Reflection acoustic logging is a new technology for identifying geological structures around the well. It can be used to describe the geological structure, such as formation interface, fracture, and ...limestone cave. Based on the acoustic logging tool composed of the source and array receiver, the method can be used to image the geological structure around the well. Through migration imaging, the section crossing the well can be obtained in any azimuth. In the current three-dimensional (3D) display technology of reflection acoustic logging, the reflection plane around the well is always displayed as a reflection arc. The arc surface correction method can correct the arc surface in 3D imaging into a plane. According to the similarity criterion in a physical experiment and the need for practical research, we designed a scale model well experiment of dipole reflection acoustic logging. We obtained the 3D display of the reflection structure around the well by the experiment and realized the arc surface correction of the 3D display in reflection acoustic logging. The application shows the method can qualitatively describe the lateral extension length of the geological structure around the well. After the arc surface correction, the geological structure can be more accurately described.
Optical microfibers (MF), as a connection between fiber optics and nanotechnology, can realize enhanced light-matter/environment interactions, which benefit for optical sensing applications. In this ...paper, we introduce the fundamental working mechanisms of MF-based optical sensors and review their recent progress and status. We also discuss the challenges and opportunities of the MF sensors and provide some clues for future work.
Complex polysaccharides (e.g. cellulose, xylan, and chitin), the most abundant renewable biomass resources available on Earth, are mainly degraded by microorganisms in nature. However, little is ...known about the global distribution of the enzymes and microorganisms responsible for the degradation of cellulose, xylan, and chitin in natural environments. Through large‐scale alignments between the sequences released by the Earth Microbiome Project and sequenced prokaryotic genomes, we determined that almost all prokaryotic communities have the functional potentials to degrade cellulose, xylan, and chitin. The median abundances of genes encoding putative cellulases, xylanases, and chitinases in global prokaryotic communities are 0.51 (0.17–1.01), 0.24 (0.05–0.57), and 0.33 (0.11–0.71) genes/cell, respectively, and the composition and abundance of these enzyme systems are environmentally varied. The taxonomic sources of the three enzymes are highly diverse within prokaryotic communities, and the main factor influencing the diversity is the community's alpha diversity index rather than gene abundance. Moreover, there are obvious differences in taxonomic sources among different communities, and most genera with degradation potentials are narrowly distributed. In conclusion, our analysis preliminarily depicts a panorama of cellulose‐, xylan‐, and chitin‐degrading enzymatic systems across global prokaryotic communities.
Aim
Glycoside hydrolases (GHs) encoded by prokaryotes play a crucial role in the degradation of carbohydrates, which is a key step in the carbon cycle. However, their global distribution remains ...poorly understood. Here, we conducted a comprehensive investigation of the global biogeographic patterns of prokaryotic‐encoded GHs.
Location
Global.
Time period
Present.
Major taxa studied
Prokaryotes.
Methods
We conducted a global survey of GH distribution based on 10,000 samples from the Earth Microbiome Project (EMP) and 17,923 completely sequenced prokaryotic genomes. The samples were retrieved from seven continents, covering all 17 EMP Ontology environments. We evaluated the assembly process and influencing factors of GH functional genes within prokaryotic communities, and analysed the rank abundance distributions (RADs), occupancy frequency distributions (OFDs), and taxonomic sources of GH families across various environments.
Results
The median number of GH genes per thousand genes encoded by global prokaryotic communities was 9.11 (7.16–11.58), with a higher GH abundance in host‐associated communities than in free‐living communities. The median number of GH families in prokaryotic communities was 105 (86–121), with fewer families but tighter functional connections between families in host‐associated communities compared to free‐living communities. In any environment, the RAD of GH families followed a lognormal model, and their OFD was bimodal, with a strong positive correlation between the two. In addition, most GH families had complex and diverse taxonomic sources across different environments.
Main conclusions
This study provides a panoramic view of the functional potentials for carbohydrate degradation across prokaryotic communities under diverse environmental conditions. The composition of GHs encoded by prokaryotic communities exhibits clear habitat specificity, which is driven by a combination of biotic and abiotic factors and generated through highly deterministic assembly processes.
Diabetes is a disorder of glucose metabolism, and over 90% are type 2 diabetes. Diabetic cardiomyopathy (DCM) is one of the type 2 diabetes complications, usually accompanied by changes in myocardial ...structure and function, together with cardiomyocyte apoptosis. Our study investigated the effect of curcumin on regulating oxidative stress (OS) and apoptosis in DCM. In vivo, diabetes was induced in an experimental rat model by streptozoticin (STZ) together with high‐glucose and high‐fat (HG/HF) diet feeding. In vitro, H9c2 cardiomyocytes were cultured with high‐glucose and saturated free fatty acid palmitate. Curcumin was orally or directly administered to rats or cells, respectively. Streptozoticin ‐induced diabetic rats showed metabolism abnormalities and elevated markers of OS (superoxide dismutase SOD, malondialdehyde MDA, gp91phox, Cyt‐Cyto C), enhanced cell apoptosis (Bax/Bcl‐2, Cleaved caspase‐3, TUNEL‐positive cells), together with reduced Akt phosphorylation and increased Foxo1 acetylation. Curcumin attenuated the myocardial dysfunction, OS and apoptosis in the heart of diabetic rats. Curcumin treatment also enhanced phosphorylation of Akt and inhibited acetylation of Foxo1. These results strongly suggest that apoptosis was increased in the heart of diabetic rats, and curcumin played a role in diabetic cardiomyopathy treatment by modulating the Sirt1‐Foxo1 and PI3K‐Akt pathways.
