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Phycocyanin 620 (PC620) is the outermost light-harvesting complex in phycobilisome of cyanobacteria, engaged in light collection and energy transfer to the core antenna, allophycocyanin. Recently, long-lived exciton-vibrational coherences have been observed in allophycocyanin, accounting for the coherent energy transfer [Zhu et al., Nat. Commun. 15, 3171 (2024)]. PC620 has a nearly identical spatial location of three α84-β84 phycocyanobilin pigment pairs to those in allophycocyanin, inferring an existence of possible coherent energy transfer pathways. However, whether PC620 undergoes coherent or incoherent energy transfer remains debated. Furthermore, accurate determination of energy transfer rates in PC620 is still necessary owing to the spectral overlap and broadening in conventional time-resolved spectroscopic measurements. In this work, the energy transfer process within PC620 was directly resolved by polarization-controlled two dimensional electronic spectroscopy (2DES) and global analysis. The results show that the energy transfer from α84 to the adjacent β84 has a lifetime constant of 400 fs, from β155 to β84 of 6-8 ps, and from β155 to α84 of 66 ps, fully conforming to the Förster resonance energy transfer mechanism. The circular dichroism spectrum also reveals that the α84-β84 pigment pair does not form excitonic dimer, and the observed oscillatory signals are confirmed to be vibrational coherence, excluding the exciton-vibrational coupling. Nodal line slope analysis of 2DES further reveals that all the vibrational modes participate in the energy dissipation of the excited states. Our results consolidate that the ultrafast energy transfer process in PC620 is incoherent, where the twisted conformation of α84 is suggested as the main cause for preventing the formation of α84-β84 excitonic dimer in contrast to allophycocyanin., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Understanding the dynamics of excited-state vibrational energy relaxation in photosynthetic pigments is crucial for elucidating the mechanisms underlying energy transfer processes in light-harvesting complexes. Utilizing advanced femtosecond broadband transient fluorescence (TF) spectroscopy, we explored the excited-state vibrational dynamics of Chlorophyll-a (Chl-a) both in solution and within the light-harvesting complex II (LHCII). We discovered a vibrational cooling (VC) process occurring over ∼6 ps in Chl-a in ethanol solution following Soret band excitation, marked by a notable ultrafast TF blueshift and spectral narrowing. This VC process, crucial for regulating the vibronic lifetimes, was further elucidated through the direct observation of the population dynamics of higher vibrational states within the Qy electronic state. Notably, Chl-a within LHCII demonstrated significantly faster VC dynamics, unfolding within a few hundred femtoseconds and aligning with the ultrafast energy transfer processes observed within the complex. Our findings shed light on the complex interaction between electronic and vibrational states in photosynthetic pigments, underscoring the pivotal role of vibrational dynamics in enabling efficient energy transfer within light-harvesting complexes., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Obesity has long been thought to be a main cause of hyperlipidemia. As a systemic disease, the impact of obesity on organs, tissues and cells is almost entirely negative. However, the relationship between obesity and bone loss is highly controversial. On the one hand, obesity has long been thought to have a positive effect on bone due to increased mechanical loading on the skeleton, conducive to increasing bone mass to accommodate the extra weight. On the other hand, obesity-related metabolic oxidative modification of low-density lipoprotein (LDL) in vivo causes a gradual increase of oxidized LDL (ox-LDL) in the bone marrow microenvironment. We have reported that low-density lipoprotein receptor-related protein 6 (LRP6) acts as a receptor of ox-LDL and mediates the bone marrow stromal cells (BMSCs) uptake of ox-LDL. We detected elevated serum ox-LDL in obese mice. We found that ox-LDL uptake by LRP6 led to an increase of intracellular reactive oxygen species (ROS) in BMSCs, and N-acetyl-L-cysteine (NAC) alleviated the cellular senescence and impairment of osteogenesis induced by ox-LDL. Moreover, LRP6 is a co-receptor of Wnt signaling. We found that LRP6 preferentially binds to ox-LDL rather than dickkopf-related protein 1 (DKK1), both inhibiting Wnt signaling and promoting BMSCs senescence. Mesoderm development LRP chaperone (MESD) overexpression inhibits ox-LDL binding to LRP6, attenuating oxidative stress and BMSCs senescence, eventually rescuing bone phenotype., Competing Interests: Declaration of competing interest 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 © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Polylactic acid (PLA) has attracted increasing interest as a sustainable plastic because it can be degraded into CO 2 and H 2 O in nature. However, this process is sluggish, and even worse, it is a CO 2 -emitting and carbon resource waste process. Therefore, it is highly urgent to develop a novel strategy for recycling post-consumer PLA to achieve a circular plastic economy. Herein, we report a one-pot photoreforming route for the efficient and selective amination of PLA waste into value-added alanine using CoP/CdS catalysts under mild conditions. Results show the alanine production rate can reach up to 2.4 mmol g cat -1 h -1 , with a high selectivity (>75 %) and excellent stability. Time-resolved transient absorption spectra (TAS) reveal that CoP can rapidly extract photogenerated electrons from CdS to accelerate proton reduction, favoring hole-dominated PLA oxidation to coproduce alanine. This study offers an appealing way for upcycling PLA waste and creates new opportunities for green synthesis of amino acids., (© 2024 Wiley‐VCH GmbH.)

The lifetime of electronic coherences found in photosynthetic antennas is known to be too short to match the energy transfer time, rendering the coherent energy transfer mechanism inactive. Exciton-vibrational coherence time in excitonic dimers which consist of two chromophores coupled by excitation transfer interaction, can however be much longer. Uncovering the mechanism for sustained coherences in a noisy biological environment is challenging, requiring the use of simpler model systems as proxies. Here, via two-dimensional electronic spectroscopy experiments, we present compelling evidence for longer exciton-vibrational coherence time in the allophycocyanin trimer, containing excitonic dimers, compared to isolated pigments. This is attributed to the quantum phase synchronization of the resonant vibrational collective modes of the dimer, where the anti-symmetric modes, coupled to excitonic states with fast dephasing, are dissipated. The decoupled symmetric counterparts are subject to slower energy dissipation. The resonant modes have a predicted nearly 50% reduction in the vibrational amplitudes, and almost zero amplitude in the corresponding dynamical Stokes shift spectrum compared to the isolated pigments. Our findings provide insights into the mechanisms for protecting coherences against the noisy environment., (© 2024. The Author(s).)

