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This paper investigates the optimal tracking performance (OTP) of multiple-input multiple-output discrete-time communication-constrained systems by thinking about Denial of Service (DoS) attacks, codecs and additive Gaussian white noise under energy constraints. The non-cooperative relationship between DoS attacks and intrusion detection systems (IDS) is analyzed using repeated game theory. A penalty mechanism is constructed to force the attackers to adopt a cooperative strategy, thus improving the system performance. Partial factorization and spectrum decomposition are used to provide the OTP for systems. The results demonstrate that the systems' OTP are linked to intrinsic characteristics like non-minimum phase zeros and unstable poles. Finally, concrete examples are shown that the results are accurate. • The optimal tracking performance of discrete-time communication-constrained systems. • The communication factors of DoS attacks, codecs and AWGN under energy constraints. • The channel input power of the systems is considered in the performance index. • The optimal tracking performance attained by using co-prime factorization technique. [ABSTRACT FROM AUTHOR]

• The premature perforation and leakage of HAl77-2 alloy tubes in the largest LT-MED plant in China was investigated. • Corrosion behavior of alloy tubes exhibits interesting feature that corrosion pits concentrate in one strip on the top of the tube. • Root reason of failed tubes was serious pitting corrosion and stress cracking caused by the high fluid pressure and polluted seawater. • Corrosion mechanism of alloy tubes in simultaneous presence of Cl−, Fe2+/Fe3+, sulfide and NH 4 + was clearly elucidated. Premature perforation and leakage of HAl77-2 alloy heat exchanger tubes occurs after 2.5 years of service in the largest low temperature multi-effect distillation (LT-MED) plant in China. The root reasons of perforation and leakage of tubes were investigated through macroscopic morphology, chemical composition, metallographic structure, seawater quality, flowing simulation and microstructure characterization. The results show that the HAl77-2 alloy tubes with perforation leakage meet the standard requirements. And the failure of the tubes was mainly attributed to the synergistic effect of serious pitting corrosion and stress cracking caused by the high fluid pressure and polluted seawater with Fe2+/Fe3+, sulfide and NH 4 +. Especially, the velocity and pressure spatial distribution of liquid film on the outside of horizontal tubes well verified the interesting observation that corrosion pits concentrating in one strip on the top of the tube. Moreover, corrosion mechanism was proposed that the loose corrosion products of Cu 2 S, FeS and Cu 2 (OH) 3 Cl lead to the formation of some defect points on the homogeneous protective Cu 2 O layer. For these defect points, the direct expose of the alloy matrix to corrosive substances such as Cl− and NH 4 +, significantly accelerates the dissolution of Cu in form of CuCl 2 − and Cu(NH 3)2+ from the alloy. Finally, the tube occurs pitting corrosion and even perforates under the strong hydraulic erosion after long-terms of operation. [ABSTRACT FROM AUTHOR]

Biogas is a promising renewable biofuel, but hydrogen sulfide (H 2 S) and siloxanes are major obstacles in the conversion of bioenergy from biogas because they damage biogas-processing equipment. This study evaluated two biogas-purification systems for a simultaneous efficient removal of H 2 S and decamethylcyclopentasiloxane (D5), and compared their economic performance. An acidic biotrickling filter (BTF) was operated continuously for 90 days to investigate its performance under different H 2 S and D5 concentrations. Meanwhile, commercial iron-oxide-based adsorbents (IOBAs) and activated carbon (AC) were used in adsorption filters for H 2 S and D5, respectively. The results show that in terms of the ratio of D5 and H 2 S concentration (R D5:H2S) and pH of the recycling liquid, which are crucial BTF operating parameters, high elimination for both H 2 S (1.86 kg/(m3·d)) and D5 (0.282 kg/(m3·d)) was achieved at R D5:H2S of 3.7:16 and pH of 0.86. Economic analysis confirmed that BTF-AC was more profitable than IOBA-AC adsorption over a life span of 10 years because the pre-removal of D5 by a BTF significantly decreased the costs of IOBAs and AC, despite BTFs requiring a higher initial capital investment. In terms of the economic benefit of biogas production of 1200 Nm3/h, the competitive annual cost of 90.5 k$/year indicated that BTF was more profitable, yielding both cost saving and the benefit of providing heat. The advantage of BTF-AC adsorption was a more radical D5-abatament, enabling profit by selling the electricity produced from biogas to the grid. • Economic performance of two biogas purification systems was investigated. • The ratio of D5 and H 2 S concentration and pH are two crucial parameters of acidic BTF. • BTF & AC system is more profitable than iron-oxide-based adsorbent & AC adsorption. • Annual cost of acidic BTF was competitive 90.5 K$/year. [ABSTRACT FROM AUTHOR]

