bluuebunny/crossref_metadata_2025 huggingface dataset:
Metabolic elicitors ofPseudomonas fluorescensN 21.4 elicit flavonoid metabolism in blackberry fruit
Authors: Martin‐Rivilla Helena , Garcia‐Villaraco Ana , Ramos‐Solano Beatriz , Gutierrez‐Manero Francisco J , Lucas José A
Published: July 2020

Background

The beneficial rhizobacterium,Pseudomonas fluorescensN 21.4, and its metabolic elicitors were inoculated in commercial cultivars of blackberry plants (Rubuscv. Loch Ness). Phenolic compounds present in red and black fruit and the expression of structural marker genes of the phenylpropanoid pathway during fruit ripening were studied.

Results

An inverse relationship between gene expression and accumulation of metabolites was seen, except for theRuDFRgene, which had a direct correlation with cyanidin 3‐O‐glucoside synthesis, increasing its content 1.3 times whenRuDFR was overexpressed in the red fruit of plants inoculated with the metabolic elicitors ofP. fluorescensN 21.4, compared with red fruit of plants inoculated with N 21.4. TheRuCHSgene also had a fundamental role in the accumulation of metabolites. Both rhizobacterium and metabolic elicitors triggered the flavonoid metabolism, enhancing the catechin and epicatechin content between 1.1 and 1.6 times in the case of red fruit and between 1.1 and 1.8 times in the case of black fruit. Both treatments also boosted the anthocyanin, quercetin, and kaempferol derivative content, highlighting the effects of metabolic elicitors in red fruit and the effects of live rhizobacterium in black fruit.

Conclusion

The metabolic elicitors' capacity to modulate gene expression and to increase secondary metabolites content was demonstrated. This work therefore suggests that they are effective, affordable, easily manageable, and ecofriendly plant inoculants that complement, or are alternatives to, beneficial rhizobacteria. © 2020 Society of Chemical Industry
Fluoride absorption, transportation and tolerance mechanism in Camellia sinensis, and its bioavailability and health risk assessment: a systematic review
Authors: Peng Chuan‐yi , Xu Xue‐feng , Ren Yin‐feng , Niu Hui‐liang , Yang Yun‐qiu , Hou Ru‐yan , Wan Xiao‐chun , Cai Hui‐mei
Published: July 2020

Tea is the one of the most popular non‐alcoholic caffeinated beverages in the world. Tea is produced from the tea plant (Camellia sinensis (L.) O. Kuntze), which is known to accumulate fluoride. This article systematically analyzes the literature concerning fluoride absorption, transportation and fluoride tolerance mechanisms in tea plants. Fluoride bioavailability and exposure levels in tea infusions are also reviewed. The circulation of fluoride within the tea plantation ecosystems is in a positive equilibrium, with greater amounts of fluoride introduced to tea orchards than removed. Water extractable fluoride and magnesium chloride (MgCl2) extractable fluoride in plantation soil are the main sources of absorption by tea plant root via active trans‐membrane transport and anion channels. Most fluoride is readily transported through the xylem as F−/F–Al complexes to leaf cell walls and vacuole. The findings indicate that tea plants employ cell wall accumulation, vacuole compartmentalization, and F–Al complexes to co‐detoxify fluoride and aluminum, a possible tolerance mechanism through which tea tolerates higher levels of fluoride than most plants. Furthermore, dietary and endogenous factors influence fluoride bioavailability and should be considered when exposure levels of fluoride in commercially available dried tea leaves are interpreted. The relevant current challenges and future perspectives are also discussed. © 2020 Society of Chemical Industry
Effect of production system and inhibitory potential of aroma volatiles on polyphenol oxidase and peroxidase activity in tomatoes
Authors: Lee Jisun HJ , Kasote Deepak M , Jayaprakasha Guddadarangavvanahally K , Avila Carlos A , Crosby Kevin M , Patil Bhimanagouda S
Published: July 2020

BACKGROUND

Polyphenol oxidase (PPO) and peroxidase (POD) are key enzymes associated with shelf life and defense responses. Thus, the activity of PPO and POD enzymes is usually assessed to check the quality of food samples and to understand the physiological responses of plants to different stresses. However, the outcomes of PPO and POD activity assessment studies are highly dependent on assay conditions. Hence, in this study, we initially optimized PPO and POD extraction and high‐throughput 96‐well plates‐based enzymatic activity assessment methods to evaluate the inhibitory potential of tomato volatile compounds. Later, we explored the effects of net‐house and open‐field growing on the PPO and POD activity in tomato fruits of eight cultivars.

RESULTS

We found 150 mM of catechol and pH 7.0 were the optimal conditions for the maximum activity for the PPO assay. Conversely, 24 mM guaiacol with 12 mM H2O2 and pH 6.0 was the best condition for the POD assay. Thermal inactivation studies confirmed that tomato POD is more resistant to heat than PPO. We found that the production systems had a considerable genotype‐specific impact on tomato PPO and POD activity. Moreover, amongst the volatiles that were studied, β‐damascenone and d‐limonene showed 50% PPO inhibition at 40 and 80 mM, respectively.