Parametric superfluorescence (PSF), which originated from the optical amplification of vacuum quantum noise, is the primary noise source of femtosecond fluorescence non-collinear optical parametric amplification spectroscopy (FNOPAS). It severely affects the detection limit of FNOPAS to collect the femtosecond time-resolved spectra of extremely weak fluorescence. Here, we report the development of femtosecond fluorescence conical optical parametric amplification spectroscopy (FCOPAS), aimed at effectively suppressing the noise fluctuation from the PSF background. In contrast to traditional FNOPAS configurations utilizing lateral fluorescence collection and dot-like parametric amplification, FCOPAS employs an innovative conical fluorescence collection and ring-like amplification setup. This design enables effective cancellation of noise fluctuation across the entire PSF ring, resulting in an approximate order of magnitude reduction in PSF noise compared to prior FNOPAS outcomes. This advancement enables the resolution of transient fluorescence spectra of 4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran (DCM) dye molecules in ethanol, even at an optically dilute concentration of 10-6 mol/l, with significantly enhanced signal-to-noise ratios. This improvement will be significant for extremely weak fluorescence detection on the femtosecond time scale., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Compared to fluctuating soil water (FW) conditions, stable soil water (SW) can increase plant water use efficiency (WUE) and improve crop growth and aboveground yield. It is unknown, however, how stable and fluctuating soil water affect root vegetables. Here, the effects of SW and FW were studied on cherry radish in a pot experiment, using negative pressure irrigation and conventional irrigation, respectively. The assessed effects included agronomic parameters, physiological indices, yield, quality and WUE of cherry radish. Results showed that under similarly average soil water contents, compared with FW, SW increased plant photosynthetic rate, stomatal conductance and transpiration rate, decreased leaf proline content by 13.7-73.3% and malondialdehyde content by 12.5-40.0%, and increased soluble sugars content by 6.3-22.1%. Cherry radish had greater biomass accumulation and nutrient uptake in SW than in FW. Indeed, SW increased radish output by 34.6-94.1% with no influence on root/shoot ratio or root quality. In conclusion, soil water stability affected directly the water physiological indicators of cherry radish and indirectly its agronomic attributes and nutrient uptake, which in turn influenced the crop biomass and yield, as well as WUE. This study provides a new perspective for improving agronomy of root crops and WUE through managing soil water stability., Competing Interests: Author GZ was employed by the company Beijing Liangxiang Lanxin Hydraulic Engineering & Design Co., Ltd. The remaining 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 © 2024 Li, Zhu, Liu, Wang, Long, Zhang and Yu.)

Solar hydrogen production at a high efficiency holds the significant importance in the age of energy crisis, while the micro-environment manipulation of active sites on photocatalysts plays a profound role in enhancing the catalytic performance. In this work, a series of well-defined single-site Ni-grafted TiO 2 photocatalysts with unique and specific coordination environments, 2,2'-bipyridine-Ni-O-TiO 2 (T-Ni Bpy) and 2-Phenylpyridine-Ni-O-TiO 2 (T-Ni Phpy), were constructed with the methods of surface organometallic chemistry combined with surface ligand exchange for visible-light-induced photocatalytic hydrogen evolution reaction (HER). A prominent rate of 33.82 μmol ⋅ g -1  ⋅ h -1 and a turnover frequency of 0.451 h -1 for Ni are achieved over the optimal catalyst T-Ni Bpy for HER, 260-fold higher than those of Ni-O-TiO 2 . Fewer electrons trapped oxygen vacancies and a larger portion of long-lived photogenerated electrons (>3 ns, ~52.9 %), which were demonstrated by the electron paramagnetic resonance and femtosecond transient IR absorption, correspond to the photocatalytic HER activity over the T-Ni Bpy. The number of long-lived free electrons injected from the Ni photoabsorber to the conduction band of TiO 2 is one of the determining factors for achieving the excellent HER activity., (© 2023 Wiley-VCH GmbH.)

Few nursing informatics studies focus on selecting nursing diagnoses for critical patients. The absence of data about nursing clinical judgment in the care of patients with cerebral hemorrhage greatly hinders research progress in evidence-based care. A stratified, retrospective study analyzed 115 electronic "intelligent" nursing information system nurse assessments and nursing diagnoses. Data were documented from April 2019 to November 2020 for critically ill patients admitted with cerebral hemorrhage in a 10-bed medical ICU at a 1500-bed tertiary facility, Henan Honliv Hospital, in Henan Province, China. In the selection of nursing diagnoses among nurses of stratified competencies (novice to expert), novice and experienced nurses were found to have significant variances in selecting nursing diagnoses for critically ill patients with cerebral hemorrhage. Novice nurses more frequently selected the Activity Intolerance Risk diagnosis as an initial diagnosis ( P = .025). Experienced nurses selected the Fluid Volume Excess Risk diagnosis more frequently ( P = .003). Consequently, nursing information systems are important in evaluating professional practice. The access to structured, standardized nursing data for the complete nursing process enables nurse managers to comprehensively analyze the nursing care given to patients, the distribution of patient nursing diagnoses, and the status of patient care risks., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

The major light-harvesting complex of photosystem II (LHCII) has a dual regulatory function in a process called non-photochemical quenching to avoid the formation of reactive oxygen. LHCII undergoes reversible conformation transitions to switch between a light-harvesting state for excited-state energy transfer and an energy-quenching state for dissipating excess energy under full sunshine. Here we report cryo-electron microscopy structures of LHCII in membrane nanodiscs, which mimic in vivo LHCII, and in detergent solution at pH 7.8 and 5.4, respectively. We found that, under low pH conditions, the salt bridges at the lumenal side of LHCII are broken, accompanied by the formation of two local α-helices on the lumen side. The formation of α-helices in turn triggers allosterically global protein conformational change, resulting in a smaller crossing angle between transmembrane helices. The fluorescence decay rates corresponding to different conformational states follow the Dexter energy transfer mechanism with a characteristic transition distance of 5.6 Å between Lut1 and Chl612. The experimental observations are consistent with the computed electronic coupling strengths using multistate density function theory., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Several dumbbell conjugates featuring M 3 N@ I h -C 80 (M = Sc, Y) and C 60 were prepared to systematically investigate interfullerene electronic interactions and excited state dynamics. From electrochemical investigations, we concluded that the redox potentials of our M 3 N@ I h -C 80 (M = Sc, Y) dumbbells depend largely on the interfullerene electronic interactions. Assisted by DFT calculation, the unique role of metal atoms was highlighted. Most importantly, ultrafast spectroscopy experiments revealed symmetry-breaking charge separation in Sc 3 N@C 80 -dumbbell to yield an unprecedented (Sc 3 N@C 80 ) •+ -(Sc 3 N@C 80 ) •- charge separated state. This is, to the best of our knowledge, the first time that symmetry-breaking charge separation following photoexcitation is corroborated in a fullerene system. As such, our work shed light on the significance of interfullerene electronic interactions and their uniqueness for modulating excited state properties.

Due to the strong Coulomb interaction, the optical and electrical properties of two-dimensional transition metal dichalcogenides (TMDCs) are greatly determined by the emergence of many-body complexes such as excitons or trions. To fully realize the potential functionalities of these atomically thin materials, a comprehensive understanding of their many-body interaction mechanism is essential. Here, using the advanced femtosecond two-dimensional electronic spectroscopy technique combined with broadband transient absorption spectroscopy, a strong electron-exciton coupling effect in monolayer WSe 2 following the ultrafast photoexcitation is revealed. We demonstrate that such many-body complexes can be generated effectively through the band-edge optical excitation, with a ∼1.5 ps stabilization process. The coherent optical phonon plays a dominant role in this electron-exciton interaction, and the coherence of the electron (exciton)-phonon coupling can last for ∼4.5 ps. This finding offers new insight into the formation mechanism of photoinduced many-body complexes in TMDCs.

