Interrogation of 3d Transition Bimetallic Nanocrystal Nucleation and Growth Using In Situ Electron Microscope and Synchrotron X-ray Techniques.

Understanding the nucleation and growth mechanism of 3d transition bimetallic nanocrystals (NCs) is crucial to developing NCs with tailored nanostructures and properties. However, it remains a significant challenge due to the complexity of 3d bimetallic NCs formation and their sensitivity to oxygen. Here, by combining in situ electron microscopy and synchrotron X-ray techniques, we elucidate the nucleation and growth pathways of Fe-Ni NCs. Interestingly, the formation of Fe-Ni NCs emerges from the assimilation of Fe into Ni clusters together with the reduction of Fe-Ni oxides. Subsequently, these NCs undergo solid-state phase transitions, resulting in two distinct solid solutions, ultimately dominated by γ-Fe3Ni2. Furthermore, we deconvolve the interplays between local coordination and electronic state concerning the growth temperature. We directly visualize the oxidation-state distributions of Fe and Ni at the nanoscale and investigate their changes. This work may reshape and enhance the understanding of nucleation and growth in atomic crystallization.

3 kW forward-pumped fiber laser via pump recycler.

We report a single-end forward-pumped fiber laser with a record high output power of 3 kW. The laser is assembled exclusively from commercially widespread components such as the Yb-doped fiber with core/cladding diameter of 20/400 µm, pump laser diodes at an emission wavelength of 915 nm, and a signal and pump fiber combiner that serves as the pump recycler. The record high power arises from the combination of the 915 nm pumping and pump recycler with an effective reflectivity of 78%, increasing simultaneously the thresholds for stimulated Raman scattering and transverse mode instability (TMI). The length of the oscillator was also varied experimentally from 20 m to 5 m, showing a contrast of up to 19% in the TMI threshold. This shows the importance of accurately partitioning the Yb-doped fiber length in between the oscillator and amplifier sections to minimize the impact of TMI.

Effective all-fiber pump recycler for kilowatt fiber lasers.

We report an effective pump recycler for industrial kilowatt fiber lasers. The pump recycler is a (6+1)×1 tapered fiber bundle, with signal ports of Ge-doped fiber (GDF) with core/cladding diameters of 20/400 µm and pump fiber ports (PFPs) with core/cladding diameters of 135/155 µm. By splicing PFPs in pairs, 77.9% of the residual pump light reaching the pump recycler is sent back to the cladding of the GDF. The insertion of a pump recycler increases the power conversion efficiency (PCE) of a fiber laser using an Yb-doped fiber (YDF) from 61.0% to 70.5%, with a maximum output power of 2.78 kW. The laser with a 20 m long YDF and pump recycler compares well to another laser using a 40 m long YDF without pump recycler. In both cases, the PCE is comparable but the laser with a 20 m long YDF and pump recycler benefits from reduced stimulated Raman scattering (SRS), thus enabling an 80% increase in Raman threshold. By giving access to short YDF length, the tapered fiber bundle represents an effective pump recycler since it enables reducing SRS while keeping a large PCE.

Raman suppression within the gain fiber of high-power fiber lasers.

We report the effective suppression of Raman emission in a monolithic ytterbium-doped fiber laser by the insertion of a chirped and tilted fiber Bragg grating (CTFBG) directly within the gain fiber of the laser. In comparison with a non-compensated filtered laser cavity for which the Raman threshold occurs at an output power of 1.54 kW, the insertion of a CTFBG within the gain medium leads to an increase in the Raman threshold by 260 W. We also demonstrate that the insertion of a CTFBG in between a laser cavity and a passive beam delivery fiber leads to an increase in the Raman threshold by 100 W with respect to the non-compensated case.

Bimetallic nanoalloys planted on super-hydrophilic carbon nanocages featuring tip-intensified hydrogen evolution electrocatalysis.

The insufficient availability and activity of interfacial water remain a major challenge for alkaline hydrogen evolution reaction (HER). Here, we propose an "on-site disruption and near-site compensation" strategy to reform the interfacial water hydrogen bonding network via deliberate cation penetration and catalyst support engineering. This concept is validated using tip-like bimetallic RuNi nanoalloys planted on super-hydrophilic and high-curvature carbon nanocages (RuNi/NC). Theoretical simulations suggest that tip-induced localized concentration of hydrated K+ facilitates optimization of interfacial water dynamics and intermediate adsorption. In situ synchrotron X-ray spectroscopy endorses an H* spillover-bridged Volmer‒Tafel mechanism synergistically relayed between Ru and Ni. Consequently, RuNi/NC exhibits low overpotential of 12 mV and high durability of 1600 h at 10 mA cm‒2 for alkaline HER, and demonstrates high performance in both water electrolysis and chlor-alkali electrolysis. This strategy offers a microscopic perspective on catalyst design for manipulation of the local interfacial water structure toward enhanced HER kinetics.

