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Mosses, particularly desiccation-tolerant (DT) species, are important model organisms for studying genes involved in plant development and stress resistance. The lack of a simple and efficient stable moss transformation system has hindered progress in deciphering the genetic mechanisms underlying traits of interest in these organisms. Here, we present an Agrobacterium tumefaciens-mediated transformation system for DT mosses that uses Agrobacteriumstrain EHA105 harboring the binary vector pCAMBIA1301-GUS. This system achieved transformation efficiencies of 74% and 81% in Physcomitrium patensand Bryum argenteumprotonemata, respectively, without the need for culture and callus formation prior to regeneration. We detected GUS enzyme activity in the regenerated transgenic moss via histochemical staining. Southern blot, PCR, and RT-qPCR analyses confirmed the presence of the GUSgene. In addition, we successfully used this system to transform wild DT Syntrichia caninervis. Furthermore, P. patensand B. argenteumtransformed using this system with the stress resistance gene EsDREBfrom the desert plant Eremosparton songoricum(Litv.) exhibited improved salt tolerance. We thus present an efficient tool for the genetic analysis of DT moss species, paving the way for the development of stress-resistant crop cultivars.

Osimertinib, an orally administered third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is widely approved for the first-line and second-line treatment of advanced non-small-cell lung cancer (NSCLC) with EGFRmutations. However, the rapid development of osimertinib resistance renders the unsustainable treatment benefit. Patients with EGFR-mutated NSCLC who develop osimertinib resistance, especially those acquiring relatively rare and ‘off-target’ resistance mutations, still lack effective therapeutic options for postosimertinib therapy. Herein, we reported a 73-year-old woman diagnosed with T1N3M1 lung adenocarcinoma harboring EGFRL858R mutation, who acquired two GNASmutations (R201C and R201H) and lost the EGFRL858R mutation after progression on icotinib and osimertinib. The patient was subsequently treated with trametinib and there was no obvious tumor increase. Our study revealed that GNASR201 can confer the osimertinib resistance in EGFR-positive NSCLC, and present the first report of the prevalence of GNASR201C and R201H mutants in NSCLC which response to trametinib treatment. Our case suggests that trametinib could be a treatment option in NSCLC patients harboring GNAS-activating mutations.

The geographical region of Central Asia comprises Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, Turkmenistan, and the Xinjiang Uygur Autonomous Region of China. Central Asia’s temperate forests, steppes, and sandy deserts, including riparian tugai forests, have been identified by the World Wide Fund for Nature as Global 200 ecoregions, and the Mountains of Central Asia are considered biodiversity hotspots. Here, we describe and analyze the diverse characteristics and utilization of plant diversity and resources of the region. We confirm that there are 9520 species of higher plants, 20% of which are endemic species, belonging to 138 families and 1176 genera. The vegetation geography of Central Asia can be divided into 5 provinces and 33 districts, and more than 65% species have a Central Asian geographical distribution pattern. Plant resource utilization can be grouped into 5 categories and 31 subcategories, including food, medicine, industry, environmental protection, construction, and plant germplasm. In this review, we also discuss the principal threats to plant biodiversity in Central Asia posed by global climate change and offer recommendations for conservation strategies.

Seed germination is a key transitional stage in plant life cycle and is strongly regulated by temperature and light. Therefore, research on the effects of temperature and light on seed germination is extremely meaningful for vegetation restoration, especially in desert ecosystems. Seeds of 28 ephemeral plants collected from the Gurbantunggut Desert of China were incubated at different temperatures (5°C/1°C, 15°C/5°C, 20°C/5°C, 25°C/10°C and 30°C/15°Q in 12-h light/12-h darkness or continuous darkness regimes, and the responses of seed germination to temperature and light and the germination speed were studied in 2016. Results showed that seed germination percentage of the 28 ephemeral plants significantly differed to temperature and light. We classified the studied plants as the following groups based on their responses to temperature: 1 low temperature responsed plants, 12 moderate temperature responsed plants, 7 high temperature responsed plants, 4 non-responsed plants and 5 plants of no germination. It should be noted that Corispermum lehmannianumBunge is sensitive to moderate and high temperatures. There were 4 groups of plant in response to light, i.e., 7 light responsed plants, 10 dark responsed plants, 6 light non-responsed plants and 5 plants of no germination. Based on seed germination speed of the 28 ephemeral plants, we divided them into 4 patterns of germination, i.e., very rapid, moderately rapid, moderate and slow. Combining variations of temperature, precipitation and sand dune types in the study area, we suggested that very rapid and moderately rapid germinated plants could be used to moving sand dunes in early spring during vegetation restoration, moderate germinated plants could be used to semi-fixed sand dunes in late autumn, and slow germinated plants could be used to sand plain in summer. Thus, seedling establishment and vegetation restoration would be improved by considering seed germination characteristics of these ephemeral plants in the Gurbantunggut Desert, China.