All-solid-state Z-Scheme photocatalysts have attracted significant attention due to their great potential for solar fuel production. However, delicately coupling two individual semiconductors with a charge shuttle by a material strategy remains a challenge. Herein, we demonstrate a new protocol of natural Z-Scheme heterostructures by strategically engineering the component and interfacial structure of red mud bauxite waste. Advanced characterizations elucidated that the hydrogen-induced formation of metallic Fe enabled the effective Z-Scheme electron transfer from γ-Fe 2 O 3 to TiO 2 , leading to the significantly boosted spatial separation of photo-generated carriers for overall water splitting. To the best of our knowledge, it is the first Z-Scheme heterojunction based on natural minerals for solar fuel production. Thus our work provides a new avenue toward the utilization of natural minerals for advanced catalysis applications., (© 2023 Wiley-VCH GmbH.)

In this work, ultrafast carrier dynamics of mechanically exfoliated 1T-TiSe 2 flakes from the high-quality single crystals with self-intercalated Ti atoms are investigated by femtosecond transient absorption spectroscopy. The observed coherent acoustic and optical phonon oscillations after ultrafast photoexcitation reveal the strong electron-phonon coupling in 1T-TiSe 2 . The ultrafast carrier dynamics probed in both visible and mid-infrared regions indicate that some photogenerated carriers localize near the intercalated Ti atoms and form small polarons rapidly within several picoseconds after photoexcitation due to the strong and short-range electron-phonon coupling. The formation of polarons leads to a reduction of carrier mobility and a long-time relaxation process of photoexcited carriers for several nanoseconds. The formation and dissociation rates of the photoinduced polarons are dependent on both the pump fluence and the thickness of TiSe 2 sample. This work offers new insights into the photogenerated carrier dynamics of 1T-TiSe 2 , and emphasizes the effects of intercalated atoms on the electron and lattice dynamics after photoexcitation., (© 2023 IOP Publishing Ltd.)

A series of novel surface Ru-H bipyridine complexes-grafted TiO 2 nanohybrids were for the first time prepared by a combined procedure of surface organometallic chemistry with post-synthetic ligand exchange for photocatalytic conversion of CO 2 to CH 4 with H 2 as electron and proton donors under visible light irradiation. The selectivity toward CH 4 increased to 93.4% by the ligand exchange of 4,4'-dimethyl-2,2'-bipyridine (4,4'-bpy) with the surface cyclopentadienyl (Cp)-RuH complex and the CO 2 methanation activity was enhanced by 4.4-fold. An impressive rate of 241.2 μL·g -1 ·h -1 for CH 4 production was achieved over the optimal photocatalyst. The femtosecond transient IR absorption results demonstrated that the hot electrons were fast injected in 0.9 ps from the photoexcited surface 4,4'-bpy-RuH complex into the conduction band of TiO 2 nanoparticles to form a charge-separated state with an average lifetime of ca. 50.0 ns responsible for the CO 2 methanation. The spectral characterizations indicated clearly that the formation of CO 2 •- radicals by single electron reduction of CO 2 molecules adsorbed on surface oxygen vacancies of TiO 2 nanoparticles was the most critical step for the methanation. Such radical intermediates were inserted into the explored Ru-H bond to generate Ru-OOCH species and finally CH 4 and H 2 O in the presence of H 2 .

Nitrate is an important raw material for chemical fertilizers, but it is industrially manufactured in multiple steps at high temperature and pressure, urgently motivating the design of a green and sustainable strategy for nitrate production. We report the photosynthesis of nitrate from N 2 and O 2 on commercial TiO 2 in a flow reactor under ambient conditions. The TiO 2 photocatalyst offered a high nitrate yield of 1.85 μmol h -1 as well as a solar-to-nitrate energy conversion efficiency up to 0.13 %. We combined reactivity and in situ Fourier transform infrared spectroscopy to elucidate the mechanism of nitrate formation and unveil the special role of O 2 in N≡N bond dissociation. The mechanistic insight into charge-involved N 2 oxidation was further demonstrated by in situ transient absorption spectroscopy and electron paramagnetic resonance. This work exhibits the mechanistic origin of N 2 photooxidation and initiates a potential method for triggering inert catalytic reactions., (© 2022 Wiley-VCH GmbH.)

Context: Urolithin A (UroA) can inhibit the growth of many human cancer cells, but it has not be reported if UroA inhibits nasopharyngeal carcinoma (NPC) cells., Objective: To explore the inhibitory effect of UroA on NPC and potential mechanism in vitro ., Materials and Methods: RNA-sequencing-based mechanistic prediction was conducted by comparing KEGG enrichment of 40 μM UroA-treated for 24 h with untreated CNE2 cells. The untreated cells were selected as control. After NPC cells were treated with 20-60 μM UroA, proliferation, migration and invasion of were measured by colony formation, wound healing and transwell experiments. Apoptosis, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) were measured by flow cytometry, Hoechst 33342, Rhodamine 123, JC-1 staining and ROS assay methods, respectively. Gene and protein expression were measured by RT-qPCR and Western blotting assay., Results: RNA-sequencing and KEGG enrichment revealed UroA mainly altered the ECM receptor interaction pathway. UroA inhibited cells proliferation, epithelial-mesenchymal-transition pathway, migration and invasion with IC 50 values of 34.72 μM and 44.91 μM, induced apoptosis, MMP depolarization and increase ROS content at a concentration of 40 μM. UroA up-regulated E-cadherin, Bax/Bcl-2, c-caspase-3 and PARP proteins, while inhibiting COL4A1, MMP2, MMP9, N-cadherin, Vimentin and Snail proteins at 20-60 μM. Moreover, co-treatment of UroA (40 μM) and NAC (5 mM) could reverse the effect of UroA on apoptosis-related proteins., Discussion and Conclusions: RNA-sequencing technology based on bioinformatic analyses may be applicable for studiying the mechanism of drugs for tumour treatment.

Background: Due to radical resection, endoprosthetic reconstruction (EPR) is more invasive and increases the risk of dislocation. Therefore, the suitability of EPR for elderly patients with metastatic tumor needs further investigation., Methods: Seventy-one adult patients with isolated proximal femoral bone metastases who underwent EPR were retrospectively analyzed and stratified into two groups: elderly age group (≥60 years, n = 31) and younger age group (<60 years, n = 40). The effect of age on prognosis was analyzed to determine whether EPR is beneficial in elderly patients with proximal femoral metastatic tumor. Cox regression modeling was used to evaluate the effect of different factors on postoperative survival outcomes., Results: Ten (32.26%) and 9 (22.50%) cases of perioperative complications were recorded in the elderly and younger age groups, respectively, with median survival times of 22.00 ± 4.61 months and 23.00 ± 2.85 months, respectively; a log-rank test showed that the difference was not statistically significant (p = 0.657). A Cox regression model was established with patient age as the covariable to evaluate whether it affected postoperative survival. The risk of death due to age was not significant (p = 0.649), but malignancy and femoral metastasis type were significantly associated with postoperative survival (p = 0.001 and p = 0.019)., Conclusion: Although older patients have a slightly higher incidence of postoperative complications than younger patients, they do not experience severe adverse consequences. With rigorous selection and careful preparation, EPR is appropriate for the treatment of proximal femoral metastases in older patients, including those with Harrington type I-II acetabular invasion., (© 2022. Society of Surgical Oncology.)

