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Pre‐positioning emergency inventory in selected facilities is commonly adopted to prepare for potential disaster threat. In this study, we simultaneously optimize the decisions of facility location, emergency inventory pre‐positioning, and relief delivery operations within a single‐commodity disaster relief network. A min‐max robust model is proposed to capture the uncertainties in both the left‐ and right‐hand‐side parameters in the constraints. The former corresponds to the proportions of the pre‐positioned inventories usable after a disaster attack, while the latter represents the demands of the inventories and the road capacities in the disaster‐affected areas. We study how to solve the robust model efficiently and analyze a special case that minimizes the deprivation cost. The application of the model is illustrated by a case study of the 2010 earthquake attack at Yushu County in Qinghai Province of PR China. The advantage of the min‐max robust model is demonstrated through comparison with the deterministic model and the two‐stage stochastic model for the same problem. Experiment variants also show that the robust model outperforms the other two approaches for instances with significantly larger scales. [ABSTRACT FROM AUTHOR]

A phase interrogation method for a fiber-optic acoustic sensor based on a short-cavity extrinsic Fabry–Perot interferometer (EFPI) is proposed with two wavelengths. A multichannel tunable optical filter is employed, which selects out two monochromatic beams from the broadband interference spectrum of EFPI with fixed wavelength interval. The influence of the wavelength interval on the recovery of the phase signal has been theoretically and experimentally analyzed. To get the best sensitivity, the wavelength interval is fixed at one quarter of the period of sensor interference fringes. An optimized differential cross multiplication algorithm is utilized to demodulate the acoustic signal, which can eliminate the impact of optical power imbalance between the two light paths. This system may be a universal phase demodulation unit for short-cavity EFPI acoustic sensors. The EFPI acoustic sensing head is formed by an aluminum-attached polyethylene terephthalate membrane and a cleaved fiber tip. The sensor interrogated by the proposed demodulation system demonstrated large dynamic range in low-frequency domain under high sound pressure. A signal-to-noise ratio (SNR) of ∼53 dB is obtained at 80 Hz. These features make the sensor especially suitable for noise detection. [ABSTRACT FROM PUBLISHER]

Ultrafast fiber laser as a dissipative nonlinear system is capable of generating various dynamical soliton molecules, providing an abundant platform for investigating the transient soliton dynamics. Here, we report on the real-time internal motions of harmonically mode-locked soliton molecules (HMLSMs) in a passively mode-locked fiber laser with nonlinear polarization rotation (NPR). Assisted with time-stretch dispersive Fourier transform (DFT), various real-time scenarios towards multi-pulse states are revealed. Particularly, both the stationary and evolving HMLSMs are respectively observed, indicating that each soliton molecule in one roundtrip possesses identical intra-molecular motions. These vivid internal motions are mainly dominated by the underlying interactions and energy flow between the adjacent constituents. All these findings provide an intriguing perspective in dynamical intra-molecular evolution of ultrafast nonlinear phenomena and further enrich the research of fundamental science. • Various mode-locking states certify the harmonic mode-locking mechanisms. • Stationary and evolving soliton molecules reveal transient soliton dynamics. • Inherent similarity of harmonically mode-locked soliton molecules. [ABSTRACT FROM AUTHOR]

This paper proposes a novel microcone-curved resonant photoacoustic cell (MCR-PAC) for highly sensitive trace gas detection. The MCR-PAC features with microcone-curved resonant region and cylindrical buffer chamber, which dominates the photoacoustic signal amplification. By introducing the hyperbolic eccentricity as a new optimization dimension, the quality factor of the MCR-PAC is remarkably strengthened to enhance the acoustic pressure amplitude. At an eccentricity value of 5, the volume of the photoacoustic resonant cavity is approximately 0.23 cm 3 . Targeting trace acetylene, the system achieves a minimum detection limit of 1.41 ppb with an integration time of 290 s, corresponding normalized noise equivalent absorption coefficient is 1.88×10 -9 W·cm -1 ·Hz -1/2 . Compared to the traditional T-type PAC, the overall performance of MCR-PAC has been enhanced nearly fourfold. With its compact millimeter-scale dimensions and high sensitivity, the MCR-PAC demonstrates extensive potential for application in environmental monitoring and breath diagnostics., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier GmbH.)

