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Exopolysaccharides (EPSs), which are produced by lactic acid bacteria, have been found to improve the texture and functionality of fermented dairy products. In a previous study, four nitrogen sources were identified as affecting the yield, molecular weight and structure of EPSs produced by Streptococcus thermophilus IMAU20561 in M17 medium. In this genomic and transcriptomics study, a novel eps gene cluster responsible for assembly of repeating units of EPS is reported. This eps cluster (22.3 kb), consisting of 24 open reading frames, is located in the chromosomal DNA. To explore the biosynthetic mechanisms in EPS, we completed RNA-seq analysis of S. thermophilus IMAU20561 grown in four different nitrogen sources for 5 h (log phase) or 10 h (stationary phase). GO functional annotation showed that there was a significant enrichment of differentially expressed genes (DEGs) involved in: amino acid biosynthesis and metabolism; ribonucleotide biosynthesis and metabolism; IMP biosynthesis and metabolism; and phosphorus metabolism. KEGG functional annotation also indicated enrichment of DEGs involved in amino acid biosynthesis, glycolysis, phosphotransferase system, fructose, and mannose metabolism. Our findings provide a better understanding the genetic traits of S. thermophilus, the biosynthetic pathways needed for the production of EPS, and a theoretical basis for screening dairy starter cultures. [ABSTRACT FROM AUTHOR]

Background Drug-coated balloon (DCB) angioplasty has been studied for reducing the occurrence of restenosis after treatment for intracranial atherosclerotic stenosis (ICAS), but no comparison has been published of the use of drug-coated and non-coated balloons in angioplasty for ICAS. We aim to compare the safety and efficacy of DCB angioplasty with conventional balloon (CB) angioplasty for the treatment of symptomatic ICAS. Methods One hundred cases with symptomatic ICAS treated with DCB (n=49) and CB (n=51) angioplasty were retrospectively analyzed. 1:1 propensity score matching (PSM) was completed to eliminate bias in the patients selected for further analysis. The periprocedural events and follow-up outcomes between the two groups were compared. Results There were 32 cases in each group after PSM. Technical success (<50% residual stenosis) was achieved in 30 cases (93.8%) in the DCB group and in 28 cases (87.5%) in the CB group. The rates of stroke or mortality within 30 days were 3.1% in the DCB group and 6.3% in the CB group (p=1). The incidence of restenosis in the DCB group (6.3%) was significantly lower than that in the CB group (31.3%) (p=0.01). Conclusions Compared with CB angioplasty, DCB angioplasty can effectively reduce the incidence of restenosis. Further studies are needed to validate the role of DCB angioplasty in the management of symptomatic ICAS. [ABSTRACT FROM AUTHOR]

Background: Upper tract urothelial carcinoma (UTUC) is a rare malignancy. The management of metastatic or unresectable UTUC is mainly based on evidence extrapolated from histologically homologous bladder cancer, including platinum-based chemotherapy and immune checkpoint inhibitor alone, whereas UTUC exhibits more invasiveness, worse prognosis, and comparatively inferior response to treatments. First-line immunochemotherapy regimens have been attempted in clinical trials for unselected naïve-treated cases, but their efficacies relative to standard chemo- or immuno-monotherapy still remain controversial. Here, we present a case of highly aggressive UTUC for whom comprehensive genetic and phenotypic signatures predicted sustained complete response to first-line immunochemotherapy. Case presentation: A 50-year-old man received retroperitoneoscopic nephroureterectomy and regional lymphadenectomy for high-risk locally advanced UTUC. Postoperatively, he developed rapid progression of residual unresectable metastatic lymph nodes. Pathologic analysis and next-generation sequencing classified the tumor as highly aggressive TP53/MDM2-mutated subtype with features more than expression of programmed death ligand-1, including ERBB2 mutations, luminal immune-infiltrated contexture, and non-mesenchymal state. Immunochemotherapy combining gemcitabine, carboplatin, and off-label programmed death-1 inhibitor sintilimab was initiated, and sintilimab monotherapy was maintained up to 1 year. Retroperitoneal lymphatic metastases gradually regressed to complete response. Blood-based analyses were performed longitudinally for serum tumor markers, inflammatory parameters, peripheral immune cells, and circulating tumor DNA (ctDNA) profiling. The ctDNA kinetics of tumor mutation burden and mean variant allele frequency accurately predicted postoperative progression and sustained response to the following immunochemotherapy, which were mirrored by dynamic changes in abundances of ctDNA mutations from UTUC-typical variant genes. The patient remained free of recurrence or metastasis as of this publishing, over 2 years after the initial surgical treatment. Conclusion: Immunochemotherapy may be a promising first-line option for advanced or metastatic UTUC selected with specific genomic or phenotypic signatures, and blood-based analyses incorporating ctDNA profiling provide precise longitudinal monitoring. [ABSTRACT FROM AUTHOR]

