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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. [ABSTRACT FROM AUTHOR]

Optical interferometry is a promising alternative for acoustic detection as it records the changes of interference patterns. Apart from interferometric sensor heads, readout systems also play a crucial role in sensing performance. Here, inspired by the soliton molecule vibrations in ultrafast lasers, we introduce an efficient real-time spectral interferometry (RSI) approach to read out the Fabry–Pérot interferometer (FPI) for acoustic detection. Broadband pulses, emitted from an ultrafast fiber laser, are launched into the FPI sensor. Pseudo dual-pulse molecule is constructed by virtue of the equivalent two-beam interference of the FPI and modulated by the diaphragm transducer. The acoustic driven "molecular vibration" conforms to the sound applied on the metal diaphragm. Hence, the acoustic signals can be directly recorded by the successive dual-pulse spectral interferograms, imaged as a spectral encoded "soundtrack." We experimentally achieve the real-time characterization of both the audible and ultra sounds by retrieving the relative phase evolutions with a phase resolution of 37.6 mrad and preliminarily verifying the feasibility of the RSI in acoustic detection. This approach to wideband acoustic detection highlights an advanced application of ultrafast laser sources and paves an efficient way for interrogating the interferometric fiber sensors. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 λex = 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. [ABSTRACT FROM AUTHOR]

Most existing facility location models assume that the facility cost is either a fixed setup cost or made up of a fixed setup and a problem-specific concave or submodular cost term. This structural property plays a critical role in developing fast branch-and-price, Lagrangian relaxation, constant ratio approximation, and conic integer programming reformulation approaches for these NP-hard problems. Many practical considerations and complicating factors, however, can make the facility cost no longer concave or submodular. By removing this restrictive assumption, we study a new location model that considers general nonlinear costs to operate facilities in the facility location framework. The general model does not even admit any approximation algorithms unless P = NP because it takes the unsplittable hard-capacitated metric facility location problem as a special case. We first reformulate this general model as a set-partitioning model and then propose a branch-and-price approach. Although the corresponding pricing problem is NP-hard, we effectively analyze its structural properties and design an algorithm to solve it efficiently. The numerical results obtained from two implementation examples of the general model demonstrate the effectiveness of the solution approach, reveal the managerial implications, and validate the importance to study the general framework. [ABSTRACT FROM AUTHOR]

In this paper, a refractive index (RI) sensor is presented on the basis of the surface plasmon resonance (SPR) effect of double-ring hollow-core anti-resonant fiber (DR-HC-ARF), which has great sensitivity and wide detection range. In the design, the DR-HC-ARF consists of 12 silica tubes in two layers inside and outside, with the X-forward inner silica tube filled with gold wire. The simulation results indicated that the achievable maximum sensitivity, minimum resolution, and largest figure of merit of the DR-HC-ARF sensor filled with gold wire are −20600 nm/RIU, 4.85 × 10−6 RIU, and 615.79 RIU−1, respectively, when measuring using the confinement loss approach. The maximum sensitivity, minimum resolution, and largest birefringence of the DR-HC-ARF sensor filled with gold wire are −21200 nm/RIU, 4.71 × 10−6 RIU, and 2.38 × 10−4, respectively, for the birefringence analysis approach. The ultrahigh RI sensitivity of DR-HC-ARF sensor filled with gold wire paves a promising way on the applications in the field of biochemical detection. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Realization of a single white light emission (WLE) dyad is important for various applications, in particular, in display and light devices. In this work, we developed two BODIPY-based dyads BDP-B2 and BDP-B4 containing coumarin fluorophore connected to the 8-position of pyridinium with different aliphatic spacers. We found that BDP-B2 could show WLE in water/DMSO mixture solution. Detailed photophysical studies demonstrated that the coumarin emission, charge transfer (CT) and energy transfer (ET) are responsible for the WLE. • BDP-B2 could show white-light emission (WLE) in polar water/DMSO mixed solution. • Coumarin emission, charge transfer (CT) and energy transfer (ET) are responsible for the WLE from BDP-B2. • BDP-B2 would achieve color tunability in large area (blue-green-orange) of CIE diagram. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A novel donor-acceptor-donor (D-A-D') type of BODIPY derivative BDP-1 was synthesized and its fluorescence properties were investigated. By delicate tuning various parameters, e. g. solvent, concentration, excitation wavelength, aggregates of BDP-1 display single component white light emission (WLE), and the CIE coordinate values could be optimized to (0.33, 0.32). Detailed photophysical analysis by use of time-resolved spectroscopy and model compounds demonstrated that aggregation and further balance between energy transfer (ET) and intramolecular charge transfer (CT) from different groups in BDP-1 resulted in coordinated three primary color emissions which led to single component WLE. • A novel BODIPY derivative (BDP-1) was synthesized and its spectra properties were measured. • Single component WLE was realized through adjusting the concentration of BDP-1 and radiation wavelength. • The WLE was ascribed to the balanced mechanism of ET and CT states controlled by the aggregation of BDP-1. [ABSTRACT FROM AUTHOR]

