bluuebunny/crossref_metadata_2025 huggingface dataset:
Supported palladium nanoparticle‐catalysed Suzuki–Miyaura cross‐coupling approach for synthesis of aminoarylbenzosuberene analogues from natural precursor
Authors: Bharti Richa , Bal Reddy C. , Kumar Sandeep , Das Pralay
Published: March 2017

A semi‐synthetic method has been developed for the synthesis of aminoarylbenzosuberenes (AABs) from naturally occurring himachalenes, an isomeric mixture of sesquiterpenes present in Cedrus deodara oil. Polymer‐stabilized Pd(0) nanoparticle‐catalysed Suzuki–Miyaura cross‐coupling reaction of aminovinyl bromide‐substituted benzosuberenes has been adopted for AAB synthesis. The catalyst performed well with different amine substituents, and was recycled up to five times. The synthesis of such arylated benzosuberene class of compounds from natural precursors following semi‐synthetic approaches could provide an attractive alternative method with reduced number of steps.
A novel assay to determine acetylcholinesterase activity: The application potential for screening of drugs against Alzheimer's disease
Authors: Peng Liang , Rong Zhengxing , Wang Hao , Shao Biyun , Kang Lei , Qi Hong , Chen Hongzhuan
Published: March 2017

Acetycholinesterase (AChE) that regulates hydrolysis of acetylcholine (ACh) in the brain, is an important target for treatment of Alzheimer's disease (AD), a feature of which is ACh deficiency. However, the methods to precisely determine AChE activity are still under development. We developed a new method to exploit acetylcholine‐d4 as a surrogate substrate of ACh and measure product choline‐d4 via liquid chromatography–tandem mass spectrometry (LC–MS/MS). This assay detected activity of AChE present in the normal mouse brain, which is consistent with the standard Ellman assay that determines products spectrophotometrically. In AD mouse models, the result of LC–MS/MS assay showed significant higher AChE activity than that seen in control normal mice, while treatment of AD mice with an AChE inhibitor, huperzine A, led to partial decreases in AChE activity. Our results suggest that this surrogate‐based LC–MS/MS method is a new, sensitive and convenient assay for the determination of AChE activity, providing a useful means for screening active compounds that target AChE.
The influence of wrist posture, grip type, and grip force on median nerve shape and cross‐sectional area
Authors: Cowley Jeffrey C. , Leonardis Joshua , Lipps David B. , Gates Deanna H.
Published: March 2017

During grasping, the median nerve undergoes mechanical stress in the carpal tunnel which may contribute to carpal tunnel syndrome. This study investigated the effects of wrist posture, grip type, and grip force on the shape and cross‐sectional area of the median nerve. Ultrasound examination was used to obtain cross‐sectional images of the dominant wrist of 16 healthy subjects (8 male) at the proximal carpal tunnel during grasping. The cross‐sectional area, circularity, and axis lengths of the median nerve were assessed in 27 different conditions (3 postures × 3 grip types × 3 force levels). There were no significant changes in median nerve cross‐sectional area (P > 0.05). There were significant interactions across posture, grip type, and grip force affecting nerve circularity and axis lengths. When the wrist was flexed, increasing grip force caused the median nerve to shorten in the mediolateral direction and lengthen in the anteroposterior direction (P < 0.04), becoming more circular. These effects were significant during four finger pinch grip and chuck grip (P < 0.05) but not key grip (P > 0.07). With the wrist extended, the nerve became more flattened (less circular) as grip force increased during four finger pinch grip and chuck grip (P < 0.04) but not key grip (P > 0.3). Circularity was lower during the four finger pinch compared to chuck or key grip (P < 0.03). The findings suggest that grip type and wrist posture significantly alter the shape of the median nerve. Clin. Anat. 30:470–478, 2017. © 2017 Wiley Periodicals, Inc.
Halogen‐Bonding Interactions of Polybrominated Diphenyl Ethers and Thyroid Hormone Derivatives: A Potential Mechanism for the Inhibition of Iodothyronine Deiodinase
Authors: Marsan Eric S. , Bayse Craig A.
Published: March 2017

Polybrominated diphenyl ethers (PBDEs) increase flame resistance in consumer goods, but these compounds and their hydroxylated derivatives (OH‐BDEs) impair normal thyroid function. Halogen bonding (XB) of PBDEs to an active site selenocysteine may prevent iodothyronine deiodinase(Dio)‐catalyzed activation/deactivation of thyroid hormone (TH) derivatives. In this study, we compare the strength of the XB interactions of TH derivatives, iodine‐based contrast agents and PBDEs/OH‐BDEs with a methylselenolate model of the Dio active site using density functional theory calculations. The strength of the XB interaction depends upon the acceptor halide, the position of the halide, the number of ring substituents, and the proximity of hydroxyl groups to the XB site. The weaker Se⋅⋅⋅Br interactions relative to Se⋅⋅⋅I interactions are consistent with a model of competitive inhibition that blocks binding of THs at elevated PBDE/OH‐BDE concentrations. XB interactions were generally more favorable at ortho and meta positions and in substrates with more electron‐withdrawing substituents. PBDEs/OH‐BDEs that mimic the binding behavior of THs, that is, containing ortho and meta bromides and adjacent hydroxyl groups, may be the most effective inhibitors. Highly‐brominated PBDEs/OH‐BDEs have comparable interaction energies to THs and may undergo debromination. These results may also suggest that XB strength must exceed a threshold value in order for PBDEs/OH‐BDEs to undergo nucleophilic attack by Dio.
Stereocontrolled Synthesis of Amino‐Substituted Carbocycles by Pd‐Catalyzed Alkene Carboamination Reactions
Authors: White Derick R. , Wolfe John P.
Published: March 2017