CONCLUSION

The results of this study can be used to improve the shelf‐life of fresh tomato fruit and its products. The findings also underscore the significance of PPO and POD enzymes as physiological trait markers in the tomato crop and fruit quality improvement programs. © 2020 Society of Chemical Industry
Accelerating the development of artificial biocrusts using covers for restoration of degraded land in dryland ecosystems
Authors: Zhao Yang , Wang Nan , Zhang Zhishan , Pan Yanxia , Jia Rongliang
Published: July 2020

Recent research has revealed the potential for using cyanobacteria inoculation to promote biocrusts on sandy drylands. There is global interest in using this approach to combat land degradation. Nevertheless, in order to use this biotechnology on a large scale, researchers must explore technologies that are simple and efficient to implement. To achieve this aim, we tested the effects of different covers to control dust and stabilize sand surfaces measures—that is, nonwoven fabric, dust‐proof net, and sun‐shading net—on colonization and development of artificial cyanobacteria crusts on the southeast edge of the Tengger Desert in Northern China. After 80 days, cyanobacteria crusts occurred in all inoculated soils. The best results occurred when using fresh cyanobacteria were covered with two‐layer nonwoven fabric and one‐layer sun‐shading net; this treatment resulted in 50.0% biocrust cover, 2.88 mm biocrust thickness, 19.21 μg cm2 chlorophyll a concentration, 79.05 μg cm2 total carbohydrate content, and 10.00 m s−1 threshold friction velocity, which is significantly higher than sand (3.70 m s−1). The results suggest that covering with nets can accelerate development of artificial cyanobacteria crusts, because covers improve micro‐environments and remove barriers limiting biocrust colonization. This study describes a potential approach to reconstruct or recover biocrusts, and to restore degraded land in dryland ecosystems.
Basal resource quality and energy sources in three habitats of a lowland river ecosystem
Authors: McInerney Paul J. , Holt Galen , Lester Rebecca E. , Thompson Ross M. , Robson Barbara , Ryder Darren S. , Bond Nick R. , Baldwin Darren S. , Gawne Ben , Petrie Rochelle
Published: July 2020

Understanding energy flow through ecosystems and among sub‐habitats is critical for understanding patterns of biodiversity and ecosystem function. It can also be of considerable applied interest in situations where managing for connectivity among habitats is important for restoring degraded ecosystems. Here, we describe patterns of basal resource quality and identify primary basal energy sources in three habitats—river channels, anabranches and wetlands—of a lowland river floodplain in the Murray River catchment, Australia during a period of disconnected surface flow. We used a combination of stable isotope and fatty acid analyses to determine which basal resources were assimilated by the backswimmer Anisops thienemanni and the Eastern mosquitofish Gambusia holbrooki and assessed food quality across the three habitats. Seston was a primary basal resource for both animals in all three habitats, but was of higher quality within floodplain habitats than in the river channel. Although floodplain seston contained higher concentrations of essential fatty acids, fatty acid profiles of animals from different habitats remained similar. Our research suggests that inundation of floodplains and subsequent reconnection to the river could be valuable to afford riverine animals the opportunity to access high quality resources, but highlights a need to quantitatively assess the transfer of essential fatty acids between trophic levels to determine how much riverine animals are in fact limited by poorer quality food resources. We demonstrate the importance of estimating the quality of organic matter fluxes into food webs, and the potential role of targeted environmental flows to re‐establish high quality energy pathways in riverine ecosystems.
Senate bill would authorize grants to expand rural telemental health
Authors: Enos Gary
Published: July 2020

Residents of rural communities always have struggled to gain access to effective mental health services, and the COVID‐19 crisis has only added to the urgency of the problem. A bipartisan group of U.S. senators is responding with proposed legislation that would establish a telemental health care demonstration program targeting three key industry groups prominent in rural areas.
Existence of solutions of fractional p‐Laplacian systems with different critical Sobolev‐Hardy exponents
Authors: Nyamoradi Nemat , Kirane Mokhtar
Published: July 2020

In this paper, we investigate a fractional p‐Laplacian system with different critical Sobolev‐Hardy exponents. By variational methods and the Mountain‐Pass lemma, positive minimizers of the related best Sobolev constants and the existence of positive solutions of the system are found.
Influence of surface properties on electro‐chemical supercapacitors utilizing Callerya atropurpurea pod derived porous nanocarbons: Structure property relationship between porous structures to energy storage devices
Authors: Bhat Vinay S. , S Supriya , Jayeoye Titilope John , Rujiralai Thitima , Sirimahachai Uraiwan , Chong Kwok Feng , Hegde Gurumurthy
Published: July 2020

Surface properties always play a dominant role in the energy storage devices. Understanding the surface phenomena is the key to tune the energy storage device using biowaste based porous nano carbons. Here, Callerya atropurpurea pod derived peculiar porous nanocarbons are synthesized by pyrolysis at different temperatures without any synthetic templates approach. Elaborate analysis of surface textures on the effect of pore size, volume and specific surface area on specific capacitance and frequency response behavior of nanocarbons were studied in detail. Electrochemical characterizations establish the mutuality of porosity and microtextural properties of nanocarbons with specific capacitance. The electrochemical characterization of the novel materials as supercapacitor electrode shows a high specific capacitance of 326.54 F g−1 at 0.25 A g−1 in 1.0 M KOH. A practical symmetric supercapacitor device is fabricated with a specific capacitance of 86.38 F g−1 at 0.1 A g−1, and high energy density of 27.0 Wh kg−1. This symmetric supercapacitor also possesses outstanding capacitance retention of 92.16% for 5000 charge discharge cycles and also stability of 97.17%, after voltage holding at the maximum voltage for 100 hours. Present manuscript gives the strong evidence for structure‐property relationships so that one can tune the energy storage devices effectively.
Compatibility and toughening mechanism of poly(ethylene terephthalate)/polycarbonate blends
Authors: Liu Juan , Zhao Xiaowen , Ye Lin
Published: July 2020

