bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validated UHPLC–MS/MS method for simultaneous determination of four triterpene saponins from Akebia trifoliata extract in rat plasma and its application to a pharmacokinetic study
Authors: Chen Weikang , Zheng Yangbin , Yan Liang , Yuan Mingming , Ouyang Lan , Li Jun , Zhou Guoping , Zhong Ruijian 
Published: May 2019

AbstractSaponin PH, akemisaponins E, saponin PJ1 and scheffoleoside A, the main bioactive triterpene saponins of Chinese traditional medicine Akebia trifoliata, contribute to its diuretic pharmacological activity. Because of interactions of the multiple ingredients in vivo, pharmacokinetic studies of multiple triterpenes after administration of A. trifoliata extract are essential to clarify their pharmacological effects. The purpose of this study was to develop an efficient and sensitive UHPLC–MS/MS method for simultaneous determination of these four triterpene saponins in rat plasma. The biosamples were prepared by liquid–liquid extraction with n‐butanol. The chromatographic separation was performed on a Phenomenex Luna® C18 (150 × 2 mm, 3 μm) with a mobile phase consisting of acetonitrile and water at a flow rate of 0.5 mL/min. The MS/MS system was operated in a negative multiple reaction monitoring mode, and the precursor–product ion transitions were optimized as m/z 941.6 → 471.1 for saponin PH, 941.7 → 471.2 for akemisaponins E, 1089.7 → 601.1 for saponin PJ1, 957.6 → 487.4 for scheffoleoside A and 799.5 → 637.3 for ginsenoside Rg1 (Rg1, internal standard). Method validation parameters (calibration curve linearity, lower limit of detection, recovery, matrix effect, intra‐ and inter‐day precision) were within the acceptable ranges. This is the first reported on the UHPLC–MS/MS detection of saponin PH, akemisaponins E, saponin PJ1 and scheffoleoside A, and applied to a preclinical pharmacokinetic study after oral administration of A. trifoliata extract in rats. This study provides a basis for clinical application and further development of A. trifoliata extract.
The impact of national culture on integrated reporting quality. A stakeholder theory approach
Authors: Vitolla Filippo , Raimo Nicola , Rubino Michele , Garzoni Antonello 
Published: May 2019

AbstractIntegrated reporting (IR) is a new corporate‐reporting system that aims to represent the firm's value creation in the short, medium, and long term. In contrast to other disclosure systems focusing on non‐financial dimensions, including social and environmental aspects, IR is characterized by information connectivity. In recent years, integrated reporting has received increasing interest, both academic and professional. However, report quality is still a critical aspect of IR. Although several studies investigate IR, few focus on quality and its determinants. This study aims to fill this gap by investigating the impact of national culture, an external determinant, from a stakeholder theory perspective. The results show that IR quality is related to five dimensions of Hofstede—power distance, individualism, masculinity, and indulgence negatively and uncertainty avoidance positively. This study contributes to the relevant literature by analysing an additional factor that influences the quality of corporate reports, namely, national culture. This is the first study that investigates national culture as a determinant of integrated‐reporting quality.
Association of time interval between cancer diagnosis and initiation of palliative chemotherapy with overall survival in patients with unresectable pancreatic cancer
Authors: Lee Shu‐Hui , Chang Pei‐Hung , Chen Ping‐Tsung , Lu Chang‐Hsien , Hung Yu‐Shin , Tsang Ngan‐Ming , Hung Chia‐Yen , Chen Jen‐Shi , Hsu Hung‐Chih , Chen Yen‐Yang , Chou Wen‐Chi 
Published: May 2019

