This research reported a hydrogel loaded with the ethanolic and methanolic extracts of Eupatorium glutinosum Lam. The E. glutinosum extracts were characterized by phytochemical screening, ...Fourier-transform infrared spectroscopy (FTIR), thin-layer chromatography (TLC), and UV/Vis profile identification. This research also evaluated the pharmacological activity of the extracts using antimicrobial, antioxidant, and anti-inflammatory assays prior to polymeric encapsulation. Results indicate that extracts inhibit the Escherichia colii DH5-α (Gram negative) growth; excellent antioxidant activity was evaluated by the ferric reducing power and total antioxidant activity assays, and extracts showed an anti-hemolytic effect. Moreover, the cotton and microcrystalline cellulose hydrogels demonstrate successful encapsulation based on characterization and kinetics studies such as FTIR, extract release, and swelling degree. Moreover, effective antibacterial activity was registered by the loaded hydrogel. The overall results encourage and show that Eupatorium glutinosum-loaded hydrogel may find a wide range of bandage and wound healing applications in the biomedical area.
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•A hydrogen bond regulates dynamics of the O intermediate state of heliorhodopsin.•SNap bond is the key hydrogen bond between transmembrane helices 3 and 4.•A distorted α helix is ...involved in light-induced conformation changes in heliorhodopsin.•SNap bond exists ubiquitously in heliorhodopsins found in the genome database.
Heliorhodopsin (HeR) is a new rhodopsin family discovered in 2018 through functional metagenomic analysis. Similar to microbial rhodopsins, HeR has an all-trans retinal chromophore, and its photoisomerization to the 13-cis form triggers a relatively slow photocycle with sequential intermediate states (K, M, and O intermediates). The O intermediate has a relatively long lifetime and is a putative active state for transferring signals or regulating enzymatic reactions. Although the first discovered HeR, 48C12, was found in bacteria and the second HeR (TaHeR) was found in archaea, their key amino acid residues and molecular architectures have been recognized to be well conserved. Nevertheless, the rise and decay kinetics of the O intermediate are faster in 48C12 than in TaHeR. Here, using a new infrared spectroscopic technique with quantum cascade lasers, we clarified that the hydrogen bond between transmembrane helices (TM) 3 and 4 is essential for the altered O kinetics (Ser112 and Asn138 in 48C12). Interconverting mutants of 48C12 and TaHeR clearly revealed that the hydrogen bond is important for regulating the dynamics of the O intermediate. Overall, our study sheds light on the importance of the hydrogen bond between TM3 and TM4 in heliorhodopsins, similar to the DC gate in channelrhodopsins.
Australian Geological Surveys are the custodians of a major national asset in the form of historically drilled and archived drill cores of the top few kilometres of the continent acquired by ...government agencies and companies over many decades. The AuScope National Virtual Core Library (NVCL) component of the AuScope Earth Model comprises geological/rock samples, technology, people and database/delivery infrastructure located in six nationally distributed nodes and is aimed at extracting additional value from this asset. The technology components of the NVCL comprise an integrated suite of hardware (HyLogger-3) and software (TSG-Core) systems for the imaging and hyperspectral characterisation of drill cores in their original core trays and the interpretation of their contained oxide, carbonate, hydrous and anhydrous silicate mineralogy. The HyLogger-3 includes state-of-the-art Fourier Transform Spectrometers that continuously measure calibrated spectral reflectance from nominal 10 by 18 mm fields of view. These spectra are in turn passed through a series of automatic and semi-automatic pre-processing and mineralogical unmixing algorithms. These, along with numerous other tools in TSG-Core, output a variety of mineralogical and image products for use by scientists in many branches of the earth sciences. This paper provides a functional overview of the HyLogging hardware and software tools available in each of Australia's Geological Surveys.
