bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isolation of the major chiral compounds from Bubonium graveolens essential oil by HPLC and absolute configuration determination by VCD
Authors: Said Mohammed El‐Amin , Bombarda Isabelle , Naubron Jean‐Valère , Vanloot Pierre , Jean Marion , Cheriti Abdelkrim , Dupuy Nathalie , Roussel Christian 
Published: December 2016

AbstractThe chirality issues in the essential oils (EOs) of leaves and flowers from Bubonium graveolens were addressed by chiral high‐performance liquid chromatography (HPLC) with polarimetric detection and vibrational circular dichroism (VCD). The chemical compositions of the crude oils of three samples were established by gas chromatography / mass spectrometry (GC/MS). The well‐known cis‐chrysanthenyl acetate (1), oxocyclonerolidol (2), and the recently disclosed cis‐acetyloxychrysanthenyl acetate (3), the three major chiral compounds, were isolated by preparative HPLC. The naturally occurring oxocycloneroledol (2), mostly found in the leaf oil (49.4–55.6%), presents a (+) sign in the mobile phase during HPLC on a chiral stationary phase (CSP) with a Jasco polarimetric detection. The naturally occurring cis‐chrysanthenyl acetate (1) and cis‐acetyloxychrysanthenyl acetate (3), mostly found in the flower EO (35.9–74.9% and 10.0–34.3%, respectively), both present a (−) sign. HPLC on a CSP with polarimetric detection is an unprecedented approach to readily differentiate the flower and leaf EOs according to their chiral signature. The comparison of the experimental and calculated VCD spectra of pure isolated 1, 2, and 3 provided their absolute configuration as being (1S,5R,6S)‐(−)‐2,7,7‐trimethylbicyclo[3.1.1]hept‐2‐en‐6‐yl acetate 1, (2R,6R)‐(+)‐6‐ethenyl‐2,6‐dimethyl‐2‐(4‐methylpent‐3‐en‐1‐yl)dihydro‐2H‐pyran‐3(4H)‐one) 2 and (1S,5R,6R,7S)‐(−)‐7‐(acetyloxy)‐2,6‐dimethylbicyclo[3.1.1]hept‐2‐en‐6‐yl]methyl acetate 3. Compounds 1, 2, and 3 were already known in B. graveolens but this is the first report of the absolute configuration of (+)‐2 and (−)‐3. The VCD chiral signatures of the crude oils were also recorded.
Tuning the Electron‐Transport and Electron‐Accepting Abilities of Dyes through Introduction of Different π‐Conjugated Bridges and Acceptors for Dye‐Sensitized Solar Cells
Authors: Li Yuanzuo , Sun Chaofan , Song Peng , Ma Fengcai , Yang Yanhui 
Published: December 2016

AbstractA series of dyes, containing thiophene and thieno[3,2‐b]thiophene as π‐conjugated bridging units and six kinds of groups as electron acceptors, were designed for dye‐sensitized solar cells (DSSCs). The ground‐ and excited‐state properties of the designed dyes were investigated by using density functional theory (DFT) and time‐dependent DFT, respectively. Moreover, the parameters affecting the short‐circuit current density and open‐circuit voltage were calculated to predict the photoelectrical performance of each dye. In addition, the charge difference density was presented through a three‐dimensional (3D) real‐space analysis method to investigate the electron‐injection mechanism in the complexes. Our results show that the longer conjugated bridge would inhibit the intramolecular charge transfer, thereby affecting the photoelectrical properties of DSSCs. Similarly, owing to the lowest chemical hardness, largest electron‐accepting ability, dipole moment (
) and the change in the energy of the TiO2 conduction band (
), the dye with a (E)‐3‐(4‐(benzo[c][1,2,5]thiadiazol‐4‐yl)phenyl)‐2‐cyanoacrylic acid (TCA) acceptor group would exhibit the most significant photoelectrical properties among the designed dyes.
Towards Storage of Solar Energy in Photochromic Molecules: Benzannulation of the Dihydroazulene/Vinylheptafulvene Couple
Authors: Skov Anders B. , Petersen Johannes F. , Elm Jonas , Frandsen Benjamin N. , Santella Marco , Kilde Martin Drøhse , Kjaergaard Henrik G. , Mikkelsen Kurt V. , Nielsen Mogens Brøndsted 
Published: December 2016

