bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rooibos agro‐processing waste as herbal tea products: optimisation of soluble solids extraction from dust and application to improve sensory profile, colour and flavonoid content of stem infusions
Authors: Sishi Manzimase , Muller Magdalena , de Beer Dalene , van der Rijst Marieta , Joubert Elizabeth 
Published: January 2019

AbstractBACKGROUNDRooibos represents 10% of the global herbal tea market. Shrinking production areas as a result of climate change necessitate the maximum conversion of plant biomass to product. The present study aimed to determine the potential of rooibos tea processing waste (i.e. fine dust and coarse stems) as potential flavour and herbal tea ingredients, respectively.RESULTSHot water extraction of soluble solids (SS) from rooibos dust was optimised and extracts from different production batches (n = 20) were prepared. Their sensory profiles were similar, although less intense than that of infusions of commercial rooibos (n = 20) when diluted to the same SS content. The turbidity and flavonoid content of the diluted extracts was mostly lower (P < 0.05) than that of commercial rooibos. An atypical and negative aroma attribute, ‘planky/pencil shavings’, was predominant in the stem infusions (n = 20), which contained less SS (P < 0.05) than commercial rooibos. Blends of stem infusion and extract could not effectively mask this negative aroma note (P > 0.05).CONCLUSIONRooibos dust could be used to produce a rooibos flavour extract, whereas the prominent atypical, negative ‘planky/pencil shavings’ aroma note of the stems would limit their inclusion in commercial rooibos blends. © 2019 Society of Chemical Industry
Development of super‐atmospheric oxidation chamber for orthodox tea processing and its validation through neural network approach
Authors: Panda Brajesh K , Chavan Ashutosh N , Datta Ashis K 
Published: January 2019

AbstractBACKGROUNDOrthodox tea is known for its distinct aroma and superior quality. However, the oxidation step that is most crucial for developing these attributes needs precise control and is also time consuming. In the present study, a super‐atmospheric oxidation chamber (SOC) was designed to address this issue. Oxidation of hand‐rolled tea leaves was performed at an elevated oxygen concentration inside the SOC. Both pressure and processing time were varied over the ranges 101–303 kPa and 0–150 min, respectively. Theaflavin (TF), thearubigin (TR) and total color (TC) were determined experimentally and then predicted through artificial neuron network (ANN) modeling.RESULTSAn increasing oxygen concentration and attainment of 100% relative humidity in the compressed air was recognized at elevated air pressure. The observed rate of formation or depletion in TF, TR and TC values was faster with compression of the ambient air. The experimental data points were predicted based on an ANN network containing 18, 10 and 16 neurons in the hidden layer since lowest mean square error and mean absolute error values were observed for the given experimental TF, TR and TC values respectively.CONCLUSIONConsidering the significant decrease in oxidation duration and minimal mechanized complexity of the design, the set‐up developed in the present study can be upscaled for industrial application in orthodox tea processing. © 2019 Society of Chemical Industry
Developing and validating a preoperative risk score to predict 90‐day mortality after liver resection
Authors: Dasari Bobby V. M. , Hodson James , Sutcliffe Robert P. , Marudanayagam Ravi , Roberts Keith J. , Abradelo Manuel , Muiesan Paolo , Mirza Darius F. , Isaac John 
Published: January 2019

BackgroundHepatobiliary surgeons continue to expand the pool of patients undergoing liver resection using combinations of surgical and interventional procedures with chemotherapy. Improved perioperative care allows for operation on higher risk surgical patients. Postoperative outcomes, including 90‐day mortality that improved over the past decade but still varies across cohorts. This study developed a preoperative risk score, on the basis significant clinical and laboratory variables, to predict 90‐day mortality after hepatectomy.MethodsAll patients who underwent hepatectomy between 2011 and 2016 were included. Univariable and multivariable analyses were performed to identify the predictors of postoperative mortality and a risk score was derived and validated.ResultsThe overall 90‐day mortality rate in the derivation cohort (n = 1269 patients) was 4.0% (N = 51). Increasing patient age (P < 0.001), extent of resection (P = 0.001), diabetes mellitus (P = 0.006), and low preoperative sodium (P = 0.012) were predictors of the increased 90‐day mortality in the multivariable analysis. The risk model developed based on these factors had an AUROC of 0.778 (P < 0.001) and remained significant in a validation cohort of 788 patients (AUROC: 0.703,
P < 0.001).ConclusionThe proposed preoperative risk score to predict 90‐day mortality after liver resection could be useful for appropriate counseling, optimization, and risk‐adjusted assessment of surgical outcomes.
Characterization of tropane and cinnamamide alkaloids from Scopolia tangutica by high‐performance liquid chromatography with quadrupole time‐of‐flight tandem mass spectrometry
Authors: Du Nana , Zhou Weijia , Jin Hongli , Liu Yanfang , Zhou Han , Liang Xinmiao 
Published: January 2019

