bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of the developmental neurotoxicity of silver nanoparticles and silver ions with mouse embryonic stem cells in vitro
Authors: Yin Nuoya , Hu Bowen , Yang Renjun , Liang Shaojun , Liang Shengxian , Faiola Francesco
Published: August 2018

The wide applications of silver nanoparticles (AgNPs) have raised many concerns worldwide regarding their safety. The few previous studies on the developmental toxicity of AgNPs have been mostly dependent on animal experiments, which are time‐consuming and costly. The rapid development of stem cell biology provides a new in vitro alternative to live animal assays for developmental toxicity studies. Here, we assessed the developmental neurotoxicity of AgNPs and Ag ions using a mouse embryonic stem cell (mESC) toxicology model. Our results showed that AgNP and Ag ion treatments did not affect mESC viability or cause accumulation of reactive oxygen species, at concentrations below 1 μg/mL. Conversely, AgNPs and Ag ions perturbed mESC global and neural progenitor cell‐specific differentiation processes. In fact, both AgNPs and Ag ions induced the anomalous expression of neural ectoderm marker genes, such as Sox1, Sox3, Map2, NeuroD, Nestin, and Pax6, at concentrations lower than 0.1 μg/mL. Interestingly, AgNP effects manifested at earlier time points as compared with Ag ions. In addition, treatment with Ag ions generated neural progenitor cell abnormal morphology. Overall, our data proved that both AgNPs and Ag ions are toxicants, and their toxic effects are somehow different.
Academic productivity in surgical oncology: Where is the bar set for those training the next generation?
Authors: LaRocca Christopher J. , Wong Paul , Eng Oliver S. , Raoof Mustafa , Warner Susanne G. , Melstrom Laleh G.
Published: August 2018

Background and Objectives

Promotion and tenure are important milestones for academic surgical oncologists. The aim of this study was to quantify academic metrics associated with rank in surgical oncologists training the next generation.

Methods

Faculty were identified from accredited surgical oncology fellowships in the United States. Scopus was used to obtain the number of publications/citations and h‐index values. The National Institutes of Health (NIH) RePORT website was used to identify funding history.

Results

Of the 319 surgeons identified, complete rank information was obtained for 308. The majority of faculty were men (70%) and only 11% of full professors were women. The median h‐index values were 7, 17, and 39 for assistant, associate, and full professors, respectively. While 50% of full professors had a history of NIH funding, only 26% had RO1s and 20% had current NIH funding. Using multivariate analysis, years in practice, h‐index, and a history of NIH funding were associated with academic rank (P < .05).

Conclusion

Objective benchmarks, such as the median h‐index and NIH funding, provide additional insights for both junior faculty and leadership into the productivity needed to attain promotion to the next academic rank for surgical oncologists.
Fully nonhomogeneous problem of two‐dimensional second grade fluids
Authors: Bernard Jean‐marie
Published: August 2018

This article studies the solutions of a two‐dimensional grade‐two fluid model with a fully nonhomogeneous boundary condition for velocity u. Compared to problems with a homogeneous or tangential boundary condition, studied by many authors, we must add a boundary condition, otherwise the problem is no longer well posed. We propose two conditions on z = curl (u − αΔu), which differ according to the regularity of z, on the portion of ∂Ω where αu . n < 0. Following the approach of V. Girault and L.R. Scott in the tangential boundary case, we split the problem into a system with a generalized Stokes problem and a transport problem. However, compared to the study of these authors, we are now led to solve transport problems with boundary conditions. In two previous articles, we studied these transport problems. The results obtained in these articles allow us, by a fixed‐point argument, to establish existence of the solutions for the fully nonhomogeneous grade‐two problem. Uniqueness requires the boundary condition with z in H1.
Lightlike surfaces of Darboux‐like indicatrixes and binormal indicatrixes of spacelike curves in lightcone 3‐space
Authors: Xu Huimin , Wang Zhigang
Published: August 2018

In this paper, by introducing a new frame on spacelike curves lying in lightcone 3‐space, we investigate the geometric properties of the lightlike surface of the Darboux‐like indicatrix and the lightlike surface of the binormal indicatrix generated by spacelike curves in lightcone 3‐space. As an extension of our previous work and an application of the singularity theory, the singularities of the lightlike surfaces of the Darboux‐like indicatrix and the lightlike surface of the binormal indicatrix are classified, several new invariants of spacelike curves are discovered to be useful for characterizing these singularities, meanwhile, it is found that the new invariants also measure the order of contact between spacelike curves or principal normal indicatrixes of spacelike curves located in lightcone 3‐space and two‐dimensional lightcone whose vertices are at the singularities of lightlike surfaces. One concrete example is provided to illustrate our results.
Periodic and almost periodic solutions for the damped Korteweg‐de Vries equation
Authors: Chen Mo
Published: August 2018

The Korteweg‐de Vries equation is an important model for propagation of some surface water waves along a channel. In this paper, we discuss the damped Korteweg‐de Vries equation in a bounded domain. First, we study the existence and uniqueness of the strong solution. Then, we prove that the strong solution is periodic (or almost periodic) if the coefficient and external force are periodic (or almost periodic).
The trickle‐down effect of ethical leadership in nonprofit soccer clubs
Authors: Constandt Bram , Willem Annick
Published: August 2018

