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Aims: This study aims to investigate the specific membrane antigens that are targeted by antibodies raised against Helicobacter pylori. Methods and results: Bovine milk antibodies were prepared using whole H. pylori, purified membrane proteins, or both. Enzyme-linked immunosorbent assay and sodium dodecyl sulfate–polyacrylamide gel electrophoresis experiments revealed that these immunogens triggered anti-H. pylori antibody production in milk. The highest antibody titer was induced by the mixture of whole bacteria and purified membrane proteins. The antibodies induced by mixed immunogens significantly inhibited H. pylori growth in vitro and were used to identify catalase, plasminogen-binding protein A (PgbA), and PgbB via western blotting, immunoprecipitation, and two-dimensional western blotting followed by liquid chromatography with tandem mass spectrophotometry. The immunogenicity of PgbA and PgbB was verified in mice vaccinated with their B-cell epitope vaccines. Following prophylactic vaccination of C57BL/6 mice, each of the three antigens alone and their combination reduced the weight loss in mice, increased antibody titers, and relieved the inflammatory status of the gastric mucosa following H. pylori infection. Conclusions: Catalase, PgbA, and PgbB could serve as valuable membrane antigens for the development of anti-H. pylori immunotherapies. [ABSTRACT FROM AUTHOR]

Here, a multiple modes metamaterial absorber with four peaks was proposed and verified. All absorption peaks were excited by the multiple modes coupling between adjacent unit cells. By increasing the structural parameter D, absorption peaks were strengthened and shifteded to the low-frequency region. When the lattice constant P was increased, these peaks were decreased and shifteded to the high-frequency region. Similarly, when the dielectric layer thickness t3 was gradually increased, these absorption peaks were weakened. Temperature was gradually increased, these absorption peaks were gradually reduced and shifteded to the high-frequency region. The multi-mode coupling effetct between unit cells was important to the performance of the metamaterial absorber. [ABSTRACT FROM AUTHOR]

Background: Clostridioides difficile (C. difficile) is the major pathogen causing antibiotic-associated diarrhea. There are a variety of symptoms associated with C. difficile infection (CDI) in adults, including self-limiting diarrhea, pseudomembranous colitis, toxic megacolon, septic shock, and even death from the infection. However, the infant's intestine appears to be completely resistant to the effects of C. difficile toxins A and B with rare development of clinical symptoms. Case presentation: In this study, we reported a 1-month-old girl with CDI who was born with neonatal hypoglycemia and necrotizing enterocolitis. Her symptom of diarrhea occurred after extensive use of broad-spectrum antibiotics during hospitalization and was accompanied by elevated white blood cell, platelet, and C-reactive protein levels, and repeated routine stool examinations were abnormal. She was recovered by norvancomycin (an analogue of vancomycin) and probiotic treatment. The results of 16 S rRNA gene sequencing also demonstrated the recovery of intestinal microbiota with the enrichment of Firmicutes and Lactobacillus. Conclusions: Based on the literature review and this case report, clinicians should also pay attention to diarrhea caused by C. difficile in infants and young children. More strong evidence is needed to explain the true prevalence of CDI in this population and to better understand the C. difficile-associated diarrhea in infants. [ABSTRACT FROM AUTHOR]

Arginine and its metabolites play important roles in pain and analgesia. This study aimed to develop a comprehensive quantification method for amino acids and metabolites related to arginine metabolism in rat plasma by hydrophilic interaction chromatography–tandem mass spectrometry (HILIC–MS/MS). Rat plasma was diluted to reduce the matrix effect and deproteinized with acetonitrile. The analytes were separated on a Syncronis HILIC column with a gradient elution. MS analysis was performed in positive ion mode with an electrospray ionization source using multiple reaction monitoring technology. All calibration curves for the 10 analytes showed good linear regression (R 2 > 0.99). The limits of detection (LODs) were in the range of 0.9–13.4 μg/L. The established method was validated for intra-day and inter-day precisions (relative standard deviation [RSDs] < 6.21%) and accuracy (average recovery ranged from 87.34% to 100.35% with the RSD values less than 11.41%). This method was successfully applied to characterize dynamic alterations in the plasma of rats with neuropathic pain and thus provide service to explore the mechanism of action between metabolite changes and clinical disease. [ABSTRACT FROM AUTHOR]

Long noncoding RNAs (lncRNAs) are gradually being annotated as important regulators of multiple cellular processes. The goal of our study was to investigate the effects of the lncRNA small nucleolar RNA host gene 5 (SNHG5) in lung adenocarcinoma (LAD) and its underlying mechanisms. The findings revealed a substantial drop in SNHG5 expression in LAD tissues, which correlated with clinical-pathological parameters. Transcriptome sequencing analysis demonstrated that the inhibitory effect of SNHG5 was associated with cell adhesion molecules. Moreover, the expression of SNHG5 was shown to be correlated with epithelial–mesenchymal transition (EMT) markers in western blots and immunofluorescence. SNHG5 also had significant effects of antimigration and anti-invasion on LAD cells in vitro. Furthermore, the migration and invasion of A549 cells were suppressed by overexpressed SNHG5 in the EMT progress induced by transforming growth factor β1 (TGF-β1), and this might be due to the inhibition of the expression of EMT-associated transcription factors involving Snail, SLUG, and ZEB1. In LAD tissues, the expression of SNHG5 exhibited a positive association with E-cadherin protein expression but a negative correlation with N-cadherin and vimentin, according to the results of quantitative real-time PCR (qRT-PCR). In summary, the current work demonstrated that the lncRNA SNHG5 might limit cell migration and invasion of LAD cancer via decreasing the EMT process, indicating that SNHG5 might be used as a target for LAD therapeutic methods. [ABSTRACT FROM AUTHOR]

Growing reports indicate that Sprouty (SPRY) isoforms act as inhibitors or promoters in various types of cancers. And the occurrence of different cancers may be related to the abnormal expression of one of the SPRY isoforms. The identification of SPRY isoforms thus plays a particularly important role in determining which isoform's aberrant expression inhibits or promotes cancer. But their own properties, such as similarities in the structure and molecular weight, make their identification particularly difficult. In this article, we propose a novel method to identify SPRY isoforms using atomic force microscopy (AFM) by observing differential binding of different SPRY isoforms to bovine serum albumin (BSA), which can be used to distinguish SPRY isoforms at the single-molecule level. Specific binding of SPRY1 and BSA was observed by AFM. The reduction in the number of monomeric protein molecules caused by the partial depletion of these two proteins during binding is also consistent with the weakening of the monomeric protein bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). At the same time, the arrangement of the two proteins in a tightly bound complex was also observed. However, the SPRY3 isoform did not interact with BSA to cause aggregation, and the diameter and height of the two proteins did not change significantly compared to those before the reaction. In this way, with the participation of BSA, the two isoforms, SPRY1 and SPRY3, can be identified and separated using atomic force microscopy. In addition, the experimental result that the formation of the SPRY1–BSA complex can selectively reduce the concentration of SPRY1 isoforms in the environment will also contribute to future research on anticancer drugs influenced by SPRY1. [ABSTRACT FROM AUTHOR]