AbstractScopolia tangutica is a traditional Chinese medicine used for antispasmodic, anesthesia, analgesia, and sedation. Its medicinal activity is associated to alkaloid constituents, including tropane and cinnamamide types. Low content of alkaloids in plant makes them difficult to be isolated and identified. The present work developed an effective method to quickly characterize alkaloids from Scopolia tangutica by high‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry. Thirteen reference compounds were studied for their fragmentation pathways, including five tropane alkaloids and eight cinnamamide ones. Alkaloid constituent was analyzed by an optimized high‐performance liquid chromatography method and mass spectrometry analysis to achieve systematic characterization of alkaloids from Scopolia tangutica. As a result, 53 compounds were identified, including 21 tropane alkaloids (eight new ones), 18 caffeoyl ones (ten new ones) and 14 dicaffeoyl ones (seven new ones). It was important to provide rich information in phytochemical study and structure‐guided isolation of important compounds from this plant.
Large‐scale separation of acetylcholinesterase inhibitors from Zanthoxylum nitidum by pH‐zone‐refining counter‐current chromatography target‐guided by ultrafiltration high‐performance liquid chromatography with ultraviolet and mass spectrometry screening
Authors: Liu Minzhuo , Liu Qi , Chen Miao , Huang Xueqian , Chen Xiaoqing 
Published: January 2019

AbstractA new strategy by converging ultrafiltration high‐performance liquid chromatography with ultraviolet and mass spectrometry and pH‐zone‐refining counter‐current chromatography was developed for the rapid screening and separation of potential acetylcholinesterase inhibitors from the crude alkaloidals extract of Zanthoxylum nitidum. An optimized two‐phase solvent system composed of chloroform/methanol/water (4:3:3, v/v) was used in this study. And, in the optimal solvent system, 45 mM hydrochloric acid was added to the aqueous stationary phase as the retainer, while 5 mM triethylamine was added to the organic mobile phase as the eluter. As a result, with the purity of over 95%, five alkaloids including jatrorrhizine (1, 340 mg), columbamine (2, 112 mg), skimmianine (3, 154 mg), palmatine (4, 226 mg), and epiberberine (5, 132 mg) were successfully purified in one step from 3.0 g crude alkaloidals extract. And their structures were identified by ultraviolet, mass spectrometry, 1H and 13C NMR spectroscopy. Notably, compounds 2, 4 and 5 were firstly reported in Z. nitidum. In addition, acetylcholinesterase inhibitory activities of compounds 1–5 were evaluated, and compounds 3, 4 and 5 exhibited stronger acetylcholinesterase inhibitory activity (IC50 values at 8.52 ± 0.64, 14.82 ± 1.21 and 3.12 ± 0.32 μg/mL, respectively) than berberine (IC50 value at 32.86 ± 2.14 μg/mL, positive control). The results indicated that the proposed method is an efficient technique to rapidly screen acetylcholinesterase inhibitors from complex samples, and could be served as a large‐scale preparative technique for separating ionizable active compounds.
Grazing and wildfire effects on small mammals inhabiting montane meadows
Authors: Horncastle Valerie J. , Chambers Carol L. , Dickson Brett G. 
Published: January 2019