• The research investigates the effect of green bond issuance on stock price crash risk with the data of chinese listed companies from 2014 to 2021. • The study reveals that green bond issuance can significantly decrease stock price crash risk by addressing information asymmetry and alleviating financing constraints. • The reduction effect of green bond issuance is more pronounced among firms in polluting industries and firms under non-SOEs ownership types. • The findings provide valuable insights for policymakers and financial institutions in promoting standardization of green information disclosure and preventing stock market risk. This paper investigates the impact of green bond issuance on stock price crash risk and the mediating roles of information asymmetry and financing constraints by utilizing data of Chinese listed firms from 2014 to 2021. It is empirically tested that green bond issuance can significantly reduce stock price crash risk based on difference-in-differences (DID) methods. Our mechanism analysis shows that green bond issuance decreases stock price crash risk by addressing information asymmetry and alleviating financing constraints. Moreover, the reduction effect is more pronounced among firms in polluting industries and firms with non-SOEs ownership types. This paper provides a new perspective on stock market risk prevention. [ABSTRACT FROM AUTHOR]

Abstract In Parkinson's disease (PD), iron accumulation in the substantia nigra (SN) exacerbates oxidative stress and α-synuclein aggregation, leading to neuronal death. However, the influence of iron-related nigral degeneration on the subcortical function and global network configuration in PD remains unknown. Ninety PD patients and 38 normal controls underwent clinical assessments and multimodality magnetic resonance imaging scans. Iron accumulation in the inferior SN and disrupted functional connectivity between the bilateral striatums were observed in PD, and negative correlation between them was found in the whole population. The binarized functional network exhibited enhanced global efficiency and reduced local efficiency while the weighted functional network exhibited reduction in both, and both changes were correlated with nigral iron accumulation in PD. Mediation analysis demonstrated that the functional connectivity between bilateral striatums was a mediator between the nigral iron accumulation and weighted functional network alterations. In conclusion, our findings reveal that iron-related nigral degeneration possibly influences the functional topology mediated by striatal dysfunction, which extends the scientific understanding of PD pathogenesis. Graphical abstract Highlights • Iron accumulation in the inferior substantia nigra may characterize PD. • Nigral iron accumulation is related to striatal function and functional topology. • A potential pathway driven by iron-related nigral degeneration is suggested. • Striatal dysfunction possibly plays a mediator role in this hypothesized pathway. [ABSTRACT FROM AUTHOR]