Poly(ethylene terephthalate) (PET)/polycarbonate (PC) blends with methyl methacrylate‐styrene‐butadiene copolymer as compatibilizer (CP) were prepared. Compared with pure PET, the notched impact strength of the blend was improved significantly, while high tensile strength and 50%–70% optical transparency could be maintained. In particular, for the PET/70 wt% PC sample the notched impact strength sharply increased by 955% with the addition of compatibilizer. The ΔTg of the two phases of the blends decreased on blending, exhibiting partial compatibility. Below 50 wt% PC, the dispersed PC phase presented uneven dispersion with large aggregates and a clear interface, while above 50 wt% PC a reverse phase transformation occurred and the PET phase was evenly dispersed in the PC matrix with small aggregates and obvious interface transition areas. The introduction of CP promoted spherical PC particles to uniformly disperse in the matrix, and the interface transition area of the two phases became very wide. Moreover, the CP itself ran through the matrix to form a ‘quasi‐network distribution’ and the compatibility was greatly improved, thus leading to an obvious enhancement of the impact toughness of the blend. © 2020 Society of Industrial Chemistry
Spatial Atomic Layer Deposition of Aluminum Oxide as a Passivating Hole Contact for Silicon Solar Cells
Authors: Öğütman Kortan , Iqbal Nafis , Gregory Geoffrey , Li Mengjie , Haslinger Michael , Cornagliotti Emanuele , Schoenfeld Winston V. , John Joachim , Davis Kristopher O.
Published: July 2020

Herein, tunneling aluminum oxide (Al2O3) passivation layers are demonstrated to be a candidate for hole collecting, passivating contacts when coupled with a boron‐doped surface. These very thin Al2O3 films (1.5–3 nm) are deposited using spatial atomic layer deposition (ALD) on boron diffused (110–115 Ω □−1) hydrophilic surfaces operating as metal–insulator–semiconductor (MIS) contacts. The emitter saturation current density values of ≈57 fA cm−2 are achieved for the Al2O3 film thicknesses of 2 nm before metallization. At this same thickness, the contact resistivity values of 33 mΩ cm2 are obtained after metallization. Most importantly, the boron diffusion, wet chemical surface preparation, and spatial ALD of Al2O3 used to create these MIS structures are all performed with industrially relevant equipment on Cz wafers.
Plasmonic Light Trapping in Titania–Silver Dots Thin Films
Authors: Manno Daniela , Buccolieri Alessandro , Carbone Giorgio Giuseppe , Calcagnile Lucio , Serra Antonio
Published: July 2020

Metal nanoparticles (NPs) in a transparent dielectric matrix represent a very intriguing system due to the plasmonic absorption tunable in the range of visible wavelengths. Herein, the preparation and physical characterization of plasmonic titania–silver dots thin films are reported. The synthesis parameter that leads to making a TiO2 matrix in which the Ag NPs are actually incorporated is carefully analyzed and controlled. Morphological (scanning electron microscopy, transmission electron microscopy, high resolution electron microscopy), structural (selected area diffraction, X‐ray diffraction), and spectroscopic (Raman spectroscopy) characterization techniques attest that the Ag NPs are spherical and homogeneously distributed into the TiO2 dielectric matrix in the structural modification of anatase. The study of the optical properties of films concludes the work. Plasmonic resonance is analyzed according to the light scattering theory.
Auxiliary Top‐Illumination in the Kretschmann–Raether Configuration: A Theoretical Study on the Surface Plasmon Resonance Response
Authors: Falamaki Cavus , Rastegar Pashaki Elahe
Published: July 2020

A new variation of surface plasmon resonance (SPR) sensors design with Kretschmann–Raether (KR)‐type configuration is presented. Using a rotational incident angle scanning platform, the conductor nanolayer is normally irradiated with an auxiliary unpolarized light beam from the dielectric side. Both illumination sources should have a coherence length much larger than their source/Au layer optical path. Beginning with a Lorentzian‐type oscillator model, a general dispersion equation for the metal nanolayer is developed that incorporates interband transitions and polychromaticity of the top‐illumination beam. SPR curves are then predicted based on the transfer‐matrix method. Simulation results show that the top‐illumination frequency and its relative amplitude with respect to the bottom laser beam may impart significant changes to the SPR curve. It is shown that the implementation of short‐wave ultraviolet light (180 nm) may considerably improve the performance of SPR sensors in terms of the figure‐of‐merit. Larger wavelengths generally lead to performance deterioration. Based on the transverse magnetic solutions of the wave equation, a theoretical interpretation of the results is presented that confirms the strong effect of top illumination on the magnitude of the decay lengths in the conductor/dielectric and the propagation constant.
How Photoinduced Gate Screening and Leakage Currents Dynamically Change the Fermi Level in 2D Materials
Authors: Volmer Frank , Ersfeld Manfred , Rathmann Lars , Heithoff Maximilian , Kotewitz Luca , Lohmann Mark , Yang Bowen , Watanabe Kenji , Taniguchi Takashi , Bartels Ludwig , Shi Jing , Stampfer Christoph , Beschoten Bernd
Published: July 2020