The leakage control in water distribution networks (WDNs) is of high concern in the water supply industry. One direct and effective way to reduce leakage is to adopt leakage detection and localization methods to guide water utilities to repair broken pipes in time. In order to achieve higher accuracy in the leakage detection process in WDN with multiple leaks, a novel multiple leak detection and localization framework (MLDLF) based on existing pressure and flow measurements is proposed. The MLDLF decomposed the problem into three substages: model calibration, leakage identification, and leakage localization. After using the calibrated hydraulic model to predict pressure values and estimate overall leakage flow in each area in the first stage, the data-driven methods, STLK, including the seasonal and trend decomposition using loess (STL decomposition) and the k -means clustering method, were performed in the identification stage to distinguish different leakage scenarios so as to determine the occurrence time of every leakage event. Finally, combined with the stepwise model–based fault diagnosis method, leakages were located gradually with high computational efficiency. A case study of applying MLDLF to the WDN of L-Town showed that 56.52% of the leakage events were successfully identified and located with the economic score reaching €264,873, indicating the robustness and good applicability of MLDLF in identifying and localizing all types of leaks under multiple leakage scenarios. [ABSTRACT FROM AUTHOR]

• The incidence of Clostridioides difficile infection is increasing in developing regions such as Asia. • Clinical diagnosis and routine monitoring of CDI in underdeveloped regions hampered by high cost of diagnostic reagents. • We found a novel target for the identification of hypervirulent Clostridioides difficile Sequence Type 1. • We developed a highly specific and sensitive primer set for simultaneous identification of hypervirulent ST1 and detection of toxin genes directly on total fecal DNA. The incidence of Clostridioides difficile infection and the prevalence of hypervirulent ST1 (BI/NAP1/027) strain are increasing, especially in developing countries. We aimed to develop a new PCR assay for the identification of hypervirulent ST1 strains and toxigenic C. difficile in stool samples. We established a quadruplex TaqMan real-time PCR (pilW _4-plex PCR) assay targeting the pilW , a ST1-specific type Ⅳ minor pilin gene, and three C. difficile genes including cdtB , tcdB , and hsp. The sensitivity and specificity of the assay was tested using 403 C. difficile isolates and 180 unformed stool sample. The results were compared with anaerobic culture-based conventional PCR method and MLST. The pilW _4-plex PCR identified toxigenic C. difficile in 333 (82.6%, 333/403) isolates with 100% sensitivity and specificity, and in 78 (43.3%, 78/180) stool samples with the sensitivity and specificity of 94.7% and 93.3%, respectively. Hypervirulent ST1 were detected in 21 strains and nine stool samples by the pilW _4-plex PCR. The pilW _4-plex PCR assay has no cross-reaction with non-toxigenic C. difficile or other bacteria. The pilW _4-plex PCR assay is an accurate and rapid method with high sensitivity and specificity for identification of ST1 and detection of toxigenic C. difficile in stool. [ABSTRACT FROM AUTHOR]

This paper numerically investigated the effects of the pitch ratio on the cavitation of a controllable pitch propeller. The geometric model of marine propellers is obtained by changing the pitch of the propeller VP1304. The computational fluid dynamics (CFD) solver STAR-CCM+ and large eddy simulation (LES) turbulent model are used to analyze marine propellers. The open water characteristics and cavitation behavior obtained by numerical simulation are in good agreement with available experimental data. Because the controllable pitch propeller always operates under high-efficiency conditions, the open water characteristic curves of four propellers with different pitch ratios are first calculated to obtain the corresponding advance coefficients at the highest efficiency point. Then the cavitation behavior at the highest efficiency points of four propellers with different pitch ratios is analyzed. As the pitch increases, the main type of cavitation gradually changes from leading edge cavitation to hub vortex cavitation. In addition, the causes of different cavitation types are analyzed from the aspects of pressure and velocity distribution. • The cavitation behavior at the highest efficiency points of four propellers with different pitch ratios is analyzed. • Efficiency and cavitation should be considered comprehensively when designing controllable pitch propellers. • A cavitation check should be carried out on the maximum pitch ratio of the designed propeller. [ABSTRACT FROM AUTHOR]

All-dielectric metasurfaces based on high refractive index material are becoming important components of optoelectronic devices. However, the achived functions are often fixed by the traditional all-dielectric metasurfaces due to the resonant properties are primarily excited based on the design strategies. Optically behaviors of these metasurfaces are solidified at the manufacturing stages. It is of great significance to design and verify an all-dielectric metasurface with dynamic modulation and reconfigurable properties. Here, the silicon and Ge 2 Sb 2 Te 5 (GST) blocks are combined in a hybrid arrays to achieve a dynamically modulated and reconfigurable all-dielectric metasurface. Based on the amorphous state of GST, two absorption peaks are excited by this metasurface: P1 peak (amplitude 0.87, resonance wavelength 1302 nm) and P2 peak (amplitude 0.78, resonance wavelength 2008 nm). Since the GST block is in the crystalline state, only the P1 peak (the measured amplitude is 0.71 and the resonant wavelength is 1311 nm) is obtained. This all-dielectric metasurface is highly sensitive to human body fluids (glucose solution, sweat, and urine) and ambient temperature, which can be applied in health information and temperature sensors in travel or healthy care hotel, etc. Based on optimization the crystallinity of the GST block, the dynamic modulation characteristics is achieved by this all-dielectric metasurface. The measurement results show that P2 peak is insensitive to the incidence angle of electromagnetic wave. On the contrary, with the increase of incidence angle, the P1 peak is gradually divided into two new absorption peaks (regardless of whether the GST block is in amorphous state or crystalline state). • The metamaterial can be function conversion between single/double band absorption characteristics. • Absorption peaks are sensitive to temperature(crystallinity). • Absorption peak are sensitive to environmental media. [ABSTRACT FROM AUTHOR]