A turn on fluorescent assay for γ-glutamyltransferase activity and its application in biological imaging.

γ-glutamyltransferase (GGT) is widely presented in living cells and overexpressed in many tumor tissues. Therefore, it is generally considered as an important biomarker for the detection of tumor, especially for liver cancer. Accurate determination of its activity is helpful for early diagnosis and treatment of related diseases. In this work, a "turn on" fluorescent probe NSA-GGT for the detection of GGT activity based on glutamine bond was designed and synthesized by employing dansylamino as fluorophore. The probe shows good water solubility and can be well dispersed in aqueous buffer. After incubated with GGT in phosphate buffer, the fluorescence of NSA-GGT centered at ∼523 nm increased over 25-fold. This sensing pattern exhibits an intriguing sensing sensitivity for GGT, and has good performance on intracellular GGT staining, serving as a promising candidate for GGT measurement. Subsequent biological experiments showed that probe NSA-GGT could also be used for fluorescent imaging of GGT activity in living cells and animal tissues.

Statistical analysis of age-related skin parameters.

BACKGROUND: Due to the increasing interest in human anti-aging, demand for a higher quality of life, and technological advancement, the development of anti-aging skincare has great market prospects. Most cosmetic companies develop products driven by the market or focus on the mechanism of action of substances and the behavior of skin; however, little research utilizes skin parameters and large data methodology to develop skincare products. OBJECTIVE: To instruct consumers to purchase skincare products and to guide skincare research toward the development of customer-targeted products. METHODS: A total of 815 Chinese subjects (83 male; 732 female) from five different cities were included. We measured 14 indices in each subject, including moisture, transepidermal water loss (TEWL), and sebum levels. We performed multiple regression analysis to understand the relationship between skin indices and aging; a novel approach is shown using the R software. RESULTS: The exact age at which changes in each skin index occurred could be demonstrated by this method of analysis: 39, 38, 48, 46, and 56 years old with respect to the L value, Melanin, Rt, Rm, and Rz, respectively. CONCLUSION: With the use of statistical analysis, consumers can be more efficiently targeted and choose suitable products considering particular skin parameter changing points; thus, skincare companies will not only meet customer requirements but also better control budgets.

GABRA3 promotes lymphatic metastasis in lung adenocarcinoma by mediating upregulation of matrix metalloproteinases.

Tumor metastasis is the main reason for the poor prognosis of lung cancer patients. The GABAA receptor subunit GABRA3 is reportedly upregulated in lung cancer. Herein, we show that high GABRA3 protein expression in lung adenocarcinoma correlated positively with disease stage, lymphatic metastasis status and poor patient survival. In addition, GABRA3 induced MMP-2 and MMP-9 expression through activation of the JNK/AP-1 signaling pathway, which enhanced lymphatic metastasis by lung adenocarcinoma both in vitro and in vivo. These results indicate that GABRA3 promotes lymph node metastasis and may thus be an effective therapeutic target for anticancer treatment.

Frequent alterations in cytoskeleton remodelling genes in primary and metastatic lung adenocarcinomas.

The landscape of genetic alterations in lung adenocarcinoma derived from Asian patients is largely uncharacterized. Here we present an integrated genomic and transcriptomic analysis of 335 primary lung adenocarcinomas and 35 corresponding lymph node metastases from Chinese patients. Altogether 13 significantly mutated genes are identified, including the most commonly mutated gene TP53 and novel mutation targets such as RHPN2, GLI3 and MRC2. TP53 mutations are furthermore significantly enriched in tumours from patients harbouring metastases. Genes regulating cytoskeleton remodelling processes are also frequently altered, especially in metastatic samples, of which the high expression level of IQGAP3 is identified as a marker for poor prognosis. Our study represents the first large-scale sequencing effort on lung adenocarcinoma in Asian patients and provides a comprehensive mutational landscape for both primary and metastatic tumours. This may thus form a basis for personalized medical care and shed light on the molecular pathogenesis of metastatic lung adenocarcinoma.

MicroRNA-26a/b regulate DNA replication licensing, tumorigenesis, and prognosis by targeting CDC6 in lung cancer.

