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Although current quality indicators of colonoscopy recommend 6 minutes as the minimum standard for withdrawal time (WT), the impact of a WT longer than 6 minutes on neoplasia detection is unclear. A multicenter randomized controlled trial involving 1027 patients was conducted from January 2018 to July 2019. Participants were randomly divided into a 9-minute (n = 514) and 6-minute (n = 513) WT group, and a timer was used to adjust the withdrawal speed. The primary outcome was the adenoma detection rate (ADR). Intention-to-treat analysis showed a significantly higher ADR in the 9-minute versus 6-minute WT group (36.6% vs. 27.1%, P =.001). Prolonging WT from 6 to 9 minutes significantly increased ADR of the proximal colon (21.4% vs. 11.9%, P <.001) as well as of the less experienced colonoscopists (36.8% vs. 23.5%, P =.001). Improvements were also observed in the polyp detection rate (58.0% vs. 47.8%, P <.001), and mean number of polyps and adenomas detected per colonoscopy (1.1 vs. 0.9, P =.002; 0.5 vs. 0.4, P =.008, respectively). The higher ADRs in 9-minute WT were also confirmed by the per-protocol (PP) analysis and subgroup analyses, with an increased rate of sessile serrated lesion detection in the 9-minute WT by PP analysis (4.0% vs. 1.3%, P =.04). Multivariate logistic regression demonstrated that the 9-minute WT was independently associated with increased ADR (P =.005). Prolonging WT from 6 to 9 minutes significantly improved ADR, especially in the proximal colon and for less experienced colonoscopists. A 9-minute WT benchmark should be considered as one of the quality indicators of colonoscopy. ClinicalTrials.gov (identifier, NCT03399045) [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, an advanced photocatalyst, B-TiO 2 /MgAl-CLDH, was synthesized and applied in cement mortar. The photocatalytic NO x degradation ability of cement mortar containing B-TiO 2 /MgAl-CLDH under different initial NO x concentrations and flow rates was investigated. The results show that B-TiO 2 /MgAl-CLDH has stronger visible light absorption, lower recombination rate of electron-hole pairs and narrower optical band gap than commercial nano-TiO 2 (P25), resulting in enhanced NO x removal efficiency. Specifically, the maximum NO x degradation ratio of B-TiO 2 /MgAl-CLDH is 23.4% within 30 min, which is about 5 times that of P25. For photocatalytic mortar, the initial NO x concentration (from 1.0 ppm to 2.0 ppm) and flow rate (from 1 L/min to 3 L/min) were positively correlated with NO x removal amount, while negatively correlated with NO x removal ratio. Based on the internal molecular diffusion properties of NO x , Langmuir-Hinshelwood and the power law kinetic models were used to predict the NO x degradation ability of photocatalytic mortar. The modeling of NO x degradation process presents a reliable prediction of the NO x removal ability of photocatalytic mortar, serving as a valuable tool for assessing the mortar's NO x removal effectiveness for policymakers and engineers. • B-TiO 2 /MgAl-CLDH exhibits a narrower band gap than B-TiO 2. • B-TiO 2 /MgAl-CLDH shows superior NO x degradation under visible light compared with B-TiO 2. • Initial NO x concentration and NO x flow rate are positively correlated with NO x removal amount. • Modeling presents a reliable prediction of the NO x degradation ability of photocatalytic mortar. [ABSTRACT FROM AUTHOR]

A numerical modelling method for lockbolted lap connections of aluminium alloy plates is studied based on experimental tests. The mechanical properties and constitutive models of aluminium alloy 6061-T6 and stainless steel 304HC were intensively determined by tensile tests. A tensile test of a single-lockbolted lap connection was conducted to obtain its elongation and strain responses. A basic numerical model that considers the lockbolt preload, interface contact and friction, and gaps between the lockbolt and bolt hole was established to simulate the tensile behaviours of this connection. This model was updated to minimize errors between the numerical and test results, and values for the friction coefficients of different contact surfaces were suggested. To improve the accuracy and efficiency of the numerical analysis, an incompatible mode solid element was adopted in the numerical model. It was determined to be better than refining the mesh or accepting a higher-precision element type. This numerical modelling method was investigated by two types of double-lockbolted connections, and its validity was verified by comparing the displacement and strain responses between the numerical and test models. The modelling method suggested in this paper is applicable for simulating the mechanical behaviours of complicated joints with lockbolted lap connections. [ABSTRACT FROM AUTHOR]