Amino‐substituted alkylidenecyclopentanes were synthesized through a stereoselective intermolecular Pd‐catalyzed alkene carboamination reaction between alkenyl triflates bearing a pendant alkene and exogenous amine nucleophiles. The reactions are effective with a range of different substrate combinations, and proceed with generally high diastereoselectivity. Use of (S)‐tBuPhox as the ligand in reactions of achiral substrates provides enantioenriched products with up to 98.5:1.5 e.r.
Anterior and posterior parts of the rat ventral tegmental area and the rostromedial tegmental nucleus receive topographically distinct afferents from the lateral habenular complex
Authors: Petzel Anja , Bernard René , Poller Wolfram C. , Veh Rüdiger W.
Published: March 2017

That activation of the reward system involves increased activity of dopaminergic (DA) neurons in the ventral tegmental area (VTA) is widely accepted. In contrast, the lateral habenular complex (LHb), which is known as the center of the anti‐reward system, directly and indirectly inhibits DA neurons in the VTA. The VTA, however, is not a homogenous entity. Instead, it displays major functional differences between its anterior (aVTA) and posterior (pVTA) regions. It is not precisely known, whether habenular input to the aVTA, pVTA, and the newly recognized rostromedial tegmental nucleus (RMTg) are similarly or differently organized. Consequently, the present investigation addressed the connections between LHb and aVTA, pVTA, and RMTg using retrograde and anterograde tracing techniques in the rat. Our experiments disclosed strictly reciprocal and conspicuously focal interconnections between LHbM (LHbMPc/LHbMC) and PN, as well as between RLi and LHbLO. In addition, we found that LHb inputs to the aVTA are dorsoventrally ordered. Dorsal parts of the aVTA receive afferents from LHbL and LHbM, whereas ventral parts of the aVTA are preferentially targeted by the LHbM. LHb afferents to the pVTA are distinct from those to the RMTg, given that the RMTg is primarily innervated from the LHbL, whereas pVTA receives afferents from LHbM and LHbL. These data indicate the existence of two separate pathways from the LHb to the VTA, a direct and an indirect one, which may subserve distinct biological functions.
C 1s Peak of Adventitious Carbon Aligns to the Vacuum Level: Dire Consequences for Material's Bonding Assignment by Photoelectron Spectroscopy
Authors: Greczynski Grzegorz , Hultman Lars
Published: March 2017

The C 1s signal from ubiquitous carbon contamination on samples forming during air exposure, so called adventitious carbon (AdC) layers, is the most common binding energy (BE) reference in X‐ray photoelectron spectroscopy studies. We demonstrate here, by using a series of transition‐metal nitride films with different AdC coverage, that the BE of the C 1s peak
varies by as much as 1.44 eV. This is a factor of 10 more than the typical resolvable difference between two chemical states of the same element, which makes BE referencing against the C 1s peak highly unreliable. Surprisingly, we find that C 1s shifts correlate to changes in sample work function
, such that the sum
is constant at 289.50±0.15 eV, irrespective of materials system and air exposure time, indicating vacuum level alignment. This discovery allows for significantly better accuracy of chemical state determination than offered by the conventional methods. Our findings are not specific to nitrides and likely apply to all systems in which charge transfer at the AdC/substrate interface is negligible.
Assessment of oral cytological features in smokers and nonsmokers after application of toluidine blue
Authors: Sharbatdaran Majid , Abbaszadeh Hamid , Siadati Sepideh , Ranaee Mohammad , Hajian‐Tilaki Karimollah , Rajabi‐Moghaddam Mahdieh
Published: March 2017

Introduction

Smoking is the most important etiologic factor of oral cancer. Exfoliative cytology is the best method for early detection of oral cancer. Toluidine blue staining is used for detection of oral premalignant and malignant lesions. The aim of this study was to enhance the accuracy of oral exfoliative cytology in evaluating dysplastic features using toluidine blue staining.

Methods and Materials

This clinical trials study was performed on 60 male smokers and nonsmokers without clinically oral lesion. Oral exfoliative cytological smears were prepared before and after application of toluidine blue and stained with Papanicolaou and evaluated under light microscope. Cytological features such as cellular clumping nuclear‐to‐cytoplasmic ratio, cellular and nuclear pleomorphism, micronuclei, binucleation, presence of bacterial colonies, and keratin flakes were assessed and compared before and after application of toluidine blue.

Results

Results showed that cellular clumping and micronuclei were significantly decreased after application of toluidine blue and conversely cellular and nuclear pleomorphisms were significantly increased. Frequency of micronuclei and binucleation were greater in smokers than nonsmokers which were insignificant. Cellular and nuclear pleomorphisms were significantly higher in smokers than nonsmokers after application of toluidine blue.