The use of seawater as a substitute for pure water as supplemental moisture raises questions about its effect on the physicochemical properties of hydrochar. Therefore, this study aimed to investigate the feasibility of using seawater as supplemental moisture by comparing the physicochemical properties of products obtained through Co-hydrothermal carbonization of chicken manure and cornstalk under seawater and deionized water conditions. By varying the HTC temperature and blending ratios of CM and CS to investigate comprehensively the effect of seawater. Results indicated that the hydrochar yield experienced a variation from 54.54% to 57.40%, while the IC value changed from 7.69% to 8.46% as the ratio of CM:CS shifted from 3:1 to 1:3 under seawater conditions. The higher heating value of the hydrochars obtained under seawater conditions was lower than those obtained under deionized water conditions. This suggests that seawater conditions promote the hydrolysis reaction of organic solid waste. Furthermore, it was observed that when no lignin hydrolysis reaction occurred, seawater conditions had no discernible effect on the fuel quality of the hydrochar. However, at an HTC temperature of 250 °C, the fuel quality of the hydrochar obtained under seawater conditions was notably inferior to that of the hydrochar obtained under deionized water. Thus, an HTC temperature lower than 250 °C is necessary for the hydrothermal carbonization of organic solid waste under seawater conditions. Moreover, the relative content of surface -C-(C, H)/C C of the hydrochar obtained under seawater conditions was lower than that obtained under deionized water conditions, indicating that the hydrochar had a low degree of aromatization. Additionally, there was a significant increase in the immobilized Mg atoms in the hydrochar under seawater conditions, which affected the hydrochar yield and higher heating value of the hydrochar. This research presents a theoretical foundation for preparing solid fuels and materials using hydrothermal carbonization of saltwater as supplemental moisture. • Lignin hydrolysis occurred under seawater conditions impacted the fuel quality of the hydrochar. • The higher heating value of hydrochar reduced under seawater conditions. • The HTC temperature should control below 250 °C under seawater conditions. • Mg atoms immobilized in the hydrochar under seawater conditions was considerable. • Lignin hydrolysis occurred under seawater con ditions impacted the fuel quality of the hydrochar. [ABSTRACT FROM AUTHOR]

Background: In recent years, long non-coding RNAs (lncRNAs) are of great importance in development of different types of tumors, while the function of lncRNA ZFAS1 is rarely discussed in esophageal squamous cell carcinoma (ESCC). Therefore, we performed this study to explore the expression of exosomal lncRNA ZFAS1 and its molecular mechanism on ESCC progression. Methods: Expression of ZFAS1 and miR-124 in ESCC tissues was detected. LncRNA ZFAS1 was silenced to detect its function in the biological functions of ESCC cells. A stable donor and recipient culture model was established. Eca109 cells transfected with overexpressed and low expressed ZFAS1 plasmid and miR-124 inhibitor labeled by Cy3 were the donor cells, and then co-cultured with recipient cells to observe the transmission of Cy3-ZFAS1 between donor cells and recipient cells. The changes of cell proliferation, apoptosis, invasion, and migration in recipient cells were detected. The in vivo experiment was conducted for verifying the in vitro results. Results: LncRNA ZFAS1 was upregulated and miR-124 was down-regulated in ESCC tissues. Silencing of ZFAS1 contributed to suppressed proliferation, migration, invasion and tumor growth in vitro and induced apoptosis of ESCC cells. LncRNA ZFAS1 was considered to be a competing endogenous RNA to regulate miR-124, thereby elevating STAT3 expression. Exosomes shuttled ZFAS1 stimulated proliferation, migration and invasion of ESCC cells and restricted their apoptosis with increased STAT3 and declined miR-124. Furthermore, in vivo experiment suggested that elevated ZFAS1-exo promoted tumor growth in nude mice. Conclusion: This study highlights that exosomal ZFAS1 promotes the proliferation, migration and invasion of ESCC cells and inhibits their apoptosis by upregulating STAT3 and downregulating miR-124, thereby resulting in the development of tumorigenesis of ESCC. [ABSTRACT FROM AUTHOR]

Existing cross-sectional studies suggest a strong positive association between Internet use, physical activity, and mental health in older adults; however, longitudinal studies reporting the relationship between Internet use, physical activity, and levels of depressive symptoms in older adults are lacking. This study aimed to examine the bidirectional relationship between Internet use and depressive symptoms in older adults and its underlying mechanisms. We used two waves of follow-up data (2016 and 2018) from the China Family Panel Studies, including 5837 participants aged 60 years or above. The bidirectional relationship between Internet usage time and depressive symptoms was examined using a cross-lagged model. The mediating role of physical exercise was examined using a half-longitudinal mediation model. The results revealed a bidirectional relationship between Internet use time, frequency of physical activity, and depressive symptoms. Longer Internet use predicted lower levels of depressive symptoms, and the frequency of physical activity mediated the longitudinal relationship between Internet use and depressive symptoms in older adults. First, our study used self-report-based variables. Second, our study did not obtain the specific timing of the application of various functions of the Internet and the intensity of physical activity among older adults. Finally, based on the availability of data, our study involved only two waves of data. This may not be sufficient for a full longitudinal mediation effect test. Internet use and depressive symptoms were interrelated over time among older adults. The frequency of physical activity was a mediator of Internet use and depressive symptoms. This underscores the importance of Internet-based technologies to enable healthy living and prevent depression and loneliness in older adults. • Internet use and physical activity had a significant inhibitory effect on depressive symptoms. • Internet use, frequency of physical exercise, and depressive symptoms were bidirectional. • The frequency of physical activity mediates the association between Internet use and depressive symptoms. [ABSTRACT FROM AUTHOR]

Abstract A kinetic model of the dissolution of Al 2 O 3 into mould fluxes with low SiO 2 content was established, and the restrictive step of the dissolution process was investigated by employing a rotating cylinder method. Then, the effects of the relative moving speed between the Al 2 O 3 sample and the flux as well as the effects of the temperature and composition on the dissolution rate of Al 2 O 3 were analysed. The results showed that the dissolution of Al 2 O 3 is controlled by the diffusion in the product layer. The dissolution rate increases with the increase in the relative moving speed and temperature. The activation energy of the dissolution of Al 2 O 3 into mould fluxes A-1, A-2, and B were 150.8 kJ mol−1, 156.1 kJ mol−1, and 131.4 kJ mol−1, respectively. The dissolution accelerates with increasing (CaO+BaO)/(Al 2 O 3 +SiO 2) ratio and Na 2 O, Li 2 O, B 2 O 3 , and F− contents. The result of the analysis of the Al 2 O 3 /flux interface by scanning electron microscopy–energy dispersive X-ray spectroscopy showed that a product layer was formed in the dissolution process, with interfacial products BaO·6Al 2 O 3 and BaO·2CaO·4Al 2 O 3. [ABSTRACT FROM AUTHOR]

Clostridium difficile is the causative pathogen for antibiotic-related nosocomial diarrhea. For epidemiological study and identification of virulent clones, a new binary typing method was developed for C. difficile in this study. The usefulness of this newly developed optimized 10-loci binary typing method was compared with two widely used methods ribotyping and multilocus sequence typing (MLST) in 189 C. difficile samples. The binary typing, ribotyping and MLST typed the samples into 53 binary types (BTs), 26 ribotypes (RTs), and 33 MLST sequence types (STs), respectively. The typing ability of the binary method was better than that of either ribotyping or MLST expressed in Simpson Index (SI) at 0.937, 0.892 and 0.859, respectively. The ease of testing, portability and cost-effectiveness of the new binary typing would make it a useful typing alternative for outbreak investigations within healthcare facilities and epidemiological research. [ABSTRACT FROM AUTHOR]

