Abiogenesis has long been suspected to require that chemical reaction networks contain multiple autocatalytic cores, but little is known about what features of these networks allow for the gradual ...accretion of complexity. To identify realistic scenarios for the emergence of life-like properties, we develop the concept of a seed-dependent autocatalytic system (SDAS), which is a subnetwork that can autocatalytically self-maintain given a flux of food, but cannot be initiated by food alone. Rather, initiation of SDASs requires the transient introduction of chemical “seeds”. We show that, depending on the topological relationship of SDASs in a chemical reaction network, a food-driven system can accrete complexity in a historically contingent manner, governed by rare seeding events. We develop new algorithms for detecting and analyzing SDASs in chemical reaction databases and describe parallels between multi-SDAS networks and biological ecosystems. Applying our algorithms to both an abiotic reaction network and a biochemical one, each driven by a set of simple food chemicals, we detect SDASs that are organized as trophic tiers, of which the higher tier can be seeded by relatively simple chemicals if the lower tier is already activated. This indicates that sequential activation of trophically organized SDASs by seed chemicals that are not much more complex than what already exist could be a mechanism of gradual complexification from relatively simple abiotic reactions to more complex life-like systems. Interestingly, in both reaction networks, higher-tier SDASs include chemicals that might alter emergent features of chemical systems and could serve as early targets of selection. Our analysis provides computational tools for analyzing very large chemical/biochemical reaction networks and suggests new approaches to studying abiogenesis in the lab.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•FOXK2 expression is increased in HCC and significantly correlated with poor outcomes in two independent cohorts of 864 patients.•FOXK2 is identified as a direct target of miR-1271.•FOXK2 promotes ...HCC cell proliferation and migration via activation of PI3K/AKT pathway.
The forkhead transcription factor FOXK2 has been implicated in the progression of human cancers, but its role and clinical significance in hepatocellular carcinoma (HCC) have not been explored. Here we showed that FOXK2 expression was increased and associated with tumor size, TNM stage and vascular invasion. High FOXK2 expression was correlated with poor overall and disease-free survival in two independent cohorts consisting of 864 patients with HCC. The prognostic value of FOXK2 was validated by stratified survival analyses in subgroups difined by factors contributing to worse survival. Multivariate Cox regression model revealed that FOXK2 served as an independent factor for overall survival. The FOXK2 expression was reversely connected with miR-1271-5p in clinical samples. Re-introduction of miR-1271 decreased FOXK2 at both mRNA and protein levels. Luciferase assay confirmed that FOXK2 was a direct target of miR-1271 in HCC cells. Overexpression of FOXK2 enhanced the cell growth and migration, whereas FOXK2 silence resulted in the opposite phenotypes. Further studies demonstrated that FOXK2 exerted oncogenic activity via activation of PI3K/AKT signaling pathway. Collectively, our data suggest FOXK2 as an oncogene and a promising prognostic biomarker in HCC. Targeting the newly identified miR-1271/FOXK2/AKT axis may represent a potential strategy for HCC intervention.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Non-overlapping domain decomposition (DD) methods provide efficient algorithms for solving time-harmonic Maxwell equations. It has been shown that the convergence of DD algorithms can be improved ...significantly by using high order transmission conditions. In this paper, we extend a newly developed second-order transmission condition (SOTC), which involves two second-order transverse derivatives, to facilitate fast convergence in the non-conformal DD algorithms. However, the non-conformal nature of the DD methods introduces an additional technical difficulty, which results in poor convergence in many real-life applications. To mitigate the difficulty, a corner-edge penalty method is proposed and implemented in conjunction with the SOTC to obtain truly robust solver performance. Numerical results verify the analysis and demonstrate the effectiveness of the proposed methods on a few model problems. Finally, drastically improved convergence, compared to the conventional Robin transmission condition, was observed for an electrically large problem of practical interest.