bluuebunny/crossref_metadata_2025 huggingface dataset:
Processes and facies relationships in a Lower(?) Devonian rocky shoreline depositional environment, East Lime Creek Conglomerate, south‐western Colorado, USA
Authors: Evans James E. , Holm‐Denoma Christopher S.
Published: February 2018

Rocky shorelines are relatively common features along modern coastlines, but few have been recognized in the geological record. The hard substrates of rocky shorelines telescope the width of offshore marine environments, thus the diagnostic deposits observed in such settings today have a low preservation potential due to small accommodation space and high‐energy conditions. This study recognized previously overlooked, laterally extensive Lower(?) Devonian rocky shoreline deposits in the San Juan Mountains of south‐western Colorado. The newly defined lithostratigraphic unit, the East Lime Creek Conglomerate (ELCC), is 0–23 m thick, unconformably overlying Proterozoic crystalline rocks and unconformably overlain by the Upper Devonian Ignacio Formation and/or Elbert Formation. The unit mostly consists of clast‐supported cobble‐boulder conglomerate with rounded quartzite clasts up to 1.4 m in length interbedded with thin sandstone layers and lenses. Sandstones in the ELCC are distinguished from unconformably overlying Upper Devonian sedimentary rocks because they have sericite cements. Most importantly, there are buttressing relationships between the ELCC and underlying Proterozoic crystalline rocks interpreted as palaeo‐sea cliffs, palaeo‐wave‐cut platforms and palaeo‐tombolos. A proposed rocky shoreline facies model includes headlands with upper shoreface‐beachface tabular cobble‐boulder gravels sourced from rock fall talus, nearshore subaqueous debris‐flow deposits and intervening pocket beaches with imbricated, stratified pebble‐cobble gravel sheets. Palaeocurrent data (n = 338) from clast long‐axis orientations, imbrication and cross‐bedding indicate south‐to‐north transport roughly onshore‐offshore to a coastline consisting of alternating rocky headlands and pocket beaches. This Lower(?) Devonian unit documents a previously unrecognized episode in the geological history of south‐western Colorado.
An analytical framework for estimating aquatic species density from environmental DNA
Authors: Chambert Thierry , Pilliod David S. , Goldberg Caren S. , Doi Hideyuki , Takahara Teruhiko
Published: February 2018

Environmental DNA (eDNA) analysis of water samples is on the brink of becoming a standard monitoring method for aquatic species. This method has improved detection rates over conventional survey methods and thus has demonstrated effectiveness for estimation of site occupancy and species distribution. The frontier of eDNA applications, however, is to infer species density. Building upon previous studies, we present and assess a modeling approach that aims at inferring animal density from eDNA. The modeling combines eDNA and animal count data from a subset of sites to estimate species density (and associated uncertainties) at other sites where only eDNA data are available. As a proof of concept, we first perform a cross‐validation study using experimental data on carp in mesocosms. In these data, fish densities are known without error, which allows us to test the performance of the method with known data. We then evaluate the model using field data from a study on a stream salamander species to assess the potential of this method to work in natural settings, where density can never be known with absolute certainty. Two alternative distributions (Normal and Negative Binomial) to model variability in eDNA concentration data are assessed. Assessment based on the proof of concept data (carp) revealed that the Negative Binomial model provided much more accurate estimates than the model based on a Normal distribution, likely because eDNA data tend to be overdispersed. Greater imprecision was found when we applied the method to the field data, but the Negative Binomial model still provided useful density estimates. We call for further model development in this direction, as well as further research targeted at sampling design optimization. It will be important to assess these approaches on a broad range of study systems.
Population genetic structure, introgression, and hybridization in the genus Rhizophora along the Brazilian coast
Authors: Francisco Patrícia M. , Mori Gustavo M. , Alves Fábio M. , Tambarussi Evandro V. , de Souza Anete P.
Published: February 2018

Mangrove plants comprise plants with similar ecological features that have enabled them to adapt to life between the sea and the land. Within a geographic region, different mangrove species share not only similar adaptations but also similar genetic structure patterns. Along the eastern coast of South America, there is a subdivision between the populations north and south of the continent's northeastern extremity. Here, we aimed to test for this north‐south genetic structure in Rhizophora mangle, a dominant mangrove plant in the Western Hemisphere. Additionally, we aimed to study the relationships between R. mangle, R. racemosa, and R. × harrisonii and to test for evidence of hybridization and introgression. Our results confirmed the north‐south genetic structure pattern in R. mangle and revealed a less abrupt genetic break in the northern population than those observed in Avicennia species, another dominant and widespread mangrove genus in the Western Hemisphere. These results are consistent with the role of oceanic currents influencing sea‐dispersed plants and differences between Avicennia and Rhizophora propagules in longevity and establishment time. We also observed that introgression and hybridization are relevant biological processes in the northeastern coast of South America and that they are likely asymmetric toward R. mangle, suggesting that adaptation might be a process maintaining this hybrid zone.
A generalist and a specialist herbivore are differentially affected by inbreeding and trichomes in Mimulus guttatus
Authors: Haber Ariela I. , Rivera Sustache Julia , Carr David E.
Published: February 2018

