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In this communication, we report a new class of oscillation mode, dome-shaped mode (DSM), in liquid crystal (LC) microlasers. A record high Q-factor over 24 000 is achieved in LC soft-matter microlasers. We successfully presented a proof-of-concept demonstration of red, green, blue (RGB) LC-DSM microlaser pixels with a 74% broader achievable color gamut than the standard RGB color space. Besides, the detection limit for acetone vapor molecules is as low as 0.5 ppm, confirming the excellent potential of the proposed LC-DSM microlaser in ultra-high sensitivity detection. Agency for Science, Technology and Research (A*STAR) Published version This work is supported by A*Star-AME-IRG-A20E5c0083, NRF-CRP23-2019-0007. V. D. T. acknowledges the support from the Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.03- 2021.62. J. Y. also acknowledges the support from the National Science Fund for Distinguished Young Scholars of China (61925501), the Guangdong Introducing Innovative and Entrepreneurial Teams (2019ZT08X340) and Introducing Leading Talents (2019CX01X010) of ‘‘The Pearl River Talent Recruitment Program’’ of Guangdong Province.

Understanding the dynamical process of charge transfer (CT) across van der Waals heterostructures (VdWHs) is vitally important for improving photovoltaic conversion efficiency at the atomically thi...

Two-dimensional (2D) semiconductors have attracted great attention as a novel class of gain materials for low-threshold on-chip coherent light sources. Due to their atomically thin scale, these materials exhibit distinct gain characteristics and associated emitter-to-cavity coupling when integrated into a cavity. Despite several experimental reports on lasing, the underlying gain mechanism of 2D materials remains elusive due to a lack of key information, including modal gain and confinement factor. Here, we demonstrate a novel approach to directly determine the absorption coefficient of monolayer WS2 by characterizing the whispering gallery modes in a van der Waals microdisk cavity. By exploiting the cavity’s high intrinsic quality factor of 2.5×104, the absorption coefficient spectrum is experimentally resolved with unprecedented accuracy. We show that the excitonic gain signal and confinement factor can be assessed by analyzing the quality factors near the exciton resonance. The excitonic gain reduces the WS2 absorption coefficient by 2×104 cm− 1 at room temperature, indicating a local population inversion described in the excitonic two-band model. These results are essential for unveiling the gain mechanism in emergent low-threshold 2D-semiconductor-based laser devices.

Taking advantage of the structural characteristics of lignin-derived phenolic compounds, a combination of the Williamson and Tishchenko reactions produced a series of new α,ω-diene functionalized carboxylic ester monomers from both petrochemical and renewable resources, which were applicable in subsequent thiol–ene click and acyclic diene metathesis (ADMET) polymerizations, providing a series of poly(thioether esters) and unsaturated aromatic–aliphatic polyesters with high molecular weights.

Two α,ω-diene monomers containing a carbonate structure derived from eugenol and 2-methoxy-4-vinylphenol were successfully synthesized in high yields of 94% and 78%, respectively. With these dienes in hand, a series of poly(thioether carbonates) and unsaturated aromatic–aliphatic polycarbonates with moderate molecular weights (Mn) ranging from 17 100 to 24 400 g mol−1 and tunable thermo-properties were prepared via a thiol–ene click reaction and step growth acyclic-diene-metathesis, respectively.

We propose a deep subwavelength plasmonic cavity based on a metal-coated coaxial structure with G e 0.9 S n 0.1 as the active medium. A fundamental surface plasmon polariton mode is strongly confined on the sidewall of the metal core, with the quality factor up to 5 × 10 3 at 10 K. By reducing the cavity dimension to a few nanometers, this cavity mode shows a strong plasmon binding with the mode volume down to 8 × 10 − 10 ( λ / n ) 3 , and significant size-dependent damping caused by the non-local optical response. The Purcell factor is achieved as high as 2 × 10 9 at 10 K and 7 × 10 8 at 300 K. This cavity design provides a systematic guideline of scaling down the cavity size and enhancing the Purcell factor. Our theoretical demonstration and understanding of the subwavelength plasmonic cavity represent a significant step toward the large-scale integration of on-chip lasers with a low threshold.