Nonprofit soccer clubs are currently facing many ethical challenges, such as abuse, doping and match fixing. While research suggests that organizational (board) ethical leadership may be effective to tackle these ethical issues, empirical support in the context of sport remains limited. Drawing on the perceptions of a sample of nonprofit soccer players (n = 438) and coaches (n = 106), we indicate that the coaches play an important mediating role regarding the associations between board ethical leadership and ethical climate. The theoretical underpinnings of ethical leadership—formed by social learning theory and social exchange theory—and the social distance between the board and the players in nonprofit soccer clubs provide support in this regard. In sum, our results demonstrate that the influence of board ethical leadership in nonprofit soccer clubs partly trickles down to the players via coach ethical leadership. Finally, practical implications for nonprofit soccer club management are discussed.
Parental concerns of allergy or hypersensitivity and the infant’s diet
Authors: Holmberg Fagerlund Bettina , Helseth Sølvi , Andersen Lene Frost , Småstuen Milada Cvancarova , Glavin Kari
Published: August 2018

Aim

To investigate a possible association between children's current diet and parents’ reported avoidance of appropriate foods in the child's diet at the age of 10 months, due to fears of allergic or hypersensitivity reactions.

Design

A cross‐sectional study.

Methods

In 10 randomly selected municipalities willing to participate, 686 children represented by their parents visiting the child health centre were enrolled in the study. From January 2015–January 2017, 440 (64%) parents completed a semi‐quantitative food frequency questionnaire concerning their child.

Results

Thirty‐four percent of parents reported that they avoided introducing some food items due to fears of allergy or hypersensitivity in their child. A statistically significant relationship emerged between this reporting and parents wanting more information about food for infants and toddlers. However, the reported fear was not associated with dietary restrictions regarding actual feeding of the child.
Developmental dynamics of stem starch accumulation in Sorghum bicolor
Authors: McKinley Brian A. , Casto Anna L. , Rooney William L. , Mullet John E.
Published: August 2018

Sweet sorghums were identified that accumulate up to ~9% of their total stem dry weight as starch. Starch accumulated preferentially in stem pith parenchyma in close proximity to vascular bundles. Stem starch accumulated slowly between floral initiation and anthesis and more rapidly between anthesis and 43 days post‐anthesis before declining in parallel with tiller outgrowth. Genes involved in stem starch metabolism were identified through phylogenetic approaches and RNA‐seq analysis of Della stem gene expression during the starch accumulation phase of development. Genes differentially expressed in stems were identified that are involved in starch biosynthesis (i.e., AGPase SS/LS, starch synthases, starch‐branching enzymes), degradation (i.e., glucan‐water dikinase, β‐amylase, disproportionating enzyme, alpha‐glucan phosphorylase) and amyloplast sugar transport (glucose‐6‐P translocator). Transcripts encoding AGPase SS and LS subunits with plastid localization were differentially induced during stem starch accumulation indicating that ADP‐glucose for starch biosynthesis is primarily generated in stem plastids. Cytosolic heteroglucan metabolism may play a role in stem sucrose/starch accumulation because genes encoding cytosolic forms of the disproportionating enzyme and alpha‐glucan phosphorylase were induced in parallel with stem sucrose/starch accumulation. Information on the stem starch pathway obtained in this study will be useful for engineering sorghum stems with elevated starch thereby improving forage quality and the efficiency of biomass conversion to biofuels and bio‐products.
The excited state hydrogen bond and proton transfer mechanism of a novel dye CS‐Azine
Authors: Jia Min , Yang Guang , Song Xiaoyan , Zhang Qiaoli , Yang Dapeng
Published: August 2018

In this work, based on density functional theory (DFT) and time‐dependent DFT (TDDFT) methods, we theoretically explore the excited state behavior for a novel dye molecule 3,3′‐(5,5′‐((1E,1E′)‐hydrazine‐1,2‐diylidenebis (methanylylidene))bis(2‐morpholinothiazole‐5,4‐diyl))bis(4‐hydroxy‐2H‐chromen‐2‐one) (CS‐Azine). Coupling with atoms in molecules, we investigate the intramolecular dual hydrogen bonds of CS‐Azine system and verify the formation of them. Via study the primary bond distances, bond angle, and infrared vibrational spectra involved in hydrogen bonding moieties, we find O1‐H2···N3 and O4‐H5···N6 of CS‐Azine should be strengthened in the S1 state. When exploring the photo‐excitation process, we confirm that the charge redistribution around hydrogen bonding moieties reveals the tendency of ESIPT reaction. To further investigate whether single or double proton transfer occurs in the S1 state, we consider two kinds of reaction paths (ie, the stepwise and synergetic ESIPT reactions). And the constructed potential energy curves demonstrate that only the single proton transfer reaction should be the most supported in the S1 state from CS‐Azine to CS‐Azine‐SPT form due to the low potential energy barrier. This work not only clarifies the excited state behavior and mechanism about CS‐Azine system but also paves the way for further applying CS‐Azine dye in future.
g‐C3N4‐Modified Water‐Crystallized Mesoporous SnO2 for Enhanced Photoelectrochemical Properties
Authors: Bian Haidong , Wang Aiwu , Li Zebiao , Li Zhe , Diao Yingxue , Lu Jian , Li Yang Yang
Published: August 2018

