Tissue culture and transformation of introducing genes useful for pest management in rice

Sheath blight (SB), caused by Rhizoctonia solani K¨¹hn, is a major rice disease internationally and in the southern rice area of the Unites States, including Louisiana. Breeders have incorporated partial resistance into commercial rice varieties to control the disease, but a higher level of resistance is needed. It has been demonstrated that the pathogenesis-related (PR) proteins ¦Â-1, 3-glucanase and chitinase are components of effective defense mechanisms for protecting plants against fungal pathogens. This research was conducted to co-transform the ¦Â-1, 3-glucanase, chitinase and bar genes into the rice variety Taipei 309 using the hpt gene for resistance to hygromycin B as a selective marker. Transformed calli and regenerated plants were screened with hygromycin B, and the plants were then further tested for resistance to Liberty herbicide and Rhizoctonia solani. Methods were developed to screen transgenic plants for resistance to hygromycin B and Liberty herbicide using dip and cut in toxicant solutions. Five of 99 plants in the field test and 51 of 55 plants in greenhouse test were highly resistant to Liberty herbicide. The tooth-pick inoculation method was used to test transformed plants for SB resistance. Seventeen transgenic plants in the field test and 10 transgenic plants from greenhouse tests were highly resistant to SB. Fourteen of the17 SB resistant plants were also resistant to hygromycin B, one of the plants was highly resistant to Liberty herbicide, and 9 of the 17 SB resistant plants had moderate resistance to Liberty. Panicle blight, caused by Burkholderia glumae, has been an important bacterial disease in rice worldwide and in Louisiana. No effective pesticides are available to control this disease. The PR protein thionin is reported to control certain bacterial diseases in plants. In this study, the thionin production, bar, and hpt genes were co-transformed to the rice variety Lafitte. Resistance to hygromycin B, Liberty herbicide, Xanthomonas oryza and B. glumae were expressed in selected transformed Lafitte plants. This research has created, through transformation, new sources of resistance to two major rice pathogens that cause major losses to rice. These resistances can be transferred to commercial varieties by conventional breeding methods

Limits to growth of forest biomass carbon sink under climate change.

Widely recognized as a significant carbon sink, North American forests have experienced a history of recovery and are facing an uncertain future. This growing carbon sink is dictated by recovery from land-use change, with growth trajectory modified by environmental change. To address both processes, we compiled a forest inventory dataset from North America to quantify aboveground biomass growth with stand age across forest types and climate gradients. Here we show, the biomass grows from 90 Mg ha-1 (2000-2016) to 105 Mg ha-1 (2020 s), 128 Mg ha-1 (2050 s), and 146 Mg ha-1 (2080 s) under climate change scenarios with no further disturbances. Climate change modifies the forest recovery trajectory to some extent, but the overall growth is limited, showing signs of biomass saturation. The future (2080s) biomass will only sequester at most 22% more carbon than the current level. Given such a strong sink has limited growth potential, our ground-based analysis suggests policy changes to sustain the carbon sink

An exact solution of spherical mean-field plus orbit-dependent non-separable pairing model with two non-degenerate j-orbits

An exact solution of nuclear spherical mean-field plus orbit-dependent non-separable pairing model with two non-degenerate j-orbits is presented. The extended one-variable Heine-Stieltjes polynomials associated to the Bethe ansatz equations of the solution are determined, of which the sets of the zeros give the solution of the model, and can be determined relatively easily. A comparison of the solution to that of the standard pairing interaction with constant interaction strength among pairs in any orbit is made. It is shown that the overlaps of eigenstates of the model with those of the standard pairing model are always large, especially for the ground and the first excited state. However, the quantum phase crossover in the non-separable pairing model cannot be accounted for by the standard pairing interaction.Comment: 5 pages, 1 figure, LaTe

The Characteristics of Mechanical Grinding on Kaolinite Structure and Thermal Behavior

AbstractThe relationship between kaolinite structure and the temperature of thermal transformation of phase was discussed in this paper through grinding and heating treatment. The results show that the structure of kaolinite is destroyed rapidly with increasing mechanical grinding time, and the kaolinite structure collapses completely after 1h grinding. The temperature of thermal transformation of phase decreases with the destruction of kaolinite structure. This result has a great significance for the utilization of kaolinite associated with coal measures in China

Probabilistic Prediction of Longitudinal Trajectory Considering Driving Heterogeneity with Interpretability