This study aims to develop and validate an artificial intelligence model based on deep learning to predict early hematoma enlargement (HE) in patients with intracerebral hemorrhage. A total of 1,899 noncontrast computed tomography (NCCT) images of cerebral hemorrhage patients were retrospectively analyzed to establish a predicting model and 1,117 to validate the model. And a total of 118 patients with intracerebral hemorrhage were selected based on inclusion and exclusion criteria so as to validate the value of the model for clinical prediction. The baseline noncontrast computed tomography images within 6 h of intracerebral hemorrhage onset and the second noncontrast computed tomography performed at 24 ± 3 h from the onset were used to evaluate the prediction of intracerebral hemorrhage growth. In validation dataset 1, the AUC was 0.778 (95% CI, 0.768–0.786), the sensitivity was 0.818 (95% CI, 0.790–0.843), and the specificity was 0.601 (95% CI, 0.565–0.632). In validation dataset 2, the AUC was 0.780 (95% CI, 0.761–0.798), the sensitivity was 0.732 (95% CI, 0.682–0.788), and the specificity was 0.709 (95% CI, 0.658–0.759). The sensitivity of intracerebral hemorrhage hematoma expansion as predicted by an artificial intelligence imaging system was 89.3%, with a specificity of 77.8%, a positive predictive value of 55.6%, a negative predictive value of 95.9%, and a Yoden index of 0.671, which were much higher than those based on the manually labeled noncontrast computed tomography signs. Compared with the existing prediction methods through computed tomographic angiography (CTA) image features and noncontrast computed tomography image features analysis, the artificial intelligence model has higher specificity and sensitivity in the prediction of early hematoma enlargement in patients with intracerebral hemorrhage.

We present a novel InGaAs/InAlAs single-photon avalanche diodes array with a triple- mesa structure. High photon detection efficiency of 36% with decent dark count rate of 1.9×107 Hz is achieved at 240 K.

Background Adenosine A3 receptor (A3AR) plays a role in intestinal inflammation, but little is known about its mechnisms in intestinal inflammation such as ulcerative colitis (UC). Pyroptosis, characterized by Gasdermin D (GSDMD) activation, is implicated in the pathogenesis of UC. We investigated the role of A3AR in GSDMD-mediated pyroptosis in UC and its underlying molecular mechanisms. Methods The expression of A3AR in colonic mucosa of patients with UC were examined. A3AR agonist was used to study the role of A3AR in ex vivo colonic explants of UC patients. In addition, human intestinal epithelial cells Caco-2 were used to further verify the effect of A3AR on pyroptosis induced by LPS+ATP. RT-qPCR and western blotting were used to detect the expression levels of pyroptosis-associated factors including NLRP3, caspase-1, gasdermin-D N-terminal domain (GSDMD-NT), IL-1β and IL-18 in colonic tissues and Caco-2 cells. Immunofluorescence was used to detect the protein expression in tissues and cells. Enzyme-linked immunosorbent assay was used to determine the levels of IL-1β and IL-18 in tissue and cell culture supernatants. Lactate dehydrogenase (LDH) release assay and propidium iodide (PI) staining were used to measure cell pyroptosis. Molecular interactions beween A3AR and GSDMD were investigated using Co-IP and GST pull-down assays. Results A3AR expression was significantly reduced in colonic mucosa of patients with active UC, and colonic epithelial cells were the main cell subpopulation with down-regulated A3AR expression. Pyroptosis-associated factors, including Caspase-1, NLRP3, and GSDMD-NT, were upregulated in UC colonic tissues. The expression of A3AR and GSDMD-NT was negatively correlated. A3AR agonist reduced the production of cytokines (IL-1β and IL-18) and attenuates the expression levels of NLRP3 and GSDMD-NT in the colonic tissues of patients with UC. Furthermore, A3AR overexpression alleviated pyroptosis with reduced LDH release, PI-stained cell number and decreased expressions of GSDMD-NT, NLRP3, caspase-1, IL-1β, and IL-18 in the LPS+ATP-stimulated Caco-2 cells, whereas the opposite occurred in cells treated with small interfeing RNA (siRNA) targeting A3AR. Knockdown of GSDMD in Caco-2 cells significantly blocked the effects of A3AR overexpression or down-regulation on pyroptosis, suggesting that A3AR acts through the GSDMD-mediated pyroptosis pathway. Co-IP and GST pull-down assays showed that A3AR interacted with GSDMD. Conclusion A3AR modulates intestinal inflammation in UC through GSDMD-mediated intestinal epithelial cell pyroptosis. We propose a novel mechanism by which A3AR-GSDMD interaction affects UC through pyroptosis, suggesting that A3AR is a potential target for the treatment of UC.

