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Dopamine antagonists, 5-HT 3 antagonists, and dexamethasone are frequently used in obstetrics to prevent postoperative nausea and vomiting (PONV). However, the superiority of any drug class is yet to be established. This network meta-analysis aimed to compare the efficacy of these antiemetics for PONV prophylaxis in women receiving neuraxial morphine for Caesarean delivery. We searched PubMed, Embase, CENTRAL, Web of Science, and Wanfang Data for eligible randomised controlled trials. Primary outcomes were the incidences of postoperative nausea (PON) and postoperative vomiting (POV) within 24 h after surgery. We used a Bayesian random-effects model and calculated odds ratios with 95% credible intervals for dichotomous data. We performed sensitivity and subgroup analyses for primary outcomes. A total of 33 studies with 4238 women were included. In the primary analyses of all women, 5-HT 3 antagonists, dopamine antagonists, dexamethasone, and 5-HT 3 antagonists plus dexamethasone significantly reduced PON and POV compared with placebo, and 5-HT 3 antagonists plus dexamethasone were more effective than monotherapy. In the subgroup analyses, similar results were seen in women receiving epidural morphine or intrathecal morphine alone but not in women receiving intrathecal morphine with fentanyl or sufentanil. However, most included studies had some concerns or a high risk of bias, and the overall certainty of the evidence was low or very low. Combined 5-HT 3 antagonists plus dexamethasone are more effective than monotherapy in preventing PONV associated with neuraxial morphine after Caesarean delivery. Future studies are needed to determine the role of prophylactic antiemetics in women receiving intrathecal morphine and lipophilic opioids. PROSPERO CRD42023454602. [ABSTRACT FROM AUTHOR]

[Display omitted] • GG/HEC had little effect on the solubilization capacity of SDS micelles for methyl benzoate (MB). • Slight MB solubility enhancement in mixed polymer-SDS systems was due to weak interactions between polymer and MB and SDS. • The weak electrostatic repulsion between HEC/GG and SDS hinders the polymer to participate into SDS micelles. • The solubilization of polymers and the solubilization of micelles proceed independently, as in a single system. • Without attractive polymer-surfactant interaction, the solubilization capacity of SDS was not improved. Micellar solubilization is considered as a key factor affecting the recovery efficiency in chemically enhanced oil recovery (cEOR). However, it is poorly understood how polymers in surfactant-polymer (SP) flooding influences the micellar solubilization. Guar gum (GG) and hydroxyethyl cellulose (HEC) are two important and widely used polysaccharide polymers. In this work, the effect of GG and HEC on the solubilization of a crude oil model compound methyl benzoate (MB) in anionic sodium dodecyl sulfate (SDS) micelles and the underlying mechanism were explored at the molecular scale by NMR spectroscopy. GG and HEC slightly increased the MB solubility in SDS micelles but did not change the solubilization capacity. No correlation peak was observed to demonstrate the attractive interaction between polymer and SDS. After examination, there is weak electrostatic repulsion between HEC/GG and SDS, which made the polymer independent from SDS micelles and was unable to participate in the formation of micelles to alter micellar structure and solubilization behavior. Although the solubility of MB was slightly increased, this increase should originate from weak molecular interactions between polymers, surfactants and hydrophobic molecules, including hydrogen bonding, van der Waals forces and hydrophobic interactions, etc. In summary, without strong electrostatic attraction between polymer and surfactant, the solubilization of polymers and the solubilization of micelles proceed independently, resulting in that the solubilization capacity of SDS micelles was not improved. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nd-Fe-B magnets with excellent properties were obtained through novel powder rounding modification. • Good flowability of the rounded powder enhanced the alignment degree of the magnet. • The thin and continuous RE-rich phase promoted the improvement of density and coercivity. • Synchronous enhancement mechanism in coercivity and remanence of the magnets was revealed. Two types of sintered Nd-Fe-B magnets were fabricated by the process of powder metallurgy technology through two different powder preparation processes i.e., conventional powder preparation process and novel powder rounding modification. The microstructure, composition and properties of the two type powders have been studied including the particle size distributions and flowabilities. Furthermore, magnetic properties, microstructure and alignment degree of the magnets prepared by the corresponding powder also have been investigated. The novel powder rounding modification rounds the sharp edges and corners of the particles compared to the conventional powder preparation process, thereby reducing friction between the particles and improving flowability of the powder. As a result, the alignment degree of the sintered magnet is enhanced, which contribute to the improvement of the remanence and the energy product density. The powder that experienced rounding process changed the distribution of RE (rare earth)-rich particles, causing tiny RE-rich particles to adhere around the main phase particles, facilitating the compact of bulk during liquid-phase sintering process and achieving uniform distribution of RE-rich phases around the Nd 2 Fe 14 B main phase, resulting in increasing the magnet density and coercivity. As a consequence, we have produced the magnet with B r = 1.43 T, H cj = 1049 kA/m and (BH) max = 393.2 kJ/m3, which is fully superior to conventional magnet with B r = 1.41 T, H cj = 969 kA/m and (BH) max = 383.7 kJ/m3 by adopting powder rounding process. This indicates that the novel powder rounding modification is an efficient approach for synchronous improvement of magnetic performance of sintered Nd-Fe-B without any heavy rare earth elements. [ABSTRACT FROM AUTHOR]

