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The synergistic systems of photoredox and copper catalyst have already appeared as a novel formation of green synthetic chemistry, which open new avenues for chemical synthesis applications. We describe a novel strategy for the cyclization of alkyne‐tethered α‐bromocarbonyls initiated by the cleavage of C(sp3)−Br bond via the collaboration of photoredox and copper catalyst. The present protocol exhibits mildness using economical copper catalyst and visible‐light at room temperature. The gram‐scale and sunlight irradiation experiments proceeded smoothly to show the practicality of the methodology. It is notable that the newly generated oxygen in the product originates from H2O. [ABSTRACT FROM AUTHOR]

Chemodivergent tandem radical cyclization offers exciting possibilities for the synthesis of structurally diverse cyclic compounds. Herein, we revealed a chemodivergent tandem cyclization of alkene‐substituted quinazolinones under metal‐ and base‐free conditions, this transformation is initiated by alkyl radicals produced from oxidant‐induced α‐C(sp3)−H functionalization of alkyl nitriles or esters. The reaction resulted in the selective synthesis of a series of mono‐ and di‐alkylated ring‐fused quinazolinones by modulating the loading of oxidant, reaction temperature, and reaction time. Mechanistic investigations show that the mono‐alkylated ring‐fused quinazolinones is constructed by the key process of 1,2‐hydrogen shift, whereas the di‐alkylated ring‐fused quinazolinones is mainly achieved through crucial steps of resonance and proton transfer. This protocol is the first example of remote second alkylation on the aromatic ring via α‐C(sp3)−H functionalization and difunctionalization achieved by association of two unsaturated bonds in radical cyclization. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the regulation of histone-like nucleoid structuring protein (H-NS) on biofilm formation and cyclic diguanylate (c-di-GMP) synthesis in Vibrio parahaemolyticus RIMD2210633. Regulatory mechanisms were analyzed by the combined utilization of crystal violet staining, quantification of c-di-GMP, quantitative real-time polymerase chain reaction, LacZ fusion, and electrophoretic-mobility shift assay. The deletion of hns enhanced the biofilm formation and intracellular c-di-GMP levels in V. parahaemolyticus RIMD2210633. H-NS can bind the upstream promoter–proximal DNA regions of scrA, scrG, VP0117, VPA0198, VPA1176, VP0699, and VP2979 to repress their transcription. These genes encode a group of proteins with GGDEF and/or EAL domains associated with c-di-GMP metabolism. One of the mechanisms by which H-NS represses the biofilm formation by V. parahaemolyticus RIMD2210633 may be via repression of the production of intracellular c-di-GMP. [ABSTRACT FROM AUTHOR]

High-dimensional data and the small sample size problem occur in many modern pattern classification applications such as face recognition and gene expression data analysis. To deal with such data, one important step is dimensionality reduction. Principal component analysis (PCA) and between-group analysis (BGA) are two commonly used methods, and various extensions of these two methods exist. The principle of these two approaches comes from their best approximation property. From a pattern recognition perspective, we show that PCA, which is based on the total scatter matrix, preserves linear separability, and BGA, which is based on between-class scatter matrix, retains the distance between class centroids. Moreover, we propose an automatic nonparameter uncorrelated discriminant analysis (UDA) algorithm based on the maximum margin criterion (MMC). The extracted features via UDA are statistically uncorrelated. UDA combines rank-preserving dimensionality reduction and constraint discriminant analysis and also serves as an effective solution for the small-sample-size problem. Experiments with face images and gene expression data sets are conducted to evaluate UDA in terms of classification accuracy and robustness. Index Terms--Feature extraction, feature interpretability, small sample size problem, face recognition, microarray data classification.