The rhodopsin mimic is a chemically synthetized complex with retinyl Schiff base (RSB) formed between protein and the retinal chromophore that can mimic the natural rhodopsin-like protein. The artificial rhodopsin mimic is more stable and designable than the natural protein and hence has wider uses in photon detection devices. The mimic structure RSB, like the case in the actual rhodopsin-like protein, undergoes isomerization and protonation throughout the photoreaction process. As a result, understanding the dynamics of the RSB in the photoreaction process is critical. In this study, the ultrafast transient absorption spectra of three mutants of the cellular retinoic acid-binding protein II-based rhodopsin mimic at acidic environment were recorded, from which the related excited-state dynamics of the all-trans protonated RSB (AT-PRSB) were investigated. The transient fluorescence spectra measurements are used to validate some of the dynamic features. We find that the excited-state dynamics of AT-PRSB in three mutants share a similar pattern that differs significantly from the dynamics of 15-cis PRSB of the rhodopsin mimic in neutral solution. By comparing the dynamics across the three mutants, we discovered that the aromatic residues near the β-ionone ring structure of the retinal may help stabilize the AT-PRSB and hence slow down its isomerization rate. The experimental results provide implications on designing a rhodopsin-like protein with significant infrared fluorescence, which can be particularly useful in the applications in biosensing or bioimaging in deeper tissues., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022. Published by Elsevier Inc.)

Objective: MicroRNA (miRNA/miR)-633 is dysregulated in several types of cancers and is involved in tumorigenesis. However, the function and role of this miRNA in gastric cancer (GC) are not fully understood. The aim of the present study was to evaluate miR-633 expression in GC cell lines and in GC tissue vs. adjacent normal tissue, and to determine its association with clinicopathological data. This work was extended to investigate the effects of miR-633 overexpression on tumor cells in vitro., Methods: Reverse transcription-quantitative PCR (RT-qPCR) was used to detect and compare the expression level of miR-633 in GC cells, as well as in GC and normal adjacent tissue samples. The clinical significance of miR-633 was also analyzed. MiR-633 lentivirus (LV-miR-633) and negative control lentivirus (LV-NC) were generated and used to transduce SGC-7901 and HGC-27 GC cells in order to analyze the effect of miR-633 on their phenotype. The effects of miR-633 overexpression on GC cell proliferation, apoptosis, migration and invasion were investigated. The target gene of miR-633 was predicted, then confirmed using a dual luciferase reporter gene assay, RT-qPCR and Western blotting., Results: MiR-633 was significantly downregulated in GC cell lines, as well as in GC tissue compared with adjacent normal tissue. Moreover, miR-633 expression was associated with the tumor/node/metastasis (TNM) stage, invasion depth, Borrmann classification and lymph node metastasis (P<0.05). Compared with the LV-NC group, transduction with LV-miR-633 reduced the proliferation, the number of clones, the wound healing rate, the number of invading cells and the number of cells in the G 1 phase of the cell cycle (P<0.01). LV-miR-633 also increased the apoptosis rate (P<0.01). The expression level of mitogen-activated protein kinase (MAPK) 1, high-mobility group box 3 (HMGB3), claudin 1 (CLDN1) and MAPK13 were downregulated in LV-miR-633-transduced cells (P<0.01). The dual luciferase reporter assay confirmed that the 3'-untranslated region of MAPK1 was the target site of miR-633 (P<0.01)., Conclusion: MiR-633 acts as a tumor suppressor in GC, and its expression level is associated with TNM stage, invasion depth, Borrmann type and lymph node metastasis. Overexpression of miR-633 inhibits the proliferation and migration of GC cells and induces apoptosis and cell cycle arrest at the in G 1 phase. In addition, miR-633 negatively regulates the expression of MAPK1, HMGB3, CLDN1 and MAPK13 and directly targets MAPK1., (© 2022. Huazhong University of Science and Technology.)

Ferroelectrics are considered excellent photocatalytic candidates for solar fuel production because of the unidirectional charge separation and above-gap photovoltage. Nevertheless, the performance of ferroelectric photocatalysts is often moderate. A few studies showed that these types of photocatalysts could achieve overall water splitting. This paper proposes an approach to fabricating interfacial charge-collecting nanostructures on positive and negative domains of ferroelectric, enabling water splitting in ferroelectric photocatalysts. The present study observes efficient accumulations of photogenerated electrons and holes within their thermalization length (~50 nm) around Au nanoparticles located in the positive and negative domains of a BaTiO 3 single crystal. Photocatalytic overall water splitting is observed on a ferroelectric BaTiO 3 single crystal after assembling oxidation and reduction cocatalysts on the positively and negatively charged Au nanoparticles, respectively. The fabrication of bipolar charge-collecting structures on ferroelectrics to achieve overall water splitting offers a way to utilize the energetic photogenerated charges in solar energy conversion., (© 2022. The Author(s).)

Weaker temporal variation of soil moisture can improve crop water use efficiency (WUE), but its physiological mechanism was still unclear. To explore the mechanism, an organized experiment was conducted in Beijing from June to September. From the jointing stage to maturity stage of maize, stable soil moisture (SSM) and fluctuating soil moisture (FSM) were established with Pressure Potential Difference-Crop Initiate Drawing Water (PCI) and manual irrigation (MI), respectively, to explore the physiological mechanism of SSM to improve maize WUE. Among them, PCI treatments were set with 3 pressure differences of -5, -10, and -15 kPa, and MI treatment was watering every 3 days with the irrigation amount of 9.3 mm. The results showed that (1) after water treatment, the average soil water content of PCI-5 kPa, PCI-10 kPa, PCI-15 kPa, and MI treatments were 53% field capacity (FC), 47, 38, and 78% FC, respectively. It was SSM with weak temporal variation under PCI treatments, and FSM with medium temporal variation under MI treatment. (2) PCI treatments reduced the content of proline, malondialdehyde, and abscisic acid in each organ of maize. (3) Compared with FSM 78% FC, the maize root activity at the filling stage of 53% FC SSM and 47% FC SSM increased significantly by 57.1 and 28.6%, respectively, and the carbon isotope discrimination value (Δ 13 C) in bracts of the two treatments increased by 18.3 and 10.4%, respectively. (4) There was a very significant positive correlation between WUE based on biomass (WUE b ) and Δ 13 C in bracts. In conclusion, a large temporal variation of soil moisture was an important factor that caused water stress in maize. Under SSM treatments, the accumulation of abscisic acid, proline, and malondialdehyde was synergistically reduced. SSM improved the WUE of maize by alleviating short-term soil water stress caused by the fluctuation of soil moisture., Competing Interests: GZ was employed by Beijing Liangxiang Lanxin Hydraulic Engineering & Design Co., Ltd. The remaining 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 Niu, Wang, Zhu, Yu, Li and Long.)

