High-Quality Solution-Processed Quasi-2D Perovskite for Low-Threshold Lasers

Spin-coated quasi-two-dimensional halide perovskite films, which exhibit superior optoelectronic properties and environmental stability, have recently been extensively studied for lasers. Crystallinity is of great importance for the laser performance. Although some parameters related to the spin-coating process have been studied, the in-depth understanding and effective control of the acceleration rate on two-dimensional perovskite crystallization during spin-coating are still unknown. Here we investigate the effect of solvent evaporation on the microstructure of the final perovskite films during the spin-coating process. The crystallization quality of the film can be significantly improved by controlling solvent evaporation. As a result, the prepared quasi-2D perovskite film exhibits a stimulated emission threshold (pump: 343 nm, 6 kHz, 290 fs) of 550 nm as low as 16.2 μJ/cm2. Transient absorption characterization shows that the radiative biexciton recombination time is reduced from 738.5 to 438.3 ps, benefiting from the improved crystallinity. The faster biexciton recombination significantly enhanced the photoluminescence efficiency, which is critical for population inversion. This work could contribute to the development of low-threshold lasers.

Constructing ZnTe Spherical Quantum Well for Efficient Light Emission

ZnTe colloidal semiconductor nanocrystals (NCs) have shown promise for light-emitting diodes (LEDs) and displays, because they are free from toxic heavy metals (Cd). However, so far, their low photoluminescence (PL) efficiency (∼30%) has hindered their applications. Herein, we devised a novel structure of ZnTe NCs with the configuration of ZnSe (core)/ZnTe (spherical quantum well, SQW)/ZnSe (shell). The inner layer ZnTe was grown at the surface of ZnSe core with avoiding using highly active and high-risk Zn sources. Due to the formation of coherently strained heterostructure which reduced the lattice mismatch, and the thermodynamic growth of ZnTe, the surface or interface defects were suppressed. A high PL efficiency of >60% was obtained for the green light-emitting ZnSe/ZnTe/ZnSe SQWs after ZnS outer layer passivation, which is the highest value for colloidal ZnTe-based NCs. This work paves the way for the development of novel semiconductor NCs for luminescent and display applications.

Nonadiabatic Charge Transfer within Photoexcited Nickel Porphyrins

Metalloporphyrins with open d-shell ions can drive biochemical energy cycles. However, their utilization in photoconversion is hampered by rapid deactivation. Mapping the relaxation pathways is essential for elaborating strategies that can favorably alter the charge dynamics through chemical design and photoexcitation conditions. Here, we combine transient optical absorption spectroscopy and transient X-ray emission spectroscopy with femtosecond resolution to probe directly the coupled electronic and spin dynamics within a photoexcited nickel porphyrin in solution. Measurements and calculations reveal that a state with charge-transfer character mediates the formation of the thermalized excited state, thereby advancing the description of the photocycle for this important representative molecule. More generally, establishing that intramolecular charge-transfer steps play a role in the photoinduced dynamics of metalloporphyrins with open d-shell sets a conceptual ground for their development as building blocks capable of boosting nonadiabatic photoconversion in functional architectures through "hot" charge transfer down to the attosecond time scale.

Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

A hair-ball heterostructure of MnS-MnS2/CdS with compact linking interface for ultrasensitive photoelectrochemical bioanalysis of carcinoembryonic antigen

The heterostructured photoelectric material is supposed to markedly promote the photoelectrochemical (PEC) property. Herein, the species heterostructured MnS/CdS and MnS-MnS2/CdS(1∼2) composites derived from Mn-ZIF MOFs via a sulfofication reaction using Cd(NO3)2, CdC12 cadmium source, respectively. Under irradiation, the PEC tests showed that the photocurrent response of MnS-MnS2/CdS(1∼2) signally enhanced compared to globose MnS/CdS heterostructure and pure MnS or CdS. It was ascribed to the matching band-gap to form type II heterojunction in MnS-MnS2/CdS(1∼2) which dramatically facilitated photo-induced electron/hole (e-/h+) separation and transfer. The hair-ball morphologies structure of MnS-MnS2/CdS(1∼2) with large number of pores was beneficial to improve penetrating efficiency of the electrolyte liquid. Meanwhile, the well-synergistic effect on the MnS, MnS2, CdS components and with tight connecting heterojunction interface among MnS-MnS2/CdS(1∼2) which also led to violently photocurrent output. Besides, the chitosan (CS) was covalently coupled with glutaraldehyde (GLD) to obtain steady composite film, and the cross-linker of GLD can achieve the high efficiency to graft the Apt-CEA (aptamer) biomolecules, which resulting in the promotion of hybridization reaction efficiency of the CEA target. Hence, this created biosensor of Apt-CEA/GLD-CS/MnS-MnS2/CdS(1)/ITO for the CEA detection displayed a wide linear range from 0.001 to 18 ng mL-1 and with ultralow detection limit of 0.313 pg mL-1. This research innovatively prepared a contact heterojunction interface with special porosities structure, which had superior PEC nature for the fabrication of high-performance biosensor.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

A novel central seven-membered BOPYOs: Synthesis, optical properities and optimization of BF2 removal

Many efforts have been made to enrich the variety of BF2 complexes because of their excellent optical properties. However, the investigation on seven-membered ring N, O-chelated BF2 complexes is rare due to their instability with the removal of BF2 unit. Herein, a novel seven-membered ring N, O-chelated BF2 complexes (BOPYOs) with dual-state emission has been synthesized via a facile method. The results of optical properties showed that the fluorescence quantum yield of BOPYO-2 with donor group on 1 and 2-position of 1-indanone unit is much higher than that of BOPYO-1, 3-5 in toluene. The emission spectra of BOPYO-6 or 7 have redshift phenomenon compared with BOPYO-1-5 with weak fluorescence intensity due to their highly distorted structure or intramolecular charge transfer (ICT) effect. BOPYOs show relatively moderate solid emission from orange to deep red color with 596 nm to 686 nm. On the contrary, fluorescence quantum yield of BOPYO-2 in solid is the lowest. The optical properties in solution and solid states are further supported by the single-crystal structure and DFT calculation. Furthermore, the investigation on optimization of BF2 removal shows that the corresponding precursors of BOPYOs could be obtained in protic solvents without adding other catalysts.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