Inbreeding in plants is well known to affect plant–herbivore interactions, but these effects can depend on herbivore host breadth. If the phenotypic effects of inbreeding are analogous to those of environmental stress, the plant stress hypothesis predicts that generalist herbivores will perform better on inbred relative to outbred plants because inbreeding is expected to lower chemical defenses. The plant vigor hypothesis predicts that specialist herbivores will perform better on outbred relative to inbred plants because specialists are more tolerant of plant defenses and benefit from the higher nutritional quality of outbred plants. However, these plant defense theories do not account for structural defenses. Using a factorial design, we examined effects of inbreeding and trichome density in Mimulus guttatus on performance of the generalist, Helicoverpa zea, and the specialist, Junonia coenia. We also examined preferences of each herbivore for leaf disks and olfactory cues from inbred vs. outbred plants. The generalist H. zea developed most efficiently on inbred plants. The specialist J. coenia exhibited the greatest mass gain and pupal mass and developed fastest on outbred plants. Trichomes negatively affected performance of both species. Helicoverpa zea did not exhibit strong preferences for inbred vs. outbred plants, but J. coenia consistently preferred outbred plants. Our results support predictions on the effects of inbreeding on herbivore performance, but trichomes reduced performance of both herbivores. We conclude that the ability of the plant stress and plant vigor hypotheses to predict inbreeding effects on plant–herbivore interactions may depend on which plant traits are affected by inbreeding.
Arginase‐1 is neither constitutively expressed in nor required for myeloid‐derived suppressor cell‐mediated inhibition of T‐cell proliferation
Authors: Bian Zhen , Abdelaal Ahmed Mansour , Shi Lei , Liang Hongwei , Xiong Lanqiao , Kidder Koby , Venkataramani Mahathi , Culpepper Courtney , Zen Ke , Liu Yuan
Published: February 2018

Although previous reports suggest that tumor‐induced myeloid‐derived suppressor cells (MDSC) inhibit T cells by L‐arginine depletion through arginase‐1 activity, we herein show that arginase‐1 is neither inherently expressed in MDSC nor required for MDSC‐mediated inhibition. Employing Percoll density gradients, large expansions of MDSC in the bone marrow of tumor‐bearing mice were isolated and demonstrated potent inhibition in T‐cell proliferation activated by TCR‐ligation, Concanavalin A, PMA plus ionomycin, or IL‐2. Despite demonstrating characteristic immunosuppressive capacity, these MDSC exhibit no arginase‐1 expression and/or exert their inhibitory effects independent of arginase‐1 activity. However, arginase‐1 expression in MDSC can be induced by exposure to TCR‐activated T cells or their culture medium, but not T cells activated by other means or growing tumor cells. Further investigation reveals multiple cytokines secreted by TCR‐activated T cells as orchestrating two signaling‐relay axes, IL‐6‐to‐IL‐4 and GM‐CSF/IL‐4‐to‐IL‐10, leading to arginase‐1 expression in MDSC. Specifically, IL‐6 signaling increases IL‐4R, enabling IL‐4 to induce arginase‐1 expression; similarly, GM‐CSF in concert with IL‐4 induces IL‐10R, allowing IL‐10‐mediated induction. Surprisingly, our study indicates that induction of arginase‐1 expression is not conducive to the critical MDSC‐mediated inhibition toward T cells, which is rather dependent on direct cell contacts undiminished by PD‐L1 blockade or SIRPα deficiency.
Enhancement of Luminescence Efficiencies by Thermal Rearrangement from ortho‐ to meta‐Carborane in Bis‐Carborane‐Substituted Acenes
Authors: Naito Hirofumi , Uemura Kyoya , Morisaki Yasuhiro , Tanaka Kazuo , Chujo Yoshiki
Published: February 2018

In a previous study we synthesized a series of bis‐o‐carborane‐modified acenes and revealed various unique luminescence properties, such as highly efficient solid‐state emission and luminochromism. Here we report further enhancement of the luminescence efficiencies of bis‐o‐carborane‐modified acenes by thermally induced structural rearrangement from ortho‐ to meta‐carborane. We found that the thermal rearrangement of the anthracene derivative 1 occurred close to the melting point and gave luminescent products. From a detailed investigation of the product obtained from 1, the transformation of the molecular structure was proven by X‐ray crystallography. In addition, the analytical data indicated that rearrangement caused by heating at 300 °C occurred at only one of the two o‐carborane units. In accord with the results of theoretical investigations of the transition states of 1 by quantum chemical calculations, we propose that the thermal rearrangement could proceed because of a low activation energy in the first rearrangement step due to the presence of the anthracene. On the basis of optical measurements, enhancements of not only luminescence efficiencies but also aggregation‐induced emission were observed. Furthermore, we have demonstrated that this strategy for enhancing emission properties is applicable ot the corresponding tetracene derivative, resulting in a deep‐red luminescent dye.
Policy impact on volatility dynamics in commodity futures markets: Evidence from China
Authors: Zhang Yongmin , Ding Shusheng , Scheffel Eric
Published: February 2018

Chinese financial markets play an ever more pertinent role in the global economic context and are therefore increasingly relevant for stabilizing the economy. In this paper, we scrutinize the impact of a series of new policies on stock index futures trading, which have recently been enacted by the Chinese government. We pay particular attention to the way in which these have influenced commodity market volatilities and how their impact on liquidity has affected volatility more generally. Our results reveal a novel interaction between the new government policy and market forces which drive volatilities in commodity markets.
Metallogenesis of the Late Palaeozoic Axi–Tawuerbieke Au–Pb–Zn district in the Tulasu Basin, Western Tianshan, China: Constraints from geological characteristics and isotope geochemistry
Authors: Peng Yi‐Wei , Gu Xue‐Xiang , Cheng Wen‐Bin , Zhao Xiao‐Bo , Wang Guan‐Nan , Lu Liang‐Tao , Han Jian‐Min
Published: February 2018

