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Background Purpose Methods Results Conclusions Cyclotron‐based proton therapy systems utilize the highest proton energies to achieve an ultra‐high dose rate (UHDR) for FLASH radiotherapy. The deep‐penetrating range associated with this high energy can be modulated by inserting a uniform plate of proton‐stopping material, known as a range shifter, in the beam path at the nozzle to bring the Bragg peak within the target while ensuring high proton transport efficiency for UHDR. Aluminum has been recently proposed as a range shifter material mainly due to its high compactness and its mechanical properties. A possible drawback lies in the fact that aluminum has a larger cross‐section of producing secondary neutrons compared to conventional plastic range shifters. Accordingly, an increase in secondary neutron contamination was expected during the delivery of range‐modulated FLASH proton therapy, potentially heightening neutron‐induced carcinogenic risks to the patient.We conducted neutron dosimetry using simulations and measurements to evaluate excess dose due to neutron exposure during UHDR proton irradiation with aluminum range shifters compared to plastic range shifters.Monte Carlo simulations in TOPAS were performed to investigate the secondary neutron production characteristics with aluminum range shifter during 225 MeV single‐spot proton irradiation. The computational results were validated against measurements with a pair of ionization chambers in an out‐of‐field region (≤$\le$ 30 cm) and with a Proton Recoil Scintillator‐Los Alamos rem meter in a far‐out‐of‐field region (0.5–2.5 m). The assessments were repeated with solid water slabs as a surrogate for the conventional range shifter material to evaluate the impact of aluminum on neutron yield. The results were compared with the International Electrotechnical Commission (IEC) standards to evaluate the clinical acceptance of the secondary neutron yield.For a range modulation up to 26 cm in water, the maximum simulated and measured values of out‐of‐field secondary neutron dose equivalent per therapeutic dose with aluminum range shifter were found to be (0.57±0.02)mSv/Gy$(0.57\pm 0.02)\ \text{mSv/Gy}$ and (0.46±0.04)mSv/Gy$(0.46\pm 0.04)\ \text{mSv/Gy}$, respectively, overall higher than the solid water cases (simulation: (0.332±0.003)mSv/Gy$(0.332\pm 0.003)\ \text{mSv/Gy}$; measurement: (0.33±0.03)mSv/Gy$(0.33\pm 0.03)\ \text{mSv/Gy}$). The maximum far out‐of‐field secondary neutron dose equivalent was found to be (8.8±0.5$8.8 \pm 0.5$) μSv/Gy$\umu {\rm Sv/Gy}$ and (1.62±0.02$1.62 \pm 0.02$) μSv/Gy$\umu {\rm Sv/Gy}$ for the simulations and rem meter measurements, respectively, also higher than the solid water counterparts (simulation: (3.3±0.3$3.3 \pm 0.3$) μSv/Gy$\umu {\rm Sv/Gy}$; measurement: (0.63±0.03$0.63 \pm 0.03$) μSv/Gy$\umu {\rm Sv/Gy}$).We conducted simulations and measurements of secondary neutron production under proton irradiation at FLASH energy with range shifters. We found that the secondary neutron yield increased when using aluminum range shifters compared to conventional materials while remaining well below the non‐primary radiation limit constrained by the IEC regulations. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a central nervous system disease with the highest disability and mortality rate worldwide, and it is caused by a variety of factors. The most common medications for PD have side effects with limited therapeutic outcomes. Many studies have reported that chitosan oligosaccharide (COS) crossed blood-brain barrier to achieve a neuroprotective effect in PD. However, the role of COS in PD remains unclear. The present study demonstrated that COS increased dopaminergic neurons in the substantia nigra (SN) and ameliorated dyskinesia in a PD mouse model. Moreover, COS reduced gut microbial diversity and faecal short-chain fatty acids. Valeric acid supplementation enhanced the inflammatory response in the colon and SN, and it reversed COS - suppressed dopamine neurons damage. Autophagy was involved in COS modulating inflammation through valeric acid. These results suggest that COS reduces bacterial metabolites - valeric acid, which diminishes inflammation via activating autophagy, ultimately alleviating PD. [ABSTRACT FROM AUTHOR]

This paper investigates the evolution of the soil-water characteristic curve (moisture content-suction relationships, SWCC), soil shrinkage characteristic curve (moisture content-void ratio relationships, SSCC) and microstructure of a compacted expansive clay during drying-wetting (DW) cycles and closed-system freeze-thaw (FT) cycles. Experimental results reveal that FT and DW cycles significantly change the clay's macropore system by destructing the compaction-induced macropores but have little impact on the micropore system. FT cycles induce invisible microcracks and DW cycles result in visible macrocracks, both of which (i) significantly reduced the clay's water retention capacity in the low suction range and volumetric shrinkage from saturated condition to oven-dryness, (ii) introduce structural shrinkage stage to the SSCC and (iii) have no impact on the shrinkage and plastic limits of the SSCC. The slope of the SSCC in the normal and residual shrinkage stages reduces after FT cycles due to the development of microcracks but is less affected by DW cycles. The moisture content-void ratio-suction relationships obtained from specimens with different FT and DW histories are likely distributed on a unique surface and this surface was reasonably described by a model proposed in this study using only one set of parameters. Studies in this paper are useful for advancing the understanding of the influences of environmental factors on the hydromechanical behaviour of expansive clays. • Influences of FT and DW cycles on the SWCC and SSCC are compared. • FT / DW cycles destruct soils' initial macropores and introduce micro- and macrocracks. • FT / DW cycles reduce clay's ability to retain water and to shrink. • A unique surface is proposed for moisture content-void ratio-suction relationships. [ABSTRACT FROM AUTHOR]

• An adaptive fuel cell model is developed for a polymer electrolyte fuel cell system. • Load changes and long term operation properties can be addressed by the model. • The internal parameters are relevant to the accuracy of the model. • Genetic algorithm is employed to initialize the model's internal parameters. • Internal parameters are updated rapidly. Polymer electrolyte fuel cells have been widely used in automotive applications, in which fast-response and highly accurate fuel cell systems are required to achieve good performance. To fulfill this requirement, an adaptive fuel cell model is developed herein for a polymer electrolyte fuel cell system. The model is established on the basis of a least squares support vector machine. A genetic algorithm is employed to set the initial values of the internal parameters of the model by incorporating existing data from previous experiments. Then, an adaptive process is further conducted to provide an online update of the model's internal parameters. The genetic algorithm can effectively avoid the initial parameters by falling to a local minimum. Moreover, the online updating of the parameters makes the model more adaptive to load changes in the real-time application of the fuel cell system. The proposed model is experimentally-tested on a fuel cell test rig. The results indicate that the proposed model can accurately and effectively predict fuel cell voltage. In addition, two reference models are employed to compare with the online adaptive model, by which the advantages of the genetic algorithm and parameter updating are verified. The model accuracy is improved significantly with the genetic algorithm, indicating the importance of initial parameters setting. The gradient method also benefits the model's accuracy in online modeling and predicting, but its efficiency still depends on the initial parameters. This online adaptive model can easily address frequent load change and the long term operation of fuel cells. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ionic liquid-catalyzed sludge hydrothermal achieves 6–15 % energy recovery. • More than 75% of Fe, Mn, Zn, Co, and Cd is removed by ionic liquid. • Ionic liquid promotes production of fixed carbon and small molecule polymers. • Ionic liquid leads to mesopore collapse and graphitization of hydrochar. An ionic liquid (IL, [DMAPA]HSO 4) was prepared to facilitate the removal of heavy metals by hydrothermal carbonization (HTC) in sewage sludge (SS) and to obtain a positive energy recovery (ER, (Energy output /Energy input − 1) > 0). The results found that the removal efficiencies of the Fe, Mn, Zn, Co, and Cd from SS exceeded 75 % with positive ER (6 %) at 20 wt% IL dosage (IL:SS). IL promoted the HTC reactions of proteins and polysaccharides to produce fixed carbon and small molecule polymers. The process mainly relies on IL to catalyze the dehydration and graphitization of SS and to destroy the heavy metal binding sites such as carboxyl and hydroxyl groups. Additionally, IL aids in constructing the macropore structures in hydrochar, thereby facilitating the release of heavy metals and water during the HTC process. This discovery holds promise for removing heavy metals from SS by one-pot HTC processes with positive energy recovery. [ABSTRACT FROM AUTHOR]

Owing to the global health crisis of resistant pathogenic infections, researchers are emphasizing the importance of novel prevention and control strategies. Existing antimicrobial drugs predominantly target a few pathways, and their widespread use has pervasively increased drug resistance. Therefore, it is imperative to develop new antimicrobial drugs with novel targets and chemical structures. The de novo cysteine biosynthesis pathway, one of the microbial metabolic pathways, plays a crucial role in pathogenicity and drug resistance. This pathway notably differs from that in humans, thereby representing an unexplored target for developing antimicrobial drugs. Herein, we have presented an overview of cysteine biosynthesis pathways and their roles in the pathogenicity of various microorganisms. Additionally, we have investigated the structure and function of enzymes involved in these pathways as well as have discussed drug design strategies and structure–activity relationships of the enzyme inhibitors. This review provides valuable insights for developing novel antimicrobials and offers new avenues to combat drug resistance. [Display omitted] • Cysteine biosynthesis pathway plays key role in the pathogenicity and drug resistance of pathogens. • Structures and functions of key enzymes in cysteine biosynthesis. • Drug design strategies and the structure–activity relationships of inhibitors targeting cysteine biosynthesis. [ABSTRACT FROM AUTHOR]