An in‐depth analysis of physics in 2D materials like transition metal dichalcogenides requires the measurement of many material properties as a function of Fermi level position within the electronic band structure. This is normally done by changing the charge carrier density of the 2D material via the gate electric field effect. Herein, a comparison of gate‐dependent measurements, which are acquired under different measurement conditions, is shown to encounter significant problems due to the temporal evolution of the charging of trap states inside the dielectric layer or at its interfaces. The impact of, e.g., the gate sweep direction and the sweep rate on the overall gate dependence gets especially prominent in optical measurements due to photoexcitation of donor and acceptor states. Under such conditions, the same nominal gate voltage may lead to different gate‐induced charge carrier densities and, hence, Fermi level positions. It is demonstrated that a current flow from or even through the dielectric layer via leakage currents can significantly diminish the gate tunability in optical measurements of 2D materials.
The range of once‐reinforced random walk in one dimension
Authors: Pfaffelhuber Peter , Stiefel Jakob
Published: July 2020

We study once‐reinforced random walk on . For this model, we derive limit results on all moments of its range using Tauberian theory.
Identification and characterisation of the anti‐allergic compound from lotus root
Authors: Wakugawa Tomoharu , Nagamine Kenichi , Hiramatsu Miharu , Takeda Mayuko , Kawata Chika , Kashiwada Yoshiki , Shinohara Keiko , Sawada Eiji , Yabumoto Masami , Fujino Hiromichi , Kitamura Yoshiaki , Fukui Hiroyuki , Takeda Noriaki , Mizuguchi Hiroyuki
Published: July 2020

Aim

Histamine H1 receptor (H1R) gene is up‐regulated in the nasal mucosa of patients with pollinosis, and its expression level is strongly correlated with the severity of allergic symptoms. However, suppression of H1R mRNA to the basal level by antihistamine failed to alleviate nasal symptoms completely, and nuclear factor of activated T‐cells (NFAT) signalling was demonstrated to be the additional signalling responsible for the pathogenesis of allergic rhinitis (AR). Lotus Root (LR) has been traditionally used to improve the allergic symptoms; however, the underlying mechanism of its anti‐allergic activity is unknown. Here, we show that the LR aequeous extract suppressed ionomycin‐induced NFAT signalling‐mediated IL‐9 mRNA up‐regulation in RBL‐2H3 cells and toluene‐2,4‐diisocyanate (TDI)‐sensitised rats.

Methods

An active compound from LR was purified by aequeous extraction and ethanol precipitation followed by column chromatography, and its structure was resolved using thiol degradation followed by 1H‐NMR (nuclear magnetic resonance) and 13C‐NMR. The mRNA levels of H1R and IL‐9 were measured using real‐time reverse transcription‐polymerase chain reaction (RT‐PCR).

Results

We isolated and identified proanthocyanidin containing gallocatechin tetramer as an active compound. LR‐derived proanthocyanidin (LRPC) suppressed IL‐9 mRNA up‐regulation both in RBL‐2H3 cells and TDI‐sensitised rats. Combination therapy of LRPC with antihistamine markedly alleviated allergic symptoms.

Conclusion

Data suggest that LRPC alleviated nasal symptoms through the inhibition of IL‐9 mRNA up‐regulation, possibly through the inhibition of NFAT signalling, and that combination therapy of LRPC with antihistamine could be effective in advanced treatment for AR.
Explicit solutions of the BVPs of the theory of thermoelasticity for an elastic circle with voids and microtemperatures
Authors: Bitsadze Lamara
Published: July 2020

In the present paper, we consider an elastic circle and a plane with circular hole with voids and microtemperatures. Representations of a general solution of a system of equations for a homogeneous isotropic thermoelastic medium with voids and microtemperatures are constructed by means of the elementary (harmonic, bi‐harmonic and meta‐harmonic) functions. The Dirichlet type boundary value problems for a circle and for a plane with circular hole are solved explicitly. The obtained solutions are represented in the form of absolutely and uniformly convergent series.
Primary resonance analysis of a nonlinear flexible shaft supported by active magnetic bearings using analytical method
Authors: Hosseini S. A. A. , Yektanezhad A.
Published: July 2020

In this paper, primary resonances of a flexible rotor suspended by active magnetic bearings are investigated. The rotor has large amplitude vibrations, which leads to nonlinearities in curvature and inertia. In addition, nonlinearity characteristics of active magnetic bearings are considered. In modeling of the shaft, rotary inertia and shear deformation are neglected but gyroscopic effect is included. Here, the equations of motion and related boundary conditions are both nonlinear. To analyze the dynamical behavior of the system, the renormalization group method is directly applied to the partial differential equations of motion and boundary conditions. The effects of different parameters of the shaft and active magnetic bearings on the frequency response of the system in the neighborhood of critical speeds are investigated, and it is shown that both hardening and softening nonlinearity behaviors are possible.
Buckling of shear deformable FG‐CNTRC cylindrical shells and toroidal shell segments under mechanical loads in thermal environments
Authors: Hieu Pham Thanh , Van Tung Hoang
Published: July 2020

An analytical study on buckling of carbon nanotube reinforced composite (CNTRC) circular cylindrical shells and toroidal shell segments surrounded by elastic media, exposed to thermal environments and subjected to axial compression and combined mechanical loads is presented in this paper. Carbon nanotubes (CNTs) are reinforced into isotropic matrix through uniform and functionally graded distributions. Material properties of constituents are assumed to be temperature dependent and effective elastic moduli of CNTRC are estimated by an extended rule of mixture. Formulations are based on first order shear deformation theory taking into account interaction between the shell and surrounding medium. Two‐term solution of deflection is assumed to satisfy simply supported boundary conditions and Galerkin method is used to obtain closed‐form expressions of buckling loads. Numerical illustrations are given to analyze the effects of CNT volume fraction and distribution patterns, preexisting loads, surrounding elastic media and geometrical parameters on the stability of CNTRC shells. The proposed approach is simple and effective to evaluate buckling loads of moderately thick closed nanocomposite shells under different types of mechanical loads.
The Hopf algebra structure of the R∗-operation
Authors: Beekveldt Robert , Borinsky Michael , Herzog Franz
Published: July 2020