TRANSCRIPTOME ANALYSIS REVEALED THE MOLECULAR SIGNATURES OF CISPLATIN-FLUOROURACIL COMBINED CHEMOTHERAPY RESISTANCE IN GASTRIC CANCER

Gastric cancer (GC) is among the top five malignant tumors worldwide in terms of morbidity and death. Chemotherapy is the primary treatment for unresectable or advanced postoperative GC. Chemotherapy resistance developed against cisplatin-fluorouracil (CF) combined chemotherapy is one of the most common clinical issues in patients with GC, leading to poor prognosis. Two different methods were used to analyze GSE14210, and two gene sets were obtained. The first method involved performing the traditional difference analysis (adjusted p<0.05, |log2FC|>=1) by Network Analyst to obtain gene set 1, followed by conducting gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis on the obtained gene set. The second method involved using iDEP to make the weighted gene co-expression network analysis (WGCNA) and performing GO and KEGG enrichment analysis, to obtain gene set 2. Thereafter, the STRING database and Cytoscape were used to construct Protein-Protein Interaction (PPI) networks, screen core clusters, and hub genes of the two gene sets. Furthermore, the hub genes were verified in GSE14210 by the survival analysis method of the Kaplan-Meier plotter database. Finally, we analyzed the mRNA expression of the hub genes by UALCAN and the protein expression of the same by Human Protein Atlas (HPA). Three real hub genes with the same mRNA expression as that of protein were identified, including CENPB, MTA1, and GCNT3. Finally, we performed single gene GO and KEGG enrichment analyses to explore the possible mechanisms of action of these three genes. The mRNA and protein expressions of CENPB, MTA1, and GCNT3 were upregulated in CF-resistant GC patients, and they were significantly associated with bad overall survival (OS). CENPB, MTA1 and GCNT3 are expected to be biomarkers with promising clinical applications as potential therapeutic targets for patients with refractory GC treated with CF combined chemotherapy.

Insights into the Growth of Ternary WSSe Nanotubes in an Atmospheric CVD Reactor

The synthesis of complex new nanostructures is challenging but also bears the potential for observing new physiochemical properties and offers unique applications in the long run. High-temperature synthesis of ternary WSe2xS2(1-x) (denoted as WSSe) nanotubes in a pure phase and in substantial quantities is particularly challenging, requiring a unique reactor design and control over several parameters, simultaneously. Here, the growth of WSSe nanotubes with the composition 0 ≤ x < 1 from W18O49 nanowhiskers in an atmospheric chemical vapor deposition (CVD) flow reactor is investigated. The oxide precursor powder is found to be heavily agglomerated, with long nanowhiskers decorating the outer surface of the agglomerates and their core being enriched with oxide microcrystallites. The reaction kinetics with respect to the chalcogen vapors varies substantially between the two kinds of oxide morphologies. Insights into the chemical reactivity and diffusion kinetics of S and Se within W18O49 nanowhishkers and the micro-oxide crystallites were gained through detailed microscopic, spectroscopic analysis of the reaction products and also through density functional theory (DFT) calculations. For safety reasons, the reaction duration was limited to half an hour each. Under these circumstances, the reaction was completed for some 50% of the nanotubes and the other half remained with thick oxide core producing new WOx@WSSe core-shell nanotubes. Furthermore, the selenium reacted rather slowly with the WOx nanowhiskers, whereas the more ionic and smaller sulfur atoms were shown to diffuse and react faster. The yield of the combined hollow and core-shell nanotubes on the periphery of the agglomerated oxide was very high, approaching 100% in parts of the reactor boat. The nanotubes were found to be very thin (∼80% with a diameter <40 nm). The optical properties of the nanotubes were studied, and almost linear bandgap modulation was observed with respect to the selenium content in the nanotubes. This investigation paves the way for further scaling up the synthesis and for a detailed study of the different properties of WSSe nanotubes.

Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

[The impact of extended waiting time on tumor regression after neoadjuvant chemoradiotherapy for locally advanced rectal cancer]

Objective: To investigate the influence of extending the waiting time on tumor regression after neoadjuvant chemoradiology (nCRT) in patients with locally advanced rectal cancer (LARC). Methods: Clinicopathological data from 728 LARC patients who completed nCRT treatment at the First Affiliated Hospital, Naval Medical University from January 2012 to December 2021 were collected for retrospective analysis. The primary research endpoint was the sustained complete response (SCR). There were 498 males and 230 females, with an age (M(IQR)) of 58 (15) years (range: 22 to 89 years). Logistic regression models were used to explore whether waiting time was an independent factor affecting SCR. Curve fitting was used to represent the relationship between the cumulative occurrence rate of SCR and the waiting time. The patients were divided into a conventional waiting time group (4 to <12 weeks, n=581) and an extended waiting time group (12 to<20 weeks, n=147). Comparisons regarding tumor regression, organ preservation, and surgical conditions between the two groups were made using the t test, Wilcoxon rank sum test, or χ2 test as appropriate. The Log-rank test was used to elucidate the survival discrepancies between the two groups. Results: The SCR rate of all patients was 21.6% (157/728). The waiting time was an independent influencing factor for SCR, with each additional day corresponding to an OR value of 1.010 (95%CI: 1.001 to 1.020, P=0.031). The cumulative rate of SCR occurrence gradually increased with the extension of waiting time, with the fastest increase between the 10th week. The SCR rate in the extended waiting time group was higher (27.9%(41/147) vs. 20.0%(116/581), χ2=3.901, P=0.048), and the organ preservation rate during the follow-up period was higher (21.1%(31/147) vs. 10.7%(62/581), χ2=10.510, P=0.001). The 3-year local recurrence/regrowth-free survival rates were 94.0% and 91.1%, the 3-year disease-free survival rates were 76.6% and 75.4%, and the 3-year overall survival rates were 95.6% and 92.2% for the conventional and extended waiting time groups, respectively, with no statistical differences in local recurrence/regrowth-free survival, disease-free survival and overall survival between the two groups (χ2=1.878, P=0.171; χ2=0.078, P=0.780; χ2=1.265, P=0.261). Conclusions: An extended waiting time is conducive to tumor regression, and extending the waiting time to 12 to <20 weeks after nCRT can improve the SCR rate and organ preservation rate, without increasing the difficulty of surgery or altering the oncological outcomes of patients.

