310 research outputs found
Removal of Hydrophobic Organic Compounds and Surfactants From Wastewater: Polyaphron-Enhanced Solvent Extraction and Biodegradation.
Surfactant based processes are emerging and becoming increasingly important in pollution control. A novel predispersed solvent extraction (PDSE) technique using surfactant based colloidal liquid aphrons (CLAs or polyaphrons) and colloidal gas aphrons (CGAs) for the removal of hydrophobic organic compounds (HOCs) from the aqueous phase was studied. The process involves an extraction of HOCs into CLAs, followed by a flotation using CGAs. Polyaphrons were characterized by a particle size analyzer. The size distribution was found to be bimodal. The effects of surfactant types, surfactant concentrations and storage times on the size distribution were studied. Polyaphrons have long shelf-lives and are dynamically very stable when dispersed in water. Flotation of polyaphrons was deduced to be the result of electrostatic forces between CGAs and polyaphrons. Semibatch PDSE experiments showed that the efficiency of a dye (Solvent Red 27) removal depended not only on the duration of flotation but also on the retention time after flotation. A mathematical model for a continuous countercurrent PDSE process was developed and tested using experimental data. The model predicted that the process efficiency is a function of the flowrates of CGAs and polyaphrons relative to feed water flowrate, the partition coefficient of the solute, relative sizes of polyaphrons to CGAs, and the attachment efficiency of polyaphrons to CGAs. The PDSE process is at the expense of residual surfactants in the effluent water. Therefore, batch shaker-flask experiments were conducted to study the aerobic biodegradation of surfactants and surfactant-laden HOCs in a wastewater collected from a local Superfund site. Results on four commercial surfactants showed that linear primary alkyl sulphates (sodium dodecyl sulfate, SDS) and linear primary alcohol ethoxylates (Witconol) exhibited better biodegradation potential than linear primary alkylbenzenesulfonates (sodium dodecylbenzenesulfonate, SDBS) and linear secondary alcohol ethoxylates (Tergitol). Increased surfactant concentrations above the critical micellar concentrations (CMCs) showed inhibitory effects, lower biodegradability and foam degradation. A plant based natural surfactant (Ritha) performed better than commercial surfactants in terms of biodegradability at concentrations above CMC, but exhibited poorer foam degradation. Results indicated that surfactant-laden HOC effluent is nutrient-limiting. Addition of surfactants also enhanced the biodegradation of HOCs
Diet-induced bacterial immunogens in the gastrointestinal tract of dairy cows: Impacts on immunity and metabolism
Dairy cows are often fed high grain diets to meet the energy demand for high milk production or simply due to a lack of forages at times. As a result, ruminal acidosis, especially subacute ruminal acidosis (SARA), occurs frequently in practical dairy production. When SARA occurs, bacterial endotoxin (or lipopolysaccharide, LPS) is released in the rumen and the large intestine in a large amount. Many other bacterial immunogens may also be released in the digestive tract following feeding dairy cows diets containing high proportions of grain. LPS can be translocated into the bloodstream across the epithelium of the digestive tract, especially the lower tract, due to possible alterations of permeability and injuries of the epithelial tissue. As a result, the concentration of blood LPS increases. Immune responses are subsequently caused by circulating LPS, and the systemic effects include increases in concentrations of neutrophils and the acute phase proteins such as serum amyloid-A (SAA), haptoglobin (Hp), LPS binding protein (LBP), and C-reactive protein (CRP) in blood. Entry of LPS into blood can also result in metabolic alterations. Blood glucose and nonesterified fatty acid concentrations are enhanced accompanying an increase of blood LPS after increasing the amount of grain in the diet, which adversely affects feed intake of dairy cows. As the proportions of grain in the diet increase, patterns of plasma β-hydoxybutyric acid, cholesterol, and minerals (Ca, Fe, and Zn) are also perturbed. The bacterial immunogens can also lead to reduced supply of nutrients for synthesis of milk components and depressed functions of the epithelial cells in the mammary gland. The immune responses and metabolic alterations caused by circulating bacterial immunogens will exert an effect on milk production. It has been demonstrated that increases in concentrations of ruminal LPS and plasma acute phase proteins (CRP, SAA, and LBP) are associated with declines in milk fat content, milk fat yield, 3.5% fat-corrected milk yield, as well as milk energy efficiency
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On the Measurements of Individual Particle Properties Via Compression and Crushing
An experimental study is presented to measure the elastic, yielding, and crushing properties of individual particles under compression using substrates made of aluminum alloy, stainless steel, and sapphire. Carefully selected, highly spherical individual Ottawa sand particles of 0.75-1.1 mm in nominal diameter were compressed between two smooth substrates, and the load-deformation curves were analyzed by Hertz elastic contact theory to derive their reduced modulus and Young\u27s modulus as well as yielding and crushing strengths, which vary significantly with the type of substrate materials. Further analysis of the yielding and plastic deformation at the particle-substrate contact shows that the yield strength or hardness of the substrate materials dominates the local contact behavior and hence affects the measured apparent yielding and crushing strengths. The two softer substrates (aluminum alloy and stainless steel) actually lead to underestimated apparent shear yield strengths of quartz particles by 60.4% and 54.2%, respectively, which are actually the yielding of substrates, while the true particle yielding occurs in the sapphire-particle contact. Moreover, the two softer substrates cause much overestimated crushing strengths of the quartz particles by 50.4% and 36.4%, respectively. Selection of inappropriate substrate materials and inappropriate interpretation of the particle-substrate contact can lead to significant errors in the measured yielding and crushing strengths. It is recommended that single particle compression testing uses substrates with yield strength greater than that of the tested particles and result interpretation also considers the elastic and yielding behaviors of the substrates. (C) 2021 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V
Open-TransMind: A New Baseline and Benchmark for 1st Foundation Model Challenge of Intelligent Transportation
With the continuous improvement of computing power and deep learning
algorithms in recent years, the foundation model has grown in popularity.