AbstractOne challenge in the development of molecular photoswitches for solar energy storage is to increase the energy of the isomer formed upon irradiation. This work focuses on how to affect the relative stabilities of the isomers of the dihydroazulene/ vinylheptafulvene (DHA/VHF) couple by combining the light‐induced DHA to VHF conversion with the loss of aromaticity. We present a synthetic procedure for benzannulation of DHA at the C7−C8 bond, with the key steps being a stereoselective Diels–Alder cycloaddition followed by an oxidation. The optical properties and switching abilities of this compound are described in a combined theoretical and experimental study. Calculations support that benzannulation serves to increase the overall energy capacity of the photoswitch by stabilizing the DHA and destabilizing the VHF.
Infant hair cortisol: associations with salivary cortisol and environmental context
Authors: Flom Megan , St. John Ashley M. , Meyer Jerrold S. , Tarullo Amanda R. 
Published: December 2016

AbstractEarly chronic stress has enduring implications for physical and mental health outcomes. Hair cortisol concentration (HCC) has emerged as a marker of cumulative cortisol exposure, yet HCC in infants is not well understood. We examined how infant HCC relates to widely used basal salivary cortisol measures, maternal HCC, and environmental context in 111 infants assessed at 6 and 12 months of age. Maternal HCC at 6 and 12 months was correlated with infant HCC at 12 months. At 12 months, infant HCC was positively associated with waking salivary cortisol concentration (SCC), evening SCC, and area under the curve (AUC), but was independent of diurnal slope. Breastfeeding was associated with lower HCC, whereas increased sleep disruption was related to flatter slope. Reduced nighttime sleep duration was related both to higher HCC and to flatter slope. A person‐focused analysis indicated that the combination of high HCC and flattened slope was associated with more environmental risks, highlighting the importance of investigating the interplay between HCC and diurnal cortisol slope. Results support the validity of HCC as a marker of cumulative cortisol exposure in infancy, while emphasizing the value of including multiple cortisol measures assessing distinct aspects of hypothalamic–pituitary–adrenal (HPA) function.
A sensitive assay for urinary cocaine metabolite benzoylecgonine shows more positive results and longer half‐lives than those using traditional cut‐offs
Authors: Nickley Joyce , Pesce Amadeo J. , Krock Kevin 
Published: December 2016

Cocaine is a common drug of abuse. To detect its use, a screening detection concentration for the cocaine metabolite benzoylecgonine is commonly set at 150 ng/mL and its confirmatory cut‐off is set at 100 ng/mL. Studies have suggested that these cut‐offs may be set too high, allowing some patients with this substance abuse problem to be missed or improperly monitored. With the advent of liquid chromatography–tandem mass spectrometry (LC–MS/MS) technology it is possible to reliably detect and quantify lower concentrations of its metabolite benzoylecgonine as part of a larger drug panel. One purpose of the study was to establish if there was a significant increase in detection of cocaine use with a ten‐fold more sensitive cut‐off. A very sensitive dilute and shoot assay for benzoylecgonine was developed with a lower limit of quantitation of 5 ng/mL. Validation of the 5 ng/mL cut‐off was achieved by plotting all the positive cocaine observations as a frequency distribution on a logarithmic scale. The number of positive results with measurable concentrations below the typical industry 100 ng/mL cut‐off level but above the high sensitivity 5 ng/mL cut‐off level was observed to be 51.9% of the observed positives. The lower cut‐off also allowed a re‐evaluation of the window of detection after cessation of use. It was observed to be between 17 and 22 days. © 2016 Precision Diagnostics, LLC. Drug Testing and Analysis published by John Wiley & Sons, Ltd.
Cryptic female Strawberry poison frogs experience elevated predation risk when associating with an aposematic partner
Authors: Segami Marzal Julia Carolina , Rudh Andreas , Rogell Björn , Ödeen Anders , Løvlie Hanne , Rosher Charlotte , Qvarnström Anna 
Published: December 2016