ABSTRACTLivestock grazing and fire can intensively modify montane meadows. Understanding how these factors affect habitat, species richness, and diversity of small mammals can inform management decisions. Few studies have investigated the independent and synergistic effects of grazing and wildfire on vegetation and small‐mammal communities, and none have focused on montane meadows in the southwestern United States. In 2012 and 2013, we captured small mammals at 105 sites to contrast occupancy, species richness, and diversity among livestock grazing levels (present, absent), wildfire severity (unburned, low, or moderate), and meadow classifications (small or large, wet or dry) in Arizona, USA. During 13,741 trap nights, we captured 1,885 rodents of 8 species. Two species represented 88% of captures: deer mouse (Peromyscus maniculatus) and Arizona montane vole (Microtus montanus arizonensis). Deer mice, Navajo Mogollon voles (Microtus mogollonensis navaho), and thirteen‐lined ground squirrels (Ictidomys tridecemlineatus monticola; a subspecies endemic to the White Mountains, AZ) had higher occupancy in large, ungrazed meadows compared to small, grazed meadows. Species richness was greater in unburned than burned sites and small meadows than large. However, higher diversity occurred in ungrazed and dry compared to grazed and wet meadows. Three species demonstrated weak relationships between wildfire and occupancy, suggesting short‐term (<2 yrs) effects of low to moderate burn severity for these species or their habitat. Livestock grazing had a greater effect than wildfire on the small‐mammal community by altering vegetation or other habitat elements and thus decreasing population sizes. Reducing livestock grazing would benefit small‐mammal species and increase diversity and abundance of the small‐mammal community in montane meadows. © 2019 The Wildlife Society.
Application of the isotope pairing technique in sediments: Use, challenges, and new directions
Authors: Robertson Elizabeth K. , Bartoli Marco , Brüchert Volker , Dalsgaard Tage , Hall Per O. J. , Hellemann Dana , Hietanen Susanna , Zilius Mindaugas , Conley Daniel J. 
Published: January 2019

AbstractDetermining accurate rates of benthic nitrogen (N) removal and retention pathways from diverse environments is critical to our understanding of process distribution and constructing reliable N budgets and models. The whole‐core15N isotope pairing technique (IPT) is one of the most widely used methods to determine rates of benthic nitrate‐reducing processes and has provided valuable information on processes and factors controlling N removal and retention in aquatic systems. While the whole core IPT has been employed in a range of environments, a number of methodological and environmental factors may lead to the generation of inaccurate data and are important to acknowledge for those applying the method. In this review, we summarize the current state of the whole core IPT and highlight some of the important steps and considerations when employing the technique. We discuss environmental parameters which can pose issues to the application of the IPT and may lead to experimental artifacts, several of which are of particular importance in environments heavily impacted by eutrophication. Finally, we highlight the advances in the use of the whole‐core IPT in combination with other methods, discuss new potential areas of consideration and encourage careful and considered use of the whole‐core IPT. With the recognition of potential issues and proper use, the whole‐core IPT will undoubtedly continue to develop, improve our understanding of benthic N cycling and allow more reliable budgets and predictions to be made.
Use of cavity ring‐down spectrometry to quantify 13C‐primary productivity in oligotrophic waters
Authors: López‐Sandoval Daffne C. , Delgado‐Huertas Antonio , Carrillo‐de‐Albornoz Paloma , Duarte Carlos M. , Agustí Susana 
Published: January 2019

AbstractCavity ring‐down spectroscopy (CRDS) is a highly sensitive laser technique that allows the analysis of isotopic signals and absolute concentration of individual molecular species in small‐volume samples. Here, we describe a protocol to quantify photosynthetic 13C‐uptake rates of marine phytoplankton by using the CRDS technique (13C‐CRDS‐PP). We validated our method by comparing the 13C‐PP rates measured between CRDS and isotope ratio mass spectrometry (IRMS) in samples with different carbon content (30–160 μgC). The comparison revealed that 13C‐CRDS‐PP rates were highly correlated with those obtained by IRMS (Spearman correlation coefficient, ρ = 0.95, p < 0.0001, n = 15), with a mean difference between the two estimates of ± 0.08 mgC m−3 h−1. Moreover, the slope of the relationship between CRDS and IRMS results was not significantly different from 1 (F = 0.03, p = 0.86), and the intercept did not differ from 0 (F = 1.4, p = 0.24), indicating that there was no bias in the CRDS relative to the IRMS‐based measurements. A separate analysis also showed that despite the difference in volume and carbon content between samples (40 ± 10 μgC and 160 ± 40 μgC, respectively), the 13C‐CRDS‐PP technique provides similar results (Mann–Whitney test, U = 30.5, p = 0.90, n = 8). In addition, 13C‐CRDS‐PP rates measured along the Red Sea (∼ 176 mgC m−2 d−1) agreed with 14C‐based PP rates previously reported for similar locations. Thus, this study evidenced that the 13C‐CRDS‐PP method is sensitive enough to quantify carbon fixation rates in oligotrophic regions.
Metal‐Bonded Redox‐Active Triarylamines and Their Interactions: Synthesis, Structure, and Redox Properties of Paddle‐Wheel Copper Complexes
Authors: Akintola Oluseun , Böhme Michael , Rudolph Manfred , Buchholz Axel , Görls Helmar , Plass Winfried 
Published: January 2019

