Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has ...been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.
Phylogenetic relationships in Rosaceae have long been problematic because of frequent hybridisation, apomixis and presumed rapid radiation, and their historical diversification has not been ...clarified.
With 87 genera representing all subfamilies and tribes of Rosaceae and six of the other eight families of Rosales (outgroups), we analysed 130 newly sequenced plastomes together with 12 from GenBank in an attempt to reconstruct deep relationships and reveal temporal diversification of this family.
Our results highlight the importance of improving sequence alignment and the use of appropriate substitution models in plastid phylogenomics. Three subfamilies and 16 tribes (as previously delimited) were strongly supported as monophyletic, and their relationships were fully resolved and strongly supported at most nodes. Rosaceae were estimated to have originated during the Late Cretaceous with evidence for rapid diversification events during several geological periods. The major lineages rapidly diversified in warm and wet habits during the Late Cretaceous, and the rapid diversification of genera from the early Oligocene onwards occurred in colder and drier environments.
Plastid phylogenomics offers new and important insights into deep phylogenetic relationships and the diversification history of Rosaceae. The robust phylogenetic backbone and time estimates we provide establish a framework for future comparative studies on rosaceous evolution.
Silver screen: The AgNO3‐catalyzed carbon phosphorylation of alkenes occurs by an alkene addition/cyclization cascade. Ag+ reacts with Ph2P(O)H to form the crucial active intermediate 1, which ...promotes the reaction. This method requires a cheap, nontoxic silver salt as the catalyst and substrates for the transformation are simple and readily accessible.
Potassium‐ion batteries (PIBs) are promising alternatives to lithium‐ion batteries because of the advantage of abundant, low‐cost potassium resources. However, PIBs are facing a pivotal challenge to ...develop suitable electrode materials for efficient insertion/extraction of large‐radius potassium ions (K+). Here, a viable anode material composed of uniform, hollow porous bowl‐like hard carbon dual doped with nitrogen (N) and phosphorus (P) (denoted as N/P‐HPCB) is developed for high‐performance PIBs. With prominent merits in structure, the as‐fabricated N/P‐HPCB electrode manifests extraordinary potassium storage performance in terms of high reversible capacity (458.3 mAh g−1 after 100 cycles at 0.1 A g−1), superior rate performance (213.6 mAh g−1 at 4 A g−1), and long‐term cyclability (205.2 mAh g−1 after 1000 cycles at 2 A g−1). Density‐functional theory calculations reveal the merits of N/P dual doping in favor of facilitating the adsorption/diffusion of K+ and enhancing the electronic conductivity, guaranteeing improved capacity, and rate capability. Moreover, in situ transmission electron microscopy in conjunction with ex situ microscopy and Raman spectroscopy confirms the exceptional cycling stability originating from the excellent phase reversibility and robust structure integrity of N/P‐HPCB electrode during cycling. Overall, the findings shed light on the development of high‐performance, durable carbon anodes for advanced PIBs.
A viable anode material composed of nitrogen/phosphorus co‐doped hollow porous bowl‐like hard carbon is developed for potassium ion batteries. The resulting anode manifests prominent merits in structure, endowing it with extraordinary K+ storage capability. The K+ storage mechanisms are revealed through in‐depth studies by combining in situ TEM studies, ex situ microscopic, and Raman spectroscopy in conjunction with DFT calculations.
The aim of the present study was to investigate the protective effects of Shenfu injection (SFI) against myocardial ischemia–reperfusion injury (MIRI) in model rats and to explore its mechanism of ...action. Sprague–Dawley (SD) rats were pretreated with SFI and NG-nitro-L-arginine methyl ester (L-NAME) via tail vein injection and then rats were subjected to ischemia by occlusion of the left anterior descending coronary artery for 30 min followed by reperfusion for 120 min. Left ventricular function was evaluated by echocardiography. Hemodynamic was measured by the Millar pressure–volume system; serum creatine kinase (CK), lactate dehydrogenase (LDH) and serum troponin (TNNI3) levels were determined. Myocardial infarct size was observed by 2,3,5-triphenyl-2H-tetrazolium chloride (TTC) staining; p-Akt/Akt, and p-endothelial nitric oxide synthase (p-eNOS)/eNOS levels were assessed by Western blotting; nitric oxide (NO) content in serum was determined by the Griess reaction. SFI significantly decreased serum CK, LDH and TNNI3 levels in MIRI rats, while it significantly increased the level of left ventricular systolic pressure (LVSP), left ventricular diastolic pressure (LVDP), maximal rate of the increase of left ventricular pressure (+dp/dtmax), maximal rate of the decrease of left ventricular pressure (−dp/dtmax), left ventricle ejection fraction percentage (EF), and stroke volume (SV). In addition, SFI significantly reduced myocardial infarction area and activated the phosphorylation of eNOS via Akt. The phosphorylation of eNOS and the concurrent increase of NO production contributed significantly to the protective effects of SFI. These results demonstrate that SFI protects the rat heart against MIRI and that this effect is mediated in part by Akt/eNOS signaling.