• Ultrafast relaxation dynamics of six-thiophene film/crystal after excitation to lower and upper excited states was studied. • The first direct singlet fission in six-thiophene system with subsequent triplet-triplet annihilation in film was approved. • Enhanced lifetime of photocarriers (polarons) was obtained in 1 ms for crystal compared with 130–3700 ns for film. • Efficient polarons formation was approved (four times larger) upon excitation to upper excited singlet state (4.96 eV). The excited state dynamics of six-thiophene (6T) thin film and single crystal was studied by time-resolved fluorescence and femtosecond transient absorption techniques under different excitation conditions. The dominant process in 6T system is the generation of ion pairs, dissociated to polarons staying for up to 130−3700 ns in film and 1 ms in crystal. Singlet fission (SF) was directly observed from the upper vibrational levels of the first excited singlet state S 1 in 6T thin film/single crystal within 30 fs, which competes with intramolecular vibrational relaxation. Triplet state lifetime is dramatically shortened from 6T single crystal (1 ms) to thin film (4 ns) due to triplet-triplet annihilation, which is influenced by structural defects in amorphous regions of 6T film. Compared with 6T crystal, the partially ordered semicrystalline morphology of 6T film suggests the impact of well-structured crystallinity and molecular packing on the photocarriers transport dynamics and lifetime of triplet state. Moreover, excitation to upper excited singlet state (4.96 eV) leads to a higher yield of polarons (factor of 4), while SF in film/crystal is fully suppressed. Existence of long-lived photogenerated polarons may count π-conjugated oligomers as promising materials for developing organic-molecule-based optoelectroinc devices. [ABSTRACT FROM AUTHOR]

• 0D/2D heterostructures of oxygen deficient TiO 2 quantum dots confined in g-C 3 N 4 nanosheets (TiO 2- x /g-C 3 N 4) were prepared by in-situ pyrolysis. • Charge dynamics analysis indicate that interfacial charge transfer occurs from 2D-g-C 3 N 4 to 0D-TiO 2 in ultrafast time scale (<1 ps). The overall faster decay is assigned to shallow trapped charges in favor of electrons trapped by CO 2. • TiO 2- x /g-C 3 N 4 show high CO 2 adsorption ability enhanced visible light absorption, and efficient charge separation. • TiO 2- x /g-C 3 N 4 exhibit 5 times higher CO evolution than that of pristine g-C 3 N 4 under visible light irradiation. Two-dimensional graphitic carbon nitride (g-C 3 N 4) has been widely explored as a promising photocatalyst for solar CO 2 conversion. However, rapid charge recombination and low visible-light utilization are severely detrimental to photocatalytic CO 2 conversion. Zero-dimensional/two-dimensional (0D/2D) heterostructures are considered the promising materials with size tunability and enhanced charge separation efficiency for photocatalysis. Herein, a 0D/2D heterostructure of oxygen vacancy-rich TiO 2 quantum dots confined in g-C 3 N 4 nanosheets (TiO 2- x /g-C 3 N 4) was prepared by in-situ pyrolysis of NH 2 -MIL-125 (Ti) and melamine. Charge dynamics analysis by time-resolved photoluminescence (tr-PL) and femtosecond and nanosecond pump-probed transient absorption (TA) spectra revealed that charges transfer occured from 2D-g-C 3 N 4 to 0D-TiO 2 at an ultrafast subpicosecond time scale (<1 ps) through the intimate interface. The overall fast decay of the charge carriers was attributed to interfacial charge transfer, which was accompanied by recombination relaxation mediated by shallow trapped sites. Ultrafast interfacial charge transfer greatly promoted charge separation and electrons in shallow trapped sites were easily trapped by CO 2. In addition, combining with the synergetic advantage of strong visible light absorption, high CO 2 adsorption and large surface area, TiO 2- x /g-C 3 N 4 exhibited a superior CO evolution rate of 77.8 μmol g−1 h−1, roughly 5 times that of pristine g-C 3 N 4 (15.1 μmol g−1 h−1). This work provides in-depth insights into optimizing the heterojunction for robust solar CO 2 conversion. [ABSTRACT FROM AUTHOR]

