Search Results (11)

Umami is a fundamental taste sensation, often described as a delicious and pleasant flavor perception. To enhance or complement the original flavor and meet the tastes of diverse regions, umami dipeptides have been extensively utilized in global food manufacturing. Currently, the application and purification techniques of dipeptides are relatively mature, while their umami mechanisms and molecular modification are both scarce. In this work, the 3D structure of the umami dipeptide target T1R1/T1R3 was first obtained through sequence alignment and homology modeling, then followed by the successful construction of a database containing 400 samples of dipeptides. Subsequently, the complex models of T1R1/T1R3, respectively, with DG (Asp-Gly) and EK (Glu-Lys) (i.e., T1R1_DG/T1R3, T1R1/T1R3_DG, T1R1_EK/T1R3, and T1R1/T1R3_EK) were obtained via molecular docking and virtual screening. Finally, based on comparative molecular dynamics (MD) simulation trajectories, the binding free energy was calculated to investigate receptor–ligand recognition and conformational changes, providing some implications for potential modifications of umami dipeptides. T1R1 tends to bind relatively small umami dipeptides, whereas T1R3 does the opposite, both of which favor the recognition of acidic and hydrophilic dipeptides. By comparing strategies such as hydroxyl introduction and chain length alteration, electrostatic effects may be more important than non-polar effects in molecular design. This work not only explores the recognition mechanism of umami dipeptides with the receptor T1R1/T1R3 showing certain theoretical significance, but also provides feasible suggestions for dipeptide screening and modification having certain application value. Full article

While the core objective of the Paris Agreement is to limit the increase in global average temperature (GAT) to 2 °C in the 21st century and to work towards limiting it to 1.5 °C, globalization and the configuration of production processes around global value chains (GVCs) have emerged as key factors explaining the recent evolution of environmental and economic indicators. In this context, this paper takes trade-implied carbon emissions as the entry point of the problem, uses MRIO to calculate the production-side and consumption-side carbon emissions, measures the forward and backward production lengths of GVCs according to the WWYZ method, and then constructs an econometric regression model to empirically analyze the environmental effects of GVC embeddedness. The results of the study show that, firstly, the forward and backward production length of GVCs is positively correlated with the production-side and consumption-side carbon emissions. Forward production length has a greater impact on carbon emissions on the production side, and backward production length has a greater impact on carbon emissions on the consumption side. Secondly, compared with developed countries, the length of forward and backward production has a more pronounced positive impact on carbon emissions in developing countries. Thirdly, as the global production chain continues to extend, the scale effect, structural effect, technological effect, and environmental regulation effect will all contribute to carbon emissions. Accordingly, countries or regions should continuously optimize production layout and processes to reduce the length of the production chain, realize lean manufacturing through automation and intelligence, and then move up the global value chain to play a role in carbon emission reduction through structural upgrading, technological progress, and environmental regulation. Full article

This study evaluates the hydrodynamic performance of a movable fish cage equipped with a spread mooring system in offshore condition. It investigates the global behavior and safety of a mooring system under environmental influences such as waves, currents, and biofouling. A numerical model was developed using the Cummins equation and a lumped-mass line model to capture the coupling effects between the floating structure and mooring lines. The steel frame was modeled using Morison members, whereas fishing nets were represented by a screen model incorporating drag forces. Parametric studies were performed to assess the effects of varying mooring line lengths, current speeds, and biofouling on cage behavior. Evidently, heavier chains reduced excursions but increased tension, whereas high current speeds increased the line tension (owing to increased drift) and mooring line stiffness by up to 66%. Biofouling increased the maximum excursion by 6% and line tension by up to 17%. Safety evaluations based on the American Bureau of Shipping rules examined intact and damaged conditions, comparing estimated line tensions with allowable values. The findings confirm that the mooring system ensures reliable station-keeping performance even under challenging conditions, validating its suitability for offshore deployment and ensuring the safety and stability of floating fish cage systems. Full article

