanwhile, some CsARGs could serve as putative molecular markers for the breeding of cold-resistant tea plants in future research.

Shandong matcha has the quality characteristics of bright green color, seaweed-like aroma and strong, fresh and brisk taste. In order to identify the characteristic aroma components and clarify the contribution of the grinding process to the aroma of Shandong matcha. Three grades of Shandong matcha and corresponding tencha material were firstly tested with sensory evaluation, and the volatile components were extracted with headspace solid-phase microextraction (HS-SPME) and solvent-assisted flavor evaporation (SAFE) and analyzed using GC–MS. The sensory evaluation results showed that high-grade matcha (M-GS) had prominent seaweed-like, fresh and roasted notes, whereas medium and low-grade matcha (M-G1, M-G2) were gradually coupled with grassy, fatty and high-fired aromas. GC–MS results showed that in the HS-SPME method, heterocyclic compounds (45.84–65.35%) were the highest in Shandong matcha, followed by terpenoids (7.44–16.92%) and esters (6.91–15.27%), while in the safe method, esters were the highest (12.96–24.99%), followed by terpenoids (10.76–25.09%) and heterocyclic compounds (12.12–17.07%). As a whole, the composition of volatile components between M-G1 and M-G2 is relatively close, and there are more differences in volatile components between them and M-GS. The volatile components unique to M-GS were screened using the odor activity value (OAV) evaluation method, with components such as 3-methyl-2-butene-1-thiol, 3-ethyl-Phenol, 2-thiophenemethanethiol, 2,4-undecadienal, (E,E)-2,6-nonadienal, (E,Z)- being evaluated. There were other differentially volatile components, that is, volatile components that coexist in the three grades of matcha, but with different concentrations and proportions. M-G1 and M-G2 contained more volatile substances with high-fired aroma, such as 2-ethyl-3-methyl-pyrazine, coumarin and 5,6,7,8-tetrahydroquinoxaline. The grinding process not only changes the appearance of tencha, but also increases the content of volatile components of matcha as a whole, enhancing the aroma and flavor characteristics of matcha. In this study, the contents of 24 volatile components in matcha were mainly increased, such as benzene, (2,2-dimethoxyethyl)-, cis-7-decen-1-al, safranal and fenchyl acetate. The dual factors of material tencha and matcha grinding technology are indispensable in forming the differences in aroma and flavor of Shandong matcha at different levels.

The type of adventitious root formation of tea softwood cuttings is different from that of single node cuttings. In addition to the callus at the base of cuttings, the adventitious roots are also formed in the upper cortex of softwood cuttings. In order to find out the similarities and differences between the above two types of adventitious roots of softwood cuttings and the influencing factors for the differences, an integrated analysis of plant hormones, untargeted metabolomics, and transcriptomics of the softwood cutting stems at different positions is performed. The phytohormone results show that IAA plays a leading role, and a high ratio of in vivo auxin to GA3 or ABA facilitated root formation. The ratios of IAA/GA3 and IAA/ABA in the upper and base rooting parts of cuttings are both higher than the middle non-rooting transition zone. Differences in metabolites indicate that 73 metabolites are involved in the formation of adventitious roots in cuttings. Compared with the middle non-rooting transition zone, most saccharides are downregulated in the upper and base rooting parts of softwood cuttings, and the saccharides in the base rooting parts of cuttings are more consumed than that in the upper rooting parts. Most organic acids in the callus at the base of cuttings show an upward trend, while those in the upper rooting parts show a downward trend. Furthermore, coniferyl alcohol is the key metabolite for adventitious root formation in the upper and base rooting parts of cuttings. Transcriptome results show 1099 differentially expressed genes (DEGs) are obtained, and KEGG enrichment analysis show that these DEGs are significantly enriched in phenylpropanoid biosynthesis, plant hormone signal transduction, and flavonoid biosynthesis pathways. Based on weighted gene co-expression network analysis (WGCNA), two key modules which have a highly positive correlation with IAA are identified. In summary, maintaining the balance of endogenous hormones and sufficient nutritional elements is very important for adventitious root formation in tea plants. Clarifying the material basis of softwood cutting rooting of tea plant is of great significance to improve the cutting survival rate of tea plant (especially difficult rooting varieties) and shorten the breeding cycle.