Submergence-tolerant trees are essential for vegetation restoration of the hydro-fluctuation zone of the Three Gorges Dam Reservoir (TGDR) area. Thus, it is of great significance to select the submergence-tolerant plant species by conducting in situ studies. To restore degraded riparian vegetation under the circumstances of dynamic impoundment of the TGDR, Salix matsudana Koidz., a flooding-tolerant native tree species, was introduced to conduct an in situ practical study to test its performance in re-vegetating and restoring the hydro-fluctuation zone of the TGDR. Effects of periodic moderate submergence (MS) and deep submergence (DS) on photosynthesis and growth of Salix matsudana Koidz. were investigated after three water cycles compared to a control (i.e., shallow submergence, abbreviated as SS) in order to specifically assess its application prospects in vegetation restoration under such extreme environment. Results showed that net photosynthetic rate (Pn), intrinsic water use efficiency (WUEi) and limiting value of stomata (Ls) of S. matsudana were significantly reduced in DS. However, pigment content had no significant change in all submergence treatments. Diameter at breast height (DBH) and tree height of S. matsudana were significantly decreased in both MS and DS when compared to that of SS, respectively. In contrast, the primary branch number of S. matsudana was significantly increased as submergence increased. In addition, relative diameter and height growth rates of S. matsudana were also reduced under submergence. Considering the sustained growth of this species, S. matsudana saplings are tolerant to long-term periodic submergence and can be applied to the vegetative restoration of the hydro-fluctuation zone of the TGDR region. [ABSTRACT FROM AUTHOR]

In the field of uncertainty quantification (UQ), propagation of uncertainty is one of the most important tasks, as it is essential to almost all UQ analysis. While many numerical methods have been developed for uncertainty propagation in probabilistic framework, much less has been discussed in the nonprobabilistic framework, which is important whenever one does not possess sufficient data or knowledge of the underlying systems. In this paper, we focus on the use of fuzzy sets to model uncertainty and their propagation through physical systems. In particular, we develop a numerical strategy that can efficiently propagate fuzzy sets in complex systems. The method utilizes an accurate approximation model for the solution over the support of the input fuzzy sets and then retrieves the output fuzzy set information via the approximation model. By doing so the method becomes highly efficient, as the only simulation cost is in the construction of the approximation model. In particular, we discuss the use of orthogonal polynomials for the approximation model. This is very similar to the probabilistic method of generalized polynomial chaos. However, no probability is assumed and the method remains nonprobabilistic. We prove that the fuzzy sets propagated by the approximation model can be accurate and establish the convergence via a new distance measure between fuzzy sets. Several numerical examples are provided to demonstrate the effectiveness of the method and verify the convergence analysis. [ABSTRACT FROM AUTHOR]

We establish a master-slave oligopoly game model with an upstream monopoly whose output is considered and two downstream oligopolies whose prices are considered. The existence and the local stable region of the Nash equilibrium point are investigated. The complex dynamic properties, such as bifurcation and chaos, are analyzed using bifurcation diagrams, the largest Lyapunov exponent diagrams, and the strange attractor graph. We further analyze the long-run average profit of the three firms and find that they are all optimal in the stable region. In addition, delay feedback control method and limiter control method are used in nondelayed model to control chaos. Furthermore, a delayed master-slave oligopoly game model is considered, and the three firms' profit in various conditions is analyzed. We find that suitable delayed parameters are important for eliminating chaos and maximizing the profit of the players. [ABSTRACT FROM AUTHOR]

To examine the relationship between physical appearance concern and psychological distress in female adolescent patients with systemic lupus erythematosus (SLE) was the aim of this study. A total of 84 adolescent SLE female patients and 80 age-matching healthy adolescents were evaluated for levels of appearance concern and a range of illness-specific measures to determine how these demographic and clinical variables were related to the dependent variable psychological distress. The Systemic Lupus Erythematosus Disease Activity Index was used to assess disease activity. Assessment of depression was conducted through the children depression inventory (CDI). Appearance concern was measured using the Self-Perception Profile for Children. The total CDI was 18.5 ± 4.3, indicating that these patients had more depressive symptoms, comparing with age- and sex-matched healthy controls. Furthermore, a total of 32 (38.1 %) patients had CDI larger than 19 points, indicating that they have relatively higher risk in developing depression. The CDI in control group was significantly lower than that in the SLE group (11.4 ± 1.7 vs. 18.5 ± 4.3, t = 9.93, p < 0.05). Using correlation and multiple regression analyses, we found that both appearance concern and age were predictive of depression in patients with SLE, and the former was highly correlated. This indicates that appearance concern may be associated with depression in female adolescent SLE patients. The results suggest that appearance concern is strongly associated with depression in female adolescent patients with SLE and should be routinely assessed. [ABSTRACT FROM AUTHOR]