The Tulasu Basin is an important epithermal gold ore cluster situated in the Boluokenu Polymetallic Belt, Western Tianshan, China. The Axi Au, Tabei Pb–Zn, and Tawuerbieke Au deposits in this basin represent different types of epithermal mineralization. These are products of the same tectonic‐magmatic‐hydrothermal event, related to the southward subduction of the North Tianshan Ocean beneath the Yili‐Central Tianshan Plate during the Late Devonian to Early Carboniferous. The spatial relationships, preservation levels, and evolution of the three deposits are still debated. Hence, systematic geological field investigations, ore microscopy, and isotopic analyses were carried out on these three deposits. The S–Pb–C–H–O isotopic compositions indicate that the ore‐forming components were derived from the volcanic‐subvolcanic rocks, as well as from circulating meteoric waters. The occurrence of adularia, silicified platy carbonates, and quartz characterized by crustiform/colloform/colloidal textures at Axi indicate that boiling was the main precipitation mechanism for the Au mineralization. The Pb–Zn ores from Tabei are characterized by abundant banded coarse‐grained quartz crystals with dog tooth and comb textures, suggesting that the sulphides precipitated slowly due to conductive cooling. The Tawuerbieke Au deposit is characterized by pervasive silicification and phyllic alteration accompanying veinlet and disseminated ore, which formed via metasomatic water–rock interaction. According to the ore textures, intrusion sizes, and mineral assemblages, it can be inferred that all three deposits experienced different extents of erosion (Axi < Tabei < Tawuerbieke) and that there is exploration potential for concealed porphyry Cu–Au mineralization. Exploration should focus on deep targets beneath the Tawuerbieke Au deposit.
Study on the potential of cultivated land quality improvement based on a geological detector
Authors: Yuan Xuefeng , Shao Yajing , Wei Xindong , Hou Rui , Ying Yue , Zhao Yonghua
Published: February 2018

The restrictive factors of cultivated land are key to the improvement of cultivated land quality, scientific implementation of the land consolidation projects, and the efficiency of remediation. On the basis of the provincial plots of cultivated land quality in Shaanxi Province, this paper analysed the improvement potential of cultivated land quality from the perspective of restrictive factors. First, the potential exponential model was used to determine the distribution of various combinations of restrictive factors at the provincial scale. Second, a geological detector was used to determine the influences of different combinations of restrictive factors on cultivated land quality. Finally, through the investigation of cultivated land consolidation projects that have been implemented in the study area, the improvement potential level of different combinations of restrictive factors was determined. The degree of influence of the single restrictive factor or combinations of restrictive factors on the quality of cultivated land was improved, and the difference of the quality of cultivated land in different index areas could be revealed as well. The results showed that there were 12 single‐factor restrictions and 34 double‐factor restrictions. The area under single‐factor restrictions reached 76.77% of the total land. The quality of cultivated land in the southern and central areas of Shaanxi Province was relatively good. The quality of cultivated land in the northern region was under significant influence of restrictive factors whereas that in southern and middle areas was less affected. From the perspective of improvement potential of restrictive factors, Shaanxi was relatively low with huge internal diversity, whereas the improvement potential in northern Shaanxi had huge advantage.
The conformation of bovine serum albumin adsorbed to the surface of single all‐dielectric nanoparticles following light‐induced heating
Authors: Krasilin Andrei A. , Volodina Katerina , Sukhova Arina A. , Petrov Mihail I. , Zuev Dmitry A. , Dyachuk Vyacheslav A. , Milichko Valentin A.
Published: February 2018

Interaction between nanoparticles and biomolecules leads to the formation of biocompatible or bioadverse complexes. Despite the rapid development of nanotechnologies for biology and medicine, relatively little is known about the structure of such complexes. Here, we report on the changes in conformation of a blood protein (bovine serum albumin) adsorbed on the surface of single all‐dielectric nanoparticles (silicon and germanium) following light‐induced heating to 640 K. This protein is considerably more resistant to heat when adsorbed on the nanoparticle than when in solution or in the solid state. Intriguingly, with germanium nanoparticles this heat resistance is more pronounced than with silicon. These observations will facilitate biocompatible usage of all‐dielectric nanoparticles.
Antimicrobial photodynamic inactivation is potentiated by the addition of selenocyanate: Possible involvement of selenocyanogen?
Authors: Huang Liyi , Xuan Weijun , Zadlo Andrzej , Kozinska Anna , Sarna Tadeusz , Hamblin Michael R.
Published: February 2018