Conclusion

Toluidine blue improved cellular, nuclear, and structural features of oral cytological smears and filtered false‐positive or false‐negative results. Thus, application of toluidine blue in combination with oral exfoliative cytology for early detection of oral cancer is recommended. Diagn. Cytopathol. 2017;45:513–519. © 2017 Wiley Periodicals, Inc.
Nickel(II) N‐Heterocyclic Carbene Complexes: Versatile Catalysts for C–C, C–S and C–N Coupling Reactions
Authors: Junquera Lourdes Benítez , Fernández Francys E. , Puerta M. Carmen , Valerga Pedro
Published: March 2017

A variety of NiII complexes with a wide range of electronic and steric properties, bearing picolylimidazolidene ligands (a–g) and Cp (Cp = η5‐C5H5; 2a–f) or Cp* (Cp* = η5‐C5Me5; 3a, c, g) groups, have been synthesised and characterised by using NMR spectroscopy and single‐crystal X‐ray crystallography. The complexes have been used as precatalysts for a wide range of catalytic transformations, which most likely involve a Ni0/NiII catalytic cycle. In particular, the new well‐defined 2a, 2c, 3a and 3c complexes have demonstrated great efficiency and versatility towards Suzuki–Miyaura coupling reactions, hydroamination of activated olefins and C–S cross‐coupling reactions of aryl halides and thiols under mild conditions.
Heterogeneous Photoredox Catalysis: Reactions, Materials, and Reaction Engineering
Authors: Bloh Jonathan Z. , Marschall Roland
Published: March 2017

This microreview briefly summarizes recent developments in heterogeneous photoredox catalysis, with a special focus on materials, reactors, and reaction design to optimize yields. New areas such as the integration of enzymatic processes are also presented, together with an extended overview of materials, reactors, and engineering.
Locked nucleic acid (LNA): Based single‐stranded oligonucleotides are not genotoxic
Authors: Guérard Melanie , Andreas Zeller , Erich Koller , Christine Marchand , Martina Müller B. , Christian Weile , Franz Schuler , Thomas Singer , Yann Tessier
Published: March 2017

Over the last decade, single stranded oligonucleotides (ON) have gained increased attention as a new drug modality. Because the assessment of genotoxicity risk during early development of pharmaceuticals is essential, we evaluated the potential of locked nucleic acids (LNA)‐ONs to induce DNA damage in L5178Y tk+/− cells both with the mouse lymphoma assay (MLA) and the micronucleus test (MNT). Further, the MLA was performed to assess gene and chromosome mutation over 3 and 24h (± metabolic activation). In addition, the MNT was performed to assess, in addition, a potential aneugenic liability. None of the experiments demonstrated a genotoxic effect for the five tested LNA‐ONs. We further show data from four proprietary LNA‐ONs tested in standard genotoxicity assays in vitro and partially in vivo, which were all negative. In addition, cellular and nuclear uptake of LNA‐ONs in L5178Y tk+/− cells was demonstrated. Based on the results presented here as well as in the literature about other representatives of this class, we consider LNA‐ONs as generally not DNA reactive and question whether genotoxicity testing of this class of ONs should be required. This is in line with recent recommendation made by the OSWG that extensively assessed the genotoxicity of oligonucleotides. Environ. Mol. Mutagen. 58:112–121, 2017. © 2017 Wiley Periodicals, Inc.
Design of hysteretic dampers with optimal ductility for the transverse seismic control of cable‐stayed bridges
Authors: Camara Alfredo , Cristantielli Roberto , Astiz Miguel A. , Málaga‐Chuquitaype Christian
Published: March 2017

Cable‐stayed bridges require a careful consideration of the lateral force exerted by the deck on the towers under strong earthquakes. This work explores the seismic response of cable‐stayed bridges with yielding metallic dampers composed of triangular plates that connect the deck with the supports in the transverse direction. A design method based on an equivalent single‐degree of freedom approximation is proposed. This is proved valid for conventional cable‐stayed bridges with 200‐ and 400‐m main spans, but not 600 m. The height of the plates is chosen to (1) achieve a yielding capacity that limits the maximum force transmitted from the deck to the towers, and to (2) control the hysteretic energy that the dampers dissipate by defining their design ductility. In order to select the optimal ductility and the damper configuration, a multi‐objective response factor that accounts for the energy dissipation, peak damper displacement and low‐cycle fatigue is introduced. The design method is applied to cable‐stayed bridges with different spans and deck–support connections. The results show that the dissipation by plastic deformation in the dampers prevents significant damage in the towers of the short‐to‐medium‐span bridges under the extreme seismic actions. However, the transverse response of the towers in the bridge with a 600‐m main span is less sensitive to the dampers. Copyright © 2017 John Wiley & Sons, Ltd.
Acetylcholinesterase inhibitors for electroconvulsive therapy‐induced cognitive side effects: a systematic review
Authors: Henstra Marieke J. , Jansma Elise P. , van der Velde Nathalie , Swart Eleonora L. , Stek Max L. , Rhebergen Didi
Published: March 2017

Objective

Electroconvulsive therapy (ECT) is an effective treatment for severe late‐life depression; however, ECT‐induced cognitive side effects frequently occur. The cholinergic system is thought to play an important role in the pathogenesis. We systematically reviewed the evidence for acetylcholinesterase inhibitors (Ache‐I) to prevent or reduce ECT‐induced cognitive side effects.

Methods

A systematic search was performed in Pubmed, EMBASE, PsychINFO, and the Cochrane database to identify clinical trials investigating the effect of Ache‐I on ECT‐induced cognitive side effects. Key search terms included all synonyms for ECT and Ache‐I. Risk of bias assessment was conducted by using the Cochrane Collaboration's tool.

