bluuebunny/crossref_metadata_2025 huggingface dataset:
Fluorine and chlorine in apatites, micas, and amphiboles of layered trap intrusions of the Siberian Platform
Authors: Ryabov V.V. , Simonov O.N. , Snisar S.G.
Published: April 2018

Geochemistry of chlorine and fluorine in apatites, micas, and amphiboles in rocks from eight intrusive complexes of the Siberian Platform has been first studied on the basis of new factual and analytical data (more than 1000 analyses). The main attention is focused on minerals from layered intrusions. Most apatites show F > Cl; the maximum contents of halogens are specific to chlorapatite (6.97 wt.% Cl) and fluorapatite (6.04 wt.% F). The total f value (f = Fe/(Fe + Mg), at.%) of femic minerals varies from 2 to 98 at.% in micas and from 22 to 95 at.% in amphiboles. The Cl–f and F–f trends show an increase in the Cl content and a decrease in the F content in the minerals with increasing f. Chlorine clearly exhibits ferrophilic properties, and fluorine has magnesiophilic properties. The halogen-richest minerals are fluorophlogopite (F = 7.06 wt.%, f = 7 at.%), chlorannite (Cl = 6.30 wt.%, f = 89 at.%), and chloroferrihastingsite (Cl = 5.22 wt.%, f = 90 at.%). Coexisting micas and amphiboles in the rocks are close in f value, but the micas are richer in Cl than the amphiboles. We assume that the halogen-containing minerals crystallized at the high pressure of halogen–hydrocarbon fluids at the levels of the MW, IW, and QIF buffers. The reducing conditions of the magmatism process are also evidenced by the presence of graphite and native metals in the rocks. The similarity of the Cl–f and F–f trends of micas and amphiboles from different intrusive complexes indicates the same mechanisms of the melt differentiation and mineral crystallization.
Intracranial Electroencephalographic Monitoring: From Subdural to Depth Electrodes
Authors: Joswig Holger , Steven David A. , Parrent Andrew G. , MacDougall Keith W. , Mirsattari Seyed M. , McLachlan Richard S. , Diosy David C. , Burneo Jorge G.
Published: April 2018

At the London Health Sciences Centre Epilepsy Program, stereotactically implanted depth electrodes have largely replaced subdural electrodes in the presurgical investigation of patients with drug-resistant epilepsy over the past 4 years. The rationale for this paradigm shift was more experience with, and improved surgical techniques for, stereoelectroencephalography, a possible lower-risk profile for depth electrodes, better patient tolerability, shorter operative time, as well as increased recognition of potential surgical targets that are not accessible to subdural electrodes.
Spreading dynamics and contact angle of completely wetting volatile drops
Authors: Jambon-Puillet Etienne , Carrier Odile , Shahidzadeh Noushine , Brutin David , Eggers Jens , Bonn Daniel
Published: April 2018

The spreading of evaporating drops without a pinned contact line is studied experimentally and theoretically, measuring the radius$R(t)$of completely wetting alkane drops of different volatility on glass. Initially the drop spreads ($R$increases), then owing to evaporation reverses direction and recedes with an almost constant non-zero contact angle$\unicode[STIX]{x1D703}\propto \unicode[STIX]{x1D6FD}^{1/3}$, where$\unicode[STIX]{x1D6FD}$measures the rate of evaporation; eventually the drop vanishes at a finite-time singularity. Our theory, based on a first-principles hydrodynamic description, well reproduces the dynamics of$R$and the value of$\unicode[STIX]{x1D703}$during retraction.
Successive bifurcations in a fully three-dimensional open cavity flow
Authors: Picella F. , Loiseau J.-Ch. , Lusseyran F. , Robinet J.-Ch. , Cherubini S. , Pastur L.
Published: April 2018

The transition to unsteadiness of a three-dimensional open cavity flow is investigated using the joint application of direct numerical simulations and fully three-dimensional linear stability analyses, providing a clear understanding of the first two bifurcations occurring in the flow. The first bifurcation is characterized by the emergence of Taylor–Görtler-like vortices resulting from a centrifugal instability of the primary vortex core. Further increasing the Reynolds number eventually triggers self-sustained periodic oscillations of the flow in the vicinity of the spanwise end walls of the cavity. This secondary instability causes the emergence of a new set of Taylor–Görtler vortices experiencing a spanwise drift directed toward the spanwise end walls of the cavity. While a two-dimensional stability analysis would fail to capture this secondary instability due to the neglect of the lateral walls, it is the first time to our knowledge that this drifting of the vortices can be entirely characterized by a three-dimensional linear stability analysis of the flow. Good agreements with experimental observations and measurements strongly support our claim that the initial stages of the transition to turbulence of three-dimensional open cavity flows are solely governed by modal instabilities.
Mean shear versus orientation isotropy: effects on inertialess spheroids’ rotation mode in wall turbulence
Authors: Yang Kun , Zhao Lihao , Andersson Helge I.
Published: April 2018

