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BACKGROUND: Although nonfat milk has been used worldwide in the industrial dairy process, little is known about the effects of fat separation during the manufacturing process on skim milk's structural and digestive properties. This study investigated the effects of the manufacturing process on the structure and in vitro digestion properties of skim goat milk, particularly emphasizing fat separation. RESULTS: Changes in the surface charge and hydrophobicity of milk proteins caused by fat separation resulted in oxidation and aggregation in the subsequent homogenization, heat and spray‐drying processing, which affected its digestibility. Compared with separation by dish separator (DS), skim milk after tubular centrifugal separation (CS) showed a higher initial and final digestibility. The CS samples also had a lower surface hydrophobicity level and higher free sulfhydryl content, ζ‐potential, and average particle size (P < 0.05). Goat milk protein after CS was more readily oxidized and aggregated during the subsequent homogenization and heat treatment, as evidenced by the higher carbonyl content and particle size. Centrifugal separation also converted more β‐sheets to α‐helices, thus promoting the aggregation of oxidized skim milk protein. CONCLUSION: The skim milk after CS and DS demonstrated different structural and digestive properties. Skim goat milk products after CS were more susceptible to oxidant‐induced protein structural changes, resulting in higher protein digestibility. These findings provide insights into the mechanism involved in the control of gastric digestion of skim milk during manufacturing process. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

GpsB links peptidoglycan synthases to other proteins that determine the shape of the respiratory pathogen Streptococcus pneumoniae (pneumococcus; Spn) and other low‐GC Gram‐positive bacteria. GpsB is also required for phosphorylation of proteins by the essential StkP(Spn) Ser/Thr protein kinase. Here we report three classes of frequently arising chromosomal duplications (≈21–176 genes) containing murZ (MurZ‐family homolog of MurA) or murA that suppress ΔgpsB or ΔstkP. These duplications arose from three different repeated sequences and demonstrate the facility of pneumococcus to modulate gene dosage of numerous genes. Overproduction of MurZ or MurA alone or overproduction of MurZ caused by ΔkhpAB mutations suppressed ΔgpsB or ΔstkP phenotypes to varying extents. ΔgpsB and ΔstkP were also suppressed by MurZ amino‐acid changes distant from the active site, including one in commonly studied laboratory strains, and by truncation or deletion of the homolog of IreB(ReoM). Unlike in other Gram‐positive bacteria, MurZ is predominant to MurA in pneumococcal cells. However, ΔgpsB and ΔstkP were not suppressed by ΔclpCP, which did not alter MurZ or MurA amounts. These results support a model in which regulation of MurZ and MurA activity, likely by IreB(Spn), is the only essential requirement for StkP‐mediated protein phosphorylation in exponentially growing D39 pneumococcal cells. [ABSTRACT FROM AUTHOR]

Coal gangue (CG), which is mainly generated during coal excavation, mining, and coal washing, is an industrial solid waste that is recognized as an environmental pollutant. The ever‐increasing amount of CG produced is a serious threat to the ecological environment and property safety, especially in China, which is the largest coal producer and consumer in the world. Considerable studies have investigated means for utilizing CG worldwide. This review summarizes and discusses various porous inorganic materials made from CG, including cement‐based porous materials, porous bricks, porous ceramics (cordierite and mullite) and glasses, porous geopolymers, zeolites, aerogels, and porous carbon materials. Different preparation processes and performances of each type of porous inorganic materials were reviewed. Porous CG‐based materials can be used as promising adsorbents for the removal of various pollutants and have good potential for use in construction industry as well as catalyst material applications. Besides, porous materials obtained from CG have also been tested as slow‐release fertilizers after the absorption of phosphate, as electrode materials, and as oil‐in‐water separation agents. The systematic summary of porous materials based on CG aims at promoting high‐value‐added applications for this waste. Future research directions for the use of CG as a raw material are also presented. [ABSTRACT FROM AUTHOR]