To reduce noise in indoor visible light communication (IVLC), the Pearson correlation coefficient difference (PCCD), a denoising system combining iterative variational mode decomposition (IVMD) and multiple frequency shift keying modulation (MFSK), is proposed. Compared with VMD, the method can directly determine the optimal number of VMD modes and solve the issue of VMD penalty factor selection to some extent. The simulation results show that, when the input SNRs vary from -15 to -8 d B , the proposed method can improve the output SNRs of the 2FSK signal by an average of 15.5 dB and reduce the BER by 55.8%, improve the output SNR of the 4FSK signal by an average of 13 dB, and reduce the BER by 54.4%. The proposed method can also effectively suppress noise interference in real IVLC experiments at a distance of 1 m. In addition, the IVMD-MFSK denoising system can be applied to denoise all frequency-modulated signals with high applicability.

Photosensitizers have emerged as cytotoxic reactive oxygen species (ROS) activators in photodynamic therapy (PDT), which induced cell apoptosis. As the major contributors to ROS and oxidative stress, mitochondria play an important role in cell apoptosis. Although there are many reports about near-infrared 4,4-difluoro-4-bora-3a,4a-diaza- s -indacene (BODIPY) as photosensitizers (PSs) for PDT, this kind of PS has rarely been used for treating mitochondrial function and choroidal neovascularization application at the same time. Herein, a novel near-infrared PS (BDP2) characterized by good water solubility, long wavelength excitation, and high ROS quantum yield has been made. Under near-infrared light irradiation, BDP2 would generate ROS with high yield, induce a mitochondrial morphology change, and trigger cell apoptosis by changing the fusion protein level. Deep investigation revealed that BDP2 can cause oxidative stress, break the balance between fusion and fission of mitochondrial dynamics protein through decreasing fusion protein MFN2 and OPA1 expression, and finally cause cell apoptosis. Due to these characteristics, the BDP2 PS was used to treat choroidal neovascularization in animal models and can inhibit neovascularization.

Background: The composition of kidney stones is related to the hardness of the stones. Knowing the composition of the stones before surgery can help plan the laser power and operation time of percutaneous nephroscopic surgery. Moreover, patients can be treated with medications if the kidney stone is compounded by uric acid before treatment, which can relieve the patients of the pain of surgery. However, although the literature generally reports the kidney stone composition analysis method base on dual-energy CT images, the accuracy of these methods is not enough; they need manual delineation of the kidney stone location, and these methods cannot analyze mixed composition kidney stones., Objective: This study aimed to overcome the problem related to identifying kidney stone composition; we need an accurate method to analyze the composition of kidney stones., Methods: In this paper, we proposed the automatic kidney stone composition analysis algorithm based on a dual-energy CT image. The algorithm first segmented the kidney stone mask by deep learning model, then analyzed the composition of each stone by machine learning model., Results: The experimental results indicate that the proposed algorithm can segment kidney stones accurately (AUC=0.96) and predict kidney stone composition accurately (mean Acc=0.86, mean Se=0.75, mean Sp=0.9, mean F1=0.75, mean AUC=0.83, MR (Exact match ratio)=0.6)., Conclusion: The proposed method can predict the composition and location of kidney stones, which can guide its treatment. Experimental results show that the weighting strategy can improve kidney stone segmentation performance. In addition, the multi-label classification model can predict kidney stone composition precisely, including the mixed composition kidney stones., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

We propose, what we believe to be, a novel method for high temperature sensing calibration based on the mechanism of alterable interferential fineness in Bragg hollow core fiber (BHCF). To verify the proof-of-concept, the fabricated sensing structure is sandwiched by two sections with different length of BHCF. Two interferential fineness fringes dominate the transmission spectrum, where the high-fineness fringes formed by anti-resonant reflecting optical waveguide (ARROW) plays the role for high temperature measurement. Meanwhile, the low-fineness fringes induced by short Fabry-Perot (F-P) cavity are exploited as temperature calibration. The experimental results show that the ARROW mechanism-based temperature sensitivity can reach 26.03 pm/°C, and the intrinsic temperature sensitivity of BHCF is 1.02 pm/°C. Here, the relatively lower magnitude of the temperature sensitivity is considered as the standard value since it merely relies on the material properties of silicon. Additionally, a large dynamic temperature range from 100 °C to 800 °C presents linear response of the proposed sensing structure, which may shine the light on the sensing applications in the harsh environment.