The orientation of spheroidal particles dispersed in a fluid flow is known to influence the particles’ rotation mode. Rod-like and disk-like particles orient themselves differently and accordingly also rotate differently. In order to explore the role of the deterministic factors, i.e. mean shear and vorticity anisotropy, on the orientational behaviour of inertialess tracer spheroids, we adopted a purpose-made Couette–Poiseuille flow simulated numerically by Yanget al. (Intl J. Heat Fluid Flow, vol. 63, 2017, pp. 14–27). Typical wall turbulence with streamwise-oriented streaky structures caused by the locally high mean shear rate was observed only at one of the walls. The absence of mean shear at the other wall gave rise to an atypical turbulence field. Over a relatively wide and quasi-homogeneous core region, a modest mean shear rate made the vorticity field anisotropic. In spite of the mean shear, rod-like tracers were spinning and disk-like spheroids were tumbling, just as in homogeneous isotropic turbulence. We explained this phenomenon by the isotropic particle orientation and concluded that zero mean shear is not necessary for rod spinning and disk tumbling. The orientation and rotation of the Lagrangian tracer spheroids near the high shear wall were almost indistinguishable from the well-known behaviour in turbulent channel flows. Near the opposite wall, where the mean shear was negligibly small, disk-like particles aligned preferentially in the wall-normal direction and rotated similarly as in the presence of high shear. Rod-like particles, on the contrary, aligned more randomly and accordingly rotated similarly as in the core region. These observations revealed that the degree of particle orientation anisotropy has a major impact on the particle rotation mode, whereas mean shear, irrespective of the actual shear rate, only plays a secondary role in particle rotation. Deduction of the eigenvectors of the left Cauchy–Green tensor showed that the preferential orientation of the tracer spheroids was caused by the alignment of rods and disks with the strongest Lagrangian stretching and compression directions, respectively. Lagrangian stretching/compression determines the particle orientations and the particle orientation affects the particle rotation mode.
Shear/rotation competition during the roll-up of acoustically excited shear layers
Authors: Ghasemi Abbas , Tuna Burak Ahmet , Li Xianguo
Published: April 2018

Naturally developing and acoustically excited shear layers at the Reynolds numbers $Re_{\unicode[STIX]{x1D703}_{0}}=U\unicode[STIX]{x1D703}_{0}/\unicode[STIX]{x1D708}=85{-}945$ are studied using the hot-wire (HW) anemometry and particle image velocimetry (PIV), with a focus on the shear/rotation competition during the initial Kelvin–Helmholtz (KH) roll-up. Velocity spectra and the spatial linear stability (LST) analysis characterize the fundamental ($f_{n}$) and its subharmonic ($f_{n}/2$) mode interacting due to the vortex pairing. For $276\leqslant Re_{\unicode[STIX]{x1D703}_{0}}\leqslant 780$, the root-mean-square (r.m.s.) of the streamwise turbulence intensity shows a double-peaking phenomenon, i.e. major and minor peaks of the $u_{rms}$ coexist towards the high-speed (HS) and the low-speed (LS) sides, respectively. The single/double-peaked $u_{rms}$ profiles are found to be correlated with the scattered/organized distribution of the shear/rotation, demonstrating a transitioning character with the downstream distance, $Re_{\unicode[STIX]{x1D703}_{0}}$ and the upstream turbulence levels. The rotating vortex cores and the corresponding peripheral shear regions, demonstrate the phase reversal of the velocity fluctuations with respect to the HS and the LS sides. Excitation at $f_{n}$ increases the vortex count by 21 %, advances the location of the first KH roll-up and hence also the minor peak formation location. Due to the enhanced pairing at the $f_{n}/2$ forcing, the vortex count reduces by 23 %. Before merging into the downstream rotation core, the upstream vortex is shifted towards the HS side and the major peak is accordingly augmented. Actuation advances the transition to the nonlinear state, as well as the saturation of the amplification factor. The volumetric topologies of the shear/rotation loops tracked in consecutive phases during the period of the acoustic excitation, separate from the edge and grow in time–space due to the viscous diffusion. The shearing and rotating loops are found to be associated with the thinning (elongation) and expansion (accumulation) of the vorticity, respectively.
Dietary patterns within educational groups and their association with CHD and stroke in the European Prospective Investigation into Cancer and Nutrition-Netherlands cohort
Authors: Biesbroek Sander , Kneepkens Mirjam C. , van den Berg Saskia W. , Fransen Heidi P. , Beulens Joline W. , Peeters Petra H. M. , Boer Jolanda M. A.
Published: April 2018

Higher-educated people often have healthier diets, but it is unclear whether specific dietary patterns exist within educational groups. We therefore aimed to derive dietary patterns in the total population and by educational level and to investigate whether these patterns differed in their composition and associations with the incidence of fatal and non-fatal CHD and stroke. Patterns were derived using principal components analysis in 36 418 participants of the European Prospective Investigation into Cancer and Nutrition-Netherlands cohort. Self-reported educational level was used to create three educational groups. Dietary intake was estimated using a validated semi-quantitative FFQ. Hazard ratios were estimated using Cox Proportional Hazard analysis after a mean follow-up of 16 years. In the three educational groups, similar ‘Western’, ‘prudent’ and ‘traditional’ patterns were derived as in the total population. However, with higher educational level a lower population-derived score for the ‘Western’ and ‘traditional’ patterns and a higher score on the ‘prudent’ pattern were observed. These differences in distribution of the factor scores illustrate the association between education and food consumption. After adjustments, no differences in associations between population-derived dietary patterns and the incidence of CHD or stroke were found between the educational groups (Pinteraction between 0·21 and 0·98). In conclusion, although in general population and educational groups-derived dietary patterns did not differ, small differences between educational groups existed in the consumption of food groups in participants considered adherent to the population-derived patterns (Q4). This did not result in different associations with incident CHD or stroke between educational groups.
High-intensity-exercise-induced intestinal damage is protected by fermented milk supplemented with whey protein, probiotic and pomegranate (Punica granatumL.)
Authors: Chaves Fernanda M. , Baptista Igor L. , Simabuco Fernando M. , Quaresma Paula G. F. , Pena Fabiola L. , Bezerra Rosangela M. N. , Pauli Jose R. , da Cunha Diogo T. , Campos-Ferraz Patricia L. , Antunes Adriane E. C.
Published: April 2018