We present theoretical and experimental studies of the infrared (IR) spectroscopy, normal Raman spectroscopy (NRS), surface-enhanced Raman spectroscopy (SERS), and surface-enhanced hyper-Raman (SEHRS) spectroscopy of trans-1,2-bis(4-pyridyl)ethylene (BPE). This centrosymmetric molecule is expected to have no common Raman and hyper-Raman lines provided that it is not strongly perturbed by adsorption on the surface. The measured SERS spectrum, obtained under electrochemical conditions on Ag film over nanosphere (AgFON) electrodes, shows a well defined C=C stretch band that is not seen in the SEHRS spectrum, but many of the other bands overlap closely. We use ab initio calculations for isolated BPE to assign the spectra, and find excellent agreement between the calculated and measured IR and SERS spectra, and good agreement between the calculated and measured SEHRS spectrum. We find that the apparently overlapping IR, SERS, and SEHRS bands are in fact due to modes that have similar vibrational characteristics but different symmetry. Our results indicate that SEHRS spectra are consistent with the expected (three photon) selection rules and intensities. This rules out an alternative mechanism in which the observed spectrum arises from surface second harmonic generation (SHG) followed by SERS excited at the second harmonic frequency. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present a discrete dipole approximation (DDA) method to determine extinction and Raman intensities for small metal particles of arbitrary shape. The Raman intensity calculation involves evaluation of surface electromagnetic fields, and thus is relevant to surface enhanced Raman scattering (SERS) intensities. We demonstrate convergence of the method by considering light absorption and scattering from an isolated spheroid, from an isolated tetrahedron, from two coupled spheroids, and from a spheroid on a flat surface. We also examine comparisons with traditional T-matrix methods. Extensions and simplifications of the method in studies of clusters and arrays of particles are presented. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Ab initio and semiempirical molecular orbital methods have been used to calculate the bulk and surface Raman and hyperRaman spectra of pyridine. Similar calculations for benzene are also reported. For both molecules, we compare the results with available bulk and surface experiments. In all calculations, the polarizability and hyperpolarizability derivatives are evaluated using normal coordinates that are obtained from Hartree–Fock (HF) calculations. The Raman results are somewhat sensitive to the basis set used in determining the normal coordinates, and the hyper-Raman spectra are strongly sensitive. The Raman and hyper-Raman spectra have been calculated at zero frequency using HF methods (GAUSSIAN 90), and finite frequency using INDO (intermediate neglect of differential overlap) methods (zindo). The frequency dependence of the results is found to be minor. Comparisons with experiment indicate that the inclusion of diffuse basis functions is crucial to the accuracy of the HF calculations. For such basis sets, the benzene Raman and hyper-Raman spectra provided by HF are in excellent agreement with experiment. Raman spectra from HF for pyridine also agree well, but hyper-Raman spectra agree only in part. Changes in Raman and hyper-Raman spectra calculated in going from bulk to surface generally agree with observations. The corresponding bulk and surface spectra from zindo are usually less accurate, especially the hyper-Raman spectra, and especially the out of plane modes. Estimates of the surface hyper-Raman enhancement factor are in the range 1011–1012 for pyridine on silver electrodes. [ABSTRACT FROM AUTHOR]

Brownmillerite-type oxides BaInMnAlO (0 ≤ x ≤ 0.6, 0 ≤ y ≤ 0.5) were prepared at 1300°C through solid-state reaction. X-ray diffraction (XRD) analysis showed that the structure symmetry evolved from orthorhombic to cubic with increasing Mn and Al contents. When y was greater than 0.3, peaks associated with small amounts of BaAlO and BaInAlO impurities were observed in the XRD patterns. When substituted with a small amount of Mn ( x ≤ 0.3), the BaInMnAlO samples exhibited an intense turquoise color. The color changed to green and dark-green with increasing Mn concentration. UV-vis absorbance spectra revealed that the color changed only slightly upon Al doping. The valence state of Mn ions in BaInMnAlO was confirmed to be +5 on the basis of X-ray photoelectron spectroscopic analysis. According to this analysis, the intense turquoise color of the BaInMnAlO samples is rooted in the existence of Mn; thus, the introduction of Al does not affect the optical properties of the compounds. [ABSTRACT FROM AUTHOR]