With the advances in innovative instrumentation and various valuable applications, near-infrared (NIR) spectroscopy has become a mature analytical technique in various fields. Variable (wavelength) ...selection is a critical step in multivariate calibration of NIR spectra, which can improve the prediction performance, make the calibration reliable and provide simpler interpretation. During the last several decades, there have been a large number of variable selection methods proposed in NIR spectroscopy. In this paper, we generalize variable selection methods in a simple manner to introduce their classifications, merits and drawbacks, to provide a better understanding of their characteristics, similarities and differences. We also introduce some hybrid and modified methods, highlighting their improvements. Finally, we summarize the limitations of existing variable selection methods, providing our remarks and suggestions on the development of variable selection methods, to promote the development of NIR spectroscopy.
•Generalize variable selection methods in a simple manner to provide a better understanding of their characteristics.•Introduce their modified and hybrid methods and highlighting their improvements.•Summarize the limitations and mention seven aspects of the problem affecting the existing variable selection methods.•Provide our remarks and suggestions on the trends of the development on the variable selection methods in NIR spectra.
Preclinical and clinical studies have suggested a neuroprotective effect of remote ischemic conditioning (RIC), which involves repeated occlusion/release cycles on bilateral upper limb arteries; ...however, robust evidence in patients with ischemic stroke is lacking.
To assess the efficacy of RIC for acute moderate ischemic stroke.
This multicenter, open-label, blinded-end point, randomized clinical trial including 1893 patients with acute moderate ischemic stroke was conducted at 55 hospitals in China from December 26, 2018, through January 19, 2021, and the date of final follow-up was April 19, 2021.
Eligible patients were randomly assigned within 48 hours after symptom onset to receive treatment with RIC (using a pneumatic electronic device and consisting of 5 cycles of cuff inflation for 5 minutes and deflation for 5 minutes to the bilateral upper limbs to 200 mm Hg) for 10 to 14 days as an adjunct to guideline-based treatment (n = 922) or guideline-based treatment alone (n = 971).
The primary end point was excellent functional outcome at 90 days, defined as a modified Rankin Scale score of 0 to 1. All end points had blinded assessment and were analyzed on a full analysis set.
Among 1893 eligible patients with acute moderate ischemic stroke who were randomized (mean SD age, 65 10.3 years; 606 women 34.1%), 1776 (93.8%) completed the trial. The number with excellent functional outcome at 90 days was 582 (67.4%) in the RIC group and 566 (62.0%) in the control group (risk difference, 5.4% 95% CI, 1.0%-9.9%; odds ratio, 1.27 95% CI, 1.05-1.54; P = .02). The proportion of patients with any adverse events was 6.8% (59/863) in the RIC group and 5.6% (51/913) in the control group.
Among adults with acute moderate ischemic stroke, treatment with remote ischemic conditioning compared with usual care significantly increased the likelihood of excellent neurologic function at 90 days. However, these findings require replication in another trial before concluding efficacy for this intervention.
ClinicalTrials.gov Identifier: NCT03740971.
A series of homo‐ and hetero‐trinuclear cobalt(II) complexes Co3(L)(OAc)2(CH3CH2OH)(H2O) (1), Co2Ba(L)(OAc)2 (2) and Co2Ca(L)(OAc)2·CHCl3 (3), containing an acyclic naphthalenediol‐based ligand H4L ...were synthesized. All the three complexes were characterized by elemental analyses, IR, UV–vis spectra and single crystal X‐ray diffraction analyses. Comparative studies of the structures and spectroscopic properties are carried out on these complexes. All of the complexes show catechol oxidase activities in MeCN. Using UV–vis spectroscopy, we monitored the aerial oxidation of 3,5‐di‐tert‐butylcatechol (3,5‐DTBCH2) to 3,5‐di‐tert‐butylquinone (3,5‐DTBQ), which confirms the essential role of these complexes in enhancing the catalytic reaction.
Three homo‐ and hetero‐trinuclear cobalt(II) complexes 1–3 have been successfully prepared with acyclic naphthalenediol‐based bis(Salamo)‐type ligand H4L, and structurally characterized. Catecholase oxidase activities of homo‐trinuclear complex 1 is performed.
Despite available clinical management strategies, chronic kidney disease (CKD) is associated with severe morbidity and mortality worldwide, which beckons new solutions. Host-microbial interactions ...with a depletion of
in CKD are reported. However, the mechanisms about if and how
can be used as a probiotic to treat CKD remains unknown.
We evaluated the microbial compositions in 2 independent CKD populations for any potential probiotic. Next, we investigated if supplementation of such probiotic in a mouse CKD model can restore gut-renal homeostasis as monitored by its effects on suppression on renal inflammation, improvement in gut permeability and renal function. Last, we investigated the molecular mechanisms underlying the probiotic-induced beneficial outcomes.
