This paper presents a cement-content controlled method for quality assessment and quality control of the deep soil mixing (DSM) columns in slope reinforcement. The ethylene diamine tetraacetic acid ...(EDTA) titration method was modified and used for the cement content measurement of core samples, and the effects of curing conditions and curing period on the titration results were investigated. 35 DSM columns with different construction parameters were installed in the test section, and cement content and unconfined compression tests of field core samples were conducted. The relationship between the unconfined compressive strength (UCS) and cement content of DSM columns was formulated, and the quality of DSM columns with different construction parameters was assessed. The test results suggested that the failure strength of the field cores was approximately 15-55% lower than that of laboratory samples with the same cement content. In single columns, the coefficient of variation (CV) of cement content had a negative correlation with the average failure strength and a positive correlation with the coefficient of variation of failure strength. Bidirectional mixing method, lower penetration and withdrawal velocity, more mixing blades and larger number of mixings could improve the uniformity of the DSM columns.
Volatile organic compounds (VOCs) are a class of hazardous gases that are widely present in the atmosphere and cause great harm to human health. In this paper, a ratiometric fluorescent probe ...(Dye@Eu-MOFs) based on a dye-functionalized metal–organic framework was designed to detect VOCs, which showed high sensitivity and specificity for acetaldehyde solution and vapor. A linear correlation between the integrated fluorescence intensity (I510/I616) and the concentration of acetaldehyde was investigated, enabling a quantitative analysis of acetaldehyde in the ranges of 1 × 10−4~10−5 μL/mL, with a low detection limit of 8.12 × 10−4 mg/L. The selective recognition of acetaldehyde could be clearly distinguished by the naked eye under the excitation of UV light. The potential sensing mechanism was also discussed. Significantly, a molecular logic gate was constructed based on the whole system, and finally, a molecular logic network system for acetaldehyde detection connecting basic and integrated logic operations was realized. This strategy provided an effective guiding method for constructing a molecular-level logic gate for acetaldehyde detection on a simple platform.
In this study, a red-green dual-emitting fluorescent composite (RhB@MOFs) was constructed by introducing the red-emitting organic fluorescent dye rhodamine B (RhB) into metal-organic frameworks ...(Tb-MOFs). The sample can be used as a ratiometric fluorescent probe, which not only avoids errors caused by instrument and environmental instability but also has multiple applications in detection. The results indicated that the RhB@MOFs exhibited a turned-off response toward Fe3+ and a turned-on response for the continuous detection of ascorbic acid (AA). This ratiometric fluorescent probe possessed high sensitivity and excellent selectivity in the continuous determination of Fe3+ and AA. It is worth mentioning that remarkable fluorescence change could be clearly observed by the naked eye under a UV lamp, which is more convenient in applications. In addition, the mechanisms of Fe3+- and AA-induced fluorescence quench and recovery are discussed in detail. This ratiometric probe displayed outstanding recognition of heavy metal ions and biomolecules, providing potential applications for water quality monitoring and biomolecule determination.
The flagellar motor stator is an ion channel nanomachine that assembles as a ring of the MotA
MotB
units at the flagellar base. The role of accessory proteins required for stator assembly and ...activation remains largely enigmatic. Here, we show that one such assembly factor, the conserved protein FliL, forms an integral part of the
flagellar motor in a position that colocalizes with the stator. Cryogenic electron tomography reconstructions of the intact motor in whole wild-type cells and cells lacking FliL revealed that the periplasmic domain of FliL (FliL-C) forms 18 circumferentially positioned rings integrated with the 18 MotAB units. FliL-C formed partial rings in the crystal, and the crystal structure-based full ring model was consistent with the shape of the rings observed in situ. Our data suggest that each FliL ring is coaxially sandwiched between the MotA ring and the dimeric periplasmic MotB moiety of the stator unit and that the central hole of the FliL ring has density that is consistent with the plug/linker region of MotB in its extended, active conformation. Significant structural similarities were found between FliL-C and stomatin/prohibitin/flotillin/HflK/C domains of scaffolding proteins, suggesting that FliL acts as a scaffold. The binding energy released upon association of FliL with the stator units could be used to power the release of the plug helices. The finding that isolated FliL-C forms stable partial rings provides an insight into the putative mechanism by which the FliL rings assemble around the stator units.
The purpose of this study was to compare the efficacy and safety of pars plana glaucoma drainage device (PP GDD) with anterior chamber glaucoma drainage device (AC GDD) for the treatment of glaucoma.
...We comprehensively searched three databases, including PubMed, EMBASE, and the Cochrane Library databases, selecting the relevant studies. The continuous variables, namely, intraocular pressure (IOP) and glaucoma medications, were pooled by the weighted mean differences (WMDs), and the dichotomous outcomes, including corneal failure incidence and overall complications incidence, were pooled by the odds ratio (ORs).
