The high storage capacity versus high selectivity trade‐off barrier presents a daunting challenge to practical application as an acetylene (C2H2) adsorbent. A structure–performance relationship ...screening for sixty‐two high‐performance metal–organic framework adsorbents reveals that a moderate pore size distribution around 5.0–7.5 Å is critical to fulfill this task. A precise pore space partition approach was involved to partition 1D hexagonal channels of typical MIL‐88 architecture into finite segments with pore sizes varying from 4.5 Å (SNNU‐26) to 6.4 Å (SNNU‐27), 7.1 Å (SNNU‐28), and 8.1 Å (SNNU‐29). Coupled with bare tetrazole N sites (6 or 12 bare N sites within one cage) as high‐density H‐bonding acceptors for C2H2, the target MOFs offer a good combination of high C2H2/CO2 adsorption selectivity and high C2H2 uptake capacity in addition to good stability. The optimized SNNU‐27‐Fe material demonstrates a C2H2 uptake of 182.4 cm3 g−1 and an extraordinary C2H2/CO2 dynamic breakthrough time up to 91 min g−1 under ambient conditions.
Benchmark metal–organic framework (MOF) adsorbents for C2H2/CO2 separation are reported. The MOFs offer moderate pore size distributions, which are regulated by precise pore space partitions and coupled with a high‐density of hydrogen‐bonding acceptors.
Besides the conventional carbon sources, acetyl-CoA has recently been shown to be generated from acetate in various types of cancers, where it promotes lipid synthesis and tumour growth. The ...underlying mechanism, however, remains largely unknown. We find that acetate induces a hyperacetylated state of histone H3 in hypoxic cells. Acetate predominately activates lipogenic genes ACACA and FASN expression by increasing H3K9, H3K27 and H3K56 acetylation levels at their promoter regions, thus enhancing de novo lipid synthesis, which combines with its function as the metabolic precursor for fatty acid synthesis. Acetyl-CoA synthetases (ACSS1, ACSS2) are involved in this acetate-mediated epigenetic regulation. More importantly, human hepatocellular carcinoma with high ACSS1/2 expression exhibit increased histone H3 acetylation and FASN expression. Taken together, this study demonstrates that acetate, in addition to its ability to induce fatty acid synthesis as an immediate metabolic precursor, also functions as an epigenetic metabolite to promote cancer cell survival under hypoxic stress.
A strategy called ultramicroporous building unit (UBU) is introduced. It allows the creation of hierarchical bi‐porous features that work in tandem to enhance gas uptake capacity and separation. ...Smaller pores from UBUs promote selectivity, while larger inter‐UBU packing pores increase uptake capacity. The effectiveness of this UBU strategy is shown with a cobalt MOF (denoted SNNU‐45) in which octahedral cages with 4.5 Å pore size serve as UBUs. The C2H2 uptake capacity at 1 atm reaches 193.0 cm3 g−1 (8.6 mmol g−1) at 273 K and 134.0 cm3 g−1 (6.0 mmol g−1) at 298 K. Such high uptake capacity is accompanied by a high C2H2/CO2 selectivity of up to 8.5 at 298 K. Dynamic breakthrough studies at room temperature and 1 atm show a C2H2/CO2 breakthrough time up to 79 min g−1, among top‐performing MOFs. Grand canonical Monte Carlo simulations agree that ultrahigh C2H2/CO2 selectivity is mainly from UBU ultramicropores, while packing pores promote C2H2 uptake capacity.
Hole to differentiate, and hole to accommodate. Two types of pores can mingle together using a strategy called UBU (ultramicroporous building unit). This strategy results in a promising gas absorbent for excellent C2H2 storage capacity and top‐level C2H2/CO2 separation ability.