There are strong interests in constructing nanolasers using two-dimensional transition metal dichalcogenides (TMDs) due to their strong light–matter interactions and high optical gain. However, most cavity designs based on transfer of exfoliated TMDs on silicon oxide are not optimized since monolayer emitters are located far from where the photonic mode reaches maximum intensity. By taking advantage of the excellent dielectric properties of hexagonal boron nitride (h-BN), we design a new microdisk optical cavity fabricated from a van der Waals (VdW) stacked h-BN/WS2/h-BN. The heterostructure is patterned into microdisk cavities characterized by whispering gallery modes (WGMs). The emission intensity of the WS2 trion is enhanced by 2.9 times that of exciton in the heterostructure, giving rise to whisper gallery modes with resonance intensities that show nonlinear power dependence. A Rayleigh scatterer directs the cavity emission to vertical collection. Such VdW heterostructure provides an atomically smooth...

The design and preparation of polymers by using biobased chemicals is regarded as an important strategy towards a sustainable polymer chemistry. Herein, two aromatic diols, 4-(hydroxymethyl)-2-methoxyphenol and 2-(4-(hydroxymethyl)-2-methoxyphenoxy)ethanol, have been prepared in good yields through the direct reduction of vanillin and hydroxyethylated vanillin (4-(2-hydroxyethoxy)-3-methoxybenzaldehyde) using NaBH4, respectively. The diols were submitted to traditional polycondensation and polyaddition with acyl chlorides and diisocyanatos, and serials of new polyesters and polyurethanes were prepared in high yields with moderate molecular weight ranging from 17,000 to 40,000 g mol&minus, 1. Their structures were characterized by 1H NMR, 13C NMR and FTIR, and their thermal properties were studied by TGA and differential scanning calorimetry (DSC), indicating that the as-prepared polyesters and polyurethanes have Tg in the range of 16.2 to 81.2 &deg, C and 11.6 to 80.4 &deg, C, respectively.

Vanillin has been regarded as one of the important biomass-based platform chemicals for aromatic polymers synthesis. Herein, novel symmetric bis(4-formyl-2-methoxyphenyl)carbonate (BFMC) and bis(4-(hydroxymethyl)-2-methoxyphenyl)carbonate (BHMC) polymeric monomers have been synthesized in high yields using vanillin as a raw chemical, which have been submitted for polymer synthesis via well-established polymeric strategies. A new class of poly(carbonate ester)s oligomers with amide moieties in their side chain can be prepared by using the BFMC as one of monomers via the Passerini three compound reaction (3CR). A new class of poly(carbonate ester)s oligomers and poly(carbonate urethane)s can be prepared via reactions between BHMC with dicarboxylic acid chlorides and diisocyanates, respectively. Their structure have been confirmed by 1H NMR, 13C NMR and FTIR, and the gel permeation chromatograph (GPC) analysis shows that the Mn of poly(carbonate ester)s oligomers ranges from 3100 to 7900 with PDI between 1.31 and 1.65, and the Mn of poly(carbonate urethane)s ranges from 16 400 to 24 400 with PDI ranging from 1.36 to 2.17. The DSC analysis shows that the poly(carbonate ester)s oligomers have relative low Tg ranging from 37.4 to 74.1 °C, and the poly(carbonate urethane)s have Tg ranging from 97.3 to 138.3 °C, mainly correlating to the structure of dicarboxylic acid chlorides and diisocyanates used.