Background: Lytic mycobacteriophage D29 has the potential for tuberculosis treatment including multidrug-resistant strains. The aims of this study are to investigate deposition and distribution of aerosolized phage D29 particles in naive Balb/C mice, together with pharmacokinetics and evaluation of acute lung injury. Methods: Pharmacokinetics and BALF (bronchoalveolar lavage fluids) were analyzed after administration of phage D29 aerosols by endotracheal route using Penn-century aerosolizer; Collison 6-jet and Spinning top aerosol nebulizers (STAG) were used to generate phage aerosols with different particle size distributions in nose-only inhalation experiments. After exposure, deposited amounts of phage D29 particles in respiratory tracts were measured, and deposition efficiencies were calculated. A typical path deposition model for mice was developed, and then comparisons were made between predictions and experimentally measured results. Results: Approximately 10% of aerosolized phages D29 reached lung of mouse for pulmonary delivery, and were completely eliminated until 72 h after administration. In contrast, about 0.1% of intraperitoneal injected phages reached the lung, and were almost eliminated at 12 h time point. The inflammation was hardly observed in lung according to the results of BALF analysis. The CMADs (count median aerodynamic diameters) of generated aerosol by Collison and STAG nebulizer were 0.8 μm and 1.5 μm, respectively. After nose-only exposure, measured deposition efficiencies in whole respiratory tract for 0.8 and 1.5 μm phage particles were below 1% and 10%, respectively. Predictions of the computer deposition model compared fairly well with experimentally measured results. Conclusions: This is the first systematic study of phage D29 aerosol respiratory challenge in laboratory animals. It provides evidence that aerosol delivery of phage D29 is an effective way for treating pulmonary infections caused by Mycobacterium tuberculosis. This research will also provide important data for future inhalation experiments. [ABSTRACT FROM AUTHOR]

This paper introduces a design methodology for a multi-tesla permanent magnet. Normally the permanent magnet is designed to provide the magnetic fields below 2 T. By employing high performance materials and the 3D magnetic circuit design method, a prototype magnet has been built and generates maximum 2.987 T field strength in 0.008 m air gap with less than 20 kg total weight. It is expected a practical, compact and light-weight high field source for NMR, MRI or other instruments. [ABSTRACT FROM PUBLISHER]

A design example of an asymmetric transverse gradient coil by a numerical approach is presented in this paper. The gradient coil is designed for brain imaging by ultra-high field MRI. The coil can achieve high gradient strength and high slew rate due to its small diameter. The wire pattern of the coil is asymmetric with the diameter spherical volume (DSV) located close to the edge of the coil, which enables the head of the subject to reach the DSV. A corresponding shield coil is also designed to suppress the induced eddy currents in surrounding structures. [ABSTRACT FROM PUBLISHER]

Extracting biologically relevant information from DNA microarrays is a very important task for drug development and test, function annotation, and cancer diagnosis. Various clustering methods have been proposed for the analysis of gene expression data, but when analyzing the large and heterogeneous collections of gene expression data, conventional clustering algorithms often cannot produce a satisfactory solution. Biclustering algorithm has been presented as an alternative approach to standard clustering techniques to identify local structures from gene expression data set. These patterns may provide clues about the main biological processes associated with different physiological states. In this paper, different from existing bicluster patterns, we first introduce a more general pattern: correlated bicluster, which has intuitive biological interpretation. Then, we propose a novel transform technique based on singular value decomposition so that identifying correlated-bicluster problem from gene expression matrix is transformed into two global clustering problems. The Mixed-Clustering algorithm and the Lift algorithm are devised to efficiently produce \delta-corBiclusters. The biclusters obtained using our method from gene expression data sets of multiple human organs and the yeast Saccharomyces cerevisiae demonstrate clear biological meanings. [ABSTRACT FROM PUBLISHER]

Abstract: Luteolin (3′,4′,5,7-tetrahydroxyflavone) is an active constituent of Lonicera japonica (Caprifoliaceae), and has been reported to produce anti-tumor activities. However, the apoptosis-inducing activity of luteolin still remains unknown. Flavonoids have been found to posses prooxidant and antioxidant action. The biological and pharmacological effect of flavonoid may depend upon its behavior as either an antioxidant or a prooxidant. Our experiments found that luteolin-induced CH27 cell apoptosis was accompanied by activation of antioxidant enzymes, such as superoxide dismutase and catalase, but not through the production of reactive oxygen species and disruption of mitochondrial membrane potential. Therefore, the effects of luteolin on CH27 cell apoptosis were suspected to result from the antioxidant rather than the prooxidant action of luteolin. [Copyright &y& Elsevier]

The synergistic systems of photoredox and copper catalyst have already appeared as a novel formation of green synthetic chemistry, which open new avenues for chemical synthesis applications. We describe a novel strategy for the cyclization of alkyne-tethered α-bromocarbonyls initiated by the cleavage of C(sp 3 )-Br bond via the collaboration of photoredox and copper catalyst. The present protocol exhibits mildness using economical copper catalyst and visible-light at room temperature. The gram-scale and sunlight irradiation experiments proceeded smoothly to show the practicality of the methodology. It is notable that the newly generated oxygen in the product originates from H 2 O., (© 2023 Wiley-VCH GmbH.)