Nature of Self-Trapped Exciton Emission in Zero-Dimensional Cs2ZrCl6 Perovskite Nanocrystals

Low dimensional perovskite-inspired materials with self-tapped exciton (STE) emission have stimulated a surge of cutting-edge research in optoelectronics. Despite numerous efforts on developing versatile low-dimensional perovskite-inspired materials with efficient STE emissions, there is little emphasis on the intrinsic dynamics of STE-based broad emission in these materials. Here, we investigated the excited state dynamics in zero-dimensional (0D) Cs2ZrCl6 nanocrystals (NCs) with efficient blue STE emission. By using femtosecond transient absorption (fs-TA) spectroscopy, the ultrafast STE formation process within 400 fs is directly observed. Then, the formed STEs relax to an intermediate STE state with a lifetime of ∼180 ps before reaching the emissive STE state with a lifetime of ∼15 μs. Our work offers a comprehensive and precise dynamic picture of STE emission in low-dimensional metal halides and sheds light on extending their potential applications.

Ultrafast Jahn-Teller Photoswitching in Cobalt Single-Ion Magnets

Single-ion magnets (SIMs) constitute the ultimate size limit in the quest for miniaturizing magnetic materials. Several bottlenecks currently hindering breakthroughs in quantum information and communication technologies could be alleviated by new generations of SIMs displaying multifunctionality. Here, ultrafast optical absorption spectroscopy and X-ray emission spectroscopy are employed to track the photoinduced spin-state switching of the prototypical complex [Co(terpy)2 ]2+ (terpy = 2,2':6',2″-terpyridine) in solution phase. The combined measurements and their analysis supported by density functional theory (DFT), time-dependent-DFT (TD-DFT) and multireference quantum chemistry calculations reveal that the complex undergoes a spin-state transition from a tetragonally elongated doublet state to a tetragonally compressed quartet state on the femtosecond timescale, i.e., it sustains ultrafast Jahn-Teller (JT) photoswitching between two different spin multiplicities. Adding new Co-based complexes as possible contenders in the search for JT photoswitching SIMs will greatly widen the possibilities for implementing magnetic multifunctionality and eventually controlling ultrafast magnetization with optical photons.

Localized Bound Multiexcitons in Engineered Quasi-2D Perovskites Grains at Room Temperature for Efficient Lasers

Reducing the excitation threshold to minimize the Joule heating is critical for the realization of perovskite laser diodes. Although bound excitons are promising for low threshold laser, how to generate them at room temperature for laser applications is still unclear in quasi-2D perovskite-based devices. In this work, via engineering quasi-2D perovskite PEA₂ (CH₃ NH₃ )_{n -1} Pb_n Br_{3 n +1} microscopic grains by the anti-solvent method, room-temperature multiexciton radiative recombination is successfully demonstrated at a remarkably low pump density of 0.97 µJ cm^-2 , which is only one-fourth of that required in 2D CdSe nanosheets. In addition, the well-defined translational momentum in quasi-2D perovskite grains can restrict the Auger recombination which is detrimental to radiative emission. Furthermore, the quasi-2D perovskite grains are favorable for increasing binding energies of excitons and biexcitons and so as the related radiative recombination. Consequently, the prepared <n = 8> phase quasi-2D perovskite film renders a threshold of room-temperature stimulated emission as low as 13.7 µJ cm^-2 , reduced by 58.6% relative to the amorphous counterpart with larger grains. The findings in this work are expected to facilitate the development of solution-processable perovskite multiexcitonic laser diodes.

Chito-oligosaccharides and macrophages have synergistic effects on improving ovarian stem cells function by regulating inflammatory factors

BACKGROUND

Chronic low-grade inflammation and ovarian germline stem cells (OGSCs) aging are important reasons for the decline of ovarian reserve function, resulting in ovarian aging and infertility. Regulation of chronic inflammation is expected to promote the proliferation and differentiation of OGSCs, which will become a key means for maintaining and remodeling ovarian function. Our previous study demonstrated that Chitosan Oligosaccharides (Cos) promoted the OGSCs proliferation and remodelled the ovarian function through improving the secretion of immune related factors,but the mechanism remains unclear, and the role of macrophages, the important source of various inflammatory mediators in the ovary needs to be further studied. In this study, we used the method of macrophages and OGSCs co-culture to observe the effect and mechanism of Cos on OGSCs, and explore what contribution macrophages give during this process. Our finding provides new drug treatment options and methods for the prevention and treatment of premature ovarian failure and infertility.

METHODS

We used the method of macrophages and OGSCs co-culture to observe the effect and mechanism of Cos on OGSCs, and explore the important contribution of macrophages in it. The immunohistochemical staining was used to locate the OGSCs in the mouse ovary. Immunofluorescent staining, RT-qPCR and ALP staining were used to identify the OGSCs. CCK-8 and western blot were used to evaluate the OGSCs proliferation. β-galactosidase(SA-β-Gal) staining and western blot were used to detect the changing of cyclin-dependent kinase inhibitor 1A(P21), P53, Recombinant Sirtuin 1(SIRT1) and Recombinant Sirtuin 3(SIRT3). The levels of immune factors IL-2, IL-10, TNF-α and TGF-β were explored by using Western blot and ELISA.

RESULTS

We found that Cos promoted OGSCs proliferation in a dose-and time-dependent manner, accompanied by IL-2, TNF-α increase and IL-10, TGF-β decrease. Mouse monocyte-macrophages Leukemia cells(RAW) can also produce the same effect as Cos. When combined with Cos, it can enhance the proliferative effect of Cos in OGSCs, and further increase IL-2, TNF-α and further decrease IL-10, TGF-β. The macrophages can enhance the proliferative effect of Cos in OGSCs is also associated with the further increase in IL-2, TNF-α and the further decrease in IL-10, TGF-β. In this study, we determined that the anti-aging genes SIRT-1 and SIRT-3 protein levels were increased by Cos and RAW respectively, whereas the senescence-associated SA-β-Gal and aging genes P21 and P53 were decreased. Cos and RAW had a protective effect on OGSCs delaying aging. Furthermore, RAW can further decrease the SA-β-Gal and aging genes P21 and P53 by Cos, and further increase SIRT1 and SIRT3 protein levels in OGSCs by Cos.

CONCLUSION

In conclusion, Cos and macrophages have synergistic effects on improving OGSCs function and delaying ovarian aging by regulating inflammatory factors.