The application of newly synthesized CA/ZrO.sub.2 nanocomposite as a sorbent for the effective removal of As(III), As(V), and ROX contaminants from aqueous solution has been investigated. The ...synthesized nanocomposite was analyzed by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis, Fourier transform infrared spectroscopy (FTIR), Brunauer-Emmett-Teller (BET) analysis, and X-ray diffractometer (XRD) to determine its applicability for the contaminant's removal. SEM images show the particles are unevenly decorated, with an average particle size of 100 nm. BET analysis reveals that the synthesized CA/ZrO.sub.2 has a specific surface area of 208.64 m.sup.2/g. The adsorption capacity of CA/ZrO.sub.2 was evaluated in batch mode for pollutants such as As(III), As(V), and ROX based on variation in pH, metal ion concentration, and contact time, respectively. The maximum removal efficiency was found to be 89% for As(III), 95.3% for As(V), and 97% for ROX. Similarly, equilibrium data fits well with Langmuir model having maximum monolayer adsorption capacity of 180, 129, and 118 mg/g, respectively. Based on kinetic studies, pseudo-second-order model finds highest suitability with the process. Thermodynamic studies reveal the endothermic nature of adsorption process. The prepared CA/ZrO.sub.2 showed good regenerative capacity (four cycles), making it a suitable adsorbent for arsenic contaminant removal. Graphical
Polymer identification of plastic marine debris can help identify its sources, degradation, and fate. We optimized and validated a fast, simple, and accessible technique, attenuated total reflectance ...Fourier transform infrared spectroscopy (ATR FT-IR), to identify polymers contained in plastic ingested by sea turtles. Spectra of consumer good items with known resin identification codes #1–6 and several #7 plastics were compared to standard and raw manufactured polymers. High temperature size exclusion chromatography measurements confirmed ATR FT-IR could differentiate these polymers. High-density (HDPE) and low-density polyethylene (LDPE) discrimination is challenging but a clear step-by-step guide is provided that identified 78% of ingested PE samples. The optimal cleaning methods consisted of wiping ingested pieces with water or cutting. Of 828 ingested plastics pieces from 50 Pacific sea turtles, 96% were identified by ATR FT-IR as HDPE, LDPE, unknown PE, polypropylene (PP), PE and PP mixtures, polystyrene, polyvinyl chloride, and nylon.
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•We validate ATR FT-IR to identify polymers of weathered and ingested plastics.•We outline criteria to differentiate HDPE from LDPE samples.•Cutting or cleaning ingested plastics with water improves identification.•A database of standards is not required for polymer identification.•Collaborations of life and materials sciences address plastic debris issues.
We present deep near-infrared spectroscopy of six quasars at 6.1 ≤ z ≤ 6.7 with Very Large Telescope/X-Shooter and Gemini-N/GNIRS. Our objects, originally discovered through a wide-field optical ...survey with the Hyper Suprime-Cam (HSC) Subaru Strategic Program (HSC-SSP), have the lowest luminosities (−25.5 mag ≤ M1450 ≤ −23.1 mag) of the z > 5.8 quasars with measured black hole (BH) masses. From single-epoch mass measurements based on Mg ii λ2798, we find a wide range in BH masses, from MBH = 107.6 to 109.3 M . The Eddington ratios Lbol/LEdd range from 0.16 to 1.1, but the majority of the HSC quasars are powered by MBH ∼ 109 M supermassive black holes (SMBHs) accreting at sub-Eddington rates. The Eddington ratio distribution of the HSC quasars is inclined to lower accretion rates than those of Willott et al., who measured the BH masses for similarly faint z ∼ 6 quasars. This suggests that the global Eddington ratio distribution is wider than has previously been thought. The presence of MBH ∼ 109 M SMBHs at z ∼ 6 cannot be explained with constant sub-Eddington accretion from stellar remnant seed BHs. Therefore, we may be witnessing the first buildup of the most massive BHs in the first billion years of the universe, the accretion activity of which is transforming from active growth to a quiescent phase. Measurements of a larger complete sample of z 6 low-luminosity quasars, as well as deeper observations with future facilities, will enable us to better understand the early SMBH growth in the reionization epoch.
