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Total least squares estimation based on Gauss–Newton method in nonlinear errors-in-variables (NEIV) model will encounter the problems of convergence, correctness and accuracy of solution related to the selected initial parameter values. In this contribution, a new total least squares estimator is introduced to solve NEIV model. This method is an extension of the homotopy nonlinear weighted least square (HNWLS) method, which is used in the nonlinear Gauss–Markov model where only the dependent variables contain random errors. The new estimator is called homotopy nonlinear weighted total least squares (HNWTLS), because it adopts weighted total least squares adjustment criterion and homotopy method to estimate nonlinear model parameters. The homotopy function of HNWTLS is constructed by using the normal equation of weighted total least squares adjustment criterion. By taking the error vector of independent variables as a parameter vector, the NEIV model is transformed into a classical nonlinear adjustment model. Then, according to the conclusion of HNWLS, the calculation formula of HNWTLS is derived, and the corresponding calculation algorithm is developed accordingly, where the standard Euler prediction and Newton correction method are introduced into it to tracks the homotopy curves. Finally, three examples to demonstrate the advantage and efficiency of HNWTLS estimator are given and some conclusions are drawn.

To improve robust estimation performance of fully correlated nonlinear error-in-variables model, three median robust estimate methods are discussed on base of Nonlinear Weighted Total Least Squares (NWTLS), namely, median parameter method, median parameter initial value method and median variance method. After the discussion of the median robust estimation theory and the derivation of the calculation formula of the three median robust estimation methods, three iterative algorithms are developed. Through two nonlinear regression examples, four schemes including no artificial outliers, different location of outliers, different degrees of correlation, and different ratios of outliers are adopted, which proves the feasibility and effectiveness of the proposed algorithm. The experimental results show that from the statistical point of view, although the three median methods have different antioutlier effects for different nonlinear models, they are more effective than RNWTLS and NWTLS; the robust estimation results of three median methods are related to the functional model.

Based on multi‐model large‐ensemble experiments provided by Polar Amplification Model Intercomparison Project (PAMIP), we investigate the influence of the projected sea ice loss in Barents‐Kara Seas (BKS) and Sea of Okhotsk (SOK) on the Arctic stratospheric polar vortex (SPV). Results show that future BKS sea ice reduction leads to a weakened SPV during November‐February by enhancing the upward‐propagating planetary wave 1, which is more pronounced during Quasi‐Biennial Oscillation (QBO) easterly than westerly phase. Through weakening the upward‐propagating planetary wave 2, future SOK sea ice reduction is favorable for a strengthened SPV during January‐April. Inter‐model spread in the magnitudes of SPV responses to BKS sea ice reduction can be largely explained by the divergent planetary wave responses, but less so for SOK sea ice reduction. Results from a linearized baroclinic model further validate the importance of the planetary‐scale wave responses in explaining the differing SPV responses to sea‐ice loss over the two regions. Arctic sea ice reduction influences the Northern Hemispheric weather and climate through modulating Arctic stratospheric polar vortex, which is a band of strong westerly encircling the pole during winter at ∼15–40 km above the Earth's surface. However, sea ice reduction over different regions could lead to different effects on the polar vortex. Here, we compare the effects of future sea ice reduction over the Barents‐Kara Seas, in the far‐north Atlantic Ocean, and the Sea of Okhotsk, in the northwest Pacific Ocean. We use carefully designed numerical simulations to estimate the effects of sea ice reduction, separately in the above‐mentioned two regions, on the polar vortex. Sea ice reduction over the Barents‐Kara Seas weakens the polar vortex, whereas sea ice reduction over Sea of Okhotsk strengthens the polar vortex. These contrasting effects are explained by opposing changes in wave activity entering the stratosphere from below. Barents‐Kara sea ice reduction leads to the strengthened upward propagating planetary waves, which break in the stratosphere and slow the polar vortex. Conversely, Okhotsk sea ice loss reduces upward waves and strengthens the polar vortex. Barents‐Kara and Sea of Okhotsk sea ice loss weakens and strengthens polar vortex, respectively, with attendant changes in SSW frequencyPlanetary wave responses to Barents‐Kara and Okhotsk sea ice loss interfere constructively and destructively with mean flow, respectivelyPolar vortex weakening induced by Barents‐Kara sea ice loss is greater during easterly than westerly Quasi‐Biennial Oscillation phase Barents‐Kara and Sea of Okhotsk sea ice loss weakens and strengthens polar vortex, respectively, with attendant changes in SSW frequency Planetary wave responses to Barents‐Kara and Okhotsk sea ice loss interfere constructively and destructively with mean flow, respectively Polar vortex weakening induced by Barents‐Kara sea ice loss is greater during easterly than westerly Quasi‐Biennial Oscillation phase