A novel type of high‐performance photoelectrochemical (PEC) electrode is conveniently fabricated. Graphitic carbon nitride (g‐C3N4) nanodots are homogeneously deposited inside an amorphous host of mesoporous 1D SnO2 via pulsed electrophoresis, followed by extremely facile water‐soaking treatment to crystallize the amorphous SnO2. The g‐C3N4/SnO2 nanocomposite thus obtained readily serves as a PEC electrode that is able to extend the light absorption to the visible region, delivering a photocurrent density of 1.8 mA cm−2 at 0.2 V (vs Ag/AgCl) under simulated solar light irradiation, which is ≈1.5 times higher than that of pristine SnO2 host. The facile and mild electrophoresis/water‐soaking method reported here can be extended to fabricate other high performance photoelectrode systems from various anodic mesoporous materials and nanoparticles.
Soluble tau aggregates, not large fibrils, are the toxic species that display seeding and cross‐seeding behavior
Authors: Ghag Gaurav , Bhatt Nemil , Cantu Daniel V. , Guerrero‐Munoz Marcos J. , Ellsworth Anna , Sengupta Urmi , Kayed Rakez
Published: August 2018

Several studies have proposed that fibrillary aggregates of tau and other amyloidogenic proteins are neurotoxic and result in numerous neurodegenerative diseases. However, these studies usually involve sonication or extrusion through needles before experimentation. As a consequence, these methods may fragment large aggregates producing a mixture of aggregated species rather than intact fibrils. Therefore, the results of these experiments may be reflective of other amyloidogenic species, such as oligomers and/or protofibrils/short fibrils. To investigate the effects of sonication on the aggregation of tau and other amyloidogenic proteins, fibrils were prepared and well characterized, then sonicated and evaluated by various biochemical and biophysical methods to identify the aggregated species present. We found that indeed a mixture of aggregated species was present along with short fibrils indicating that sonication leads to impure fibril samples and should be analyzed with caution. Our results corroborate the previous studies showing that sonication of prion and Aβ fibrils leads to the formation of toxic, soluble aggregates. We also show that the oligomeric forms are the most toxic species although it is unclear how sonication causes oligomer formation. Recent results suggest that these small toxic oligomers produced by sonication, rather than the stable fibrillar structures, are prion‐like in nature displaying seeding and cross‐seeding behavior.
Robust fault estimation based on zonotopic Kalman filter for discrete‐time descriptor systems
Authors: Wang Ye , Puig Vicenç , Cembrano Gabriela
Published: August 2018

This paper proposes a set‐based approach for robust fault estimation of discrete‐time descriptor systems. The considered descriptor systems are subject to unknown‐but‐bounded uncertainties (state disturbances and measurement noise) in predefined zonotopes and additive actuator faults. The zonotopic fault estimation filter for descriptor systems is built based on fault detectability indices and matrix to estimate fault magnitude in a deterministic set. The zonotopic fault estimation filter gain is designed in a parameterized form. Within a set‐based framework, following the zonotopic Kalman filter, the optimal filter gain is computed by minimizing the size of the corresponding zonotopes to achieve robustness against uncertainties and the identification of occurred actuator faults. Besides, boundedness of the proposed zonotopic fault estimation is analyzed, which proves that the size of obtained fault estimation bounds is not growing in time. Finally, the simulation results with two application examples are provided to show the effectiveness of the proposed approach.
1,10‐Phenanthroline‐Based Molten Salt as a Bifunctional Sulfonic Acid Catalyst: Application to the Synthesis of N‐Heterocycle Compounds via Anomeric Based Oxidation
Authors: Babaee Saeed , Zolfigol Mohammad Ali , Zarei Mahmoud , Zamanian Javad
Published: August 2018

1,10‐phenanthroline‐based molten salt as a bifunctional sulfonic acid [Phen(SO3H)2]Cl2 was designed and synthesized. The described nano molten salt has two SO3H acid groups and a rigid structure that allows the rotation of the molecule to have a unique catalytic ability. This catalyst was applied for the synthesis of N‐heterocyclic compounds such as quinazolines, quinazolinones, acridines and dihydropyridines via multi‐component condensation reactions. These compounds are highly regarded for their medicinal and biological properties. The effect of different functional groups at the corresponding products for developing the new mechanisem entitled “anomeric based oxidation” (ABO) were studied. The major advantages of the presented methodology are mild conditions, high efficiency, short reaction times and reusability of the catalyst.
New Five Coordinate Ru(II) Carbonyl Complexes Containing 2‐Aminofluorene Schiff Base Derivatives: Synthesis, Structure and Catalytic Activity
Authors: Ramesh Madhan , Venkatachalam Galmari
Published: August 2018

The monometallic five coordinated ruthenium(II) Schiff base complexes of the general type [Ru(CO)(EPh3)2(L1−3)]Cl (E=P or As) have been synthesized and characterized by analytical and spectral (FT−IR, UV−Vis and1H NMR) methods. The electronic spectra of the complexes indicate the presence of intense MLCT transitions in the visible region. The molecular structure of the complex [Ru(CO)(PPh3)2(L3)]Cl5was characterized by single crystal X−ray diffraction studies, which revealed that the Schiff base ligands coordinated to the ruthenium(II) ion as mono anionic bidentate (O, N) donor forming six membered chelating rings. Further, the five coordinate [Ru(CO)(PPh3)2(L3)]Cl5complex was found efficiently to catalyze the formation of amides from various substituted aldehyde and showing higher catalytic activity in the presence of NH2OH.HCl and NaHCO3and the yield was up to 97%.
Recent Advances in Applying Vulcanization/Inverse Vulcanization Methods to Achieve High‐Performance Sulfur‐Containing Polymer Cathode Materials for Li–S Batteries
Authors: Zhao Fulai , Li Yu , Feng Wei
Published: August 2018