Here we evaluated the effect of fermented milk supplemented with whey protein (approximately 80 % protein), probiotic (Bifidobacterium animalissubsp.lactisBB12) and pomegranate juice (Punica granatumL.) on the physical performance, intestinal motility and villi structure, inflammatory markers and intestinal microbiota of rats under high-intensity acute exercise. In all, twenty-four Wistar rats were separated into groups: control (Ctrl), supplemented (Supp), exercised (Exe) and exercised and supplemented (Exe+Supp). Rats in the Supp groups received fermented milk during 6 weeks by oral administration. At the end of the supplementation period, the Exe groups were submitted to high-intensity acute exercise on a treadmill. We found that intense acute exercise caused changes in the intestinal villi interspace, changes in the proportion ofLactobacillusspecies and an increase inClostridiumspecies, as well as a decrease in intestinal motility. Supplementation increased intestinal motility, and maintained the intestinal villi interspace and the natural microbiota proportions of the exercised rats. Physical performance was not improved by fermented milk supplementation. We conclude that the fermented milk containing whey protein,B. animalis(BB12) and pomegranate juice can re-establish intestinal microbiota and protect the animals from the undesirable effects of intense acute exercise.
Liftings of Jordan and Super Jordan Planes
Authors: Andruskiewitsch Nicolás , Angiono Iván , Heckenberger István
Published: April 2018

We classify pointed Hopf algebras with finite Gelfand–Kirillov dimension whose infinitesimal braiding has dimension 2 but is not of diagonal type, or equivalently is a block. These Hopf algebras are new and turn out to be liftings of either a Jordan or a super Jordan plane over a nilpotent-by-finite group.
The Anatomy of a Credit Supply Shock: Evidence from an Internal Credit Market
Authors: Liberti José María , Sturgess Jason
Published: April 2018

We investigate how financial contracting interacts with lending-channel effects by tracing the anatomy of a credit supply shock using micro-level data from a multinational bank. Borrowers with stronger lending relationships, higher nonlending revenues, and those that pledge collateral, especially outside assets and real estate, experience less credit rationing. Consistent with a tightening of financing constraints post shock, borrower composition shifts toward larger and less risky firms, and loans exhibit higher collateralization rates. Our analysis highlights the value of relationships and suggests that relationship banking is a channel through which borrowers can mitigate lending-channel effects.
Haemaphysalis cretaceaa nymph of a new species of hard tick in Burmese amber
Authors: Chitimia-Dobler Lidia , Pfeffer Timo , Dunlop Jason A
Published: April 2018

The first fossil potentially assignable to the extant hard tick genusHaemaphysalisCL Koch (1844) (Ixodida: Ixodidae) is described from the Late Cretaceous (ca. 99 Ma) Burmese amber of Myanmar.Haemaphysalis(Alloceraea)cretaceasp. nov. is the oldest and only fossil representative of this genus; living members of which predominantly feed on mammals. Their typical hosts are known since at least the Jurassic and the discovery of a mid-Cretaceous parasite, which might have fed on mammals raises again the question of to what extent ticks are coupled to their (modern) host groups. An inferred Triassic split of Argasidae (soft ticks) into the bird-preferring Argasinae and mammal-preferring Ornithodorinae dates to about the time when dinosaurs (later including birds) and mammaliaforms as potential hosts were emerging. Ixodidae may have split into Prostriata and Metastriata shortly after the end-Permian mass extinction, an event which fundamentally altered the terrestrial vertebrate fauna. Prostriata (the genusIxodes) prefer birds and mammals today, and some may have used groups like cynodonts in the Triassic. Basal metastriate ticks (e.g.Amblyomma) prefer reptiles, but derived metastriates (includingHaemaphysalis) again prefer mammals. Here, we may be looking at a younger (Cretaceous?) shift associated with more recent mammalian radiations.
Host–symbiont–pathogen interactions in blood-feeding parasites: nutrition, immune cross-talk and gene exchange
Authors: Husnik Filip
Published: April 2018

Animals are common hosts of mutualistic, commensal and pathogenic microorganisms. Blood-feeding parasites feed on a diet that is nutritionally unbalanced and thus often rely on symbionts to supplement essential nutrients. However, they are also of medical importance as they can be infected by pathogens such as bacteria, protists or viruses that take advantage of the blood-feeding nutritional strategy for own transmission. Since blood-feeding evolved multiple times independently in diverse animals, it showcases a gradient of host–microbe interactions. While some parasitic lineages are possibly asymbiotic and manage to supplement their diet from other food sources, other lineages are either loosely associated with extracellular gut symbionts or harbour intracellular obligate symbionts that are essential for the host development and reproduction. What is perhaps even more diverse are the pathogenic lineages that infect blood-feeding parasites. This microbial diversity not only puts the host into a complicated situation – distinguishing between microorganisms that can greatly decrease or increase its fitness – but also increases opportunity for horizontal gene transfer to occur in this environment. In this review, I first introduce this diversity of mutualistic and pathogenic microorganisms associated with blood-feeding animals and then focus on patterns in their interactions, particularly nutrition, immune cross-talk and gene exchange.
Assouad dimensions of complementary sets
Authors: García Ignacio , Hare Kathryn , Mendivil Franklin
Published: April 2018