Atomically thin molybdenum disulfide (MoS2), a direct-band-gap semiconductor, is promising for applications in electronics and optoelectronics, but the scalable synthesis of highly crystalline film remains challenging. Here we report the successful epitaxial growth of a continuous, uniform, highly crystalline monolayer MoS2 film on hexagonal boron nitride (h-BN) by molecular beam epitaxy. Atomic force microscopy and electron microscopy studies reveal that MoS2 grown on h-BN primarily consists of two types of nucleation grains (0° aligned and 60° antialigned domains). By adopting a high growth temperature and ultralow precursor flux, the formation of 60° antialigned grains is largely suppressed. The resulting perfectly aligned grains merge seamlessly into a highly crystalline film. Large-scale monolayer MoS2 film can be grown on a 2 in. h-BN/sapphire wafer, for which surface morphology and Raman mapping confirm good spatial uniformity. Our study represents a significant step in the scalable synthesis of hi...

Owing to the rapid development of data communication, there is a high demand for the large-scale integration of photonic devices into broadband communication networks. For practical integration, integrated photonic circuits are ideally fabricated on silicon platforms using processes compatible with complementary metal–oxide–semiconductor technology. Two-dimensional transition metal dichalcogenides are attractive candidates as on-chip emitters and absorbers due to their direct bandgaps, compatibility with miniaturization, large exciton binding energies, anisotropic polarizations, and strong light-matter interactions. Herein, a review of the current progress in the applications of two-dimensional materials as on-chip semiconductor devices is presented, as well as their prospects of integration on the silicon photonic platform. On-chip integrated photonic circuits are proposed based on heterostructures of hexagonal boron nitride and two-dimensional materials with functions of light sources, optical modulators, and photodetectors toward high-bandwidth optical interconnects.

Background To evaluate the feasibility and effects of recombinant tissue plasminogen activator (rt-PA) delivered by a new infusion system during endovascular intervention therapy in patients who had limb ischemia within 6 months. Methods From November 2006 to December 2010, 103 consecutive patients were randomly distributed in two groups. 10 mg (group A) and 5 mg (group B) bolus of rt-PA was respectively injected into the proximal occlusive lesion by a new infusion system. Subsequently, additional rt-PA of 10 mg (group A) and 5 mg (group B) was injected into the thrombotic occlusion, respectively. Significant underlying lesions were treated by endovascular intervention or surgery. Rates of major and minor complication, procedural success, and clinical success were evaluated statistically. Results Rates of complete lysis and partial lysis success were 12.6% (13 of 103) and 87.4% (90 of 103), respectively. To treat underlying lesions, 84.5% (84 of 103) patients received balloon angioplasty/stent implantation and 4.9% (5 of 103) patients received surgical correction. After final definitive treatment, procedural success rate was up to 99% (102 of 103) and clinical success rate was 100%. Comorbidity conditions and patient characteristics did not statistically influence the rates of success and complication. During the follow-up period of 30-day, 6-, 12- month, there was no statistical difference in the amputation-free survival rates between these two groups. Conclusion It is safe and effective to treat lower limb ischemia by combining adjunctive endovascular intervention with bolus of rt-PA (10 to 20 mg) given by a new infusion system. But long-term effects of thrombolysoangioplasty therapy in treating lower limb ischemia must be confirmed by large-scale population studies before routine use.

