Low-PMEPR Preamble Sequence Design for Dynamic Spectrum Allocation in OFDMA Systems

Orthogonal Frequency Division Multiple Access (OFDMA) with Dynamic spectrum allocation (DSA) is able to provide a wide range of data rate requirements. This paper is focused on the design of preamble sequences in OFDMA systems with low peak-to-mean envelope power ratio (PMEPR) property in the context of DSA. We propose a systematic preamble sequence design which gives rise to low PMEPR for possibly non-contiguous spectrum allocations. With the aid of Golay-Davis-Jedwab (GDJ) sequences, two classes of preamble sequences are presented. We prove that their PMEPRs are upper bounded by 4 for any DSA over a chunk of four contiguous resource blocks

An Enhanced Drought-Tolerant Method Using SA-Loaded PAMPS Polymer Materials Applied on Tobacco Pelleted Seeds

Drought is one of the most important stress factors limiting the seed industry and crop production. Present study was undertaken to create novel drought-resistant pelleted seeds using the combined materials with superabsorbent polymer, poly(2-acrylamide-2-methyl propane sulfonic acid) (PAMPS) hydrogel, and drought resistance agent, salicylic acid (SA). The optimized PAMPS hydrogel was obtained as the molar ratio of 2-acrylamido-2-methyl-propanesulfonic acid (AMPS) to potassium peroxydisulfate (KPS) and N, N′-methylene-bis-acrylamide (MBA) was 1 : 0.00046 : 0.00134. The hydrogel weight after swelling in deionized water for 24 h reached 4306 times its own dry weight. The water retention ratio (RR) of PAMPS was significantly higher as compared with the control. It could keep as high as 85.3% of original weight after 30 min at 110°C; even at 25°C for 40 d, the PAMPS still kept RR at 33.67%. PAMPS disintegration ratio increased gradually and reached around 30% after embedding in soil or activated sludge for 60 d. In addition, there were better seed germination performance and seedling growth in the pelleted treatments with SA-loaded PAMPS hydrogel under drought stress than control. It suggested that SA-loaded PAMPS hydrogel, a nontoxic superabsorbent polymer, could be used as an effective drought resistance material applied to tobacco pelleted seeds

Screening of rice cultivars for Cr-stress response by using the parameters of seed germination, morpho-physiological and antioxidant analysis

Rice is the most important crop for the majority of population across the world with sensitive behavior toward heavy metals such as chromium (Cr) in polluted regions. Although, there is no information on the Cr resistance phenotyping in rice. Herein, two different groups of rice cultivars (normal, and hybrid) were used, each group with 14 different rice cultivars. Firstly, seed germination analysis was conducted by evaluating various seed germination indices to identify the rice cultivars with greatest seed germination vigor. Furthermore, exposure of chromium (Cr) toxicity to 28 different rice varieties (NV1-NV14, HV1-HV14) caused noticeable plant biomass reduction. Subsequently, NV2, NV6, NV10, NV12, NV13 (normal type), HV1, HV4, HV8, and HV9 (hybrid types) were pragmatic as moderately sensitive varieties, while NV3, NV4, NV9, and NV14 (normal type), HV3, HV6, HV7, and HV13 were observed as moderately tolerant. Although, NV7, and HV10 were ranked most sensitive cultivars, and NV11, and HV14 were considered as most tolerant varieties as compared to the other rice (both groups) genotypes. Afterward, Cr induced reduction in chlorophyll pigments were significantly lesser in HV14 relative to NV11, NV7, and especially HV10, and as a result HV14 modulated the total soluble sugar level as well as reduced ROS accumulation, and MDA contents production by stimulating the antioxidant defense mechanism conspicuously which further reduced the electrolyte leakage as well. Our outcomes provide support to explore the Cr tolerance mechanism in cereal crops as well as knowledge about rice breeding with increased tolerance against Cr stress.This research was supported by National Natural Science Foundation of China (No. 32072127), Zhejiang Provincial Natural Science Foundation (No. LY21C130006), Dabeinong Funds for Discipline Development and Talent Training in Zhejiang University, Collaborative Innovation Center for Modern Crop Production co-sponsored by Province and Ministry (CIC-MCP) and Zhenjiang International-joint fund (No. GJ2020010). The authors would like to extend their sincere appreciation to the Researchers Supporting Project Number (RSP-2021/168), King Saud University, Riyadh, Saudi Arabia