Results

Five clinical trials were eligible for inclusion. All studies focused on cognitive functioning as primary endpoint, but assessment of cognitive functioning varied widely in time point of assessment and in cognitive tests that were used. There was also great variety in study medication, route and time of administration and dosages, duration of drug administration, and ECT techniques. Finally, only two out of five studies were considered at low risk of bias. Despite the aforementioned shortcomings, without exception, all studies demonstrated significantly better cognitive performance in individuals treated with Ache‐I.

Conclusions

Despite large heterogeneity in studies, Ache‐I appear to have beneficial effects on ECT‐induced cognitive side effects, supporting an association with the cholinergic system in ECT‐induced cognitive impairment. Methodological sound studies controlling for putative confounders are warranted. Copyright © 2017 John Wiley & Sons, Ltd.
Recollection and familiarity in aging individuals: Gaining insight into relationships with medial temporal lobe structural integrity
Authors: Schoemaker Dorothee , Mascret Charlotte , Collins D. Louis , Yu Elsa , Gauthier Serge , Pruessner Jens C.
Published: March 2017

Dual‐process theories posit that two separate processes are involved in recognition, namely recollection and familiarity. Studies investigating the neuroanatomical substrates of these two processes have frequently revealed that, while recollection is functionally linked with the hippocampus, familiarity appears to be associated with perirhinal and/or entorhinal cortices integrity. Interestingly these regions are known to be sensitive to normal and neuropathological aging processes. The objective of this study was to examine the effects of aging on recollection and familiarity performance, as well as to investigate associations with the rate of false alarms. In older individuals, we further aimed to explore relationships between these recognition variables and structural integrity of the hippocampus and the entorhinal and perirhinal cortices. Younger (N = 56) and older (N = 59) adults were tested on a computerized recollection and familiarity task. In a separate session, older adults (N = 56) underwent a structural MRI. Hippocampal, entorhinal and perihinal cortices volumes were automatically segmented and then manually corrected to ensure validity of the volumetric assessment. Regional volumes were normalized for total intracranial volume. While the overall recognition performance did not significantly differ across groups, our results reveal a decrease in recollection, together with an increase in familiarity in older adults. The increase reliance on familiarity was significantly and positively associated with the rate of false alarms. In the older adult sample, significant positive associations were found between recollection estimates and normalized hippocampal volumes. The normalized total hippocampal volume accounted for 25% of the variance in recollection performance. No correlation was found between any recognition variables and perirhinal or entorhinal cortices volumes. Overall, our results suggest that the age‐related impairment in recollection is linked with reduced hippocampal structural integrity.
Stereocontrolled Synthesis of Spiroketals: An Engine for Chemical and Biological Discovery
Authors: Verano Alyssa L. , Tan Derek S.
Published: March 2017

Spiroketals are key structural motifs found in diverse natural products with compelling biological activities. However, stereocontrolled synthetic access to spiroketals, independent of their inherent thermodynamic preferences, is a classical challenge in organic synthesis that has limited in‐depth biological exploration of this intriguing class. Herein, we review our laboratory's efforts to advance the glycal epoxide approach to the stereocontrolled synthesis of spiroketals via kinetically controlled spirocyclization reactions. This work has provided new synthetic methodologies with applications in both diversity‐ and target‐oriented synthesis, fundamental insights into structure and reactivity, and efficient access to spiroketal libraries and natural products for biological evaluation.
Maternal circulating levels of transforming growth factor‐β superfamily and its soluble receptors in hypertensive disorders of pregnancy
Authors: Xu Yan‐ting , Shen Min‐hong , Jin Ai‐ying , Li Hong , Zhu Rui
Published: March 2017

Objective

To assess circulating levels of transforming growth factor (TGF)‐β superfamily members and their soluble receptors in hypertensive disorders of pregnancy, and to investigate associations with clinical manifestations.

Methods

A retrospective study was conducted using data for women admitted to a center in China for delivery between May 2011 and April 2013. Women with severe pre‐eclampsia, mild pre‐eclampsia, and gestational hypertension were included, along with a control group. Serum levels of activin A, inhibin A, TGF‐β1, soluble endoglin (sEng), and soluble betaglycan (sBG) were measured.

Results

Women with severe pre‐eclampsia (n = 17) had higher mean levels of activin A (23.5±2.1 μg/L), inhibin A (1.7±0.2 μg/L), sEng (32.1±3.2 μg/L), and sBG (84.1±9.4 μg/L) than did normotensive controls (n = 18), women with gestational hypertension (n = 15), and those with mild pre‐eclampsia (n = 14; all P<0.05). Women with early‐onset pre‐eclampsia (n = 13) had higher levels of these serum markers than did preterm normotensive controls (n = 8; all P<0.001). Women with severe or early‐onset pre‐eclampsia had the lowest TGF‐β1 levels. Activin A, inhibin A, sEng, and sBG levels were positively correlated with mean arterial pressure and proteinuria (all P<0.01).