Chemodivergent tandem radical cyclization offers exciting possibilities for the synthesis of structurally diverse cyclic compounds. Herein, we revealed a chemodivergent tandem cyclization of alkene-substituted quinazolinones under metal- and base-free conditions, this transformation is initiated by alkyl radicals produced from oxidant-induced α-C(sp 3 )-H functionalization of alkyl nitriles or esters. The reaction resulted in the selective synthesis of a series of mono- and di-alkylated ring-fused quinazolinones by modulating the loading of oxidant, reaction temperature, and reaction time. Mechanistic investigations show that the mono-alkylated ring-fused quinazolinones is constructed by the key process of 1,2-hydrogen shift, whereas the di-alkylated ring-fused quinazolinones is mainly achieved through crucial steps of resonance and proton transfer. This protocol is the first example of remote second alkylation on the aromatic ring via α-C(sp 3 )-H functionalization and difunctionalization achieved by association of two unsaturated bonds in radical cyclization., (© 2023 Wiley-VCH Verlag GmbH.)

Targeted therapy has been standardized in front-line therapies for metastatic colorectal cancer (mCRC), while explicit recommendations for third- or later-line are still lacking. This study evaluated the efficacy and safety of combining targeted therapy with chemotherapy in the third- or later-line treatment for mCRC via meta-analysis, providing evidence-based guidance for clinical or research practice. Comprehensive retrieval of related studies was conducted according to the PRISMA guideline. Studies were stratified with patient characteristics and pharmacological classification of the drugs. For the data available for quantitative analysis, pooled overall response rate, disease control rate, hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS), and adverse events rate with respective 95% confidence intervals (CIs) were calculated. A total of 22 studies (1,866 patients) were included in this meta-analysis. Data from 17 studies (1,769 patients) involving targets of epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) were extracted for meta-analyses. The overall response rates for monotherapy and combined therapy were 4% (95% CI: 3%, 5%) and 20% (95% CI: 11%, 29%). The pooled HRs (combined therapy vs. mono) for OS and PFS were 0.72 (95% CI: 0.53, 0.99) and 0.34 (95% CI: 0.26, 0.45). Another five studies were included in narrative depiction, involving targets of BRAF, HER-2, ROS1, and NTRK. The findings of this meta-analysis indicate that VEGF and EGFR inhibitors manifest promising clinical response rates and prolonged survival in the treatment of mCRC with acceptable adverse events., 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 © 2023 Xue, Li, Ding, Wu, Pei, Ma, Xie and Yang.)

The diagnosis of lung cancer has long been a problem facing clinicians worldwide, and the emergence of electromagnetic navigation bronchoscopy (ENB) has played a critical role in the early diagnosis of lung cancer. Compared with other types of biopsy techniques (e.g., transthoracic needle biopsy, bronchoscopy, thoracoscopic biopsy, and thoracotomy), ENB guarantees high diagnostic accuracy and safety. In recent years, with the continuous development of ENB technology, the scope of its epitaxy has also expanded. This technology is no longer a simple auxiliary diagnosis test but an innovative technology that simultaneously assists in surgical treatment, opening new avenues of research for the treatment of early-stage lung cancer. However, ENB, as a human-mediated operating system, has some limitations and uncertainties in its actual clinical application and promotion, which need to be addressed as we continue to develop ENB technology. In response to the bottleneck in developing ENB technology in current clinical diagnosis and treatment, relevant scientific research and development personnel and clinicians have also performed continuing exploration and improvement of methods. However, to completely overcome the limitations of ENB, more technological innovations are needed. In this review, we describe the current major clinical application directions, application advantages, and limitations of ENB., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/tcr-20-3020). The authors have no conflicts of interest to declare., (2021 Translational Cancer Research. All rights reserved.)