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Generalist microbes have adapted to a multitude of environmental stresses through their integrated stress response system. Individual stress responses have been quantified by E. coli metabolism and expression (ME) models under thermal, oxidative and acid stress, respectively. However, the systematic quantification of cross-stress & cross-talk among these stress responses remains lacking. Here, we present StressME: the unified stress response model of E. coli combining thermal (FoldME), oxidative (OxidizeME) and acid (AcidifyME) stress responses. StressME is the most up to date ME model for E. coli and it reproduces all published single-stress ME models. Additionally, it includes refined rate constants to improve prediction accuracy for wild-type and stress-evolved strains. StressME revealed certain optimal proteome allocation strategies associated with cross-stress and cross-talk responses. These stress-optimal proteomes were shaped by trade-offs between protective vs. metabolic enzymes; cytoplasmic vs. periplasmic chaperones; and expression of stress-specific proteins. As StressME is tuned to compute metabolic and gene expression responses under mild acid, oxidative, and thermal stresses, it is useful for engineering and health applications. The modular design of our open-source package also facilitates model expansion (e.g., to new stress mechanisms) by the computational biology community.

Injuries of vein and its vasa vasorum caused by venous dissection may create autologous arteriovenous fistula（AVF） in patients on maintenance hemodialysis （MHD）. Affecting the proliferation, migration, phenotypic transformation of vascular cells and extracellular matrix（ECM） remodeling of vascular wall, inflammatory reaction, hypoxia of dissected vein, negative vascular remodeling and maturation obstacle of AVF played some important roles in the occurrence of AVF maturation obstacle. As proposed by Souza et al, no-touch technique（NTT） for venous dissection was initially utilized for harvesting great saphenous vein during coronary artery bypass grafting. As compared with conventional techniques（CT） for venous dissection, NTT could alleviate the injuries of vein and its vasa vasorum and boost the postoperative patency rate of venous grafts. In recent years, NTT has also been applied for venous dissection in creating AVF in MHD patients. Thus it offers a novel surgical approach for promoting AVF maturation and lowering the incidence of AVF maturation obstacle. This review focused upon the mechanism of NTT promoting AVF maturation and lowering the incidence of maturation obstacle of AVF.

Ovarian cancer is a common tumor among women. It is often asymptomatic in the early stages, with most cases already at stage III to IVE at the time of diagnosis. Direct spread and lymphatic metastasis are the primary modes of metastasis, whereas hematogenous spread is rare. An initial diagnosis of ovarian cancer that has metastasized to the stomach is also uncommon. Therefore, clear treatment methods and prognostic data for such metastasis are lacking. In our hospital, we encountered a patient with an initial imaging diagnosis of a gastric tumor and a history of an ovarian tumor with endoscopic abdominal metastasis. Based on the characteristics of the case, the two tumors were considered to be the same. After chemotherapy, a partial response was observed in the stomach and pelvic lesions, suggesting the effectiveness of the treatment. Through three treatments of recurrence, gastroscopy confirmed the stomach to be a metastatic site. Therefore, determining the primary source of advanced tumors is crucial in guiding treatment decisions. Clinicians must approach this comprehensively, relying on thorough evaluation and personal experience.

In this article, we are concerned with the periodic solutions of first-order difference equation Δu(t−1)=f(t,u(t))−s,t∈Z,(P)\Delta u\left(t-1)=f\left(t,u\left(t))-s,\hspace{1em}t\in {\mathbb{Z}},\hspace{1.0em}\hspace{1.0em}\left(P) where s∈Rs\in {\mathbb{R}}, f:Z×R→Rf:{\mathbb{Z}}\times {\mathbb{R}}\to {\mathbb{R}} is continuous with respect to u∈Ru\in {\mathbb{R}}, f(t,u)=f(t+T,u)f\left(t,u)=f\left(t+T,u), T>1T\gt 1 is an integer, Δu(t−1)=u(t)−u(t−1)\Delta u\left(t-1)=u\left(t)-u\left(t-1). We prove a result of Ambrosetti-Prodi-type for (P)\left(P) by using the method of lower and upper solutions and topological degree. We relax the coercivity assumption on ff in Bereanu and Mawhin [1] and obtain Ambrosetti-Prodi-type results.

Microporous zeolite is commonly employed as the catalyst for selective catalytic reduction of NOx using NH3 as reducing agent (NH3‐SCR) because of its strong acidity and exceptional hydrothermal stability. However, the channel of microporous zeolite limits mass transfer under low temperature. Hierarchical porous molecular sieves can overcome the above imperfections. Hierarchical pore (microporous/mesoporous/macroporous) ZSM‐5 molecular sieves were prepared using polystyrene(PS) microspheres with different particle size as the hard templates and then the ion exchange method was utilized to introduce the active components Ce, Cu, and La. In addition, the effect of PS microspheres with different size and H2O+SO2 on denitrification performance was also investigated. The results exhibited that the specific surface area of the hierarchical pore ZSM‐5 was the smallest when the size of polystyrene microspheres was the largest. The NOx conversion of all supported hierarchical porous catalysts is more than that of supported microporous ZSM‐5 catalyst in the low temperature (200 °C), which was because that the presence of the mesopores favored diffusion‐control in the low temperature, expediting the reactant transport. Furthermore, the supported hierarchical pore ZSM‐5 catalyst exhibited excellent denitrification performance in a wide temperature range of 250–500 °C (the conversion of NOx exceeded 80 % and the N2 selectivity was approaching 100 %). More importantly, the supported hierarchical pore ZSM‐5 catalyst demonstrated notably superior water and SO2 resistance in comparison to the supported micropore ZSM‐5 catalyst. [ABSTRACT FROM AUTHOR]

Oily sludge (OS) has long been regarded as a hazardous waste, and improper disposal may lead to serious environmental concerns and human health risks. Despite various methods having been proposed and applied to the treatment of OS, the oil occurrence states and properties in sludge are rarely characterized, which may directly link to the selection and effectiveness of treatment methods. Here, confocal laser scanning microscopy (CLSM), X-ray diffraction (XRD), gas chromatography (GC), and four components (SARA) analysis were utilized to characterize the changes in the oil occurrence states and compositions in OS samples before and after high-speed stirring (HSS) treatment. Our results show a substantial reduction in the oil concentration of OS after HSS treatment (from 32.98% to 1.65%), while SARA analysis reveals a similar oil composition before and after treatment, suggesting the broad applicability of HSS in removing oil and its insignificant selectivity towards various hydrocarbon components. This is further supported by the total petroleum hydrocarbon (TPH) analysis results, which show that the separated oil phase has a hydrocarbon composition similar to that of the original OS sample. The CLSM and fluorescence analysis suggest a homogeneous distribution of oil in the sludge, with relatively light components more concentrated in the pore systems between coarse mineral particles, whereas relatively heavy components tend to coexist with clay minerals. After HSS cleaning, both light and heavy components are removed to varying degrees, but light components are preferentially removed while heavy components tend to be retained in the sludge due to adsorption by clay minerals. This is consistent with TPH analysis, where a significant decrease in n-alkanes with lower carbon numbers (n-C14 to n-C20) was observed in the residual sample. Our findings demonstrate the dynamic response of oil occurrence states and compositions to the OS treatment process and highlight the importance of characterizing these fundamental properties prior to the selection of OS treatment methods. [ABSTRACT FROM AUTHOR]