Lithium–sulfur (Li–S) batteries have great prospects as next‐generation energy storage devices because of their high energy density, inexpensive raw materials, and low pollution. However, the development of Li–S batteries is currently restricted by the shuttle effect that occurs during the charge–discharge process. Sulfur‐containing polymers are attractive for use as Li–S battery cathode materials to alleviate the shuttle effect through chemical bonds as well as physical confinement. Moreover, polymers have numerous different molecular structures and definable functional groups. A suitable monomer design can result in a final sulfur‐containing polymer possessing favorable properties such as ion and electron conductivity, high sulfur content, appropriate viscosity, processability, and controllable morphology. These characteristics are of great benefit for use in Li–S battery cathodes to achieve high capacity and stable discharge at high rates. This review summarizes recent developments in sulfur‐containing polymer cathode materials. Focusing on polymers prepared by the facile and low‐cost vulcanization/inverse vulcanization methods and the polymer‐based composites, the chemical structures and electrochemical mechanisms are clarified, and the relationship between their structures and performances is discussed comprehensively. It is expected that more polymer electrode materials with high performance will emerge in the coming years.
A systematic review on security issues in vehicular ad hoc network
Authors: Tanwar Sudeep , Vora Jayneel , Tyagi Sudhanshu , Kumar Neeraj , Obaidat Mohammad S.
Published: August 2018

Vehicular ad hoc networks (VANETs) have been widely used in intelligent transportation system to provide safety and security alongwith reduction in traffic jam using vehicle‐to‐vehicle (V2V) and vehicle‐to‐roadside (V2R) unit communications. However, one of the major concerns in VANETs is to maintain the privacy and security of the sensitive information shared between vehicles and end‐users, as information leakage can influence any implemented solution in this environment. Keeping view on the above‐mentioned points, this paper provides a detailed survey on various types of attacks and possible solutions to handle these attacks. Using the proposed survey, a detailed taxonomy based upon the types of attacks and possible solutions to handle these attacks is proposed. Finally, various emerging open issues and challenges along with the security threats are identified and discussed in the paper. These open research issues motivate the communities to design new solutions to mitigate the existing new security threats in this area.
The size‐dependent apoptotic effect of titanium dioxide nanoparticles on endothelial cells by the intracellular pathway
Authors: Zeng Can , Feng Yuqin , Wang Wuxiang , Zhou Furong , Liao Fen , Liu Yuanfeng , Feng Shaolong
Published: August 2018

Concerns over the health risk of the widely distributed, commonly used titanium dioxide nanoparticles (nano‐TiO2) are increasing worldwide. Yet, up‐to‐now, our understanding in their potential effects on the cardiovascular system is very limited and the toxicological mechanisms are still unclear. In the present study, the CCK‐8 assay was performed to determine the cytotoxicity of four sizes (10, 30, 50, and 100 nm) of anatase nano‐TiO2 on human umbilical vein endothelial cells (HUVECs) in culture, and the flow cytometry was employed to investigate the potential of these nano‐TiO2 to induce the apoptosis of HUVECs. The apoptotic pathway was also probed through the determination of the protein expression and activation of p53, Bax, Bcl‐2, caspases‐9, ‐7, ‐3, and PARP by western blot. The results showed that at the administrative levels (1, 5, 25 μg/mL), all the four sizes of nano‐TiO2 could significantly inhibit the viability of HUVECs and elicit significant apoptosis in them, compared with the negative control (P < .05, P < .01). Moreover, the apoptotic rates of HUVECs were increased respectively with the elevating levels and decreasing sizes of the administrative nano‐TiO2, showing a clear dose‐ and size‐dependent effect relationships. Interestingly, the increasing phosphorylation of p53, decreasing ratio of Bcl‐2/Bax, and enhancing activation of the downstream proteins caspase‐9, ‐7, ‐3, and PARP, were also observed with the decreasing sizes of the administrative nano‐TiO2 in the western blot, indicating that the intracellular approach of apoptosis, the p53‐caspase pathway, is the major way of the nano‐TiO2‐mediated apoptosis in HUVECs in culture and that the size is an important parameter that may determine the potential of nano‐TiO2 to induce cellular response. In conclusion, these results suggested that high levels of nano‐TiO2 exposure may pose potential risks to human cardiovascular health by inducing cardiovascular EC apoptosis.
Perinatal mortality, timing of delivery and prenatal management of monoamniotic twin pregnancy: systematic review and meta‐analysis
Authors: D'Antonio F. , Odibo A. , Berghella V. , Khalil A. , Hack K. , Saccone G. , Prefumo F. , Buca D. , Liberati M. , Pagani G. , Acharya G.
Published: August 2018

Objective

To quantify the rate of perinatal mortality in monochorionic monoamniotic (MCMA) twin pregnancies, according to gestational age, and to ascertain the incidence of mortality in pregnancies managed as inpatients compared with those managed as outpatients.

Methods

MEDLINE, EMBASE and CINAHL databases were searched for studies on monoamniotic twin pregnancy. The primary outcomes explored were the incidence of intrauterine death (IUD), neonatal death (NND) and perinatal death (PND) in MCMA twins at different gestational‐age windows (24–30, 31–32, 33–34, 35–36 and ≥ 37 weeks of gestation). The secondary outcomes were the incidence of IUD, NND and PND in MCMA twins according to the type of fetal monitoring (inpatient vs outpatient), and the incidence of delivery ahead of schedule. Random‐effects model meta‐analyses were used to analyze the data.