Abstract

We give a Hopf-algebraic formulation of the R∗-operation, which is a canonical way to render UV and IR divergent Euclidean Feynman diagrams finite. Our analysis uncovers a close connection to Brown’s Hopf algebra of motic graphs. Using this connection we are able to provide a verbose proof of the long observed ‘commutativity’ of UV and IR subtractions. We also give a new duality between UV and IR counterterms, which, entirely algebraic in nature, is formulated as an inverse relation on the group of characters of the Hopf algebra of log-divergent scaleless Feynman graphs. Many explicit examples of calculations with applications to infrared rearrangement are given.
Non-relativistic duality and $$ T\overline{T} $$ deformations
Authors: Blair Chris D.A.
Published: July 2020

Abstract

We make some observations connecting non-relativistic limits of string theory with $$ T\overline{T} $$
T

T
¯

deformations and TsT transformations.
On countably saturated linear orders and certain class of countably saturated graphs
Authors: Kostana Ziemowit
Published: July 2020

The idea of this paper is to explore the existence of canonical countably saturated models for different classes of structures. It is well-known that, under CH, there exists a unique countably saturated linear order of cardinality $$\mathfrak {c}$$
c
. We provide some examples of pairwise non-isomorphic countably saturated linear orders of cardinality $$\mathfrak {c}$$
c
, under different set-theoretic assumptions. We give a new proof of the old theorem of Harzheim, that the class of countably saturated linear orders has a uniquely determined one-element basis. From our proof it follows that this minimal linear order is a Fraïssé limit of certain Fraïssé class. In particular, it is homogeneous with respect to countable subsets. Next we prove the existence and uniqueness of the uncountable version of the random graph. This graph is isomorphic to $$(H(\omega _1),\in \cup \ni )$$

(
H

(

ω
1

)

,
∈
∪
∋
)

, where $$H(\omega _1)$$

H
(

ω
1

)

is the set of hereditarily countable sets, and two sets are connected if one of them is an element of the other. In the last section, an example of a prime countably saturated Boolean algebra is presented.
Product innovation and informal market competition in sub-Saharan Africa
Authors: Avenyo Elvis Korku , Konte Maty , Mohnen Pierre
Published: July 2020

The interaction between formal and informal businesses continues to grow in African countries. Yet, competition from informal enterprises remains one of the top three obstacles formal businesses face in sub-Saharan Africa. This paper investigates the effect of informal competition on the performance of innovative products introduced by formal firms. We combine the World Bank’s Enterprise Survey with the Innovation Follow-up Survey for five sub-Saharan African countries, and construct two indicators of informal competition, one regional (local)-specific and the other one industry-specific. We find that local informal competition has a robust negative effect on product innovation intensity of formal firms, while within industry informal competition enhances innovative sales. However, larger firms are less affected by local informal competition and actually get a boost in innovative sales from informal competition. We argue that local informal competition harms the performance of product innovation, but only for formal firms that lack strategic collaborative ‘footholds’ in the informal economy.
Double bond localization in unsaturated rhamnolipid precursors 3-(3-hydroxyalkanoyloxy)alkanoic acids by liquid chromatography–mass spectrometry applying online Paternò–Büchi reaction
Authors: Jeck Viola , Froning Matti , Tiso Till , Blank Lars M. , Hayen Heiko
Published: July 2020

Lipids are biomolecules with a broad variety of chemical structures, which renders them essential not only for various biological functions but also interestingly for biotechnological applications. Rhamnolipids are microbial glycolipids with surface-active properties and are widely used biosurfactants. They are composed of one or twol-rhamnoses and up to three hydroxy fatty acids. Their biosynthetic precursors are 3-hydroxy(alkanoyloxy)alkanoic acids (HAAs). The latter are also present in cell supernatants as complex mixtures and are extensively studied for their potential to replace synthetically derived surfactants. The carbon chain lengths of HAAs determine their physical properties, such as their abilities to foam and emulsify, and their critical micelle concentration. Despite growing biotechnological interest, methods for structural elucidation are limited and often rely on hydrolysis and analysis of free hydroxy fatty acids losing the connectivity information. Therefore, a high-performance liquid chromatography-mass spectrometry method was developed for comprehensive structural characterization of intact HAAs. Information is provided on chain length and number of double bonds in each hydroxy fatty acid and their linkage by tandem mass spectrometry (MS/MS). Post-column photochemical derivatization by online Paternὸ–Büchi reaction and MS/MS fragmentation experiments generated diagnostic fragments allowing structural characterization down to the double bond position level. Furthermore, the presented experiments demonstrate a powerful approach for structure elucidation of complex lipids by tailored fragmentation.
Steam and Flame Applications as Novel Methods of Population Control for Invasive Asian Clam (Corbicula fluminea) and Zebra Mussel (Dreissena polymorpha)
Authors: Coughlan Neil E. , Cunningham Eoghan M. , Potts Stephen , McSweeney Diarmuid , Healey Emma , Dick Jaimie T. A. , Vong Gina Y. W. , Crane Kate , Caffrey Joe M. , Lucy Frances E. , Davis Eithne , Cuthbert Ross N.
Published: July 2020