The presence of quantum coherence in light-harvesting complex II (LHCII) as a mechanism to understand the efficiency of the light-harvesting function in natural photosynthetic systems is still debated due to its structural complexity and weak-amplitude coherent oscillations. Here, we revisit the coherent dynamics and clarify different types of coherences in the energy transfer processes of LHCII using a joint method of the high-S/N transient grating and two-dimensional electronic spectroscopy. We find that the electronic coherence decays completely within 50 fs at room temperature. The vibrational coherences of chlorophyll a dominate over oscillations within 1 ps, whereas a low-frequency mode of 340 cm -1 with a vibronic mixing character may participate in vibrationally assisted energy transfer between chlorophylls a. Our results may suggest that vibronic mixing is relevant for rapid energy transfer processes among chlorophylls in LHCII.

Background: The constitutive centromere associated network (CCAN) complex played a critical role in connecting the centromere with the mitotic spindle during mitosis and meiosis. Many studies have indicated that CCAN is related to the tumorigenesis and cancer development. Nonetheless, the overview of CCAN gene family in pan-cancer remain incompletely understood., Methods: We performed a comprehensive investigation on pan-cancer impacts of CCAN by integrating multi-omics data. We comprehensively investigated the expression profile, kyoto encyclopedia of genes and genomes (kegg) pathway, mutation, copy number variation, tumor microenvironment, immune cells infiltration, and drug sensitivity of CCAN in pan-cancer. MRNA expression profiles were collected from the cancer genome atlas, oncomine and ccle, the differential expression and various relevance analysis were performed with R or Perl., Results: The results showed that the expression of CCAN was different in 33 tumors. Intriguingly, the poor survival in adrenocortical carcinoma, cholangiocarcinoma, kidney chromophobe, mesothelioma, kidney renal clear cell carcinoma, brain lower grade glioma, pheochromocytoma and paraganglioma, prostate adenocarcinoma, thyroid carcinoma, uveal melanoma was most likely related to the kegg single transduction pathway including one carbon pool by folate, proteasome, arachidonic acid metabolism and so on. CENPC, ITGB3BP, APITD1, CENPU, and CENPW were more involved in tumor microenvironment, which more likely related to NK cells resting, T cells follicular helper, T cells CD8, neutrophils, macrophages M0, T cells CD4 memory activated. The relationship of CCAN expression with drug sensitivity showed that chelerythrine, nelarabine, and hydroxyurea maybe be potential drugs., Conclusions: This multidimensional study provides a valuable resource to assist mechanism research and clinical utility about CCAN., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.)

Semiconductor saturable absorber mirrors (SESAMs) have been regarded as a revolutionary technology for ultrafast mode-locked lasers, producing numerous landmark laser breakthroughs. However, the operating wavelength of existing SESAMs is limited to less than 3 µm. In this study, we create a 3-5 µm mid-infrared (MIR) SESAM by engineering an InAs/GaSb type-II superlattice. Bandgap engineering and the strong coupling between potential wells in a superlattice enable a broadband response of saturable absorption in the 3-5 µm spectral range. Using the fabricated SESAM, we realize a SESAM mode-locked Er:ZBLAN fiber laser at 3.5 µm, which delivers MIR ultrashort pulses with high long-term stability. The breakthrough of SESAM fabrication in the MIR will promote the development of MIR ultrafast coherent sources and related application fields.

Objective: The genetic markers for the detection or treatment of cervical squamous cell carcinoma (CESC) are not yet complete. This study aimed to identify the role of MSMO1 (Alternative name: SC4MOL) in the occurrence and development of CESC. Methods: We evaluated the significance of MSMO1 expression in CESC by using analysis of a public dataset from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database. Oncomine and GEPIA2 were used to validate MSMO1 as an independent prognostic factor in CESC. Multiple tools were used to analyze the factors and functions associated with MSMO1, such as methylation, miRNA, and co-expressed genes. Furthermore, TIMER and TISIDB were used to study the relationship between MSMO1 expression and immunization in CESC. Results: MSMO1 was highly expressed in tumor specimens and could be used as an independent prognostic factor of CESC ( p < 0.05). But Casiopeinas chemotherapeutics and p63 loss could reduce the expression of MSMO1. The level of methylation MSMO1 was significantly increased in tumor tissues but there was an insignificant effect on the prognosis. MSMO1 was also closely related to hsa-miR-23a-3p, hsa-miR-23b-3p, hsa-miR-130b-3p, and gene IDI1. Specifically, the expression level of MSMO1 had a significant negative correlation with the infiltration level of CD4 + T cells, Macrophages, Neutrophils, and DCs in CESC. In addition, GSEA identified differential enrichment in systemic lupus erythematosus, vascular smooth muscle contraction, cytokine receptor interaction, focal adhesion, chemokine signaling pathway, and Leishmania infection pathway in KEGG. Conclusion: Our findings provide evidence of the implications of MSMO1 in tumors, suggesting that MSMO1 is a promising prognostic biomarker in CESC., 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 Zheng, Wang, Fan, Wang, Zhang, Wang, Chen and Jiang.)

Objective: The concept of enhanced recovery after surgery (ERAS) has been proposed to provide guidance for the improved postoperative rehabilitation of patients with occipitocervical region disease (ORD)., Methods: This study retrospectively investigated 208 consecutive patients (116 men and 92 women) ranging in age from 22 to 76 years with ORD between July 2014 and June 2017 in our medical center, who were divided into three groups that received different preoperative, intraoperative, and postoperative management plans: traditional group (n = 73), ameliorated group (n = 70), and ERAS group (n = 65). We compiled a range of data relating to demographics and postoperative changes in hemoglobin and albumin, surgery duration, intraoperative blood loss, number of postoperative hospitalization days and expenses, readmission rates, and visual analog scale pain symptoms. Data were statistically evaluated using one-way analysis of variance with Student-Newman-Keuls-q post hoc tests or chi-square tests., Results: There were no significant differences in terms of age (P = 0.235), gender (P = 0.691), body mass index (P = 0.723), American Society of Anesthesiologists grade (0.747), lesion character (P = 0.337) and lesion site (P = 0.957) between the three groups. Within a 6 months follow-up period, there was no significant difference between the three groups in terms of surgery duration (P = 0.225), blood loss (P = 0.172), changes in hemoglobin (P = 0.255) and albumin (P = 0.178). However, postoperative hospitalization days (P = 0.000), postoperative costs (P = 0.019) and improvement of pain symptoms (P = 0.000) in ERAS group were significantly lower or higher than those in traditional group or ameliorated group, respectively. There were 29 (39.73%), 22 (31.43%), and 13 (20.00%), recorded cases of postoperative complications in traditional group, ameliorated group and ERAS group, respectively; complications in ERAS group were significantly lower than those in other two groups (P = 0.043). Moreover, all of the complications were mitigated effectively by the infusion of fluid, analgesia, treatment of infections, or antiemetic medications. There were 2 (2.74%), 3 (4.29%) and 2 (3.08%), recorded cases of re-admission in traditional group, ameliorated group and ERAS group, respectively, but there were no statistically significant differences when compared across the three groups (P = 0.866)., Conclusions: ERAS can provide benefits when it applied to patients undergoing ORD surgery mainly in terms of reducing postoperative complications, however, ERAS does not increase the economic burden of patients or decrease the risk of readmission., (© 2021 The Authors. Orthopaedic Surgery published by Chinese Orthopaedic Association and John Wiley & Sons Australia, Ltd.)

