Hydrogen sulfide (H2S), a small gaseous signaling molecule, regulates antioxidase activity and improves plant tolerance to oxidative stress. The phytotoxic effect of Copper Oxide (II) nanoparticles ...(CuO NPs) is due to oxidative stress. Here, we show that H2S-mediated persulfidation of antioxidase is essential for an effective stress response of tomato exposed to CuO NPs. The CuO NP-induced increase in hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels was significantly reduced by treatment with the H2S donor NaHS. In vivo, NaHS increased superoxide dismutase (SOD), ascorbate peroxidase (APX) and peroxidase (POD) activities under CuO NP stress. In vitro, NaHS increased APX and POD activities but decreased catalase (CAT) activity. Persulfidation existed in recombinant SlCAT1, SlcAPX1 and SlPOD5 proteins. The persulfidatied cysteine (Cys) residues were verified by liquid chromatography–tandem mass spectrometry (LC-MS/MS), revealing their position on the protein surface. Cys234 of SlCAT1 is located in the immune-responsive domain and close to the enzyme activity domain. Cys234 of SlcAPX1 and Cys 61 SlPOD5 are located in the enzyme activity domain. Persulfidation increased SlcAPX1 and SlPOD5 activities but decreased SlCAT1 activity. These data indicate that H2S-mediated persulfidation posttranslationally regulates the activities of CAT, APX and POD, thereby enhancing the plant's response to oxidative stress. Additionally, this work provides an experimental approach for the study of persulfidation in plants.
•Persulfidation exists in the antioxidase of tomato cells.•The persulfidated sites locate on protein surface and in the enzyme activity domain.•H2S increases the persulfidation level of recombinant SlCAT1, SlcAPX1 and SlPOD5 in a dose-dependent manner.•Persulfidation regulates the recombinant SlCAT1, SlcAPX1 and SlPOD5 activities.
Hydrogen sulfide (H2S) signaling has been considered a key regulator of plant developmental processes and defenses. In this study, we demonstrate that high levels of H2S inhibit auxin transport and ...lead to alterations in root system development. H2S inhibits auxin transport by altering the polar subcellular distribution of PIN proteins. The vesicle trafficking and distribution of the PIN proteins are an actin-dependent process. H2S changes the expression of several actin-binding proteins (ABPs) and decreases the occupancy percentage of F-actin bundles in the Arabidopsis roots. We observed the effects of H2S on F-actin in T-DNA insertion mutants of cpa, cpb and prf3, indicating that the effects of H2S on F-actin are partially removed in the mutant plants. Thus, these data imply that the ABPs act as downstream effectors of the H2S signal and thereby regulate the assembly and depolymerization of F-actin in root cells. Taken together, our data suggest that the existence of a tightly regulated intertwined signaling network between auxin, H2S and actin that controls root system development. In the proposed process, H2S plays an important role in modulating auxin transport by an actin-dependent method, which results in alterations in root development in Arabidopsis.
The objective of this paper is to prepare a series of spherical NiCo2S4 materials coated with N-doped C (NiCo2S4/NC-400 °C, NiCo2S4/NC-450 °C and NiCo2S4/NC-500 °C) by calcining the precursor of ...NiCo-MOF (metal organic framework) at different temperatures, and to explore the applications as anode materials for lithium-ion batteries. The results showed that the electrochemical reaction mechanism of the three materials is conversion reaction. Compared with NiCo2S4/NC-400 °C and NiCo2S4/NC-450 °C, NiCo2S4/NC-500 °C exhibited excellent cycle performance and rate performance at different current densities. NiCo2S4/NC-500 °C has a minimum charge transfer resistance. In addition, the pseudocapacitance contribution rate was 67.1 % at the scanning speed of 0.5 mV s−1, as well as relatively good structural characteristics and small particle size. The results of this study provide a reference for the application of NiCo2S4/NC materials in lithium-ion batteries.