High‐performance damping materials are significant toward reducing vibration and maintaining stability for industrial applications. Herein, a yolk–shell piezoelectric damping mechanism is reported, which can enhance mechanical energy dissipation and improve damping capability. With the addition of yolk–shell particles and carbon nanotube (CNT) conductive network, damping properties of various resin matrices are enhanced with the energy dissipation path of mechanical to electrical to heat energy. Particularly, the peak loss factor of epoxy composites reaches 1.91 and tan δ area increases by 25.72% at 20 °C. The results prove the general applicability of yolk–shell piezoelectric damping mechanism. Besides, the novel damping materials also exhibit excellent flexibility, stretchability, and resilience, offering a promising application toward damping coating, indicating broad scope of application in transportation and sophisticated electronics, etc. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the trajectory tracking control problem for autonomous underwater vehicles (AUVs) with time‐varying external disturbances of currents and waves in the sea. To solve the problem, a fixed‐time extended state observer (FTESO)‐based tracking controller is proposed. Firstly, by using the extended state observer, the FTESO is proposed for estimating the external disturbances and the velocities of the AUV within the fixed convergence time. Based on the FTESO, the fixed‐time controller is proposed for reducing the tracking errors and improving robustness performance. Theoretical analysis is given, which shows that the unknown external disturbances can be compensated and tracking error can converge to zero within the fixed time. Simulation results show that the proposed FTESO controller not only guarantees the fixed‐time convergence but also reduces the trajectory tracking errors of the AUV. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are emitted into the environment by daily anthropogenic activities and they potentially threaten human health. Over the past 40 years, the coupling between PAHs emissions driven by energy transition and socioeconomic factors has yet to be determined, and future trends between the two parameters are unclear. In China, the emissions of PAHs increased from 1980 to 2016, and the average annual variation rate was 3.5%. After 2016, PAHs emissions were decoupled from socioeconomic growth. PAHs emissions exhibited a change from a developed region (eastern region) to an undeveloped region (central region and western region). The emissions of PAHs, if only driven by energy transition, will reach a peak in 2035 under the shared economic pathways (SSP1, SSP2, SSP4, and SSP5), which are defined to assess sustainable development. The emissions of PAHs will continuously increase by +9.8% under SSP3 during 2020–2050. Comparing these five socioeconomic pathways, SSP1 is the possible choice to achieve the sustainable decoupling of the emissions of PAHs and socioeconomic growth by transforming the drivers of economic growth, thereby optimizing the energy system and cultivating environmentally friendly behaviors. Plain Language Summary: The widespread occurrences of polycyclic aromatic hydrocarbons (PAHs) in air, surface water, soils, sediments, and biota have been a concern because of their toxic effects on ecosystem and human health. Thus, it is imperative to alleviate emissions of PAHs to reduce human health risks. Significant knowledge gaps exist regarding whether China's PAHs emissions driven by energy transition will decline or continue to increase. In this study, we analyzed the dynamic changes in PAHs emissions from industrial coal combustion, domestic coal combustion, primary aluminum production, gasoline, diesel oil, straw burning, natural gas, and coking coal during the period 1980–2020. Then, a coupling model was employed to explore the coupling relationship between PAHs emissions and socioeconomic growth (gross domestic product and population). Finally, future PAHs emissions were predicted using five shared socioeconomic scenarios (SSP1, SSP2, SSP3, SSP4, and SSP5) during the period 2020–2050. The emissions of PAHs, if only driven by energy transition, will reach a peak in 2035 under the shared economic pathways (SSP1, SSP2, SSP4, and SSP5), which are defined to assess sustainable development. The results will provide a solid basis for policymakers to enact mitigation strategies of PAHs emissions in China. Key Points: Polycyclic aromatic hydrocarbons (PAHs) emissions exhibited a change from a developed region to an undeveloped regionThe emissions of PAHs driven by energy transition will reach a peak in 2035 under the shared economic pathwaysSSP1 is the possible choice to achieve the sustainable decoupling of the emissions of PAHs and socioeconomic growth [ABSTRACT FROM AUTHOR]