UNLABELLED: Cancer is characterized by mutations, genome rearrangements, epigenetic changes, and altered gene expression that enhance cell proliferation, invasion, and metastasis. To accommodate deregulated cellular proliferation, many DNA replication-initiation proteins are overexpressed in human cancers. However, the mechanism that represses the expression of these proteins in normal cells and the cellular changes that result in their overexpression are largely unknown. One possible mechanism is through miRNA expression differences. Here, it is demonstrated that miR26a and miR26b inhibit replication licensing and the proliferation, migration, and invasion of lung cancer cells by targeting CDC6. Importantly, miR26a/b expression is significantly decreased in human lung cancer tissue specimens compared with the paired adjacent normal tissues, and miR26a/b downregulation and the consequential upregulation of CDC6 are associated with poorer prognosis of patients with lung cancer. These results indicate that miR26a/b repress replication licensing and tumorigenesis by targeting CDC6. IMPLICATIONS: The current study suggests that miR26a, miR26b, and CDC6 and factors regulating their expression represent potential cancer diagnostic and prognostic markers as well as anticancer targets.

[Determination of 11 ultraviolet absorbents in sun-screening cosmetics by liquid chromatography-tandem mass spectrometry].

A method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been established for the simultaneous determination of eleven ultraviolet absorbents in sunscreening cosmetics. The cosmetic sample was extracted by methanol-ethanol-water (80: 10: 10, v/v/v). The extract was separated by reversed-phase high performance liquid chromatography on an Eclipse XDB-C18 chromatographic column (150 mm x 4.6 mm, 5 microm) with a gradient elution of acetonitrile and water containing 0.1% formic acid. The analyte was detected by MS/ MS with the multiple reaction monitoring (MRM) mode. The qualitative analysis was based on the retention time and the relative abundance ratio of the characteristic ions, and quantitative analysis on calibration curve method. The research results showed that the limits of quantification (LOQ, S/N = 10) of the eleven ultraviolet absorbents ranged from 200 to 500 mg/kg and the average recoveries ranged from 77. 17% to 98.32% with the relative standard deviations from 2.40% to 11.11%. The method is suitable to detect the eleven ultraviolet absorbents in cream and milky sun-screening cosmetics.

[Simultaneous determination of 6 forbidden colorants in cosmetics by high performance liquid chromatography-tandem mass spectrometry].

A method of high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has been established for the simultaneous determination of six forbidden colorants including Sudan IV, Acid Violet 49, Sudan Blue 2, Solvent Red 49, Basic Violet 1 and Pigment Orange 5 in cream and powdery matrix cosmetics. The samples were extracted with ethanol-acetonitrile (3:2, v/v) solution by ultrasonic technique for 20 min, then centrifuged for purification and enriched by nitrogen blowing sequentially. The analytes were isolated on a Luna C18 column (150 mm x 2.1 mm, 5 microm) by gradient elution with methanol and 10 mmol/L ammonium acetate as the mobile phases, and detected by MS/MS in the multiple reaction monitoring (MRM) mode. The qualitative analysis was based on the retention time and the relative abundance ratio of the characteristic ions, and the quantitative analysis on calibration curve method. The results showed that the limits of quantification (LOQ, S/N= 10) of the six colorants ranged from 0.1 to 10 microg/kg and the average recoveries were from 86.67% to 98.22% with the relative standard deviations (RSDs) from 4.01% to 7.01%. The method is simple and rapid with high sensitivity and good reproducibility, and suitable for the determination of the six forbidden colorants in cosmetics.

[Determination of hormone multi-residues in animal tissues by gas chromatography-mass spectrometry].

A method of gas chromatography-mass spectrometry (GC-MS) for the simultaneous determination of nine sex hormone residues, such as hexestrol, diethylstilbestrol, dienestrol, etiocholan-3alpha-ol-17-one, epitestosterone, estrone, estradiol, ethinylestradiol and estriol, in animal tissues was developed. The sex hormones were extracted with acetonitrile, then cleaned-up with a C18 solid-phase extraction (SPE) column. The microwave-assisted derivatization of the target components with N,O-bis( trimethylsilyl) trifluoroacetamide (BSTFA) and trimethylchlorosilane (TMCS) (99:1, v/v) using pyridine as solvent was performed, and then the derivatives were analyzed by GC-MS. The limits of detection were 0.1-1 microg/kg for all hormones, and the limits of quantification were 0.2-2 microg/kg. The average recoveries of sex hormones were 68.8%-93.1%. The relative standard deviations (RSDs) of inter- and intra-assay were 4.1%-22.3% and 3.1%-17.9%, respectively. The real sample tests showed this method can be used for the sensitive and accurate determination of multi-sex hormones residues in biological samples.