Construction of metal–organic frameworks from 3-(6-oxo-6,9-dihydro-1H-purin-1-yl)propionate

<p>A series of metal–organic frameworks built from a propionate-functionalized purine-containing ligand 3-(6-oxo-6,9-dihydro-1H-purin-1-yl)propanoic acid (H₂L), {[La(HL)₃(H₂O)₂]·2H₂O}_n (<b>1</b>), {[Ce(HL)₃(H₂O)₂]·4H₂O}_n (<b>2</b>), [Co(HL)₂(H₂O)₂]_n (<b>3</b>), {[Cd(L)(H₂O)]·0.5H₂O}_n (<b>4</b>) and {[Pb(HL)(C₂O₄)_0.5(H₂O)]·2H₂O}_n (<b>5</b>), was synthesized and characterized. Isostructural <b>1</b> and <b>2</b> have polymeric chain structures further linked into 3-D porous supramolecular frameworks with 1-D open channels through complicated interchain hydrogen bonding interactions. At 77 K and 1 bar, the dehydrated porous materials <b>1</b> and <b>2</b> show adsorption behaviors with maximum nitrogen uptakes of 14 and 23 mL g⁻¹, respectively. Complexes <b>3</b>–<b>5</b> are 2-D coordination polymers but have different topological structures. Metallohelicate <b>3</b> has (4,4) nets composed of left- and right-handed metal–organic helices sharing the common metal centers, but metallohelicate <b>4</b> possesses (4·8²) topology and <b>5</b> has 6³-topological structure. In <b>3</b> and <b>5</b>, the polymeric layers are further assembled through regular interlayer hydrogen bonding interactions to form 3-D supramolecular frameworks. Additionally, the thermostabilities of <b>1</b>–<b>5</b> as well as the magnetism of <b>3</b> were also investigated.</p

Ultrasmall NiFe-Phosphate Nanoparticles Incorporated α‑Fe₂O₃ Nanoarrays Photoanode Realizing High Efficient Solar Water Splitting

The practical application of hematite (α-Fe₂O₃) in solar water splitting is severely limited by the highly charge recombination rate though its abundant reserves and suitable bandgap of ∼2.1 eV. This work describes the synthesis of ultrasmall NiFe-phosphate (NFP) nanoparticles incorporated α-Fe₂O₃ nanoarrays photoanode via a facile dip-coating and annealing process to demonstrate combined effects on enhanced photoelectrochemical (PEC) water oxidation. The NFP uniformly decorating on the surface of hematite nanorods not only could improve water oxidation kinetics and charge separation efficiency, but also could suppress the charge recombination in company with the surface states passivation. Furthermore, the phosphate (P) in the NFP nanoparticles could also play a synergistic effect on promoting the multiproton-coupled electron transfer (PCET) process for the PEC water oxidation. All of these lead to ∼140 mV cathodic shift of onset potential, ∼2.3-fold enhancement of the photocurrent and excellent long-term stability at 1.23 V_RHE in 0.1 M KOH solution for α-Fe₂O₃/NFP photoanode. Along with these advantages, the NFP nanoparticles may possess new opportunities for modulating PEC water oxidation performances in hematite and other metal oxide photoanodes

Facile Synthesis of Carbon Supported Pd₃Au@Super-Thin Pt Core/Shell Electrocatalyst with a Remarkable Activity for Oxygen Reduction

Aiming at developing a highly active electrocatalyst with high platinum utilization efficiency, we report a facile synthesis of carbon supported Pd₃Au@Pt electrocatalyst by chemical reduction of K₂PtCl₄, K₂PdCl₄, and aq NaAuCl₄ with ascorbic acid (AA) under ambient conditions in the absence of surfactants. The resultant Pd₃Au@Pt/C electrocatalyst comprises of a thin platinum layer less than 1 nm in thickness deposited on the outer surface of Pd₃Au alloy core with an average diameter of 3.4 nm. Remarkably, Pd₃Au@Pt/C exhibited a high mass activity (MA, 939 mAmg^–1_Pt) toward oxygen reduction reaction (ORR), which is 4.6 times that of commercial Pt/C (203 mAmg^–1_Pt). The durability of Pd₃Au@Pt/C is close to that of commercial Pt/C. According to X-ray diffraction (XRD) patterns, the lattice constant of the Pd₃Au alloy supported on carbon is determined to be 3.950 Å close to yet slightly larger than that of Pt/C (3.920 Å), inducing a lateral tensile strain of the platinum shell. Meanwhile, electrons from the Pd₃Au core appear transferred to the platinum shell as evidenced by X-ray photoelectron spectroscopy (XPS). We propose that the lateral tensile strain (geometric effect) and the electron transfer (electronic effect) as well as the high platinum utilization efficiency have contributed to the significantly improved electrocatalytic activity of Pd₃Au@Pt/C. The coexistence of the lateral tensile strain and the electron transfer in the electrocatalyst with a high ORR activity has not been reported prior to this study

Visible-Light-Induced Cascade Reaction of Isocyanides and <i>N</i>‑Arylacrylamides with Diphenylphosphine Oxide via Radical C–P and C–C Bond Formation

An effective photoredox-mediated tandem phosphorylation/cyclization reaction of diphenylphosphine oxide with three types of radical acceptors leads to P­(O)­Ph₂-containing phenanthridines, isoquinolines, and indolin-2-ones by formation of both C–P and C–C bonds. [Ir­(ppy)₂(dtbpy)]­PF₆ (1 mol %) was used as the catalyst, CsF or Cs₂CO₃ as the base, and K₂S₂O₈ as the oxidant. A series of functional groups can be tolerated at room temperature. Moderate to good yields were generated