Our understanding of the late Eocene to early Oligocene provenance evolution of the East China Sea Shelf Basin has been limited, which hampers our study of the synergistic effects between East Asia offshore sedimentation and major rivers. To address this, we compared newly acquired detrital zircon chronological data from the East China Sea with published detrital U–Pb ages of major rivers in East Asia. Through this analysis, we have been able to reconstruct the provenance changes of sediments in the East China Sea during this crucial period. We have identified two large-scale and three small-scale denudation surfaces that developed in the Pinghu and lower Huagang Formations. These surfaces indicate that sediments were also derived from underlying strata and bedrock, particularly in the lower Pinghu and lower Huagang Formations. The newly acquired detrital zircon U–Pb age range was found to be roughly similar, ranging from 36.2 ± 0.7 to 2954.0 ± 30.3 Ma. The age peaks of the lower Pinghu Formation were more consistent, while the middle, upper Pinghu Formation, and lower Huagang Formation exhibited multiple age peaks. Comparing the compiled zircon U–Pb age peaks of the Chuanjiang segment of the upper Yangtze River with those of the East China Sea Shelf Basin, we found relative similarity. Additionally, the younger zircon grains with ages <500 Ma in the east Cathaysia catchment showed similarities with the East China Sea Shelf Basin. In terms of provenance contribution, the sediments of the lower Pinghu Formation were predominantly provided by the adjacent uplifts in the east Cathaysia catchment, with the Chuanjiang segment also playing a significant role. From the middle Pinghu Formation onwards, the provenance from the Chuanjiang segment became dominant, accounting for over 90 % of the sediments. However, this influence was limited to the northern part of the study area. This suggests a substantial increase in the Yangtze River catchment during this period, potentially related to the complete connection of the modern Yangtze River. • Massive Chuanjiang segment sediments were deposited since the middle Pinghu Formation. • East Cathayisa catchment and adjacent uplift provenance dominant in the lower Pinghu Formation. • The provenance evolution of the Pinghu Formation is related to the birth of modern Yangtze River. [ABSTRACT FROM AUTHOR]

• We prepared a β-cyclodextrin/quercetin inclusion compound and formed nanofilms by electrospinning. • The nanofilm was uniform and had a good nanofiber structure. • Various characterization methods confirmed that the quercetin was embedded in the nanofilm. • Quercetin was slowly released from the nanofilm and retained its antibacterial activity. Quercetin has various biological activities, but its poor water solubility and stability limit its applications. In this study, β-cyclodextrin was used as the host and quercetin was encapsulated in its cavity to prepare an inclusion compound. Then, a nanofilm was formed using electrospinning. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric differential scanning calorimetry (TG-DSC) were used to characterize the properties of the inclusion compound nanofilms. SEM images showed that the nanofilm prepared by optimizing the electrospinning process parameters had a good nanofiber structure. XRD, FTIR and TG/DSC characterization of the nanofilm showed that quercetin was encapsulated in the cavity of β-cyclodextrin and was present in the nanofilm. The quercetin was slowly released from the nanofilm and still had good bacteriostatic effects on Staphylococcus aureus and Escherichia coli , indicating that the process of embedding and electrospinning did not affect the antibacterial activity of quercetin. [ABSTRACT FROM AUTHOR]

Penyanling is made up of Smilacis Glabrae Rhizoma (SG, from Smilar glabra Roxb.), Angelicae Sinensis Radix (AS, from Angelica sinensis (Oliv.) Diels), Salviae Miltiorrhizae Radix et Rhizoma (SM, from Salvia miltiorrhiza Bunge), Sargentodoxae Caulis (SC, from Sargentodoxa cuneata (Oliv.) Rehd.et Wils.), Linderae Radix (LR, from Lindera aggregata (Sims) Kosterm.), Paeoniae Radix Rubra (PR, from Paeonia lactiflora Pall.), Sparganii Rhizoma (SR, from Sparganium stoloniferum (Graebn.) Buch.-Ham.), Corydalis Rhizoma (CoR, from Corydalis yanhusuo W. T. Wang), Cyperi Rhizoma (CyR, from Cyperus rotundus Linn.), Glycyrrhizae Radix et Rhizoma (GR, from Glycyrrhiza uralensis Fisch.), and Patrinia Scabiosaefolia (PS, from Patrinia scabiosaefolia Fisch. ex Trev.) recorded in Chinese Pharmacopoeia. It has been used on pelvic inflammatory disease (PID) for more than twenty years. Aim of the study : This study was carried out to illustrate its pharmacological action and clarify its substantial composition. The anti-inflammatory effects of Penyanling were studied on a PID rat model and a lipopolysaccharides (LPS)-stimulated THP-1 cell line. Histological changes and levels of inflammatory factors in the uterine tube of the PID rat were examined. Levels of nuclear factor-kappa B (NF-κB) in the nuclear of THP-1 cells and NF-κB, IκB-α, and FPR2 in the cytoplasm were tested by Western blot analysis. Substances within Penyanling were scanned with liquid chromatography-quadrupole-time of flight-mass spectrometry (LC-Q-TOF-MS). The contents of total flavonoids, phenolics, and saponins were quantified. The anti-inflammatory effects of Penyanling were observed on PID rats, such as suppressing the infiltrations of lymphocytes and neutrophils in the uterine tube, decreasing the release of interleukin (IL)-1β, IL-6, IL-8, and monocyte chemotactic protein (MCP)-1, and promoting the production of lipoxin A 4 (LXA 4). On the other hand, Penyanling regulated the activity of NF-κB signal pathway on the LPS-stimulated THP-1 cell line, which suggested the potential mechanism of its anti-inflammatory effect. Besides, it could promote the expression of formyl peptide receptor 2 (FPR2), which suggested its effect on enhancing the resolution of inflammation. Seventy-six substances were identified by their accurate molecular weights, mass fragment patterns, retention times, and standards if available. Most of these substances were flavonoids, phenolics, saponins, and alkaloids. The contents of total flavonoids, phenolics, and saponins within Penyanling were 0.186, 1.371, and 4.321 mg/mL, respectively. Penyanling showed an anti-inflammatory effect on PID, and its potential mechanism involved suppressing NF-κB signal pathway and promoting the resolution of inflammation. The main substances within it were flavonoids, phenolics, saponins, and alkaloids. Image 1 • Penyanling showed antiinflammatoy effect on PID rat. • Penyanling can suppress NF-κB pathway and promote inflammation resolution on PID rat. • Main substances within Penyanling were flavonoids, phenolics, saponins, and alkaloids. [ABSTRACT FROM AUTHOR]

• A fast responsive and accurate model for fuel cell dynamic is presented. • Statistical analyses of voltage oscillation were carried out. • Effects of the system's pre-setting parameters were intensively investigated. • Effects of the load variations on the model's responses were thoroughly discussed. • A working zone regulating the system's pre-setting and load variations is presented. The least squares support vector machine method has been successfully applied to modeling the transient behavior of polymer electrolyte fuel cells; this paper analyzes the credibility and definition of its reliable working zone when dealing with multiple load changes. The transient model based on the least squares support vector machine is initially established. Then, the effects of the fuel cell system's setup and exterior load behavior on the transient model are investigated. Artificial data from experimentally-validated Simulink simulations are used, by which extreme working conditions could be taken into account. We found that the fuel cell system's setup with intensive sampling brings about better model performance than that with a sparse sampling interval, as sharp peaks are well characterized when intensive sampling is applied and more information on the fuel cell system is provided to the transient model. Furthermore, the performance of the transient model is better when smoother load changes are imposed on the system, and so a large ramp time and small ramp value are preferable. A working zone for a least squares support vector machine to model polymer electrolyte fuel cell is defined, for which an absolute error is used. Based on the acceptable level of error in the fuel cell system, a set of feasible combinations of its setup and exterior load changes is regulated. Accuracy in the transient model is achieved when the fuel cell runs within the working domain. [ABSTRACT FROM AUTHOR]