To compare the safety and efficacy of en bloc resection of non-muscle-invasive bladder cancer (NMIBC) using a 1470-/980-nm dual-wavelength laser (DwLRBT) compared to the gold standard, transurethral resection (TURBT). The study group included 251 patients with a confirmed diagnosis of NMIBC, 97 in the DwLRBT group and 154 in the TURBT group. Clinical characteristics, complications, and recurrence-free survival were compared between the two groups. There were no differences between the two groups with regard to age, sex, mean tumor size, mean tumor number, tumor location, risk, fever, and reoperation. Compared to TURBT, DwLRBT was associated with a shorter hospitalization time (mean±standard deviation: 5.81±1.48 days vs. 4.96±1.32, respectively, p=0.001), shorter catheterization time (4.98±1.47 vs. 4.20±1.48 days, respectively; p=0.035), and smaller volume of intraoperative bleeding (8.43±6.21 ml vs. 6.15±5.08, respectively; p=0.003). Recurrence-free survival (RFS) was better for DwLRBT than TURBT in the overall cohort (hazard ratio [HR], 0.4323; 95% confidence interval [CI], 0.2852-0.6554; p=0.0004) and for the following subgroups and tumor types: intermediate-risk (HR, 0.2654; 95%CI, 0.1020-0.6904; p=0.0245) and high-risk (HR, 0.4461; 95% CI, 0.2778-0.7162; p=0.0027) groups; and for pedunculate bladder tumors (HR, 0.4158; 95%CI, 0.2401-0.7202; p=0.0063), single bladder tumors (HR, 0.4136; 95%CI, 0.2376-0.7293; p=0.0072), and multiple bladder tumors (HR, 0.2727; 95%CI, 0.1408-0.5282; p=0.0014). DwLRBT is associated with better operative and postoperative outcomes, including, importantly, a longer RFS, compared to TURBT., (© 2023. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

We investigate dynamic signatures of the singlet fission (SF) process triggered by the excitation of a molecular system to an upper singlet state S N ( N > 1) and develop a computational methodology for the simulation of nonlinear spectroscopic signals revealing the S N → TT 1 SF in real time. We demonstrate that SF can proceed directly from the upper state S N , bypassing the lowest excited state, S 1 . We determine the main S N → TT 1 reaction pathways and show by computer simulation and spectroscopic measurements that the S N -initiated SF can be faster and more efficient than the traditionally studied S 1 → TT 1 SF. We claim that the S N → TT 1 SF offers novel promising opportunities for engineering SF systems and enhancing SF yields.

Ultrahigh-order optical orbital angular momentum (OAM) states of the identification over ±270 orders are implemented by annular phase grating (APG) and Gaussian beams with different wavelengths. Particularly, the far-field diffraction intensity patterns feature the spiral stripes instead of Hermitian-Gaussian (HG)-like fringes. It's worth noting that the spiral stripes present uniform distribution, thus the order of OAM states can be intuitively acquired. More specifically, the OAM states can be confirmed from the total amount and rotating direction of the spiral stripes. Compared with traditional methods, the propose scheme contributes to the perfect-distributed and sharper spiral stripes. Moreover, it also makes an easier observation of the patterns in the CCD camera with limited imaging targets. In our experimental setup, the optical filter is removed and the APG parameters are not strictly required. Therefore, the propose optical transmission system is equipped with the advantages of efficiency, robustness and low cost, which paves a promising way for the communication capacity enhancement.

The ultrafast dynamics of triplet excitons and polarons in hexaphenyl film was investigated by time-resolved fluorescence and femtosecond transient absorption techniques under various excitation photon energies. Two distinct pathways of triplet formation were clearly observed. Long-lived triplet states are populated within 4.5 ps via singlet fission-intersystem crossing, while the short-lived triplet states (1.5 ns) are generated via singlet fission from vibrational electronic states. In the meantime, polarons were formed from hot excitons on a timescale of <30 fs and recombined in ultrafast lifetime (0.37 ps). In addition, the characterization of hexaphenyl film suggests the morphologies of crystal and aggregate to wide applications in organic electronic devices. The present study provides a universally applicable film fabrication in hexaphenyl system towards future singlet fission-based solar cells.