Results

Twenty‐five studies (1628 non‐anomalous twins reaching 24 weeks of gestation) were included. Single and double intrauterine deaths occurred in 2.5% (95% CI, 1.8–3.3%) and 3.8% (95% CI, 2.5–5.3%) of cases, respectively. IUD occurred in 4.3% (95% CI, 2.8–6.2%) of twins at 24–30 weeks, in 1.0% (95% CI, 0.6–1.7%) at 31–32 weeks and in 2.2% (95% CI, 0.9–3.9%) at 33–34 weeks of gestation, while there was no case of IUD, either single or double, from 35 weeks of gestation. In MCMA twin pregnancies managed mainly as inpatients, the incidence of IUD was 3.0% (95% CI, 1.4–5.2%), while the corresponding figure for those managed mainly as outpatients was 7.4% (95% CI, 4.4–11.1%). Finally, 37.8% (95% CI, 28.0–48.2%) of MCMA pregnancies were delivered before the scheduled time, due mainly to spontaneous preterm labor or abnormal cardiotocographic findings.

Conclusions

MCMA twins are at high risk of perinatal loss during the third trimester of pregnancy, with the large majority of such losses occurring as apparently unexpected events. Inpatient management seems to be associated with a lower rate of mortality, although further studies are needed in order to establish the appropriate type and timing of prenatal assessment in these pregnancies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.
Towards non‐invasive in vivo characterization of the pathophysiological state and mechanical wall strength of the individual human AAA wall based on 4D ultrasound measurements
Authors: Wittek Andreas , Derwich Wojciech , Fritzen Claus‐Peter , Schmitz‐Rixen Thomas , Blase Christopher
Published: August 2018

Abdominal aortic aneurysms (AAA) are a degenerative disease of the aorta with high associated mortality. Currently, there is a lack of in vivo information, which allows to characterise the individual aneurysmal wall with regard to wall strength or rupture risk. We have used 4D ultrasound strain imaging to compute the spatially resolved distribution of the in‐plane strain tensor and of the local distensibility in three patient groups (young, < 40 y. o.; elderly, > 60 y. o.; AAA). Mean and local maximum deformation and distensibility as well as indices for the local variations of the strain and the distensibility distribution were determined. Mean distensibility is significantly decreasing from young (3.83 [2.83, 5.87] 10−3 mmHg−1) to elderly (0.67 [0.39, 0.87] 10−3 mmHg−1) and AAA (0.27 [0.20, 0.54] 10−3 mmHg−1). Both indices characterising the heterogeneous elastic behaviour are significantly increasing from young through elderly to AAA. Linear dependency of some of the distensibility distribution indices on age and aortic diameter was observed in the young and elderly group. In contrast, none of the indices depended on age or maximum diameter in the AAA group. We hypothesize that the heterogeneous distensibility distribution is indicative of microstructural changes in the aortic and aneurysmal wall and might contribute to a more complete and informative pathophysiological characterisation of the AAA wall, either with respect to wall strength or rupture risk. To confirm this hypothesis, further studies will be necessary in which the correlation between the proposed indices and individual wall strength and rupture risk is tested.
c-Recursion for multi-point superconformal blocks. NS sector
Authors: Belavin Vladimir , Geiko Roman
Published: August 2018

Abstract

We develop a recursive approach to computing Neveu-Schwarz conformal blocks associated with n-punctured Riemann surfaces. This work generalizes the results of [1] obtained recently for the Virasoro algebra. The method is based on the analysis of the analytic properties of the superconformal blocks considered as functions of the central charge c. It consists of two main ingredients: the study of the singular behavior of the conformal blocks and the analysis of their asymptotic properties when c tends to infinity. The proposed construction is applicable for computing multi-point blocks in different topologies. We consider some examples for genus zero and one with different numbers of punctures. As a by-product, we propose a new way to solve the recursion relations, which gives more efficient computational procedure and can be applied to SCFT case as well as to pure Virasoro blocks.
Adhesive wear and particle emission: Numerical approach based on asperity-free formulation of Rabinowicz criterion
Authors: Popov Valentin L. , Pohrt Roman
Published: August 2018

In 1953 Archard formulated his general law of wear stating that the amount of worn material is proportional to the normal force and the sliding distance, and is inversely proportional to the hardness of the material. Five years later in 1958, Rabinowicz suggested a criterion determining the minimum size of wear particles. Both concepts became very popular due to their simplicity and robustness, but did not give thorough explanation of the mechanisms involved. It wasn’t until almost 60 years later in 2016 that Aghababaei, Warner and Molinari (AWM) used quasi-molecular simulations to confirm the Rabinowicz criterion. One of the central quantities remained the “asperity size”. Because real surfaces have roughness on many length scales, this size is often ill-defined. The present paper is devoted to two main points: First, we generalize the Rabinowicz-AWM criterion by introducing an “asperity-free” wear criterion, applicable even to fractal roughness. Second, we combine our generalized Rabinowicz criterion with the numerical contact mechanics of rough surfaces and formulate on this basis a deterministic wear model. We identify two types of wear: one leading to the formation of a modified topography which does not wear further and one showing continuously proceeding wear. In the latter case we observe regimes of least wear, mild wear and severe wear which have a clear microscopic interpretation. The worn volume in the region of mild wear occurs typically to be a power law of the normal force with an exponent not necessarily equal to one. The method provides the worn surface topography after an initial settling phase as well as the size distribution of wear particles. We analyse different laws of interface interaction and the corresponding wear laws. A comprehensive parameter study remains a task for future research.
POWDERMET2018 overview
Authors: Capus Joseph
Published: August 2018

Following modest growth in 2017 for the North American PM and MIM industries, MPIF reported a favorable outlook for 2018 despite a serious shortage of skilled employees. The concurrently-held POWDERMET and AMPM conferences continue to surpass previous successes.
Sea-water sulphate removal unit provides vital protection for oilfield production wells
Authors: Atkinson Simon
Published: August 2018