Herba Patriniae has been used for thousands of years in China as a traditional Chinese medicine with heat-clearing and detoxicating effects. It is applied widly for the treatment of rheumatoid arthritis, diarrhea, acute hepatitis, pelvic inflammatory disease and ulcerative colitis in clinic. Two species, namely Patrinia scabiosaefolia Fisch. (PS) and Patrinia villosa Juss. (PV) from the Caprifoliaceae family, are considered as Herba Patriniae in the pharmaceutical industry. This paper aims to comprehensively outline the traditional uses, botanical description, phytochemistry, pharmacology, toxicology, quality control, pharmacokinetics and patents of Herba Patriniae, and elaborate the same/different characteristics between PS and PV. Detailed information of Herba Patriniae was collected from various online databases (Pubmed, Web of Science, Google Schola, China National Knowledge Infrastructure Database, National Intellectual Property Administration, PRC National Medical Products Administration), and those published resources (M.Sc. Thesis and books). A total of 233 compounds have been identified in Herba Patriniae, including triterpenoid saponins, flavonoids, organic acids, iridoids, and volatiles. A very distinct difference was observed, that PS is rich in triterpenoid saponins and volatiles, while PV contains more flavonoids. Two source species of Herba Patriniae gave similar pharmacological effects on anti-cancer, anti-inflammatory, antioxidant, antimicrobial, sedative and hypnotic effects. But there were no reports were on antipruritic, proangiogenic and anti-diarrheal effects for PS , and no studies on anti-diabetic effects for PV. Generally, Herba Patriniae showed non-toxic in the clinical dose, but mild side effects, such as temporary leukopenia, dizziness and nausea, could be found when large and excessive dosage is used. A variety of compounds have been quantified for the quality control of PS and PV. The variety, growth environment, growth time, and harvest time not only affected the contents but also the pharmacological activities of the bioactive compounds. In the past year, patents for compositions containing PV and PS have been filed, mainly involving human health, hygiene, agriculture, and animal husbandry. Unfortunately, the research on pharmacokinetics is insufficient. Only the prototype components and metabolites were repored after intragastric administration of total flavonoids extract from PV in rats. Herba Patriniae has displayed a significant medicinal value in clinic, but the differences in phytochemistry, pharmacological effects and the content of compounds have been found between two official recorded species. About side effects and pharmacokinetic characteristics, the differences between two species have not been well studied. For a better clinical use of Herba Patriniae, it is urgent to establish systematic pharmacology, quality control, pharmacokinetics, and clinical researches on the same/different characteristics between PS and PV. Image 1 [ABSTRACT FROM AUTHOR]

As carbon dioxide (CO2) adsorbents, porous materials with high specific surface areas and abundant CO2-philic groups always exhibit high CO2 capacities. Based on this consensus, a category of oxygen-rich macroporous carbon foams was fabricated from macroporous resorcinol-formaldehyde resins (PRFs), which were obtained via an oil-in-water concentrated emulsion. By the active effect of potassium hydroxide (KOH) at high temperatures, the resultant carbon foams (ACRFs) possessed abundant micropores with rich oxygen content simultaneously. At the same time, most of the ACRFs could retain the marcoporous structure of their precursor. It is found that porosity of ACRFs was mainly determined by carbonization temperature, and the highest specific surface areas and total pore volume of ACRFs could reach 2046 m2/g and 0.900 cm3/g, respectively. At 273 K, ACRFs showed highest CO2 capacity as 271 mg/g at 1 bar and 91.5 mg at 15 kPa. Furthermore, it is shown that the ultra-micropore volume was mainly responsible for the CO2 capacities of ACRFs at 1 bar, and CO2 capacities at 15 kPa were mainly affected by the oxygen content. It is also found that the presence of macropores would accelerate ACRFs adsorbing CO2. This study provides ideas for designing a porous CO2 adsorbent. [ABSTRACT FROM AUTHOR]

This study investigates the influence of freeze-thaw (FT) cycles on the (i) microstructure, (ii) soil water characteristics, and (iii) sensitivity of the volumetric strain and mechanical properties to moisture content for a compacted clay. The mechanical properties herein include resilient modulus (M R), unconfined compression strength (q u), and reloading modulus (E 1%) and stress (S u1%) at 1% strain. Specimens were compacted at optimum moisture content and subjected to different FT cycles (i.e. 0, 1, 3, and 10 cycles). Scanning electron microscopy (SEM) and mercury intrusion porosimetry (MIP) were performed to reveal the evolution of the microstructure during FT cycles. Specimens were then wetted or dried to different suction (s) and degree of saturation (S r) values to obtain the (i) soil water characteristics using filter paper method and (ii) M R , q u , E 1% , and S u1% using cyclic and static triaxial tests. Experimental results demonstrate that FT cycles induce cracks that are tens of microns in dimension, which reduce specimens' water retention capacity and the volumetric strain upon wetting and drying. Mechanical properties also reduce significantly and become less sensitive to the s and S r after FT cycles. A model was used to predict the variation of the M R , q u , E 1% and S u1% with s and S r for specimens subjected to different FT cycles. An attenuation coefficient χ FT was proposed to describe the FT-induced degradation in the q u , E 1% , S u1% , and M R. It was found that the χ FT for different mechanical properties are consistent. The evolution of their χ FT with FT cycles can be described by a uniform empirical equation. The study presented in this paper is useful for the rational understanding and prediction of the hydromechanical behaviors of compacted clay taking account of the influence of FT cycles. • Freeze-thaw (FT) cycles generate cracks that are tens of microns in dimension. • FT cycles reduce soils' water retention capacity and mechanical properties. • Mechanical properties are less sensitive to moisture changes after FT cycles. • Models were proposed to predict mechanical properties considering FT influences. [ABSTRACT FROM AUTHOR]

• The particle disintegration of cooked milled rice plays key role in starch digestibility. • Low GI rice varieties differentiated by the reaction rate of initial fast phase. • Less small/intermediate disintegrated cooked grain particles give slower starch digestibility. • Particle disintegration parameter Q-300 can predict GI of cooked rice grain digestibility. This study investigated the particle disintegration of cooked milled rice during in vitro digestion to identify its potential for rapidly predicting glycaemic index (GI). Milled grains and flour of rice with varying GI were cooked, stirred and subjected to digestion followed by kinetics analyses. Despite variations in physicochemical parameters (typically amylose content), flours showed a single-phase-digestion rate (k , ∼0.12 min−1) which did not vary significantly between varieties. In contrast, intact grains were disintegrated into small/intermediate (d < 30 μm, 30 < d < 300 μm) and large (d > 300 μm) particles. The small/intermediate particles comprising 50–70 % starch were initially-digested (0−20 min) at a fast k -f (∼0.05−0.10 min−1), which enabled to differentiate rice digestibility; whereas the large was latter-digested (20–180 min) at a slow k –s (∼0.04 min−1). The sum-ratio of disintegrated-particle 0−300 μm (Q-300) correlated positively with clinical GI values, allowing for a digestibility prediction of intact milled rice grain. [ABSTRACT FROM AUTHOR]

A novel and sensitive method for the selective determination of Cr(VI) and non-chromatographic speciation of Cr(VI) and Cr(III) was developed based on chemical vapor generation (CVG) in KBH 4 -acid system for sample introduction into an inductively coupled plasma mass spectrometer (ICP-MS) for detection. The CVG of Cr(VI), rather than Cr(III), was found to be remarkably enhanced in the presence of sodium diethylaminodithioformate (DDTC). After the oxidation of Cr(III) to Cr(VI) by KMnO 4 , the quantitation of Cr(III) could be obtained based on the difference between the concentration of total chromium and that of Cr(VI). Parameters affecting the CVG reaction and determination of Cr(VI) were evaluated in detail, including the concentrations of DDTC, hydrochloric acid and KBH 4 , the sample flow rate, as well as the length of reaction and transferring tubing. Under optimal conditions, the CVG efficiency and the limit of detection (LOD) of Cr(VI) were found to be 28% and 0.2 ng mL−1, respectively. The relative standard deviations for seven replicate measurements of 20 ng mL−1 of Cr(Ⅵ) was 1.8%. Furthermore, with excess DDTC (100 μg mL−1) added to the test solutions, possible interferences from Cu2+ (up to 400 ng mL−1) could be eliminated. The proposed method was thus successfully applied to the determination of Cr(VI) in three real water samples and one certified reference water sample, as well as two simulated water samples of Cr(VI) and Cr(III), all with satisfactory results. The possible reasons were discussed for the varied degrees of enhancement between Cr(III) and Cr(VI). Image 1 • Trace chromium was determined by chemical vapor generation-ICPMS. • Chemical vapor generation efficiency of Cr(VI) was selectively enhanced with DDTC. • Non-chromatographic speciation analysis of Cr(III) and Cr(VI) can be realized via oxidation of Cr(III) to Cr(VI) by KMnO 4. • It was used for quantitation of Cr(VI) and speciation analysis of Cr(VI)/Cr(III) in water samples. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) have recently emerged as an important candidate for cell therapy and tissue regeneration. However, some limitations in translational research and therapies still exist, such as insufficient cell supply, inadequate differentiation potential, and decreased immune capacity, all of which result from replicative senescence during long-term in vitro culture. In vitro, stem cells lack a protective microenvironment owing to the absence of physical and biochemical cues compared with the in vivo niche, which provides dynamic physicochemical and biological cues. This difference results in accelerated aging after long-term in vitro culture. Therefore, it remains a great challenge to delay replicative senescence in culture. Constructing a microenvironment to delay replicative senescence of MSCs by maintaining their phenotypes, properties, and functions is a feasible strategy to solve this problem, and has made measurable progress both in preclinical studies and in clinical trials. Here, we review the current knowledge on the characteristics of senescent MSCs, explore the molecular mechanisms of MSCs senescence, describe the niche of MSCs, and discuss some current microenvironment strategies to delay MSCs replicative senescence that can broaden their range of therapeutic applications. [ABSTRACT FROM AUTHOR]