This study was aimed at constructing a self-nanoemulsifying drug delivery system of buckwheat flavonoids and evaluating its antimicrobial activity. The construction of the nanoemulsion followed a pseudo-ternary phase diagram, and its particle properties (particle size, zeta potential, and surface morphology) and physicochemical parameters (turbidity, surface tension, pH value, conductivity, encapsulation efficiency, and stability) were evaluated. The antimicrobial potential of buckwheat flavonoids nanoemulsion was determined against Staphylococcus aureus, Escherichia coli, and Candida albicans and compared to the buckwheat flavonoids suspension. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) exhibited that the antimicrobial activity of the nanoemulsions and suspension increased while enhancing the drug concentration, and the antimicrobial activity of nanoemulsion was significantly higher than that of the suspension against those three bacteria. Agar disc diffusion test demonstrated that the inhibition zone diameter of the suspension was about 50% of the nanoemulsion against three bacteria. The time killing assay indicated that the IC 50 of the nanoemulsion was significantly lower than that of the suspension. These results indicate that nanoemulsion is a promising drug delivery system, which can improve the antimicrobial activity of buckwheat flavonoids.

Objective: To systematically evaluate the efficacy and safety of levetiracetam (LEV) versus phenytoin (PHT) as second-line drugs for the treatment of convulsive status epilepticus (CSE) in children., Methods: English and Chinese electronic databases were searched for the randomized controlled trials comparing the efficacy and safety of LEV and PHT as second-line drugs for the treatment of childhood CSE. RevMan 5.3 software was used for data analysis., Results: Seven studies with 1 434 children were included. The Meta analysis showed that compared with the PHT group, the LEV group achieved a significantly higher control rate of CSE ( RR =1.12, 95% CI :1.00-1.24, P =0.05), but there was no significant difference between the two groups in the recurrence rate of epilepsy within 24 hours ( RR =0.82, 95% CI :0.22-3.11, P =0.77) and the rate of further antiepileptic drug therapy ( RR =0.97, 95% CI :0.64-1.45, P =0.87). There was no significant difference in the incidence rate of adverse events between the two groups ( RR =0.77, 95% CI :0.55-1.09, P =0.15)., Conclusions: LEV has a better clinical effect than PHT in the treatment of children with CSE and does not increase the incidence rate of adverse events.

Cu 2 O, a low-cost, visible light responsive semiconductor photocatalyst represents an ideal candidate for visible light driven photocatalytic reduction of N 2 to NH 3 from the viewpoint of thermodynamics, but it remains unexplored. Reported here is the successful synthesis of uniformly sized and ultrafine Cu 2 O platelets, with a lateral size of <3 nm, by the in situ topotactic reduction of a Cu II -containing layered double hydroxide with ascorbic acid. The supported ultrafine Cu 2 O offered excellent performance and stability for the visible light driven photocatalytic reduction of N 2 to NH 3 (the Cu 2 O-mass-normalized rate as high as 4.10 mmol g Cu 2 O -1  h -1 at λ>400 nm), with the origin of the high activity being long-lived photoexcited electrons in trap states, an abundance of exposed active sites, and the underlying support structure. This work guides the future design of ultrafine catalysts for NH 3 synthesis and other applications., (© 2020 Wiley-VCH GmbH.)

This study examines the impact of air pollution on research and development (R&D) in China on the basis of province-level data for the period 2007-2016. The study discovers a significant adverse impact of air pollution on both R&D input and output in China. The estimation results in this study are robust to the different indicators used to measure R&D input and output and control for possible endogeneity problems via the instrumental variable approach. According to our estimates, if the concentration of particulate matter with a diameter of 2.5 μm or less (PM 2.5 ) increases by 1%, then the scales of annual R&D personnel, expenditures, and new patents will decline by 0.359%, 0.169%, and 0.293%, respectively. The findings indicate that air pollution is a considerable threat to innovation and technological progress in China., Competing Interests: Declaration of competing interest 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., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Metal halide perovskites with direct band gap and strong light absorption are promising materials for harvesting solar energy; however, their relatively narrow band gap limits their redox ability when used as a photocatalyst. Adding a second semiconductor component with the appropriate band structure offsets can generate a Z-scheme photocatalytic system, taking full advantage of the perovskite's intrinsic properties. In this work, we develop a direct Z-scheme photocatalyst based on formamidinium lead bromide and bismuth tungstate (FAPbBr 3 /Bi 2 WO 6 ) with strong redox ability for artificial solar-to-chemical energy conversion. With desirable band offsets and strong joint redox potential, the dual photocatalyst is shown to form a semicoherent heterointerface. Ultrafast transient infrared absorption studies employing selective excitation reveal synergetic photocarrier dynamics and demonstrate Z-scheme charge transfer mechanisms. Under simulated solar irradiation, a large driving force photoredox reaction (∼2.57 eV) of CO 2 reduction coupled with benzyl alcohol oxidation to benzaldehyde is achieved on the Z-scheme FAPbBr 3 /Bi 2 WO 6 photocatalyst, harnessing the full synergetic potential of the combined system.

The difference between the excited- and ground-state vibrational wavepackets remains to be fully explored when multiple vibrational modes are coherently excited simultaneously by femtosecond pulses. In this work, we present a series of one- and two-dimensional electronic spectroscopy for studying multimode wavepackets of oxazine 720 in solution. Fourier transform (FT) maps combined with time-frequency transform (TFT) are employed to unambiguously distinguish the origin of low-frequency vibrational wavepackets, that is, an excited-state vibrational wavepacket of 586 cm -1 with a dephasing time of 0.7 ps and a ground-state vibrational wavepacket of 595 cm -1 with a dephasing time of 1.3-1.7 ps. We also found the additional low-frequency vibrational wavepackets resulting from the coupling of the 595 cm -1 mode to a series of high-frequency modes centered at 1150 cm -1 via electronic transitions. The combined use of FT maps and TFT analysis allows us to reveal the potential vibrational coupling of wavepackets and offers the possibility of disentangling the coupling between the electronic and vibrational degrees of freedom in condensed-phase systems.

Novel fullerene-based donor-acceptor (DA) dyads, Sc 3 N@C 80 -PTZ and C 60 -PTZ, have been synthesized and investigated in which the photoinduced electron transfer direction is proved to be switchable by regulating the redox state. In detailed photophysical experiments, reductive electron transfer from the PTZ moiety to Sc 3 N@C 80 is confirmed with transient absorption (TA) spectroscopy in the neutral Sc 3 N@C 80 -PTZ dyad. After oxidizing the PTZ moiety to PTZ •+ in a reversible manner, oxidative electron transfer from the Sc 3 N@C 80 moiety to the PTZ •+ radical cation is corroborated experimentally and theoretically, leading to formation of a metastable charge transfer (CT) state (Sc 3 N@C 80 ) •+ -PTZ, which is not observed in the C 60 -PTZ •+ dyad. To the best of our knowledge, this is the first time in situ tunable molecular photodiode-like behavior is fulfilled utilizing a fullerene dyad. These findings will contribute to the future application of fullerene-based DA conjugates in molecular electronic devices.