AbstractFour new triphenylamine ligands with different substituents in the para position and their corresponding copper(II) complexes are reported. This study includes their structural, spectroscopic, magnetic, and electrochemical properties. The complexes possess a dinuclear copper(II) paddle‐wheel core, a building unit that is also common in metal‐organic frameworks. Electrochemical measurements demonstrate that the triphenylamine ligands and the corresponding complexes are susceptible to oxidation, resulting in the formation of stable radical cations. The square‐wave voltammograms observed for the complexes are similar to those of the ligands, except for a slight shift in potential. Square‐wave voltammetry data show that, in the complexes, these oxidations can be described as individual one‐electron processes centered on the coordinated ligands. Spectroelectrochemistry reveals that, during the oxidation of the complexes, no difference can be detected for the spectra of successively oxidized species. For the absorption bands of the oxidized species of the ligands and complexes, only a slight shift is observed. ESR spectra for the chemically oxidized complexes indicate ligand‐centered radicals. The copper ions of the paddle‐wheel core are strongly antiferromagnetic coupled. DFT calculations for the fully oxidized complexes indicate a very weak ferromagnetic coupling between the copper ions and the ligand radicals, whereas a very weak antiferromagnetic coupling is found among the ligand radicals.
Designing Self‐Assembled Rosettes: Why Ammeline is a Superior Building Block to Melamine
Authors: Petelski André Nicolai , Fonseca Guerra Célia 
Published: January 2019

AbstractInvited for this month's cover picture are Professor Célia Fonseca Guerra from Vrije Universiteit Amsterdam and Leiden University (The Netherlands) and André Nicolai Petelski from UTN‐FRRe University of Argentine (Argentina). The cover picture shows a colored pallet of melamine and ammeline tautomers that form hydrogen‐bonded hexameric rosettes. When it comes to self‐assembling capabilities, one of the ammeline structures (red) is shown to be distinctly superior to melamine, both in the gas phase and in water. Quantum chemical computations explain that this is due to the presence of stronger pair interactions and the manifestation of a large cooperativity effect. Read the full text of their Full Paper at 10.1002/open.201800210.
Three‐dimensional printing of poly(lactic acid) bio‐based composites with sugarcane bagasse fiber: Effect of printing orientation on tensile performance
Authors: Liu Hao , He Hui , Peng Xiaodong , Huang Bai , Li Jiaxiong 
Published: January 2019

The cellulose fiber was extracted from the abandoned crop sugarcane bagasse (SCB) by means of chemical treatment methods. Poly(lactic acid) (PLA) bio‐based composites with SCB were prepared through fused deposition modeling (FDM) 3D‐printing technology, and the morphologies, mechanical properties, crystallization properties, and thermal stability of 3D‐printed composites were investigated. Compared with the neat PLA, the incorporation of SCB into PLA reduces the tensile strength and flexural strength of 3D‐printed samples but increases the flexural modulus. The difference in tensile performance and bending performance is that the tensile strength of 3D‐printed samples is best when the SCB content is 6 wt%, while the flexural modulus continuously decreases as the SCB content increases. Furthermore, the effects of various printing methods on the tensile performance of 3D‐printed samples were explored via modifying G‐code of 3D models. The results indicate that the optimum SCB fiber content is identical for all printing methods except method “vertical.” Due to the fibers and molecular chains are oriented to varying degrees with altering raster angle in 3D‐printed samples, the fully oriented sample printed by method “parallel” has a better tensile strength. Besides, SCB exhibits enough high thermal decomposition temperature to meet requirements for melt extrusion processing of PLA composites, and SCB fiber is capable of promoting the crystallization of PLA.
Bandgap engineered smart three‐terminal solar cell: New perspectives towards very high efficiencies in the silicon world
Authors: Djebbour Zakaria , El‐Huni Walid , Migan Dubois Anne , Kleider Jean‐Paul 
Published: January 2019