We observed significant depletion of
in the patients with CKD in both Western (n=283) and Eastern populations (n=75). Supplementation of
to CKD mice reduced renal dysfunction, renal inflammation, and lowered the serum levels of various uremic toxins. These are coupled with improved gut microbial ecology and intestinal integrity. Moreover, we demonstrated that the beneficial effects in kidney induced by
-derived butyrate were through the GPR (G protein-coupled receptor)-43.
Using a mouse CKD model, we uncovered a novel beneficial role of
in the restoration of renal function in CKD, which is, at least in part, attributed to the butyrate-mediated GPR-43 signaling in the kidney. Our study provides the necessary foundation to harness the therapeutic potential of
for ameliorating CKD.
The ongoing climate change‐induced shifts in flowering phenology have emerged as a consequential force impacting biodiversity and ecosystems. Despite the globally recognized significance of flowering ...phenology as a key reproductive attribute, studies in subtropical regions have been relatively fewer, particularly in comparison to temperate and cold regions. Additionally, the nuanced response of deciduous and evergreen plants to climate change remains insufficiently explored. In addressing this gap, we built a phenological model and a generalized linear mixed effect model to assess the differential responses of key flowering phenological traits, that is, first flowering date (FFD), peak flowering date (PFD), end of flowering date (EFD), and flowering duration (FD), to climate factors (temperature and precipitation) between deciduous and evergreen plants. We observed distinct responses in flowering phenological traits to climate change between deciduous and evergreen plants. Specifically, the advancement of FFD, PFD, and EFD in deciduous in response to temperature rise exceeded that in evergreen plants. FD in evergreen plants exhibited a stronger extension to temperature increase compared to deciduous. Conversely, the phenological change of evergreen plants in response to decreasing precipitation was greater than that of deciduous ones. Since temperature is a decisive climatic factor in affecting phenological changes, climate change‐induced advances in flowering phenology of deciduous plants are still larger than evergreen plants. Projections from our phenological model under future climate scenarios (SSP 1‐2.6 and SSP 5‐8.5) indicate a continuous enlargement of difference in flowering phenology between deciduous and evergreen plants, with this trend escalating into the future (2100>2070>2050>2030). The larger extension in FD of evergreens to climate change suggests a potential increase in their proportion within subtropical forest communities relative to deciduous plants. These insights contribute significantly to our understanding of the intricate dynamics of climate‐induced changes in subtropical plant ecosystems.
抽象的
气候变化引起的植物物候改变已对全球范围内生物多样性和生态系统产生重大影响。作为一种重要的生殖性状，开花物候研究主要集中在温带和寒冷地区，亚热带地区的研究较为少见。落叶植物和常绿植物是亚热带两种植物类型，但我们并不清楚它们开花物候对气候变化的响应会有所不同。为此，本文利用中国物候观测网的数据，建立了物候模型和广义线性混合效应模型，评估了落叶和常绿植物的4种开花物候性状，即首次开花日期 (first flowering date/FFD)、开花峰值日期 (peak flowering date /PFD)、开花结束日期 (end of flowering date /EFD)和开花持续时间 (flowering duration /FD)，对两种气候因子(温度和降水)变化的不同响应。结果发现，落叶植物和常绿植物的开花物候对气候变化响应有明显差别。其中，落叶植物的FFD、PFD和EFD对气温升高的敏感性高于常绿植物。但是，与落叶植物相比，常绿植物的FD对增温呈现出更强的延长趋势。相反，常绿植物的物候变化对降水减少的敏感性高于落叶植物；由于温度是驱动亚热带植物开花物候变化的决定性气候因子，它对降水作用的不等比抵消使得气候变化对落叶植物开花物候的影响远高于常绿植物；在SSP 1‐2.6和SSP 5‐8.5两种未来气候情景下，气候驱动的物候模型预测表明，落叶植物和常绿植物的开花物候差异将在未来持续扩大，并逐年呈上升趋势 (2100>2070>2050>2030年)；气候变化引起常绿植物FD的延长大于落叶植物，表明前者由于繁殖适合度增加，其在亚热带森林群落中的比例在未来可能不断扩大。本文研究首次揭示了气候变化对常绿和落叶植物物候差异化影响的机制。研究结果有助于了解和预测亚热带森林生态系统未来的复杂动态过程。
The ongoing climate change‐induced shifts in flowering phenology have emerged as a consequential force impacting biodiversity and ecosystems. We explore the differentiated response of flowering phenology to climate change between evergreen and deciduous species. Our results found that temperature is a key influencing factor of phenological change. Deciduous plants show more shift of flowering phenology than evergreens due to climate change, but reproductive advantages showed the opposite pattern. We predict that evergreen species will gain more competitive advantages in future subtropical forest communities.
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