Temporal and spatial distribution and characteristics of surface water and groundwater have greatly changed under the impacts of climate change and human activities in the middle reaches of the Heihe ...River. Study the evolution of water system and the mechanisms driving the change are critical for sustainable water management of the river basins. Based on groundwater levels of the monitoring wells and hydrogeological data, meteorological data, remote-sensing data and statistical irrigation data, variation of groundwater level caused by surface water allocation was studied in the middle reaches of the Heihe River in the past 30 years. Results show that the unbalanced allocation of surface water and cropland expansion have resulted in the over-abstraction of groundwater and then lowered the groundwater table and renewable quantity. Groundwater level had declined in 1985-2004, and had declined and risen again during 2005-2013. The lowering groundwater level had reached a maximum of 17.41 m in the upper and middle
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•Prepared new conductive MXene-based hydrogel.•Improved the oxidative stability and preventing accumulation of MXene.•Composite hydrogel exhibits high stretchability, skin-like ...softness and high toughness.•Monitor weak electrophysiological signals and achieve sign language translation and eye tracking.
Epidermal sensors capable of monitoring various physical signals are vital in wearable healthcare applications. MXene-based conductive hydrogels have become promising candidates as skin-attachable sensors for these purposes. However, due to the easy oxidation and weak combination of MXene nanosheets with network matrix, it remains challenging to construct a mechanically tough, highly conductive and skin-conformal hydrogel for reliable signal recording (especially weak electrophysiological signals). Herein, a new conductive MXene-based hydrogel is fabricated through introducing silk fibroin (SF)-modified MXene (MXene-SF) into polyacrylamide (PAM) network. It is demonstrated that the encapsulation of SF on MXene surfaces greatly improves its stability, and meanwhile induces the formation of multiple noncovalent interactions between MXene-SF and PAM chains. The resulting hydrogel exhibits high stretchability (1560 %), remarkable toughness (165 kJ/m3), high conductivity (0.25 S/m) and self-adhesion. This hydrogel is high-sensitive in a large strain range for detecting various human motions. Especially, the high conformal adhesion and low interface impedance make the hydrogel bioelectrodes precisely monitor weak electrophysiological signals (e.g. electromyogram and electrooculogram), successfully achieving sign language translation and eye tracking. Additionally, the hydrogel has great thermosensitive capacities for body temperature monitoring. This study provides a general strategy for designing MXene-based hydrogels with tailored functionalities as flexible electronics.
Novel 3D-WPP algorithms for parallel HEVC encoding Wen, Ziyu; Quo, Bichuan; Liu, Jiashuo ...
2016 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP),
03/2016
Conference Proceeding, Journal Article
Although wavefront parallel processing (WPP) proposed in the HEVC standard and various inter frame WPP algorithms can achieve comparatively high parallelism, their scalability for its parallelism is ...still very limited due to various dependencies introduced in spatial and temporal prediction in HEVC. In this paper, we propose three types of 3 Dimensional WPP (3D-WPP) algorithms that can significantly improve the parallelism, while achieving good tradeoffs between implementation complexity, determinism, and rate-distortion (RD) performance. Experimental results show that the proposed algorithms can lead to up to 2.8 × speed up compared with existing inter frame WPP methods. While the Simple 3D-WPP and Static 3D-, WPP algorithm may introduce an BD rate loss between 0 to 4.9% as compared with existing algorithms, the more complex Dynamic 3D-WPP algorithm achieves better parallelism with virtually no coding performance loss.
Hydrogen sulfide (H
2
S) and hydrogen peroxide (H
2
O
2
) function as the signaling molecules in plants responding to salt stresses. The present study presents a signaling network involving H
2
S and ...H
2
O
2
in salt resistance pathway of the
Arabidopsis
root.