Size-controlled and high-index faceted α-Fe 2 O 3 nanocrystals with pseudocubic and rhombohedral morphologies were synthesized through the hydrothermal treatment of β-FeOOH at different pHs. The size effect on the photocatalytic oxygen evolution efficiency of high-index faceted α-Fe 2 O 3 nanocrystals was investigated. Rhombohedral α-Fe 2 O 3 (pH 6.0) exhibits an outstanding apparent quantum yield of 9.93% and an oxygen evolution efficiency of 20.3%, which can be attributed to the optimal size and high-indexed {104} planes. This work provides a new idea for the design of high activity water oxidation catalysts, through the size optimization of high-index faceted materials., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

By virtue of the quantum confinement effect, the junction between black phosphorus and red phosphorus changes from a type I heterostructure for bulk materials to a Z-scheme system for quantum dots. The Z-scheme system of black/red phosphorus quantum dots (BP/RP-QD) achieves H 2 evolution from water splitting in the absence of sacrificial agents.

Black phosphorus (BP) has recently drawn attention in photocatalysis for its optical properties. However, limited by the rapid recombination of photogenerated carriers, the use of BP for photocatalytic water splitting still remains a huge challenge. Herein, we prepare a black/red phosphorus (BP/RP) hetero-phase junction photocatalyst by a wet-chemistry method to promote the interfacial charge separation and thus achieve Z-scheme photocatalytic water splitting without using sacrificial agents. The Z-scheme mechanism was confirmed by time-resolved transient absorption spectroscopy. This work provides a novel insight into the interface design of hetero-phase junction with atomic precision., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Colloid-synthesized matchstick-shaped Au-ZnO heterogeneous nanorods are found to have the Zn ion terminated plane in the ZnO-Au interface without the formation of Au-O bonds based on the atomic-resolution observation of their interfacial structure and electronic states, which is greatly different from the other reported results. The Au-ZnO heterogeneous nanorods with a good expitaxial interface have shown a stronger surface-enhanced Raman scattering (SERS) signal of the dopamine molecules than Au nanoscale seeds alone, which is attributed to the enhanced charge transfer (CT) effect of ZnO which is greatly improved by the plasmon-induced hot electron from Au nanostructures. The enhanced CT effect has also been proved by a higher photocatalysis efficiency. Furthermore, the plasmon-induced hot electron transfer mechanism in Au-ZnO heterogeneous nanorods has been confirmed by a slow rise time of electrons in the transient absorption measurements. These findings suggest the dependency of the plasmon-induced hot electron transfer mechanism on the different mixing of the metal and semiconductor band levels.

Unlike the probe wavelength, which is spectrally resolved by monochromator, the excitation wavelength in two-dimensional electronic spectroscopy is retrieved by means of Fourier transform of the interference signal introduced by the coherence delay time between the first and second excitation laser pulses. Hence, the calibration of delay lines would determine its accuracy. In this work, we showed that an inaccurate calibration factor of wedge-based delay line would result in a global peak shift and asymmetric spectral twists along the excitation axis. Both theoretical analysis and experiments have shown that such spectral distortions can be corrected by an accurately predetermined calibration factor. The relative accuracy of calibration factor reaches 3 × 10 -5 in our setup. The dispersion effect of wedges also has been considered for the broadband excitation.

The features of the electronic structure of semiconductor photocatalysts are fundamental to understanding the corresponding photocatalytic process. Besides the bandgap and edges, the behavior of photogenerated charge carriers and trap states can also greatly affect the photocatalytic process but it has been less considered during the material design. A previous study (G. Liu, J. Pan, L. Yin et al., Adv. Funct. Mater., 2012, 22, 3233-3238) showed that the interstitial boron on anatase {001} facets can change the photocatalytic preference from reductive H2 evolution to oxidative O2 evolution in the water splitting reaction, interpreted as the change in the band edges. In this work, we employed transient infrared absorption-excitation energy scanning spectroscopy and femtosecond time-resolved mid-infrared spectroscopy to investigate this phenomenon in view of the effect caused by the boron dopant on the photogenerated carrier kinetics and the energy level distribution of the trap states. We found that the surface boron doping eliminates significantly the trap states above the valence band, which improves its photocatalytic oxygen generation. On the other hand, surface boron doping also introduces a substantial amount of electron recombination centers (i.e., Bσ+ in the shell layer). Furthermore, surface boron doping also leads to an inefficient electron transfer from TiO2 to the co-catalyst Pt. Both of these effects give rise to its inferior photocatalytic capability in H2 evolution.

Plasmons in conducting nanostructures offer the means to efficiently manipulate light at the nanoscale with subpicosecond speed in an all-optical operation fashion, thus allowing for construction of high performance all-optical signal-processing devices. Here, by exploiting the ultrafast nonlinear optical properties of broadly tunable mid-infrared (MIR) plasmons in solution-processed, degenerately doped oxide nanoparticles, we demonstrate ultrafast all-optical switching in the MIR region, which features subpicosecond response speed (with recovery time constant of <400 fs) as well as an ultrabroadband response spectral range (covering 3.0-5.0 μm). Furthermore, with the degenerately doped nanoparticles as Q-switch, pulsed fiber lasers covering 2.0-3.5 μm were constructed, of which a watt-level fiber laser at 3.0 μm band shows superior overall performance among previously reported passively Q-switched fiber lasers at the same band. Notably, the degenerately doped nanoparticles show great potential to work in the spectral range over 3.0 μm, which is beyond the accessibility of commercially available but expensive semiconducting saturable absorber mirror (SESAM). Our work demonstrates a versatile while cost-effective material solution to ultrafast photonics in the technologically important MIR region.