The mammalian target of rapamycin ( mTOR) is a serine-threonine kinase that has been shown to be essential for the differentiation and function of various immune cells. Earlier in vitro studies showed that mTOR signalling regulates B-cell biology by supporting their activation and proliferation. However, how mTOR signalling temporally regulates in vivo germinal centre B ( GCB) cell development and differentiation into short-lived plasma cells, long-lived plasma cells and memory cells is still not well understood. In this study, we used a combined conditional/inducible knock-out system to investigate the temporal regulation of mTOR complex 1 ( mTORC1) in the GCB cell response to acute lymphocytic choriomeningitis virus infection by deleting Raptor, a main component of mTORC1, specifically in B cells in pre- and late GC phase. Early Raptor deficiency strongly inhibited GCB cell proliferation and differentiation and plasma cell differentiation. Nevertheless, late GC Raptor deficiency caused only decreases in the size of memory B cells and long-lived plasma cells through poor maintenance of GCB cells, but it did not change their differentiation. Collectively, our data revealed that mTORC1 signalling supports GCB cell responses at both early and late GC phases during viral infection but does not regulate GCB cell differentiation into memory B cells and plasma cells at the late GC stage. [ABSTRACT FROM AUTHOR]

A copper catalyzed hydrodefluorination of propargylic gem -difluorides was reported, in which two C–F bonds was reductive converted to C–H bonds and a new alkyne product was afforded with the triple bond migrating one methylene. Mechanistic studies show that the products are achieved by stepwise C–F bond reductive hydrogenation, and an allenyl monofluoride is proposed to be one of the active intermediates. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, we study the normality of families of meromorphic functions concerning shared values. We consider mainly whether a family meromorphic functions [ABSTRACT FROM AUTHOR]

Abstract: Electrokinetic (EK) remediation of pentachlorophenol (PCP)-contaminated soil is difficult because PCP dissociates at different pH values along soil column and shows different transport behaviors near anode and cathode. In the present study, a permeable reactive barrier (PRB) filled with reactive Pd/Fe particles was installed between anode and cathode to reach the dechlorination of PCP during its EK movement. When PRB was installed at the position of 0.3 (normalized distance from anode), PCP in the section from anode to PRB could transport through PRB, while PCP in the section from cathode to PRB was accumulated near PRB. PCP was hardly dechlorinated by PRB wherein high pH was reached. When PRB was installed at the position of 0.5 and the pH in the PRB was decreased by periodical injection of HAc, 49% of PCP was removed, and 22.9% was recovered as phenol which was mostly collected in catholyte. The mechanism of PCP removal was proposed as the EK movement of PCP into the PRB compartment, the complete dechlorination of PCP to phenol by Pd/Fe in the PRB compartment, and the subsequent removal of phenol by electroosmosis. This study proved that the combination of electrokinetics and Pd/Fe PRB was effective for the remediation of PCP-contaminated soil. [Copyright &y& Elsevier]

Abstract: Treatment of soils contaminated with chlorinated hydrophobic organic compounds (CHOCs) remains a challenge for environmental scientists worldwide. In this study surfactant-enhanced electrokinetics (SEEK) was coupled with permeable reactive barrier (PRB) composed of microscale Pd/Fe to treat a hexachlorobenzene (HCB)-contaminated soil. A nonionic surfactant, Triton X-100 (TX-100), was selected as the solubility-enhancing agent. Five bench-scale tests were conducted to investigate the performance of EK–PRB on HCB removal from soils. Results showed that the HCB removal was generally increased by a factor of 4 by EK coupled with PRB compared with EK alone (60% versus 13%). In the EK–PRB system, HCB was removed from soil through several sequential processes: the movement driven by electroosmotic flow (EOF) in the anode column, the complete adsorption/degradation by the reactive Pd/Fe particles in PRB, and the consequent movement by EOF and probable electrochemical reactions in the cathode column. TX-100 was supposed to be a superior enhancement agent for HCB removal, not only in the EOF movement process but also in the Pd/Fe degradation process. This study indicates that the combination of SEEK and Pd/Fe PRB is efficient and promising to remove CHOCs from contaminated soils. [ABSTRACT FROM AUTHOR]

Abstract: The electromechanical coupled dynamic model of the stator of the bar-type ultrasonic motor is derived based on the finite element method. The dynamical behavior of the stator is analyzed via this model and the theoretical result agrees with the experimental result of the stator of the prototype motor very well. Both the structural design principles and the approaches to meet the requirements for the mode of the stator are discussed. Based on the pattern search algorithm, an optimal model to meet the design requirements is established. The numerical simulation results show that this optimal model is effective for the structural design of the stator. [Copyright &y& Elsevier]

Abstract: A cylinder type 3-DOF ultrasonic motor consists of a cylinder-shaped stator and a spherical rotor. Two bending vibration modes with orthogonality and a longitudinal vibration mode are excited in the stator by three groups of piezoelectric ceramic elements, respectively. The combinations of any two modes mentioned above push the rotor to rotate in one plane. Totally, the rotor can rotate around x, y or z-axes. This paper summarizes some key issues in developing the motor whose output properties and efficiency can be improved. These key issues include selection of the vibration modes, consistency of the modal frequencies, placement of the piezoelectric ceramic elements and the supporting plane, setting of pre-pressure and rotor–stator contact angle, influence of interfering modes. [Copyright &y& Elsevier]

Abstract: This paper introduces an optimization design method for a three-degree of freedom (three-DOF) ultrasonic motor stator using constrained variable metric algorithm (CVMA). It is a circular cylindrical stator with a spherical rotor attached at its end. A mathematical model of the stator is established with combining the finite element method (FEM) and the optimal analysis method. Based on the model, the authors code an optimal program, which is implemented with MATLAB. The object is to optimize the characteristic length L 1, and L 2 of the stator in order to satisfy its vibration and contained conditions. According the optimization results, the stator is manufactured and tested. The experiments show that the stator''s mode frequencies and shapes agree well with those predicted by the program. The program is easy to operate, and that is time saving. [Copyright &y& Elsevier]

In this work, the antioxidant components in persimmon (Diospyros kaki) leaves were separated by offline two‐dimensional liquid chromatography‐electrochemical detection (LC×LC‐ECD) and identified by LC‐tandem mass spectrometry (LC‐MS/MS). A total of 33 antioxidants, mainly proanthocyanidins, and glycosides of kaempferol and quercetin, were identified. The antioxidant assays demonstrated that the fractions collected from the first‐dimension LC (1D‐LC) possessed considerable radical scavenging capabilities, with correlation coefficients of peak area versus radical scavenging capability of 1,1‐diphenyl‐2‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) being 0.9335 and 0.9116, respectively. The fingerprinting showed that 37 peaks were present in all samples. The major antioxidant components of persimmon leaves were the glycosides of kaempferol and quercetin. Finally, fourteen antioxidants were quantitatively assessed. Offline LC×LC provided high peak capacity and separation; ECD enabled specific screening and detection of antioxidant components; and MS/MS provided excellent identification capability. In this study, the combination of the three approaches was utilized to screen for antioxidant components in persimmon leaves, with satisfactory findings. In conclusion, this technique is an effective means for rapid analysis of antioxidant components and quality control of medicinal plants, achieving rapid separation of congeners and facilitating more accurate qualitative and quantitative analyses. [ABSTRACT FROM AUTHOR]