AbstractIntroductionPalliative chemotherapy is the standard treatment for patients with unresectable pancreatic cancer. Whether the early initiation of palliative chemotherapy is associated with a favorable survival outcome for these patients is not known. This study aimed to analyze the association of the time interval between cancer diagnosis and initiation of palliative chemotherapy with survival outcome in patients with pancreatic cancer.MethodA total of 838 patients with unresectable pancreatic cancer who underwent palliative chemotherapy from 2010 to 2016 at 4 institutions in Taiwan were retrospectively enrolled. All patients were categorized according to time interval between cancer diagnosis and initiation of palliative chemotherapy for comparison of the survival outcome.ResultThe median time interval was 14 days (range, 0 to 163 days) in our patient cohort. Accordingly, 22%, 29%, and 49% of the patients underwent palliative chemotherapy within 1, 1 to 2, and >2 weeks after cancer diagnosis, respectively. The survival outcome had no statistical difference among these 3 patient groups. Subgroup analyses revealed that patients with the time interval ≤2 weeks exhibited poorer survival outcome than those with the time interval >2 weeks if they initially presented with jaundice (6.1 months vs 8.4 months, P = 0.029). In contrast, patients with the time interval ≤2 weeks revealed a better survival outcome than those with the time interval >2 weeks if they initially presented with pain (8.0 vs 6.3 months, P = 0.014).ConclusionIn our study, time interval between cancer diagnosis and the initiation of palliative chemotherapy >2 weeks was not associated with a poorer survival outcome for patients with unresectable pancreatic cancer. Our result might help clinicians to clarify that early initiation of palliative chemotherapy might provide survival benefit for patients who present with tumor pain, but not for those who present with jaundice.
Salter‐Harris type II fracture of the distal femur in a newborn: Acute anatomic imaging alterations after labor dystocia
Authors: Laliotis Nicolaos , Kapetanakis Stylianos , Gkasdaris Grigorios , Konstantinidis Panagiotis , Karoutsou Ritsa , Chourmouzi Danae , Giannakopoulou Lamprini 
Published: May 2019

Key Clinical MessageA rare clinical presence of Salter‐Harris type II fracture of the distal femur in a newborn. The crucial role of imaging in depicting urgent anatomical alterations.
Hypoplastic acute myeloid leukemia in an elderly patient. A long‐term partial remission with low‐dose prednisone and G‐CSF
Authors: Islam Anwarul 
Published: May 2019

AbstractHypoplastic acute myeloid leukemia (AML) is a rare variant of AML that mainly affects the elderly and accounts for 5%‐7% of de novo AML. Prognosis for this disease is poor, and there is no standard therapy. We have treated an elderly patient with hypoplastic AML with low‐dose prednisone and G‐CSF with good results. We propose that this treatment may be a viable alternative to supportive therapy alone, or the tenuous chemotherapeutic challenge to elderly patients with hypoplastic AML.
Rapid and Quantitative Profiling of Substrate Specificity of ω‐Transaminases for Ketones
Authors: Han Sang‐Woo , Shin Jong‐Shik 
Published: May 2019

Abstractω‐Transaminases (ω‐TAs) have gained growing attention owing to their capability for asymmetric synthesis of chiral amines from ketones. Reliable high‐throughput activity assay of ω‐TAs is essential in carrying out extensive substrate profiling and establishing a robust screening platform. Here we report spectrophotometric and colorimetric methods enabling rapid quantitation of ω‐TA activities toward ketones in a 96‐well microplate format. The assay methods employ benzylamine, a reactive amino donor for ω‐TAs, as a cosubstrate and exploit aldehyde dehydrogenase (ALDH) as a reporter enzyme, leading to formation of benzaldehyde detectable by ALDH owing to concomitant NADH generation. Spectrophotometric substrate profiling of two wild‐type ω‐TAs of opposite stereoselectivity was carried out at 340 nm with 22 ketones, revealing subtle differences in substrate specificities that were consistent with docking simulation results obtained with cognate amines. Colorimetric readout for naked eye detection of the ω‐TA activity was also demonstrated by supplementing the assay mixture with color‐developing reagents whose color reaction could be quantified at 580 nm. The colorimetric assay was applied to substrate profiling of an engineered ω‐TA for 24 ketones, leading to rapid identification of reactive ketones. The ALDH‐based assay is expected to be promising for high‐throughput screening of enzyme collections and mutant libraries to fish out the best ω‐TA candidate as well as to tailor enzyme properties for efficient amination of a target ketone.
Visualization of Mass Transfer during Droplet Formation
Authors: Heine Jens Stefan , Bart Hans-Jörg 
Published: May 2019

AbstractThe impact of mass transfer in liquid‐liquid extraction during droplet formation in a quiescent continuous phase was investigated. The impact of droplet size, concentration, and formation rate on a hanging droplet was analyzed via laser induced fluorescence (LIF) using rhodamine 6G as tracer in the system of toluene and acetone in water. The droplet formation rate has a major impact on mass transfer and the mixing pattern inside the droplet. Very fast mass transfer induced by Marangoni convection was visualized at a high local resolution independently of concentration and formation rate.
Numerical Characterization of the Bubble Rise Behavior in Viscoelastic Liquids
Authors: Enders Frauke , Merker David , Kolano Markus , Böhm Lutz , Kraume Matthias 
Published: May 2019