In the existing millimeter-wave (mmWave) wireless positioning systems, the method based on sparse Bayesian learning (SBL) uses the channel sparsity to estimate the parameters required for positioning, such as angle of arrival (AOA) and time delay, but most existing SBL solutions only consider the angle sparsity. In this paper, we consider the joint sparsity of the angle domain and time delay domain to propose an improved SBL algorithm by using a new two-dimensional adaptive grid refinement method in the SBL framework. This algorithm solves the grid mismatch problem caused by the fixed grid in the traditional SBL method, and reduces the algorithm complexity of the off-grid SBL (OGSBL) algorithm. We also obtain the Cramér-Rao bound (CRB) of AOA, time delay and position estimation based on the mmWave multipath signals to analyze the estimation errors. Simulation results show that the performance of the proposed algorithm is better than existing algorithms and can approach CRB. [ABSTRACT FROM AUTHOR]

Friction welding is a popular process for joining metal and polymer work pieces by rubbing them against each other. This way, friction heat is generated in a zone of the faying surfaces, thinner than 1 mm. After cooling down, the heated surfaces establish a tight and strong bond. To improve this joining process, a method is desirable allowing measuring generated temperature and shear stress in the zone between the joining work pieces. Unfortunately, this is a very difficult task because the welding zone cannot be accessed with a sensor without significantly altering the process and thereby the desired measurement results. This paper describes how shear stress and temperature change generated by rubbing polymer pieces in a friction welding machine have been measured between the faying surfaces by employing sensor foils from the piezoelectric and pyroelectric polymer polyvinylidene fluoride (PVDF). This way, heating and cooling rates, pressure rise of the pneumatic system, frequency rise of the starting machine, the duration of starting and stopping, the damping of the vibrations after the drive was stopped, and the stress generated by the pullback of the machine head have been measured. A careful characterization of the sensor was necessary to enable distinguishing the measured voltage due to straining, shearing and temperature change. [ABSTRACT FROM AUTHOR]

• Prediction model for fuel cell dynamic behavior is presented. • Effects of the system's pre-setting parameters were intensively investigated. • Effects of the load variations on the model's responses were thoroughly discussed. • Guidance for future application of the transient voltage model was provided. An investigation into the credibility and suitability of a transient voltage model that characterizes the dynamic behavior of polymer electrolyte fuel cells was carried out by means of quantitative and qualitative validations. The least squares support vector machine method was then used to construct a transient voltage model of a fuel cell in the first phase, including a validation based on experimental data obtained from a test rig. In the second phase, a thorough discussion of the effect of the fuel cell's operating conditions and the exterior load changes on the model's performance was implemented. For this phase, the influences of the sampling interval and ramp ratio are discussed and determined following a large number of tests under a variety of operating conditions. The results show that sampling with short time intervals is an effective way to improve the model's performance, and a smoother change to the exterior load is more likely to be approximated by the least squares support vector machine model. Moreover, the voltage model is sensitive to the ramp value by comparison to the ramp time. Suggestions for future applications of the transient voltage models are also provided. For a given combination of load changes, the sampling interval should be managed within a range to reach the demand data that satisfies the voltage accuracy. On the other hand, for a determinate sampling interval, the dynamic change of the load should be restricted within a limit to ensure that the model error is lower than the demand value. [ABSTRACT FROM AUTHOR]

The armchair metallic and semiconducting toroidal carbon nanotubes (TCNs) coupled with Majorana bound states (MBSs) under the perturbation of microwave fields (MWFs) have been investigated, and the photon-assisted features relating to tunneling current, differential conductance, and shot noise have been evaluated numerically. For the semiconducting TCN system, the photon-induced resonant peaks emerge at the conductance valley around zero-bias voltage, and the semiconducting energy gap can be closed by MBSs and MWFs. For the metallic TCN system, normal tunneling and Andreev reflections cooperate to generate a hybridized zero-bias conductance. The periodic behavior of conductance versus magnetic flux is intimately dependent on the metallic and semiconducting TCN structures. Applying MWFs on the TCN system coupled with MBSs can enhance the shot noise largely compared with the case without MBSs. The Fano factor appears two kinds of triple-peak oscillation structure when MBSs are connected to the semiconducting TCN, and the application of MWFs enhances the maximum value of Fano factor. The shot noise jumps at zero bias, and the steps are smeared by the photon absorption and emission. The Fano factor is enhanced by MBSs, and it increases rapidly to exhibit a giant value around zero bias. • Toroidal carbon nanotubes (TCNs) coupled with Majorana bound states (MBSs) under the perturbation of microwave fields have been investigated. • Dynamic current and shot noise formulas have been derived for investigating specific output information of coupled MBSs. • Semiconducting and metallic TCN systems exhibit concrete signatures of MBSs resulting from photon-assisted Andreev reflections. • Enhancement of shot noise and large Fano factor appears in the TCN–MBSs system accompanying with photon absorption and emission. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO), a novel two-dimension carbon nanomaterial, has showed tremendous potential for utilization in intelligent manufacturing and environmental protection. In parallel, tris(1,3–dichloro–2–propyl) phosphate (TDCIPP) is widely distributed in the water environment and represents a great threat to ecosystem health. However, the related knowledge remained absent regarding the impact of GO on the biological risks of TDCIPP. Herein, GO significantly reduced the mortality and malformation rates of zebrafish induced by TDCIPP maximumly by 28.6% and 41.8%, respectively. Decreased mitochondrial respiratory chain (MRC) enzyme and ATP activity induced by TDCIPP were mitigated by GO. Integrating proteomics and metabolomics revealed TDCIPP obviously induced the downregulation of the proteins and metabolites involved in the cytoskeleton, mitochondrial function, carbohydrate and amino acid metabolism, and the TCA cycle, but the alterations were attenuated by GO. GO primarily promoted MRC activity, carbohydrate metabolism, and fatty acid β–oxidation, thus activating the energy metabolism of zebrafish and leading to antagonistic effects on the developmental toxicity of TDCIPP. These results provide a novel view on the co–exposure of GO with other pollutants and promote the reconsideration of the environmental risks of GO. Unlabelled Image • GO reduced the mortality and malformation rate of zebrafish induced by TDCIPP. • GO relieved the mitochondria damage and MRC enzyme inhibition induced by TDCIPP. • GO co-exposure promoted the carbohydrate metabolism and fatty acid β–oxidation. • GO activated the energy metabolism leading to the antagonistic toxicity with TDCIPP. [ABSTRACT FROM AUTHOR]

Abstract: In self-identified white patients with major depressive disorder (N=126) treated with open-label duloxetine (60–120mg/d), a significant association of (P=0.020) of a composite risk score (based on SLC6A2 rs5569 [G1287A] AA, HTR1A rs6295 [C(−1019)G] GG, and COMT rs174697 AA/AG) with 17-item Hamilton Depression Rating Scale total score change from baseline to 12 weeks was observed. [Copyright &y& Elsevier]

We propose a scheme to achieve a kind of nontrivial two-qubit operation using controllable electrons in doubledot molecules coupled to a transmission line resonator. The implemented operation is geometrical in nature and insensitive to the state of the transmission line resonator. In particular, we are able to avoid conventional dispersive coupling so that a high speed gate operation can be achieved, which is important in view of decoherence. Meanwhile, we are able to further generalize the operation to an arbitrary phase case by dynamic decoupling with two sequences. [ABSTRACT FROM AUTHOR]

Sheet-like ZSM-5 zeolites with varied b-axis thicknesses (92, 160, 264 and 407 nm, respectively) and equivalent Si/Al molar ratios (ca. 150) were prepared using urea as additive in the aluminosilicate gels, and studied with respect to their performance in benzene alkylation with methanol. The ZSM-5 samples have similar textural properties and acidic properties. Catalytic tests show that these catalysts exhibit comparable benzene conversions of ca. 64% at 400 °C and WHSV of 2 h−1. The correlation between the selectivity of toluene and xylene and the ZSM-5 crystal size in the b-axis can be established. As the b axis length is decreased from 407 to 92 nm, the selectivity to toluene and xylene increases obviously from 80.3 to 87.4%, which is attributed to enhanced diffusion property of ZSM-5 zeolite. This finding provides an alternative strategy to improve the selectivity of toluene and xylene in the alkylation of benzene with methanol over ZSM-5-based catalysts. [ABSTRACT FROM AUTHOR]