Given a positive, decreasing sequence a, whose sum is L, we consider all the closed subsets of [0, L] such that the lengths of their complementary open intervals are in one-to-one correspondence with the sequence a. The aim of this paper is to investigate the possible values that Assouad-type dimensions can attain for this class of sets. In many cases, the set of attainable values is a closed interval whose endpoints we determine.
A simple model of biofilm growth in a porous medium that accounts for detachment and attachment of suspended biomass and their contribution to substrate degradation
Authors: GAEBLER HARRY J. , EBERL HERMANN J.
Published: April 2018

We derive a macroscopic model for biofilm formation in a porous medium reactor to investigate the role of suspended bacteria on reactor performance. The starting point is the mesoscopic one-dimensional Wanner–Gujer biofilm model. The following processes are included: hydrodynamics and transport of substrate in the reactor, biofilm and suspended bacteria growth in the pore space, attachment of suspended cells to the biofilm, and detachment of biofilm cells. The mesoscopic equations are up-scaled from the biofilm scale to the reactor scale, yielding a stiff system of balance laws, which we study numerically. We find that suspended bacteria and attachment can have a significant effect on biofilm reactor performance.
Ewens Sampling and Invariable Generation
Authors: BRITO GERANDY , FOWLER CHRISTOPHER , JUNGE MATTHEW , LEVY AVI
Published: April 2018

We study the number of random permutations needed to invariably generate the symmetric group Sn when the distribution of cycle counts has the strong α-logarithmic property. The canonical example is the Ewens sampling formula, for which the special case α = 1 corresponds to uniformly random permutations.

For strong α-logarithmic measures and almost every α, we show that precisely ⌈(1−αlog2)−1⌉ permutations are needed to invariably generate Sn with asymptotically positive probability. A corollary is that for many other probability measures on Sn no fixed number of permutations will invariably generate Sn with positive probability. Along the way we generalize classic theorems of Erdős, Tehran, Pyber, Łuczak and Bovey to permutations obtained from the Ewens sampling formula.
Households and heat stress: estimating the distributional consequences of climate change
Authors: Park Jisung , Bangalore Mook , Hallegatte Stephane , Sandhoefner Evan
Published: April 2018

Recent research documents the adverse causal impacts on health and productivity of extreme heat, which will worsen with climate change. In this paper, we assess the current distribution of heat exposure within countries, to explore possible distributional consequences of climate change through temperature. Combining survey data from 690,745 households across 52 countries with spatial data on climate, this paper suggests that the welfare impacts of added heat stress may be regressivewithincountries. We find: (1) a strong negative correlation between household wealth and warmer temperature in many hot countries; (2) a strong positive correlation between household wealth and warmer temperatures in many cold countries; and (3) that poorer individuals are more likely to work in occupations with greater exposure. While our analysis is descriptive rather than causal, our results suggest a larger vulnerability of poor people to heat extremes, and potentially significant distributional and poverty implications of climate change.
Consumption of ultra-processed food and obesity: cross sectional results from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) cohort (2008–2010)
Authors: Silva Fernanda Marcelina , Giatti Luana , de Figueiredo Roberta Carvalho , Molina Maria del Carmen Bisi , de Oliveira Cardoso Letícia , Duncan Bruce Bartholow , Barreto Sandhi Maria
Published: April 2018

Objective

To verify if the intake of ultra-processed foods is associated with higher BMI and waist circumference (WC) among participants of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) cohort.

Design

Cross-sectional analysis of the ELSA-Brasil baseline (2008–2010). Dietary information obtained through an FFQ was classified according to characteristics of food processing (NOVA) and used to estimate the percentage energy contribution from ultra-processed foods (i.e. industrial formulations, elaborated from food processing, synthetic constituents and food additives) to individuals’ total energy intake. BMI and WC and their respective cut-off points served as response variables. Associations were estimated through linear and multinomial logistic regression models, after adjusting for confounders and total energy intake.

Setting

Six Brazilian capital cities, 2008–2010.

Subjects

Active and retired civil servants, aged 35–64 years, from universities and research organizations (n8977).

Results

Ultra-processed foods accounted for 22·7 % of total energy intake. After adjustments, individuals in the fourth quartile of percentage energy contribution from ultra-processed foods presented (β; 95 % CI) a higher BMI (0·80; CI 0·53, 1·07 kg/m2) and WC (1·71; 1·02, 2·40 cm), and higher chances (OR; 95 % CI) of being overweight (1·31; 1·13, 1·51), obese (1·41; 1·18, 1·69) and having significantly increased WC (1·41; 1·20, 1·66), compared with those in the first quartile. All associations suggest a dose–response gradient.

Conclusions

Results indicate the existence of associations between greater energy contribution from ultra-processed foods and higher BMI and WC, which are independent of total energy intake. These findings corroborate public policies designed to reduce the intake of this type of food.
Identifying sociodemographic, programmatic and dietary drivers of anaemia reduction in pregnant Indian women over 10 years
Authors: Chakrabarti Suman , George Nitya , Majumder Moutushi , Raykar Neha , Scott Samuel
Published: April 2018

Objective

Anaemia is a major contributor to the global disease burden and half of pregnant women in India were anaemic in 2016. The aetiology of anaemia is complex, yet anaemia determinants are frequently examined in isolation. We sought to explore how shifts in sociodemographic (wealth, age at pregnancy, education, open defecation, cooking fuel type, household size), programmatic (iron–folic acid tablet consumption, antenatal care visits) and dietary factors (intake of Fe, folic acid, vitamin B12, phytate) predicted changes in anaemia prevalence.