We previously showed that antimicrobial photodynamic inactivation (aPDI) of Gram‐positive and Gram‐negative bacteria mediated by the phenothiazinium dye, methylene blue (MB), was potentiated by the addition of potassium thiocyanate (10 mM). The mechanism was suggested to involve a singlet oxygen‐mediated reaction with SCN to form sulfite and cyanide and then to produce sulfur trioxide radical anion. We now report that potassium selenocyanate (concentrations up to 100 mM) can also potentiate (up to 6 logs of killing) aPDI mediated by a number of different photosensitizers (PS): MB, rose bengal and 5,10,15,20‐tetrakis(4‐sulfonatophenyl)porphyrin dihydrochloride (as low as 200 nM). When a mixture of selenocyanate with these PS in solution was illuminated and then bacteria were added after the light, there was up to 6 logs of killing (Gram‐negative > Gram‐positive) but the antibacterial species decayed rapidly (by 20 minutes). Our hypothesis to explain this antibacterial activity is the formation of selenocyanogen (SeCN)2 by reaction with singlet oxygen (1O2) as shown by quenching of 1O2 by SeCN and increased photoconsumption of oxygen. The fact that lead tetraacetate reacted with SeCN (literature preparation of (SeCN)2) also produced a short‐lived antibacterial species supports this hypothesis.
The influence of mindfulness, self‐compassion, psychological flexibility, and posttraumatic stress disorder on disability and quality of life over time in war veterans
Authors: Meyer Eric C. , Frankfurt Sheila B. , Kimbrel Nathan A. , DeBeer Bryann B. , Gulliver Suzy B. , Morrisette Sandra B.
Published: February 2018

Objectives

Posttraumatic stress disorder (PTSD) strongly predicts greater disability and lower quality of life (QOL). Mindfulness‐based and other third‐wave behavior therapy interventions improve well‐being by enhancing mindfulness, self‐compassion, and psychological flexibility. We hypothesized that these mechanisms of therapeutic change would comprise a single latent factor that would predict disability and QOL after accounting for PTSD symptom severity.

Method

Iraq and Afghanistan war veterans (N = 117) completed a study of predictors of successful reintegration. Principal axis factor analysis tested whether mindfulness, self‐compassion, and psychological flexibility comprised a single latent factor. Hierarchical regression tested whether this factor predicted disability and QOL 1 year later.

Results

Mindfulness, self‐compassion, and psychological flexibility comprised a single factor that predicted disability and QOL after accounting for PTSD symptom severity. PTSD symptoms remained a significant predictor of disability but not QOL.

Conclusions

Targeting these mechanisms may help veterans achieve functional recovery, even in the presence of PTSD symptoms.
Identification and validation of a multi‐assay algorithm for cross‐sectional HIV incidence estimation in populations with subtype C infection
Authors: Laeyendecker Oliver , Konikoff Jacob , Morrison Douglas E , Brookmeyer Ronald , Wang Jing , Celum Connie , Morrison Charles S , Abdool Karim Quarraisha , Pettifor Audrey E , Eshleman Susan H
Published: February 2018

Introduction

Cross‐sectional methods can be used to estimate HIV incidence for surveillance and prevention studies. We evaluated assays and multi‐assay algorithms (MAAs) for incidence estimation in subtype C settings.

Methods

We analysed samples from individuals with subtype C infection with known duration of infection (2442 samples from 278 adults; 0.1 to 9.9 years after seroconversion). MAAs included 1‐4 of the following assays: Limiting Antigen Avidity assay (LAg‐Avidity), BioRad‐Avidity assay, CD4 cell count and viral load (VL). We evaluated 23,400 MAAs with different assays and assay cutoffs. We identified the MAA with the largest mean window period, where the upper 95% confidence interval (CI) of the shadow was <1 year. This MAA was compared to the LAg‐Avidity and BioRad‐Avidity assays alone, a widely used LAg algorithm (LAg‐Avidity <1.5 OD‐n + VL >1000 copies/mL), and two MAAs previously optimized for subtype B settings. We compared these cross‐sectional incidence estimates to observed incidence in an independent longitudinal cohort.

Results

The optimal MAA was LAg‐Avidity <2.8 OD‐n  +  BioRad‐Avidity <95% + VL >400 copies/mL. This MAA had a mean window period of 248 days (95% CI: 218, 284), a shadow of 306 days (95% CI: 255, 359), and provided the most accurate and precise incidence estimate for the independent cohort. The widely used LAg algorithm had a shorter mean window period (142 days, 95% CI: 118, 167), a longer shadow (410 days, 95% CI; 318, 491), and a less accurate and precise incidence estimate for the independent cohort.

Conclusions

An optimal MAA was identified for cross‐sectional HIV incidence in subtype C settings. The performance of this MAA is superior to a testing algorithm currently used for global HIV surveillance.
Pyrosequencing method for sensitive detection of HBV drug resistance mutations
Authors: Lee Guan‐Huei , Inoue Masafumi , Chong Roxanne Hui‐Heng , Toh Jimmy , Wee Sue Yuen , Loh Kah‐Sin , Lim Seng‐Gee
Published: February 2018

Hepatitis B (HBV) drug resistance assay is important for guiding therapy after the development of virologic breakthrough for patients receiving nucleoside/‐tide analog therapy. However, the existing genotyping tools are either costly or lack sensitivity to detect mixed genotypes, and an improved method of resistant mutation detection is needed. An assay protocol for clinical application using pyrosequencing method was developed, capable of detecting all known validated HBV polymerase gene mutations that impart resistance to lamivudine, adefovir, tenofovir, and entecavir. Sixty‐eight serum samples with known HBV resistance genotypes, previously tested with either Sanger sequencing assay or commercial line probe assay, were used for validation. Where there were discrepancies between the two methods, clonal sequencing by Sanger's method was used for confirmation. The modified pyrosequencing method accurately identified all the cloned polymerase genotypes and was able to distinguish as little as 5% of the mutant populations. This assay can be performed on serum sample with HBV DNA as low as 13.5 IU/mL. The cost per test was less than existing commercial assay. HBV drug resistance pyrosequencing assay was accurate, more sensitive and cheaper compared with the existing methods. It can detect minor populations of drug‐resistant clones earlier, before the drug resistant clones become dominant, allowing the opportunity for an earlier change of therapy.
Analysis of growth and lipid production characteristics of Chlorella vulgaris in artificially constructed consortia with symbiotic bacteria
Authors: Xue Lingui , Shang Hai , Ma Ping , Wang Xia , He Xiaoyan , Niu Junbo , Wu Juanli
Published: February 2018