Conclusion

Pre‐eclampsia is associated with an imbalance of members of the TGF‐β superfamily and their soluble receptors, which might contribute to the development of pre‐eclampsia and help to predict onset and severity.
Coping with Climate Change in a densely Populated Delta: A Paradigm Shift in Flood and Water Management in The Netherlands
Authors: Ritzema H.P. , Van Loon‐Steensma J.M.
Published: March 2017

The expected effects of climate change and economic and population growth have motivated the Netherlands government to reformulate its policies on flood protection and water management. Flood protection and drainage are needed to make this low‐lying country habitable and suitable for agriculture and other land uses: more than 65% of the Netherlands is protected by dykes against flooding. The likely impacts of climate change in combination with socio‐economic developments call for proactive and innovative plans. The new policies and standards are based on an innovative approach: instead of focusing only on prevention, the new standards take into account both the probability of flooding as well as the potential impacts and risks of flooding, for example the individual risk of being hit by a flood. Based on these new standards, conservation, adaptation and mitigation actions are used to create a multi‐layer safety approach that focuses on the water management system as well as spatial planning. Examples are presented of changes in perspectives and how flood protection, water management and spatial planning are being combined. These examples can be a basis for further adaptation measures in both the Netherlands as well as in other low‐lying countries worldwide. Copyright © 2017 John Wiley & Sons, Ltd.
Evaluation of climatic variables as yield‐limiting factors for maize in Kansas
Authors: Ye Qing , Lin Xiaomao , Adee Eric , Min Doohong , Assefa Mulisa Yared , O'Brien Dan , Ciampitti Ignacio A.
Published: March 2017

Kansas is situated from the lower Missouri Basin to the high plains lying along the eastern slope of the Rockies so that distinct climates across the state make crop production systems vulnerable to changes in climate. Based on climatic indices such as growing degree‐day (GDD), extreme degree‐day (EDD), and precipitation (P), this study assessed the sensitivity of maize (Zea mays L.) yield to a changing climate for seven diverse cropping areas from 1981 to 2013 across Kansas. Our results indicated that maize yield increased by 2.4 and 3.4% per annum 100 GDD increase under non‐irrigated (i.e. rainfed) and irrigated environments, respectively. Maize yield positive response to changes in GDD during the pre‐silking period was more significantly pronounced for irrigated environments than rainfed sites. Rainfed yields showed a significantly negative response to EDD (−3.0% per +10 EDD) compared with irrigated environments (−1.2% per +10 EDD). This EDD negative effect was more pronounced during post‐silking growth as compared with the pre‐silking period for both irrigated and non‐irrigated conditions. Yield sensitivity to a unit change of P (mm) was less than the sensitivity to a unit change of GDD (in °C days) and EDD (in °C days) indices. Nonetheless, maize productivity has a positive response to post‐silking P with a greater yield gain at rainfed sites compared with irrigated sites. Irrigation could partially mitigate the effect of extreme heat on maize yield potential. Because the frequency of extreme temperatures and P are predicted to increase in Kansas and the Great Plains region, this study might provide guidelines to farmers, crop consultants, and agronomists to manage maize production thereby providing the ability to mitigate or adapt to climate change impacts.
Employing an urban meteorological network to monitor air temperature conditions in the ‘local climate zones’ of Szeged, Hungary
Authors: Skarbit Nóra , Stewart Iain D. , Unger János , Gál Tamás
Published: March 2017

We analyse the average annual and seasonal air temperature conditions in the ‘local climate zones’ (LCZs) of Szeged, Hungary. The basis of our analysis is a 1‐year dataset from 2014 to 2015 for a 20‐station urban meteorological network. The network and its corresponding LCZ classes put temperature studies in Szeged into a new spatial framework to assess local climate and urban heat island (UHI) conditions. The stations were installed at locally representative sites using a Geographic Information System (GIS) method based on the standard surface parameters of the LCZ classification. The network was purposely designed to monitor thermal differences among LCZ classes in Szeged. We provide detailed site metadata for each of the monitoring stations used in the analysis. Our results show that the densely built‐up LCZ classes have higher annual and monthly mean and minimum air temperatures than structurally open and more vegetated classes, with nocturnal differences of >4 °C observed under calm, clear skies. Among select temperature indices measured in the urban LCZ classes, frost days, cooling degree‐days, and tropical nights differ markedly from the background rural LCZ classes. This difference suggests that local climatologies exist within Szeged, and that these have implications for thermal comfort, urban energy use, and urban agriculture. Finally, the evaluation of heating and cooling rates in Szeged shows an important role for LCZs in UHI analysis.
Facilitating the performance of qNMR analysis using automated quantification and results verification
Authors: Monakhova Yulia B. , Diehl Bernd W. K.
Published: March 2017

Quantitative nuclear magnetic resonance (qNMR) is considered as a powerful tool for measuring the absolute amount of small molecules in complex mixtures. However, verification of the accuracy of such quantification is not a trivial task. In particular, preprocessing and integration steps are challenging and potentially erroneous. A script was developed in Matlab environment to automate qNMR analysis. Verification of the results is based on two evolving integration profiles. The analysis of binary mixtures of internal standards as well as pharmaceutical products has shown that all common artifacts (phase and baseline distortion, impurities) can be easily recognized in routine qNMR experiments. In the absence of distortion, deviation between automatically (mean value of several integrals) and manually calculated values was generally below 0.1%. The routine is independent of multiplet pattern, solvent, spectrometer, nuclei type and pulse sequence used. In general, the usage of the developed script can facilitate and verify results of routine qNMR analysis in an automatic manner. Copyright © 2017 John Wiley & Sons, Ltd.
Accuracy of fully automated, quantitative, volumetric measurement of the amount of fibroglandular breast tissue using MRI: correlation with anthropomorphic breast phantoms
Authors: Wengert Georg J. , Pinker Katja , Helbich Thomas H. , Vogl Wolf‐Dieter , Spijker Sylvia M. , Bickel Hubert , Polanec Stephan H. , Baltzer Pascal A.
Published: March 2017

To demonstrate the accuracy of fully automated, quantitative, volumetric measurement of the amount of fibroglandular breast tissue (FGT), using MRI, and to investigate the impact of different MRI sequences using anthropomorphic breast phantoms as the ground truth.