Optimization of island microgrids should configure the module type and size in such a way that multiple objectives can be balanced. This paper presents a bioinspired optimization approach of ...microgrid sizing, with two salient features. First, the multiple objectives are categorized into four types: reliability, economy, renewable technology, and pollution. We present a triangular aggregation model, which is straightforward and cost effective to compute the fitness. Second, a bioinspired algorithm named Levy-Harmony is developed. We embed the Levy flight into the Harmony vector updating to enhance the global searching ability and, meantime, adopt a bias factor to avoid unnecessary exploration. The searching speed and accuracy are well balanced and improved. The real datasets are used for comparative studies, demonstrating the superiority of the proposed scheme against typical existing approaches.
During the past decade, research on the design and synthesis of zeolite‐like metal–organic frameworks (ZMOFs) has developed greatly. As an important subclass of ZMOFs, zeolite‐like cluster organic ...frameworks (ZCOFs) built from 4‐connected metal‐cluster secondary building units (SBUs) and appropriate linear organic ligand bridges have attracted sustained interest, because such materials not only integrate the merits of inorganic zeolites, ZMOFs, and metal clusters, including interesting topologies, high surface areas, extra‐large cavities and channels, structural tunability, and unique physicochemical properties from various metal clusters, but also open up a new avenue to design and fabricate hybrid zeolite‐like materials that have many potential applications in material sciences. In this review, recent developments in ZCOFs are summarized by classifying the ZCOFs into four categories according to the composition of the SBUs: 1) ZCOFs based on metal–halide cluster SBUs, 2) ZCOFs based on metal–oxygen cluster SBUs, 3) ZCOFs based on metal–chalcogen cluster SBUs, and 4) ZCOFs based on mixed types of metal‐cluster SBUs. Besides, challenges associated with the design and synthesis of ZCOFs and the vast potential of this area are also discussed.
A frame of reference: Zeolite‐like cluster organic frameworks (ZCOFs) built from 4‐connected metal‐cluster secondary building units (SBUs) have attracted sustained interest due to their charming structures and potential applications in materials sciences. This Minireview presents a summary of recent advances in the development of ZCOF materials. Challenges associated with the design and synthesis of ZCOFs and the vast potential of this area are also discussed.
From a materials science point of view, graphene is essentially a polymer having a giant, two‐dimensional molecular configuration. In this Progress Report, solvated graphene and its derivatives are ...illustrated from the perspective of soft matter. Firstly, the key appealing features of graphene as a molecular building block for assembling bulk soft materials are highlighed. It is then demonstrated how the intersheet interactions in solution are correlated with the molecular structure of graphene, and how a combination of the unique molecular structure and colloidal interactions can lead to simple, solution‐phase approaches for assembling graphenes into a variety of macroscopic nanoarchitectures. A number of new exciting functions and applications are also highlighted, which are enabled by the solvation effect and in particular, it is discussed why and how solvated graphenes can offer exciting functions that are unattainable with the dried, hard counterpart. The discussion is concluded with some personal perspectives on the future directions in which this emerging class of functional soft materials could be pursued.
Solvation of graphene and its derivatives engenders a range of graphene‐based functional soft materials from colloids, amphiphiles, liquid crystals, and gels to membranes. Centered on various colloidal interactions activated via solvation, this report illustrates solvated graphenes as an emerging class of functional soft materials.
There is clear evidence that high sodium intake is associated with many health issues including hypertension and cardiovascular diseases (CVDs). Several national and worldwide studies have estimated ...deaths from CVDs attributable to high sodium. But how to evaluate the impact of high sodium intake on diseases using regional routine monitoring and investigation data is necessary and important. Our study aimed to quantitatively evaluate the high sodium intake attributed to CVDs deaths based on the routine monitoring data from China National Nutrition and Health Survey (CNNHS) in Tianjin, China. The population attributable fractions (PAF) were calculated by comparing the observed systolic blood pressure (SBP) distribution with the theoretical minimum or counterfactual distribution by sex and age groups. The results showed that CVDs deaths due to elevated SBP were 22728 (95% uncertainty intervals: 22679‐23050), accounting for 62.8% of total CVDs deaths. According to sodium intake recommended by World Health Organization (WHO), PAF of CVDs deaths attributable to high sodium diet in our study was 14.6% of total CVDs deaths, accounting for 5228 (95% UI: 5005–5998) cases. The dietary sodium intake of residents is nearly three times than sodium intake recommended by WHO. If sodium intake was reduced to reference level, the potential avoidable CVD deaths attributable to the SBP‐raising effect were more than 5200 among adults 25 aged and over in Tianjin. This evaluation method can be extended to other cities.
We examine the extent to which institutional investors herd in the U.S. corporate bond market and the price impact of their herding behavior. We find that the level of institutional herding in ...corporate bonds is substantially higher than what is documented for equities, and that sell herding is much stronger and more persistent than buy herding. The price impact of herding is also highly asymmetric. While buy herding facilitates price discovery, sell herding causes transitory yet large price distortions. Such price destabilizing effect of sell herding is particularly pronounced for speculative-grade, small, and illiquid bonds, and during the financial crisis.
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