Lariciresinol (LA) is one of the main active ingredients in many traditional medicinal plants such as Patrinia, and has the role of anti-liver cancer. However, the precise mechanisms are unclear. This study investigated the molecular mechanisms of LA against HepG2 cells. LA anti-tumor activity was assessed with the CCK-8, Ki-67, and immunofluorescence staining. Cells apoptotic ratio was evaluated by Annexin V/PI double-staining assay. A proteomic approach was used to identify differentially expressed proteins after LA treatment. JC-1 staining was carried out to detect the mitochondrial membrane potential (ΔΨm), and the Western blot analysis was used to analyse the apoptosis-associated proteins. Our results suggested that LA significantly suppressed the viability of HepG2 cells. The CCK-8 and Ki-67 expression indicated dose-dependent decreases in cell proliferation. Flow cytometry analysis showed that LA exhibited a apoptosis-inducing effect. The proteomic study observed the presence of apoptosis-associated proteins and mitochondrial dysfunction in HepG2 cells after LA-treatment. Further analysis showed that LA could trigger the mitochondrial-mediated apoptosis pathway, based on a decrease in ΔΨm; deliver of cytochrome c; activation of caspase-9/-3 and poly(ADP-ribose) polymerase; and decrease of the proportion of Bcl-2/Bax. Collectively, our studies found that LA exhibits significant cytotoxic effects by inhibiting cell proliferation, inducing apoptosis, possibly via activation of the mitochondrial-mediated apoptosis pathway., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Photocatalytic hydrogen evolution from pure water is successfully realized by using interstitial P-doped CdS with rich S vacancies (CdS-P) as the photocatalyst in the absence of any electron sacrificial agents. Through interstitial P doping, the impurity level of S vacancies is located near the Fermi level and becomes an effective electron trap level in CdS-P, which can change dynamic properties of photogenerated electrons and thus prolong their lifetimes. The long-lived photogenerated electrons are able to reach the surface active sites to initiate an efficient photocatalytic redox reaction. Moreover, the photocatalytic activity of CdS-P can be further improved through the loading of CoP as a cocatalyst., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Environmental change and human activity can be recorded in sediment cores in aquatic systems such as lakes. Information from such records may be useful for environmental governance in the future. Six sediment cores were collected from Lake Qinghai, China and its sublakes during 2012 and 2013. Measurements of sediment grain-size fractions indicate that sedimentation in the north and southwest of Lake Qinghai is dominated by river input, whereas that in Lake Gahai and Lake Erhai is dominated by dunes. The sedimentation rates in Lake Qinghai were calculated to be 0.101-0.159 cm/y, similar to the rates in other lakes on the Qinghai-Tibetan Plateau. Using these data and sedimentation rates from the literature, we compiled the spatial distribution of sedimentation rates. Higher values were obtained in the three main areas of Lake Qinghai: two in river estuaries and one close to sand dunes. Lower values were measured in the center and south of the lake. Measurements of total organic carbon (TOC), total nitrogen (TN), phosphorus concentrations, and TOC/TN ratios in three cores (QH01, QH02, and Z04) revealed four horizons corresponding to times of increased human activity. These anthropogenic events were (1) the development of large areas of cropland in the Lake Qinghai watershed in 1960, (2) the beginning of nationwide fertilizer use and increases in cropland area in the lake watershed after 1970, (3) the implementation of the national program "Grain to Green," and (4) the rapid increase in the tourism industry from 2000. Profiles of Rb, Sr concentrations, the Rb/Sr ratio, and grain-size fraction in core Z04 indicate that the climate has become drier over the past 100 years. Therefore, we suggest that lake sediments such as those in Lake Qinghai are useful media for high-resolution studies of regional environmental change and human activity.

While the majority of the photochemical states and pathways related to the biological capture of solar energy are now well understood and provide paradigms for artificial device design, additional low-energy states have been discovered in many systems with obscure origins and significance. However, as low-energy states are naively expected to be critical to function, these observations pose important challenges. A review of known properties of low energy states covering eight photochemical systems, and options for their interpretation, are presented. A concerted experimental and theoretical research strategy is suggested and outlined, this being aimed at providing a fully comprehensive understanding., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Superfluorescence appears as an intense background in femtosecond time-resolved fluorescence noncollinear optical parametric amplification spectroscopy, which severely interferes the reliable acquisition of the time-resolved fluorescence spectra especially for an optically dilute sample. Superfluorescence originates from the optical amplification of the vacuum quantum noise, which would be inevitably concomitant with the amplified fluorescence photons during the optical parametric amplification process. Here, we report the development of a femtosecond time-resolved fluorescence non-collinear optical parametric amplification spectrometer assisted with a 32-channel lock-in amplifier for efficient rejection of the superfluorescence background. With this spectrometer, the superfluorescence background signal can be significantly reduced to 1/300-1/100 when the seeding fluorescence is modulated. An integrated 32-bundle optical fiber is used as a linear array light receiver connected to 32 photodiodes in one-to-one mode, and the photodiodes are further coupled to a home-built 32-channel synchronous digital lock-in amplifier. As an implementation, time-resolved fluorescence spectra for rhodamine 6G dye in ethanol solution at an optically dilute concentration of 10(-5)M excited at 510 nm with an excitation intensity of 70 nJ/pulse have been successfully recorded, and the detection limit at a pump intensity of 60 μJ/pulse was determined as about 13 photons/pulse. Concentration dependent redshift starting at 30 ps after the excitation in time-resolved fluorescence spectra of this dye has also been observed, which can be attributed to the formation of the excimer at a higher concentration, while the blueshift in the earlier time within 10 ps is attributed to the solvation process.

Confirmation of direct photogeneration of intrinsic delocalized free carriers in small-molecule organic semiconductors has been a long-sought but unsolved issue, which is of fundamental significance to its application in photo-electric devices. Although the excitonic description of photoexcitation in these materials has been widely accepted, this concept is challenged by recently reported phenomena. Here we report observation of direct delocalized free carrier generation upon interband photoexcitation in highly crystalline zinc phthalocyanine films prepared by the weak epitaxy growth method using ultrafast spectroscopy. Transient absorption spectra spanning the visible to mid-infrared region revealed the existence of short-lived free electrons and holes with a diffusion length estimated to cross at least 11 molecules along the π-π stacking direction that subsequently localize to form charge transfer excitons. The interband transition was evidenced by ultraviolet-visible absorption, photoluminescence and electroluminescence spectroscopy. Our results suggest that delocalized free carriers photogeneration can also be achieved in organic semiconductors when the molecules are packed properly.

Native buckwheat, a common component of food products and medicine, has been observed to inhibit cancer cell proliferation in vitro. The aim of the present study was to evaluate the in vitro and in vivo anti-tumoral effects of recombinant buckwheat trypsin inhibitor (rBTI) on hepatic cancer cells and the mechanism of apoptosis involved. Apoptosis in the H22 cell line induced by rBTI was identified using MTT assays, DNA electrophoresis, flow cytometry, morphological observation of the nuclei, measurement of cytochrome C and assessment of caspase activation. It was identified that rBTI decreases cell viability by inducing apoptosis, as evidenced by the formation of apoptotic bodies and DNA fragmentation. rBTI-induced apoptosis occurred in association with mitochondrial dysfunction, leading to the release of cytochrome C from the mitochondria to the cytosol, as well as the activation of caspase-3, -8 and -9. In conclusion, the results of the present study suggested that rBTI specifically inhibited the growth of the H22 hepatic carcinoma cell line in vitro and in vivo in a concentration-dependent and time-dependent manner, while there were minimal effects on the 7702 normal liver cell line. In addition, rBTI‑induced apoptosis in H22 cells was, at least in part, mediated by a mitochondrial pathway via caspase-9.

This manuscript reports a new type of drug-loaded core-shell nanofibers that provide tunable biphasic release of quercetin. The nanofibers were fabricated using a modified coaxial electrospinning process, in which a polyvinyl chloride (PVC)-coated concentric spinneret was employed. Poly (vinyl pyrrolidone) (PVP) and ethyl cellulose (EC) were used as the polymer matrices to form the shell and core parts of the nanofibers, respectively. Scanning and transmission electron microscopy demonstrated that the nanofibers had linear morphologies and core-shell structures. The quercetin was found to be present in the nanofibers in the amorphous physical status, on the basis of X-ray diffraction results. In vitro release profiles showed that the PVP shell very rapidly freed its drug cargo into the solution, while the EC core provided the succedent sustained release. Variation of the drug loading permitted the release profiles to be tuned.