The aim was to study the effect of artificially constructed consortia of microalgae‐bacterial symbionts on growth and lipid production by Chlorella vulgaris (C. vulgaris), as well as the inter‐relationship between microalgae and bacterial in a photoautotrophic system. The results showed that compared to an axenic culture of C. vulgaris, H1 co‐culture system (axenic C. vulgaris‐Stenotrophomona smaltophilia) had the strongest effect on the C. vulgaris growth. The biomass, specific growth rate and maximum productivity of C. vulgaris were increased by 21.9, 20.4, and 18%, respectively. The bacteria in co‐culture system had a significant effect on the accumulation of lipid and fatty acid components of C. vulgaris: the content of lipid was increased by 8.2–33.83%, and the components of the saturated fatty acids and oleic acids also had an obvious improvement. The results indicate that the microalgae‐bacterial co‐culture system can improve microalgal biomass and the quality of biodiesel.
Polyplex Particles Based on Comb‐Like Polyethylenimine/Poly(2‐ethyl‐2‐oxazoline) Copolymers: Relating Biological Performance with Morphology and Structure
Authors: Haladjova Emi , Halacheva Silviya , Momekova Denitsa , Moskova‐Doumanova Veselina , Topouzova‐Hristova Tanya , Mladenova Kirilka , Doumanov Jordan , Petrova Maria , Rangelov Stanislav
Published: February 2018

The present contribution is focused on feasibility of using comb‐like copolymers of polyethylenimine with poly(2‐ethyl‐2‐oxazoline) (LPEI‐comb‐PEtOx) with varying grafting densities and degrees of polymerization of PEI and PEtOx to deliver DNA molecules into cells. The copolymers form small and well‐defined particles at elevated temperatures, which are used as platforms for binding and condensing DNA. The electrostatic interactions between particles and DNA result in formation of sub‐100 nm polyplex particles of narrow size distribution and different morphology and structure. The investigated gene delivery systems exhibit transfection efficiency dependent on the copolymer chain topology, shape of the polyplex particles, and internalization pathway. Flow cytometry shows enhanced transfection efficiency of the polyplexes with elongated and ellipsoidal morphology. The preliminary biocompatibility study on a panel of human cell lines shows that pure copolymers and polyplexes thereof are practically devoid of cytotoxicity.
A Fast, Reversible, and Robust Gradient Nanocomposite Hydrogel Actuator with Water‐Promoted Thermal Response
Authors: Tan Yun , Wang Di , Xu Huaxiu , Yang Yang , An Wenli , Yu Lina , Xiao Zhixin , Xu Shimei
Published: February 2018

Poly(N‐isopropylacrylamide)/Laponite (PNIPAM/Laponite) gradient nanocomposite hydrogel actuators are developed as temperature‐controlled actuators with excellent performance using a facile electrophoresis method. The actuators exhibit a rapid (20 s response time) and reversible response, as well as large deformation (bending angle of 231°), which is due to the graded forces generated by the thermo‐induced anisotropic shrinkage and extension of the gradient hydrogels. A good linear relationship is observed between the maximum bending angles and the corresponding temperatures for the actuators with fixed sizes. Moreover, the gradient hydrogel with high water content achieved larger actuation angles and shorter response time than the one with low water content, showing an interesting water‐promoted effect. Meanwhile, different types of actuators are designed to suit for more specific scenarios, and may be used for various applications, such as biosensing, artificial organization, and transportation of targeted objects.
Animal models of l‐dopa‐induced dyskinesia in Parkinson's disease
Authors: Cenci M. Angela , Crossman Alan R.
Published: February 2018

Understanding the biological mechanisms of l‐dopa‐induced motor complications is dependent on our ability to investigate these phenomena in animal models of Parkinson's disease. The most common motor complications consist in wearing‐off fluctuations and abnormal involuntary movements appearing when plasma levels of l‐dopa are high, commonly referred to as peak‐dose l‐dopa‐induced dyskinesia. Parkinsonian models exhibiting these features have been well‐characterized in both rodent and nonhuman primate species. The first animal models of peak‐dose l‐dopa‐induced dyskinesia were produced in monkeys lesioned with N‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) and treated chronically with l‐dopa to elicit choreic movements and dystonic postures. Seminal studies were performed in these models using both metabolic mapping and electrophysiological techniques, providing fundamental pathophysiological insights that have stood the test of time. A decade later, it was shown possible to reproduce peak‐dose l‐dopa‐induced dyskinesia in rats and mice rendered parkinsonian with nigrostriatal 6‐hydroxydopamine lesions. When treated with l‐dopa, these animals exhibit abnormal involuntary movements having both hyperkinetic and dystonic components. These models have enabled molecular‐ and cellular‐level investigations into the mechanisms of l‐dopa‐induced dyskinesia. A flourishing literature using genetically engineered mice is now unraveling the role of specific genes and neural circuits in the development of l‐dopa‐induced motor complications. Both non‐human primate and rodent models of peak‐dose l‐dopa‐induced dyskinesia have excellent construct validity and provide valuable tools for discovering therapeutic targets and evaluating potential treatments. © 2018 International Parkinson and Movement Disorder Society
In vivo hyperpolarization transfer in a clinical MRI scanner
Authors: von Morze Cornelius , Reed Galen D. , Larson Peder E. , Mammoli Daniele , Chen Albert P. , Tropp James , Van Criekinge Mark , Ohliger Michael A. , Kurhanewicz John , Vigneron Daniel B. , Merritt Matthew E.
Published: February 2018