[Advances in tumor regression patterns and safe distance of distal resection margin after neoadjuvant therapy for rectal cancer]

Neoadjuvant therapy has been widely applied in the treatment of rectal cancer, which can shrink tumor size, lower tumor staging and improve the prognosis. It has been the standard preoperative treatment for patients with locally advanced rectal cancer. The efficacy of neoadjuvant therapy for rectal cancer patients varies between individuals, and the results of tumor regression are obviously different. Some patients with good tumor regression even achieve pathological complete response (pCR). Tumor regression is of great significance for the selection of surgical regimes and the determination of distal resection margin. However, few studies focus on tumor regression patterns. Controversies on the safe distance of distal resection margin after neoadjuvant treatment still exist. Therefore, based on the current research progress, this review summarized the main tumor regression patterns after neoadjuvant therapy for rectal cancer, and classified them into three types: tumor shrinkage, tumor fragmentation, and mucin pool formation. And macroscopic regression and microscopic regression of tumors were compared to describe the phenomenon of non-synchronous regression. Then, the safety of non-surgical treatment for patients with clinical complete response (cCR) was analyzed to elaborate the necessity of surgical treatment. Finally, the review studied the safe surgical resection range to explore the safe distance of distal resection margin.

A156 OUTCOMES FOLLOWING ENDOSCOPIC RESECTION OF GASTRIC NEUROENDOCRINE TUMOURS FROM A TERTIARY-CARE ACADEMIC CENTRE

Background

Gastric neuroendocrine tumours (G-NET) are rare cancers derived from neuroendocrine cells of the stomach. A steady increase in the incidence of these tumours has been observed. Current treatment and surveillance strategies are guided by various tumour characteristics including size, grade, and depth of invasion. There exists conflicting evidence, however, on the rates of recurrence from positive resection margins following primary endoscopic resection. Thus, it remains uncertain whether complete endoscopic resection (R0) of these indolent tumours is clinically significant and whether follow-up endoscopic or surgical intervention is justified.

Purpose

Our aim is to characterize current management patterns and clinical outcomes in patients undergoing endoscopic resection of G-NETs.

Method

We conducted a retrospective, single-centre cohort study at The Centre for Advanced Therapeutic Endoscopy and Endoscopic Oncology at St. Michael’s Hospital, Toronto, Ontario. Consecutive patients over the age of 18 who underwent endoscopic resection of histologically proven G-NETs between 2011 and 2020 were included. Data on patient, endoscopic, and tumour characteristics were collected through electronic chart review. Descriptive statistics were conducted for data analysis.

Result(s)

A total of 155 foregut neuroendocrine tumours were endoscopically resected during the study period, of which 108 were identified as G-NETs. 95.3% were classified as Type I. Mean tumour size was 8.93 ± 5.27 mm. Cap-assisted EMR was performed most frequently (n=51), followed by conventional EMR (n=35). ESD was performed in eight cases. Seven intra-procedural perforations occurred, of which all were closed endoscopically. One patient experienced post-procedural perforation requiring ICU and surgery. Positive resection margins (R1) were found in 25% of cases (n=27), of which 78% were assessed at surveillance endoscopy 1 (SE1). Six patients with R1 margins were referred for surgical evaluation and four were lost to follow-up. 78% of all resected G-NETs were followed at SE1 with a median interval of 196 days (range, 23 to 3373). SE1 recurrence rate at the primary resection site was 14% (n=12), of which two were from routine scar biopsies in the absence of endoscopically identifiable recurrence. All visible recurrences at these sites (n=10) were managed with repeat endoscopic resection. Patient and tumour characteristics in the evaluation of G-NET recurrence are presented in Table I.

Image

Conclusion(s)

G-NET recurrence occurs in less than 15% of patients at surveillance endoscopy following endoscopic resection in spite of a predictably higher R1 resection rate. Patient, endoscopic, and tumour factors including method of resection and margin status do not appear to impact the development of early recurrence. Given the indolent nature of these tumours, patients with positive resection margins can be followed conservatively. Further investigation is warranted to determine the optimal duration and surveillance strategy for these patients.

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Disclosure of Interest

None Declared

A155 OUTCOMES FOLLOWING ENDOSCOPIC RESECTION OF DUODENAL NEUROENDOCRINE TUMOURS FROM A TERTIARY-CARE ACADEMIC CENTRE

Background

Duodenal neuroendocrine tumours (D-NET) are rare cancers derived from neuroendocrine cells of the duodenum. A steady increase in the incidence of these tumours has been observed. Current treatment and surveillance strategies are guided by various tumour characteristics including size, grade, and depth of invasion. There exists conflicting evidence, however, on the rates of recurrence after positive resection margins following endoscopic resection. Thus, it remains uncertain whether complete endoscopic resection (R0) of these indolent tumours is clinically significant and whether follow-up endoscopic or surgical intervention is justified.

Purpose

Our aim is to characterize endoscopic management and clinical outcomes in patients undergoing endoscopic resection of D-NETs.

Method

We conducted a retrospective, single-centre cohort study at The Centre for Advanced Therapeutic Endoscopy and Endoscopic Oncology at St. Michael’s Hospital, Toronto, Ontario. Consecutive patients over the age of 18 who underwent endoscopic resection of histologically proven D-NETs between 2011 and 2020 were included. Data on patient, endoscopic, and tumour characteristics were collected through electronic chart review. Descriptive statistics were conducted for data analysis.

Result(s)

A total of 155 foregut neuroendocrine tumours (NET) were endoscopically resected amongst 96 patients during the study period. 47 of these were histologically identified as D-NETs. Mean tumour size was 9.88 ± 6.86 mm. Conventional endoscopic mucosal resection (EMR) was performed most frequently (55%, n=26/47), followed by cap-assisted EMR (30%, n=14/47). Hybrid endoscopic submucosal dissection (ESD)/EMR was performed in one case. A total of two intra-procedural perforations occurred, both of which were successfully closed endoscopically. One patient with a peri-ampullary D-NET experienced significant intra-procedural bleeding requiring Hemospray® and subsequent endotracheal intubation resulting in a brief hospitalization. 57% of all resected D-NETs were followed at surveillance endoscopy 1 (SE1) at a median interval of 199 days (range, 84 to 830). Positive resection margins (R1) were found in 26 cases (55%), of which 16 were assessed at SE1 while nine were lost to follow-up. One patient with R1 margins was electively treated with APC at SE1. Tumour recurrence at SE1 occurred in only two patients.