The Quantitative Analysis of Normal Tissue Effects in the Clinic (QUANTEC) reviews summarize the currently available three-dimensional dose/volume/outcome data from multi-institutions and numerous articles to update and refine the normal tissue dose/volume tolerance guidelines. As pointed out in the review, the data have limitations and even some inconsistency. However, with the help of new physical and statistical techniques, the information in the review could be updated so that patient care can be continually improved. The purpose of this work is to demonstrate the application of a mathematical theory, the Dempster-Shafer theory, in dose/volume/outcome data analysis. We applied this theory to the original data obtained from published clinical studies describing dose response for radiation pneumonitis. Belief and plausibility concepts were introduced for dose response evaluation. We were also able to consider the uncertainty and inconsistency of the data from these studies with Yager's combination rule, a special methodology of Dempster-Shafer theory, to fuse the data at several specific doses. The values of belief and plausibility functions were obtained at the corresponding doses. Then we applied the Lyman-Kutcher-Burman (LKB) model to fit these values and a belief-plausibility range was obtained. This range could be considered as a probability range to assist physicians and treatment planners in determining acceptable dose-volume constraints. Finally, the parameters obtained from the LKB model fitting were compared with those in Emami and Burman's papers and those from other frequentist statistics methods. We found that Emami and Burman's parameters are within the belief-plausibility range we calculated by the Dempster-Shafer theory. [ABSTRACT FROM AUTHOR]

Ba0.6Sr0.4TiO3-Mg2SiO4-MgO composite ceramics were prepared by a solid-state reaction method and their dielectric tunable characteristics were investigated for the potential application as microwave tunable materials. The addition of Mg2SiO4-MgO into Ba0.6Sr0.4TiO3 forms ferroelectric (Ba0.6Sr0.4TiO3)-dielectric (Mg2SiO4-MgO) composites and shifts the Curie temperature to a lower temperature. The dielectric constant and loss tangent of Ba0.6Sr0.4TiO3-Mg2SiO4- MgO composites have been decreased and the overall tunability is maintained at a sufficiently high level. The microwave dielectric properties of Ba0.6Sr0.4TiO3-Mg2SiO4-MgO composites were evaluated. Ba0.6Sr0.4TiO3-Mg2SiO4-MgO composites have tunability of 9.2 to 10.5% at 100 kHz under 2 kV/mm, indicating that it is a promising candidate material for tunable microwave applications requiring a low dielectric constant. [ABSTRACT FROM AUTHOR]

Ba0.6Sr0.4TiO3-La(B0.5Ti0.5)O3 (B = Mg, Zn) ceramics were prepared by a solid-state reaction method, and their microwave dielectric characteristics and tunability were investigated. The ferroelectric-dielectric solid solutions with cubic perovskite structures were obtained for compositions of 10 to 60 mol% La(Mg0.5Ti0.5)O3 and 10 to 50 mol% La(Zn0.5Ti0.5)O3. With the increase of linear oxide dielectric content, the dielectric constant and tunability were decreased and Qf was increased. Ba0.6Sr0.4TiO3-La(Mg0.5Ti0.5)O3 has better dielectric properties than Ba0.6Sr0.4TiO3-La(Zn0.5Ti0.5)O3. 0.9Ba0.6Sr0.4TiO3-0.1La(Mg0.5Ti0.5)O3 has a dielectric constant ϵ = 338.2, Qf = 979 GHz and a tunability of was 3.7% at 100 kHz under 1.67 kV/mm. The Qf value of 0.5Ba0.6Sr0.4TiO3- 0.5La(Mg0.5Ti0.5)O3 reached 9367 GHz, but the tunable properties were lost. [ABSTRACT FROM AUTHOR]

Ba0.6Sr0.4TiO3-Sr(Ga0.5Ta0.5)O3 solid solutions are prepared by a solid-state reaction method, and their dielectric and tunable characteristics are investigated. The solid solutions with cubic perovskite structures are obtained for compositions of 10-50 mol% Sr(Ga0.5Ta0.5)O3. It is observed that the addition of Sr(Ga0.5Ta0.5)O3 into Ba0.6Sr0.4TiO3 causes a shift in the phase transition peak to a lower temperature. Ba0.6Sr0.4TiO3-Sr(Ga0.5Ta0.5)O3 solid solutions exhibit depressed and broadened phase transition peaks, resulting in decreased dielectric constants and dielectric losses at room temperature. With the increase of Sr(Ga0.5Ta0.5)O3 content, the dielectric constant, loss tangent, and tunability are decreased. 0.9Ba0.6Sr0.4TiO3-0.1Sr(Ga0.5Ta0.5)03 has a dielectric constant ϵ = 534 and a tunability of 16% at 100 kHz under 2.63 kV/mm. The dielectric characteristics of Ba0.6Sr0.4TiO3-Sr(Ga0.5Ta0.5) O3 ceramics at microwave frequencies are also evaluated. [ABSTRACT FROM AUTHOR]