Pyroptosis is a form of cell death triggered by the innate immune system that has been implicated in the pathogenesis of sepsis and acute lung injury. At the cellular level, pyroptosis is characterized by cell swelling, membrane rupture, and release of inflammatory cytokines, such as IL-1β. However, the role of endogenous lipids in pyroptosis remains underappreciated. We discovered that 4-hydroxynonenal (HNE), a major endogenous product of lipid peroxidation, inhibited pyroptosis and inflammasome activation. HNE at physiological concentrations (3 µM) blocked nigericin and ATP-induced cell death, as well as secretion of IL-1β, by mouse primary macrophages and human peripheral blood mononuclear cells. Treatment with HNE, or an increase of endogenous HNE by inhibiting glutathione peroxidase 4, reduced inflammasome activation in mouse models of acute lung injury and sepsis. Mechanistically, HNE inhibited the NLRP3 inflammasome activation independently of Nrf2 and NF-κB signaling, and had no effect on the NLRC4 or AIM2 inflammasome. Furthermore, HNE directly bound to NLRP3 and inhibited its interaction with NEK7. Our findings identify HNE as a novel, endogenous inhibitor of the NLRP3 inflammasome.

Phenolamide (PA) metabolites play important roles in the interaction between plants and pathogens. The putrescine hydroxycinnamoyl transferase genes OsPHT3and OsPHT4positively regulate rice cell death and resistance to Magnaporthe oryzae. The bZIP transcription factor APIP5, a negative regulator of cell death and rice immunity, directly binds to the OsPHT4promoter to regulate putrescine-derived PAs. Whether other hydroxycinnamoyl transferase (HT) genes also participate in APIP5-mediated immunity remains unclear. Surprisingly, we find that genes encoding agmatine hydroxycinnamoyl transferases OsAHT1 and OsAHT2, tryptamine hydroxycinnamoyl transferases OsTBT1 and OsTBT2, and tyramine hydroxycinnamoyl transferases OsTHT1 and OsTHT2, responsible for the biosynthesis of polyamine-derived PAs are all up-regulated in APIP5-RNAi transgenic plants compared with segregated wild-type rice. Furthermore, both OsAHT1/2and OsTBT1/2are induced during M. oryzaeinfection, showing expression patterns similar to those previously reported for OsTHT1/2and OsPHT3/4. Transgenic plants overexpressing either OsAHT2-GFPor OsTBT1-GFPshow enhanced resistance against M. oryzaeand accumulated more PA metabolites and lignin compared with wild-type plants. Interestingly, as demonstrated for OsPHT4, APIP5 directly binds to the promoters of OsAHT1/2, OsTBT1/2, and OsTHT1/2, repressing their transcription. Together, these results indicate that the HT genes are common targets of APIP5 and that PAs play critical roles in rice immunity.

As a kind of photodetector, position-sensitive-detectors (PSDs) have been widely used in noncontact photoelectric positioning and measurement. However, fabrications and applications of solar-blind PSDs remain yet to be harnessed. Herein, we demonstrate a solar-blind PSD developed from a graphene/Ga2O3Schottky junction with a 25-nanometer-thick Ga2O3film, in which the absorption of the nanometer-thick Ga2O3is enhanced by multibeam interference. The graphene/Ga2O3junction exhibits a responsivity of 48.5 mA/W and a rise/decay time of 0.8/99.8 μs at zero bias. Moreover, the position of the solar-blind spot can be determined by the output signals of the PSD. Using the device as a sensor of noncontact test systems, we demonstrate its application in measurement of angular, displacement, and light trajectory. In addition, the position-sensitive outputs have been used to demodulate optical signals into electrical signals. The results may prospect the application of solar-blind PSDs in measurement, tracking, communication, and so on.

Delivering real-time video over 3G cellular networks is an important component of mobile multimedia applications. Since hybrid coded video is very vulnerable to channel disturbances, the unavoidable burst frame losses when transmitting video over cellular network will cause severe quality degradation. It has been found that feedback channel combined multiframe is an effective tool to enhance error resilience for the wireless video communication. However, this method is affected by the long time delay of the feedback message greatly. In this paper, a novel error resilient video coding scheme for the uplink video applications over cellular networks is proposed. Unlike existing schemes, the proposed scheme adopts a radio link layer agent at the sender to implement the cross-layer feedback: get the frame losses information (by prediction or active time-out frame discarding) and send it to the application (APP) layer to adapt the encoder well to the varying channels. Experiments results show that the proposed scheme can improve both the coding efficiency and the error resilience of the uplink cellular video communication significantly. Index Terms--Cross-layer feedback, cellular network, error resilience, reference pictures selection.