Reactive Oxygen Species and Gibberellin Acid Mutual Induction to Regulate Tobacco Seed Germination

Seed germination is a complex process controlled by various mechanisms. To examine the potential contribution of reactive oxygen species (ROS) and gibberellin acid (GA) in regulating seed germination, diphenylene iodonium chloride (DPI) and uniconazole (Uni), as hydrogen peroxide (H2O2) and GA synthesis inhibitor, respectively, were exogenously applied on tobacco seeds using the seed priming method. Seed priming with DPI or Uni decreased germination percentage as compared with priming with H2O, especially the DPI + Uni combination. H2O2 and GA completely reversed the inhibition caused by DPI or Uni. The germination percentages with H2O2 + Uni and GA + DPI combinations kept the same level as with H2O. Meanwhile, GA or H2O2 increased GA content and deceased ABA content through corresponding gene expressions involving homeostasis and signal transduction. In addition, the activation of storage reserve mobilization and the enhancement of soluble sugar content and isocitrate lyase (ICL) activity were also induced by GA or H2O2. These results strongly suggested that H2O2 and GA were essential for tobacco seed germination and by downregulating the ABA/GA ratio and inducing reserve composition mobilization mutually promoted seed germination. Meanwhile, ICL activity was jointly enhanced by a lower ABA/GA ratio and a higher ROS concentration

Establishing an Efficient Way to Utilize the Drought Resistance Germplasm Population in Wheat

Drought resistance breeding provides a hopeful way to improve yield and quality of wheat in arid and semiarid regions. Constructing core collection is an efficient way to evaluate and utilize drought-resistant germplasm resources in wheat. In the present research, 1,683 wheat varieties were divided into five germplasm groups (high resistant, HR; resistant, R; moderate resistant, MR; susceptible, S; and high susceptible, HS). The least distance stepwise sampling (LDSS) method was adopted to select core accessions. Six commonly used genetic distances (Euclidean distance, Euclid; Standardized Euclidean distance, Seuclid; Mahalanobis distance, Mahal; Manhattan distance, Manhat; Cosine distance, Cosine; and Correlation distance, Correlation) were used to assess genetic distances among accessions. Unweighted pair-group average (UPGMA) method was used to perform hierarchical cluster analysis. Coincidence rate of range (CR) and variable rate of coefficient of variation (VR) were adopted to evaluate the representativeness of the core collection. A method for selecting the ideal constructing strategy was suggested in the present research. A wheat core collection for the drought resistance breeding programs was constructed by the strategy selected in the present research. The principal component analysis showed that the genetic diversity was well preserved in that core collection

Acetylation Targets the M2 Isoform of Pyruvate Kinase for Degradation through Chaperone-Mediated Autophagy and Promotes Tumor Growth

Most tumor cells take up more glucose than normal cells but metabolize glucose via glycolysis even in the presence of normal levels of oxygen, a phenomenon known as the Warburg effect. Tumor cells commonly express the embryonic M2 isoform of pyruvate kinase (PKM2) that may contribute to the metabolism shift from oxidative phosphorylation to aerobic glycolysis and tumorigenesis. Here we show that PKM2 is acetylated on lysine 305 and that this acetylation is stimulated by high glucose concentration. PKM2 K305 acetylation decreases PKM2 enzyme activity and promotes its lysosomal-dependent degradation via chaperone-mediated autophagy (CMA). Acetylation increases PKM2 interaction with HSC70, a chaperone for CMA, and association with lysosomes. Ectopic expression of an acetylation mimetic K305Q mutant accumulates glycolytic intermediates and promotes cell proliferation and tumor growth. These results reveal an acetylation regulation of pyruvate kinase and the link between lysine acetylation and CMA