Aims/Introduction: Few people have reported whether there are sex differences in blood lipids and lipid ratios in type 2 diabetic foot (T2DF) patients in China. This study attempts to identify the contribution to sex‐specific differences in blood lipids and lipid ratios in these patients. Materials and Methods: In this case–control study, we explore 306 patients with T2DF as the study group and 306 patients with type 2 diabetes mellitus as the control group. Patients were diagnosed according to the Standards of Medical Care in Diabetes–2014 (American Diabetes Association). Blood lipid and lipid ratios were determined according to the National Cholesterol Education Program Adult Treatment Panel III criteria. Results: We studied male patients with T2DF who were aged 68.00 years (18.00 years) and females who were aged 73.50 years (19.00 years); 61.76% of the patients were men. Men had higher body mass index and glycated hemoglobin levels than women. Compared with type 2 diabetes mellitus patients, T2DF patients had significant differences in total cholesterol/high‐density lipoprotein cholesterol (HDL‐C), low‐density lipoprotein cholesterol/HDL‐C and apolipoprotein (apo)B/apoA‐I ratios. HDL‐C, triglyceride, apoA‐I and apoB/apoA‐I ratio showed cardiovascular disease risk in men, whereas total cholesterol, low‐density lipoprotein cholesterol, apoB, and the low‐density lipoprotein cholesterol/HDL‐C and total cholesterol/HDL‐C ratios were better predictors in women. The apoB/apoA‐I ratio odds ratio values were 2.18 (95% confidence interval 1.17–4.41) and 2.14 (95% confidence interval 1.14–4.00) in male patients with T2DF before and after adjusting for age, respectively (P < 0.05). Conclusions: T2DF patients present sex‐specific differences in their blood lipid and lipid ratios, especially in the apoB/apoA‐I ratio, which could be a better indicator for cardiovascular disease risk. [ABSTRACT FROM AUTHOR]

Flash pyrolysis, which combines conventional pyrolysis with flash sintering, was first conducted to produce polymer derived SiC‐TiC nanocomposites. Pre‐pyrolysis at 800℃ allows the conversion from titanium isopropoxide (TTIP) modified polysiloxane to an amorphous SiTiOC ceramic. The subsequent application of an electric field gives rise to the formation of turbostratic carbon and creates Joule heating to obtain a sample internal temperature of ~1400℃. The precipitation of β‐SiC, TiC, as well as titanium oxides is realized upon carbothermal reduction of extensively phase separated SiO2 and TiO2 with carbon. Increasing TTIP content embodies the nanocomposites with prominent electrical percolation behaviors. The electrical transport of the synthesized ceramics follows an amorphous semiconductor mechanism. High thermal stability in air is guaranteed, thanks to the in‐situ formed TiC nanocrystals and preferentially reduced amorphous carbon. Flash pyrolyzed nanocomposite with a Ti:Si molar ratio of 0.20 exhibits the highest electrical conductivity (0.696 S/cm) and minimum mass change (~2%) at 1000℃, serving as a competitive candidate for electro‐discharge machining (EDM) applications or self‐standing conducting devices that must withstand high temperature conditions. [ABSTRACT FROM AUTHOR]

This paper studies flexible line power control in the interior of meshed smart direct current (DC) distribution systems. The idea and principle of bidirectional line power control with a DC/DC converter in series are proposed first. Then the model of the line with the DC/DC converter is established from the view of power system analysis. The operation modes and control framework are analyzed in depth to adapt to the complicated power and voltage uncertainty in DC systems. The effects of the flexible line power control on the whole system are presented in detail. Finally, simulation performed in SIMULINK verifies the effectiveness of proposed flexible line power flow control technology. © 2018 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]