Image

Conclusion(s)

D-NET recurrence is found in less than 5% of patients at surveillance endoscopy following endoscopic resection in spite of a high R1 resection rate. Given this indolent nature of these tumours, our study suggests that patients with positive resection margins can be followed conservatively with surveillance endoscopy. Further investigation is warranted to determine the optimal duration and surveillance strategy for these patients.

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CAG

Disclosure of Interest

None Declared

A42 LIVE DONOR LIVER TRANSPLANTATION IN PRIMARY SCLEROSING CHOLANGITIS: AN INDICATOR OF AN ORGAN ALLOCATION SYSTEM NOT ADDRESSING PATIENT NEED

Background

Liver transplantation is frequently lifesaving for people living with primary sclerosing cholangitis (PSC). However, patients are waitlisted for liver transplant (LT) according to the MELD-Na score, which may not accurately reflect the burden of living with PSC.

Purpose

We sought to describe and analyze the clinical trajectory for patients with PSC referred for LT, in a mixed deceased donor/live donor transplant programme.

Method

This was a retrospective cohort study from November 2012 to December 2019 including all patients with PSC referred for assessment at the University Health Network Liver Transplant Clinic. Patients who required multiorgan transplant or re-transplantation were excluded. Liver symptoms, hepatobiliary malignancy, MELD-Na progression, and death were abstracted from chart review. Competing Risk analysis was used for timing of LT, transplant type, and death.

Result(s)

Of 172 PSC patients assessed, 144 (84%) were listed, of whom 106/144 (74%) were transplanted. Mean age was 47.6 years and 66% were male. During follow-up through to 2021, 23/144 (16%) were removed from the waitlist due to infection, clinical deterioration, liver-related mortality or new cancer; 3 had clinical improvement. At the time of listing, 118/144 (81.95%) had a potential Living Donor (pLD) of whom 94 were transplanted: 64 live donor and 30 deceased donor. Patients with pLD had 79% lower mortality (p<0.001), and higher rates of transplantation (80% vs 46%). Exception points were granted to 13/172 (7.5%) patients.

Conclusion(s)

In a high-volume North American liver transplant centre, most patients with PSC assessed for transplant were listed and subsequently transplanted. However, this was a consequence of patients engaging in live donor transplantation. Our findings support the concern from patients with PSC that MELD-Na allocation does not adequately address their needs.

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CIHR, Other

Please indicate your source of funding;

This study was supported by PSC Partners Canada, Canadian Institutes of Health Research (CIHR), Toronto General and Western Hospital Foundation.

Disclosure of Interest

None Declared

Expression and function of patatin-like phospholipase domain-containing 2 in cleft palate induced by retinoic acid

Cleft palate is a common maxillofacial congenital malformation, and its mechanism still has not been fully illustrated. Recently, lipid metabolic defects have been observed in cleft palate. Patatin-like phospholipase domain-containing 2 (Pnpla2) is an important lipolytic gene. However, its effect on the formation of cleft palate remains unknown. In this research, we explored the expression of Pnpla2 in the palatal shelves of control mice. We also studied mice with cleft palates induced by retinoic acid and its effect on the embryonic palatal mesenchyme (EPM) cells phenotype. We found that Pnpla2 was expressed in the palatal shelves of both the cleft palate and control mice. Pnpla2 expression was lower in cleft palate mice than in the control mice. Experiments with EPM cells showed that knockdown of Pnpla2 inhibited cell proliferation and migration. In conclusion, Pnpla2 is linked to palatal development. We have indicated that low expression of Pnpla2 affects palatogenesis by inhibiting the proliferation and migration of EPM cells.

Facile Synthesis of Tetraphenylethene (TPE)-Based Fluorophores Derived by π-Extended Systems: Opposite Mechanofluorochromism, Anti-Counterfeiting and Bioimaging

Although remarkable progresses are achieved in the design and development of the mono-shift in photoluminescence for mechanofluorochromic materials, it is still a severe challenge to explore the opposite mechanofluorochromic materials with both blue- and red-shifted photoluminescence. Herein, two unprecedented 4,5-bis(TPE)-1H-imidazole fused pyridine or quinoline-based fluorophores X-1 and X-2 were designed and synthesized, and X-1 and X-2, exhibit completely opposite mechanofluorochromic behavior. Under UV lamp, the color of pristine X-1 changed from blue to green with reversible redshifted 27 nm in fluorescence emission spectra after ground, while the color of pristine X-2 changed from red to yellow with reversible blue-shifted 74 nm after ground. The detailed characterizations (including PXRD, SEM and DSC) confirmed that this opposite mechanofluorochromism was attributed to the transformation of order-crystalline and amorphous states. The crystal structure analysis and theoretical calculation further explain that opposite mechanofluorochromic behavior take into account different π-π stacking mode by induced π-extended systems. In addition, these TPE-based fluorophores (X-1 and X-2) exhibited excellent bio-compatibility and fluorescence properties for bio-imaging, writable data storage and anti-counterfeiting materials.

Slower Auger Recombination in 12-Faceted Dodecahedron CsPbBr3 Nanocrystals

Over the past two decades, intensive research efforts have been devoted to suppressions of Auger recombination in metal-chalcogenide and perovskite nanocrystals (PNCs) for the application of photovoltaics and light emitting devices (LEDs). Here, we have explored dodecahedron cesium lead bromide perovskite nanocrystals (DNCs), which show slower Auger recombination time compared to hexahedron nanocrystals (HNCs). We investigate many-body interactions that are manifested under high excitation flux density in both NCs using ultrafast spectroscopic pump-probe measurements. We demonstrate that the Auger recombination rate due to multiexciton recombinations are lower in DNCs than in HNCs. At low and intermediate excitation density, the majority of carriers recombine through biexcitonic recombination. However, at high excitation density (>10¹⁸ cm^-3) a higher number of many-body Auger process dominates over biexcitonic recombination. Compared to HNCs, high PLQY and slower Auger recombinations in DNCs are likely to be significant for the fabrication of highly efficient perovskite-based photonics and LEDs.