Background This research is dedicated to investigating the effects and potential mechanism of action of the aryl hydrocarbon receptor on the intestinal mucosal immune system in dextran sulfate sodium (DSS)-induced colitis. Methods Colitis was induced by the administration of 3% DSS to wild-type C57BL/6J mice for 7 days. 6-formylindolo(3, 2-b)carbazole (FICZ), an endogenous agonist of the aryl hydrocarbon receptor (AhR), was given intraperitoneally on a daily basis beginning 2 days after the start of DSS administration. The mice were weighed and assessed, and colon tissues were measured. Intraepithelial lymphocytes (IELs) were isolated from the colon and examined by flow cytometry and quantitative real-time PCR. Results FICZ ameliorated DSS-induced colitis, resulting in a reduced disease activity index and improvement in the histology and length of the colon. Colitis reduced the percentage and number of CD8αα + TCRαβ + IELs. FICZ prevented the reduction in the numbers of CD8αα + TCRαβ + IELs by upregulating the expression of the IL-15 receptor and the aryl hydrocarbon receptor (AhR), and attenuating the apoptotic rate of CD8αα + TCRαβ + IELs. Finally, IL-10 was increased and IFN-γ was decreased in CD8αα + TCRαβ + IELs by FICZ administration in DSS-induced colitis. Conclusions The results suggest that AhR activation ameliorated DSS-induced acute colitis, in a manner that is associated with the local expansion and functions of CD8αα + TCRαβ + IELs in acute colitis. The findings indicate that AhR-related ligands might be targeted as novel drug targets for IBD. [ABSTRACT FROM AUTHOR]

Targeted therapy showed broad application prospects in the treatment of various types of cancer. Through carriers such as aptamers, antibodies, proteins and peptides, targeted therapy can selectively deliver drugs into tumor cells. Compared with traditional treatment methods such as chemo- and radiotherapy, targeted drug delivery systems can reduce the toxic effects of drugs on normal cells and avoid adverse reactions. Herein, an aptamer-cyclometalated iridium(III) complex conjugate (ApIrC) has been designed and developed as a targeted anticancer agent. Owing to the targeting ability of aptamers, ApIrC specifically bound to nucleolin over-expressed on the surface of cancer cells and showed strong fluorescence signal for tumor imaging and diagnosis. ApIrC had more substantial cellular uptake in cancer cells than the iridium complex alone and exhibited favorable low toxicity to normal cells. After uptake by cells through endocytosis, ApIrC can selectively accumulated in mitochondria and induced caspase-3/7-dependent cell death. Remarkably, ApIrC can also specifically target 3D multicellular spheroids (MCSs) and show excellent tumor permeability. So, it can effectively reach the interior of MCSs and cause cell damage. To our knowledge, this is the first report of the aptamer-cyclometalated iridium(III) complex conjugate which studied for cancer targeted therapy. The developed conjugate has great potential to be developed as novel therapeutics for effective and low-toxic cancer treatment. [Display omitted] • One aptamer-cyclometalated iridium(III) complex conjugate was designed and prepared. • The conjugate specifically targeted cancer cells. • The conjugate showed much efficient tumor penetration than iridium(III) complex. • The conjugate showed less cellular uptake and low toxicity in normal cells. [ABSTRACT FROM AUTHOR]