Background: Secondary immunodeficiency can arise from various clinical conditions that include HIV infection, chronic diseases, malignancy and long-term use of immunosuppressives, which makes the suffering patients susceptible to all types of pathogenic infections. Other than HIV infection, the possible pathogen profiles in other aetiology-induced secondary immunodeficiency are largely unknown. Methods: Medical records of the patients with secondary immunodeficiency caused by various aetiologies were collected from the First Affiliated Hospital of Nanchang University, China. Based on these records, models were developed with the machine learning method to predict the potential infectious pathogens that may inflict the patients with secondary immunodeficiency caused by various disease conditions other than HIV infection. Results: Several metrics were used to evaluate the models' performance. A consistent conclusion can be drawn from all the metrics that Gradient Boosting Machine had the best performance with the highest accuracy at 91.01%, exceeding other models by 13.48, 7.14, and 4.49% respectively. Conclusions: The models developed in our study enable the prediction of potential infectious pathogens that may affect the patients with secondary immunodeficiency caused by various aetiologies except for HIV infection, which will help clinicians make a timely decision on antibiotic use before microorganism culture results return. [ABSTRACT FROM AUTHOR]

In biological or physical systems, the intrinsic properties of oscillators are heterogeneous and correlated. These two characteristics have been empirically validated and have garnered attention in theoretical studies. In this paper, we propose a power-law function existed between the dynamical parameters of the coupled oscillators, which can control discontinuous phase transition switching. Unlike the special designs for the coupling terms, this generalized function within the dynamical term reveals another path for generating the first-order phase transitions. The power-law relationship between dynamic characteristics is reasonable, as observed in empirical studies, such as long-term tremor activity during volcanic eruptions and ion channel characteristics of the Xenopus expression system. Our work expands the conditions that used to be strict for the occurrence of the first-order phase transitions and deepens our understanding of the impact of correlation between intrinsic parameters on phase transitions. We explain the reason why the continuous phase transition switches to the discontinuous phase transition when the control parameter is at a critical value. [ABSTRACT FROM AUTHOR]

[Display omitted] • This paper mainly discusses the cells based on the inflammatory mechanism to discuss their functions after ICH. • Microglia can interact with a wide range of cells, which is important for both disease development and treatment. • We believe that exploring multi-mechanism and multi-cell regulated drugs may be the future development trend. The inflammatory mechanism of intracerebral hemorrhage (ICH) has been widely studied, and it is believed that the regulation of this mechanism is of great significance to the prognosis. In the early stage of the acute phase of ICH, the release of a large number of inflammatory factors around the hematoma can recruit more inflammatory cells to infiltrate the area, further release inflammatory factors, cause an inflammatory cascade reaction, aggravate the volume of cerebral hematoma and edema and further destroy the blood–brain barrier (BBB), according to this, the crosstalk between cells may be of great significance in secondary brain injury (SBI). Because most of the cells recruited are inflammatory immune cells, this paper mainly discusses the cells based on the inflammatory mechanism to discuss their functions after ICH, we found that among the main cells inherent in the brain, glial cells account for the majority, of which microglia are the most widely studied and it can interact with a variety of cells, which is reflected in the literature researches on its pathogenesis and treatment. We believe that exploring multi-mechanism and multi-cell regulated drugs may be the future development trend, and the existing research, the comparison and unification of modeling methods, and the observation of long-term efficacy may be the first problem that researchers need to solve. [ABSTRACT FROM AUTHOR]

Background: (Pro)renin receptor (PRR) is highly expressed in renal tubules, which is involved in physiological and pathological processes. However, the role of PRR, expressed in renal tubular epithelial cells, in diabetic kidney disease (DKD) remain largely unknown. Methods: In this study, kidney biopsies, urine samples, and public RNA-seq data from DKD patients were used to assess PRR expression and cell pyroptosis in tubular epithelial cells. The regulation of tubular epithelial cell pyroptosis by PRR was investigated by in situ renal injection of adeno-associated virus9 (AAV9)-shRNA into db/db mice, and knockdown or overexpression of PRR in HK-2 cells. To reveal the underlined mechanism, the interaction of PRR with potential binding proteins was explored by using BioGrid database. Furthermore, the direct binding of PRR to dipeptidyl peptidase 4 (DPP4), a pleiotropic serine peptidase which increases blood glucose by degrading incretins under diabetic conditions, was confirmed by co-immunoprecipitation assay and immunostaining. Results: Higher expression of PRR was found in renal tubules and positively correlated with kidney injuries of DKD patients, in parallel with tubular epithelial cells pyroptosis. Knockdown of PRR in kidneys significantly blunted db/db mice to kidney injury by alleviating renal tubular epithelial cells pyroptosis and the resultant interstitial inflammation. Moreover, silencing of PRR blocked high glucose-induced HK-2 pyroptosis, whereas overexpression of PRR enhanced pyroptotic cell death of HK-2 cells. Mechanistically, PRR selectively bound to cysteine-enrich region of C-terminal of DPP4 and augmented the protein abundance of DPP4, leading to the downstream activation of JNK signaling and suppression of SIRT3 signaling and FGFR1 signaling, and then subsequently mediated pyroptotic cell death. Conclusions: This study identified the significant role of PRR in the pathogenesis of DKD; specifically, PRR promoted tubular epithelial cell pyroptosis via DPP4 mediated signaling, highlighting that PRR could be a promising therapeutic target in DKD. [ABSTRACT FROM AUTHOR]

We previously revealed that hydrogen sulfide (H 2 S) attenuates chronic stress-induced cognitive impairment, but the underlying mechanism needs to be further clarified. Growth differentiation factor 11 (GDF11) plays an important regulatory role in cognitive function and that hippocampal NLRP3/caspase-1-mediated pyroptosis contributes to the pathogenesis of cognitive impairment. Hence, this research aimed to explore whether promoting GDF11 levels and suppressing hippocampal NLRP3/caspase-1-mediated pyroptosis mediate H 2 S to alleviate chronic stress-induced cognitive impairment. Sprague–Dawley rats were subjected to unpredictable chronic mild stress lasting four weeks to establish an animal model of chronic stress-induced cognitive impairment. Behavioral performance was assessed by the Y-maze test and the novel object recognition test. The expression levels of proteins were analyzed by Western blot analysis. The levels of IL-1β and IL-18 in the hippocampus were measured by ELISA. NaHS upregulated the expression of GDF11 in the hippocampus of chronic unpredictable mild stress (CUMS)-exposed rats. Silencing GDF11 blocked NaHS-improved cognitive impairment in CUMS-exposed rats, according to the Y-maze test and the novel object recognition test. Furthermore, NaHS mitigated NLRP3/caspase-1-mediated pyroptosis in the hippocampus of CUMS-exposed rats and this effect was reversed by silencing GDF11. Moreover, overexpression of GDF11 alleviated CUMS-induced cognitive impairment and NLRP3/caspase-1-mediated hippocampal pyroptosis. GDF11 mediates H 2 S to attenuate chronic stress-induced cognitive impairment via inhibiting hippocampal NLRP3/caspase-1-mediated pyroptosis. [Display omitted] • H 2 S upregulates GDF11 expression and ameliorates pyroptosis in CUMS-exposed rats. • Silencing GDF11 blocks H 2 S to prevent cognitive dysfunction in CUMS-exposed rats. • Silencing GDF11 reverses H 2 S-blocking pyroptosis in CUMS-exposed rats. • GDF11 overexpression ameliorates the cognitive impairment in CUMS-exposed rats. • GDF11 overexpression inhibits pyroptosis in CUMS-exposed rats. [ABSTRACT FROM AUTHOR]

The increasing global occurrence of cyanobacterial blooms, attributed primarily to human-induced nutrient enrichment, significantly degrades freshwater ecosystems and poses serious risks to human health. The current study examined environmental variables and cyanobacterial biovolume (B Cyano) of 28 shallow lakes in the eastern China plains during the spring and summer of 2018. We used a 95% quantile regression model to explore season-specific response of B Cyano to total nitrogen (TN), or total phosphorus (TP), and robust linear relationships were observed between log(B Cyano +0.001) and log(TN), or log(TP) in both spring and summer periods. Based on these regressions, regional-scale and season-specific TN and TP thresholds are proposed for these lakes to ensure the safety for recreational waters and drinking water source. However, actual B Cyano for a given concentration of TN (or TP) for many observations were considerably lower than the results of the 95% regression model predict, indicating that other factors significantly modulated nutrient limitation of B Cyano. Generalized additive model and quantile regression model were used together to explore potentially significant modulating factors, of which lake retention time, macrophytes cover and N: P ratio were identified as most important. Thus, it is necessary to develop type-specific nutrient thresholds with the consideration of these significant modulating factors. Furthermore, nutrient-B Cyano relationships of our studied lakes with lake retention time>100 days and no macrophyte were further explored and nutrient thresholds of this lake type were proposed. Nutrient thresholds proposed in this study may play an essential role in achieving a cost-effective eutrophication management for shallow lakes both in the eastern China plains and elsewhere with similar climatic background. On a broader scale, the approaches and findings of this study may provide valuable reference to formulate reasonable nutrient reduction targets for other ecoregions with different climatic conditions. Image 1 • Regional-scale nutrient-cyanobacteria interactions were examined using a 95% quantile model. • Cyanobacterial growth in shallow lakes was limited by both nitrogen and phosphorus. • Nutrient limitation of cyanobacteria was considerably modulated by flushing. • Nutrient targets were proposed for shallow lakes in the eastern China plains. [ABSTRACT FROM AUTHOR]