In this study, 10 anthropomorphic breast phantoms that consisted of different known fractions of adipose and protein tissue, which closely resembled normal breast parenchyma, were developed. Anthropomorphic breast phantoms were imaged with a 1.5 T unit (Siemens, Avantofit) using an 18‐channel breast coil. The sequence protocol consisted of an isotropic Dixon sequence (Di), an anisotropic Dixon sequence (Da), and T1 3D FLASH sequences with and without fat saturation (T1). Fully automated, quantitative, volumetric measurement of FGT for all anthropomorphic phantoms and sequences was performed and correlated with the amounts of fatty and protein components in the phantoms as the ground truth.

Fully automated, quantitative, volumetric measurements of FGT with MRI for all sequences ranged from 5.86 to 61.05% (mean 33.36%). The isotropic Dixon sequence yielded the highest accuracy (median 0.51%–0.78%) and precision (median range 0.19%) compared with anisotropic Dixon (median 1.92%–2.09%; median range 0.55%) and T1‐weighted sequences (median 2.54%–2.46%; median range 0.82%). All sequences yielded good correlation with the FGT content of the anthropomorphic phantoms. The best correlation of FGT measurements was identified for Dixon sequences (Di, R2 = 0.999; Da, R2 = 0.998) compared with conventional T1‐weighted sequences (R2 = 0.971).

MRI yields accurate, fully automated, quantitative, volumetric measurements of FGT, an increasingly important and sensitive imaging biomarker for breast cancer risk. Compared with conventional T1 sequences, Dixon‐type sequences show the highest correlation and reproducibility for automated, quantitative, volumetric FGT measurements using anthropomorphic breast phantoms as the ground truth.
Biologically sustainable rubber resin and rubber‐filler promoter: a precursor study
Authors: Manoharan Partheban , Naskar Kinsuk
Published: March 2017

Enthused by the ever growing demand for sustainable and green based materials in responding to applications based on macromolecules, an attempt was made in seeking a bio‐resin (Terpene). Herein, we report the functionalization of bio‐resin with natural rubber (NR) to produce new sustainable and greener functional polymer. Bio‐resin functionalized NR was prepared by melt mixing using di(2‐tert butyl peroxy isopropyl) benzene initiator. Structure elucidation of the bio‐resin functionalized NR was established by proton nuclear magnetic resonance and Fourier transform infrared spectroscopy, respectively. Bio‐resin functionalized NR facilitates the augmented interaction with highly dispersible silica. Amended state of highly dispersible silica dispersion has been achieved in the absence of toxic process oil, expensive silane coupling agent and conventionally used zinc oxide. Remarkable improvement in overall properties corroborated with various meticulous characterization including nanoindentation, rheological, physico‐mechanical and small angle X‐ray scattering using Becauge model, etc. The dynamic mechanical properties of the greener polymer demonstrated low rolling resistance coupled with high traction. More decisively, the macromolecule system toned up sparingly in the presence of the bio‐resin. Our contribution facilitates a novel avenue to develop sustainable high‐performance elastomeric macromolecule. Copyright © 2017 John Wiley & Sons, Ltd.
Epoxy composites with ceramic core–shell fillers for thermal management in electrical devices
Authors: Rybak Andrzej , Gaska Karolina , Kapusta Czeslaw , Toche François , Salles Vincent
Published: March 2017

In this work, a novel core–shell material has been manufactured in order to enhance the thermal conductivity of epoxy‐based composites. The polymer derived ceramics technique has been used to produce fillers whose core is composed of a standard material – silica, and whose outer layer consists of a boron nitride or silicon nitride shell. The synthesized filler was characterized by infrared spectroscopy, X‐ray diffraction, and scanning electron microscopy coupled with an energy dispersive spectroscopy analysis. The successful formation of core–shell structure was proven. Composite samples based on an epoxy resin filled with 31 vol% of synthetized core–shell filler have been investigated in order to determine the effective thermal conductivity of the modified system. The resulting core–shell composite samples exhibited improvements in thermal conductivity of almost 30% in relation to standard systems, making them a promising material for heat management applications. Additionally, the temperature dependence of the thermal conductivity was investigated over a broad temperature range indicating that the thermal behavior of the composite with incorporated core–shell filler is stable. This stability is a crucial factor when considering the potential of using this technology in applications such as electronics and power systems. Copyright © 2017 John Wiley & Sons, Ltd.
High throughput quantification of apolipoproteins A‐I and B‐100 by isotope dilution MS targeting fast trypsin releasable peptides without reduction and alkylation
Authors: Parks Bryan A , Schieltz David M , Andrews Michael L , Gardner Michael S , Rees Jon C , Toth Christopher A , Jones Jeffrey I , McWilliams Lisa G , Kuklenyik Zsuzsanna , Pirkle James L , Barr John R
Published: March 2017

Purpose

Apolipoprotein A‐I (ApoA‐I) and apolipoprotein B‐100 (ApoB‐100) are amphipathic proteins that are strong predictors of cardiovascular disease risk. The traceable calibration of apolipoprotein assays is a persistent challenge, especially for ApoB‐100, which cannot be solubilized in purified form.