The commercial mature gallium nitride high electron mobility transistors (GaN HEMT) technology has drawn much attention for its great potential in industrial power electronic applications. GaN HEMT is known for low on-state resistance, high withstand voltage, and high switching frequency. This paper presents comparative experimental evaluations of GaN HEMT and conventional Si insulated gate bipolar transistors (Si IGBTs) of similar power rating. The comparative study is carried out on both the element and converter level. Firstly, on the discrete element level, the steady and dynamic characteristics of GaN HEMT are compared with Si-IGBT, including forward and reverse conducting character, and switching time. Then, the elemental switching losses are analyzed based on measured data. Finally, on a complementary buck converter level, the overall efficiency and EMI-related common-mode currents are compared. For the tested conditions, it is found that the GaN HEMT switching loss is much less than for the same power class IGBT. However, it is worth noting that special attention should be paid to reverse conduction losses in the PWM dead time (or dead band) of complementary-modulated converter legs. When migrating from IGBT to GaN, choosing a dead-time and negative gate drive voltage in conventional IGBT manner can make GaN reverse conducting losses high. It is suggested to use 0 V turn-off gate voltage and minimize the GaN dead time in order to make full use of the GaN advantages.

A moderate supply of aluminum (Al) can promote the root growth of plant species, such as tea, that have adapted to acid soils. The formation and development of roots are regulated by phytohormones. However, the role that phytohormones play in facilitating the beneficial effects of Al on root growth is unclear. In the present study, tea plants cultured hydroponically with either 0 or 0.4 mmol/L Al were characterized and compared in terms of root growth, hormone concentrations, and the expression of related genes. The hormone content in tea roots was measured by UPLC–MS, and the expression levels of genes involved in phytohormone biosynthesis, transport, and response were analyzed by qRT-PCR. Our results showed that the indole acetic acid (IAA) concentrations in the root base were significantly higher in plants supplied with Al compared to control plants without Al during the experimental period from 6 h to 7 d. By using inhibitors of IAA synthesis and transport, we found that Al induces short-term IAA synthesis in the root tip and enhances IAA transport in other parts of the root over the longer term, thus promoting root growth in tea plants by limiting IAA accumulation. The expression levels of genes YUC8 and AMI1, involved in IAA accumulation, were consistently upregulated in the root tip, whereas expression of PIN1/2/8, involved in IAA transport, was induced in the root base under Al supply at 6 h. In addition, the expression of PIN2 and PIN5 was highly induced in root stem by Al after 7 d and probably contributed to alleviating IAA accumulation in the root tip and thereby promoted root growth in tea plants. Meanwhile, the XET and expansin activities were increased under Al supply at 6 h. Thus, we conclude that the mechanism of Al-induced root growth is mediated by auxin accumulation and transport in cooperation with cell wall loosening in tea plants.

Quick convergence, simple implementation, and accurate estimation are essential features of realizing permanent-magnet synchronous motor (PMSM) position estimation for sensorless control using microcontrollers. A linear observer is often designed on real plant variables and is more sensitive to parameter uncertainty/variations. Thus, conventionally, a sliding mode observer (SMO)-based technique is widely used for its simplicity and convergence ability against parameter uncertainty. Although SMO has been improved for switching chattering and phase delay, it provides purely proportional gain, which leads to steady-state error and chattering in observation results. Different from conventional linear observer using real plant variables or SMO with proportional gain, a simple proportional-integral linear observer (PILO) using virtual variables is proposed in this paper. This paper also provides a comparative study with SMO. By introducing virtual variables without physical meaning, the PILO is able to simplify observer relations, get smaller phase shifts, adapt mismatched parameters, and obtain a fixed phase-shift relation. The PILO is not only simple, but also improves the estimation precision by solving the controversy between chattering and phase-delay, steady-state error. Moreover, the PILO is less sensitive to parameters mismatching. Simulation and experimental results indicate the merits of the PILO technique.