Snowpacks are natural water reservoirs providing a considerable amount of water for humans and ecosystems. However, current global snow products (e.g., ESA GlobSnow v3.0), lack high spatial resolution and regional calibrations necessary to capture the high heterogeneity of snow water equivalents (SWEs) in complex Asian mountainous terrains. Therefore, our understanding of snow drought characteristics in China remains limited. Herein, we used an improved SWE product calibrated specifically for China to explore the characteristics of snow droughts, delineated by a standardized SWE index (SWEI) between 1993 and 2019. Our analysis was focused over three main snow‐covered regions of China: Qinghai–Tibet Plateau (QTP), northern Xinjiang, Northeast China. Especially during the period from 1993 to 2010, we found that the SWEI increased significantly at rates of 0.022/yr (Northeast China), 0.017/yr (northern Xinjiang), and 0.011/yr (QTP) (p< 0.01, Mann‐Kendall trend test). Increased SWEI contributed to decreasing snow drought events across China, with an obvious short‐term characteristic, whilst area proportion of the identified 1‐month snow droughts was above 46.5% across three regions. Furthermore, we found that the occurrence of snow droughts was likely mediated by large‐scale atmospheric circulation, since increased water vapor transport caused a significant vapor flux convergence in cold seasons over three regions, especially in northern Xinjiang and Northeast China. Snow droughts are caused by snow water equivalent (SWE) deficits and pose a significant climatic risk to humans and natural systems, particularly in snow‐dependent watersheds. Hence, understanding their main characteristics and driving forces is crucial for diagnosing and predicting potential climate risks. However, current research is not clear in terms of the occurrence and characteristics of snow drought in China. Therefore, we aim to investigate snow droughts based on specially calibrated SWE data in China. Alongside the increase of SWE in the three main snow‐covered areas across China, we found that the intensity of snow drought in China showed a clear downward trend, whilst both the extent and number of snow droughts decreased rapidly. Overall, these changes were likely regulated by atmospheric circulation, with the southward water vapor flux clearly increasing, providing a reliable source of water vapor and promoting the increase of snowfall. Our findings provide an important basis for the management and regulation of spring water resources to snow droughts in snow‐dependent watersheds. A reliable snow water equivalent product calibrated specifically for China was used to assess snow droughtsBetween 1993 and 2019, the occurrence of snow droughts decreased rapidly, alongside their intensity and extentThe occurrence of snow droughts was regulated by large‐scale water vapor transport A reliable snow water equivalent product calibrated specifically for China was used to assess snow droughts Between 1993 and 2019, the occurrence of snow droughts decreased rapidly, alongside their intensity and extent The occurrence of snow droughts was regulated by large‐scale water vapor transport

The acoustic response characteristics of shales were investigated by the acoustic transmission experiment, which is the basis of solving geological and engineering problems using the seismic or logging information during the process of the exploration and development of shale gas reservoirs. Based on the theory of acoustic wave and the background of acoustic transmission experiment, the initial condition, vibration source condition, boundary condition and stability condition were constructed, and the numerical simulation of acoustic transmission experiment of shales were completed through Matlab programming. The results show that under the same bedding angle, the acoustic time and attenuation coefficient of shales shown positive correlation with the bedding density; whereas under the same bedding density, the variation laws of the acoustic time and the attenuation coefficient of shales were more complex with the change of the bedding angle, that is, the acoustic time and attenuation coefficient of shales increased first, then decreased and then increased again with the increase of the bedding angle.

Trichinellosis is one of most neglected foodborne zoonoses worldwide. During Trichinella spiralisinfection, the intestinal immune response is the first line of defense and plays a vital role in the host’s resistance.

Photomemories offer great opportunities for multifunctional integration of optical sensing, data storage, and processing into one single device. However, little attention has been paid to photomemories working in the solar-blind region so far, which may have unique advantages of insusceptibility to ambient light and higher capacity. Herein, we propose and demonstrate a Ga2O3based solar-blind photomemory array with logic, arithmetic, and optoelectronic memory functions. The device shows n-type field effect-transistor performance with an on/off ratio as high as 106, a responsivity of 8 × 103A W−1, and a detectivity of 1.42 × 1014Jones, all of which are amongst the best values ever reported for Ga2O3based photodetectors. Based on the trapping and de-trapping process of holes in Ga2O3, multilevel data storage can be realized from the device. Simultaneously, the optical and electrical mixed basic logic of reconfigurable “AND” and “OR” operations have been realized in a single cell through the co-regulation of solar-blind light and the grid voltage. In addition, the photomemory can perform counting and addition operations, and the photomemory array can be utilized to realize solar-blind image storage. The results suggest that Ga2O3may have potential applications in high-performance information storage, computing, and communications.