This paper constructs and optimizes, for the first time, the decomposition framework of inter-city outflow and export from the urban scale and analyzes the basic characteristics of China’s urban manufacturing industry’s participation in the global value chain and national value chain from the perspective of temporal and spatial evolution. The results show that the participation index of the manufacturing industry in coastal cities is higher than that in inland cities, and inland cities are more inclined to rely on the domestic value chain to obtain superior resources for the development of the manufacturing industry. The indicators of the manufacturing industry in the cities of the province show excellent performance, while the indicators of the peripheral cities show poor characteristics. At the same time, the length index of the global value chain of the coastal city manufacturing industry is also consistent with the actual development of the urban manufacturing industry in China. The performances of China’s urban manufacturing industry in participating in the global value chain and the domestic value chain are different. Under the background of the new development pattern, the effective docking of the double chains should be realized to achieve high-quality development in the manufacturing industry. Full article

Diabetic kidney disease (DKD) represents a major global health problem. Accelerated ageing is a key feature of DKD and, therefore, characteristics of accelerated ageing may provide useful biomarkers or therapeutic targets. Harnessing multi-omics, features affecting telomere biology and any associated methylome dysregulation in DKD were explored. Genotype data for nuclear genome polymorphisms in telomere-related genes were extracted from genome-wide case–control association data (n = 823 DKD/903 controls; n = 247 end-stage kidney disease (ESKD)/1479 controls). Telomere length was established using quantitative polymerase chain reaction. Quantitative methylation values for 1091 CpG sites in telomere-related genes were extracted from epigenome-wide case–control association data (n = 150 DKD/100 controls). Telomere length was significantly shorter in older age groups (p = 7.6 × 10⁻⁶). Telomere length was also significantly reduced (p = 6.6 × 10⁻⁵) in DKD versus control individuals, with significance remaining after covariate adjustment (p = 0.028). DKD and ESKD were nominally associated with telomere-related genetic variation, with Mendelian randomisation highlighting no significant association between genetically predicted telomere length and kidney disease. A total of 496 CpG sites in 212 genes reached epigenome-wide significance (p ≤ 10⁻⁸) for DKD association, and 412 CpG sites in 193 genes for ESKD. Functional prediction revealed differentially methylated genes were enriched for Wnt signalling involvement. Harnessing previously published RNA-sequencing datasets, potential targets where epigenetic dysregulation may result in altered gene expression were revealed, useful as potential diagnostic and therapeutic targets for intervention. Full article

The COVID-19 pandemic has impacted trade flows, causing a trade drop in 2020 that was especially sensitive for pharmaceutical and medical products necessary to ensure public health. The production of pharmaceutical products is dispersed in a framework of global value chains. This study aimed to provide a detailed analysis of the EU situation in the sector of production of chemical and pharmaceutical products, to discover the fragmentation of production chains within the EU as well as globally. International inter-country input–output tables were employed to disaggregate the value-added created in EU member states. The GVC and RVC participation indexes, backward and forward participation, length of sourcing, and selling value chains were calculated and compared with the main global hubs. Full article

Methane production from livestock farming is recognized as an important contributor to global GHGs. Volatile fatty acids (VFAs) found in bovine rumen may be utilized as a substrate for methanogens to form CH₄, and thus improvement of quantitative VFA measurements can help facilitate greater understanding and mitigation of CH₄ production. This study aims to contribute to the development of more accurate methods for the quantification and specification of VFAs in bovine rumen. The VFAs were analyzed using the conventional method and an alternative catalytic esterification reaction (CER) method. Substantial differences in the detected concentrations of the C3+ VFAs (chain length ≥ 3) were observed between both methods, especially for butyric acid. Evaluation of the sensitivity of both methods to detecting the VFA concentrations in standard solutions confirmed that the values resulting from the CER method were closer to the known concentrations of the standard solution than those from the conventional method. The results of this study provide the first quantitative proof to show the improved accuracy of the measurements of C3+ VFAs when using the CER method compared with the conventional method. Therefore, the CER method can be recommended to analyze the VFAs found in rumen, especially butyric acid and other C3+ VFAs. Full article

The expansion of global production networks has raised many important questions about the interdependence among countries and how future changes in the world economy are likely to affect the countries’ positioning in global value chains. We are approaching the structure and lengths of value chains from a completely different perspective than has been available so far. By assigning a random endogenous variable to a network linkage representing the number of intermediate sales/purchases before absorption (final use or value added), the discrete-time absorbing Markov chains proposed here shed new light on the world input/output networks. The variance of this variable can help assess the risk when shaping the chain length and optimize the level of production. Contrary to what might be expected simply on the basis of comparative advantage, the results reveal that both the input and output chains exhibit the same quasi-stationary product distribution. Put differently, the expected proportion of time spent in a state before absorption is invariant to changes of the network type. Finally, the several global metrics proposed here, including the probability distribution of global value added/final output, provide guidance for policy makers when estimating the resilience of world trading system and forecasting the macroeconomic developments. Full article