AbstractPopulation divergence in sexual signals may lead to speciation through prezygotic isolation. Sexual signals can change solely due to variation in the level of natural selection acting against conspicuousness. However, directional mate choice (i.e., favoring conspicuousness) across different environments may lead to gene flow between populations, thereby delaying or even preventing the evolution of reproductive barriers and speciation. In this study, we test whether natural selection through predation upon mate‐choosing females can favor corresponding changes in mate preferences. Our study system, Oophaga pumilio, is an extremely color polymorphic neotropical frog with two distinctive antipredator strategies: aposematism and crypsis. The conspicuous coloration and calling behavior of aposematic males may attract both cryptic and aposematic females, but predation may select against cryptic females choosing aposematic males. We used an experimental approach where domestic fowl were encouraged to find digitized images of cryptic frogs at different distances from aposematic partners. We found that the estimated survival time of a cryptic frog was reduced when associating with an aposematic partner. Hence, predation may act as a direct selective force on female choice, favoring evolution of color assortative mating that, in turn, may strengthen the divergence in coloration that natural selection has generated.
Structural analysis of phosphatidylcholine using a thin layer chromatography‐based method
Authors: Tan Guiwei , Tian Yinggang , Addy Min , Cheng Yanling , Xie Qinglong , Zhang Bo , Liu Yuhuan , Chen Paul , Ruan Roger 
Published: December 2016

In this study, a novel technique for positional analysis of phosphatidylcholine (PC) was developed and investigated. This technique is based on a well‐defined connection between two‐dimensional chromatography and in situ enzymatic hydrolysis. Characterizations of PC composition mainly occurred on a thin layer chromatography (TLC) plate. This method could reveal the relative percentage of each fatty acyl residue on the sn‐1 and sn‐2 ester linkages of PC, respectively. PC was isolated from total lipids by TLC, and then its purity was confirmed by high performance liquid chromatography (HPLC). Without further extraction from the TLC plate, PC was directly hydrolyzed by phospholipases on the plate. A PLA1 enzyme loading of 0.12 mL appeared to be optimum for the in situ enzymatic hydrolysis of PC, with an 87.7% PC conversion; while for a PLA2 enzyme loading of 0.30 mL, the PC conversion was 84.8%. From HPLC, no acyl migration was observed above the HPLC detection limit in both in situ enzymatic hydrolysis reactions. Free fatty acids (FFAs) released from different positions of the PC were isolated from the product mixture by two‐dimensional chromatography. The FFAs bands were chemically trans‐esterified into fatty acids methyl ester (FAMEs) and analyzed by GC‐MS to uncover the PC positional structure.Practical applications: This study developed a new method to directly perform enzymatic hydrolysis reaction on a TLC plate. With a connection between two‐dimensional chromatography and in situ enzymatic hydrolysis, a TLC plate can play multiple roles, including a separation tool, an enzymatic reaction carrier, and an identification tool. Thus, TLC technique has high potential and this study helped extend its applications.Step 1: Total lipids were applied to a thin layer chromatography (TLC) plate, and then phosphatidylcholine (PC) is separated from other lipids. Step 2: Enzyme solution and wetting agent are applied to the PC band. Step 3: After in situ enzymatic reaction, PC is partly hydrolyzed into lysophosphatidylcholine (LPC) and free fatty acids (FFAs), and the hydrolysis rate are 87.7% (with 0.12 mL PLA1 enzyme) and 84.8% (with 0.30 mL PLA2 enzyme), respectively. Step 4: The TLC plate is rotated by 90°. Step 5: The FFAs released from PC are isolated from products mixtures by a second‐dimensional chromatography.
Assessing and managing multiple risks in a changing world—The Roskilde recommendations
Authors: Selck Henriette , Adamsen Peter B. , Backhaus Thomas , Banta Gary T. , Bruce Peter K.H. , Burton G. Allen , Butts Michael B. , Boegh Eva , Clague John J. , Dinh Khuong V. , Doorn Neelke , Gunnarsson Jonas S. , Hauggaard-Nielsen Henrik , Hazlerigg Charles , Hunka Agnieszka D. , Jensen John , Lin Yan , Loureiro Susana , Miraglia Simona , Munns Wayne R. , Nadim Farrokh , Palmqvist Annemette , Rämö Robert A. , Seaby Lauren P. , Syberg Kristian , Tangaa Stine R. , Thit Amalie , Windfeld Ronja , Zalewski Maciej , Chapman Peter M. 
Published: December 2016