Total volatile basic nitrogen (TVB-N) and total viable count (TVC) are two important indicators for evaluating and controlling the quality and safety of chicken fillets. The aim of this study is to ...evaluate two hyperspectral imaging techniques (visible near-infrared (Vis-NIR) and NIR) in combination with low-level and intermediate-level fusion strategies (LLF and ILF) for the prediction of multiple quality indicators of chicken fillets stored at 4 °C. Quantitative predictions using partial least squares regression (PLSR) were established after preprocessing and feature wavelength selection. The results showed that the data fusion strategy exhibited better performance in both indicators compared to individual data. The LLF strategy showed optimal performance in predicting the TVC content with an RP2 of 0.9275 and an RMSEP of 0.1889, while the ILF strategy was best in predicting the TVB-N content with an RP2 of 0.8652 and an RMSEP of 2.6094. Moreover, the optimal models based on selected bands were used to achieve visual maps of the TVB-N and TVC contents. Although validation with an independent batch of samples was not used, it was a feasibility and valuable study. The experiment results demonstrated that the fusion of two types of hyperspectral data can be successfully used to evaluation of chicken multiple qualities, and provided a potential method for monitoring and detection of meat qualities.
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•Two types of HSI techniques were used and combined to predict TVB-N and TVC.•Preprocessing and feature extraction algorithms were employed to seek the optimal combination.•The superiority of low- and intermediate-level fusion strategies was demonstrated.•Distribution maps were visualized to observe the changes of chicken qualities.
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•NIR and MIR spectroscopy were used for origin identification and quality evaluation.•High-level data fusion strategies were used to integrate NIR and MIR spectral data.•The data ...fusion model provided the best model for origin identification of LJF.•A data fusion model was developed to convert NIR and MIR spectra to HPLC data.•The performance and feasibility of the conversion was investigated.
A data fusion strategy based on near-infrared (NIR) and mid-infrared (MIR) spectroscopy techniques were developed for rapid origin identification and quality evaluation of Lonicerae japonicae flos (LJF). A high-level data fusion for origin identification was formed using the soft voting method. This data fusion model achieved accuracy, log-loss value and Kappa value of 95.5%, 0.347 and 0.910 on the prediction set. The spectral data were converted to liquid chromatography data using a data fusion model constructed by the weighted average algorithm. The Euclidean distance and adjusted cosine similarity were used to evaluate the similarity between the converted and the real chromatographic data, with results of 247.990 and 0.996, respectively. The data fusion models all performed better than the models constructed using single data. This indicates that multispectral data fusion techniques have a wide range of application prospects and practical value in the quality control of natural products such as LJF.
Monomers of meta-fluorophenol (mFP) were trapped from the gas phase into cryogenic argon and nitrogen matrices. The estimated relative energies of the two conformers are very close, and in the gas ...phase they have nearly equal populations. Due to the similarity of their structures (they only differ in the orientation of the OH group), the two conformers have also similar predicted vibrational signatures, which makes the vibrational characterization of the individual rotamers challenging. In the present work, it has been established that in an argon matrix only the most stable trans conformer of mFP exists (the OH group pointing away from the fluorine atom). On the other hand, the IR spectrum of mFP in a nitrogen matrix testifies to the simultaneous presence in this matrix of both the trans conformer and of the higher-energy cis conformer (the OH group pointing toward the fluorine atom), which is stabilized by interaction with the matrix gas host. We found that the exposition of the cryogenic Nsub.2 matrix to the Globar source of the infrared spectrometer affects the conformational populations. By collecting experimental spectra, either in the full mid-infrared range or only in the range below 2200 cmsup.−1, we were able to reliably distinguish two sets of experimental bands originating from individual conformers. A comparison of the two sets of experimental bands with computed infrared spectra of the conformers allowed, for the first time, the unequivocal vibrational identification of each of them. The joint implementation of computational vibrational spectroscopy and matrix-isolation infrared spectroscopy proved to be a very accurate method of structural analysis. Some mechanistic insights into conformational isomerism (the quantum tunneling of hydrogen atom and vibrationally-induced conformational transformations) have been addressed. Finally, we also subjected matrix-isolated mFP to irradiations with UV light, and the phototransformations observed in these experiments are also described.
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