Fructose Consumption is Associated with a Higher Risk of Dementia and Alzheimer's Disease: A Prospective Cohort Study

BACKGROUND

This study aimed to investigate the association between fructose consumption and all-cause dementia, and Alzheimer's disease (AD) dementia.

METHODS

We used data from the Framingham Offspring Study (FOS) Cohort exams 5 through 9. Fructose consumption was quantified using a food-frequency questionnaire (FFQ) at cohort examinations 5 and participants were dementia-free at baseline. Surveillance for incident events commenced at examination 9 through 2014. Multivariable Cox proportional hazards regression was used to estimate the hazard ratios for the association between fructose consumption and incidence of all-cause dementia and AD dementia.

RESULTS

Over a mean follow-up of 15.2 (interquartile range, 12.3-17.1) years (31715.1 person-years), there were 233 dementia events of which 163 were AD dementia (70.0%). After multivariate adjustments, individuals with the highest consumption of fructose had a higher risk of all-cause dementia, and AD dementia when comparing daily cumulative consumption to 0 per week (reference), with HRs of 1.49 (95% 1.14-1.84, P for trend < 0.001) for all-cause dementia, and 1.60 (95%CI 1.22-2.01, P-trend < 0.001) for AD dementia. And the comparable results were shown in the subgroups for individuals with median consumption of fructose.

CONCLUSION

Fructose consumption was associated with a higher risk of all-cause dementia and AD dementia.

Highly Efficient and Ultralong Afterglow Emission with Anti-Thermal Quenching from CsCdCl3 : Mn Perovskite Single Crystals

Triplet exciton-based long-lived phosphorescence is severely limited by the thermal quenching at high temperature. Herein, we propose a novel strategy based on the energy transfer from triplet self-trapped excitons to Mn²⁺ dopants in solution-processed perovskite CsCdCl₃ . It is found the Mn²⁺ doped hexagonal phase CsCdCl₃ could simultaneously exhibit high emission efficiency (81.5 %) and long afterglow duration time (150 s). Besides, the afterglow emission exhibits anti-thermal quenching from 300 to 400 K. In-depth charge-carrier dynamics studies and density functional theory (DFT) calculation provide unambiguous evidence that carrier detrapping from trap states (mainly induced by Cl vacancy) to localized emission centers ([MnCl₆ ]^4- ) is responsible for the afterglow emission with anti-thermal quenching. Enlightened by the present results, we demonstrate the application of the developed materials for optical storage and logic operation applications.

Direct Observation of Size-Dependent Phase Transition in Methylammonium Lead Bromide Perovskite Microcrystals and Nanocrystals

Methylammonium (MA) lead halide perovskites have been widely studied as active materials for advanced optoelectronics. As crystalline semiconductor materials, their properties are strongly affected by their crystal structure. Depending on their applications, the size of MA lead halide perovskite crystals varies by several orders of magnitude. The particle size can lead to different structural phase transitions and optoelectronic properties. Herein, we investigate the size effect for phase transition of MA lead bromide (MAPbBr₃) by comparing the temperature-dependent neutron powder diffraction patterns of microcrystals and nanocrystals. The orthorhombic-to-tetragonal phase transition occurs in MAPbBr₃ microcrystals within the temperature range from 100 to 310 K. However, the phase transition is absent in nanocrystals in this temperature range. In this work, we offer a persuasive and direct evidence of the relationship between the particle size and the phase transition in perovskite crystals.

Beating signals in CdSe quantum dots measured by low-temperature 2D spectroscopy

Advances in ultrafast spectroscopy can provide access to dynamics involving nontrivial quantum correlations and their evolutions. In coherent 2D spectroscopy, the oscillatory time dependence of a signal is a signature of such quantum dynamics. Here we study such beating signals in electronic coherent 2D spectroscopy of CdSe quantum dots (CdSe QDs) at 77 K. The beating signals are analyzed in terms of their positive and negative Fourier components. We conclude that the beatings originate from coherent LO-phonons of CdSe QDs. No evidence for the quantum dot size dependence of the LO-phonon frequency was identified.

Inhibition of novel lipoprotein(a) receptor major facilitator superfamily domain containing 5 (MFSD5) reduces development of aortic valve calcification

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Private grant from Kowa Pharmaceuticals to Brigham and Woman's Hospital

Calcific aortic valve stenosis (CAVS) is the most prevent valvular heart disease in the western world increasing exponentially with age, with an 112% increase in CAVS deaths in the last three decades; however no therapeutic treatment is currently available. Recently, lipoprotein(a) [Lp(a)] has been demonstrated to be an independent and causal risk factor for CAVS, yet the understanding of its cellular uptake and catabolism is limited thus underscoring the need for further investigation.

This study aimed to determine a target receptor, unique for Lp(a) on the surface of valvular interstitial cells (VICs) and ascertain the role of the receptor on the development of VIC calcification.

Unbiased ligand-receptor capture mass spectrometry (TriCEPS) was used to identify target receptor, with western blotting, ELISA, qPCR, alizarin red calcium staining and immunofluorescence used to validate the targets in vitro via siRNA inhibition and overexpression. Transmission electron microscopy (TEM) was used to determine uptake of Lp(a) within excised human valves. Identification of small molecule inhibitors was assessed computationally via the L1000 dataset, with the top hit candidate validated in vitro. Genotype-phenotype studies were examined using the United Kingdom Biobank (UKBB) and the Millions Veterans Program. Linear regression was used to evaluate association between aortic stenosis and plasma Lp(a) levels, and a phenotype-wide association analysis was then performed against this generated ‘genotype’.

Ligand-receptor capture mass spectrometry was used to detect novel membrane proteins with specific binding to Lp(a); MFSD5, MRC2, LDLR were identified as possible candidates. MFSD5 RNAscope demonstrated its presence in human aortic valves. Lp(a) uptake in VICs was confirmed via western blot and TEM. MFSD5 siRNA significantly reduced dil-labelled Lp(a) uptake in human VICs (p=0.003) and HEPG2 cells (p=0.0003), conversely MFSD5 overexpression increased uptake (p=0.0345, p=0.0318), whilst specificity of MFSD5 to Lp(a) alone was shown via no change in LDL uptake following MFSD5 inhibition (p=0.616, p=0.991). MFSD5 inhibition reduced RUNX2 (p=0.0124) and Osteocalcin (p&lt;0.001) RNA expression and reduced alizarin red staining following culture in Lp(a) osteogenic media for 21 days (p&lt;0.0033). Druggability of MFSD5 was confirmed by the L1000 database, which identified aminopurvalanol as a binding partner for MFSD5 and significantly reduced Lp(a) uptake within VICs (p=0.0091). MFSD5-loss of function within the UKBB showed no significant cardiovascular association, however 50kb +/- of the MFSD5 gene showed nominal association with hyperlipidaemia and atrial fibrillation.