Eutrophication and associated algal blooms are principal environmental challenges confronting lakes in China, particularly in the Eastern Plains ecoregion. The empirical relationships between nutrient and chlorophyll a (Chl a) level and Secchi depth (SD) are widely used as a theoretical basis for lake eutrophication management. However, these relationships are largely influenced by hydromorphological conditions and biogeochemical processes. Thus, there is a need to establish a type-specific understanding of these interactions. In the current study, lakes in the Chinese Eastern Plains ecoregion were subdivided into four lake types according to water retention time (LRT), water depth, and water area. Regression analyses indicated that the impacts of nutrient (total nitrogen, TN; total phosphorus, TP) concentrations on summer Chl a were significantly reduced in lakes with high inorganic suspended solids (ISS) (P <0.05). Meanwhile, the decrease in SD in these lakes were found to relate mainly to non-algal turbidity. In lakes characterized by both short LRT and high ISS content, the Chl a exhibited limited response to nutrients. In contrast, in lakes with low ISS content and long LRT, the observed slopes of both Chl a =f(TP) and SD=f(Chl a) were significantly steeper (P < 0.05). The factors limiting summer algal growth and the development of type-specific nutrient criteria (TN and TP) of all four investigated lake types in the Eastern Plains ecoregion are discussed in the context of specific nutrients. Based on these results, we establish type-specific eutrophication assessment equations of TN, TP, Chl a , and SD in our study lakes. Our results may provide essential information for achieving the cost-effective eutrophication management of lakes both in the Eastern Plains ecoregion and elsewhere with similar climatic and hydromorphological conditions. Moreover, we believe that the subdivision of lakes to allow type-specific eutrophication management framework may prove valuable for other ecoregions where the interpretation of empirical nutrient-Chl a and SD relationships suffer from similar serious limitations. • General eutrophication management is ill-suited for lakes in Easterns Plain ecoregion: • The type-specific nutrient-chlorophyll a -Secchi depth relationships were explored. • A type-specific nutrient reduction and eutrophication assessment was proposed. [ABSTRACT FROM AUTHOR]

A non-destructive and comprehensive 13C isotopic evaluation approach based on 1H NMR spectroscopy was developed. The carbon isotope distribution (CID) of most of the components (S/N ≥ 1000) in food matrices were evaluated using frequency distribution of peak area ratios (PAR) of decoupling to non-13C-decoupling spectra at natural abundance. The approach was applied successfully to vinegar and it was found that the PAR of fermented vinegars is obviously narrower than that of the blended one and the one produced via chemically defined culture medium. Besides, the extra additives can also be evaluated by their characteristic PAR values. It was found that the sugars are the most commonly added components into the blended vinegars. The results obtained from the developed approach show good validity (baseline effect, RSD < 0.1%) and internal reproducibility (RSD < 0.1%). Practicability of the method is confirmed by gas chromatography-isotope ratio mass spectrometry (GC-IRMS) detection method. The results imply that the proposed approach could be used not only for the discrimination but also for the primary authentication of the blended components in the fermented food matrices. Image 1 • A non-destructive and comprehensive 13C isotopic evaluation approach based on 1H NMR spectroscopy was developed. • The carbon isotope distribution (CID) of most components (S/N ≥ 1000) in food matrices was evaluated. • CID was determined by using frequency distribution of peak area ratios (PAR) of decoupling to non-13C-decoupling spectrum at natural abundance. • The approach was applied successfully to authenticate the quality of vinegar. • Practicability of the method was confirmed by gas chromatography-isotope ratio mass spectrometry (GC-IRMS). [ABSTRACT FROM AUTHOR]

Applying concepts and methods of bionics to endow autonomous robots with elegant and agile mobility just like natural living beings is gradually becoming a hot research topic in intelligent robot field. Compared with walking, crawling, rolling and other motion modes, jumping performs considerable advantages that can leap across obstacles and move to different heights in agility and flexibility. In this paper, we specifically review the developments of biologically inspired jumping robots in the past decades, and give comprehensive analysis on some key technologies for implementing a practical jumping robot effectively. First, the jumping mechanism of frog (amphibian, quadruped), locust (arthropod, hexapod), kangaroo (mammality, bipedalism) as examples of typical animals good at jumping is introduced and analyzed, from which it is concluded that power sources, limbs coordination and control are key elements for excellent jumping performances, which should be synthetically improved by combination with structure design and model establishment. Then, spring loaded inverted pendulum (SLIP), bio-inspired open-chain and closed-chain multi-linkage as representative jumping mechanical structures, their characteristics are explored accompanied with dynamic analysis. After a detailed analysis to actuators and energy storage devices and a comprehensive summarization to functional and soft materials commonly applied in jumping robots, different control methods and strategies adopted to achieve better jumping performance are reviewed and analyzed, from self-righting, driving control to path planning. Especially, how to analyze the stability of a jumping control system and how to stabilize it are explained theoretically by taking a vertical monopedal jumping robot as an example and via limit cycle analysis. Finally, some feasible and potential future developments in bio-inspired jumping robots are also presented after detailed discussions on current status and existing deficiencies. [ABSTRACT FROM AUTHOR]

• Precompression total strain mainly affects EPS' compressive properties. • Precompression plastic strain mainly affects EPS' rheological properties. • Short-term loads are helpful in attenuating the creep of EPS. • Suggestions for using recycled EPS are provided. This paper investigates the effect of stress history on the compressive and rheological behaviors of EPS geofoam. Short-time, constant-load and constant-strain precompression loadings were applied to impose different types of stress history on EPS samples. These samples were thereafter subjected to rapid compression, creep and stress relaxation tests to reveal their compressive (i.e. stress-strain relationship) and rheological (i.e. creep and stress relaxation) behaviors. Test results showed that (i) the yield strain of EPS increases as the maximum past strain level (precompression strain) increases and the stress-strain behavior of the EPS in the post-yielding range is not affected by its stress history; and (ii) the accumulated plastic strain during precompression decreases the rate of creep and stress relaxation. Based on the observed influence of stress history on the EPS, suggestions on the use of pre-loaded EPS were provided in this study. [ABSTRACT FROM AUTHOR]

Sand mining is a human activity that is increasing in inland waters and has profound effects on entire aquatic ecosystems. However, current knowledge of the effects of sand mining on freshwater lake ecosystems remains limited, especially for biotic communities. Here, we investigated the responses of macroinvertebrates to indiscriminate sand mining in a large shallow lake of China. Our results indicated that sand mining significantly increased the content of suspended particulate matter, total nitrogen, total phosphorus and chlorophyll a in the water column both in the sand mining area and the area adjacent to the dredging activities. While there was significantly lower total nitrogen and the total phosphorus content of the sediment were observed in the sand mining area. In terms of benthic animals, there were reductions of the macroinvertebrate density and biomass of 89.80% and 99.54%, respectively, and there was a considerable decline of the majority of macroinvertebrate taxonomic taxa as well as biological traits observed in the sand mining area due to direct dredging-induced substrate deterioration and high turbidity water. Moreover, in the area adjacent to the dredging activities, dredging-induced high turbidity water also resulted in 28% and 79% decreases in macroinvertebrate density and biomass, respectively, with a significant decrease in the densities of Bivalvia and Polychaeta but an increase in the density of Crustacea. In terms of biological traits, species (e.g., Grandidierella sp. and Sphaerium lacustre) characterized by a small body size, short life cycle and dietary sources mainly from sediment were typically associated with the ecological condition of the indirect effects of the dredging activities. Taxa (e.g., Corbicula fluminea) with a larger body size and longer life cycle that are filter feeders should be favored by the ecological conditions of the reference sites. For biomonitoring of sand mining perturbations, a number of taxonomic and biological trait indicators were proposed in our study based on indicator value analysis, and the general applicability of trait-based indicators was highlighted. We also suggest that the biodiversity indices may be less suitable indicators of sand mining effects. Given the limited understanding of the responses of macroinvertebrates to sand mining in inland freshwaters, we believe that our results may provide important information for biomonitoring of sand mining activities and provide scientific management support to governments. Unlabelled Image • The sand mining effects on macroinvertebrates were examined in a large shallow lake. • Sand mining has induced substantial decline of macroinvertebrates. • Some taxonomic and trait group indicators were individuated to be sensitive to the response of sand mining perturbation. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is an intracellular parasite that infects humans and other warm-blooded animals. Exosomes are endocytic-derived vesicles released by cells, representing an important mode of intercellular communication. In exosomes, specific molecules of proteins, lipids, and mRNAs or miRNAs have been detected, some of which are capable of transferring biologically active molecules to recipient cells. Dendritic cells (DCs) are the only antigen-presenting cells (APCs) that activate the initial immune response. In this study, high-throughput sequencing was used to analyze the exosomal miRNA profile of DC2.4 cells infected with Toxoplasma gondii for 28 h, compared with those of uninfected DC2.4 cells. Differential exosomal miRNAs (DEmiRs) from these two cell groups were analyzed. Through high-throughput sequencing, 3434 DEmiRs were obtained, and 12 stably enriched DEmiRNAs were verified by Reverse Transcription-quantitative Polymerase Chain Reaction (RT-qPCR) and selected for further analysis. The target genes of these 12 miRNAs were predicted with online analysis software and subjected to bioinformatics analyses including protein–protein interaction (PPI) network analysis, key driver analysis (KDA), gene ontology (GO) enrichment, and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. These DEmiRs were found to be associated with a variety of biological processes and signaling pathways involved in host ubiquitin system, innate immunity, biosynthesis, and transferase activity and could be potential biomarkers for T. gondii infection. [ABSTRACT FROM AUTHOR]