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Metal-organic frameworks (MOFs) have emerged as a promising electrode material for supercapacitors owing to their high porosity and a regular porous structure, however, the capacitance performance ...and/or ion conduction rate performance of most MOFs with poor electrical conductivity are greatly hindered. To increase the bulk electrical conductivity and the efficiency of MOFs, an effective method was proposed by interweaving organic conductive polymer polyaniline (PANI) and MOF crystals (ZIF-67) grown in situ. As a result, the highly conductive PANI that interlink the MOF particles (denoted as ZIF-67@PANI) increase the electron transfer between MOF particles while the effective porosity of the MOF is maintained, which greatly improves the electrical conductivity and capacitance of MOFs. Electrochemical studies indicates that the ZIF-67@PANI exhibits ultrahigh specific capacity of 1123.65 C g−1 at a current density of 1 A g−1 in a three-electrode system, superior rate capability (648.9 C g−1 at 10 A g−1 current density) and excellent cycling stability (92.3% capacity retention after 9000 cycles). Furthermore, a symmetrical supercapacitor device based on ZIF-67@PANI network exhibits ultrahigh energy density of 71.1 W h kg−1 at a power density of 504.72 W kg−1 at 1 A g−1 current density. The capacitance performance of ZIF-67@PANI-2 we report here is the best among the supercapacitor materials formed by MOFs and conductive polymers up to date, confirming the importance of hybrid materials on the nanoscale and the significance of in situ synthetic chemistry.
PANI-coated in-situ growth of ZIF-67 can greatly improve the conductivity of ZIF-67 and exhibit excellent capacitor performance. Display omitted
•The ZIF-67@PANI hybrids are prepared and exhibit excellent capacitor behaviors.•The ZIF-67@PANI-2 capacitor shows specific capacity of 2497 F g−1 at 1 A g−1 in a 3-electrode system.•The capacitance of the capacitor remains 92.3% at 5 A g−1 after 9000 cycles.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Potato is the third most important staple food crop. To address challenges associated with global food security, a hybrid potato breeding system, aimed at converting potato from a ...tuber-propagated tetraploid crop into a seed-propagated diploid crop through crossing inbred lines, is under development. However, given that most diploid potatoes are self-incompatible, this represents a major obstacle which needs to be addressed in order to develop inbred lines. Here, we report on a self-compatible diploid potato, RH89-039-16 (RH), which can efficiently induce a mating transition from self-incompatibility to self-compatibility, when crossed to self-incompatible lines. We identify the
S
-
l
ocus
i
nhibitor
(
Sli
) gene in RH, capable of interacting with multiple allelic variants of the pistil-specific S-ribonucleases (S-RNases). Further,
Sli
gene functions like a general S-RNase inhibitor, to impart SC to RH and other self-incompatible potatoes. Discovery of
Sli
now offers a path forward for the diploid hybrid breeding program.
A near-infrared fluorescent probe (TX-P) for detecting peroxynitrite is constructed. The probe has a near-infrared emission (725 nm), large Stokes shift (125 nm) and excellent sensitivity and ...selectivity. In addition, TX-P can be used to visualize ONOO
−
in living cells, image ONOO
−
in paw edema mice and evaluate anti-inflammatory drugs.
A near-infrared fluorescent probe (TX-P) for detecting peroxynitrite is constructed. The probe has long emission and large Stokes shift. TX-P can be used to visualize ONOO
−
in cells, image ONOO
−
in paw edema mice and evaluate anti-inflammatory drugs.
Despite the conceptual importance of contextuality in quantum mechanics, there is a hitherto limited number of applications requiring contextuality but not entanglement. Here, we show that for any ...quantum state and observables of sufficiently small dimensions producing contextuality, there exists a communication task with quantum advantage. Conversely, any quantum advantage in this task admits a proof of contextuality whenever an additional condition holds. We further show that given any set of observables allowing for quantum state-independent contextuality, there exists a class of communication tasks wherein the difference between classical and quantum communication complexities increases as the number of inputs grows. Finally, we show how to convert each of these communication tasks into a semi-device-independent protocol for quantum key distribution.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
Objectives
Differences in clinical adverse outcomes (CAO) based on different intestinal stricturing definitions in Crohn’s disease (CD) are poorly documented. This study aims to compare CAO between ...radiological strictures (RS) and endoscopic strictures (ES) in ileal CD and explore the significance of upstream dilatation in RS.