Vehicular Edge Computing (VEC) is a promising paradigm for providing low-latency and high-reliability services in the Internet of Vehicles (IoV). The increasing number of mobile devices and the diverse resource requirements of the growing IoV have resulted in a shift from centralized resource management to a decentralized approach. This shift offers improved fault tolerance, scalability, and privacy preservation. However, constructing collaborative awareness and coordination mechanisms between multiple vehicles and edge nodes in a decentralized manner is a challenge. To address this issue, we propose a decentralized many-to-many task offloading method that aims to minimize the average task completion latency of vehicles. In this study, we propose a data-sharing mechanism between vehicles and edge servers using the digital twin service, which provides global environmental perceptions to the vehicles by a low-cost approach. Additionally, we develop a mean-field multi-agent reinforcement learning algorithm to generate coordinated task offloading schemes. Instead of interacting with multiple agents, the vehicle only needs to respond to the mean action of the environment. Based on this transition, the agent generates coordinated task offloading decisions in complex scenarios. We evaluate the performance of our method using real urban traffic data. Experiment results verify the efficiency of our proposed method. [ABSTRACT FROM AUTHOR]

[Display omitted] • Both HF-NMR and LF-NMR methods were used to analyze edible bird's nests. • Forty-one components were identified and quantified and the nutrients were analyzed. • The geographical markers of each origin were accurately identified by using pattern recognition. • Adulteration was effectively identified through the LF-NMR method. Edible bird's nest (EBN) is a high-value health food with various nutrients and bioactive components. With increasing demand for EBN, they are often adulterated with cheaper ingredients or falsely labeled by the origin information, thus harming consumer interests. In this study, high- and low-field nuclear magnetic resonance (HF/LF-NMR) technology combined with multivariate statistical analysis was used to identify the geographical marker of EBN from different origins and authenticate the adulterated EBN with various adulterants at different adulteration rates. Authentic EBN samples from Malaysia were used to simulate adulteration using gelatin (GL), agar (AG) and starch (ST) at 10 %, 20 %, 40 %, 60 %, 80 %, and 100 % w/w, respectively. The results showed significant differences in composition among EBN from different origins, with isocaproate and citric acid serving as geographical markers for Malaysia and Vietnam, respectively. Leucine, glutamic acid, and N-acetylglycoprotein serving as geographical markers for Indonesia. In addition, PLS model further verified the accuracy of origin identification of EBN. The LF-NMR results of adulteration EBN showed a linear correlation between the transverse relaxation (T 2 , S 2) and the adulterated ratio. The OPLS-DA based on T 2 spectra could accurately identify authentic EBN from adulterated with GL, AG and ST at 40 %, 20 %, and 20 %, respectively. Fisher discrimination model was able to differentiate at 20 %, 20 %, and 40 %, respectively. These results show that the 1H NMR combined with multivariate statistical analysis method could be a potential tool for the detection of origin and adulteration of EBN. [ABSTRACT FROM AUTHOR]