Reactive gliosis and inflammatory reaction are common pathological change to spinal cord injury (SCI). Whereas, the effects of melatonin (MT) on the astro- and microgliosis and their related inflammatory response in the injured spinal cord are not fully understood. In this study, MT's effects on the accumulation and proliferation of microglia and astrocytes and their related inflammatory response were investigated in an acute SCI model. The effects of MT on oxidative stress, neuronal survival and behavioral performance were also tested. It was found that MT treatment significantly suppressed the accumulation and the proliferation of microglia and astrocytes. Quantitative PCR data showed that MT significantly down-regulated the pro-inflammatory markers iNOS, IL-1β and TNF-α expressions. The data showed that MT led to the rise in SOD, CAT and GSH-Px contents and the decrease in MDA content. Western blotting analysis verified that MT significantly down-regulated caspase-3, Bax and GFAP expressions, up-regulated Bcl-2 expression. Compared with the SCI vehicle-treated group, the SCI MT-treated group exhibited a greater Basso Mouse Scale (BMS) locomotor rating score. On the whole, these findings implied that MT exerts its neuroprotective effects by suppressing the accumulation and the proliferation of microglia and astrocytes and reducing the release of pro-inflammatory cytokines, which might be one of the underlying mechanisms of the MT's neuroprotective effect after SCI. Accordingly, MT may be a promising therapeutic candidate for acute SCI. • MT treatment attenuated the astro- and microgliosis and reduced the expression of the pro-inflammatory cytokines. • The reduction of secondary injury and the functional recovery may be associated with the MT's-regulated glial cell reaction and inflammatory response after SCI. • MT treatment improved the recovery of functional outcomes after SCI. [ABSTRACT FROM AUTHOR]

In this study, we synthesized 4 cyclometalated iridium complexes using N-(1,10-phenanthrolin-5-yl)picolinamide (PPA) as the main ligand, denoted as [Ir(ppy) 2 PPA]PF 6 (ppy = 2-phenylpyridine, Ir1), [Ir(bzq) 2 PPA]PF 6 (bzq = benzo[ h ]quinoline, Ir2), [Ir(dfppy) 2 PPA]PF 6 (dfppy = 2-(3,5-difluorophenyl)pyridine, Ir3), and [Ir(thpy) 2 PPA]PF 6 (thpy = 2-(thiophene-2-yl)pyridine, Ir4). Compared to cisplatin and oxaliplatin, all four complexes exhibited significant anti-tumor activity. Among them, Ir2 demonstrated higher cytotoxicity against A549 cells, with an IC 50 value of 1.6 ± 0.2 μM. The experimental results indicated that Ir2 primarily localized in the mitochondria, inducing a large amount of reactive oxygen species (ROS) generation, that decreased in mitochondrial membrane potential (MMP), reduced ATP production, and further impaired mitochondrial function, leading to cytochrome c release. Additionally, Ir2 caused cell cycle arrest at the S phase and induced apoptosis through the AKT-mediated signaling pathway. Further investigations revealed that Ir2 could simultaneously induce both apoptosis and autophagy in A549 cells, with the latter acting as a non-protective mechanism that promoted cell death. More importantly, Ir2 exhibited low toxicity to both normal LO2 cells in vitro and zebrafish embryos in vivo. Consequently, these newly developed Ir(III) complexes show great potential in the development of novel and low-toxicity anticancer agents. Four new cyclometalated iridium complexes Ir1-Ir4 were prepared and exhibited excellent cytotoxic activity. Complex Ir2 induced cell cycle arrest, mitochondrial dysfunction, apoptosis and autophagy. Complex Ir2 exhibited low toxicity to both normal LO2 cells in vitro and zebrafish embryos in vivo. [Display omitted] • Four new cyclometalated Ir(III) complexes Ir1-Ir4 were prepared and exhibited excellent cytotoxic activity. • Ir2 preferentially accumulated in mitochondria and caused a series of changes in mitochondrial events. • Complexes Ir1-Ir4 exhibited low toxicity to both normal LO2 cells in vitro and zebrafish embryos in vivo. • Ir2 could simultaneously induce both apoptosis and autophagy in A549 cells. [ABSTRACT FROM AUTHOR]