Automated vehicles are envisioned to navigate safely in complex mixed-traffic scenarios alongside human-driven vehicles. To promise a high degree of safety, accurately predicting the maneuvers of surrounding vehicles and their future positions is a critical task and attracts much attention. However, most existing studies focused on reasoning about positional information based on objective historical trajectories without fully considering the heterogeneity of driving behaviors. Therefore, this study proposes a trajectory prediction framework that combines Mixture Density Networks (MDN) and considers the driving heterogeneity to provide probabilistic and personalized predictions. Specifically, based on a certain length of historical trajectory data, the situation-specific driving preferences of each driver are identified, where key driving behavior feature vectors are extracted to characterize heterogeneity in driving behavior among different drivers. With the inputs of the short-term historical trajectory data and key driving behavior feature vectors, a probabilistic LSTMMD-DBV model combined with LSTM-based encoder-decoder networks and MDN layers is utilized to carry out personalized predictions. Finally, the SHapley Additive exPlanations (SHAP) method is employed to interpret the trained model for predictions. The proposed framework is tested based on a wide-range vehicle trajectory dataset. The results indicate that the proposed model can generate probabilistic future trajectories with remarkably improved predictions compared to existing benchmark models. Moreover, the results confirm that the additional input of driving behavior feature vectors representing the heterogeneity of driving behavior could provide more information and thus contribute to improving the prediction accuracy.Comment: 14 pages, 8 figure

Pročišćavanje i karakterizacija fibrinolitičkog enzima iz plijesni Rhizopus microsporus var. tuberosus

Extracellular fibrinolytic enzyme from Rhizopus microsporus var. tuberosus was purified and characterised. The microorganism was isolated in a distillery from daqu, a fermentative agent used in the production of Chinese liquor and vinegar at diff erent temperatures. The fibrinolytic enzyme was partially purifi ed by ammonium sulphate precipitation, dialysis, DEAE Sepharose® Fast Flow ion exchange chromatography and Sephadex G-75 gel filtration chromatography. The molecular mass of the fi brinolytic enzyme was estimated to be 24.5 kDa by SDS-PAGE. The purified enzyme showed optimal activity at pH=7.0 and 37 °C by fibrin plate method. It showed stronger resistance to the inhibition by trypsin and was stable at 37 °C retaining 96.1 % residual activity aft er 4 h of incubation. The fibrinolytic activity of the enzyme was enhanced by Na+, Ca2+, Mg2+ and Mn2+. Conversely, Zn2+ and Cu2+ partly inhibited enzymatic activity. Using fibrin plate method, we found that the enzyme not only degrades fibrin directly, but also activates plasminogen into plasmin to degrade fibrin. The results indicate that the pure enzyme has a potential in dissolving blood clot, and the possibility for application in the treatment of thrombosis.U radu je pročišćen i ispitan izvanstanični fibrinolitički enzim iz plijesni Rhizopus microsporus var. tuberosus. Mikroorganizam je izoliran u distileriji iz starter kulture koja se koristi za fermentaciju tradicionalnog kineskog likera i octa pri različitim temperaturama, tzv. daqu. Fibrinolitički je enzim djelomično pročišćen taloženjem pomoću amonijevog sulfata, dijalizom, ionskom kromatografijom na koloni DEAE Sepharose Fast Flow i gel-filtracijskom kromatografijom na koloni Sephadex G-7. Molekularna masa fibrinolitičkog enzima, određena pomoću SDS-PAGE, iznosila je 24,5 kDa. Optimalni uvjeti za aktivnost pročišćenog enzima bili su pH=7,0 i 37 °C. Enzim je bio otporan na inhibiciju tripsinom, stabilan pri 37 °C, te je zadržao 96,1 % aktivnosti nakon 4 sata inkubacije. Fibrinolitička se aktivnost enzima pojačala u prisutnosti iona Na+, Ca2+, Mg2+ i Mn2+, dok su ioni Zn2+ i Cu2+ djelomično inhibirali njegovu aktivnost. Utvrđeno je da enzim izravno razgrađuje fibrin, i aktivira plazminogen, pri čemu nastali plazmin razgrađuje fibrin. Rezultati pokazuju da se pročišćeni enzim može primijeniti u liječenju tromboze, jer ima sposobnost razgradnje krvnih ugrušaka

Transpiration Dominates Ecosystem Water‐Use Efficiency in Response to Warming in an Alpine Meadow