AbstractThe bubble rise behavior in viscoelastic media is analyzed numerically with CFD. Three different constitutive models, Giesekus, linear and exponential Phan‐Thien‐Tanner, are used to evaluate three different biopolymer solutions. The terminal rise velocity over a range of bubble sizes is validated against experimental data. The local velocity fields are compared with respect to the shape and onset of the negative wake. Furthermore, the normal and shear components of the stress fields, transformed according to the local flow direction, are given. The simulations are performed with a volume of fluid solver in OpenFOAM.
Bräunungsmechanismen pflanzlicher Lebensmittel
Authors: Mai Franziska , Mertens Nils , Glomb Marcus A. 
Published: May 2019

ZusammenfassungDie vielfältigen Reaktionsmechanismen, die bei der enzymatischen Bräunung von pflanzlichen Lebensmitteln eine Rolle spielen, sind nicht allein auf die enzymkatalysierte Oxidation von phenolischen Verbindungen zurückzuführen. Neuere Untersuchungen haben zu der Einsicht geführt, dass die nach gewollter oder nicht beabsichtigter Verletzung des Pflanzengewebes einsetzende Bräunung maßgeblich auch auf anderen Vorläuferstrukturen etwa aus der Gruppe der Sesquiterpene beruht. Offensichtlich sind die Wege der Pflanzen, bei mikrobiellen Infektionen, bei tierischem Verbiss, oder dem Lagern und Verarbeiten von Lebensmitteln Abwehrstoffe zu bilden, je nach Spezies sehr unterschiedlich. Vorkommende Substrate, Spezifität und Aktivität der beteiligten Enzyme, aber evtl. auch die Art der Einwirkung auf die Pflanzenzellen können Einflussfaktoren sein. Bis heute sind kaum farbgebende Chromophore noch die dahinterstehenden Mechanismen auf strukturell molekularer Basis bekannt. Eine Ausnahme bildet die Chemie der Teefermentation, aber auch hier sind im Wesentlichen nur die ersten, niedermolekularen Verbindungen der Bräunungsreaktionen bekannt. Die Erforschung der Bräunungsmechanismen von pflanzlichen Lebensmitteln bleibt daher auch in Zukunft ein interessantes und für die Nahrungsmittelindustrie sehr wichtiges Thema.
Dysbiotic gut microbes may contribute to hypertension by limiting vitamin D production
Authors: Zuo Kun , Li Jing , Xu Qiuhua , Hu Chaowei , Gao Yuanfeng , Chen Mulei , Hu Roumu , Liu Ye , Chi Hongjie , Yin Qing , Cao Yudan , Wang Pan , Qin Yanwen , Liu Xiaoyan , Zhong Jiuchang , Cai Jun , Li Kuibao , Yang Xinchun 
Published: May 2019

AbstractBackgroundAccumulating studies have suggested that gut microbiota (GM) dysbiosis and vitamin D3 deficiency each play an important role during the progression of hypertension (HTN). However, few studies have characterized the underlying interaction between GM shift and vitamin D3 deficiency in HTN patients.HypothesisThis study aimed to evaluate the possible crosstalk between GM dysbiosis and vitamin D deficiency in the pathogenesis of HTN.MethodsIn a cohort of 34 HTN patients and 15 healthy controls, we analyzed the fecal microbiota products, GM composition, and the interaction between GM and vitamin D3.ResultsVitamin D3 was significantly decreased in feces of HTN patients (P = .006, vs controls) and was correlated with altered GM, including decreased Shannon index (R2 = 0.1296, P = .0111) and Pielou evenness (R2 = 0.1509, P = .0058). Moreover, vitamin D3 positively correlated with HTN‐reduced bacterial genera, including Subdoligranulum (R2 = 0.181, P = .0023), Ruminiclostridium (R2 = 0.1217, P = .014), Intestinimonas (R2 = 0.2036, P = .0011), Pseudoflavonifractor (R2 = 0.1014, P = .0257), Paenibacillus (R2 = 0.089, P = .0373), and Marvinbryantia (R2 = 0.08173, P = .0464). Partial least squares structural equation modeling showed that 27.7% of the total effect of gut microbiome on HTN was mediated by limiting vitamin D production. Finally, receiver operating characteristic curve analysis revealed the predictive capacity of differential gut microbiome signatures and decreased vitamin D3 to distinguish HTN patients (AUC = 0.749, P = .006).ConclusionsOur findings suggest that the GM dysbiosis contributing to the development of HTN might be partially mediated by vitamin D3 deficiency. Future studies involving the underlying mechanism and intervention strategies targeting microbiome composition and vitamin D3 to counteract the progression of HTN are warranted.
A Robust Fungal Allomelanin Mimic: An Antioxidant and Potent π‐Electron Donor with Free‐Radical Properties that can be Tuned by Ionic Liquids
Authors: Manini Paola , Lino Valeria , Franchi Paola , Gentile Gennaro , Sibillano Teresa , Giannini Cinzia , Picardi Emanuela , Napolitano Alessandra , Valgimigli Luca , Chiappe Cinzia , d'Ischia Marco 
Published: May 2019