The crystallization in a fluidized‐bed crystallizer has recently received increasing interest for separation and purification of crystals. Past investigations on potassium dihydrogen phosphate (KDP) crystallization mainly focused on process efficiency and thermodynamics and less on kinetics. In this paper, the fluidized crystallization technology is used to investigate a KDP crystallization process. The mechanisms involved in crystal formation have been explored by observation of a continuous withdrawal of a suspension containing target crystals having certain size distribution. The crystallization process of KDP is researched to investigate the key parameters (suspension density [MT], solution supersaturation [ΔC], and fluid shear force [expressed by circulation flow rate; Re]) influencing crystal growth, nucleation, and agglomeration process. Three proposed crystallization kinetic models about crystals growth, nucleation, and agglomeration rates are developed and validated against data from the fluidized‐bed crystallizer. Taking advantage of multivariate nonlinear regression analysis, crystallization kinetic parameters are obtained by adopting the kinetic model in fluidized‐bed crystallization process. The comparative research of three crystallization kinetic rates is also studied. The results indicated that the parameters given by the kinetic mathematics model fit well with the experimental data. The error rate between the experimental and calculated value is also controlled within a reasonable range. [ABSTRACT FROM AUTHOR]

In cancer radiation therapy, large tumor motion due to respiration can lead to uncertainties in tumor target delineation and treatment delivery, thus making active motion management an essential step in thoracic and abdominal tumor treatment. In current practice, patients with tumor motion may be required to receive two sets of CT scans – the initial free-breathing 4-dimensional CT (4DCT) scan for tumor motion estimation and a second CT scan under appropriate motion management such as breath-hold or abdominal compression. The aim of this study is to assess the feasibility of a predictive model for tumor motion estimation in three-dimensional space based on machine learning algorithms. The model was developed based on sixteen imaging features extracted from non-4D diagnostic CT images and eleven clinical features extracted from the Electronic Health Record (EHR) database of 150 patients to characterize the lung tumor motion. A super-learner model was trained to combine four base machine learning models including the Random Forest, Multi-Layer Perceptron, LightGBM and XGBoost, the hyper-parameters of which were also optimized to obtain the best performance. The outputs of the super-learner model consist of tumor motion predictions in the Superior-Inferior (SI), Anterior-Posterior (AP) and Left-Right (LR) directions, and were compared against tumor motions measured in the free-breathing 4DCT scans. The accuracy of predictions was evaluated using Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) through ten rounds of independent tests. The MAE and RMSE of predictions in the SI direction were 1.23 mm and 1.70 mm; the MAE and RMSE of predictions in the AP direction were 0.81 mm and 1.19 mm, and the MAE and RMSE of predictions in the LR direction were 0.70 mm and 0.95 mm. In addition, the relative feature importance analysis demonstrated that the imaging features are of great importance in the tumor motion prediction compared to the clinical features. Our findings indicate that a super-learner model can accurately predict tumor motion ranges as measured in the 4DCT, and could provide a machine learning framework to assist radiation oncologists in determining the active motion management strategy for patients with large tumor motion. [ABSTRACT FROM AUTHOR]

This paper investigates the volumetric, microstructural, and shear behaviours of an expansive soil during multiple drying-wetting (DW), freeze–thaw (FT), and drying-wetting-freeze–thaw (DWFT) cycles. Specimens compacted at natural moisture content and dry density were subjected to 1, 4, 6, and 10 DW, FT, or DWFT cycles. Volumetric changes were recorded during the treatments and mercury intrusion porosimetry, and scanning electron microscope tests were conducted to observe the soil's microstructure before and after treatments. As compacted specimens and specimens after different numbers of DW, FT, and DWFT cycles were saturated and sheared under consolidated undrained condition to determine their undrained elastic modulus (Eu), shear strength (qu), total cohesion (c), and friction angle (ϕ). Experimental results show that DW, FT, and DWFT cycles mainly influence the soil's macropores with diameters between 5 and 250 μm. Macropores collapse during DW cycles, which lead to collapse in the soil's global volume. Cracks develop during FT cycles and result in slight swelling in the soil's volume. These two effects offset during DWFT cycles and cause an intermediate volumetric behaviour. The Eu, qu, c, and ϕ decline during DW, FT, and DWFT cycles, and the reduction was most significant during DWFT cycles. They reach an equilibrium after approximately 6 cycles of treatment. A simple normalized model was developed to describe the stress–strain curves considering the influence of DW, FT, and DWFT cycles. Good agreements were achieved between the model predictions and measurements for all stress–strain curves obtained in this study. [ABSTRACT FROM AUTHOR]

Chinese Baijiu is one of the six major distilled spirits in the world, occupying an important place in the global spirits industry due to its unique brewing technology, special taste and flavour. Historically, Baijiu has evolved into twelve flavour types, among which the Moutai‐flavour, Luzhou‐flavour, and Light‐flavour are the main types consumed in China. However, the profiles of the three flavour types of Baijiu have not been summarised and considered systematically. Here, we review the characteristics of the three main flavour types of Baijiu and discuss the key flavour components (description, odour threshold, and odour activity value), together with research advancements. Furthermore, areas where further research in Chinese Baijiu flavour is required are discussed. © 2021 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

2′-Carbonyl 5-S-acetyl-C-glycofuranosides and 2′-carbonyl 4-S-acetyl-C-glycopyranosides were converted in good yields to respective 5-thio-C-glycopyranosides and 4-thio-C-glycofuranosides under base treatment. The transformation was resulted from β-elimination on 2′-carbonyl C-glycoside to form α,β-conjugated aldehyde (or ketone) and following intramolecular hetero-Michael addition by the thiol group. [Copyright &y& Elsevier]

Bacillus subtilis is a well-characterized Gram-positive bacterium and a valuable host for recombinant protein production because of its efficient secretion ability, high yield, and non-toxicity. Here, we comprehensively review the recent studies on recombinant protein production in B. subtilis to update and supplement other previous reviews. We have focused on several aspects, including optimization of B. subtilis strains, enhancement and regulation of expression, improvement of secretion level, surface display of proteins, and fermentation optimization. Among them, optimization of B. subtilis strains mainly involves undirected chemical/physical mutagenesis and selection and genetic manipulation; enhancement and regulation of expression comprises autonomous plasmid and integrated expression, promoter regulation and engineering, and fine-tuning gene expression based on proteases and molecular chaperones; improvement of secretion level predominantly involves secretion pathway and signal peptide screening and optimization; surface display of proteins includes surface display of proteins on spores or vegetative cells; and fermentation optimization incorporates medium optimization, process condition optimization, and feeding strategy optimization. Furthermore, we propose some novel methods and future challenges for recombinant protein production in B. subtilis. Key points • A comprehensive review on recombinant protein production in Bacillus subtilis. • Novel techniques facilitate recombinant protein expression and secretion. • Surface display of proteins has significant potential for different applications. [ABSTRACT FROM AUTHOR]

Methylenetetrahydrofolate reductase (MTHFR), a folate-dependent enzyme, is reportedly involved in several cancer types. The MTHFR C677T polymorphism influences many biological processes, including tumorigenesis. However, the association between the MTHFR C677T polymorphism and breast cancer (BC) subtypes is not fully understood. In this study, the MTHFR C677T polymorphism was genotyped in 490 individuals with or without BC from southwestern China. Analysis of the association between the MTHFR C677T polymorphism and BC revealed that there was a significant association between the MTHFR C677T polymorphism and triple-negative breast cancer (TNBC) (OR = 2.83, 95% CI: 1.12–9.51, P = 0.0401). Furthermore, the MTHFR C677T polymorphism can also serve as a protective factor in luminal A breast cancer (OR = 0.57, 95% CI: 0.34–0.94, P = 0.0258). Evaluation of the association between the MTHFR C677T polymorphism and clinical characteristics indicated that people who suffered from hypertension had an increased risk for BC (OR = 2.27; 95% CI: 1.08–4.6; P = 0.0264), especially TNBC (OR = 215.38; 95% CI: 2.45–84430.3; P = 0.0317). Our results suggest that the MTHFR C677T polymorphism is significantly associated with susceptibility to luminal B breast cancer and TNBC. [ABSTRACT FROM AUTHOR]