This paper focuses on the low-end lock-in problem faced by China’s equipment manufacturing industry, which is heavily involved in the global value chain (GVC). Specifically, we use the production chain length system and total trade accounting framework to measure some physical and economic location indicators. The physical location measures the forward production length, backward production length, and the location index, whereas the economic location measures various types of value-added in industry exports. The results show that China’s equipment manufacturing industry has deepened its physical and economic low-end lock-in with the gradual deepening of China’s equipment manufacturing industry’s participation in GVC. From a segmented perspective, the manufacture of fabricated metal products (except machinery and equipment) and electrical equipment has the deepest degree of low-end lock-in physical location; the manufacture of computer, electronic, and optical products has the deepest degree of economic low-end lock-in. Therefore, China should accelerate its breakthroughs in the low-end locking dilemma and climb the GVC by adopting various measures such as accelerating the implementation of the intelligent manufacturing strategy, developing service-oriented equipment manufacturing industries, cultivating the domestic market, realizing low-carbon manufacturing, and improving enterprises’ independent innovation capabilities. Full article

A series of carbamate, thiocarbamate, and hydrazide analogues of acylhomoserine lactones (AHLs) were synthesized and their ability to modulate Vibrio fischeri-quorum sensing was evaluated. The compounds in the series exhibit variable side chain length and the possible presence of a diversely substituted phenyl substituent. Biological evaluation on the Vibrio fischeri quorum sensing system revealed that the ethyl substituted carbamate (1) display a weak agonistic activity whereas compounds with longer chain length or benzyl substituents display significant antagonistic activity. The most active compounds in the series were the 4-nitrobenzyl carbamate and thiocarbamate 7 and 11 which exhibited an IC₅₀ value of about 20 µM. These activities are in the range of other reported of AHL-structurally related quorum sensing (QS) inhibitors. Docking experiments conducted on the LuxR model showed that, compared to the natural ligand OHHL, the additional heteroatom of the carbamate group induces a new hydrogen bond with Tyr70 leading to a different global hydrogen-bond network. Tyr70 is an important residue in the binding site and is strictly conserved in the LuxR family. For the 4-nitrobenzyl carbamate and thiocarbamate analogues, the docking results highlight an additional hydrogen bond between the nitro group and Lys178. For hydrazide analogues, which are deprived of any activity, docking shows that the orientation of the carbonyl group is opposite as compared with the natural ligand, leading to the absence of a H-bond between the C=O with Tyr62. This suggests that, either this later interaction, or the influence of the C=O orientation on the overall ligand conformation, are essential for the biological activity. Full article

While software-defined networking (SDN) has been widely applied in various networking domains including datacenters, WANs (Wide Area Networks), QoS (Quality of Service) provisioning, service function chaining, etc., it also has foreseeable applications in energy internet (EI), which envisions an intelligent energy industry on the basis of (information) internet. Global awareness provided by SDN is especially useful in system monitoring in EI to achieve optimal energy transportation, sharing, etc. Link layer discovery protocol (LLDP) plays a key role in global topology discovery in software-defined energy internet when SDN is applied. Nevertheless, EI-related status information (power loads, etc.) is not collected during the LLDP-based topology discovery process initiated by the SDN controller, which makes the optimal decision making (e.g., efficient energy transportation and sharing) difficult. This paper proposes MonLink, a piggyback status-monitoring scheme over LLDP in software-defined energy internet with SDN-equipped control plane and data plane. MonLink extends the original LLDP by introducing metric type/length/value (TLV) fields so as to collect status information and conduct status monitoring in a piggyback fashion over LLDP during topology discovery simultaneously without the introduction of any newly designed dedicated status monitoring protocol. Several operation modes are derived for MonLink, namely, periodic MonLink, which operates based on periodic timeouts, proactive MonLink, which operates based on explicit API invocations, and adaptive MonLink, which operates sensitively and self-adaptively to status changes. Various northbound APIs are also designed so that upper layer network applications can make full use of the status monitoring facility provided by MonLink. Experiment results indicate that MonLink is a lightweight protocol capable of efficient monitoring of topological and status information with very low traffic overhead, compared with other network monitoring schemes such as sFlow. Full article