• Introduces the BTWTB method, using machine learning and probability to replace complex matrix computations in tensegrity pre-stress calculations. • Recasts force determination in tensegrity structures as an inverse problem focusing on zero structural displacement. • Demonstrates BTWTB's versatility and effectiveness on diverse tensegrity structures with minimal error and iterations. • BTWTB shows remarkable accuracy and efficiency in pre-stress determination compared to traditional methods. Tensegrity structures, known for their rigidity derived from feasible pre-stresses, present unique challenges in structural engineering. Traditional force-finding methods, though comprehensive, rely heavily on intricate matrix computations, making them computationally intensive and often uncomfortable for considering external loads in practical engineering scenarios. This paper introduces a novel approach to compute pre-stresses in cable dome structures by integrating machine learning and probability theory, collectively termed the boosting tree with bootstrap technique (BTWBT). This method reduces the sample size to as few as 100 per iteration, while improving computational efficiency by randomly generating internal forces. By reframing the force determination as an inverse problem, it ensures that structural displacement converges to zero under feasible pre-stresses. The effectiveness of BTWBT is demonstrated across three distinct cable dome structures: the Geiger dome, Kiewitt dome, and rotating hyperboloid cable dome. Results show that BTWBT achieves the preset displacement requirement (maximum nodal displacement below 0.01 mm) with fewer iterations and reduced computational cost compared to traditional machine learning methods. BTWBT's capability to manage complex structural configurations with minimal data, while incorporating random internal force generation ranges, highlights its potential as a superior alternative for force determination in tensegrity structures. [ABSTRACT FROM AUTHOR]

This paper describes a newly developed negative Gaussian cable-strut structure. It focuses on the fracture of a member using an experimental model and the corresponding vector form intrinsic finite element (VFIFE) model. First, this study considered the VFIFE algorithm for bars, cables, and beams. Next, an experimental model of a negative Gaussian curvature cable dome with its supporting system and the corresponding VFIFE model were built. Then, the given ridge cable was fractured using a shear force, and the structural dynamic response during fracture was tested. Finally, to further study the influence of fracture on the structure, different sections of three main ridge cables were selected, and their fractures were successively simulated using the VFIFE model. The results indicated that the VFIFE was an efficient and accurate way to simulate the member fracture of a negative Gaussian curvature cable dome. Furthermore, the results confirmed that members in a section with a negative curvature not only have a much greater effect on the structure but also are much more sensitive to member fracture. [ABSTRACT FROM AUTHOR]

• The average secretion level of MT in Tibetan sheep blood was highest occurred during diestrus and the lowest during proestrus. In addition, the secretion level of MT at night was significantly higher than that at day. • This study found that MTNR1A was distributed in all tissues of HPGA during the estrous cycle in Tibetan sheep, and there were significant differences in the expression of MTNR1A in various tissues. • This study found that there were also significant differences in the expression of MTNR1A mRNA in HPGA during oestrus cycle in Tibetan sheep. • The differences in MT secretion pattern and the expression of MTNR1A in HPGA suggest that they may be affected by steroid hormone secretion during the estrous cycle of Tibetan sheep. The melatonin 1A receptor (MTNR1A) is a membrane receptor distributed across the mammalian gonadal axis-associated membrane. Melatonin (MT) can specifically bind with MTNR1A on the cell membrane and regulates mammalian reproductive activities. However, the role of MTNR1A in regulating the reproductive physiological activities of sheep in the Tibetan Plateau remains unclear. In this study, the MT content in Tibetan sheep blood during the estrous cycle was detected by ELISA. The distribution of MTNR1A in the hypothalamus-pituitary–gonadal axis (HPGA) was analyzed by immunohistochemistry and immunofluorescence. Western blot and qRT-PCR were used to detect dynamic changes of MTNR1A mRNA and protein expression, and the protein distributions in the HPGA. The results showed that the average secretion level of MT in Tibetan sheep blood was highest occurred during diestrus and the lowest during proestrus. Additionally, the secretion of MT at night was significantly higher than during the day. The immunopositive products of MTNR1A were primarily distributed around the glial cells in the dorsal hypothalamic nucleus region, chromophobe cells, and eosinophilic cytoplasm in the pituitary gland, follicular granular layer, follicular adventitia, tubal mucosa, cilia, endometrium, interstices, and glands in the uterus. The expression trends of MTNR1A mRNA and proteins in the HPGA during the estrous cycle were the same. The relative expression levels of MTNR1A mRNA and proteins in the hypothalamus and ovaries were the highest during proestrus and the lowest during metestrus; the highest during diestrus in the pituitary and oviducts; the highest during metestrus in the uterus. Collectively, the differences in the secretion of MT in Tibetan sheep blood and the expression of MTNR1A in HPGA suggest that they may be affected by steroid hormone secretion during the estrous cycle of Tibetan sheep, which has a potential impact on the regulation of animal estrous cycle. [ABSTRACT FROM AUTHOR]