Norwegian multinational energy company Equinor ASA – formerly Statoil – has selected a sea-water sulphate removal system designed by SUEZ and Halvorsen TEC for use in its Johan Castberg Project in Norway. The membrane-based system removes sulphate from sea water before it is injected into oil reservoirs to maintain or enhance oil production.
Silurian amplexoid rugose coral generaPilophylliaGe and Yu, 1974 andNeopilophyllianew genus from South China
Authors: Wang Guang-Xu , He Xin-Yi , Tang Lan , Percival Ian G.
Published: August 2018

PilophylliaGe and Yu, 1974 represents a major group of distinctive amplexoid corals in the Silurian, whose taxonomic relationships, species composition, and evolutionary trends remain contentious. A critical revision of type material and new specimens of several species (and subspecies) assigned toPilophyllia, including the type speciesP. involutaGe and Yu, 1974, provides solutions to some of these problems.Pilophylliais revised to include only those forms characterized by a distinct peripheral stereozone and amplexoid major septa with club-shaped rhabdacanths set in thick lamellar stereomes. Other species, previously referred toPilophylliabut having generally short septa with wedge-shaped rhabdacanths, are transferred herein to the new genusNeopilophylliaWang. Both genera, together with other Silurian amplexoid rugosan genera such asAmplexoides, are referred to the new family Amplexoididae Wang, which is thought to be evolutionarily unrelated to the much younger (Devonian to early Carboniferous) amplexoid rugosan family Amplexidae Chapman, 1893. The first appearance ofNeopilophyllian. gen. in the middle Telychian, much later than that ofPilophylliain the late Rhuddanian, probably marks a significant stage during the evolution of Silurian amplexoid corals.

UUID:http://zoobank.org/c22423b0-7af2-4be0-8ac2-7d47addde621
Unconventional calibration strategies for micromanipulation work-cells
Authors: Fontana G. , Ruggeri S. , Legnani G. , Fassi I.
Published: August 2018

This paper presents and compares a set of calibration strategies useful to calibrate vision-based robotised work-cells for micromanipulation and microassembly. To grasp and release microparts precisely, robot calibration, camera calibration and robot-camera registration are needed. Conventional calibration methods are very onerous at the microscale, therefore, two alternative unconventional procedures, called virtual grid calibration and hybrid calibration, are developed for work-cells with high-performance robots, minimising necessary instrumentation. Moreover, an effective calibration of the robot end-effector is designed to compensate for misalignment and orientation errors with respect to the vertical rotational axis. This paper describes the calibration methods and their implementation, the results and the improvements achieved. A detailed comparison between the hybrid and the virtual grid calibrations is provided, demonstrating the higher performance of the latter strategy.
The Order of Knowledge: From Disciplinarity to Transdisciplinarity and Back
Authors: Mittelstrass Jürgen
Published: August 2018

The concept of transdisciplinarity has found a foothold in science. It is increasingly taking the place of the concept of interdisciplinarity and is making the concept of disciplinarity look pale. However, the concept of transdisciplinarity is not self-explanatory – as it is often understood – and the concept of disciplinarity is not at all outdated – as it seems. This becomes clear in the conceptual analysis of the concepts of disciplinarity, interdisciplinarity and transdisciplinarity.
Extending the paradigm: a policy framework for healthy and equitable eating (HE2)
Authors: Pescud Melanie , Friel Sharon , Lee Amanda , Sacks Gary , Meertens Elizabeth , Carter Rob , Cobcroft Megan , Munn Elizabeth , Greenfield Joanne
Published: August 2018

Objective

The current short communication aimed to provide a new conceptualisation of the policy drivers of inequities in healthy eating and to make a call to action to begin populating this framework with evidence of actions that can be taken to reduce the inequities in healthy eating.

Design

The Healthy and Equitable Eating (HE2) Framework derives from a systems-based analytical approach involving expert workshops.

Setting

Australia.

Subjects

Academics, government officials and non-government organisations in Australia.

Results

The HE2Framework extends previous conceptualisations of policy responses to healthy eating to include the social determinants of healthy eating and its social distribution, encompassing policy areas including housing, social protection, employment, education, transport, urban planning, plus the food system and environment.

Conclusions

As the burden of non-communicable diseases continues to grow globally, it is important that governments, practitioners and researchers focus attention on the development and implementation of policies beyond the food system and environment that can address the social determinants of inequities in healthy eating.
Design principles of chiral carbon nanodots help convey chirality from molecular to nanoscale level
Authors: Ðorđević Luka , Arcudi Francesca , D’Urso Alessandro , Cacioppo Michele , Micali Norberto , Bürgi Thomas , Purrello Roberto , Prato Maurizio
Published: August 2018