In this paper, the finite-time synchronization problem of complex dynamic networks with time delay is studied via aperiodically intermittent control. By compared with the existed results concerning aperiodically intermittent control, some new results are obtained to guarantee the synchronization of networks in a finite time. Especially, a new lemma is proposed to reduce the convergence time. In addition, based on aperiodically intermittent control scheme, the essential condition ensuring finite-time synchronization of dynamic networks is also obtained, and the convergence time is closely related to the topological structure of networks and the maximum ratio of the rest width to the aperiodic time span. Finally, a numerical example is provided to verify the validness of the proposed theoretical results. [ABSTRACT FROM AUTHOR]

Plants have evolved complex molecular, cellular, and physiological mechanisms to respond to environmental stressors. Genetic manipulationhas represented an important potential method for improving water deficit tolerance in crops. Aldehyde dehydrogenases are involved in cellular responses to oxidative stress to protect against a variety of environmental stressors. The Syntrichia caninervisMitt. ALDH21gene plays a role in plant responses to abiotic stresses, and overexpression of this gene in tobacco (Nicoiana tabacumL.) and cotton (Gossypium hirsutumL.) decreases their sensitivity that improves tolerance to drought and salt stresses. To test the possibility that transgenic cotton constitutively expressing ScALDH21may be suitable for cultivating under water deficit conditions, phenotype, physiological response, and yield of transgenic ScALDH21cotton were measured in managed treatment plots and under field conditions. Overexpression of ScALDH21in cotton resulted in higher net photosynthetic rate, less cellular damage, more cellular protective compounds, and enhanced growth compared with nontransgenic (NT) cotton under drought stress in managed treatment plots. Yield of transgenic cottons under deficit irrigation condition was increased above that for NT plants measured under full irrigation conditions. Under field conditions, transgenic cotton yield increased ∼10.0% under full irrigation and ∼18.0% under deficit irrigation conditions compared with NT. Fiber quality of transgenic cotton lines was also improved compared with NT under both full and deficit irrigation. These results suggest that transgenic ScALDH21cotton is a viable candidate material for improving crop yields in water‐limited agricultural production systems.

Drought is a common abiotic stress that considerably limits crop production. The objective of this study is to explore the influence of water deficiency on the yield, physiologic and metabolomic attributes in upland cotton cultivars (Gossypium hirsutumL). Cotton cultivars, 'Ishonch' and 'Tashkent-6' were selected to study the relationships among their physiologic, metabolomic and yield attributes during water deficiency. Deficit irrigation was designed by modifying the traditional watering protocol to reduce water use. Results indicate that cotton cultivars respond differently to water deficit stress. Water deficit significantly influenced plant height, the number of internodes, and sympodial branches in both cultivars. However, yield components such as the number of bolls, boll seed, lint mass, and individual plant yield were significantly reduced only in 'Tashkent-6'. The leaf area decreased and the specific leaf weight increased in 'Ishonch' under deficit irrigation conditions. However, 'Tashkent-6' demonstrated significant water loss compared to 'Ishonch', and both cultivars showed reduced transpiration rates. Untargeted metabolite profiles of leaves showed clear separation in 'Ishonch', but not in 'Tashkent-6' under deficit irrigation compared to full irrigation. The individual metabolites such as proline and galactinol showed strong association with yield under water deficit stress. Moreover, this study indicates that leaf area and transpiration intensity influence yield during water deficiency. In summary, the correlation among morpho-physiologic, metabolic, and yield components significantly varied between the two cultivars under water deficiency. The flowering stage was sensitive to water stress for both cultivars. The direct relationship between physiology, metabolism, and yield may be a useful selection criterion for determining candidate parents for cotton drought tolerance breeding.

Bryum argenteumHedw. is a desiccation tolerant bryophyte and belongs to one of the most important components of the biological soil crusts (BSCs) found in the deserts of Central Asia. Limited information is available on rehydration-responsive proteins in desiccation tolerant plants. As a complement to our previous research analyzing the rehydration transcriptome, we present a parallel quantitative proteomic effort to study rehydration-responsive proteins. Bryophyte gametophores were desiccated (Dry) and rehydrated for 2 h (R2) and 24 h (R24). Proteins from Dry, R2 and R24 gametophores were labeled by isobaric tags for relative and absolute quantitation (iTRAQ) to determine the relative abundance of rehydration-responsive proteins. A total of 5503 non-redundant protein sequences were identified and 4772 (86.7%) protein sequences were annotated using Gene Ontology (GO) terms and Pfam classifications. Upon rehydration 239 proteins were elevated and 461 proteins were reduced as compared to the desiccated protein sample. Differentially up-regulated proteins were classified into a number of categories including reactive oxygen species scavenging enzymes, detoxifying enzymes, Late Embryogenesis Abundant (LEA) proteins, heat shock proteins, proteasome components and proteases, and photosynthesis and translation related proteins. Furthermore, the results of the correlation between transcriptome and proteome revealed the discordant changes in the expression between protein and mRNA.

This technical note addresses the problem of high gain observer design for a class of triangular nonlinear systems with sampled and delayed output measurements. The transmission delay may be larger or smaller than the sampling period. Firstly, a class of hybrid systems are introduced, and sufficient conditions are proposed to guarantee that the hybrid systems are globally and exponentially stable. Then, a continuous-discrete observer is designed for the nonlinear systems. Based on these sufficient conditions and a specially constructed Lyapunov-Krasovskii functional, it is shown that the observation errors globally and exponentially converge to the origin. Finally, an illustrative example is used to verify the validity of the proposed design methods. [ABSTRACT FROM AUTHOR]

We design observers for nonlinear systems with sampled and delayed output measurements. The observers are of continuous and hybrid in nature. Based on an auxiliary integral technique, the exponential stability of the estimation errors is achieved, and the sampling period and the maximum delay are also given. Finally, numerical examples are provided to illustrate the design methods.

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