As a key linkage of C and water cycles, water‐use efficiency (WUE) quantifies how much water an ecosystem uses for carbon gain. Although ecosystem C and water fluxes have been intensively studied, yet it remains unclear how ecosystem WUE responds to climate warming and which processes dominate the response of WUE. To answer these questions, we examined canopy WUE (WUEc), ecosystem WUE (WUEe) and their components including gross ecosystem productivity, ecosystem evapotranspiration (ET), soil evaporation (E), and plant canopy transpiration (T), in response to warming in an alpine meadow by using a manipulative warming experiment in 2015 and 2016. As expected, low‐ and high‐level warming treatments increased soil temperature (Tsoil) at 10 cm on average by 1.65 and 2.77°C, but decreased soil moisture (Msoil) by 2.52 and 7.6 vol %, respectively, across the two years. Low‐ and high‐level warming increased WUEe by 7.7 and 9.3% over the two years, but rarely changed WUEc in either year. T/ET ratio determined the differential responses of WUEc and WUEe. Larger T/ET led to less difference between WUEc and WUEe. By partitioning WUEc and WUEe into different carbon and water fluxes, we found that T rather than gross ecosystem productivity or E dominated the responses of WUEc and WUEe to warming. This study provides empirical insights into how ecosystem WUE responds to warming and illustrates the importance of plant transpiration in regulating ecosystem WUE under future climate change

γ -soft rotor with configuration mixing in the O(6) limit of the interacting boson model

To describe obvious intruder states and nonzero quadrupole moments of γ-soft nuclei such as Pt194, a rotor extension plus intruder configuration mixing with 2n-particle and 2n-hole configurations from n=0 up to n→ in the O(6) (γ-unstable) limit of the interacting boson model is proposed. It is shown that the configuration mixing scheme keeps the lower part of the γ-unstable spectrum unchanged and generates the intruder states due to the mixing. It is further shown that almost all low-lying levels below 2.17 MeV in Pt194 can be well described by modifying the O(6) quadrupole-quadrupole interaction into an exponential form. The third-order term needed for a rotor realization in the interacting boson model seems necessary to produce nonzero quadrupole moments with the correct sign

Characterization of EndoTT, a novel single-stranded DNA-specific endonuclease from Thermoanaerobacter tengcongensis

EndoTT encoded by tte0829 of Thermoanaerobacter tengcongensis binds and cleaves single-stranded (ss) and damaged double-stranded (ds) DNA in vitro as well as binding dsDNA. In the presence of a low concentration of NaCl, EndoTT cleaved ss regions of damaged dsDNA efficiently but did not cleave DNA that was entirely ss or ds. At high concentrations of NaCl or MgCl2 or ATP, there was also specific cleavage of ssDNA. This suggested a preference for ss/ds junctions to stimulate cleavage of the DNA substrates. EndoTT has six specific sites (a–f) in the oriC region (1–70 nt) of T. tengcongensis. Substitutions of nucleotides around site c prevented cleavage by EndoTT of both sites c and d, implying that the cleavage specificity may depend on both the nucleotide sequence and the secondary structure of the ssDNA. A C-terminal sub-fragment of EndoTT (residues 107–216) had both endonucleolytic and DNA-binding activity, whereas an N-terminal sub-fragment (residues 1–110) displayed only ssDNA-binding activity. Site-directed mutations showed that G170, R172 and G177 are required for the endonuclease activity of EndoTT, but not for DNA-binding, whereas D171, R178 and G189 are partially required for the DNA-binding activity

Anti-inflammatory effects of Fritillaria ussuriensis maxim

Bulbs of Fritillaria ussuriensis Maxim., usually known as Bulbus Fritillariae ussuriensis, (BFU) has been used as antitussive, antiasthmatic and expectorant in traditional herbal medicine. In this study, the aqueous extract of BFU (BFUE) was evaluated for its anti-inflammatory activity. Meanwhile, the content of PGE2 and MDA in inflammatory exudates was measured to explore the anti-inflammatory mechanisms of BFUE. In order to identify the active components of BFU, the total alkaloids (TA), the total flavonoids (TF) and the total saponins (TS) were evaluated for their bioactivities. Results showed that BFUE inhibited carrageenin-induced paw edema, xylene-induced auricular edema and acetic acid-induced vascular permeation in a dose-dependent manner, and it revealed obvious inhibitory effects on the increase of PGE2 and MDA. TF showed the highest anti-inflammatory effects on auricular edema induced by xylene in mice, and TS at a dose of 400 and 200 mg/kg also showed good effects (P 2 and MDA levels, and TF and TS might be the active components for this activity.Colegio de Farmacéuticos de la Provincia de Buenos Aire