Purpose

The purpose of this study was to investigate the feasibility of in vivo 13C‐>1H hyperpolarization transfer, which has significant potential advantages for detecting the distribution and metabolism of hyperpolarized 13C probes in a clinical MRI scanner.

Methods

A standalone pulsed 13C RF transmit channel was developed for operation in conjunction with the standard 1H channel of a clinical 3T MRI scanner. Pulse sequences for 13C power calibration and polarization transfer were programmed on the external hardware and integrated with a customized water‐suppressed 1H MRS acquisition running in parallel on the scanner. The newly developed RF system was tested in both phantom and in vivo polarization transfer experiments in 1JCH‐coupled systems: phantom experiments in thermally polarized and hyperpolarized [2‐13C]glycerol, and 1H detection of [2‐13C]lactate generated from hyperpolarized [2‐13C]pyruvate in rat liver in vivo.

Results

Operation of the custom pulsed 13C RF channel resulted in effective 13C‐>1H hyperpolarization transfer, as confirmed by the characteristic antiphase appearance of 1H‐detected, 1JCH‐coupled doublets. In conjunction with a pulse sequence providing 190‐fold water suppression in vivo, 1H detection of hyperpolarized [2‐13C]lactate generated in vivo was achieved in a rat liver slice.

Conclusion

The results show clear feasibility for effective 13C‐>1H hyperpolarization transfer in a clinical MRI scanner with customized heteronuclear RF system.
Dark period transcriptomic and metabolic profiling of two diverse Eutrema salsugineum accessions
Authors: Yin Jie , Gosney Michael J. , Dilkes Brian P. , Mickelbart Michael V.
Published: February 2018

Eutrema salsugineum is a model species for the study of plant adaptation to abiotic stresses. Two accessions of E. salsugineum, Shandong (SH) and Yukon (YK), exhibit contrasting morphology and biotic and abiotic stress tolerance. Transcriptome profiling and metabolic profiling from tissue samples collected during the dark period were used to investigate the molecular and metabolic bases of these contrasting phenotypes. RNA sequencing identified 17,888 expressed genes, of which 157 were not in the published reference genome, and 65 of which were detected for the first time. Differential expression was detected for only 31 genes. The RNA sequencing data contained 14,808 single nucleotide polymorphisms (SNPs) in transcripts, 3,925 of which are newly identified. Among the differentially expressed genes, there were no obvious candidates for the physiological or morphological differences between SH and YK. Metabolic profiling indicated that YK accumulates free fatty acids and long‐chain fatty acid derivatives as compared to SH, whereas sugars are more abundant in SH. Metabolite levels suggest that carbohydrate and respiratory metabolism, including starch degradation, is more active during the first half of the dark period in SH. These metabolic differences may explain the greater biomass accumulation in YK over SH. The accumulation of 56% of the identified metabolites was lower in F1 hybrids than the mid‐parent averages and the accumulation of 17% of the metabolites in F1 plants transgressed the level in both parents. Concentrations of several metabolites in F1 hybrids agree with previous studies and suggest a role for primary metabolism in heterosis. The improved annotation of the E. salsugineum genome and newly identified high‐quality SNPs will permit accelerated studies using the standing variation in this species to elucidate the mechanisms of its diverse adaptations to the environment.
High‐fidelity detection of crop biomass quantitative trait loci from low‐cost imaging in the field
Authors: Banan Darshi , Paul Rachel E. , Feldman Max J. , Holmes Mark W. , Schlake Hannah , Baxter Ivan , Jiang Hui , Leakey Andrew D.B.
Published: February 2018

Field‐based, rapid, and nondestructive techniques for assessing plant productivity are needed to accelerate the discovery of genotype‐to‐phenotype relationships in next‐generation biomass grass crops. The use of hemispherical imaging and light attenuation modeling was evaluated against destructive harvest measures with respect to their ability to accurately capture phenotypic and genotypic relationships in a field‐grown grass crop. Plant area index (PAI) estimated from below‐canopy hemispherical images, as well as a suite of thirteen traits assessed by manual destructive harvests, were measured in a Setaria recombinant inbred line mapping population segregating for aboveground productivity and architecture. A significant correlation was observed between PAI and biomass production across the population at maturity (r2 = .60), as well as for select diverse genotypes sampled repeatedly over the growing season (r2 = .79). Twenty‐seven quantitative trait loci (QTL) were detected for manually collected traits associated with biomass production. Of these, twenty‐one were found in four clusters of colocalized QTL. Analysis of image‐based estimates of PAI successfully identified all four QTL hot spots for biomass production. QTL for PAI had greater overlap with those detected for traits associated with biomass production than with those for plant architecture and biomass partitioning. Hemispherical imaging is an affordable and scalable method, which demonstrates how high‐throughput phenotyping can identify QTL related to biomass production of field trials in place of destructive harvests that are labor, time, and material intensive.
An acylation‐Finkelstein approach to radioiodination of bioactives: The role of amide group anchimeric assistance
Authors: Fjellaksel Richard , Dugalic Damir , Demissie Taye B. , Riss Patrick J. , Hjelstuen Ole‐Kristian , Sundset Rune , Hansen Jørn H.
Published: February 2018