A
bstract
We present the results of the first complete one-loop matching calculation between the real singlet scalar extension of the Standard Model and the Standard Model effective field theory ...(SMEFT) at dimension six. Beyond their immediate relevance to the precision calculation of observables in singlet extensions of the Standard Model, our results illustrate a variety of general features of one-loop matching. We explore the interplay between non-supersymmetric non-renormalization theorems, the logarithmic dependence of Wilson coefficients, and the relevance of mixed diagrams in theories with large scale separation. In addition, we highlight some of the subtleties involved in computing observables at next-to-leading order in SMEFT by mapping our results to the
T
parameter at one loop.
Hydroxyapatite nanowires exhibit a great potential in biomedical applications owing to their high specific surface area, high flexibility, excellent mechanical properties, and similarity to ...mineralized collagen fibrils of natural bone. In this work, zinc‐containing nanoparticle‐decorated ultralong hydroxyapatite nanowires (Zn‐UHANWs) with a hierarchical nanostructure have been synthesized by a one‐step solvothermal method. The highly flexible Zn‐UHANWs exhibit a hierarchical rough surface and enhanced specific surface area as compared with ultralong hydroxyapatite nanowires (UHANWs). To evaluate the potential application of Zn‐UHANWs in bone regeneration, the biomimetic Zn‐UHANWs/chitosan (CS) (Zn‐UHANWs/CS) composite porous scaffold with 80 wt % Zn‐UHANWs was prepared by incorporating Zn‐UHANWs into the chitosan matrix by the freeze‐drying process. The as‐prepared Zn‐UHANWs/CS composite porous scaffold exhibits enhanced mechanical properties, highly porous structure, and excellent water retention capacity. In addition, the Zn‐UHANWs/CS porous scaffold has a good biodegradability with the sustainable release of Zn, Ca, and P elements in aqueous solution. More importantly, the Zn‐UHANWs/CS porous scaffold can promote the osteogenic differentiation of rat bone marrow derived mesenchymal stem cells and facilitate in vivo bone regeneration as compared with the pure CS porous scaffold or UHANWs/CS porous scaffold. Thus, both the Zn‐UHANWs and Zn‐UHANWs/CS porous scaffold developed in this work are promising for application in bone defect repair.
Go nano! Zinc‐containing nanoparticle‐decorated hydroxyapatite nanowires (Zn‐UHANWs) and a biomimetic Zn‐UHANWs/chitosan (CS) (Zn‐UHANWs/CS) composite porous scaffold are synthesized. The porous scaffold exhibits enhanced mechanical properties, excellent water‐retention capacity, good biodegradability, and can promote in vivo bone regeneration (see figure).
With the growing popularity of electrical communication equipment, high-performance electromagnetic interference (EMI) shielding materials are widely used to deal with radiation pollution. However, ...the large thickness and poor mechanical properties of many EMI shielding materials usually limit their applications. In this study, ultrathin and highly flexible Ti3C2T x (d-Ti3C2T x , MXene)/cellulose nanofiber (CNF) composite paper with a nacre-like lamellar structure is fabricated via a vacuum-filtration-induced self-assembly process. By the interaction between one-dimensional (1D) CNFs and two-dimensional (2D) d-Ti3C2T x MXene, the binary strengthening and toughening of the nacre-like d-Ti3C2T x /CNF composite paper has been successfully achieved, leading to high tensile strength (up to 135.4 MPa) and fracture strain (up to 16.7%), as well as excellent folding endurance (up to 14 260 times). Moreover, the d-Ti3C2T x /CNF composite paper exhibits high electrical conductivity (up to 739.4 S m–1) and excellent specific EMI shielding efficiency (up to 2647 dB cm2 g–1) at an ultrathin thickness (minimum thickness 47 μm). The nacre-inspired strategy in this study offers a promising approach for the design and preparation of the strong integrated and flexible MXene/CNF composite paper, which may be applied in various fields such as flexible wearable devices, weapon equipment, and robot joints.