Control strategies for established populations of invasive alien species can be costly and complex endeavours, which are frequently unsuccessful. Therefore, rapid-reaction techniques that are capable of maximising efficacy whilst minimising environmental damage are urgently required. The Asian clam (Corbicula fluminea Müller, 1774), and the zebra mussel (Dreissena polymorpha Pallas, 1771), are invaders capable of adversely affecting the functioning and biodiversity of freshwater ecosystems. Despite efforts to implement substantial population-control measures, both species continue to spread and persist within freshwater environments. As bivalve beds often become exposed during low-water conditions, this study examined the efficacy of steam-spray (≥100 °C, 350 kPa) and open-flame burn treatments (~1000 °C) to kill exposed individuals. Direct steam exposure lasting for 5 min caused 100% mortality of C. fluminea buried at a depth of 3 cm. Further, combined rake and thermal shock treatments, whereby the substrate is disturbed between each application of either a steam or open flame, caused 100% mortality of C. fluminea specimens residing within a 4-cm deep substrate patch, following three consecutive treatment applications. However, deeper 8-cm patches and water-saturated substrate reduced maximum bivalve species mortality rates to 77% and 70%, respectively. Finally, 100% of D. polymorpha specimens were killed following exposure to steam and open-flame treatments lasting for 30 s and 5 s, respectively. Overall, our results confirm the efficacy of thermal shock treatments as a potential tool for substantial control of low-water-exposed bivalves. Although promising, our results require validation through upscaling to field application, with consideration of other substrate types, increased substrate depth, greater bivalve densities, non-target and long-term treatment effects.
Disturbances in the Biosynthesis or Signalling of Brassinosteroids That Are Caused by Mutations in the HvDWARF, HvCPD and HvBRI1 Genes Increase the Tolerance of Barley to the Deacclimation Process
Authors: Pociecha Ewa , Janeczko Anna , Dziurka Michał , Gruszka Damian
Published: July 2020

Tolerance to deacclimation is an important physiological feature in plants in the face of global warming, which is resulting in incidents of increases in winter temperatures. The aim of the work was to explore how disturbances in the signalling and synthesis of brassinosteroids (BR) influence the deacclimation tolerance of barley. One group of mutants and their reference cultivars (Bowman and Delisa) was cold-acclimated, deacclimated and then tested for frost tolerance at − 12 °C. After cold acclimation, the second group of plants was additionally exposed to frost (− 6 °C) and then, deacclimated and tested for frost tolerance at − 12 °C. The deacclimated brassinosteroid mutants were characterised by an increased tolerance to frost, and consequently, had a higher tolerance to deacclimation than their wild-type cultivars. The mechanism of this phenomenon may be partly explained by analysing the hormonal homeostasis in the crowns. For all of the tested plants, a characteristic feature of the response to the deacclimation phase was an increase in the growth-promoting hormones and abscisic acid compared to the cold acclimation phase. The increase was greater in the BR-deficient (BW084) and BR-insensitive (BW312) mutants compared to the Bowman reference cultivar. Mutant 522DK was characterised by a lower accumulation of total cytokinins and gibberellins as well as an enhanced auxin deactivation compared to the Delisa. In the second group, when the plants were exposed to a temperature of − 6 °C before deacclimation, the hormonal homeostasis was further altered in both the mutants and reference cultivars, but all of the mutants had a higher frost tolerance than the wild types.
Classical blood biomarkers identify patients with higher risk for relapse 6 months after alcohol withdrawal treatment
Authors: Raabe Florian J. , Wagner Elias , Weiser Judith , Brechtel Sarah , Popovic David , Adorjan Kristina , Pogarell Oliver , Hoch Eva , Koller Gabriele
Published: July 2020

This naturalistic study among patients with alcohol dependence examined whether routine blood biomarkers could help to identify patients with high risk for relapse after withdrawal treatment. In a longitudinal study with 6-month follow-up among 133 patients with alcohol dependence who received inpatient alcohol withdrawal treatment, we investigated the usefulness of routine blood biomarkers and clinical and sociodemographic factors for potential outcome prediction and risk stratification. Baseline routine blood biomarkers (gamma-glutamyl transferase [GGT], alanine aminotransferase [ALT/GPT], aspartate aminotransferase [AST/GOT], mean cell volume of erythrocytes [MCV]), and clinical and sociodemographic characteristics were recorded at admission. Standardized 6 months’ follow-up assessed outcome variables continuous abstinence, days of continuous abstinence, daily alcohol consumption and current abstinence. The combined threshold criterion of an AST:ALT ratio > 1.00 and MCV > 90.0 fl helped to identify high-risk patients. They had lower abstinence rates (P = 0.001), higher rates of daily alcohol consumption (P < 0.001) and shorter periods of continuous abstinence (P = 0.027) compared with low-risk patients who did not meet the threshold criterion. Regression analysis confirmed our hypothesis that the combination criterion is an individual baseline variable that significantly predicted parts of the respective outcome variances. Routinely assessed indirect alcohol biomarkers help to identify patients with high risk for relapse after alcohol withdrawal treatment. Clinical decision algorithms to identify patients with high risk for relapse after alcohol withdrawal treatment could include classical blood biomarkers in addition to clinical and sociodemographic items.
Cytokine regulation of apoptosis-induced apoptosis and apoptosis-induced cell proliferation in vascular smooth muscle cells
Authors: Aravani Dimitra , Foote Kirsty , Figg Nichola , Finigan Alison , Uryga Anna , Clarke Murray , Bennett Martin
Published: July 2020