Herein, we report a straightforward sequential acylation‐Finkelstein approach to achieve iodination of amine containing bioactives. The utility was demonstrated by successful radiolabelling with 123I in high radiochemical yield. Moreover, microwave‐assisted Finkelstein reaction can be employed to enhance conversion and reaction rates to obtain the desired iodides. The method is of interest for radioiodination of amine‐containing bioactives. The mechanistic details of the iodination process were studied by kinetics and density functional theory calculations, which revealed the mechanistic complexity of the reaction involving amide group anchimeric assistance. We disclose a number of fundamental aspects of amide group anchimeric assistance in substitution reactions.
Cancer survivors' understanding of the cause and cure of their illness: Religious and secular appraisals
Authors: Carney Lauren M. , Park Crystal L.
Published: February 2018

Objective

Little is known about survivors' understanding of the cause of their cancer and of their recovery, nor how these ways of understanding relate to their well‐being. No study has examined both secular and religious appraisals of the same event. The current study aimed to examine both religious (God) and secular (self) appraisals of both the cause (attributions) and course/cure of cancer in relation to multiple aspects of adjustment.

Methods

Data were obtained from a sample of cancer survivors at Time 1 (n = 250) and 1 year later (Time 2, n = 167).

Results

Cancer survivors endorsed higher appraisals relating to course/cure of their cancer than those relating to cause, and they endorsed both secular and religious appraisals. Appraisals of the cause and course/cure of cancer were differentially related to adjustment, such that self‐attributions of cause and God‐attributions of cause were related to negative aspects of adjustment (eg, negative affect and pessimism), while appraisals of self and God's control over the course/cure were related to positive aspects of adjustment (eg, perceived positive life and health changes since cancer). Religiosity did not moderate most of relationships between religious appraisals and adjustment outcomes.

Conclusions

Secular and religious appraisals of cancer are not mutually exclusive, and religious appraisals are associated with adjustment regardless of survivors' religiosity. Appraisals relating to cause and course/cure have differential relationships with well‐being. Addressing cancer survivors' appraisals—religious or nonreligious—in a therapeutic setting may be beneficial regardless of their reported religiosity.
High‐Frequency Flexible Graphene Field‐Effect Transistors with Short Gate Length of 50 nm and Record Extrinsic Cut‐Off Frequency
Authors: Yu Cui , He Zezhao , Song Xubo , Liu Qingbin , Gao Libo , Yao Bing , Han Tingting , Gao Xuedong , Lv Yuanjie , Feng Zhihong , Cai Shujun
Published: February 2018

Flexible graphene field effect transistors (GFETs) are fabricated on a polyimide (PI) substrate by an improved self‐aligned fabrication procedure. Short gate length of 50 nm is achieved. Ohmic contact resistance is depressed. The prepared GFET shows comparable intrinsic cut‐off frequency and maximum oscillation frequency of 116 and 110 GHz, respectively. The high frequency of flexible GFET demonstrated here paves the way for applications which require high flexibility and radio frequency operations.
Characterization of Athabasca lean oil sands and mixed surficial materials: Comparison of capillary electrophoresis/low‐resolution mass spectrometry and high‐resolution mass spectrometry
Authors: MacLennan Matthew S. , Peru Kerry M. , Swyngedouw Chris , Fleming Ian , Chen David D.Y. , Headley John V.
Published: February 2018

Rationale

Oil sands mining in Alberta, Canada, requires removal and stockpiling of considerable volumes of near‐surface overburden material. This overburden includes lean oil sands (LOS) which cannot be processed economically but contain sparingly soluble petroleum hydrocarbons and naphthenic acids, which can leach into environmental waters. In order to measure and track the leaching of dissolved constituents and distinguish industrially derived organics from naturally occurring organics in local waters, practical methods were developed for characterizing multiple sources of contaminated water leakage.

Methods

Capillary electrophoresis/positive‐ion electrospray ionization low‐resolution time‐of‐flight mass spectrometry (CE/LRMS), high‐resolution negative‐ion electrospray ionization Orbitrap mass spectrometry (HRMS) and conventional gas chromatography/flame ionization detection (GC/FID) were used to characterize porewater samples collected from within Athabasca LOS and mixed surficial materials. GC/FID was used to measure total petroleum hydrocarbon and HRMS was used to measure total naphthenic acid fraction components (NAFCs). HRMS and CE/LRMS were used to characterize samples according to source.

Results

The amounts of total petroleum hydrocarbon in each sample as measured by GC/FID ranged from 0.1 to 15.1 mg/L while the amounts of NAFCs as measured by HRMS ranged from 5.3 to 82.3 mg/L. Factors analysis (FA) on HRMS data visually demonstrated clustering according to sample source and was correlated to molecular formula. LRMS coupled to capillary electrophoresis separation (CE/LRMS) provides important information on NAFC isomers by adding analyte migration time data to m/z and peak intensity.