The quantum quench dynamics of the one-dimensional Ising model in transverse field is investigated using the quantum renormalisation group method. The analytic expression of concurrence C(t) is obtained, where the initial state is a superposition state which is constructed from the eigenstates of pure Ising system. The effect of parameter a in the period and range of concurrence are exhibited respectively in the vicinity of the critical point, which show scaling behaviour. When effective magnetic field g is big enough, the maximum limit value is 1.0. However, the minimum value is different, which is also dependent on the evolved time t. [ABSTRACT FROM AUTHOR]

Human bocavirus 1 (HBoV1) infects well-differentiated (polarized) human airway epithelium (HAE) cultured at an air-liquid interface (ALI). In the present study, we applied next-generation RNA sequencing to investigate the genome-wide transcription profile of HBoV1, including viral mRNA and small RNA transcripts, in HBoV1-infected HAE cells. We identified novel transcription start and termination sites and confirmed the previously identified splicing events. Importantly, an additional proximal polyadenylation site (pA)p2 and a new distal polyadenylation site (pA)dREH lying on the right-hand hairpin (REH) of the HBoV1 genome were identified in processing viral pre-mRNA. Of note, all viral nonstructural proteins-encoding mRNA transcripts use both the proximal polyadenylation sites [(pA)p1 and (pA)p2] and distal polyadenylation sites [(pA)d1 and (pA)dREH] for termination. However, capsid proteins-encoding transcripts only use the distal polyadenylation sites. While the (pA)p1 and (pA)p2 sites were utilized at roughly equal efficiency for proximal polyadenylation of HBoV1 mRNA transcripts, the (pA)d1 site was more preferred for distal polyadenylation. Additionally, small RNA-seq analysis confirmed there is only one viral noncoding RNA (BocaSR) transcribed from nt 5199–5340 of the HBoV1 genome. Thus, our study provides a systematic and unbiased transcription profile, including both mRNA and small RNA transcripts, of HBoV1 in HBoV1-infected HAE-ALI cultures. [ABSTRACT FROM AUTHOR]

Mitochondria autophagy, termed as mitophagy, is a mechanism of specific autophagic elimination of mitochondria. Mitophagy controls the quality and the number of mitochondria, eliminating dysfunctional or excessive mitochondria that can generate reactive oxygen species (ROS) and cause cell death. Mitochondria are centrally implicated in neuron and tissue injury after stroke, due to the function of supplying adenosine triphosphate (ATP) to the tissue, regulating oxidative metabolism during the pathologic process, and contribution to apoptotic cell death after stroke. As a catabolic mechanism, mitophagy links numbers of a complex network of mitochondria, and affects mitochondrial dynamic process, fusion and fission, reducing mitochondrial production of ROS, mediated by the mitochondrial permeability transition pore (MPTP). The precise nature of mitophagy's involvement in stroke, and its underlying molecular mechanisms, have yet to be fully clarified. This review aims to provide a comprehensive overview of the integration of mitochondria with mitophagy, also to introduce and discuss recent advances in the understanding of the potential role, and possible signaling pathway, of mitophagy in the pathological processes of both hemorrhagic and ischemic stroke. The author also provides evidence to explain the dual role of mitophagy in stroke. [ABSTRACT FROM AUTHOR]

Hydrogels containing a large amount of water are widely used as fire‐resistant materials. However, when exposed to fire, the organic polymer network of gel will burn in a short time as the contained water evaporates. For that, the fire‐retarding ammonium polyphosphate (APP) and woven basalt fibers are introduced in polyacrylamide (PAAm) hydrogels to improve the fire‐resistant performance. Thermo‐gravimetric tests indicating that the APP can prevent gel from decomposition effectively when the content is larger than 13 wt%. And the APP can form a foam layer on gel surface to protect it from burning. The basalt fibers are capable of absorbing heat and strengthening the gel. With the synergetic of APP and basalt fibers, the resultant basalt/PAAm‐APP composite with high mechanical strength exhibits excellent fire‐resistant performance. It can sustain the 1300 °C flame for as long as 15 min. [ABSTRACT FROM AUTHOR]

Purpose: In intensity‐modulated proton therapy (IMPT), unaccounted‐for variation in biological effectiveness contributes to the discrepancy between the constant relative biological effectiveness (RBE) model prediction and experimental observation. It is desirable to incorporate biological doses in treatment planning to improve modeling accuracy and consequently achieve a higher therapeutic ratio. This study addresses this demand by developing a method to incorporate linear energy transfer (LET) into beam orientation optimization (BOO). Methods: Instead of RBE‐weighted dose, this LET weighted BOO (LETwBOO) framework uses the dose and LET product (LET × D) as the biological surrogate. The problem is formulated with a physical dose fidelity term, a LET × D constraint term, and a group sparsity term. The LET × D of organs at risks is penalized for minimizing the biological effect while maintaining the physical dose objectives. Group sparsity is used to reduce the number of active beams from 600–800 non‐coplanar candidate beams to between 2 and 4. This LETwBOO method was tested on three skull base tumor (SBT) patients and three bilateral head‐and‐neck (H&N) patients. The LETwBOO plans were compared with IMPT plans using manually selected beams with only physical dose constraint (MAN) and the initial MAN plan reoptimized with additional LET × D constraint (LETwMAN). Results: The LETwBOO plans show superior physical dose and LET × D sparing. On average, the [mean, maximal] doses of organs at risks (OARs) in LETwBOO are reduced by [2.85, 4.6] GyRBE from the MAN plans in the SBT cases and reduced by [0.9, 2.5] GyRBE in the H&N cases, while LETwMAN is comparable to MAN. cLET × Ds of PTVs are comparable in LETwBOO and LETwMAN, where c is a scaling factor of 0.04 μm/keV. On average, in the SBT cases, LETwBOO reduces the OAR [mean, maximal] cLET × D by [1.1, 2.9] Gy from the MAN plans, compared to the reduction by LETwMAN from MAN of [0.7, 1.7] Gy. In the H&N cases, LETwBOO reduces the OAR [mean, maximal] cLET × D by [0.8, 2.6] Gy from the MAN plans, compared to the reduction by LETwMAN from MAN of [0.3, 1.2] Gy. Conclusion: We developed a novel LET weighted BOO method for IMPT to generate plans with improved physical and biological OAR sparing compared with the plans unaccounted for biological effects from BOO. [ABSTRACT FROM AUTHOR]

Diabetes nephropathy (DN) is the leading cause of end-stage renal disease (ESRD) worldwide, and podocyte injury is the central contributor to the progression of DN. Despite the emerging evidence that has established the importance of podocyte endoplasmic reticulum (ER) stress in the pathogenesis of DN, abnormal protein O-GlcNAcylation is also augmented. Currently, the mechanism associating these two hyperglycemia-induced disorders remains poorly understood. This study intended to elucidate whether ER stress drives hyper-protein O-GlcNAcylation to cause podocyte injury in DN. We used both type 1 and type 2 DN models to confirm the occurrence of ER stress and excessive protein O-GlcNAcylation, and then podocyte purification was also conducted for further investigation. Nephroseq V5 data were mined and in vitro studies were applied to reveal the involvement of ER stress and hyper-O-GlcNAcylation in podocyte injury. Our results indicated that ER stress was induced in both type 1 and type 2 DN, and the human RNA-seq data from Nephroseq V5 showed that O-GlcNAcylation-related genes were significantly upregulated in the DN patients. We further demonstrated that ER stress occurred prior to hyper-O-GlcNAc modification and that pharmacologically inhibited protein O-GlcNAcylation can help decrease the podocyte apoptosis induced by hyperglycemia. Together, these discoveries will aid in uncovering the activation of the ER stress–O-GlcNAcylation axis in podocyte injury under DN, which will help open up new therapeutic approaches for preventing DN progression. [ABSTRACT FROM AUTHOR]

This paper reports a series of experimental studies to compare the influences of different moisture and temperature histories on the resilient modulus (MR) of a compacted clay. Parallel specimens that were compacted at the optimum moisture content (wopt) were equilibrated to six different moisture contents (w) and subjected to different numbers of freeze–thaw cycles (NFT = 0, 1, 3, 10) before determining the MR and the unconfined compressive strength (UCS). Specimens were brought to each testing condition (i.e. the combination of w and NFT) through two or three different interlaced wetting-drying and freeze–thaw processes. Such a procedure imposed different moisture and temperature histories on the specimens. Experimental results demonstrated that different moisture and temperature histories only result in noticeable differences in the MR for specimens tested at the dry side of the wopt and NFT = 1. The differences become negligible at all w levels after freeze–thaw effects have stabilised at NFT = 10. Different Moisture and temperature histories do not differentiate the relationships of the MR and UCS to the w and NFT. Meanwhile, the relationships of the MR to the UCS are unique and linear regardless of the different moisture and temperature histories. [ABSTRACT FROM AUTHOR]