The chirality of (nano)structures is paramount in many phenomena, including biological processes, self-assembly, enantioselective reactions, and light or electron spin polarization. In the quest for new chiral materials, metallo-organic hybrids have been attractive candidates for exploiting the aforementioned scientific fields. Here, we show that chiral carbon nanoparticles, called carbon nanodots, can be readily prepared using hydrothermal microwave-assisted synthesis and easily purified. These particles, with a mean particle size around 3 nm, are highly soluble in water and display mirror-image profile both in the UV–Vis and in the infrared regions, as detected by electronic and vibrational circular dichroism, respectively. Finally, the nanoparticles are used as templates for the formation of chiral supramolecular porphyrin assemblies, showing that it is possible to use and transfer the chiral information. This simple (and effective) methodology opens up exciting opportunities for developing a variety of chiral composite materials and applications.
The dual methyltransferase METTL13 targets N terminus and Lys55 of eEF1A and modulates codon-specific translation rates
Authors: Jakobsson Magnus E. , Małecki Jędrzej M. , Halabelian Levon , Nilges Benedikt S. , Pinto Rita , Kudithipudi Srikanth , Munk Stephanie , Davydova Erna , Zuhairi Fawzi R. , Arrowsmith Cheryl H. , Jeltsch Albert , Leidel Sebastian A. , Olsen Jesper V. , Falnes Pål Ø.
Published: August 2018

Eukaryotic elongation factor 1 alpha (eEF1A) delivers aminoacyl-tRNA to the ribosome and thereby plays a key role in protein synthesis. Human eEF1A is subject to extensive post-translational methylation, but several of the responsible enzymes remain unknown. Using a wide range of experimental approaches, we here show that human methyltransferase (MTase)-like protein 13 (METTL13) contains two distinct MTase domains targeting the N terminus and Lys55 of eEF1A, respectively. Our biochemical and structural analyses provide detailed mechanistic insights into recognition of the eEF1A N terminus by METTL13. Moreover, through ribosome profiling, we demonstrate that loss of METTL13 function alters translation dynamics and results in changed translation rates of specific codons. In summary, we here unravel the function of a human MTase, showing that it methylates eEF1A and modulates mRNA translation in a codon-specific manner.
p53 in AgRP neurons is required for protection against diet-induced obesity via JNK1
Authors: Quiñones Mar , Al-Massadi Omar , Folgueira Cintia , Bremser Stephan , Gallego Rosalía , Torres-Leal Leonardo , Haddad-Tóvolli Roberta , García-Caceres Cristina , Hernandez-Bautista Rene , Lam Brian Y. H. , Beiroa Daniel , Sanchez-Rebordelo Estrella , Senra Ana , Malagon Jose A. , Valerio Patricia , Fondevila Marcos F. , Fernø Johan , Malagon Maria M. , Contreras Raian , Pfluger Paul , Brüning Jens C. , Yeo Giles , Tschöp Matthias , Diéguez Carlos , López Miguel , Claret Marc , Kloppenburg Peter , Sabio Guadalupe , Nogueiras Ruben
Published: August 2018

p53 is a well-known tumor suppressor that has emerged as an important player in energy balance. However, its metabolic role in the hypothalamus remains unknown. Herein, we show that mice lacking p53 in agouti-related peptide (AgRP), but not proopiomelanocortin (POMC) or steroidogenic factor-1 (SF1) neurons, are more prone to develop diet-induced obesity and show reduced brown adipose tissue (BAT) thermogenic activity. AgRP-specific ablation of p53 resulted in increased hypothalamic c-Jun N-terminal kinase (JNK) activity before the mice developed obesity, and central inhibition of JNK reversed the obese phenotype of these mice. The overexpression of p53 in the ARC or specifically in AgRP neurons of obese mice decreased body weight and stimulated BAT thermogenesis, resulting in body weight loss. Finally, p53 in AgRP neurons regulates the ghrelin-induced food intake and body weight. Overall, our findings provide evidence that p53 in AgRP neurons is required for normal adaptations against diet-induced obesity.
Loss of the E3 ubiquitin ligase MKRN1 represses diet-induced metabolic syndrome through AMPK activation
Authors: Lee Min-Sik , Han Hyun-Ji , Han Su Yeon , Kim Il Young , Chae Sehyun , Lee Choong-Sil , Kim Sung Eun , Yoon Seul Gi , Park Jun-Won , Kim Jung-Hoon , Shin Soyeon , Jeong Manhyung , Ko Aram , Lee Ho-Young , Oh Kyoung-Jin , Lee Yun-Hee , Bae Kwang-Hee , Koo Seung-Hoi , Kim Jea-woo , Seong Je Kyung , Hwang Daehee , Song Jaewhan
Published: August 2018

AMP-activated protein kinase (AMPK) plays a key role in controlling energy metabolism in response to physiological and nutritional status. Although AMPK activation has been proposed as a promising molecular target for treating obesity and its related comorbidities, the use of pharmacological AMPK activators has been met with contradictory therapeutic challenges. Here we show a regulatory mechanism for AMPK through its ubiquitination and degradation by the E3 ubiquitin ligase makorin ring finger protein 1 (MKRN1). MKRN1 depletion promotes glucose consumption and suppresses lipid accumulation due to AMPK stabilisation and activation. Accordingly, MKRN1-null mice show chronic AMPK activation in both liver and adipose tissue, resulting in significant suppression of diet-induced metabolic syndrome. We demonstrate also its therapeutic effect by administering shRNA targeting MKRN1 into obese mice that reverses non-alcoholic fatty liver disease. We suggest that ubiquitin-dependent AMPK degradation represents a target therapeutic strategy for metabolic disorders.
Nanomedicines reveal how PBOV1 promotes hepatocellular carcinoma for effective gene therapy
Authors: Guo Yu , Wu Zhiqiang , Shen Shunli , Guo Ruomi , Wang Jing , Wang Weiwei , Zhao Kun , Kuang Ming , Shuai Xintao
Published: August 2018