Santanghu Coalfield, located in the northeast of Xinjiang, is an important coal base in China. In the geological prospecting stage, we found that the contents of arsenic were high at some drilling cores in Hanshuiquan district, Santanghu Coalfield, with the maximum content reaching 190 μg/g. Therefore, the research of enrichment processes and origins of arsenic is imminent. In this work, twenty-two coal samples from Xishanyao Formation were collected and tested with X-ray Diffraction (XRD) analysis, coal petrography and quality analysis, and sporopollen analysis. Furthermore, the quantitative research on occurrence modes of arsenic was operated by sequential chemical extraction experiment (SCEE) on seven samples with relatively high arsenic content from No. 9 coal seam in the middle part of Xishanyao Formation. According to the result, most of the samples from No. 9 coal seam possess high arsenic content. The contents of arsenic in all occurrence modes were ranked from high to low as follows: sulfide bound arsenic, residual form arsenic, organic bound arsenic, adsorption arsenic. For the isomorphism or solid solution form, arsenic mostly exist in crack filling pyrite of coal, contrarily, only a little occurs in clay minerals and organic matters. The further analysis show that there are three geologic origins that lead to the arsenic enrichment of coal, including the tectonic fracture-hydrothermal solution activities, the regional distribution of chemical elements and source of terrigenous detrital material, and the type of coal-forming plants. Among them, tectonic fracture-hydrothermal solution activities is the main source of arsenic in study area, which results in the sulfide bound arsenic occupying the largest proportion of total arsenic. There is a close relationship between the extraction methods and washing methods of arsenic in different occurrence modes. Therefore, this research plays a positive guiding role in the washing and utilization of high‑arsenic coal. We will further study the washing properties of high arsenic coals to improve the utility value of high arsenic coal in future investigation. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) with coral-like nanostructure was prepared via chemical oxidative polymerization in the presence of sunset yellow (SY) as dopant and surfactant. The results showed that in comparison with the microsized bulky structure of PANI undoped with SY, the coral-like nanostructure of PANI doped with SY (PANI/SY) was observed and the diameter of coral branch decreased from 180 nm to 100 nm with the increase of feeding molar ratio of SY to aniline. Coral-like PANI/SY showed the large specific capacitance of 467 F/g and nice electrochemical stability when the feeding molar ratio of SY to aniline was 0.035:1, owning to its special coral-like nanostructure and high conductivity of 15.0 S/cm, which was essentially attributed to the synergistic effects of high doping level, ordered arrangement of PANI chain and strong π–π interaction between PANI and SY. [ABSTRACT FROM AUTHOR]

High-solids anaerobic digestion of sewage sludge is a promising technology, but blocked mass transfer is a key problem. However, the blockage process is difficult to quantify due to lack of direct evidence and data. In this study, a modified diffusion membrane cell was used to analyze the diffusion coefficients in high-solids sludge using iodide ions as a soluble tracer. The total solids (TS) concentration was verified to have a significant influence on the mass transfer in the sludge. The diffusion coefficients decreased sharply due to the decrease in free water when sludge TS concentration increased from 6% to 12%; the coefficients then decreased gradually, mainly by capillary diffusion, to a lower value when sludge TS increased further to 15%. Compared with the diffusion coefficient in water, the value in the diluted dewatered sludge at TS 14.92% decreased almost eightfold, while the value in the digested sludge at TS 15.21% decreased over 90 times. Furthermore, the diffusion coefficients in the digested sludge were an order of magnitude lower than in the diluted dewatered sludge at the same water content, because the digested sludge had smaller sized particles and less free water. [ABSTRACT FROM AUTHOR]

Hydrophobic organic pollutants (HOCs) in the complex groundwater and soil pose serious technical challenges for sustainable remediation. Herein, an asymmetric membrane (PCAM), inspired by the plant cuticle, was comprised of a top polydimethylsiloxane layer being selectively penetrable to HOCs from complex solution with humic acid, followed by transfer and catalyst layers with biochar pyrolyzed by 300 °C (BC300) and 700 °C (BC700). The PCAM triggered the advanced oxidation of the coming pollutant. The graphitized biochar layer of the PCAM acted as catalysts that induced HOC removal through a non-radical oxidation pathway. Compared to one type biochar membrane, the sequential multi-biochar composite membrane had a faster removal efficiency. The greater uptake and transport performance of multi-biochar composite membrane could be due to the larger pore size and distribution properties of PCAM physicochemical properties and oxidative degradation of peroxymonosulfate. The developed PCAM technology benefits from selective adsorption and catalytic oxidation and has the potential to be applied in complex environmental restoration. [Display omitted] • A selective layer of PCAM was permeable to organics rather than humic acid and water. • A transfer layer of PCAM supported the selective layer and quickly adsorbed HOC. • A catalytic layer of PCAM was beneficial to a high mass transfer flux and activated oxidant. • The PCAM and oxidation degradation favor superior removal of HOCs in complex system. [ABSTRACT FROM AUTHOR]