Separating emulsified oil–water emulsions is still a significant challenge owing to the serious fouling and low permeation flux of the membrane. Here, a flexible mesoporous TiO2-SiO2composite membrane with revivability and superwettability was prepared via a sol electrospinning followed by calcination. The resulting membrane features abundant hydroxyl groups on the nanofibers, which can serve as the hydrogen bond acceptors to bind water molecules, forming a water cushion for oil repellence. It is capable of efficiently separating oil-in-water emulsion with a very high permeation flux of 3159 Lm–2h–1and a high separation efficiency of 99.94%. More importantly, the fouled membrane can be totally reclaimed with its original superwettability and separation performance by high-temperature treatment within five cycles. We believe that the provided strategy on tackling membrane fouling is highly effective, presenting a promising perspective in sustainable oil–water separation.

Vacancy-ordered double perovskites, having a great application in optoelectronic and thermoelectric devices, are variants of metal-halide perovskites. The PBE and HSE06 functionals for the first-principles calculation were used to investigate the electronic structures, optical properties, possible intrinsic defects, and formation energies of the vacancy-ordered double perovskites Cs2PdBrxCl6–x(x= 1, 2, 3, ..., 6). All the compounds had a direct band gap, and the band gap increased from 1.566 eV for Cs2PdBr6to 2.675 eV for Cs2PdCl6when Br atoms are replaced with Cl atoms. The absorption of these compounds blue-shifted with increasing Cl:Br ratio, and higher absorption coefficients can thus be acquired in the ultraviolet region. The defect calculations showed that the formation energies of VCs, VPd, and CsPdwere low, and the Fermi level was pinned near the valence band maximum. The results indicate that vacancy-ordered double perovskites are ideal candidates for lead-free solar cells with high conversion efficiencies.

Using potential vorticity to define Northern Hemisphere (NH) stratospheric polar vortex strength and position, the influence of the QBO on the polar vortex in winter is analyzed. The results show that the weakened/enhanced NH polar vortex in the lower stratosphere during easterly/westerly QBO (E/WQBO) phases is more noticeable in January and February than in November and December. Furthermore, the NH polar vortex shows a shift toward the Eurasian continent and away from North America in winter during EQBO phases compared with that during WQBO phases, with a greater shift in January and February than in November and December. The weaker QBO impact on the zonal mean zonal wind and temperature in February found in previous studies may be related to the cancelling effects of opposite‐signed anomalies over Eurasia and North America induced by the polar vortex shift associated with the QBO. During EQBO phases the upper stratospheric easterly anomalies in early winter increase the frequency of negative refractive index in the middle and high latitudes in late winter. Less planetary wave 1 propagates upward into the upper stratosphere and more wave 1 accumulates in the lower stratosphere, leading to the weakening and shift of the polar vortex in late winter. In addition, the poleward displacement of the subtropical jet during EQBO phases causes more poleward propagation of synoptic‐scale waves in the lower stratosphere, and thus more Rossby wave breaking events over Eurasia in late winter than during WQBO phases, further weakening and shifting the polar vortex in EQBO phases. Arctic stratospheric polar vortex shows a shift toward Eurasian and away from North America in winter during EQBO phasesA stronger weakening and shift of Arctic stratospheric polar vortex during EQBO phases is found in late winter than in early winterWeaker QBO impact on the zonal mean of zonal wind in February is related to the cancelling effects induced by the polar vortex shift