The current study demonstrates the novel Lp(a) receptor MFSD5 may be responsible for uptake of Lp(a) within VICs, resulting in the development of aortic valve calcification, highlighting the need for further exploration into the role of MFSD5 in aortic valve disease.

Morphology-Dependent One- and Two-Photon Absorption Properties in Blue Emitting CsPbBr3 Nanocrystals

The linear and nonlinear optical parameters and morphologic dependence of CsPbBr₃ nanocrystals (NCs) are crucial for device engineering. In particular, such information in asymmetric nanocrystals is still insufficient. We characterized the OPLA (σ¹) and TPA cross sections (σ²) of a series CsPbBr₃ nanocrystals with various aspect ratios (AR) using femtosecond transient absorption spectroscopy (TAS). The σ¹ presents a linear volume dependence of all the samples, which agrees with the previous behavior in CsPbBr₃ QDs. However, the σ² values do not exhibit conventional power dependency of the crystal volume but are also modulated by the shape-dependent local field factors. In addition, the local field effect in CsPbBr₃ NCs is contributed by their asymmetric morphologies and polar ionic lattices, which is more pronounced than in conventional semiconductor NCs. Finally, we revealed that the lifetimes of photogenerated multiexcitonic species of those nanocrystals feature identical morphology independence in both OPLA and TPA.

Photoinduced Polaron Formation in a Polymerized Electron-Acceptor Semiconductor

Polymerized small molecular acceptor (PSMA) based all-polymer solar cells (all-PSC) have achieved power conversion efficiencies (PCE) over 16%, and the PSMA is considered to hold great promise for further improving the performance of all-PSC. Yet, in comparison with that of the polymer donor, the photophysics of a polymerized acceptor remains poorly understood. Herein, the excited state dynamics in a polymerized acceptor PZT810 was comprehensively investigated under various pump intensities and photon energies. The excess excitation energy was found to play a key role in excitons dissociation into free polarons for neat PSMA films, while free polarons cannot be generated from the polaron pairs in neat acceptor films. This work reveals an in-depth understanding of relaxation dynamics for PSMAs and that the underlying photophysical origin of PSMA can be mediated by excitation energies and intensities. These results would benefit the realization of the working mechanism for all-PSC and the designing of new PSMAs.

Intravoxel incoherent motion diffusion-weighted imaging as a quantitative tool for evaluating disease activity in patients with axial spondyloarthritis

AIM

To determine the correlations between four quantitative magnetic resonance imaging (MRI) parameters derived from intravoxel incoherent motion diffusion-weighted images (IVIM DWI) and the semi-quantitative Spondyloarthritis Research Consortium of Canada (SPARCC) score of the sacroiliac joint (SIJ) and five clinical activity indices in patients with axial spondyloarthritis (axSpA).

AND METHODS

A total of 75 patients with axSpA and complete clinical activity indices and SIJ MRI were enrolled to this prospective study. Univariable and multivariable linear regression analyses were performed to evaluate correlations between MRI parameters and clinical activity indices after controlling for confounders. All data were further analysed using Pearson's correlation coefficients (r).

RESULTS

Only pure diffusion coefficient (D) and incoherent perfusion related microcirculation (D∗) were found to be independently positively correlated with several clinical activity indices (all p<0.05). Positive correlations were observed between D and the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Bath Ankylosing Spondylitis Functional Index (BASFI), Patient Global Assessment (PGA), extent of influence of pain, with r of 0.605, 0.402, 0.319, and 0.485 (all p<0.0125). D∗ correlated positively with BASDAI, BASFI, and PGA (r=0.436, 0.356, 0.301, respectively; all p<0.0125).

CONCLUSION

D and D∗ derived from IVIM DWI could be associated with some disease activity indices in patients with axSpA; apparent diffusion coefficient (ADC) and SPARCC scores were not correlated with these indices. IVIM DWI may be a useful tool for the quantitative assessment of disease activity in patients with axSpA.

[A descriptive analysis on type 2 diabetes in twins in China]

Objective: To describe the distribution characteristics of type 2 diabetes in twins in Chinese National Twin Registry (CNTR), provide clues and evidence for revealing the influence of genetic and environmental factors for type 2 diabetes. Methods: Of all twins registered in the CNTR during 2010-2018, a total 18 855 twin pairs aged ≥30 years with complete registration information were included in the analysis. The random effect model was used to describe the population and area distribution characteristics and concordance of type 2 diabetes in twin pairs. Results: The mean age of the subjects was (42.8±10.2) years, the study subjects included 10 339 monozygotic (MZ) twin pairs and 8 516 dizygotic (DZ) twin pairs. The self-reported prevalence rate of type 2 diabetes was 2.2% in total population and there was no sighificant difference between MZ and DZ. Intra-twin pairs analysis showed that the concordance rate of type 2 diabetes was 38.2% in MZ twin pairs, and 16.0% in DZ twin pairs, the difference was statistically significant (P<0.001). The concordance rate of type 2 diabetes in MZ twin parts was higher than that in DZ twin pairs in both men and women, in different age groups and in different areas (P<0.05). Further stratified analysis showed that in northern China, only MZ twin pairs less than 60 years old were found to have a higher concordance rate of type 2 diabetes compared with DZ twin pairs (P<0.05). In southern China, the co-prevalence rate in male MZ twin pairs aged ≥60 years was still higher than that in DZ twin pairs (P<0.05). Conclusion: The twin pairs in this study had a lower self-reported prevalence of type 2 diabetes than the general population. The study results suggested that genetic factors play a role in type 2 diabetes prevalence in both men and women, in different age groups and in different areas, however, the effect might vary.