Methods
This retrospective double-center study included 199 patients (derivation cohort,
n
= 157; validation cohort,
n
= 42) with bowel strictures who simultaneously underwent endoscopic and radiologic examinations. RS was defined as a luminal narrowing with wall thickening relative to the normal gut on cross-sectional imaging (group 1 (G1)), which further divided into G1a (without upstream dilatation) and G1b (with upstream dilatation). ES was defined as an endoscopic non-passable stricture (group 2 (G2)). Strictures met the definitions of RS (with or without upstream dilatation) and ES were categorized as group 3 (G3). CAO referred to stricture-related surgery or penetrating disease.
Results
In the derivation cohort, G1b (93.3%) had the highest CAO occurrence rate, followed by G3 (32.6%), G1a (3.2%), and G2 (0%) (
p
< 0.0001); the same order was found in the validation cohort. The CAO-free survival time was significantly different among the four groups (
p
< 0.0001). Upstream dilatation (hazard ratio, 1.126) was a risk factor for predicting CAO in RS. Furthermore, when upstream dilatation was added to diagnose RS, 17.6% of high-risk strictures were neglected.
Conclusions
CAO differs significantly between RS and ES, and clinicians should pay more attention to strictures in G1b and G3. Upstream dilatation has an important impact on the clinical outcome of RS but may not be an essential factor for RS diagnosis.
Clinical relevance statement
This study explored the definition of intestinal stricture with the greatest significance for the clinical diagnosis and prognosis of patients with CD, and consequently provided effective auxiliary information for clinicians to formulate strategies for the treatment of CD intestinal strictures.
Key Points
• The retrospective double-center study showed that clinical adverse outcome is different between radiological strictures and endoscopic strictures in CD.
• Upstream dilatation has an important impact on the clinical outcome of radiological strictures but may not be an essential factor for diagnosis of radiological strictures.
• Radiological stricture with upstream dilatation and simultaneous radiological and endoscopic stricture were at increased risk for clinical adverse outcomes; thus, closer monitoring should be considered.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Anthropogenic activities are causing unprecedented loss of genetic diversity in many species. However, the effects on genetic diversity from large-scale grafting onto wild plants of crop species are ...largely undetermined. Iron walnut (Juglans sigillata Dode) is a deciduous nut tree crop endemic to southwestern China with a long history of cultivation. Due to the rapid expansion of the walnut industry, many natural populations are now being replaced by cultivars grafted onto wild rootstocks. However, little is known about the potential genetic consequences of such action on natural populations. We sampled the scion and the rootstock from each of 149 grafted individuals within nine wild populations of J. sigillata from Yunnan Province which is the center of walnut diversity and cultivation in China, and examined their genetic diversity and population structure using 31 microsatellite loci. Scions had lower genetic diversity than rootstocks, and this pattern was repeated in seven of the nine examined populations. Among those seven populations, AMOVA and clustering analyses showed a clear genetic separation between all rootstocks and all scions. However, the two remaining populations, both from northern Yunnan, showed genetic similarity between scions and rootstocks, possibly indicating that wild populations here are derived from feralized local cultivars. Moreover, our data indicated probable crop-to-wild gene flow between scions and rootstocks, across all populations. Our results indicate that large-scale grafting has been causing genetic diversity erosion and genetic structure breakdown in the wild material of J. sigillata within Yunnan. To mitigate these effects, we caution against the overuse of grafting in wild populations of iron walnut and other crop species and recommend the preservation of natural genotypes through in situ and ex situ conservation.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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