Design

Nutrient levels for eighty-eight food items were multiplied by household consumption of these foods to estimate household-level nutrient supply. A synthetic panel data set was created from two rounds of the District Level Household and Facility Survey (2002–04 and 2012–13) and Household Consumer Expenditures Survey (2004–05 and 2011–12). Ordinary least-squares multivariate regression models were used.

Setting

Districts (n 446) spanning north, north-east, central and south India.

Subjects

Pregnant women aged 15–49 years (n 17 138).

Results

In the model accounting for both non-dietary and dietary factors, increased age at pregnancy (P<0·001), reduced village-level open defecation (P=0·001), consuming more Fe (P<0·001) and folic acid (P=0·018) and less phytate (P=0·002), and urbanization (P=0·015) were associated with anaemia reductions. A 10 mg increase in daily household Fe supply from 2012 levels was associated with a 10 % reduction in anaemia.

Conclusions

Public health interventions to combat anaemia in pregnant women should use a holistic approach, including promotion of delayed marriage, construction and use of toilets, and measures that facilitate adoption of nutrient-rich diets.
‘A Serious House on Serious Earth’: Towards an Understanding of the Church of England’s Inheritance of Buildings
Authors: Carter Benjamin
Published: April 2018

The Church of England is blessed with an extraordinary inheritance of church buildings. However, this inheritance, particularly in rural contexts, is increasingly being viewed as a financial millstone and encumbrance to mission. This article takes issue with the largely ‘functional’ understanding of church buildings which is common place in the Church of England. It will argue that there needs to be a rediscovery of the symbolic and sacramental power of buildings. By reasserting the sacramental and symbolic power of church buildings we can come again to recognize how all church buildings – and not just those blessed with a great history or soaring architecture – exist in part to articulate the ongoing presence and activity of God in creation.
Wideband high-efficiency linearized PA design with reduction in memory effects and IMD3
Authors: Du Xuekun , You Chang Jiang , Zhao Yulong , Li Xiang , Helaoui Mohamed , Cai Jingye , Ghannouchi Fadhel M.
Published: April 2018

An analytical method is proposed to reduce the memory effects and third-order intermodulation distortions for improving the linearity of wideband power amplifier (PA). An excellent linearity can be obtained by reducing the second-harmonic output power levels and reducing the envelope voltage components in the megahertz range. An improved wideband Chebyshev low-pass matching network including the bias network is analyzed and designed to validate the proposed method. The measured results indicate that a wideband high-efficiency linearized PA is realized from 1.35 to 2.45 GHz (fractional bandwidth = 58%) with power added efficiency of 60–78%, power gain of 10.8–12.3 dB, and output power of 40.0–41.2 dBm. For a 20 MHz LTE modulated signal, the adjacent channel leakage ratios (ACLRs) of the proposed PA with digital pre-distortion (DPD) linearization are −55.7 ~ −53.9 dBc across 1.5–2.4 GHz at an average output power of 32.4–33.6 dBm. For a 40 MHz two-carrier LTE modulated signal, the ACLRs of the proposed PA with DPD linearization are −51.1 ~ −48.2 dBc at an average output power of ~30.5 dBm in the frequency range from 1.5 GHz to 2.4 GHz.
Multi-functional DNA nanostructures that puncture and remodel lipid membranes into hybrid materials
Authors: Birkholz Oliver , Burns Jonathan R. , Richter Christian P. , Psathaki Olympia E. , Howorka Stefan , Piehler Jacob
Published: April 2018

Synthetically replicating key biological processes requires the ability to puncture lipid bilayer membranes and to remodel their shape. Recently developed artificial DNA nanopores are one possible synthetic route due to their ease of fabrication. However, an unresolved fundamental question is how DNA nanopores bind to and dynamically interact with lipid bilayers. Here we use single-molecule fluorescence microscopy to establish that DNA nanopores carrying cholesterol anchors insert via a two-step mechanism into membranes. Nanopores are furthermore shown to locally cluster and remodel membranes into nanoscale protrusions. Most strikingly, the DNA pores can function as cytoskeletal components by stabilizing autonomously formed lipid nanotubes. The combination of membrane puncturing and remodeling activity can be attributed to the DNA pores’ tunable transition between two orientations to either span or co-align with the lipid bilayer. This insight is expected to catalyze the development of future functional nanodevices relevant in synthetic biology and nanobiotechnology.
Mutation hotspots at CTCF binding sites coupled to chromosomal instability in gastrointestinal cancers
Authors: Guo Yu Amanda , Chang Mei Mei , Huang Weitai , Ooi Wen Fong , Xing Manjie , Tan Patrick , Skanderup Anders Jacobsen
Published: April 2018

Tissue-specific driver mutations in non-coding genomic regions remain undefined for most cancer types. Here, we unbiasedly analyze 212 gastric cancer (GC) whole genomes to identify recurrently mutated non-coding regions in GC. Applying comprehensive statistical approaches to accurately model background mutational processes, we observe significant enrichment of non-coding indels (insertions/deletions) in three gastric lineage-specific genes. We further identify 34 mutation hotspots, of which 11 overlap CTCF binding sites (CBSs). These CBS hotspots remain significant even after controlling for a genome-wide elevated mutation rate at CBSs. In 3 out of 4 tested CBS hotspots, mutations are nominally associated with expression change of neighboring genes. CBS hotspot mutations are enriched in tumors showing chromosomal instability, co-occur with neighboring chromosomal aberrations, and are common in gastric (25%) and colorectal (19%) tumors but rare in other cancer types. Mutational disruption of specific CBSs may thus represent a tissue-specific mechanism of tumorigenesis conserved across gastrointestinal cancers.
Flexible and ultra-lightweight polymer membrane lasers
Authors: Karl Markus , Glackin James M. E. , Schubert Marcel , Kronenberg Nils M. , Turnbull Graham A. , Samuel Ifor D. W. , Gather Malte C.
Published: April 2018