Abstract

Roskilde University (Denmark) hosted a November 2015 workshop, Environmental Risk—Assessing and Managing Multiple Risks in a Changing World. This Focus article presents the consensus recommendations of 30 attendees from 9 countries regarding implementation of a common currency (ecosystem services) for holistic environmental risk assessment and management; improvements to risk assessment and management in a complex, human-modified, and changing world; appropriate development of protection goals in a 2-stage process; dealing with societal issues; risk-management information needs; conducting risk assessment of risk management; and development of adaptive and flexible regulatory systems. The authors encourage both cross-disciplinary and interdisciplinary approaches to address their 10 recommendations: 1) adopt ecosystem services as a common currency for risk assessment and management; 2) consider cumulative stressors (chemical and nonchemical) and determine which dominate to best manage and restore ecosystem services; 3) fully integrate risk managers and communities of interest into the risk-assessment process; 4) fully integrate risk assessors and communities of interest into the risk-management process; 5) consider socioeconomics and increased transparency in both risk assessment and risk management; 6) recognize the ethical rights of humans and ecosystems to an adequate level of protection; 7) determine relevant reference conditions and the proper ecological context for assessments in human-modified systems; 8) assess risks and benefits to humans and the ecosystem and consider unintended consequences of management actions; 9) avoid excessive conservatism or possible underprotection resulting from sole reliance on binary, numerical benchmarks; and 10) develop adaptive risk-management and regulatory goals based on ranges of uncertainty. Environ Toxicol Chem 2017;36:7–16. © 2016 SETAC
Test–retest reliability and concurrent validity of in vivo myelin content indices: Myelin water fraction and calibrated T1w/T2w image ratio
Authors: Arshad Muzamil , Stanley Jeffrey A. , Raz Naftali 
Published: December 2016

AbstractIn an age‐heterogeneous sample of healthy adults, we examined test–retest reliability (with and without participant repositioning) of two popular MRI methods of estimating myelin content: modeling the short spin–spin (T2) relaxation component of multi‐echo imaging data and computing the ratio of T1‐weighted and T2‐weighted images (T1w/T2w). Taking the myelin water fraction (MWF) index of myelin content derived from the multi‐component T2relaxation data as a standard, we evaluate the concurrent and differential validity of T1w/T2w ratio images. The results revealed high reliability of MWF and T1w/T2w ratio. However, we found significant correlations of low to moderate magnitude between MWF and the T1w/T2w ratio in only two of six examined regions of the cerebral white matter. Notably, significant correlations of the same or greater magnitude were observed for T1w/T2w ratio and the intermediate T2relaxation time constant, which is believed to reflect differences in the mobility of water between the intracellular and extracellular compartments. We conclude that although both methods are highly reliable and thus well‐suited for longitudinal studies, T1w/T2w ratio has low criterion validity and may be not an optimal index of subcortical myelin content.Hum Brain Mapp 38:1780–1790, 2017. ©2017 Wiley Periodicals, Inc.
Building Robots and Story‐Based Learning to Teach Cyber‐Physical Systems Effectively to Any Class of Audiences ranging from Elementary School Students to University Graduates
Authors: Seya Keisuke , Shirasaka Seiko 
Published: December 2016

AbstractThe Cyber‐Physical Systems (CPS) has attracted large attention from a wide variety of audiences such as academia, industry, and news media. That's because it is considered a key enabler of our future technologies. The governments of various countries have realized its importance and hammered out long‐term visions to invest their resources (i.e. time and money) to urge the growth of the CPS industry. In order to increase the number of people who can work in this industry, the demand searching for a new way of teaching CPS to different classes of people has emerged naturally. In order to help both learners and educators, we've developed a story‐based educational system for CPS that is extremely adaptable to any class of learners; it guides the learners to understand the CPS by building their own robot. In this paper, we describe the theory behind its design and discuss the effectiveness of this approach.
Streaming analytics for real‐time and data‐driven decision making in Automation Industry
Authors: Maganti Ramesh , Swamy Manjunatha 
Published: December 2016

AbstractWith disruptive technologies such as IoT, pervasive computing and drones, automation is spreading to every process from house hold to large industry, with that tremendous amount of data being generated from multiple systems and sub systems. Tons of valuable critical data is available, there is need for live analysis and actionable insights for process improvements and controls. Traditional analytics method such as data‐mining, ETL (Extract, Transform, Load) with batch processing and delayed insights, are becoming more and more irrelevant. There is a stressing need for real‐time and data‐driven decision making.Streaming analytics is getting in to fast lane, to analyse multiple streams of data, events generated by components across the physical spectrum to generate real‐time insights. With machine learning and artificial intelligence trends, there is huge scope to generate learning models from historical data and provide predictive analysis out of real‐time data streams to automate the decision making process.
Proof of Concept on Application of Formal Methods at different phases of development cycle of Avionics Software A Landscaping
Authors: Mitra Raka , Jayakumar SS , Kishore Koyalkar Raman 
Published: December 2016