There exists an urgent medical demand at present to develop therapeutic strategies which can improve the treatment outcome of hepatocellular carcinoma (HCC). Here, we explore the biological functions and clinical significance of PBOV1 in HCC in order to push forward the diagnosis and treatment of HCC. Using theranostical nanomedicines, PBOV1 is verified to be a key oncogene which greatly promotes HCC proliferation, epithelial-to-mesenchymal transition, and stemness by activating the Wnt/β-catenin signaling pathway. Therefore, single-chain antibody for epidermal growth factor receptor (scAb-EGFR)-targeted nanomedicine effectively silencing the PBOV1 gene exhibits potent anticancer effects. In vivo HCC-targeting siRNA delivery mediated by the theranostical nanomedicine remarkably inhibits the tumor growth and metastasis. In addition, the superparamagnetic iron oxide nanocrystals (SPION)-encapsulated nanomedicines possess high MRI detection sensitivity, which endows them with the potential for MRI diagnosis of HCC. This study shows that PBOV1 represents a prognostic biomarker and therapeutic target for HCC.
High entropy oxides for reversible energy storage
Authors: Sarkar Abhishek , Velasco Leonardo , Wang Di , Wang Qingsong , Talasila Gopichand , de Biasi Lea , Kübel Christian , Brezesinski Torsten , Bhattacharya Subramshu S. , Hahn Horst , Breitung Ben
Published: August 2018

In recent years, the concept of entropy stabilization of crystal structures in oxide systems has led to an increased research activity in the field of “high entropy oxides”. These compounds comprise the incorporation of multiple metal cations into single-phase crystal structures and interactions among the various metal cations leading to interesting novel and unexpected properties. Here, we report on the reversible lithium storage properties of the high entropy oxides, the underlying mechanisms governing these properties, and the influence of entropy stabilization on the electrochemical behavior. It is found that the stabilization effect of entropy brings significant benefits for the storage capacity retention of high entropy oxides and greatly improves the cycling stability. Additionally, it is observed that the electrochemical behavior of the high entropy oxides depends on each of the metal cations present, thus providing the opportunity to tailor the electrochemical properties by simply changing the elemental composition.
Lamin B1 mapping reveals the existence of dynamic and functional euchromatin lamin B1 domains
Authors: Pascual-Reguant Laura , Blanco Enrique , Galan Silvia , Le Dily François , Cuartero Yasmina , Serra-Bardenys Gemma , Di Carlo Valerio , Iturbide Ane , Cebrià-Costa Joan Pau , Nonell Lara , de Herreros Antonio García , Di Croce Luciano , Marti-Renom Marc A. , Peiró Sandra
Published: August 2018

Lamins (A/C and B) are major constituents of the nuclear lamina (NL). Structurally conserved lamina-associated domains (LADs) are formed by genomic regions that contact the NL. Lamins are also found in the nucleoplasm, with a yet unknown function. Here we map the genome-wide localization of lamin B1 in an euchromatin-enriched fraction of the mouse genome and follow its dynamics during the epithelial-to-mesenchymal transition (EMT). Lamin B1 associates with actively expressed and open euchromatin regions, forming dynamic euchromatin lamin B1-associated domains (eLADs) of about 0.3 Mb. Hi-C data link eLADs to the 3D organization of the mouse genome during EMT and correlate lamin B1 enrichment at topologically associating domain (TAD) borders with increased border strength. Having reduced levels of lamin B1 alters the EMT transcriptional signature and compromises the acquisition of mesenchymal traits. Thus, during EMT, the process of genome reorganization in mouse involves dynamic changes in eLADs.
De novo targeting to the cytoplasmic and luminal side of bacterial microcompartments
Authors: Lee Matthew J. , Mantell Judith , Brown Ian R. , Fletcher Jordan M. , Verkade Paul , Pickersgill Richard W. , Woolfson Derek N. , Frank Stefanie , Warren Martin J.
Published: August 2018

Bacterial microcompartments, BMCs, are proteinaceous organelles that encase a specific metabolic pathway within a semi-permeable protein shell. Short encapsulation peptides can direct cargo proteins to the lumen of the compartments. However, the fusion of such peptides to non-native proteins does not guarantee encapsulation and often causes aggregation. Here, we report an approach for targeting recombinant proteins to BMCs that utilizes specific de novo coiled-coil protein–protein interactions. Attachment of one coiled-coil module to PduA (a component of the BMC shell) allows targeting of a fluorescent protein fused to a cognate coiled-coil partner. This interaction takes place on the outer surface of the BMC. The redesign of PduA to generate an N-terminus on the luminal side of the BMC results in intact compartments to which proteins can still be targeted via the designed coiled-coil system. This study provides a strategy to display proteins on the surface or within the lumen of the BMCs.
Intertidal exposure favors the soft-studded armor of adaptive mussel coatings
Authors: Monnier Christophe A. , DeMartini Daniel G. , Waite J. Herbert
Published: August 2018

The mussel cuticle, a thin layer that shields byssal threads from environmental exposure, is a model among high-performance coatings for being both hard and hyper-extensible. However, despite avid interest in translating its features into an engineered material, the mechanisms underlying this performance are manifold and incompletely understood. To deepen our understanding of this biomaterial, we explore here the ultrastructural, scratch-resistant, and mechanical features at the submicrometer scale and relate our observations to individual cuticular components. These investigations show that cuticle nanomechanics are governed by granular microinclusions/nanoinclusions, which, contrary to previous interpretations, are three-fold softer than the surrounding matrix. This adaptation, which is found across several related mussel species, is linked to the level of hydration and presumed to maintain bulk performance during tidal exposures. Given the interest in implementing transfer of biological principles to modern materials, these findings may have noteworthy implications for the design of durable synthetic coatings.