Four retrospective studies involving 275 eyes were evaluated, with 135 in the PP GDD group and 140 in the AC GDD group. The WMDs of the IOP reduction between the PP GDD group and the AC GDD group were - 1.01 mmHg (95% CI -4.05 to 2.03, p = 0.52). The WMDs of the glaucoma medications reduction between the PP GDD group and the AC GDD group were 0.23 (95% CI -0.11 to 0.56, p = 0.19). The pooled ORs comparing PP GDD group with AC GDD group were 1.01 (95% CI 0.03 to 40.76, p = 0.99) for corneal failure incidence and 1.19 (95% CI 0.68 to 2.09, p = 0.54) for overall complication incidence. There were no significant differences between PP GDD group and AC GDD group on these aspects.
Both PP GDD and AC GDD procedures had similar efficacy of reduction in the IOP and number of medications. They are also both comparable on the safety with similar incidence of corneal failure and overall complications.
To explore the relationship between dietary antioxidant indices (DAI) and glaucoma using the data from the 2005 to 2008 National Health and Nutrition Examination Survey (NHANES).
Our study comprised ...participants who completed the NHANES dietary intake interview and visual health questionnaire at age 40 or older. The intakes of the vitamins A, C, and E as well as of zinc, selenium, and magnesium were used to generate the DAI, which represents the overall antioxidant qualities. The self-report method for glaucoma diagnosis (ever been told by an eye doctor) was used. Survey logistic regression analyses were employed to investigate the association between DAI and glaucoma.
A total of 6,128 participants were included in our study. The unadjusted model's findings revealed a negative correlation between dietary antioxidant indices and self-reported glaucoma 0.93 (0.90, 0.96),
< 0.0001. For every unit increase in dietary antioxidant indices, the risks of self-reported glaucoma in model 1 (adjusted for age, sex, race, marital status and PIR) decreased by 5% 0.95 (0.90, 0.99),
= 0.02. After adjusting all the covariates (model 2), the risks of self-reported glaucoma decreased by 6% 0.94 (0.90, 0.99),
= 0.02 for each unit increase of dietary antioxidant indices. After converting DAI into classified variables (tertile), the same trend was found (
= 0.001).
In this analysis of the NHANES database, we found higher dietary antioxidant indices were associated with lower risk of glaucoma.
Abstract Many experiments support the notion that augmentation of neurotrophic factors' (NTFs) activity, especially glial cell line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic ...factor (BDNF) could prevent or halt the progress of neurodegeneration in Parkinson's disease (PD). However, application of NTFs as therapeutic agents for PD is hampered by the difficulty in delivering them to specific brain regions safely and effectively. Another potential strategy is to stimulate the endogenous expression of NTFs. In this study, we investigated the effects of Echinacoside (ECH), a monomer extracted from herbs, on rescuing dopaminergic function in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-lesioned mice. We found that oral administration of ECH (30 mg/kg/day for 14 days) to MPTP-treated mice, commencing after impairment of the nigrstriatal system, suppressed the reduction of nigral dopaminergic neurons, striatal fibers, dopamine and dopamine transporter to 134.24%, 203.17%, 147.25% and 154.72 of MPTP-lesioned animals respectively ( p < 0.05). There was a relative elevation in expression of GDNF and BDNF mRNA (2.94 and 3.75-fold) and protein (184.34% and 185.93%) in ECH treated mice compared with vehicle-treated MPTP-lesioned mice ( p < 0.05). In addition, the apoptosis cells and Bax/Bcl-2 ratio of mRNA and protein in MPTP-lesioned mice significantly increased, and these effects could be prevented by ECH. At the 7th and 14th days of ECH treatment, the gait disorder displayed obvious improvement ( p < 0.05). These findings demonstrate that ECH is probably a novel, orally active, non-peptide inducer of NTFs and inhibitor of apoptosis, and they provide preclinical support for therapeutic potential of this compound in the treatment of PD.
Many important gram-negative bacterial pathogens use highly sophisticated type III protein secretion systems (T3SSs) to establish complex host-pathogen interactions. Bacterial-host cell contact ...triggers the activation of the T3SS and the subsequent insertion of a translocon pore into the target cell membrane, which serves as a conduit for the passage of effector proteins. Therefore the initial interaction between T3SS-bearing bacteria and host cells is the critical step in the deployment of the protein secretion machine, yet this process remains poorly understood. Here, we use high-throughput cryo-electron tomography (cryo-ET) to visualize the T3SS-mediated
-host cell interface. Our analysis reveals the intact translocon at an unprecedented level of resolution, its deployment in the host cell membrane, and the establishment of an intimate association between the bacteria and the target cells, which is essential for effector translocation. Our studies provide critical data supporting the long postulated direct injection model for effector translocation.
To promote digital transformation, equal emphasis needs to be placed on digital skills development as to infrastructure development. Integral to investment in digital skills development is the ...subsequent management and evaluation of digital training programmes. This paper assesses mechanisms to ensure digital training programmes are adequately managed using a standardized data collection framework to measure an internationally accepted digital literacy index. Such an index requires an agile definition of digital literacy, responsive to the fluid nature of the digital economy. The paper also explores the extent to which a G20 advisory body may inform a nationally representative data collection strategy within the context of a data collection process that is cognizant of the evolving demands of businesses and users alike.
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