AbstractDeveloping effective strategies to increase the chemical stability and to fine‐tune the physico‐chemical properties of melanin biopolymers by rational control of π‐electron conjugation is an important goal in materials science for biomedical and technological applications. Herein we report that poly‐1,8‐dihydroxynaphthalene (pDHN), a non‐nitrogenous, catechol‐free fungal melanin mimic, displays a high degree of structural integrity (from MALDI‐MS and CP/MAS 13C NMR analysis), a strong radical scavenging capacity (DPPH and FRAP assays), and an unusually intense EPR signal (g=2.0030). Morphological and spectral characterization of pDHN, along with deassembly experiments in ionic liquids, indicated amorphous aggregates of small globular structures with an estimated stacking distance of 3.9 Å and broadband absorption throughout the visible range. These results indicate that DHN‐based melanins exhibit a high structural integrity and enhanced antioxidant and free‐radical properties of potentially greater biomedical and technological relevance than for typical indole‐based eumelanins.
The Palladium‐Catalyzed Carboxytelomerization of Butadiene with Agrobased Alcohols and Polyols
Authors: Wilson Emma , Dumont Clément , Drelon Mathieu , Suisse Isabelle , Penverne Christophe , Sauthier Mathieu 
Published: May 2019

AbstractThe palladium catalyzed carboxytelomerization reaction of alcohols with butadiene allows for efficient and atom‐economical access to unsaturated alkyl nona‐3,8‐dienoate esters. The study focused on the nature of the catalyst (phosphine and acid) with ethanol. Commercially available triarylphosphines and carboxylic acids associated with a simple palladium precursor appear to be the best combination for in situ generation of the catalyst. The reaction conditions were further optimized and the carboxytelomerization reaction was efficiently applied to the full transformation of several industrially relevant agro‐based monoalcohols and polyols.
Concatenation of polar codes with three‐dimensional parity check (3D‐PC) codes to improve error performance over fading channels
Authors: Jasim Ibrahim Beram , Bayat Oguz , Ucan Osman N. 
Published: May 2019

SummaryIn this paper, we concatenated of three‐dimensional parity check (3D‐PC) block and polar codes for improving error correction performance and bit error rate (BER). Three different sizes of 3D parity check blocks (4 × 4 × 4, 8 × 8 × 8, and 16 × 16 × 16) are used for polar code concatenation. The 4 × 4 × 4 block returns the best performance, but higher complexity of decoder is needed unlikely. The 8 × 8 × 8 has returned acceptable complexity and good performacne. The complexity of decoder is less in the case of 16 × 16 × 16 with slight performance. The performance of the 3D‐PC is reduced when the codewords length is increased. The experiment considered the presence of additive white Gaussian noise (AWGN) with Rayleigh and Rician fading environments. 3D‐PC and polar code concatenation is more precise with codewords of short length, whereas there is insufficient concatenation accuracy with longer codewords. The outcomes of this study contain comparison between AWGN, Rayleigh, and Rician environments. The AWGN is noticed to have a lesser negative impact on the performance of code. Furthermore, increasing the code length may slightly fill the gap of performance between the concatenated and none concatenated polar codes due to the impact of code length on parity check code performance. Simulation results showed the coding performance in case of the polar code with concatenation and without concatenation for different code lengths. Generally, the 3D‐PC polar code concatenation is drawn the optimal result in AWGN environments.
A cognitive network management system to improve QoE in stereoscopic IPTV service
Authors: Cánovas Alejandro , Taha Miran , Lloret Jaime , Tomas Jesús 
Published: May 2019