Experimental design

A simultaneous quantitation method for ApoA‐I and ApoB‐100 was developed using tryptic digestion without predigestion reduction and alkylation, followed by LC separation coupled with isotope dilution MS analysis. The accuracy of the method was assured by selecting structurally exposed signature peptides, optimal choice of detergent, protein:enzyme ratio, and incubation time. Peptide calibrators were value assigned by isobaric tagging isotope dilution MS amino acid analysis.

Results

The method reproducibility was validated in technical repeats of three serum samples, giving 2–3% intraday CVs (N = 5) and <7% interday CVs (N = 21). The repeated analysis of interlaboratory harmonization standards showed −1% difference for ApoA‐I and −12% for ApoB‐100 relative to the assigned value. The applicability of the method was demonstrated by repeated analysis of 24 patient samples with a wide range of total cholesterol and triglyceride levels.

Conclusions and clinical relevance

The method is applicable for simultaneous analysis of ApoA‐I and ApoB‐100 in patient samples, and for characterization of serum pool calibrators for other analytical platforms.
The Effect of Coating Process and Additives on EVA Coated Tyvek® for Gas Sterilizable Medical Packaging Applications
Authors: Kwon Hyok , Kim Dowan , Lee Kang‐dae , Seo Jongchul , Lee Hwal‐Jong
Published: March 2017

Tyvek®, as an ethylene oxide (EtO) gas sterile medical packaging material with a high‐gas permeation and serving as an excellent microbial barrier, must be coated with heat‐sealable adhesives to thermally seal various plastic packaging trays or films. Tyvek® sheet coated with heat‐sealable adhesives must have both porous structure and good sealing strength to various substrates. In this study, an acid pre‐coating method was distinctively introduced to minimize reactions between the blowing agent and acid during mixing, to resultantly generate ethyl vinyl acetate (EVA) layers with porous structure on Tyvek® sheets. To determine the feasibility of applying the as‐prepared coated Tyvek® as a sterile medical packaging material, we investigated the properties of the coating solution and coated Tyvek® as a function of process and additive composition. Finally, EtO gas sterilization tests were performed, and property changes in the coated Tyvek® were investigated. Properties of the coated Tyvek® were strongly dependent on the pre‐coating process and the composition of various additives. Pre‐coating with citric acid led to less of a reaction between citric acid and ammonium carbonate as a blowing agent during mixing and resulted in both good seal strength and air permeation for the coated Tyvek® sheets. The coated Tyvek® sheets, composed of a water‐based EVA emulsion solution with various additives, were not affected by the EtO sterilization process and yielded good resistance to humidity, EtO gas and vacuum cycles. The coated Tyvek® sheets prepared by applying an acid pre‐coating may be a promising candidate for gas sterilizable medical device packaging materials. Copyright © 2017 John Wiley & Sons, Ltd.
Effective and Eco‐friendly Lubrication Protocol Using Nanodiamonds in a Dry Regime for Conveyor Systems in the Beverage Industry
Authors: Torres‐Sanchez Carmen , Balodimos Nikolaos
Published: March 2017

Conveyor belts play an important role in the production process. Their efficiency and lifespan are strongly influenced by the use of appropriate lubrication systems, cleaning procedures and operator handling. Overuse of chemicals and detergents can result in belt degradation and corrosion. Excessive friction between the packages and the load bearing surface of the conveyors (e.g. belts or chains) can wear the packaging, delay start‐ups and increase product waste. A suitably lubricated conveyor system increases longevity and promotes operational reliability. However, this has traditionally been achieved by using large amounts of water and harsh detergents. The solution proposed in this study comprises the formulation of a nanodiamond particle‐loaded food‐grade lubricating oil, a nanolubricant, for use on packaging transport and conveyor systems. Deployed in a ‘dry’ regime, the nanolubricant is hydrophobic; its viscosity is suitable to be sprayed, and a long shelf life ensures stable dispersions. Tribological performance on high‐density polyethylene conveyor belts transporting aseptic carton packs was studied. When using the nanolubricant, wearing on the packages was reduced 60% compared with no lubricating conditions and 17% lower than current commercial solutions used for benchmarking purposes. The preparation of the nanolubricant using sonication technology presents efficiencies and carbon footprint reductions derived from lower energy consumption in the production process. This nanolubricant is an environmentally friendly solution for the maintenance of machinery for packaging and transporting and a novel mechanism to curb product returns due to aesthetic and structural damages on the packaging. Copyright © 2017 John Wiley & Sons, Ltd.
Large‐Scale Roll‐to‐Roll Patterned Oxygen Indicators for Modified Atmosphere Packages
Authors: Saarinen Jarkko J. , Remonen Tommi , Tobjörk Daniel , Aarnio Harri , Bollström Roger , Österbacka Ronald , Toivakka Martti
Published: March 2017