Huntington’s disease (HD) is a devastating neurodegenerative disease caused by the pathological elongation of the CAG repeats in the huntingtin gene. Caloric restriction (CR) has been the most reproducible environmental intervention to improve health and prolong life span. We have demonstrated that CR delayed onset and slowed disease progression in a mouse model of HD. Metformin, an antidiabetic drug, mimics CR by acting on cell metabolism at multiple levels. Long-term administration of metformin improved health and life span in mice. In this study, we showed that metformin rescued cells from mutant huntingtin (HTT)-induced toxicity, as indicated by reduced lactate dehydrogenase (LDH) release from cells and preserved ATP levels in cells expressing mutant HTT. Further mechanistic study indicated that metformin activated AMP-activated protein kinase (AMPK) and that inhibition of AMPK activation reduced its protective effects on mutant HTT toxicity, suggesting that AMPK mediates the protection of metformin in HD cells. Furthermore, metformin treatment prevented mitochondrial membrane depolarization and excess fission, and modulated the disturbed mitochondrial dynamics in HD cells. We confirmed that metformin crossed the blood-brain barrier after oral administration and activated AMPK in the mouse brain. Our results urge further evaluation of the clinical potential for use of metformin in HD treatment.

Large‐sized MoS2 crystals can be grown on SiO2/Si substrates via a two‐stage chemical vapor deposition method. The maximum size of MoS2 crystals can be up to about 305 μm. The growth method can be used to grow other transition metal dichalcogenide crystals and lateral heterojunctions. The electron mobility of the MoS2 crystals can reach ≈30 cm2 V−1 s−1, which is comparable to those of exfoliated flakes.

The role of the adenosine A3 receptor (A3AR) in experimental colitis is controversial. The A3AR agonist N6-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA) has been shown to have a clinical benefit, although studies in A3AR-deficient mice suggest a pro-inflammatory role. However, there are no studies on the effect of 2-Cl-IB-MECA and the molecular mechanism of action of A3AR in murine colitis models in vivo. Is it the same as that observed in vitro? The interaction between 2-CL-IB-MECA and A3AR in a murine colitis model and the signaling pathways associated with this interaction remain unclear. Here we demonstrate a role for the NF-κB signaling pathway and its effect on modifying the activity of proinflammatory factors in A3AR-mediated biological processes. Our results demonstrated that A3AR activation possessed marked effects on experimental colitis through the NF-κB signaling pathway.

To investigate the expression of adenosine A3 receptor (A3AR) in human colonic epithelial cells and the effects of A3AR activation on tumor necrosis factor alpha (TNF-α-) induced inflammation in order to determine its mechanism of action in human colonic epithelial cells, human colonic epithelial cells (HT-29 cells) were treated with different concentrations of 2-Cl-IB-MECA prior to TNF-αstimulation, followed by analysis of NF-κB signaling pathway activation and downstream IL-8 and IL-1βproduction. A3AR mRNA and protein were expressed in HT-29 cells and not altered by changes in TNF-αor 2-Cl-IB-MECA. Pretreatment with 2-Cl-IB-MECA prior to stimulation with TNF-αattenuated NF-κB p65 nuclear translocation as p65 protein decreased in the nucleus of cells and increased in the cytoplasm, inhibited the degradation of IκB-α, and reduced phosphorylated-IκB-αlevel significantly, compared to TNF-α-only-treated groups. Furthermore, 2-Cl-IB-MECA significantly decreased TNF-α-stimulated IL-8 and IL-1βmRNA expression and secretion, compared to the TNF-α-only treated group. These results confirm that A3AR is expressed in human colonic epithelial cells and demonstrate that its activation has an anti-inflammatory effect, through the inhibition of NF-κB signaling pathway, which leads to inhibition of downstream IL-8 and IL-1βexpression. Therefore, A3AR activation may be a potential treatment for gut inflammatory diseases such as inflammatory bowel disease.