SummaryNew Internet Protocol Television (IPTV) services are including new technologies such as Stereoscopic TV and three‐dimensions (3D) HDTV. As well, increased ubiquitous networking and promoting in smart devices have led to high demand IPTV (over networks). Stereoscopic content required higher data flow to support these emerging TV services, and there are higher requirements at the network layer to provide good quality of service and quality of experience to the end users in delivering stereoscopic IPTV. In this paper, we propose a new concept of cognitive network management algorithm and protocol based on 3D coding techniques for delivering of stereoscopic IPTV service. The proposed approach explains how the management algorithm observes the network performance to guarantee the quality of the stereoscopic IPTV services, by measuring the performance of quality of service (QoS) parameters (delay, jitter, and packets loss) and quality of experience (QoE) metrics such as Peak Signal‐to‐Noise Ratio (PSNR), Moving Image Videography (MIV), and Mean Opinion Score (MOS). Those parameters are monitored in order to take appropriate codification decision for IPTV service provider. Moreover, the codification decision uses K‐mean classification to select the better codification for the end users. Therefore, both kinds of 3D coding formats such as Stereo Video Coding (SVC) format and 2D + Z Coding format (2D‐plus‐Depth) are selected in our experiments. As a result, our proposal successfully ensures the appropriate quality of service and quality of experience to the end users when the service of stereoscopic IPTV is being delivered.
Phenological mismatch in Arctic‐breeding shorebirds: Impact of snowmelt and unpredictable weather conditions on food availability and chick growth
Authors: Saalfeld Sarah T. , McEwen Daniel C. , Kesler Dylan C. , Butler Malcolm G. , Cunningham Jenny A. , Doll Andrew C. , English Willow B. , Gerik Danielle E. , Grond Kirsten , Herzog Patrick , Hill Brooke L. , Lagassé Benjamin J. , Lanctot Richard B. 
Published: May 2019

AbstractThe ecological consequences of climate change have been recognized in numerous species, with perhaps phenology being the most well‐documented change. Phenological changes may have negative consequences when organisms within different trophic levels respond to environmental changes at different rates, potentially leading to phenological mismatches between predators and their prey. This may be especially apparent in the Arctic, which has been affected more by climate change than other regions, resulting in earlier, warmer, and longer summers. During a 7‐year study near Utqiaġvik (formerly Barrow), Alaska, we estimated phenological mismatch in relation to food availability and chick growth in a community of Arctic‐breeding shorebirds experiencing advancement of environmental conditions (i.e., snowmelt). Our results indicate that Arctic‐breeding shorebirds have experienced increased phenological mismatch with earlier snowmelt conditions. However, the degree of phenological mismatch was not a good predictor of food availability, as weather conditions after snowmelt made invertebrate availability highly unpredictable. As a result, the food available to shorebird chicks that were 2–10 days old was highly variable among years (ranging from 6.2 to 28.8 mg trap−1 day−1among years in eight species), and was often inadequate for average growth (only 20%–54% of Dunlin and Pectoral Sandpiper broods on average had adequate food across a 4‐year period). Although weather conditions vary among years, shorebirds that nested earlier in relation to snowmelt generally had more food available during brood rearing, and thus, greater chick growth rates. Despite the strong selective pressure to nest early, advancement of nesting is likely limited by the amount of plasticity in the start and progression of migration. Therefore, long‐term climatic changes resulting in earlier snowmelt have the potential to greatly affect shorebird populations, especially if shorebirds are unable to advance nest initiation sufficiently to keep pace with seasonal advancement of their invertebrate prey.
Using lake sediment archives to improve understanding of flood magnitude and frequency: Recent extreme flooding in northwest UK
Authors: Chiverrell R.C. , Sear D.A. , Warburton J. , Macdonald N. , Schillereff D.N. , Dearing J.A. , Croudace I.W. , Brown J. , Bradley J. 
Published: May 2019

AbstractWe present the first quantitative reconstruction of palaeofloods using lake sediments for the UK and show that for a large catchment in NW England the cluster of devastating floods from 1990 to present is without precedent in this 558‐year palaeo‐record. Our approach augments conventional flood magnitude and frequency (FMF) analyses with continuous lake sedimentary data to provide a longer‐term perspective on flood magnitude recurrence probabilities. The 2009 flood, the largest in >558 years, had a recurrence interval larger (1:2,200 year) than revealed by conventional flood estimation using shorter duration gauged single station records (1:1,700 year). Flood‐rich periods are non‐stationary in their correlation with climate indices, but the 1990‐2018 cluster is associated with warmer Northern Hemisphere Temperatures and positive Atlantic Multidecadal Oscillation. Monitored records rarely capture the largest floods and our palaeoflood series shows, for this catchment, such omissions undermine evaluations of future risk. Our approach provides an exemplar of how to derive centennial palaeoflood reconstructions from lakes coupled well with their catchments around the world. © 2019 The Authors. Earth Surface Processes and Landforms Published by John Wiley & Sons Ltd.