Organic semiconductors enable the fabrication of a range of lightweight and mechanically flexible optoelectronic devices. Most organic semiconductor lasers, however, have remained rigid until now, predominantly due to the need for a support substrate. Here, we use a simple fabrication process to make membrane-based, substrate-less and extremely thin (<500 nm) organic distributed feedback lasers that offer ultralow-weight (m/A<0.5 gm−2) and excellent mechanical flexibility. We show operation of the lasers as free-standing membranes and transfer them onto other substrates, e.g. a banknote, where the unique lasing spectrum is readily read out and used as security feature. The pump thresholds and emission intensity of our membrane lasers are well within the permissible exposures for ocular safety and we demonstrate integration on contact lenses as wearable security tags.
Histone H2AX deficiency causes neurobehavioral deficits and impaired redox homeostasis
Authors: Weyemi Urbain , Paul Bindu D. , Snowman Adele M. , Jailwala Parthav , Nussenzweig Andre , Bonner William M. , Snyder Solomon H.
Published: April 2018

ATM drives DNA repair by phosphorylating the histone variant H2AX. While ATM mutations elicit prominent neurobehavioral phenotypes, neural roles for H2AX have been elusive. We report impaired motor learning and balance in H2AX-deficient mice. Mitigation of reactive oxygen species (ROS) with N-acetylcysteine (NAC) reverses the behavioral deficits. Mouse embryonic fibroblasts deficient for H2AX exhibit increased ROS production and failure to activate the antioxidant response pathway controlled by the transcription factor NRF2. The NRF2 targets GCLC and NQO1 are depleted in the striatum of H2AX knockouts, one of the regions most vulnerable to ROS-mediated damage. These findings establish a role for ROS in the behavioral deficits of H2AX knockout mice and reveal a physiologic function of H2AX in mediating influences of oxidative stress on NRF2-transcriptional targets and behavior.
Photon antibunching in a cluster of giant CdSe/CdS nanocrystals
Authors: Lv Bihu , Zhang Huichao , Wang Lipeng , Zhang Chunfeng , Wang Xiaoyong , Zhang Jiayu , Xiao Min
Published: April 2018

When closely packed into a high-density film, semiconductor nanocrystals (NCs) can interact with each other to yield collective optical behaviours, which are normally difficult to characterize due to the ensemble average effect. Here we synthesized semiconductor NC clusters and performed single-particle spectroscopic measurements to probe the electronic couplings of several giant CdSe/CdS NCs contained in one cluster with nanometer-scale separations. Such a single cluster exhibits multiple emission peaks at the cryogenic temperature with nearly identical photoluminescence decay dynamics, suggesting that the Förster-type energy transfer does not occur among the composing NCs. Surprisingly, strong photon antibunching is still observed from a single cluster, which can be attributed to the Auger annihilation of photo-excited excitons from different NCs. The isolation of several nearby NCs interacting with the above novel mechanism has marked a solid progress towards a full understanding and an efficient control of the operation parameters in NC-based optoelectronic devices.
TRPV1 SUMOylation regulates nociceptive signaling in models of inflammatory pain
Authors: Wang Yan , Gao Yingwei , Tian Quan , Deng Qi , Wang Yangbo , Zhou Tian , Liu Qiang , Mei Kaidi , Wang Yingping , Liu Huiqing , Ma Ruining , Ding Yuqiang , Rong Weifang , Cheng Jinke , Yao Jing , Xu Tian-Le , Zhu Michael X. , Li Yong
Published: April 2018

Although TRPV1 channels represent a key player of noxious heat sensation, the precise mechanisms for thermal hyperalgesia remain unknown. We report here that conditional knockout of deSUMOylation enzyme, SENP1, in mouse dorsal root ganglion (DRG) neurons exacerbated thermal hyperalgesia in both carrageenan- and Complete Freund’s adjuvant-induced inflammation models. TRPV1 is SUMOylated at a C-terminal Lys residue (K822), which specifically enhances the channel sensitivity to stimulation by heat, but not capsaicin, protons or voltage. TRPV1 SUMOylation is decreased by SENP1 but upregulated upon peripheral inflammation. More importantly, the reduced ability of TRPV1 knockout mice to develop inflammatory thermal hyperalgesia was rescued by viral infection of lumbar 3/4 DRG neurons of wild-type TRPV1, but not its SUMOylation-deficient mutant, K822R. These data suggest that TRPV1 SUMOylation is essential for the development of inflammatory thermal hyperalgesia, through a mechanism that involves sensitization of the channel response specifically to thermal stimulation.
Nuclear receptor NR2F6 inhibition potentiates responses to PD-L1/PD-1 cancer immune checkpoint blockade
Authors: Klepsch Victoria , Hermann-Kleiter Natascha , Do-Dinh Patricia , Jakic Bojana , Offermann Anne , Efremova Mirjana , Sopper Sieghart , Rieder Dietmar , Krogsdam Anne , Gamerith Gabriele , Perner Sven , Tzankov Alexandar , Trajanoski Zlatko , Wolf Dominik , Baier Gottfried
Published: April 2018