• Providing new knowledge relating to the bioassay of compounds exhibiting high biomatrix interference and poor CID efficiency. • Developed an LC-DMS-MS/MS with MIM based assay to determine polycyclic triterpenoids in rat plasma using low sample volume. • DMS provides a new separation dimension which significantly decreases interference and increases selectivity. • A non-derivatization sample preparation step while ensuring high selectivity and low quantitation limit. [Display omitted] Ursolic acid (UA) is a naturally occurring pentacyclic triterpene widely distributed in fruits and plants. It is pharmacologically active and has the potential to be a useful therapeutic compound. To date, bioanalysis of UA has been limited by biomatrix interference and poor collision induced dissociation (CID) efficiency in tandem mass spectrometry. In this study, we developed a method based on liquid chromatography differential mobility spectrometry tandem mass spectrometry LC-DMS-MS/MS with multiple ion monitoring (MIM) for quantitation of UA in rat plasma. The method involves efficient sample preparation by solid phase extraction and requires only a limited volume of plasma (40 μL) to achieve linearity in the 1–100 ng/mL range with good accuracy and precision. The method was successfully applied to a pharmacokinetic study of orally administered UA in rat. The results indicate that LC-DMS-MS/MS with MIM is a useful strategy for the bioassay of UA suitable for high throughput analysis. [ABSTRACT FROM AUTHOR]

A hallmark of type 2 diabetes (T2D) is hepatic resistance to insulin's glucose-lowering effects. The serum- and glucocorticoid-regulated family of protein kinases (SGK) is activated downstream of mechanistic target of rapamycin complex 2 (mTORC2) in response to insulin in parallel to AKT. Surprisingly, despite an identical substrate recognition motif to AKT, which drives insulin sensitivity, pathological accumulation of SGK1 drives insulin resistance. Liver-specific Sgk1 -knockout (Sgk1 Lko) mice display improved glucose tolerance and insulin sensitivity and are protected from hepatic steatosis when fed a high-fat diet. Sgk1 promotes insulin resistance by inactivating AMP-activated protein kinase (AMPK) via phosphorylation on inhibitory site AMPKαSer485/491. We demonstrate that SGK1 is dominant among SGK family kinases in regulation of insulin sensitivity, as Sgk1 , Sgk2 , and Sgk3 triple-knockout mice have similar increases in hepatic insulin sensitivity. In aggregate, these data suggest that targeting hepatic SGK1 may have therapeutic potential in T2D. [Display omitted] • SGK1 drives insulin resistance in liver in response to high-fat diet consumption • SGK1 promotes insulin resistance by phosphorylating and inhibiting AMPK • Expression of AMPK that cannot be acted upon by SGK1 promotes insulin sensitivity • SGK1 is dominant among SGK family kinases regulating insulin sensitivity in liver The insulin-activated serine/threonine kinase serum- and glucocorticoid-induced kinase 1 (SGK1) phosphorylates an identical substrate recognition motif to Akt. Here, Zhou et al. show that, in contrast to Akt, HFD-induced SGK1 overactivation promotes insulin resistance in liver by phosphorylating and inhibiting the activity of AMP-activated protein kinase. [ABSTRACT FROM AUTHOR]