Conclusions

Differences in measured amounts of total petroleum hydrocarbons by GC/FID and NAFCs by HRMS indicate that the two methods provide complementary information about the nature of dissolved organic species in a soil or water leachate samples. NAFC molecule class OxSy is a possible tracer for LOS seepage. CE/LRMS provides complementary information and is a feasible and practical option for source evaluation of NAFCs in water.
Mechanical Properties and Deformation Behavior of Nano/ultrafine Fe–18Cr–8Ni Austenitic Steel Processed by Low Temperature Rolling and Annealing Treatment
Authors: Liu Jia , Deng Xiang‐Tao , Huang Long , Wang Zhao‐Dong , Misra Raja Devesh Kumar
Published: February 2018

In the present study, the method of phase reversion process is adopted to obtain nanograined/ultrafine‐grained (NG/UFG) structure in 18Cr–8Ni austenitic stainless steel. Severe cold deformation (86% reduction) at room temperature and (64%, 86% reduction) at −50 °C is carried out, followed by annealing in the conditions of 650 °C–50 min and 700 °C–15 min. The influence of different cold rolling and annealing conditions on the microstructure and mechanical properties of stainless steel is studied. The decrease of rolling temperature and the increase of reduction lead to the volume fraction of strain‐induced martensite increase. Lath‐type martensite, dislocation cell‐type martensite, and untransformed austenite in 64% reduction (at −50 °C) and mainly dislocation cell‐type structure in 86% reduction (at room temperature and −50 °C) are observed. Increasing reduction or rolling temperature promotes the cold‐rolled α texture of strain‐induced martensite to the stable orientations. The grain size obtained is in the range of 0.4–0.89 μm, with yield strength in the range of 684–1017 MPa and high ductility of 23–54%. Deformation behavior shows that the amount of twins and stacking faults at 5 mm distance from the fracture is higher than the fracture.
The projective stable category of a coherent scheme
Authors: Estrada Sergio , Gillespie James
Published: February 2018

We define the projective stable category of a coherent scheme. It is the homotopy category of an abelian model structure on the category of unbounded chain complexes of quasi-coherent sheaves. We study the cofibrant objects of this model structure, which are certain complexes of flat quasi-coherent sheaves satisfying a special acyclicity condition.
Italian Psychological Literature
Authors: Gasquet J. R.
Published: February 2018

Professor Verga has collected the statistics for all the asylums in continental Italy (excluding, therefore, Sardinia and Sicily), taken on the night of December 31, 1874. There were then 170·79 lunatics to every 100,000 inhabitants, a proportion somewhat higher than in England, Ireland, and France, but lower than in Scotland. In the province of Naples, where the ratio was lowest, it was 1 to 903; while in Lombardy, where it was highest, it was 1 to 435. In Umbria the proportion of insane persons had doubled in 15 years, and in Lombardy nearly tripled in 10 years.
Rheumatism and chronic fatigue, the two facets of post-chikungunya disease: the TELECHIK cohort study on Reunion island
Authors: Duvignaud A. , Fianu A. , Bertolotti A. , Jaubert J. , Michault A. , Poubeau P. , Fred A. , Méchain M. , Gaüzère B.-A. , Favier F. , Malvy D. , Gérardin P.
Published: February 2018

Prolonged fatigue is increasingly reported among chikungunya virus (CHIKV)-infected populations. We investigated the relationships between CHIKV exposure, long-lasting rheumatic musculoskeletal pain (LRMSP) and chronic fatigue. 1094 participants (512 CHIKV seropositive and 582 seronegative) of the TELECHIK population-based cohort were analysed considering the duration of the manifestations throughout an average 2-year follow-up. Weighted prevalence rates and prevalence ratios for LRMSP, idiopathic chronic fatigue (ICF), and chronic fatigue syndrome (CFS)-like illness, both latter syndromes adapted from Centers for Disease Control (CDC)-1994/Fukuda criteria, were compared. Population attributable fractions (PAF) were estimated to assess the contribution of CHIKV infection to each of the three phenotypes. Among 362 adult subjects who had reported either rheumatic pain or fatigue at the onset of the infection, weighted prevalence rates of LRMSP, ICF and CFS-like illness were respectively of 32.9%, 38.7% and 23.9%, and of 8.7%, 8.5% and 7.4% among initially asymptomatic peers (P < 0.01, respectively). Each of the three outcomes was highly attributable to chikungunya (PAF of 43.2%, 36.2% and 41.0%, respectively). In the sub-cohort of CHIKV-infected subjects, LRMSP, ICF and CFS-like illness, which overlapped in 70%, accounted for 53% of the chronic manifestations. In addition to rheumatic disease, chronic fatigue could be considered in caring for patients with chronic chikungunya disease.
Spontaneous regression of severe aortic coarctation in trisomy 18
Authors: Matsumura Shun , Masutani Satoshi , Senzaki Hideaki
Published: February 2018

Spontaneous regression of severe aortic coarctation with ductus dependency has not been reported. We experienced a case of trisomy 18 with spontaneous regression of severe aortic coarctation complicated by ventricular septal defect and patent ductus arteriosus. The aortic isthmus diameter was 1.2 mm at birth. After 5 months, it increased to 4.5 mm, and the shape of the isthmus was fully normalised.