Arabidopsis
roots were sensitive to 100 mM NaCl treatment, which displayed a great increase in electrolyte leakage (EL) and Na
+
/K
+
ratio under salt stress. The treatment of H
2
S donors sodium hydrosulfide (NaHS) enhanced the salt tolerance by maintaining a lower Na
+
/K
+
ratio. In addition, the inhibition of root growth under salt stress was removed by H
2
S. Further studies indicated that H
2
O
2
was involved in H
2
S-induced salt tolerance pathway. H
2
S induced the production of the endogenous H
2
O
2
via regulating the activities of glucose-6-phosphate dehydrogenase (G6PDH) and plasma membrane (PM) NADPH oxidase, with the treatment with dimethylthiourea (DMTU, an ROS scavenger), diphenylene iodonium (DPI, a PM NADPH oxidase inhibitor), or glycerol (G6PDH inhibitor) removing the effect of H
2
S. Treatment with amiloride (an inhibitor of PM Na
+
/H
+
antiporter) and vanadate (an inhibitor of PM H
+
-ATPase) also inhibited the activity of H
2
S on Na
+
/K
+
ratio. Through an analysis of quantitative real-time polymerase chain reaction and Western blot, we found that H
2
S promoted the genes expression and the phosphorylation level of PM H
+
-ATPase and Na
+
/H
+
antiporter protein level. However, when the endogenous H
2
O
2
level was inhibited by DPI or DMTU, the effect of H
2
S on the PM Na
+
/H
+
antiporter system was removed. Taken together, H
2
S maintains ion homeostasis in the H
2
O
2
-dependent manner in salt-stress
Arabidopsis
root.
Hydrogen sulfide (H2S), which was previously considered to be toxic, is now regarded as a burgeoning endogenous gaseous transmitter. H2S plays a vital role in the mechanism of response/adaptation to ...adverse environmental conditions as well as crosstalk with other signaling molecules, including ROS, by affecting the corresponding gene expression and subsequent enzyme activities. Both H2S and ROS are potent signaling molecules that can provoke reversible and irreversible oxidative post-translational modifications on cysteine residues of proteins such as sulfenylation or persulfidation, affecting the redox status and function of the target proteins. The dynamic interplay between persulfidation and sulfenylation occurring on cysteine residues is of great importance in response to environmental changes.The present Special Issue of IJMS has the aim of providing the most current findings on the function of signaling molecules, including H2S and ROS, in higher plants, and it is open to different types of manuscripts, including original research papers, perspectives, or reviews where either ROS, H2S, or related molecules could be involved at the biochemical or physiological levels.
Multiplicative Extended Kalman Filter (MEKF) is one of the most widely used satellite attitude estimation methods. However, the linearization errorʼs influence is an inherent limitation of this ...method. In this paper, we aim to analyze this linearization error in the typical satellite attitude determination system with star sensors and gyros. The formulation of linearization error is first derived and the curvature metric is then employed to measure the linearization error. Additionally, we show the reason why linearization error has influence on the performance of MEKF. Based on these analyses, we point out that star sensorsʼ sampling frequency, initial estimated error and accuracy of gyroʼs measurement model are the factors that could enlarge the system modelʼs linearization error. They all affect the linearization error and attitude determination accuracy by decreasing the predicted accuracy. More concretely, the influence of star sensorʼs sampling frequency is large, while initial estimated error and gyroʼs measurement error within a certain range have little influence on MEKF. Finally, combined with plenty of experiments, validity of the above analyses is verified.
Based on the measured and surveyed hydrologic data of the Shule River basin, Hexi Corridor from 1956 to 2013, monthly and annual variations of mountain runoffs of the trunk streams of the Shule River ...were statistically analyzed, and Kandel rank correlation method was used to inspect runoff variation in the basin. The results show that the mountain runoff averaged over 1956-2013 is 11.6679x108 m3; floods concentrate from June to September, when the runoff accounts for 35.9%~78.7% of the annual runoff; groundwater recharge accounts for 40.46% of the runoff on the average; annual variation of the mountain runoff is continuously increasing with a relatively small rate. It is predicted that in the next 5 years (2014-2018) the annual average mountain runoff of the trunk streams of the Shule River would increase to 13.01x108 m3.
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