Attaching stable radicals to organic chromophores is an effective method to enhance the intersystem crossing (ISC) of the chromophores. Herein we prepared perylene-oxoverdazyl dyads either by directly connecting the two units or using an intervening phenyl spacer. We investigated the effect of the radical on the photophysical properties of perylene and observed strong fluorescence quenching due to radical enhanced ISC (REISC). Compared with a previously reported perylene-fused nitroxide radical compound (triplet lifetime, τ T =0.1 μs), these new adducts show a longer-lived triplet excited state (τ T =9.5 μs). Based on the singlet oxygen quantum yield (Φ Δ =7 %) and study of the triplet state, we propose that the radical enhanced internal conversion also plays a role in the relaxation of the excited state. Femtosecond fluorescence up-conversion indicates a fast decay of the excited state (<1.0 ps), suggesting a strong spin-spin exchange interaction between the two units. Femtosecond transient absorption (fs-TA) spectra confirmed direct triplet state population (within 0.5 ps). Interestingly, by fs-TA spectra, we observed the interconversion of the two states (D 1 ↔Q 1 ) at ∼80 ps time scale. Time-resolved electron paramagnetic resonance (TREPR) spectral study confirmed the formation of the quartet sate. We observed triplet and quartet states simultaneously with weights of 0.7 and 0.3, respectively. This is attributed to two different conformations of the molecule at excited state. DFT computations showed that the interaction between the radical and the chromophore is ferromagnetic (J>0, 0.05∼0.10 eV)., (© 2022 Wiley-VCH GmbH.)

Plasmonic nanostructures have tremendous potential to be applied in photocatalytic CO 2 reduction, since their localized surface plasmon resonance can collect low-energy-photons to derive energetic "hot electrons" for reducing the CO 2 activation-barrier. However, the hot electron-driven CO 2 reduction is usually limited by poor efficiency and low selectivity for producing kinetically unfavorable hydrocarbons. Here, a new idea of plasmonic active "hot spot"-confined photocatalysis is proposed to overcome this drawback. W 18 O 49 nanowires on the outer surface of Au nanoparticles-embedded TiO 2 electrospun nanofibers are assembled to obtain lots of Au/TiO 2 /W 18 O 49 sandwich-like substructures in the formed plasmonic heterostructure. The short distance (< 10 nm) between Au and adjacent W 18 O 49 can induce an intense plasmon-coupling to form the active "hot spots" in the substructures. These active "hot spots" are capable of not only gathering the incident light to enhance "hot electrons" generation and migration, but also capturing protons and CO through the dual-hetero-active-sites (Au-O-Ti and W-O-Ti) at the Au/TiO 2 /W 18 O 49 interface, as evidenced by systematic experiments and simulation analyses. Thus, during photocatalytic CO 2 reduction at 43± 2 °C, these active "hot spots" enriched in the well-designed Au/TiO 2 /W 18 O 49 plasmonic heterostructure can synergistically confine the hot-electron, proton, and CO intermediates for resulting in the CH 4 and CO production-rates at ≈35.55 and ≈2.57 µmol g -1 h -1 , respectively, and the CH 4 -product selectivity at ≈93.3%., (© 2022 Wiley-VCH GmbH.)

Background: The role of HERV-H LTR-associating 2 (HHLA2) in cancer remains still unclear. This study analyzed the correlation between the prognosis and immune infiltrate function of HHLA2 in pan-cancers., Methods: HHLA2 expression in pan-cancers was analyzed using the databases of TCGA, GTEx, TIMER, GEPIA, UALCAN, and GSEA databases. Multiple bioinformatic methods were used to investigate the correlation of HHLA2 expression with survival, pathological stage, tumor mutation burden (TMB), microsatellite instability (MSI), tumor microenvironment (TME), immune cell infiltration, and immune checkpoint gene (ICG), and gene functional enrichment was performed by Gene Set Enrichment Analysis (GSEA) and Gene Set Variation Analysis (GSVA)., Results: HHLA2 was aberrantly expressed and was strongly correlated with positive or negative prognosis in multiple human cancers, which revealed that HHLA2 might play a vital role during cancer formation and development. Kaplan-Meier (KM) curves across cancers revealed that HHLA2 expression was correlated with overall survival (OS) in eight cancers, disease-specific survival (DSS) in seven cancers, disease-free interval (DFI) in four cancers, and progression-free interval (PFI) in nine cancers. Furthermore, HHLA2 expression was positively correlated with TMB in 6 cancer types and negatively associated with TMB in 7 cancer types, respectively. The former included ESCA, HNSC, KIRP, PAAD, PRAD, and PCPG; the latter contained COAD, LGG, LUAD, LUSC, THYM, THCA, and UCEC. Additionally, we found HHLA2 expression was negatively related to MSI in ACC, COAD, PAAD, and UCEC. More importantly, HHLA2 expression was remarkably correlated with the degree of tumor-infiltrating immune in many cancers, including B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells and strongly associated with immune checkpoint genes in 13 tumor types. Furthermore, KEGG pathway analyses indicated that HHLA2 could potentially impact cancer etiology or pathogenesis by functioning in amino sugar and nucleotide sugar metabolism, cytosolic DNA sensing pathway, and peroxisome pathways. Meanwhile, GSVA analysis results all indicate that HHLA2 was correlated with TSC/mTOR, RTK, RAS/MAPK, PI3K/AKT, EMT, DNA Damage Response, Cell Cycle, and Apoptosis pathways in various cancers., Conclusion: HHLA2 can function as a prognostic biomarker and correlate with tumor immunity in human pan-cancer due to its important role in tumorigenesis and immune infiltration, which provides new insight into developing new targeted treatments in cancers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be constructed as a potential., (Copyright © 2022 Zeng Yang et al.)