Analyzing mouse tumor models in vivo, human T cells ex vivo, and human lung cancer samples, we provide direct evidence that NR2F6 acts as an immune checkpoint. Genetic ablation of Nr2f6, particularly in combination with established cancer immune checkpoint blockade, efficiently delays tumor progression and improves survival in experimental mouse models. The target genes deregulated in intratumoral T lymphocytes upon genetic ablation of Nr2f6 alone or together with PD-L1 blockade reveal multiple advantageous transcriptional alterations. Acute Nr2f6 silencing in both mouse and human T cells induces hyper-responsiveness that establishes a non-redundant T-cell-inhibitory function of NR2F6. NR2F6 protein expression in T-cell-infiltrating human NSCLC is upregulated in 54% of the cases (n = 303) and significantly correlates with PD-1 and CTLA-4 expression. Our data define NR2F6 as an intracellular immune checkpoint that suppresses adaptive anti-cancer immune responses and set the stage for clinical validation of targeting NR2F6 for next-generation immuno-oncological regimens.
Screened moments and extrinsic in-gap states in samarium hexaboride
Authors: Fuhrman W. T. , Chamorro J. R. , Alekseev P. A. , Mignot J.-M. , Keller T. , Rodriguez-Rivera J. A. , Qiu Y. , Nikolić P. , McQueen T. M. , Broholm C. L.
Published: April 2018

Samarium hexaboride (SmB6) is a Kondo insulator, with a narrow gap due to hybridization between localized and conduction electrons. Despite being an insulator, many samples show metal-like properties. Rare-earth purification is exceedingly difficult, and nominally pure samples may contain 2% or more of impurities. Here to determine the effects of rare-earth doping on SmB6, we synthesized and probed a series of gadolinium-doped samples. We found a relationship between specific heat and impurity moment screening which scales systematically. Consistent with this finding, our neutron scattering experiments of a high purity sample of doubly isotopic 154Sm11B6 show no intrinsic excitations below the well-established 13 meV spin-exciton. The result of introducing impurities into a Kondo insulator is incompletely understood, but it is clear from our measurements that there is a systematic relationship between rare-earth impurities and metal-like properties in SmB6.
Stabilizing ultrasmall Au clusters for enhanced photoredox catalysis
Authors: Weng Bo , Lu Kang-Qiang , Tang Zichao , Chen Hao Ming , Xu Yi-Jun
Published: April 2018

Recently, loading ligand-protected gold (Au) clusters as visible light photosensitizers onto various supports for photoredox catalysis has attracted considerable attention. However, the efficient control of long-term photostability of Au clusters on the metal-support interface remains challenging. Herein, we report a simple and efficient method for enhancing the photostability of glutathione-protected Au clusters (Au GSH clusters) loaded on the surface of SiO2 sphere by utilizing multifunctional branched poly-ethylenimine (BPEI) as a surface charge modifying, reducing and stabilizing agent. The sequential coating of thickness controlled TiO2 shells can further significantly improve the photocatalytic efficiency, while such structurally designed core-shell SiO2-Au GSH clusters-BPEI@TiO2 composites maintain high photostability during longtime light illumination conditions. This joint strategy via interfacial modification and composition engineering provides a facile guideline for stabilizing ultrasmall Au clusters and rational design of Au clusters-based composites with improved activity toward targeting applications in photoredox catalysis.
The formation of perovskite multiple quantum well structures for high performance light-emitting diodes
Authors: Sun Yan , Zhang Li , Wang Nana , Zhang Shuting , Cao Yu , Miao Yanfeng , Xu Mengmeng , Zhang Hao , Li Hai , Yi Chang , Wang Jianpu , Huang Wei
Published: April 2018

Recent works showed that high efficient perovskite light-emitting diodes can be achieved from solution-processed, self-organized multiple quantum wells (MQWs) with an energy cascade. We investigate how the mixing of QWs with different band gaps can affect the perovskite LED device performance. We find that the annealing process can significantly affect the constitution of the MQWs films, where the dominant phase can evolve from large band gap QWs to small band gap QWs. The optimal constitution for LED application lies in a transition point of small-n QWs dominant phase to large-n QWs dominant phase, when the MQW film presents highest photoluminescence while still remains uniform film morphology.
Comprehensive comparison of polysaccharides from Ganoderma lucidum and G. sinense: chemical, antitumor, immunomodulating and gut-microbiota modulatory properties
Authors: Li Li-Feng , Liu Hong-Bing , Zhang Quan-Wei , Li Zhi-Peng , Wong Tin-Long , Fung Hau-Yee , Zhang Ji-Xia , Bai Su-Ping , Lu Ai-Ping , Han Quan-Bin
Published: April 2018