Suppressor mutations were isolated that obviate the requirement for essential PBP2b in peripheral elongation of peptidoglycan from the midcells of dividing Streptococcus pneumoniae D39 background cells. One suppressor was in a gene encoding a single KH-domain protein (KhpA). Δ khpA suppresses deletions in most, but not all ( mltG), genes involved in peripheral PG synthesis and in the gpsB regulatory gene. Δ khpA mutations reduce growth rate, decrease cell size, minimally affect shape and induce expression of the WalRK cell-wall stress regulon. Reciprocal co-immunoprecipitations show that KhpA forms a complex in cells with another KH-domain protein (KhpB/JAG/EloR). Δ khpA and Δ khpB mutants phenocopy each other exactly, consistent with a direct interaction. RNA-immunoprecipitation showed that KhpA/KhpB bind an overlapping set of RNAs in cells. Phosphorylation of KhpB reported previously does not affect KhpB function in the D39 progenitor background. A chromosome duplication implicated FtsA overproduction in Δ pbp2b suppression. We show that cellular FtsA concentration is negatively regulated by KhpA/B at the post-transcriptional level and that FtsA overproduction is necessary and sufficient for suppression of Δ pbp2b. However, increased FtsA only partially accounts for the phenotypes of Δ khpA mutants. Together, these results suggest that multimeric KhpA/B may function as a pleiotropic RNA chaperone controlling pneumococcal cell division. [ABSTRACT FROM AUTHOR]

GpsB regulatory protein and StkP protein kinase have been proposed as molecular switches that balance septal and peripheral (side-wall like) peptidoglycan (PG) synthesis in Streptococcus pneumoniae (pneumococcus); yet, mechanisms of this switching remain unknown. We report that Δ divIVA mutations are not epistatic to Δ gpsB division-protein mutations in progenitor D39 and related genetic backgrounds; nor is GpsB required for StkP localization or FDAA labeling at septal division rings. However, we confirm that reduction of GpsB amount leads to decreased protein phosphorylation by StkP and report that the essentiality of Δ gpsB mutations is suppressed by inactivation of PhpP protein phosphatase, which concomitantly restores protein phosphorylation levels. Δ gpsB mutations are also suppressed by other classes of mutations, including one that eliminates protein phosphorylation and may alter division. Moreover, Δ gpsB mutations are synthetically lethal with Δ pbp1a, but not Δ pbp2a or Δ pbp1b mutations, suggesting GpsB activation of PBP2a activity. Consistent with this result, co-IP experiments showed that GpsB complexes with EzrA, StkP, PBP2a, PBP2b and MreC in pneumococcal cells. Furthermore, depletion of GpsB prevents PBP2x migration to septal centers. These results support a model in which GpsB negatively regulates peripheral PG synthesis by PBP2b and positively regulates septal ring closure through its interactions with StkP-PBP2x. [ABSTRACT FROM AUTHOR]

In ellipsoid-shaped ovococcus bacteria, such as the pathogen Streptococcus pneumoniae (pneumococcus), side-wall (peripheral) peptidoglycan (PG) synthesis emanates from midcells and is catalyzed by the essential class B penicillin-binding protein PBP2b transpeptidase (TP). We report that mutations that inactivate the pneumococcal YceG-domain protein, Spd_1346 (renamed MltG), remove the requirement for PBP2b. Δ mltG mutants in unencapsulated strains accumulate inactivation mutations of class A PBP1a, which possesses TP and transglycosylase (TG) activities. The 'synthetic viable' genetic relationship between Δ pbp1a and Δ mltG mutations extends to essential Δ mreCD and Δ rodZ mutations that misregulate peripheral PG synthesis. Remarkably, the single MltG(Y488D) change suppresses the requirement for PBP2b, MreCD, RodZ and RodA. Structural modeling and comparisons, catalytic-site changes and an interspecies chimera indicate that pneumococcal MltG is the functional homologue of the recently reported MltG endo-lytic transglycosylase of Escherichia coli. Depletion of pneumococcal MltG or mltG(Y488D) increases sphericity of cells, and MltG localizes with peripheral PG synthesis proteins during division. Finally, growth of Δ pbp1a Δ mltG or mltG(Y488D) mutants depends on induction of expression of the WalRK TCS regulon of PG hydrolases. These results fit a model in which MltG releases anchored PG glycan strands synthesized by PBP1a for crosslinking by a PBP2b:RodA complex in peripheral PG synthesis. [ABSTRACT FROM AUTHOR]