Fundamental photocatalytic limitations of solar CO2 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‐C3Nx) located at both three‐coordinate N atoms and uncondensed terminal NHx species were prepared by one‐step tartaric acid‐assistant thermal polymerization of dicyandiamide. Transient absorption spectra revealed that the defects in g‐C3N4 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‐C3Nx 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‐C3Nx 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‐C3N4. This work presents the role of defects in modulating light absorption and charge separation, which opens an avenue to robust solar‐energy conversion performance. Between the sheets: Graphitic carbon nitride (g‐C3N4) nanosheets rich in nitrogen defects were obtained by one‐step tartaric acid‐assisted thermal polymerization of dicyandiamide. The defects in g‐C3N4 act as charge trapped states to prolong the lifetime of charge carriers, and the decreased interlayer distance caused by nitrogen vacancies favors of charge transport and mobility to the surface (see figure). Deficient g‐C3N4 exhibits the enhanced photocatalytic activity in CO2 reduction. [ABSTRACT FROM AUTHOR]

• Passively mode-locked fiber laser. • Time-stretch dispersion Fourier transform. • Internal dynamics and temporal distributions of tri-pulse structures. • Polarization and gain control. • Manipulation mechanism on internal dynamics. Self-assembly of ultrashort pulses highlights the complex patterns of dissipative solitons, termed soliton molecules in consideration of the particle-like behaviors. Multi-constituent temporal patterns release the degrees of freedom of versatile internal motions, emphasizing the molecular-analogous soliton dynamics and the advanced laser applications. Beyond previous studies, exploring the artificial manipulation of the intra-molecular dynamics would spread a new research horizon of ultrafast science. Here, we report the research on the manipulation mechanism on the internal dynamics under a tri-soliton model via the implementation of the polarization and gain control. Assisted with real-time spectral interferometry, both the binding separations and the relative phases are retrieved to unfold the intra-molecular dynamics of soliton triplets. Particularly, we present the switching among tri-soliton states identified by different binding separations and phase-evolving velocities, and further unveil the universal rules of the internal dynamics. All these findings provide an evident manifestation of the artificial manipulation on the temporal distributions and intra-molecular dynamics, as well as enable promising access to rapid multi-pulse reconfiguration applicable to fiber laser platforms. [ABSTRACT FROM AUTHOR]

A low-cost way of achieving a high sensitivity optical fiber strain sensor by introducing higher-order interference modes using a torsional multimode fiber (MMF) instead of normal MMF based on single-mode–multimode–single-mode (SMS) structure is proposed and the coupling mechanism of twist fiber is investigated theoretically. The sensor is fabricated by simple process of heating and twisting a small region of MMF. According to this method, the shift of multimode interference spectrum caused by an axial strain will be greatly magnified. Different strain sensitivities can be easily realized by controlling the torsional number of circles. The experimental results indicated a high strain sensitivity of 42.5 pm/ μ ε at most. [ABSTRACT FROM AUTHOR]

Histone deacetylase inhibitors (HDACi) have proven activity in hematologic malignancies, and their FDA approval in multiple myeloma (MM) and T-cell lymphoma highlights the need for further development of this drug class. We investigated AR-42, an oral pan-HDACi, in a first-in-man phase 1 dose escalation clinical trial. Overall, treatment was well tolerated, no DLTs were evident, and the MTD was defined as 40 mg dosed three times weekly for three weeks of a 28-day cycle. One patient each with MM and mantle cell lymphoma demonstrated disease control for 19 and 27 months (ongoing), respectively. Treatment was associated with reduction of serum CD44, a transmembrane glycoprotein associated with steroid and immunomodulatory drug resistance in MM. Our findings indicate that AR-42 is safe and that further investigation of AR-42 in combination regimens for the treatment of patients with lymphoma and MM is warranted. Trial registration:http://clinicaltrials.gov/ct2/show/NCT01129193 [ABSTRACT FROM PUBLISHER]

Abstract: Opa interacting protein 5 (OIP5), overexpressed in some types of human cancers, has been reported to be associated with the carcinogenesis of human cancer. However, the biological function and clinical significance of OIP5 in human Clear Cell Renal Cell Carcinoma (CCRCC) remains unknown. In the present study, we found the expression of OIP5 was markedly upregulated in surgical CCRCC specimens and CCRCC cell lines. Immunohistochemical analysis revealed that paraffin-embedded archival CCRCC specimens exhibited higher levels of OIP5 expression than normal renal tissues. Further statistical analysis suggested the upregulation of OIP5 was positively correlated with the Fuhrman grade (P =0.02), T classification (P =0.015), N classification (P =0.018) and clinical stage (P =0.035). Also, patients with high OIP5 expression dramatically exhibited shorter survival time (P =0.001). In addition, the OIP5 expression was an independent prognostic marker of overall survival of CCRCC patients in a multivariate analysis (P =0.008). Experimentally, we demonstrated that silencing OIP5 in CCRCC cell lines by specific siRNA clearly inhibited cell growth. In conclusion, our findings suggested that OIP5 could be a valuable marker of CCRCC progression and prognosis, and a promising therapeutic target for CCRCC. [Copyright &y& Elsevier]

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]