Preparation of MXene cellulose composite films and their adsorption properties for methylene blue

Mxenes is a kind of inorganic 2D dimensional nano materials with novel structure. It is composed of transition metal carbides, nitrides or carbonitrides with several atomic layers. At present, mxenes are widely used in the fields of energy, optics, catalysis, adsorption and so on. Because of its high hydrophilicity, large specific surface area, negative surface charge and high ion exchange capacity, it is used as an excellent adsorbent material. Mxenes materials will remove heavy metal ions and radioactive elements in the environment through electrostatic attraction, coordination chelation and other interactions. It is expected to become an ideal carrier for adsorbing heavy metal ions and radioactive. In this experiment, the property of adsorption of MXene is used. It is used to modified the surface of a cotton to make a filter cloth. There are also another liquids used in this experiment to modify the surface of the filter cloth which have some useful functional group. While the MXene play the most important role in this experiment. By using immersing method, the end product shows it is play a role in purify mythlene blue liquid. Besides, even though there is some other pollutes in waste water of industry, MXene is a good adsorbent to absorb other heavy metal ions in terms of in this experiment only the adsorption of dyestuff has been tested

Acupuncture in improving endometrial receptivity: a systematic review and meta-analysis

Abstract Background This systematic review aimed at summarizing and evaluating the evidence of randomized controlled trials (RCTs) using acupuncture to improve endometrial receptivity (ER). Methods We searched 12 databases electronically through August 2018 without language restrictions. We included RCTs of women of infertility due to low ER, and excluded infertility caused by other reasons or non-RCTs. Two independent reviewers extracted the characteristics of studies and resolved the differences through consensus. Data were pooled and expressed as standard mean difference (SMD) or mean difference (MD) for continuous outcomes and risk ratio (RR) for dichotomous outcomes, with 95% confidence interval (CI). Results We found very low to moderate level of evidence that acupuncture may improve pregnancy rate (RR = 1.23 95%CI[1.13, 1.34] P < 0.00001) and embryo transfer rate (RR = 2.04 95%CI[1.13, 3.70] P = 0.02), increase trilinear endometrium (RR = 1.47 95%CI [1.27, 1.70] P < 0.00001), thicken endometrium (SMD = 0.41 95% CI [0.11, 0.72] P = 0.008), reduce resistive index (RI) (MD = -0.08 95% CI [− 0.15, − 0.02] P = 0.01), pulse index (PI) (SMD = -2.39 95% CI [− 3.85, − 0.93] P = 0.001) and peak systolic velocity/ end-diastolic blood velocity (S/D) (SMD = -0.60 95% CI [− 0.89, − 0.30] P < 0.0001), compared with medication, sham acupuncture or physiotherapy. Acupuncture was statistically significant as a treatment approach. Conclusion The efficacy and safety of acupuncture on key outcomes in women with low ER is statistically significant, but the level of most evidence was very low or low. More large-scale, long-term RCTs with rigorous methodologies are needed

Physical properties and in vitro starch digestibility of noodles substituted with Tartary buckwheat flour

The effects of Tartary buckwheat flour (TBF)/wheat flour ratio on the physical properties, and starch digestion, of noodles are investigated. Incorporation of TBF significantly changes the physical character of noodles. As TBF levels increase in noodles, the color of dough sheet become darker and noodle texture is affected deleteriously. Starch gelatinization temperature increases with TBF inclusion, and the relaxation time by low-field nuclear magnetic resonance (LF-NMR) system (including T₂₁, T₂₂, and T₂₃) decreases due to the close combination of water with macromolecule such as protein and starch. Near-infrared reflectance spectroscopy (NIRS) results in all of the cooked noodles show that both energy, and protein content, decrease significantly. Compared with noodles without substitution, TBF noodles reduce the production of reducing sugar released during an in vitro starch digestion. These findings suggest that incorporation of TBF in noodles could improve noodle nutrition but care is required to ensure appropriate textural characteristics are maintained