In vivo mineralization is a multistep process involving mineral‐protein complexes and various metastable compounds in vertebrates. In this complex process, the minerals produced in the mitochondrial ...matrix play a critical role in initiating extracellular mineralization. However, the functional mechanisms of the mitochondrial minerals are still a mystery. Herein, an in vitro enzymatic reaction strategy is reported for the generation of biomimic amorphous calcium phosphate (EACP) nanominerals by an alkaline phosphatase (ALP)‐catalyzed hydrolysis of adenosine triphosphate (ATP) in a weakly alkalescent aqueous condition (pH 8.0–8.5), which is partially similar to the mitochondrial environment. Significantly, the EACP nanomineral obviously promotes autophagy and osteogenic differentiation of human bone marrow‐derived mesenchymal stem cells by activating an AMPK related pathway, and displays a high performance in promoting bone regeneration. These results provide in vitro evidence for the effect of ATP on the formation and stabilization of the mineral in the mineralization process, demonstrating a potential strategy for the preparation of the biomimic mineral for treating bone related diseases.
Biomimic amorphous calcium phosphate (EACP) nanominerals are synthesized by an in vitro enzymatic reaction strategy, which promotes the autophagy and osteogenic differentiation of human bone marrow‐derived mesenchymal stem cells by activating an AMPK related pathway and displays a high performance in promoting bone regeneration.
Countering the optical network 'capacity crunch' calls for a radical development in optical fibres that could simultaneously minimize nonlinearity penalties, chromatic dispersion and maximize signal ...launch power. Hollow-core fibres (HCF) can break the nonlinear Shannon limit of solid-core fibre and fulfil all above requirements, but its optical performance need to be significantly upgraded before they can be considered for high-capacity telecommunication systems. Here, we report a new HCF with conjoined-tubes in the cladding and a negative-curvature core shape. It exhibits a minimum transmission loss of 2 dB km
at 1512 nm and a <16 dB km
bandwidth spanning across the O, E, S, C, L telecom bands (1302-1637 nm). The debut of this conjoined-tube HCF, with combined merits of ultralow loss, broad bandwidth, low bending loss, high mode quality and simple structure heralds a new opportunity to fully unleash the potential of HCF in telecommunication applications.
Abstract
Background
In gut microbiome studies, the cultured gut microbial resource plays essential roles, such as helping to unravel gut microbial functions and host-microbe interactions. Although ...several major studies have been performed to elucidate the cultured human gut microbiota, up to 70% of the Unified Human Gastrointestinal Genome species have not been cultured to date. Large-scale gut microbial isolation and identification as well as availability to the public are imperative for gut microbial studies and further characterizing human gut microbial functions.
Results
In this study, we constructed a human Gut Microbial Biobank (hGMB; homepage:
hgmb.nmdc.cn
) through the cultivation of 10,558 isolates from 31 sample mixtures of 239 fresh fecal samples from healthy Chinese volunteers, and deposited 1170 strains representing 400 different species in culture collections of the International Depository Authority for long-term preservation and public access worldwide. Following the rules of the International Code of Nomenclature of Prokaryotes, 102 new species were characterized and denominated, while 28 new genera and 3 new families were proposed. hGMB represented over 80% of the common and dominant human gut microbial genera and species characterized from global human gut 16S rRNA gene amplicon data (
n
= 11,647) and cultured 24 “most-wanted” and “medium priority” taxa proposed by the Human Microbiome Project. We in total sequenced 115 genomes representing 102 novel taxa and 13 previously known species. Further in silico analysis revealed that the newly sequenced hGMB genomes represented 22 previously uncultured species in the Unified Human Gastrointestinal Genome (UHGG) and contributed 24 representatives of potentially “dark taxa” that had not been discovered by UHGG. The nonredundant gene catalogs generated from the hGMB genomes covered over 50% of the functionally known genes (KEGG orthologs) in the largest global human gut gene catalogs and approximately 10% of the “most wanted” functionally unknown proteins in the FUnkFams database.
Conclusions
A publicly accessible human Gut Microbial Biobank (hGMB) was established that contained 1170 strains and represents 400 human gut microbial species. hGMB expands the gut microbial resources and genomic repository by adding 102 novel species, 28 new genera, 3 new families, and 115 new genomes of human gut microbes.
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