Background and Aims: With the increasing coexistence of cardiovascular disease and cancer in contemporary clinical practice, studies on the outcomes in acute myocardial infarction (AMI) patients with cancer has not been systematically investigated. This study sought to investigated the effect of coexisting cancer on the treatment and clinical outcomes among AMI patients., Methods: We retrospectively integrated and analyzed cardiovascular data of 6,607 AMI patients between June 2016 and December 2019. Patients with cancer were compared with pair-matched cancer-naive patients. Cox proportional hazards models were constructed to compare the differences in outcomes., Results: Of 6,607 patients, 2.3% ( n = 150) had been diagnosed with cancer. Patients with cancer were older (70.3 ± 10.0 vs. 63.9 ± 11.5 years, P < 0.001) and had a higher burden of comorbidities. Moreover, patients with cancer tended to receive clopidogrel (52.0 vs. 40.0%, P = 0.004) rather than ticagrelor (45.6 vs. 58.2%, P = 0.003) than those without cancer. After pairwise matching, patients with cancer were less likely to undergo in-hospital percutaneous coronary intervention (61.3 vs. 70.0%, P = 0.055). And after 3-year follow-up, the cumulative incidence of cardiovascular death (14.0 vs. 8.3%; adjusted HR, 1.93; 95% CI, 1.11-3.39; P = 0.021) among patients with cancer was significantly higher than that among the matched controls, a similar pattern was observed for the composite outcome of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke (16.0 vs. 10.3%; adjusted HR, 1.98; 95% CI, 1.21-3.26; P = 0.007). Moreover, patients with a historical cancer diagnosis within 5 years had a higher risk of cardiovascular ischemic events., Conclusions: AMI patients with a concomitant diagnosis of cancer tended to be treated with conservative therapies and were at substantially higher risk for adverse cardiovascular outcomes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Peng, Wang, Cao, Zheng, Tian, Yu, Ni, Wang, Qin, Zhao, Tian and Yu.)

The most common type of kidney tumor, clear-cell renal cell carcinoma (ccRCC) with relatively insidious development and easily metastatic characteristics is generally insensitive to cytotoxic chemotherapy. The abundant polyunsaturated fatty acids (PUFAs) content in advanced ccRCC allows it to be intrinsically vulnerable to ferroptosis-based therapeutic strategies. Nevertheless, the strategy to cause the "iron overload" by administration with iron-based nanomaterials has limited therapeutic efficacy. And the classic ferroptosis agonist (RSL3) with low specificity for tumors, short half-life in the blood, poor water solubility and deficient accumulation at the tumor site prevents its reliable application in vivo . In this study, iron-based metal-organic framework nanoparticles (MIL-101(Fe) NPs) delivered RSL3 to ccRCC tumors, and then released the iron ions and RSL3 accompanied by the degradation of MIL-101(Fe) NPs in the acidic tumor microenvironment. The MIL-101(Fe)@RSL3 as a pH-responsive nanodrug causes cellular iron overload and promotes the hydroxyl radical ( • OH) generation by Fenton reaction to attack PUFAs, leading to the aberrant accumulation of lipid peroxides (L-OOH). Additionally, RSL3 directly inhibits glutathione peroxidase 4 (GPX4) to detoxify L-OOH, and ferrous ions further catalyze the irreversible conversion of highly reactive lipid alkoxyl radicals (L-O • ) from L-OOH to triggering waterfall-like cascade ferroptosis. In contrast to the limited antitumor efficiency of free RSL3, MIL-101(Fe)@RSL3 with high encapsulation efficiency (88.7%) shows a significant ccRCC-specific antitumor effect and negligible side effects. Taken together, MIL-101(Fe)@RSL3 could aggravate ferroptosis and be expected to be a promising nanodrug for ccRCC systemic therapy due to the targeted delivery and responsive release of RSL3 and iron ions.