Background: Ubiquitination is essential for many cellular processes in eukaryotes, including 26S proteasome-dependent protein degradation, cell cycle progression, transcriptional regulation, and signal transduction. Although numerous ubiquitinated proteins have been empirically identified, their cognate ubiquitin E3 ligases remain largely unknown. Results: Here, we generate a complete ubiquitin E3 ligase-encoding open reading frames (UbE3-ORFeome) library containing 98.94% of the 1515 E3 ligase genes in the rice (Oryza sativaL.) genome. In the test screens with four known ubiquitinated proteins, we identify both known and new E3s. The interaction and degradation between several E3s and their substrates are confirmed in vitro and in vivo. In addition, we identify the F-box E3 ligase OsFBK16 as a hub-interacting protein of the phenylalanine ammonia lyase family OsPAL1–OsPAL7. We demonstrate that OsFBK16 promotes the degradation of OsPAL1, OsPAL5, and OsPAL6. Remarkably, we find that overexpression of OsPAL1or OsPAL6as well as loss-of-function of OsFBK16in rice displayed enhanced blast resistance, indicating that OsFBK16 degrades OsPALs to negatively regulate rice immunity. Conclusions: The rice UbE3-ORFeome is the first complete E3 ligase library in plants and represents a powerful proteomic resource for rapid identification of the cognate E3 ligases of ubiquitinated proteins and establishment of functional E3–substrate interactome in plants.

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Introduction:PDE5 plays a critical role in vascular smooth muscle cell (SMC) contraction by hydrolyzing 3’,5’ cyclic monophosphate (cGMP) and antagonizing cGMP-dependent protein kinase I (PKGI)-mediated vascular relaxation. SMC contractile dysfunction is implicated in the pathogenesis of aortic aneurysm (AA). PDE5 inhibitors, such as Sildenafil, have been used clinically for treating erectile dysfunction (Viagra) and pulmonary hypertension (Revatio), through promoting SMC relaxation via elevating cGMP. However, it has been reported that PDE5 expression is reduced in human thoracic aneurysms and Viagra usage is associated with human aneurysm rupture or aortic dissection in several case reports.Objective:We aim to investigate the effect of sildenafil in the development of experimental abdominal aortic aneurysm (AAA), the most common form of AA that mainly occurs in elderly male.Methods and Results:AAA was induced in C57BL/6J mouse by periaortic elastase in combination with 3-aminopropionitrile fumarate salt (BAPN) treatment to block elastin/collagen formation. Immunofluorescent staining showed decreased PDE5 expression in mouse AAA. The effect of Sildenafil was examined on pre-existing moderate AAA by providing in drinking water for 28 days. We found that Sildenafil significantly aggravated aneurysmal wall dilation and elastin degradation. Mechanistically, the effect of Sildenafil on the signaling of SMC contraction and PKGI activation were examined in the medial lesion area of AAA. Immunofluorescent staining revealed that Sildenafil significantly decreased the phosphorylation of myosin light chain 2 (MLC2) at Ser19 in AAA, a biochemical marker of SMC contraction. Proximity ligation assay (PLA) revealed an increase of cGMP-PKGI interaction by Sildenafil, an indication of PKGI activation.Conclusions:Chronic Sildenafil treatment aggravated experimental AAA development and elastin degradation by dysregulating contractile signaling in SMCs. Our findings may raise caution of clinical usage of Viagra in aneurysmal patients.

A low-polydispersity (Mw/Mn= 1.009) hyperbranched poly(phenylene sulfide) (HPPS) is successfully synthesized by modified polycondensation of an AB2monomer with a core molecule, and served as the skeleton for synthesis and stabilization of Pd nanoparticle. The effect of different PdCl2:HPPS mass ratios on the formation and stabilization of Pd nanoparticles is discussed. The resulting Pd nanoparticles with small average particle size (2.0 nm) have a narrow distribution (σ = 0.4 nm) and exhibit outstanding thermostability. These results clearly demonstrate HPPS (with uniform molecular weight) as a promising stabilizer for the synthesis of Pd nanoparticles.

Cheap and readily available commercial cellulose membranes were studied for oil–water separation and were found to have excellent performance, which could be significantly improved after treatment with chlorosulfonic acid. Two kinds of cellulose membranes, cotton and mixed cellulose ester (MCE), were used to treat the oil–water mixture and emulsions, respectively. The mechanism of this enhancement was studied in depth, and the model of the flux of membranes has been established. It was considered that the flux was strictly positively correlated to wettability, and wettability was an important driving force for fluids to flow through the membrane. This study is used for designing new membranes with both high flux and high separation efficiency, explaining the flux change of wetting membranes, and evaluating their wettability, which is of great significance in the field of oil–water separation or other fields.

The requirement for the steering wheel of a vehicle is to have a certain sense of vibration, because the intense sense of vibration will make driver fatigue. Therefore, it is very necessary to study the vibration isolation of the steering wheel. Aiming at the problem of the vibration of the a certain type of tractor's steering wheel, theoretical and experimental studies have been made, the experiment use vibration isolation pad made of Metal Rubber material, the results show that the vibration amplitude is obviously reduced. This paper proposes a novel thought to solve the vibration isolation of the system under sinusoidal and random excitation.