We demonstrate roll‐to‐roll fabrication of ultraviolet A light‐activated colorimetric oxygen indicators on paper and plastic substrates. Such large‐scale, cost‐effective and non‐toxic oxygen indicator and production method can find applications as a very low‐cost leakage indicator for modified atmosphere packages by printing the material directly or gluing the pre‐printed indicator label inside the lid. The introduction of leakage indicators onto all modified atmosphere packages could result in improved food safety and reduced food spoilage. Copyright © 2017 John Wiley & Sons, Ltd.
Fault‐tolerant control for Markovian jump systems with general uncertain transition rates against simultaneous actuator and sensor faults
Authors: Li Xiaohang , Zhu Fanglai
Published: March 2017

This paper investigates the problems of simultaneous estimations of actuator faults and sensor faults, as well as fault‐tolerant control schemes for a class of Markovian jump systems with general uncertain transition rates. In a general uncertain transition rate matrix model, transition rate may be completely unknown, or one can only acquire its estimated value, which makes the design much more challenging. First, the original system is transformed into a descriptor one by extending the sensor faults to be parts of state vector. Then, a robust stochastic adaptive observer is designed for the descriptor system with the actuator fault being adjusted by an adaptive law. On the basis of the estimated states as well as estimated actuator and sensor faults, a fault‐tolerant control strategy is proposed to make the resulting closed‐loop system stable in the presence of the actuator fault. Sufficient existence conditions of the observer and controller are derived in terms of linear matrix inequalities. Finally, three practical examples are given to validate the high efficiency of our proposed method. Copyright © 2017 John Wiley & Sons, Ltd.
Society Reschooling
Authors: Street Brian V.
Published: March 2017

This essay offers a commentary on how the relationship between language and literacy practices in and out of school has been conceptualized. It draws upon two new books in the field. Shirley Brice Heath's new book, Words at Work and Play: Three Decades in Family and Community Life, which makes use of rich ethnographic accounts of children's educational and literacy development across three generations, following her initial study of families in Ways With Words, argues that “everyday, informal learning that all engage in will link with and complement the more formal directions” (p. 169). In The Great Literacy Debate, an edited book from the U.K., the authors argue that the government's National Literacy Strategy there did not succeed, a failure which they claim was to be explained in terms of problems with how literacy was defined. A key issue for the authors, in both the U.S. and the U.K., is their criticism of formal educational approaches to literacy and the recognition that school needs to take account of social factors outside of school in helping pupils acquire the reading and writing skills required by schooling. This essay draws out the notion of two “fields” in the approach to literacy as a way of characterizing the issues raised: the field in which “literacy” is defined and performed in education and the field of New Literacy Studies, with its emphasis on social practice in a wider context than schooling. In an attempt to broaden the international focus of the consideration of the possible link between these two fields—how literacy in everyday life can be linked with literacy in educational contexts—the article then extends to a consideration of a program in which ethnographic perspectives have been applied to help teachers build on adult learners’ prior literacies. The project developed by Rogers and Street (2011) is labeled Learning Empowerment Through Training in Ethnographic Research (LETTER) and has been applied in a number of international contexts, such as India, Ethiopia, and Uganda. The paper concludes by pointing to a direction in which a literacy strategy might build on actual practice of the kind described, taking account of the theoretical and pedagogical principles developed in the books and programs reviewed here.
The Role of Inference Making and Other Language Skills in the Development of Narrative Listening Comprehension in 4–6‐Year‐Old Children
Authors: Lepola Janne , Lynch Julie , Laakkonen Eero , Silvén Maarit , Niemi Pekka
Published: March 2017

In this two‐year longitudinal study, we sought to examine the developmental relationships among early narrative listening comprehension and language skills (i.e., vocabulary knowledge, sentence memory, and phonological awareness) and the roles of these factors in predicting narrative listening comprehension at the age of 6 years. We also sought to examine the role of inference‐making skills as longitudinal and concurrent predictors of other language skills and listening comprehension from the age of 4 to 6 years. One hundred thirty Finnish‐speaking children participated in the study. A theoretical model of the developmental relationships among the variables was proposed and the associations were analyzed by means of path analysis. Results showed that inference skills, assessed through picture‐book viewing, made a significant and unique contribution to variation in later narrative listening comprehension. Inference skills also played an indirect role in narrative listening comprehension by making a significant contribution to vocabulary knowledge even after controlling for earlier vocabulary knowledge and sentence memory. Although vocabulary knowledge and sentence memory were related to concurrent narrative listening comprehension, they did not predict later listening comprehension over and above the autoregressor. The results are discussed in terms of the predictive validity and diagnostic sensitivity of inference skills assessments in listening comprehension. Implications for research and theory are also discussed.
Mechanisms of Tolerance Induction by Hematopoietic Chimerism: The Immune Perspective
Authors: Yolcu Esma S. , Shirwan Haval , Askenasy Nadir
Published: March 2017

Hematopoietic chimerism is one of the effective approaches to induce tolerance to donor-derived tissue and organ grafts without administration of life-long immunosuppressive therapy. Although experimental efforts to develop such regimens have been ongoing for decades, substantial cumulative toxicity of combined hematopoietic and tissue transplants precludes wide clinical implementation. Tolerance is an active immunological process that includes both peripheral and central mechanisms of mutual education of coresident donor and host immune systems. The major stages include sequential suppression of early alloreactivity, establishment of hematopoietic chimerism and suppressor cells that sustain the state of tolerance, with significant mechanistic and temporal overlap along the tolerization process. Efforts to devise less toxic transplant strategies by reduction of preparatory conditioning focus on modulation rather than deletion of residual host immunity and early reinstitution of regulatory subsets at the central and peripheral levels.