Large-sized MoS2 crystals can be grown on SiO2/Si substrates via a two-stage chemical vapor deposition method. The maximum size of MoS2 crystals can be up to about 305 μm. The growth method can be used to grow other transition metal dichalcogenide crystals and lateral heterojunctions. The electron mobility of the MoS2 crystals can reach ≈30 cm2 V-1 s-1, which is comparable to those of exfoliated flakes.

Background: Pharmacological studies suggest that adenosine A3AR influences motility and colitis. Functional A3−/−AR knockout mice were used to prove whether A3AR activation is involved in modulating either motility or colitis. Methods: A3AR was probed by polymerase chain reaction (PCR) genotyping, Western blot, and immunochemistry. Motility was assessed in vivo by artificial bead-expulsion, stool-frequency, and FITC-dextran transit. Colitis was induced with dextran sodium sulfate (DSS) in A3−/−AR or wildtype (WT) age- and sex-matched controls. Progression of colitis was evaluated by histopathology, changes in myeloperoxidase (MPO), colon length, CD4+-cells, weight-loss, diarrhea, and the guaiac test. Results: Goat anti-hu-A3 antiserum identified a 66 kDa immunogenic band in colon. A3AR-immunoreactivity is expressed in SYN+-nerve varicosities, s-100+-glia, and crypt cells, but not 5-HT+ (EC), CD4+ (T), tryptase+ (MC), or muscle cells. A3AR immunoreactivity in myenteric ganglia of distal colon ≫ proximal colon by a ratio of 2:1. Intestinal transit and bead expulsion were accelerated in A3−/−AR mice compared to WT; stool retention was lower by 40%–60% and stool frequency by 67%. DSS downregulated A3AR in epithelia. DSS histopathology scores indicated less mucosal damage in A3−/−AR mice than WT. A3−/−AR phenotype protected against DSS-induced weight loss, neutrophil (MPO), or CD4+-T cell infiltration, colon shortening, change in splenic weight, diarrhea, or occult-fecal blood. Conclusions: Functional disruption of A3AR in A3−/−AR mice alters intestinal motility. We postulate that ongoing release of adenosine and activation of presynaptic-inhibitory A3AR can slow down transit and inhibit the defecation reflex. A3AR may be involved in gliotransmission. In separate studies, A3−/−AR protects against DSS colitis, consistent with a novel hypothesis that A3AR activation contributes to development of colitis. (Inflamm Bowel Dis 2010)

Introduction: A major theme in functional bowel disorders (FBD) such as irritable bowel syndrome (IBS) is that psychological/psychiatric problems have a pathogenic role, based both on the observation that patients with FBD are more anxious and depressed than healthy control, as well as research linking stress and depression to altered gastrointestinal sensory and motor function. However, recent experimental and epidemiological studies suggest that primary visceral disturbances can lead secondarily to persistent behavioral and emotional abnormalities. The aims of the present study were to test the hypothesis that mild chemical irritation of the colon of neonatal mice can produce changes in visceral hypersensitivity and psychological behaviors that persist into adulthood. Methods: Ten-day old C57BL/6 mouse pups received an intracolonic infusion of 20 μl of 0.5% acetic acid (IBS) or saline (control) to mimic a previously validated model of IBS in rats based on neonatal visceral irritation. Psychological behaviors and pain sensitivity of the colon were assessed when these mice were 8-14 weeks of age. Anxiety-like behaviors were tested using elevated plus maze and open field tests. Depression-like behavior was tested by the forced swim test. Colonic hypersensitivity to graded colorectal balloon distension (15, 30, 50 and 70mmHg) was determined by visceromotor responses (VMR) measured by electromyography of external oblique muscle. Resutls: Neonatal colorectal infusion of acetic acid but not saline significantly increased electromyographic activity in response to all of pressure colorectal distension in adults, suggesting the persistence of colonic hypersensitivity. In the elevated plus maze and open field tests, IBS mice showed a significant reduction in time spent in the open arms of elevated plus maze (control: 73.04±5.26s vs IBS: 53.54±6.53s, p