Because of its powerful capabilities and excellent performance, this technology
is being adopted and applied by an increasing number of industries. In the
intelligent transportation industry, artificial intelligence faces the
following typical challenges: few shots, poor generalization, and a lack of
multi-modal techniques. Foundation model technology can significantly alleviate
the aforementioned issues. To address these, we designed the 1st Foundation
Model Challenge, with the goal of increasing the popularity of foundation model
technology in traffic scenarios and promoting the rapid development of the
intelligent transportation industry. The challenge is divided into two tracks:
all-in-one and cross-modal image retrieval. Furthermore, we provide a new
baseline and benchmark for the two tracks, called Open-TransMind. According to
our knowledge, Open-TransMind is the first open-source transportation
foundation model with multi-task and multi-modal capabilities. Simultaneously,
Open-TransMind can achieve state-of-the-art performance on detection,
classification, and segmentation datasets of traffic scenarios. Our source code
is available at https://github.com/Traffic-X/Open-TransMind
Histone Deacetylase 3-Directed PROTACs Have Anti-inflammatory Potential by Blocking Polarization of M0-like into M1-like Macrophages
Macrophage polarization plays a crucial role in inflammatory processes. The histone deacetylase 3 (HDAC3) has deacetylase-independent function that can activate pro-inflammatory gene expression in LPS-stimulated M1-like macrophages and cannot be blocked by traditional small-molecule HDAC3 inhibitors. Here we employ the proteolysis targeting chimera (PROTAC) technology to target the deacetylase-independent function of HDAC3. We developed a potent and selective HDAC3-directed PROTAC, denoted P7, which induces nearly complete HDAC3 degradation at low micromolar concentrations in both THP-1 cells and human primary macrophages. P7 increases the anti-inflammatory cytokine secretion in THP-1 derived M1-like macrophages. Importantly, P7 decreases the secretion of pro-inflammatory cytokines in M1-like macrophages derived from human primary macrophages. This can be explained by the observed inhibition of macrophage polarization from M0-like into M1-like macrophage. In conclusion, we demonstrate that the HDAC3-directed PROTAC P7 has anti-inflammatory activity and blocks macrophage polarization, which demonstrates that this molecular mechanism can be targeted with small molecule therapeutics.</p
The trend of neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio in spontaneous intracerebral hemorrhage and the predictive value of short-term postoperative prognosis in patients
BackgroundNeutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) play an important role in the inflammatory response in various diseases, but the role in the course of spontaneous intracerebral hemorrhage (ICH) is unclear.MethodsThis study retrospectively collected baseline characteristics and laboratory findings, including NLR and PLR at different time points, from spontaneous ICH patients undergoing surgery between January 2016 and June 2021. Patients were scored using the modified Rankin Scale (mRS) to evaluate their functional status at 30 days post-operation. Patients with mRS score ≥3 were defined as poor functional status, and mRS score <3 was defined as good functional status. The NLR and PLR were calculated at admission, 48 h after surgery and 3–7 days after surgery, respectively, and their trends were observed by connecting the NLR and PLR at different time points. Multivariate logistic regression analysis was used to identify independent risk factors affecting the prognosis of ICH patients at 30 days after surgery.ResultsA total of 101 patients were included in this study, and 59 patients had a poor outcome at 30 days after surgery. NLR and PLR gradually increased and then decreased, peaking at 48 h after surgery. Univariate analysis demonstrated that admission Glasgow Coma Scale (GCS) score, interval from onset to admission, hematoma location, NLR within 48 h after surgery and PLR within 48 h after surgery were associated with poor 30-day prognosis. In multivariate logistic regression analysis, NLR within 48 h after surgery (OR, 1.147; 95% CI, 1.005, 1.308; P, 0.042) was an independent risk factor for 30-day after surgery prognosis in spontaneous ICH patients.ConclusionIn the course of spontaneous intracerebral hemorrhage, NLR and PLR initially increased and subsequently decreased, reaching their peak values at 48 h after surgery. High NLR within 48 h after surgery was an independent risk factor for poor prognosis 30 days after surgery in spontaneous ICH patients
Energy-effective offloading scheme in UAV-assisted C-RAN system
In this paper, we aim to minimize the total power of all the Internet of Things devices (IoTDs) by jointly optimizing user association, computation capacity, transmit power, and the location of unmanned aerial vehicles (UAVs) in an UAV-assisted cloud radio access network (C-RAN). In order to solve this non-convex problem, we propose an effective algorithm by solving four subproblems iteratively. For the user association and the computation capacity subproblems, the non-convex constraints are relaxed and the optimal solutions are obtained. For the transmit power control and the location planning subproblems, successive convex approximation (SCA) technique is used to transform the non-convex constraints into convex ones. Moreover, to obtain the suboptimal solutions, slack variables are also introduced to deal with the feasibility-check problems. The simulation results demonstrate that the proposed algorithm can greatly reduce the total power consumption of IoTDs
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