Visualizing Light-Induced Microstrain and Phase Transition in Lead-Free Perovskites Using Time-Resolved X-Ray Diffraction

Metal halide perovskites have emerged as promising materials for optoelectronic applications in the last decade. A large amount of effort has been made to investigate the interplay between the crystalline lattice and photoexcited charge carriers as it is vital to their optoelectronic performance. Among them, ultrafast laser spectroscopy has been intensively utilized to explore the charge carrier dynamics of perovskites, from which the local structural information can only be extracted indirectly. Here, we have applied a time-resolved X-ray diffraction technique to investigate the structural dynamics of prototypical two-dimensional lead-free halide perovskite Cs₃Bi₂Br₉ nanoparticles across temporal scales from 80 ps to microseconds. We observed a quick recoverable (a few ns) photoinduced microstrain up to 0.15% and a long existing lattice expansion (∼a few hundred nanoseconds) at mild laser fluence. Once the laser flux exceeds 1.4 mJ/cm², the microstrain saturates and the crystalline phase partially transfers into a disordered phase. This photoinduced transient structural change can recover within the nanosecond time scale. These results indicate that photoexcitation of charge carriers couples with lattice distortion, which fundamentally affects the dielectric environment and charge carrier transport.

A ratiometric fluorescent probe for sensing hypochlorite in physiological saline, bovine serum albumin and fetal bovine/calf serum

HClO/ClO^-, as one of important reactive oxygen species, is a highly reactive unavoidable by-product generated from normal cell metabolism. In recent years, efficient method for detectiing HClO/ClO^- is of great important to research its pathological or physiological function in bio-systems. In this work, we have constructed a fluorescent probe (P-Hc) with ratiometric signal for sensing HClO/ClO^- in aqueous solution, physiological saline and different serums based on 2-(benzo[d]thiazol-2-yl)phenol dye. The structure of P-Hc was characterized by NMR and HRMS spectrum. The sensing mechanism has also been verified by ¹H NMR spectrum. The P-Hc displays good sensitivity and selectivity for HClO/ClO^- with a limit of detection (LOD) of 2.03 × 10^-6 M. Furthermore, P-Hc has been applied for sensing HClO/ClO^- in physiological saline and different serums. Thus, P-Hc may provide a novel method for ratiometric fluorescent sensing HClO/ClO^- in bio-samples.

Excited States and Their Dynamics in CdSe Quantum Dots Studied by Two-Color 2D Spectroscopy

Quantum dots (QDs) form a promising family of nanomaterials for various applications in optoelectronics. Understanding the details of the excited-state dynamics in QDs is vital for optimizing their function. We apply two-color 2D electronic spectroscopy to investigate CdSe QDs at 77 K within a broad spectral range. Analysis of the electronic dynamics during the population time allows us to identify the details of the excitation pathways. The initially excited high-energy electrons relax with the time constant of 100 fs. Simultaneously, the states at the band edge rise within 700 fs. Remarkably, the excited-state absorption is rising with a very similar time constant of 700 fs. This makes us reconsider the earlier interpretation of the excited-state absorption as the signature of a long-lived trap state. Instead, we propose that this signal originates from the excitation of the electrons that have arrived in the conduction-band edge.

Optimizing the quasi-equilibrium state of hot carriers in all-inorganic lead halide perovskite nanocrystals through Mn doping: fundamental dynamics and device perspectives

Hot carrier (HC) cooling accounts for the significant energy loss in lead halide perovskite (LHP) solar cells. Here, we study HC relaxation dynamics in Mn-doped LHP CsPbI3 nanocrystals (NCs), combining transient absorption spectroscopy and density functional theory (DFT) calculations. We demonstrate that Mn2+ doping (1) enlarges the longitudinal optical (LO)-acoustic phonon bandgap, (2) enhances the electron-LO phonon coupling strength, and (3) adds HC relaxation pathways via Mn orbitals within the bands. The spectroscopic study shows that the HC cooling process is decelerated after doping under band-edge excitation due to the dominant phonon bandgap enlargement. When the excitation photon energy is larger than the optical bandgap and the Mn2+ transition gap, the doping accelerates the cooling rate owing to the dominant effect of enhanced carrier-phonon coupling and relaxation pathways. We demonstrate that such a phenomenon is optimal for the application of hot carrier solar cells. The enhanced electron-LO phonon coupling and accelerated cooling of high-temperature hot carriers efficiently establish a high-temperature thermal quasi-equilibrium where the excessive energy of the hot carriers is transferred to heat the cold carriers. On the other hand, the enlarged phononic band-gap prevents further cooling of such a quasi-equilibrium, which facilitates the energy conversion process. Our results manifest a straightforward methodology to optimize the HC dynamics for hot carrier solar cells by element doping.

Electrochemical water oxidation catalyzed by a mononuclear cobalt complex of a pentadentate ligand: the critical effect of the borate anion

A cobalt complex is found as a homogeneous water oxidation electrocatalyst. Electrochemical examinations indicate that the implementation of proton-couple electron transfer process and formation of O–O bond are assisted by borate anion.

The involvement of hormone-sensitive lipase in all-trans retinoic acid induced cleft palate

Abnormally high concentrations of all-trans retinoic acid (atRA) induce cleft palate, which is accompanied by abnormal migration and proliferation of mouse embryonic palatal mesenchyme (MEPM) cells. Hormone-sensitive lipase (HSL) is involved in many embryonic development processes. The current study was designed to elucidate the mechanism of HSL in cleft palate induced by atRA. To establish a cleft palate model in Kunming mice, pregnant mice were administered atRA (70 mg/kg) by gavage at embryonic Day 10.5 (E10.5). Embryonic palates were obtained through the dissection of pregnant mice at E15.5. Hematoxylin and eosin (H&E) staining was used to evaluate growth changes in the palatal shelves. The levels of HSL in MEPM cells were detected by immunohistochemistry, quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting. RNAi was applied to construct vectors expressing HSL small interference RNAs (siRNAs). The vectors were transfected into MEPM cells. Cell proliferation and migration were evaluated by the cell counting kit-8 (CCK-8) assay and wound healing assay, respectively. The palatal shelves in the atRA group had separated at E15.5 without fusing. In MEPM cells, the expression of HSL was reversed after atRA treatment, which caused cleft palate in vivo. In the atRA group, the proliferation of HSL siRNA-transfected cells was remarkably promoted, and the migration rate significantly increased in the HSL siRNA-transfected MEPM cells. These results suggested that HSL may be involved in cleft palate induced by atRA and that atRA enhances HSL levels to inhibit embryonic palate growth.