Pyracantha fortuneana (P. fortuneana) fruit is a wild fruit that is popular because of its delicious taste and numerous nutrients, and phenolic compounds are considered to be the main bioactive components in P. fortuneana fruits. However, the relationship between phenolic compounds and their antioxidant and tyrosinase (TYR) inhibitory activities during the ripening process is still unclear. The study compared the influence of the five developmental stages on the accumulation of phenolic compounds, antioxidant activity, and TYR inhibitory activity in the fruits of P. fortuneana. The compounds were identified by offline two‐dimensional liquid chromatography‐electrochemical detection (2D‐LC‐ECD) combined with liquid chromatography–tandem mass spectrometry, and the main active ingredients were quantified. The results showed that stage II had higher total phenolic and flavonoid content, as well as higher antioxidant and TYR inhibitory activity, but the total anthocyanin content was lowest at this stage. A total of 30 compounds were identified by 2D‐LC‐ECD. Orthogonal partial least squares discriminant analysis screened out six major potential markers, including phenolic acids, procyanidins, and flavonoids. In addition, it was found that caffeoylquinic acids, procyanidins, and flavonoids were higher in stage II than in stages I, III, IV, and V, whereas anthocyanins accumulated gradually from stages III to V. Therefore, this study suggests that the changes in antioxidant and TYR inhibitory activities of P. fortuneana during the five developmental stages may be due to the transformation of procyanidins, caffeoylquinic acids, and phenolic glycosides into other forms during the fruit maturation process. Practical Application: Differences in chemical constituents, antioxidant, and tyrosinase inhibitory activities in fruit maturity stages of P. fortuneana were elucidated to provide reference for rational harvesting and utilization of the fruits and their bioactive components. These findings are expected to provide a comprehensive assessment of the bioactive profile and guide the food industrial production. [ABSTRACT FROM AUTHOR]

AbstractThe Aesthetics Scale is one of the most commonly used aesthetics evaluation scale in HCI. In this study, a Chinese version of the Aesthetics Scale (C-AS) was translated and validated using the forward–backward translation method. The C-AS passed the content validity and face validity tests. We then recruited 310 Chinese users and tested the psychological properties of the C-AS using the China Railway Customer Service Center ticketing platform as the test material. The experimental results showed that the C-AS has high reliability, validity, and sensitivity. Following rigorous testing, the results of this work may provide Chinese UX practitioners with a standardized aesthetics scale that researchers and practitioners can use with confidence. [ABSTRACT FROM AUTHOR]

We investigate wetting behaviors of two kinds of hydrophilic ordered nanoporous anodic alumina (PAA). The water contact angle (CA) increases at first and subsequently decreases with increasing pore diameter of PAA with closed-pore structure, while the water CA decreases monotonously on PAA with open-pore structure. These interesting wetting behaviors are mainly due to the presence/absence of closed-air in the PAA. The closed-air could prevent water from entering into the nanopores. This work offers insight to control wetting by tailoring the surface nanostructure and will be significant for applications in printing, coating, etc. [ABSTRACT FROM AUTHOR]

Background: Evidence from observational studies suggests an association between chronic obstructive pulmonary disease (COPD) and lung cancer. The potential interactions between the immune system and the lungs may play a causative role in COPD and lung cancer and offer therapeutic prospects. However, the causal association and the immune-mediated mechanisms between COPD and lung cancer remain to be determined. Methods: We employed a two-sample Mendelian randomization (MR) approach to investigate the causal association between COPD and lung cancer. Additionally, we examined whether immune cell signals were causally related to lung cancer, as well as whether COPD was causally associated with immune cell signals. Furthermore, through two-step Mendelian randomization, we investigated the mediating effects of immune cell signals in the causal association between COPD and lung cancer. Leveraging publicly available genetic data, our analysis included 468,475 individuals of European ancestry with COPD, 492,803 individuals of European ancestry with lung cancer, and 731 immune cell signatures of European ancestry. Additionally, we conducted single-cell transcriptome sequencing analysis on COPD, lung cancer, and control samples to validate our findings. Findings: We found a causal association between COPD and lung cancer (odds ratio [OR] = 1.63, 95% confidence interval [CI] = 1.31–2.02, P-value < 0.001). We also observed a causal association between COPD and regulatory T cells (odds ratio [OR] = 1.19, 95% confidence interval [CI] = 1.01–1.40, P-value < 0.05), as well as a causal association between regulatory T cells and lung cancer (odds ratio [OR] = 1.02, 95% confidence interval [CI] = 1.002–1.045, P-value < 0.05). Furthermore, our two-step Mendelian randomization analysis demonstrated that COPD is associated with lung cancer through the mediation of regulatory T cells. These findings were further validated through single-cell sequencing analysis, confirming the mediating role of regulatory T cells in the association between COPD and lung cancer. Interpretation: As far as we are aware, we are the first to combine single-celled immune cell data with two-sample Mendelian randomization. Our analysis indicates a causal association between COPD and lung cancer, with regulatory T cells playing an intermediary role. [ABSTRACT FROM AUTHOR]

Summary: The coronavirus disease 2019 (COVID‐19) pandemic has a significant impact on the immune system. This is the first and largest study on pre‐existing immune thrombocytopenia (ITP) patients infected with COVID‐19 in China. We prospectively collected ITP patients infected with COVID‐19 enrolled in the National Longitudinal Cohort of Hematological Diseases (NICHE, NCT04645199) and followed up for at least 1 month after infection. One thousand and one hundred forty‐eight pre‐existing ITP patients were included. Two hundred and twelve (18.5%) patients showed a decrease in the platelet (PLT) count after infection. Forty‐seven (4.1%) patients were diagnosed with pneumonia. Risk factors for a decrease in the PLT count included baseline PLT count <50 × 109/L (OR, 1.76; 95% CI, 1.25–2.46; p = 0.001), maintenance therapy including thrombopoietin receptor agonists (TPO‐RAs) (OR, 2.27; 95% CI, 1.60–3.21; p < 0.001) and previous splenectomy (OR, 1.98; 95% CI, 1.09–3.61; p = 0.03). Risk factors for pneumonia included age ≥40 years (OR, 2.45; 95% CI, 1.12–5.33; p = 0.02), ≥2 comorbidities (OR, 3.47; 95% CI, 1.63–7.64; p = 0.001), maintenance therapy including TPO‐RAs (OR, 2.14; 95% CI, 1.17–3.91; p = 0.01) and immunosuppressants (OR, 3.05; 95% CI, 1.17–7.91; p = 0.02). In this cohort study, we described the characteristics of pre‐existing ITP patients infected with COVID‐19 and identified several factors associated with poor outcomes. [ABSTRACT FROM AUTHOR]