Plot of the reduction production of the samples vs. irradiation time for CO and Schematic diagram of the reduction mechanism through Cd 0. 2 Zn 0. 8 S@Ti 3 C 2 nanocomposites. [Display omitted] • Cd 0. 2 Zn 0. 8 S/Ti 3 C 2 nanocomposites are synthesized by three-step solvethermal method at low temperature. • Cd 0. 2 Zn 0. 8 S/Ti 3 C 2 nanocomposites display excellent photocatalytic reduction CO 2 activity. • Cd 0. 2 Zn 0. 8 S/Ti 3 C 2 nanocomposites exhibits high recycle stability. In order to achieve global energy demand by sustainable energy development and grappling climate change, the ultimate plan is the reduction and conversion of carbon dioxide (CO 2). However, in the field of photocatalytic reduction CO 2 , developing stable, low-cost, and efficient catalyst is still a significant challenge. A series of Cd 0. 2 Zn 0. 8 S@Ti 3 C 2 nanocomposites with different Ti 3 C 2 loading contents are prepared by three-step solvothermal method. Photocatalytic efficiencies of different Cd 0.2 Zn 0.8 S@Ti 3 C 2 nanocomposites under visible-light irradiation show that Cd 0.2 Zn 0.8 S@Ti 3 C 2 nanocomposite with 5 wt% of Ti 3 C 2 exhibits significant improvement in the photocatalytic performance of CO 2 reduction, which shows significant CO (3.31 μmol h−1 g−1) and CH 4 (3.51 μmol h−1 g−1) production rates. Such a considerable increase in the photocatalytic efficiency is due to an efficient electron-hole separation and transfer at the interface between Cd 0. 2 Zn 0. 8 S and Ti 3 C 2 , which is confirmed by photoluminescence (PL) and electrochemical impedance spectroscopy (EIS). In addition, Cd 0.2 Zn 0.8 S@Ti 3 C 2 nanocomposites exhibit high cycling stability during the CO 2 photocatalytic reduction, and the photocatalytic mechanism is also discussed. [ABSTRACT FROM AUTHOR]

Membrane hydrophilic modification is a common way to improve membrane antifouling performance. However, conventional modifications based on the same type of hydrophilic group/unit can boost membrane hydrophilicity only by increasing quantity of the introduced hydrophilic unites, while influences of the additive molecular architecture to surface modification were ignored. Thus, two ethyl cellulose (EC) based additives constructed with the same number of the hydrophilic methyl diethylene glycol methacrylate (MDEGMA) monomer but in different molecular architectures were purposely prepared. After blending with cellulose acetate (CA) in the same ratio to form membranes through non-solvent induced phase inversion (NIPS), the additive with less but longer hydrophilic chains (AL) endowed the membrane (ML) with higher hydrophilicity as well as better resistance to the typical organic and biological fouling than the membrane (MS) modified by the additive with more but shorter hydrophilic grafts (AS). Obviously, AL might provide higher hydrophilic modification efficiency than AS during the membrane modification. The additive molecular architecture re-construction is a more sustainable approach than increasing the hydrophilic additive quantity to improve membrane hydrophilicity. This study may guide the development of highly efficient hydrophilic additive for sustainable membrane modification, which indicated a route to widen the application of membrane and lower the cost. Image 1 • Additives with the same number of hydrophilic monomers but in different designer molecular architectures were synthesized. • The long and sparse grafts was more efficient than the short and dense chains in membrane hydrophilic modification. • Excellent fouling resistance was achieved by the hydrophilic membrane. • Molecular design and re-construction indicates an efficient route to antifouling membrane preparation. [ABSTRACT FROM AUTHOR]

The performance of object detection networks is often limited by the depth of the feature extraction network. Increasing network parameters may yield limited improvements in the detection system's performance. Additional careful designs of network details are necessary, but they can significantly increase training difficulty. This paper introduces a novel object detection method that utilizes generative adversarial training. Our approach focuses on minimizing the EM distance (Wasserstein distance) of the feature distribution as the primary training objective. We enhance the image features so that training of GAN (Generative Adversarial Networks) yields a feature distribution that exceeds that of the original dataset, obtaining a better feature extraction network. A new loss function is also added to the adversarial training process to ensure stable improvement of the detector. A comparative experiment conducted with the original CenterNet network on MS COCO (Microsoft Common Objects in COntext) 2017 reveals that the generative adversarial training method significantly improves the average precision for most of the examined backbone networks. Among the four backbone networks employed in the experiments, the mean improvement in network AP (Average Precision) values ranged from 0.3 to 0.9, demonstrating their success with minimal training efforts. Moreover, none of the four backbone networks experienced an increase in network parameters during inference. Experimental results indicate that the proposed architecture effectively enhances the network's feature extraction capability without compromising speed during inference. [ABSTRACT FROM AUTHOR]