Vascular smooth muscle cells (VSMCs) are the main structural cell of blood vessels, and VSMC apoptosis occurs in vascular disease, after injury, and in vessel remodeling during development. Although VSMC apoptosis is viewed as silent, recent studies show that apoptotic cells can promote apoptosis-induced compensatory proliferation (AICP), apoptosis-induced apoptosis (AIA), and migration of both local somatic and infiltrating inflammatory cells. However, the effects of VSMC apoptosis on adjacent VSMCs, and their underlying signaling and mechanisms are unknown. We examined the consequences of VSMC apoptosis after activating extrinsic and intrinsic death pathways. VSMCs undergoing apoptosis through Fas/CD95 or the protein kinase inhibitor staurosporine transcriptionally activated interleukin 6 (IL-6) and granulocyte-macrophage colony stimulating factor (GM-CSF), leading to their secretion. Apoptosis induced activation of p38MAPK, JNK, and Akt, but neither p38 and JNK activation nor IL-6 or GM-CSF induction required caspase cleavage. IL-6 induction depended upon p38 activity, while Fas-induced GM-CSF expression required p38 and JNK. Conditioned media from apoptotic VSMCs induced VSMC apoptosis in vitro, and IL-6 and GM-CSF acted as pro-survival factors for AIA. VSMC apoptosis was studied in vivo using SM22α-DTR mice that express the diphtheria toxin receptor in VSMCs only. DT administration induced VSMC apoptosis and VSMC proliferation, and also signficantly induced IL-6 and GM-CSF. We conclude that VSMC apoptosis activates multiple caspase-independent intracellular signaling cascades, leading to release of soluble cytokines involved in regulation of both cell proliferation and apoptosis. VSMC AICP may ameliorate while AIA may amplify the effects of pro-apoptotic stimuli in vessel remodeling and disease.
Building Science Gateways for Analysing Molecular Docking Results Using a Generic Framework and Methodology
Authors: Temelkovski Damjan , Kiss Tamas , Terstyanszky Gabor , Greenwell Pamela
Published: July 2020

Molecular docking and virtual screening experiments require large computational and data resources and high-level user interfaces in the form of science gateways. While science gateways supporting such experiments are relatively common, there is a clearly identified need to design and implement more complex environments for further analysis of docking results. This paper describes a generic framework and a related methodology that supports the efficient development of such environments. The framework is modular enabling the reuse of already existing components. The methodology, which proposes three techniques that the development team can use, is agile and encourages active participation of end-users. Based on the framework and methodology, two prototype implementations of science-gateway-based docking environments are presented and evaluated. The first system recommends a receptor-ligand pair for the next docking experiment, and the second filters docking results based on ligand properties.
Maximum likelihood estimators based on discrete component lifetimes of a k-out-of-n system
Authors: Dembińska Anna , Jasiński Krzysztof
Published: July 2020

This paper deals with parametric inference about the independent and identically distributed discrete lifetimes of components of a k-out-of-n system. We consider the maximum likelihood estimation assuming that the available data consists of component failure times observed up to and including the moment of the breakdown of the system. First, we provide general conditions for the almost sure existence of a strongly consistent sequence of maximum likelihood estimators (MLE’s). Then, we focus on three typical discrete failure distributions—the Poisson, binomial and negative binomial distributions—and prove that in these cases the MLE’s are unique, provided they exist, and that they are strongly consistent. Finally, we complete our results by Monte Carlo simulation study. Interestingly, the inference considered in the paper can be viewed as equivalent to one based on Type-II right censored discrete data. Therefore, our results can as well be applied to the case when Type-II right censored sample from a discrete distribution is observed.
A Review on Nano-Based Drug Delivery System for Cancer Chemoimmunotherapy
Authors: Mu Weiwei , Chu Qihui , Liu Yongjun , Zhang Na
Published: July 2020

Although notable progress has been made on novel cancer treatments, the overall survival rate and therapeutic effects are still unsatisfactory for cancer patients. Chemoimmunotherapy, combining chemotherapeutics and immunotherapeutic drugs, has emerged as a promising approach for cancer treatment, with the advantages of cooperating two kinds of treatment mechanism, reducing the dosage of the drug and enhancing therapeutic effect. Moreover, nano-based drug delivery system (NDDS) was applied to encapsulate chemotherapeutic agents and exhibited outstanding properties such as targeted delivery, tumor microenvironment response and site-specific release. Several nanocarriers have been approved in clinical cancer chemotherapy and showed significant improvement in therapeutic efficiency compared with traditional formulations, such as liposomes (Doxil®, Lipusu®), nanoparticles (Abraxane®) and micelles (Genexol-PM®). The applications of NDDS to chemoimmunotherapy would be a powerful strategy for future cancer treatment, which could greatly enhance the therapeutic efficacy, reduce the side effects and optimize the clinical outcomes of cancer patients. Herein, the current approaches of cancer immunotherapy and chemoimmunotherapy were discussed, and recent advances of NDDS applied for chemoimmunotherapy were further reviewed.
Cardiomyopathies in China: A 2018–2019 state‐of‐the‐art review
Authors: Hua Tian‐Rui , Zhang Shu‐Yang
Published: July 2020