Two-dimensional transition metal dichalcogenides have attracted a great deal of attention in the past few decades owing to their attractive optoelectronic properties. However, their widespread utility in photonic devices and components is still limited owing to their weak photoluminescence. While various treating methods are in place to improve the photoluminescence yield, the impact of these treatments on the excited state (especially exciton) dynamics in these two-dimensional materials remains ill defined. In this work, exciton dynamics in pristine and oleic acid-treated monolayer WS 2 were comprehensively studied through various ultrafast experimental techniques. We demonstrate that oleic acid effectively passivates the defect states in as-fabricated WS 2 , resulting in trap-free exciton dynamics and exciton annihilation rate reduction, which leads to stronger steady-state photoluminescence and longer photoluminescence lifetime. These results provide valuable information on the intrinsic exciton dynamics in monolayer WS 2 , which could also be applicable in other two-dimensional transition metal dichalcogenides and help improve optoelectronic device performance.

Multimodality imaging can reveal complementary anatomic and functional information as they exploit different contrast mechanisms, which has broad clinical applications and promises to improve the accuracy of tumor diagnosis. Accordingly, to attain the particular goal, it is critical to exploit multimodal contrast agents. In the present work, we develop novel cobalt core/carbon shell-based nanoparticles (Cobalt at carbon NPs) with both magnetization and light absorption properties for dual-modality magnetic resonance imaging (MRI) and photoacoustic imaging (PAI). The nanoparticle consists of ferromagnetic cobalt particles coated with carbon for biocompatibility and optical absorption. In addition, the prepared Cobalt at carbon NPs are characterized by transmission electron microscope (TEM), visible-near-infrared spectra, Raman spectrum, and X-ray powder diffraction for structural analysis. Experiments verify that Cobalt at carbon NPs have been successfully constructed and the designed Cobalt at carbon NPs can be detected by both MRI and PAI in vitro and in vivo . Importantly, intravenous injection of Cobalt at carbon NPs into glioblastoma-bearing mice led to accumulation and retention of Cobalt at carbon NPs in the tumors. Using such a multifunctional probe, MRI can screen rapidly to identify potential lesion locations, whereas PAI can provide high-resolution morphological structure and quantitative information of the tumor. The Cobalt at carbon NPs are likely to become a promising candidate for dual-modality MRI/PAI of the tumor., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Li, Ye, Zhang, Ni, Wen and Qin.)

A long 0.9 ps lifetime of the upper excited singlet state in perylene is resolved by femtosecond pump-probe measurements under ultraviolet (4.96 eV) excitation and further validated by theoretical simulations of transient absorption kinetics. This finding prompts exploration and development of novel perylene-based materials for upper excited state photochemistry applications.

With the aim of constructing efficient photoelectric organic materials, a pyrido[3,2- g ]quinoline derivative named LA17b has been synthesized, and its photodynamic relaxation processes in solvents and films were studied by time-resolved fluorescence and femtosecond transient absorption techniques. The steady-state fluorescence spectra show pronounced red-shift with the increase of the solvent polarity as well as in binary solvent hexane/ethanol by increasing ethanol concentration. However, the strong red-shift does not lead to quenching of the fluorescence. This is explained in terms of a twisted intramolecular charge transfer (TICT) state. The TICT state of LA17b in ethanol is highly emissive with a long fluorescence lifetime: 1.1 ns. TICT state was shown to play an important role in enhancement of intersystem crossing rate. TD-DFT calculations confirm the pathways of relaxation of locally excited state via TICT and triplet states. In films, the photodynamic properties are similar to that of LA17b in hexane and the TICT state vanishes due to the rigid environment. The obtained optical properties of this molecule suggest that it can be a promising candidate for various optoelectronic applications.