AbstractFormal Methods comprises of mathematical representation of an embedded system and its system requirements or its corresponding software High Level Requirements (HLRs) and /or software Low Level Requirements (LLRs). When a system and its requirements which dictate its behavior or performance characteristics are expressed as mathematical entities by different mathematical formalisms, it makes a case for carrying out Formal Analysis and Formal Verification of the system to confirm that it behaves as it is expected under all possible scenarios of its execution, for all times. In other words, such formal techniques guarantee absence of errors in the system behavior every time it is made to execute, unlike testing which only exposes presence of defects and not its absence. In this paper we have presented the set of Proof OF Concept Exercises we have carried out on Formal Verification of Avionics Systems, for compliance with DO 178C/DO 333 objectives. Also, this paper talks about the few challenges encountered for the application of Formal Methods in real projects
Comparative study of presurgical skin infiltration depth measurements of melanocytic lesions with OCT and high frequency ultrasound
Authors: Varkentin Arthur , Mazurenka Mikhail , Blumenröther Elias , Meinhardt‐Wollweber Merve , Rahlves Maik , Broekaert Sigrid M. C. , Schäd‐Trcka Susanne , Emmertinst Steffen , Morgner Uwe , Roth Bernhard 
Published: December 2016

A reliable, fast, and non‐invasive determination of melanoma thickness in vivo is highly desirable for clinical dermatology as it may facilitate the identification of surgical melanoma margins, determine if a sentinel node biopsy should be performed or not, and reduce the number of surgical interventions for patients. In this work, optical coherence tomography (OCT) and high frequency ultrasound (HFUS) are evaluated for quantitative in vivo preoperative assessment of the skin infiltration depth of melanocytic tissue. Both methods allow non‐invasive imaging of skin at similar axial resolution. Comparison with the Breslow lesion thickness obtained from histopathology revealed that OCT is slightly more precise in terms of thickness determination while HFUS has better contrast. The latter does not require image post‐processing, as necessary for the OCT images. The findings of our pilot study suggest that non‐invasive OCT and HFUS are able to determine the infiltration depth of lesions like melanocytic nevi or melanomas preoperatively and in vivo with a precision comparable to invasive histopathology measurements on skin biopsies. In future, to further strengthen our findings a statistically significant study comprising a larger amount of data is required which will be conducted in an extended clinical study in the next step.
Comparison of optical coherence tomography and high frequency ultrasound B‐Scans and a H&E stained histology of a melanocytic nevus.magnified imageComparison of optical coherence tomography and high frequency ultrasound B‐Scans and a H&E stained histology of a melanocytic nevus.
Diagnostics of femoral head status in humans using laser spectroscopy – In vitro studies
Authors: Lin Huiying , Li Wansha , Zhang Hao , Chen Peng , Chen Delong , He Wei , Svanberg Sune , Svanberg Katarina 
Published: December 2016

Osteonecrosis of the femoral head (ONFH), a recalcitrant and disabling disease, is caused by inadequate or fully disrupted blood supply to the affected segment of the subchondral bone. Theoretically, there will develop gas‐filled pores during the bone decay process due to lacking blood supply. Unfortunately, the relationship between the gas‐filled pores and ONFH is still unclear. Here, we have introduced diode laser absorption spectroscopy to detect oxygen and water vapor signals in the femoral heads from hip replacement in 19 patients. Five samples are affected by osteoarthritis (OA) and the others are related to ONFH. Oxygen and water vapor signals could be obtained, demonstrating the presence of gas‐filled pores in both the OA and ONFH groups while the measurement results showed no significant difference. A study of gas exchange was also performed on one excised bone sample to study how these gas pores communicate with the ambient air. The results suggested that the obtained oxygen signals inside the bone samples originate from the invasion of ambient air, which is not expected in vivo. In conclusion, the ability to detect the gas signal of laser absorption spectroscopy shows the potential for the medical application of assessing the human femoral head in vivo.
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