Cardiomyopathies are diseases of the cardiac muscle and are often characterized by ventricular dilation, hypertrophy, and cardiac arrhythmia. Patients with cardiomyopathies often experience sudden death and cardiac failure and require cardiac transplantation during the course of disease progression. Early diagnosis, differential diagnosis, and genetic consultation depend on imaging techniques, genetic testing, and new emerging diagnostic tools such as serum biomarkers. The molecular genetics of cardiomyopathies has been widely studied recently. The discovery of mechanisms underlying heterogeneity and overlapping of the phenotypes of cardiomyopathies has revealed the existence of disease modifiers, and this has led to the emergence of novel disease‐modifying therapy. This 2018–2019 state‐of‐the‐art review outlines the pathogenesis, diagnosis, and treatment of cardiomyopathies in China.
Quantitative genome-wide association study of six phenotypic subdomains identifies novel genome-wide significant variants in autism spectrum disorder
Authors: Yousaf Afsheen , Waltes Regina , Haslinger Denise , Klauck Sabine M. , Duketis Eftichia , Sachse Michael , Voran Anette , Biscaldi Monica , Schulte-Rüther Martin , Cichon Sven , Nöthen Markus , Ackermann Jörg , Koch Ina , Freitag Christine M. , Chiocchetti Andreas G.
Published: July 2020

Autism spectrum disorders (ASD) are highly heritable and are characterized by deficits in social communication and restricted and repetitive behaviors. Twin studies on phenotypic subdomains suggest a differing underlying genetic etiology. Studying genetic variation explaining phenotypic variance will help to identify specific underlying pathomechanisms. We investigated the effect of common variation on ASD subdomains in two cohorts including >2500 individuals. Based on the Autism Diagnostic Interview-Revised (ADI-R), we identified and confirmed six subdomains with a SNP-based genetic heritability h2SNP = 0.2–0.4. The subdomains nonverbal communication (NVC), social interaction (SI), and peer interaction (PI) shared genetic risk factors, while the subdomains of repetitive sensory-motor behavior (RB) and restricted interests (RI) were genetically independent of each other. The polygenic risk score (PRS) for ASD as categorical diagnosis explained 2.3–3.3% of the variance of SI, joint attention (JA), and PI, 4.5% for RI, 1.2% of RB, but only 0.7% of NVC. We report eight genome-wide significant hits—partially replicating previous findings—and 292 known and novel candidate genes. The underlying biological mechanisms were related to neuronal transmission and development. At the SNP and gene level, all subdomains showed overlap, with the exception of RB. However, no overlap was observed at the functional level. In summary, the ADI-R algorithm-derived subdomains related to social communication show a shared genetic etiology in contrast to restricted and repetitive behaviors. The ASD-specific PRS overlapped only partially, suggesting an additional role of specific common variation in shaping the phenotypic expression of ASD subdomains.
Anticancer effects of the microbiota: how the microbiome shapes the development of IL-9-producing T cells
Authors: Apetoh Lionel
Published: July 2020

IL-9-producing T cells can harbour potent anti-cancer functions. In this issue of theBritish Journal of Cancer, Almeida et al. found that the host microbiota enhances in vivo T cell-derived secretion of IL-9, thereby limiting cancer outgrowth.
Prognostic value of nucleotyping, DNA ploidy and stroma in high-risk stage II colon cancer
Authors: Yang Lujing , Chen Pengju , Zhang Li , Wang Lin , Sun Tingting , Zhou Lixin , Li Zhongwu , Wu Aiwen
Published: July 2020

Background

Heterogeneity with respect to recurrence and survival in high-risk stage II colon cancer patients still exists, and further classification is urgently required. This study aimed to ascertain the prognostic value of DNA ploidy, stroma-tumour fraction and nucleotyping in the prognosis of high-risk stage II colon cancer.

Methods

A total of 188 high-risk stage II colon cancer patients received radical surgery in Peking University Cancer Hospital, from 2009 to 2015. Status of mismatch repair proteins in tumours was analysed using immunohistochemistry. DNA ploidy, stroma-tumour fraction and nucleotyping were estimated by automated digital imaging systems.

Results

Nucleotyping and DNA ploidy were significant prognostic factors, while stroma-tumour fraction were not significantly prognostic in the univariate analysis. In the multivariable model, the dominant contributory factor of disease-free survival was chromatin heterogeneous vs. chromatin homogeneous [HR 3.309 (95% CI: 1.668–6.564), P = 0.001].

Conclusions

Our study indicates that nucleotyping is an independent prognostic factor in high-risk stage II colon cancer. Therefore, it may help subdivide patients into different subgroups and give them different strategies for follow-up and treatment in the future.
Direct visualization of the conformational change of FUS/TLS upon binding to promoter-associated non-coding RNA
Authors: Hamad Nesreen , Watanabe Hiroki , Uchihashi Takayuki , Kurokawa Riki , Nagata Takashi , Katahira Masato
Published: July 2020

Conformational change of FUS protein detected by AFM upon binding of non-coding RNA provides a mechanistic insight into transcriptional regulation.
A study on the technical improvement and the crystalline quality optimization of columnar β-Ga2O3 crystal growth by an EFG method
Authors: Fu Bo , Mu Wenxiang , Zhang Jin , Wang Xiqiu , Zhuang Wenchang , Yin Yanru , Jia Zhitai , Tao Xutang
Published: July 2020

Innovative technology assessment and crystalline quality optimization of columnar β-Ga2O3 crystal growth were performed via an EFG method.
Recent advances in MOF-based nanoplatforms generating reactive species for chemodynamic therapy
Authors: Zhong Yuyu , Li Xiaosan , Chen Junhao , Wang Xiaoxiong , Wei Lintao , Fang Liqing , Kumar Abhinav , Zhuang ShuZe , Liu Jianqiang
Published: July 2020

This review focuses on summarizing the use of MOFs in CDT and their synergetic therapeutics as well as the challenges, obstacles, and development.