New Delhi metallo-β-lactamases (NDMs), including at least 28 variants, are a rapidly emerging family of β-lactamases worldwide, with a variety of infections caused by NDM-positive strains usually associated with very poor prognosis and high mortality. NDMs are the most prevalent carbapenemases in Escherichia coli ( E. coli ) worldwide, especially in China. The vast majority of bla NDM cases occur on plasmids, which play a vital role in the dissemination of bla NDM . To systematically explore the relationships between plasmids and bla NDM genes in E. coli and obtain an overall picture of the conjugative and mobilizable bla NDM -positive plasmids, we analyzed the variants of bla NDM , replicon types, phylogenetic patterns, conjugative transfer modules, host STs, and geographical distributions of 114 bla NDM -positive plasmids, which were selected from 3786 plasmids from 1346 complete whole genomes of E. coli from the GenBank database. We also established links among the characteristics of bla NDM -positive plasmids in E. coli . Eight variants of bla NDM were found among the 114 bla NDM -positive plasmids, with bla NDM - 5 (74 bla NDM - 5 genes in 73 plasmids), and bla NDM - 1 (31 bla NDM - 1 genes in 28 plasmids) being the most dominant. The variant bla NDM - 5 was mainly carried by the IncX3 plasmids and IncF plasmids in E. coli , the former were mainly geographically distributed in East Asia (especially in China) and the United States, and the latter were widely distributed worldwide. IncC plasmids were observed to be the predominant carriers of bla NDM - 1 genes in E. coli , which were mainly geographically distributed in the United States and China. Other bla NDM - 1 -carrying plasmids also included IncM2, IncN2, and IncHI1. Moreover, the overall picture of the conjugative and mobilizable bla NDM -positive plasmids in E. coli was described in our study. Our findings enhance our understanding of the genetic diversity and characteristics of bla NDM -positive plasmids in in E. coli ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhang, Guo, Li, Li, Yang, Ni, Zhan, Lu, Zhang, Li and Zhou.)

Singlet exciton fission (SF) is a spin-allowed process whereby two triplet excitons are created from one singlet exciton. This phenomenon can offset UV photon energy losses and enhance the overall efficiency in photovoltaic devices. For this purpose, it requires photostable commercially available SF materials. Excited state dynamics in pure perylene film, ease of commercial production, is studied by time-resolved fluorescence and femtosecond transient absorption techniques under different photoexcitation energies. In film, polycrystalline regions contain perylene in H-type aggregate form. SF takes place from higher excited states of these aggregates in ultrafast time scale < 30 fs, reaching a triplet formation quantum yield of 108%. Moreover, at λ ex  = 450 nm singlet fission was detected as a result of two-quantum absorption. Other competing relaxation channels are excimer (1 ps) and dimer radical cation formation (< 30 fs). Excimer radiatively relaxes within 19 ns and radical cation recombines in 3.2 ns. Besides, exciton self-trapping by crystal lattice distortions occurs within hundreds of picosecond. Our results highlight potential of simple-fabricated perylene films with similar properties as high-cost single crystal in SF based photovoltaic applications.

Fundamental photocatalytic limitations of solar CO 2 reduction remain due to low efficiency, serious charge recombination, and short lifetime of catalysts. Herein, two-dimensional graphitic carbon nitride nanosheets with nitrogen vacancies (g-C 3 N x ) located at both three-coordinate N atoms and uncondensed terminal NH x species were prepared by one-step tartaric acid-assistant thermal polymerization of dicyandiamide. Transient absorption spectra revealed that the defects in g-C 3 N 4 act as trapped states of charges to result in prolonged lifetimes of photoexcited charge carriers. Time-resolved photoluminescence spectroscopy revealed that the faster decay of charges is due to the decreased interlayer stacking distance in g-C 3 N x in favor of hopping transition and mobility of charge carriers to the surface of the material. Owing to the synergic virtues of strong visible-light absorption, large surface area, and efficient charge separation, the g-C 3 N x nanosheets with negligible loss after 15 h of photocatalysis exhibited a CO evolution rate of 56.9 μmol g -1  h -1 under visible-light irradiation, which is roughly eight times higher than that of pristine g-C 3 N 4 . This work presents the role of defects in modulating light absorption and charge separation, which opens an avenue to robust solar-energy conversion performance., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The black TiO 2 nanoparticles are synthesized via a facile calcination method combined with an in-situ controllable solid-state reaction approach. The results indicate that the photocatalyst with a narrow band gap of ~2.32 eV extends the photoresponse to visible light and near infrared region. And thus more reactive oxygen species can be obtained to induce the cell-killing under 808 nm light triggering. The as-obtained black TiO 2 nanoparticles exhibiting low toxicity, good biocompatibility and high anticancer effect in vitro, is demonstrated as efficient photosensitizers for phototherapy to kill the bladder cancer cells. These findings suggest that the facile synthetic black TiO 2 nanomaterials will have broad application in biomedicine., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Purpose: Based on the promising activity and tolerability of flavopiridol administered with a pharmacokinetically-derived dosing schedule in chronic lymphocytic leukemia (CLL), we conducted a phase I study using this schedule in patients with advanced solid tumors., Experimental Design: Flavopiridol was given IV as a 30-min loading dose followed by a 4-hr infusion weekly for 4 weeks repeated every 6 weeks. Dose-escalation was in cohorts of three patients using the standard 3+3 phase I study design. Blood samples were obtained for pharmacokinetic and pharmacodynamic studies., Results: Thirty-four eligible patients with advanced solid tumors received a total of 208 doses (median 7, range 1-24). Total doses ranged from 40 to 105 mg/m(2). The primary dose limiting toxicity was cytokine release syndrome (CKRS). No antitumor responses were observed. The mean peak plasma concentration across all doses was 1.65 ± 0.86 μM. Area under the concentration-versus-time curve ([Formula: see text]) ranged from 4.31 to 32.2 μM[Symbol: see text]hr with an overall mean of 13.6 ± 7.0 μM[Symbol: see text]hr. Plasma flavopiridol concentrations and AUC increased proportionally with dose. There was no correlation between cytokine levels and clinical outcomes., Conclusions: The maximum-tolerated dose of flavopiridol is 20 mg/m(2) bolus followed by 20 mg/m(2) infusion over 4 h given weekly for 4 weeks on a 6-week cycle in patients with advanced solid tumors. Flavopiridol PK was notably different, and there was a higher frequency of CKRS, despite prophylactic steroids, seen in this patient group compared to previous studies with CLL using a similar dosing schedule.