During continuous casting of high‐alloy (Al, Mn, Ti) steels, the operational issues and quality problems caused by interfacial reaction or peritectic features need to be solved by applying suitable mold fluxes. Intensive efforts have been made to optimize properties, and hereby, several types of mold fluxes, including mold fluxes with high basicity and high glassy property (dual‐high mold fluxes), mold fluxes with strong oxidizing components to protect SiO2 from reduction, mold fluxes with high SiO2 content to decrease the viscosity and basicity, mold fluxes with low SiO2 content for the purpose of attenuated reactivity, and molten mold fluxes to increase consumption, have been developed. Significant efforts have been made to study the theoretical basis and practical application of these mold fluxes. To summarize, the most potential solution of mold fluxes for high‐alloy (Al, Mn, Ti) steel continuous casting is to further optimize the nonreactive mold fluxes systematically to achieve a coordinated control of lubrication and heat transfer. The amount of SiO2 will be greatly reduced in mold fluxes due to the interfacial reaction when casting high Al steels with traditional CaO‐SiO2‐based mold fluxes, which deteriorates continuous casting conditions and may cause defects of slabs. The most potential solution is to develop CaO‐Al2O3‐based mold fluxes to attenuate interfacial reaction. [ABSTRACT FROM AUTHOR]

Background: Esophageal cancer is one of the most common malignant tumors in the world. With currently available therapies, only 20% ~ 30% patients can survive this disease for more than 5 years. TRAIL, a natural ligand for death receptors that can induce the apoptosis of cancer cells, has been explored as a therapeutic agent for cancers, but it has been reported that many cancer cells are resistant to TRAIL, limiting the potential clinical use of TRAIL as a cancer therapy. Meanwhile, Periplocin (CPP), a natural compound from dry root of Periploca sepium Bge, has been studied for its anti-cancer activity in a variety of cancers. It is not clear whether CPP and TRAIL can have activity on esophageal squamous cell carcinoma (ESCC) cells, or whether the combination of these two agents can have synergistic activity. Methods: We used MTS assay, flow cytometry and TUNEL assay to detect the effects of CPP alone or in combination with TRAIL on ESCC cells. The mechanism of CPP enhances the activity of TRAIL was analyzed by western blot, dual luciferase reporter gene assay and chromatin immunoprecipitation (ChIP) assay. The anti-tumor effects and the potential toxic side effects of CPP alone or in combination with TRAIL were also evaluated in vivo. Results: In our studies, we found that CPP alone or in combination with TRAIL could inhibit the proliferation of ESCC cells and induce apoptosis, and we certificated that combination of two agents exert synergized functions. For the first time, we identified FoxP3 as a key transcriptional repressor for both DR4 and DR5. By down-regulating FoxP3, CPP increases the expression of DR4/DR5 and renders ESCC cells much more sensitive to TRAIL. We also showed that CPP reduced the expression of Survivin by inhibiting the activity of Wnt/β-catenin pathway. All these contributed to synergistic activity of CPP and TRAIL on ESCC cells in vitro and in vivo. Conclusion: Our data suggest that CPP and TRAIL could be further explored as potential therapeutic approach for esophageal cancer. [ABSTRACT FROM AUTHOR]

• Antibody response to COVID-19 vaccination is largely impaired during malignancy. • Tumor-induced COVID-19 vaccine bluntness is associated with poor follicular helper T cell and B cell responses. • The tumor-suppressed COVID-19 vaccine effectiveness is restored by PD-1/PD-L1 blockade. • PD-1/PD-L1 blockade preferentially preserves follicular helper T cell response during malignancy. • The PD-1/PD-L1 blockade-recovered COVID-19 vaccine effectiveness is independent of anti-tumor therapeutic outcomes. The COVID-19 vaccinations are crucial in protecting against the global pandemic. However, accumulating studies revealed the severely blunted COVID-19 vaccine effectiveness in cancer patients. The PD-1/PD-L1 immune checkpoint blockade (ICB) therapy leads to durable therapeutic responses in a subset of cancer patients and has been approved to treat a wide spectrum of cancers in the clinic. In this regard, it is pivotal to explore the potential impact of PD-1/PD-L1 ICB therapy on COVID-19 vaccine effectiveness during ongoing malignancy. In this study, using preclinical models, we found that the tumor-suppressed COVID-19 vaccine responses are largely reverted in the setting of PD-1/PD-L1 ICB therapy. We also identified that the PD-1/PD-L1 blockade-directed restoration of COVID-19 vaccine effectiveness is irrelevant to anti-tumor therapeutic outcomes. Mechanistically, the restored COVID-19 vaccine effectiveness is entwined with the PD-1/PD-L1 blockade-driven preponderance of follicular helper T cell and germinal center responses during ongoing malignancy. Thus, our findings indicate that PD-1/PD-L1 blockade will greatly normalize the responses of cancer patients to COVID-19 vaccination, while regardless of its anti-tumor efficacies on these patients. [ABSTRACT FROM AUTHOR]

Ovomucin (OVM) is a natural glycoprotein with various biological activities but poor solubility. This study aimed to enhance the solubility of OVM by using an ultrasonic-assisted method. The effect of ultrasound (US) on the structure, thermal stability and biological functions of OVM aggregates was evaluated. It was found that insoluble OVM aggregates were dissociated and the solubility increased significantly to 90.0 % after US under 400 W for 45 min. US also improved the onset temperature (To) and denaturation temperature (Td) of OVM. More importantly, the cholesterol binding capacity of both OVM and its digestion products were significantly improved after US (p < 0.05). The gastrointestinal digestion products of US-OVM also showed higher α-amylase and α-glucosidase inhibition than native OVM aggregates. US-induced dissociation of OVM aggregates and the conversion of β-sheet and β-turn to random coil, resulting in the exposure of hydrophobic binding sites may be an important reason for the enhanced stability and adsorption capacity. These findings suggested that US was an effective method for preparing soluble OVM and improved its adsorption capacity, which can further facilitate the application of OVM in the food industry. [Display omitted] • US promoted the depolymerisation of OVM insoluble aggregates and the formation of soluble aggregates. • US improved the flow and thermal stability of OVM. • US improved the cholesterol adsorption capacity of OVM and its gastrointestinal digestion products. • The gastric and intestinal digestion products of US-OVM had the potential to control blood glucose. [ABSTRACT FROM AUTHOR]

Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs), especially the Delta and Omicron variants, have been reported to show significant resistance to approved neutralizing monoclonal antibodies (mAbs) and vaccines. We previously identified a mAb named 35B5 that harbors broad neutralization to SARS-CoV-2 VOCs. Herein, we explored the protection efficacy of a 35B5-based nasal spray against SARS-CoV-2 VOCs in a small-scale clinical trial. Methods We enrolled 30 healthy volunteers who were nasally administered the modified 35B5 formulation. At 12, 24, 48, and 72 hours after nasal spray, the neutralization efficacy of nasal mucosal samples was assayed with pseudoviruses coated with SARS-CoV-2 spike protein of the wild-type strain or the Alpha, Beta, Delta, or Omicron variants. Results The nasal mucosal samples collected within 24 hours after nasal spray effectively neutralized SARS-CoV-2 VOCs (including Delta and Omicron). Meanwhile, the protection efficacy was 60% effective and 20% effective at 48 and 72 hours after nasal spray, respectively. Conclusions A single nasal spray of 35B5 formation conveys 24-hour effective protection against SARS-CoV-2 VOCs, including the Alpha, Beta, Delta, or Omicron variants. Thus, 35B5 nasal spray might be potential in strengthening SARS-CoV-2 prevention, especially in high-risk populations. Clinical Trials Registration 2022-005-02-KY. [ABSTRACT FROM AUTHOR]

Employing the urea oxidation reaction (UOR) instead of the water oxidation reaction can not only decrease the theoretic hydrogen generation cell voltage in sustainable energy conversion but also eliminate urea pollution in water. Herein, we used a facile in situ trapping and pre-modification strategy to synthesize MoC@C and hybrid Ni/WC@C nanoparticles and employed the two materials as hydrogen evolution reaction and UOR catalysts, respectively, in an electrolytic cell. The resultant setup can achieve a catalytic current density of 20 mA cm−2 at a cell voltage of 1.5 V in alkaline solutions and maintain stability for at least 12 h in the same conditions. [ABSTRACT FROM AUTHOR]

Papillary thyroid cancer (PTC), accounting for more than 80 percent of all cases of thyroid cancer, is a form of a cancerous tumor that has a very favorable prognosis. However, patients diagnosed with PTC who are already in an advanced state have a dismal outlook. This study aimed to establish the diagnostic relevance of PRR15 expression in PTC patients as well as its levels in PTC samples and its connection with immune infiltrates. The TCGA and GEO datasets were combed through to obtain information on PTC patients. The "Limma" program was used to screen for differentially expressed mRNAs (DEMs), and the results were displayed using volcano plots and heat maps. The Wilcoxon test was used to examine the level of PRR15 expression in PTC patients in comparison with that of normal tissues. To study the connection between the immune infiltration level and PRR15 expression in PTC, the single-sample sequence set enrichment analysis (ssGSEA) from the R package was utilized. The expression of PRR15 was analyzed with RT-PCR in PTC cells and normal cells. In order to evaluate the diagnostic significance of PRR15 expression, ROC assays were carried out. Experiments using CCK-8 were carried out to investigate the impact that PRR15 knockdown could have on the proliferation of PTC cells. In this study, 17 overlapped DEMs between PTC specimens and normal specimens were identified, including MPPED2, IPCEF1, SLC4A4, PKHD1L1, DIO1, CRABP1, TPO, TFF3, SPX, TCEAL2, ZCCHC12, SYTL5, PRR15, CHI3L1, SERPINA1, GABRB2, and CITED1. Our attention focused on PRR15 which was highly expressed in PTC specimens as compared with nontumor specimens. PRR15 had an AUC value of 0.926 (95% CI 0.902–0.950) for PTC based on TCGA datasets. Pan-cancer assays suggested PRR15 as an oncogenic gene in many types of tumors. Moreover, we found that PRR15 expression was positively correlated with eosinophils, NK cells, NK CD56bright cells, IDC, macrophages, DC, mast cells, and Th1 cells. Further investigations with CCK-8 demonstrated that inhibiting PRR15 resulted in a decrease in the proliferation of PTC cells. Overall, PRR15 was confirmed to be a biomarker for PTC patients and a predictor of response to immunotherapy. [ABSTRACT FROM AUTHOR]

The use of organic working fluids in organic Rankine cycle (ORC) systems may lead to thermal decomposition, which negatively impacts system performance and safety. In this work, a simplified theoretical method based on the transition state theory is proposed to predict the ideal maximum thermal stabilization temperature of organic working fluids. This method involves considering the initial decomposition reaction of the working fluids and calculating the total reaction rate of the initial decomposition. By setting an acceptable decomposition rate, the ideal maximum thermal stabilization temperature of the working fluid can be determined. Using this method, the total reaction rate constants of several typical hydrocarbon, hydrofluorocarbon and siloxane working fluids were obtained in the temperature range of 300∼700 K. The predicted maximum operational temperatures were in good agreement with most experimental results. The branch ratio analyses show that C–C bond cleavage contributed mainly to the decomposition of hydrocarbons, the removal of HF and C–C bond cleavage contributed mainly to that of HFCs, and the Si–C bond cleavage contributed mainly to that of siloxanes. Only considering these main reactions in the reaction rate calculation can greatly reduce calculation cost without significantly impacting the prediction accuracy. • A new method is proposed for thermal stabilization temperature prediction. • Thermal stabilization temperatures of several alkanes, hydrofluorocarbons, and siloxanes were obtained. • The main contributing reaction pathways to the initial decomposition are identified. [ABSTRACT FROM AUTHOR]

Abstract: A spectrometric method was investigated to measure the activities of recombinant human cyclic nucleotide phosphodiesterase 4 (PDE4), based on the use of malachite green (MLG) to quantify phosphate released from adenosine-5′-monophosphate (AMP) by the action of calf intestinal alkaline phosphatase (CIAP). Glycerol at 2% stabilized the complex between MLG and phosphomolybdate, whose absorbance at 630nm was proportional to phosphate concentrations with resistance to common substances in PDE4 reaction mixtures except papaverine. CIAP had the Michaelis–Menten constant (K m) of (12.0±2.1)μM (n =3) for AMP at pH 7.4, and was resistant to EDTA below 0.20mM. By the coupled end-point assay at 30.0UL−1 CIAP with reaction durations within 30min, the rates to release phosphate in PDE4 reaction mixtures containing 10.0mM MgCl2 and 0.10mM EDTA linearly responded to the amounts of PDE4 over wide ranges. Meanwhile, K m of PDE4 was (8.8±0.2)μM (n =2), zinc ion inhibited PDE4 and rolipram had the inhibition constant about 10nM. These results supported that by the coupled end-point assay, this method was promising to screen of PDE inhibitors that had no interference with the MLG assay of phosphate. [Copyright &y& Elsevier]

Abstract: The photografting of methacrylic acid (MAA) onto high-density polyethylene (HDPE) initiated by aliphatic ketones, butanone, pentanone, heptanone, etc. has been reported. When these ketones were used alone or just with ethanol, grafting did not occur. However, grafting took place when a proper butanone/water/ethanol mixed solvent was used. When the volume ratio of butanone was fixed, the grafting of MAA onto HDPE became easier with an increase in the volume ratio of water. The grafting of MAA onto HDPE became easier and faster with a decrease in the volume ratio of butanone. The grafting rate increased with the increase of monomer concentration. The nature of the alcohol also affected the self-initiation by aliphatic ketone; ethanol was found to be better than methanol. Possibly, hydrogen bond formed between aliphatic ketone and water increases the energy and lifetime of the excited state of the ketone, permitting it to act as a grafting and polymerisation initiator. FTIR characterization of the grafted samples proves the successful grafting of MAA onto HDPE. The water absorbency of the grafted samples increased almost linearly with the extent of grafting both in air and in water. The PE films grafted in the butanone/water/ethanol solvent adsorbed approximately 30–40mass% water per p-MAA. [Copyright &y& Elsevier]