Matching objects across multiple cameras with non-overlapping views is a necessary but difficult task in the wide area video surveillance. Owing to the lack of spatio-temporal information, only the visual information can be used in some scenarios, especially when the cameras are widely separated. This paper proposes a novel framework based on multi-feature fusion and incremental learning to match the objects across disjoint views in the absence of space–time cues. We first develop a competitive major feature histogram fusion representation (CMFH 1 1 CMFH is the abbreviation of Competitive Major Feature Histogram fusion representation. ) to formulate the appearance model for characterizing the potentially matching objects. The appearances of the objects can change over time and hence the models should be continuously updated. We then adopt an improved incremental general multicategory support vector machine algorithm (IGMSVM 2 2 IGMSVM is the abbreviation of Incremental General Multicategory Support Vector Machine learning algorithm. ) to update the appearance models online and match the objects based on a classification method. Only a small amount of samples are needed for building an accurate classification model in our method. Several tests are performed on CAVIAR, ISCAPS and VIPeR databases where the objects change significantly due to variations in the viewpoint, illumination and poses. Experimental results demonstrate the advantages of the proposed methodology in terms of computational efficiency, computation storage, and matching accuracy over that of other state-of-the-art classification-based matching approaches. The system developed in this research can be used in real-time video surveillance applications. [ABSTRACT FROM AUTHOR]

The structural stiffness of a cable-struts structure is dependent on its feasible pre-stresses. The search for the pre-stresses is an inverse problem, and classical approaches for this problem include the singular value decomposition (SVD) method. Driven by the need for more efficient methods, this study proposes a control method to search for feasible pre-stresses of cable-struts structures. First, we formulate the governing equation for cable-struts structures under pre-stresses and external loads. Then, we apply feedback control and use a proportional–integral–derivative (PID) controller to solve for the feasible pre-stresses based on the condition of zero structural displacements. To verify the proposed method, the study selects a Geiger dome, a Kiewitt dome and a honeycomb-type cable dome under three different loading conditions, and compares the present results against those from literature. The comparison shows that the developed control method can efficiently and accurately determine the feasible pre-stresses under external loads. The relative errors in the pre-stresses determined using the PID controller and using another two methods (singular value decomposition and iterative method) are less than 0.020% and 0.015% for the Geiger dome and the honeycomb-type dome, respectively. This study contributes to developing efficient methods for design of cable-struts structures under complex service loads. • This study formulates the governing equation for cable-struts structures under pre-stresses and external loads. • This study proposes a PID-based control method to search for feasible pre-stresses of cable-struts structures. • The PID controller can efficiently and accurately determine the feasible pre-stresses under external loads. • This study provides a first attempt to apply control methods to the pre-stresses determination. [ABSTRACT FROM AUTHOR]

• This study proposes a new control equation of feasible pre-stresses and the corresponding solving algorithm. • The solving algorithm can efficiently and accurately address the feasible pre-stresses of cable domes regardless of the loads. • Three new types of rotating surface cable domes developed in the study are feasible in nature. • This study extends cable domes from the traditional positive Gaussian curvature to the zero Gaussian and negative Gaussian curvature. The study proposes the control equation of feasible pre-stresses and the corresponding solving algorithm, and verifies three new types of rotating surface cable domes. First, the study takes that the structural displacements are zero as the control equation of feasible pre-stresses, and proposes a novel solving algorithm based on that target values of structural displacements are zero. Second, the study develops three new types of cable domes with different rotating surfaces, which have different Gaussian curvature. And then their feasibility in nature are verified through determining their feasible pre-stresses using the solving algorithm. Last, their ultimate bearing capacity under full and half-span vertical loads are investigated. The results indicate that the solving algorithm can determine the feasible pre-stresses efficiently and accurately, and three new cable domes proposed in the study are feasible in nature, and they have sufficient stiffness to bear external loads. The appearance of the three new rotating surface cable domes extends the cable domes from the traditional positive Gaussian curvature to the zero Gaussian and negative Gaussian curvature. [ABSTRACT FROM AUTHOR]