Both Ganoderma lucidum (GL) and G. sinense (GS) are used as Lingzhi in China. Their functions are assumed to mainly derive from triterpenes and polysaccharides; however, the two species have very different triterpenes profiles, if this was the case, then the bioactivity of these two species should differ. Instead, could the polysaccharides be similar, contributing to the shared therapeutic basis? In this study, two main polysaccharide fractions from different batches of GL and GS were systematically compared by a series of chemical and biological experiments. The results showed that the polysaccharides from two species shared the same structural features in terms of mono-/oligo-saccharide profiles, molecular size, sugar linkages, and IR/NMR spectra. In addition, these polysaccharides showed similar tumor-suppressive activity in mice. Further study on RAW264.7 cells indicated that these polysaccharides exhibited similar inducing effects to macrophages, as evaluated in the phagocytosis function, NO/cytokines production, inhibition against the viability and migration of cancer cells. Mechanistic investigation revealed the identical activation via TLR-4 related MAPK/NF-κB signaling pathway and gut-microbiota modulatory effects. In summary, GL and GS polysaccharides presented similar chemical features, antitumor/immunomodulating activities and mechanism; this establishes polysaccharides as the active principles and supports the official use of both species as Lingzhi.
Author Correction: Localization and function of neurosecretory protein GM, a novel small secretory protein, in the chicken hypothalamus
Authors: Shikano Kenshiro , Bessho Yuki , Kato Masaki , Iwakoshi-Ukena Eiko , Taniuchi Shusuke , Furumitsu Megumi , Tachibana Tetsuya , Bentley George E. , Kriegsfeld Lance J. , Ukena Kazuyoshi
Published: April 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Author Correction: Disposition of a Glucose Load into Hepatic Glycogen by Direct and Indirect Pathways in Juvenile Seabass and Seabream
Authors: Rito João , Viegas Ivan , Pardal Miguel A. , Metón Isidoro , Baanante Isabel V. , Jones John G.
Published: April 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Publisher Correction: Virtual Genome Walking across the 32 Gb Ambystoma mexicanum genome; assembling gene models and intronic sequence
Authors: Evans Teri , Johnson Andrew D. , Loose Matthew
Published: April 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Cryopreservation of Fish Spermatogonial Cells: The Future of Natural History Collections
Authors: Hagedorn Mary M. , Daly Jonathan P. , Carter Virginia L. , Cole Kathleen S. , Jaafar Zeehan , Lager Claire V. A. , Parenti Lynne R.
Published: April 2018

As global biodiversity declines, the value of biological collections increases. Cryopreserved diploid spermatogonial cells meet two goals: to yield high-quality molecular sequence data; and to regenerate new individuals, hence potentially countering species extinction. Cryopreserved spermatogonial cells that allow for such mitigative measures are not currently in natural history museum collections because there are no standard protocols to collect them. Vertebrate specimens, especially fishes, are traditionally formalin-fixed and alcohol-preserved which makes them ideal for morphological studies and as museum vouchers, but inadequate for molecular sequence data. Molecular studies of fishes routinely use tissues preserved in ethanol; yet tissues preserved in this way may yield degraded sequences over time. As an alternative to tissue fixation methods, we assessed and compared previously published cryopreservation methods by gating and counting fish testicular cells with flow cytometry to identify presumptive spermatogonia A-type cells. Here we describe a protocol to cryopreserve tissues that yields a high percentage of viable spermatogonial cells from the testes of Asterropteryx semipunctata, a marine goby. Material cryopreserved using this protocol represents the first frozen and post-thaw viable spermatogonial cells of fishes archived in a natural history museum to provide better quality material for re-derivation of species and DNA preservation and analysis.
Tau Antibody Structure Reveals a Molecular Switch Defining a Pathological Conformation of the Tau Protein
Authors: Chukwu Jessica E. , Pedersen Jan T. , Pedersen Lars Ø. , Volbracht Christiane , Sigurdsson Einar M. , Kong Xiang-Peng
Published: April 2018

Tau antibodies have shown therapeutic potential for Alzheimer’s disease and several are in clinical trials. As a microtubule-associated protein, tau relies on dynamic phosphorylation for its normal functions. In tauopathies, it becomes hyperphosphorylated and aggregates into toxic assemblies, which collectively lead to neurodegeneration. Of the phospho-epitopes, the region around Ser396 has received particular attention because of its prominence and stability in tauopathies. Here we report the first structure of a monoclonal tau antibody in complex with the pathologically important phospho-Ser396 residue. Its binding region reveals tau residues Tyr394 to phospho-Ser396 stabilized in a β-strand conformation that is coordinated by a phospho-specific antigen binding site. These details highlight a molecular switch that defines this prominent conformation of tau and ways to target it. Overall, the structure of the antibody-antigen complex clarifies why certain phosphorylation sites in tau are more closely linked to neurodegeneration than others.
Clinical characteristics and risk factors for overlapping rheumatoid arthritis and Sjögren’s syndrome
Authors: Yang Huaxia , Bian Sainan , Chen Hua , Wang Li , Zhao Lidan , Zhang Xuan , Zhao Yan , Zeng Xiaofeng , Zhang Fengchun
Published: April 2018

This study investigated the clinical characteristics and risk factors for overlapping rheumatoid arthritis and Sjögren’s syndrome (RA/SS). Patients with RA/SS in Peking Union Medical College Hospital from January 2012 to January 2017 were retrospectively analysed and compared to those of sex- and age–matched RA or SS controls. Logistic regression analysis was used to identify risk factors. Altogether, 105 consecutive patients with RA/SS were enrolled. Ninety-seven (92.4%) of them were female, with a mean age of 51.5 ± 13.3 years or 45.2 ± 14.7years at the diagnosis of SS or RA, respectively. In addition to arthritis and Sicca symptom, patients with RA/SS had more visceral involvements including interstitial lung disease (ILD), and haematologic involvement, and received more glucocorticoid treatments than controls (p < 0.05). RA-onset, simultaneous-onset and SS-onset patients had significant differences in age at RA diagnosis, fever and thrombocytopenia (p < 0.05). Multivariate logistic analysis indicated that arthritis (OR = 44.804), rheumatoid factor (RF) (OR = 5.973), and anti-CCP (OR = 2.545) were independent risk factors for SS overlapping with RA. Xerostomia (OR = 3.960), ILD (OR = 6.210), and anti-SSA (OR = 24.640) were independent predictors of RA overlapping with SS. RA/SS patients have more visceral involvements. Our findings highlight the roles of arthritis/RF/anti-CCP and xerostomia/ILD/anti-SSA in the development of this overlapping disease.