Follicular regulatory T cells (Tfrs), a specialized subset of regulatory T cells (Tregs), have a particular role in the control of follicular helper T cell-driven germinal center (GC) responses. Following differentiation signals similar to those received by follicular helper T cells (Tfhs), Tfrs gain expression of characteristic chemokine receptors and transcription factors, such as CXCR5 and Bcl-6, allowing them to migrate into the B-cell follicle and perform in situ suppression. Thus, together with Tfhs, Tfrs help maintaining an optimized GC-reaction. However, the mechanism underlying the Treg-to-Tfr transition remains obscure. Here, we established a highly reproducible protocol for investigating the differentiation of Tregs into Tfrs by constructing spleen-chimeric mice combined with retrovirus transduction. We demonstrated that using this strategy, over 4 folds of Tregs could differentiate into Tfrs in Bcl-6 overexpression group compared to control counterparts (Migr1), and Bcl-6 could efficiently promote Tfr differentiation during acute viral infection. Hence, this method provides us an easy access to investigate the factors that regulate the differentiation program that converts Tregs into Tfrs, which will enhance our understanding of the networks regulating GC-reaction and shed new light on the molecular basis of immune homeostasis. [ABSTRACT FROM AUTHOR]

ABSTRACT Functions of α- and β-branch carotenoids in whole-plant acclimation to photo-oxidative stress were studied in Arabidopsis thaliana wild-type (wt) and carotenoid mutants, lutein deficient ( lut2, lut5), non- photochemical quenching1 ( npq1) and suppressor of zeaxanthin- less1 ( szl1) npq1 double mutant. Photo-oxidative stress was applied by exposing plants to sunflecks. The sunflecks caused reduction of chlorophyll content in all plants, but more severely in those having high α- to β-branch carotenoid composition ( α/ β-ratio) ( lut5, szl1npq1). While this did not alter carotenoid composition in wt or lut2, which accumulates only β-branch carotenoids, increased xanthophyll levels were found in the mutants with high α/ β-ratios ( lut5, szl1npq1) or without xanthophyll-cycle operation ( npq1, szl1npq1). The PsbS protein content increased in all sunfleck plants but lut2. These changes were accompanied by no change ( npq1, szl1npq1) or enhanced capacity (wt, lut5) of NPQ. Leaf mass per area increased in lut2, but decreased in wt and lut5 that showed increased NPQ. The sunflecks decelerated primary root growth in wt and npq1 having normal α/ β-ratios, but suppressed lateral root formation in lut5 and szl1npq1 having high α/ β-ratios. The results highlight the importance of proper regulation of the α- and β-branch carotenoid pathways for whole-plant acclimation, not only leaf photoprotection, under photo-oxidative stress. [ABSTRACT FROM AUTHOR]

To identify the common inhibition types, the putative decision system is unsatisfactory. In a new decision system, Michaelis-Menten constants and maximal reaction rates were plotted versus inhibitor concentrations for deriving Kik and Kiv as the inhibition constants, respectively; their difference was quantified as the ratio of the larger one to the smaller one. Such ratios below 2.0 suggested uncompetitive inhibitors, over 5.0 suggested noncompetitive or competitive inhibitors, and from 2.0 to 5.0 suggested mixed inhibitors. By the new decision system, (i) the simulation recovery of uncompetitive inhibitors under CVs of 2% or 5% was improved by four times, but that of competitive or noncompetitive inhibitors was improved slightly; (ii) the recovery of L-phenylalanine as an uncompetitive inhibitor of intestinal alkaline phosphatase reached 38%, while the putative decision system lost all; the recovery of xanthine as a competitive inhibitor of uricase was improved slightly. Therefore, the new decision system was better. [ABSTRACT FROM AUTHOR]

Abstract: In higher plants, regulation of excess absorbed light is essential for their survival and fitness, as it enables avoidance of a build up of singlet oxygen and other reactive oxygen species. Regulation processes (known as non-photochemical quenching; NPQ) can be monitored by steady-state fluorescence on intact plant leaves. Pulse amplitude modulated (PAM) measurements of chlorophyll a fluorescence have been used for over 20 years to evaluate the amount of NPQ and photochemistry (PC). Recently, a quantum yield representation of NPQ (Φ NPQ), which incorporates a variable fraction of open reaction centers, was proposed by Hendrickson et al. [L. Hendrickson, R.T. Furbank, W.S. Chow, Photosynth. Res. 82 (2004) 73]. In this work we extend the quantum yield approach to describe the yields of reversible energy-dependent quenching (Φ qE), state transitions to balance PC between photosystems II and I (Φ qT), and photoinhibition quenching associated with damaged reaction centers (Φ qI). We showed the additivity of the various quantum yield components of NPQ through experiments on wild-type and npq1 strains of Arabidopsis thaliana. The quantum yield approach enables comparison of Φ qE with data from a variety of techniques used to investigate the mechanism of qE. We showed that Φ qE for a series of A. thaliana genotypes scales linearly with the magnitude of zeaxanthin cation formation, suggesting that charge-transfer quenching is largely responsible for qE in plants. [Copyright &y& Elsevier]

Abstract: A new strategy was proposed to estimate the initial rates of reactions catalyzed by Michaelis–Menten enzymes via integrating the classical initial rate method for low activities with an improved integrated method for high activities. Between these two individual methods, this integration strategy required: (a) the consistent linear response slopes, acquired with an optimized preset substrate concentration (PSC) to derive the initial rates from the maximal reaction rates estimated by the improved integrated method; (b) an overlapped region of the initial rates measurable with consistent results, realized with an optimized reaction duration to record reaction curves for analyses by the improved integrated method; (c) a switch cutoff, preset as the instantaneous substrate concentration slightly above that after a given lag time when the enzyme activity was just below the upper limit for the linear response of the classical initial rates. By simulation with uricases at a given initial substrate concentration (S 0), the optimized PSC was 93% S 0, the optimized reaction duration at S 0 from 0.35-fold to 11.0-fold Michaelis–Menten constant (K m) was within 6.0min and the switch cutoff was available at the given S 0 after 30-s lag time, all of which were combined to produce 300-fold linear ranges. By experimentation with one uricase of K m at 6.6μM and the other uricase of K m at 220μM under optimized conditions, this integration strategy with S 0 at 75μM produced 100-fold linear ranges. Thus, this integration strategy exhibited much expanded linear ranges and practical efficiency over wide ratios between S 0 and K m. [Copyright &y& Elsevier]