AbstractWe present the design of a new architecture of three‐terminal (3‐T) photovoltaic tandem solar cells. It combines an interdigitated back contacted (IBC) bottom lateral subcell with a heterojunction vertical top cell. In this concept, the two subcells can work independently and there is no need for tunnel junctions. It is particularly well suited to silicon back contact subcells and to various types of top cell materials from III‐V compounds or perovskites. The working principle is detailed here using as an example a p/i III‐V front stack onto n‐type silicon IBC bottom cell. We perform two‐dimensional (2D) modeling using realistic material input parameters and show how interface bandgap engineering can improve the tandem cell efficiency up to a reachable 35% value. The proposed cell concept named bandgap engineered smart silicon three‐terminal (BESTT) cell can be realized with less technological steps and at a lower cost compared with the conventional four‐terminal process.
Structure, function, and inhibition of a genomic/clinical variant of Porphyromonas gingivalis peptidylarginine deiminase
Authors: Bereta Grzegorz , Goulas Theodoros , Madej Mariusz , Bielecka Ewa , Solà Maria , Potempa Jan , Xavier Gomis‐Rüth F. 
Published: January 2019

AbstractCitrullination is an essential post‐translational modification in which the guanidinium group of protein and peptide arginines is deiminated by peptidylarginine deiminases (PADs). When deregulated, excessive citrullination leads to inflammation as in severe periodontal disease (PD) and rheumatoid arthritis (RA). Porphyromonas gingivalis is the major periodontopathogenic causative agent of PD and also an etiological agent of RA. It secretes a PAD, termed Porphyromonas PAD (PPAD), which is a virulence factor that causes aberrant citrullination. Analysis of P. gingivalis genomes of laboratory strains and clinical isolates unveiled a PPAD variant (PPAD‐T2), which showed three amino‐acid substitutions directly preceding catalytic Residue H236 (G231N/E232T/N235D) when compared with PPAD from the reference strain (PPAD‐T1). Mutation of these positions in the reference strain resulted in twofold higher cell‐associated citrullinating activity. Similar to PPAD‐T1, recombinant PPAD‐T2 citrullinated arginines at the C‐termini of general peptidic substrates but not within peptides. Catalytically, PPAD‐T2 showed weaker substrate binding but higher turnover rates than PPAD‐T1. In contrast, no differences were found in thermal stability. The 1.6 Å‐resolution X‐ray crystal structure of PPAD‐T2 in complex with the general human PAD inhibitor, Cl‐amidine, revealed that the inhibitor moiety is tightly bound and that mutations localize to a loop engaged in substrate/inhibitor binding. In particular, mutation G231N caused a slight structural rearrangement, which probably originated the higher substrate turnover observed. The present data compare two natural PPAD variants and will set the pace for the design of specific inhibitors against P. gingivalis‐caused PD.
The association between local arteriosclerosis of the prostatic arteries and chronic inflammation in human benign prostatic enlargement
Authors: Haga Nobuhiro , Akaihata Hidenori , Hata Junya , Hiraki Hiroyuki , Honda Ruriko , Tanji Ryo , Onagi Akifumi , Koguchi Tomoyuki , Hoshi Seiji , Ogawa Soichiro , Kataoka Masao , Sato Yuichi , Ishibashi Kei , Kojima Yoshiyuki 
Published: January 2019

BackgroundTo elucidate the pathogenesis of benign prostatic enlargement (BPE) in humans due to chronic inflammation caused by arteriosclerosis, the relationships between prostate size and the degree of chronic inflammation induced by local arteriosclerosis were investigated.MethodsThe present cohort included 50 subjects who underwent robot‐assisted radical prostatectomy (RARP) in a prospective study. The presence or absence of local arteriosclerosis in the prostatic arteries removed during RARP was evaluated by microscopic assessment. Chronic inflammation in the prostate was judged according to both the density and the extent of inflammatory cells. The expression of lectin‐like oxidized‐low density lipoprotein receptor‐1 (LOX‐1) and the infiltration of macrophages in the prostate, which are high in arteriosclerosis, were investigated by immunohistochemistry.ResultsLocal arteriosclerosis was observed in 28% (14/50). Prostate size and the inflammation score were significantly increased in the presence of arteriosclerosis (P = 0.006, P < 0.001, respectively). There was also a significant increase of LOX‐1 in the epithelial and stromal cells of the prostate in the presence of arteriosclerosis (all, P < 0.001). Concerning the presence of macrophages, subjects with arteriosclerosis had significantly more positive expression of ionized calcium‐binding adapter molecule‐1 (IBA‐1), a marker of macrophages, than subjects without arteriosclerosis (P < 0.001).ConclusionsIn human surgical specimens, chronic inflammation owing to local arteriosclerosis of the prostatic arteries was significantly related to prostatic enlargement. Given the immunohistochemical analyses, the putative pathogenesis for this relationship is that LOX‐1 induces macrophage infiltration, leading to BPE.