Additional file 1 of Ae index is an independent predictor of kidney stone recurrence in overweight and obese patients

Additional file 1: Table S1. Univariate analysis of patient data of overweight and obesity stone recurrence

Enhanced Performance in Al-Doped ZnO Based Transparent Flexible Transparent Thin-Film Transistors Due to Oxygen Vacancy in ZnO Film with Zn–Al–O Interfaces Fabricated by Atomic Layer Deposition

Highly conductive and optical transparent Al-doped ZnO (AZO) thin film composed of ZnO with a Zn–Al–O interface was fabricated by thermal atomic layer deposition (ALD) method. The as-prepared AZO thin film exhibits excellent electrical and optical properties with high stability and compatibility with temperature-sensitive flexible photoelectronic devices; film resistivity is as low as 5.7 × 10^–4 Ω·cm, the carrier concentration is high up to 2.2 × 10²¹ cm^–3. optical transparency is greater than 80% in a visible range, and the growth temperature is below 150 °C on the PEN substrate. Compared with the conventional AZO film containing by a ZnO–Al₂O₃ interface, we propose that the underlying mechanism of the enhanced electrical conductivity for the current AZO thin film is attributed to the oxygen vacancies deficiency derived from the free competitive growth mode of Zn–O and Al–O bonds in the Zn–Al–O interface. The flexible transparent transistor based on this AZO electrode exhibits a favorable threshold voltage and <i>I</i>_on/<i>I</i>_off ratio, showing promising for use in high-resolution, fully transparent, and flexible display applications

The purity of CD4⁺ T cells and the GFP-transfection efficiency in CD4⁺ T cells.

<p>A. CD4⁺ T cells were purified by magnetic cell sorting (MACS). The purity of CD4⁺ T cells was determined by flow cytometry and a typical FACS picture is shown. B. 2.5 µg pmaxGFP® Vector was transfected into 1×10⁷ CD4⁺ T cells by necleofection. The GFP-transfection efficiency was detected by fluorescence microscopy 8 h later and a typical 20× image (top) is shown. Same slide of CD4⁺ T cells was detected sequentially by light microscopy and the 20× image (bottom) is also shown. Both the purity and the transfection efficiency were checked in every independent experiment.</p

MiR-155 regulates the secreting of IL-17A, but not the secreting of IL-10 and TGF-β1.

<p>Pre-miR-ctrl, pre-miR-155, anti-miR-ctrl, and anti-miR-155 were transfected into CD4⁺ T cells, which were then activated and polarized. A–C. The mRNA levels of IL-17A (A), IL-10 (B) and TGF-β1 (C) were detected by RT-PCR 3 days after transfection and the collective results are shown in the left figures, respectively. While the levels of these cytokines in cell culture supernatant were detected by ELISAs 4 days after transfection and the collective results are shown in the right figures, respectively. All results are shown as mean ± SD. Data represent three independent experiments. *p<0.05, **p<0.01.</p

Data_Sheet_1_Deep learning-assisted diagnosis of large vessel occlusion in acute ischemic stroke based on four-dimensional computed tomography angiography.docx

PurposeTo develop deep learning models based on four-dimensional computed tomography angiography (4D-CTA) images for automatic detection of large vessel occlusion (LVO) in the anterior circulation that cause acute ischemic stroke.MethodsThis retrospective study included 104 LVO patients and 105 non-LVO patients for deep learning models development. Another 30 LVO patients and 31 non-LVO patients formed the time-independent validation set. Four phases of 4D-CTA (arterial phase P1, arterial–venous phase P2, venous phase P3 and late venous phase P4) were arranged and combined and two input methods was used: combined input and superimposed input. Totally 26 models were constructed using a modified HRNet network. Assessment metrics included the areas under the curve (AUC), accuracy, sensitivity, specificity and F1 score. Kappa analysis was performed to assess inter-rater agreement between the best model and radiologists of different seniority.ResultsThe P1 + P2 model (combined input) had the best diagnostic performance. In the internal validation set, the AUC was 0.975 (95%CI: 0.878–0.999), accuracy was 0.911, sensitivity was 0.889, specificity was 0.944, and the F1 score was 0.909. In the time-independent validation set, the model demonstrated consistently high performance with an AUC of 0.942 (95%CI: 0.851–0.986), accuracy of 0.902, sensitivity of 0.867, specificity of 0.935, and an F1 score of 0.901. The best model showed strong consistency with the diagnostic efficacy of three radiologists of different seniority (k = 0.84, 0.80, 0.70, respectively).ConclusionThe deep learning model, using combined arterial and arterial–venous phase, was highly effective in detecting LVO, alerting radiologists to speed up the diagnosis.</p

MiR-155 positively regulates the mRNA levels of T-bet and IFN-γ and negatively regulates the mRNA levels of GATA-3 and IL-4.

<p>Pre-miR-ctrl, pre-miR-155, anti-miR-ctrl, and anti-miR-155 were transfected into CD4⁺ T cells, which were then activated by anti-CD3 and anti-CD28. A. The mRNA levels of T-bet and IFN-γ were detected by RT-PCR 3 days after transfection and the collective results are shown, respectively. B. The mRNA levels of GATA3 and IL-4 were detected by RT-PCR 3 days after transfection and the collective results are shown, respectively. All results are shown as mean ± SD. Data represent more than three independent experiments. *p<0.05, **p<0.01.</p