Background: A pharmacokinetically derived schedule of flavopiridol administered as a 30 min intravenous bolus followed by 4-hour continuous intravenous infusion (IVB/CIVI) is active in fludarabine-refractory chronic lymphocytic leukemia, but no studies examining the feasibility and maximum tolerated dose of this schedule have been reported in acute leukemia., Design and Methods: We conducted a phase I dose escalation trial of single-agent flavopiridol in adults with relapsed/refractory acute leukemias, utilizing a modification of the intravenous bolus/continuous intravenous infusion approach, intensifying treatment for administration on days 1, 2, and 3 of 21-day cycles., Results: Twenty-four adults with relapsed/refractory acute myeloid leukemia (n=19) or acute lymphoblastic leukemia (n=5) were enrolled. The median age was 62 years (range, 23-78). The maximum tolerated dose of flavopiridol was 40 mg/m(2) intravenous bolus plus 60 mg/m(2) continuous intravenous infusion (40/60). The dose limiting toxicity was secretory diarrhea. Life-threatening hyperacute tumor lysis syndrome requiring hemodialysis on day 1 was observed in one patient. Pharmacokinetics were dose-dependent with increased clearance observed at the two highest dose levels. Diarrhea occurrence and severity significantly correlated with flavopiridol concentrations at the end of the 4-hour infusion, volume of distribution, and elimination half-life. Modest anti-leukemic activity was observed, with most patients experiencing dramatic but transient reduction/clearance of circulating blasts lasting for 10-14 days. One refractory acute myeloid leukemia patient had short-lived complete remission with incomplete count recovery., Conclusions: Flavopiridol as a single agent given by intravenous bolus/continuous intravenous infusion causes marked, immediate cytoreduction in relapsed/refractory acute leukemias, but objective clinical responses were uncommon. With this schedule, the dose is limited by secretory diarrhea.

Mutation of the p53 tumor suppressor is associated with disease progression, therapeutic resistance, and poor prognosis in patients with lymphoid malignancies and can occur in approximately 50% of Burkitt lymphomas. Thus, new therapies are needed to specifically target p53-deficient lymphomas with increased efficacy. In the current study, the specific impact of inhibition of the small GTPase Rac1 on p53-deficient B- and T-lymphoma cells was investigated. p53 deficiency resulted in increased Rac1 activity in both B-cell and T-cell lines, and its suppression was able to abrogate p53 deficiency-mediated lymphoma cell proliferation. Further, Rac targeting resulted in increased apoptosis via a p53-independent mechanism. By probing multiple signaling axes and performing rescue studies, we show that the antiproliferative effect of Rac1 targeting in lymphoma cells may involve the PAK and Akt signaling pathway, but not the mitogen-activated protein (MAP) kinase pathway. The effects of inhibition of Rac1 were extended in vivo where Rac1 targeting was able to specifically impair p53-deficient lymphoma cell growth in mouse xenografts and postpone lymphomagenesis onset in murine transplantation models. Because the Rac1 signaling axis is a critical determinant of apoptosis and tumorigenesis, it may represent an important basis for therapy in the treatment of p53-deficient lymphomas.