bluuebunny/crossref_metadata_2025 huggingface dataset:
On the Ginzburg-Landau energy with weight
Authors: Lefter Cătălin , Rădulescu Vicenţiu D.
Published: February 2017

This paper gives a solution to an open problem raised by Bethuel, Brezis and Hélein. We study the Ginzburg–Landau energy with weight. We find the expression of the renormalized energy and we show that the finite configuration of singularities of the limit is a minimum point of this functional. We find a vanishing gradient type property and then we obtain the renormalized energy by Bethuel, Brezis and Hélein’s shrinking holes method.

Ce travail donne la solution d’un problème ouvert de Bethuel, Brezis et Hélein. On étudie l’énergie de Ginzburg–Landau avec poids. Nous trouvons l’expression de l’énergie renormalisée et on prouve que la configuration finie des singularités de la limite est un point de minimum pour cette fonctionnelle. Nous montrons une propriété du type « vanishing gradient » et on obtient ensuite l’énergie renormalisée avec la méthode « shrinking holes » de Bethuel, Brezis et Hélein.
Multiplicity of positive and nodal solutions for nonlinear elliptic problems in $ℝ^N$
Authors: Cao Daomin , Noussair Ezzat S.
Published: February 2017

We are concerned with the multiplicity of positive and nodal solutions of

\begin{cases}
−\mathrm{\Delta }u + \mu u = Q(x)|u|^{p−2}u &\text{in }\: ℝ^{N} \\
u \in H^{1}(\mathbf{ℝ}^{N})
\end{cases}

where

2 < p < \frac{2N}{N−2}

,

N ≥ 3

,

μ > 0

,

Q ∈ C(ℝ^N)

and

Q(x) ≥ 0

for

x ∈ ℝ^N

. We show how the “shape” of the graph of

Q(x)

affects the number of both positive and nodal solutions.
On the uniqueness of solutions of the homogeneous curvature equations
Authors: Cranny Timothy R.
Published: February 2017

We prove that viscosity solutions of the degenerate prescribed curvature equation

F[u] = F(κ_1,\ldots, κ_n) ≡ 0

in

Ω

,

u = g

on

∂Ω

are unique for a broad class of differential operators

F

.
On critical exponents for the heat equation with a nonlinear boundary condition
Authors: Bei Hu , Yin Hong-Ming
Published: February 2017

In this paper we consider the heat equation

u_t = ∆u

in a unbounded domain

Ω ⊂ R^N

with a Neumann boundary condition

u_\nu = u^p

, where

p > 1

and

\nu

is the exterior unit normal on

∂Ω

. It is shown for various type of domains that there exists a critical number

p_c (Ω) ≥ 1

, such that all of positive solutions blow up in a finite time when

p\in (1, p_c]

while there exist positive global solutions if

p > p_c

and initial data are small.
On the existence of homoclinic solutions for almost periodic second order systems
Authors: Serra Enrico , Tarallo Massimo , Terracini Susanna
Published: February 2017

In this paper we prove the existence of at least one homoclinic solution for a second order Lagrangian system, where the potential is an almost periodic function of time. This result generalizes existence theorems known to hold when the dependence on time of the potential is periodic. The method is of a variational nature, solutions being found as critical points of a suitable functional. The absence of a group of symmetries for which the functional is invariant (as in the case of periodic potentials) is replaced by the study of problems “at infinity” and a suitable use of a property introduced by E. Séré.

Dans cet article on démontre l’existence d’une solution homocline pour un système Lagrangien du deuxième ordre où le potentiel dépend du temps d’une façon quasi périodique. Ce résultat généralise le cas où le potentiel est une fonction périodique du temps. La méthode utilisée est variationnelle, les solutions étant trouvées comme points critiques d’une fonctionnelle. L’absence d’un groupe de symétries pour lequel la fonctionnelle est invariante (comme dans le cas des potentiels périodiques) est remplacée par l’étude des points critiques « à l’infini » et par une propriété introduite par E. Séré.
FORAGING MODELS, NICHE CONSTRUCTION, AND THE EASTERN AGRICULTURAL COMPLEX
Authors: Zeanah David W.
Published: February 2017

Some proponents of niche construction challenge the validity of optimality models for investigating agricultural origins, but offer no alternative strategy for understanding the economic context of human foraging decisions. They refer to the Eastern Agricultural Complex as an example of how seed cultivation can result from resource enhancement rather than population-induced resource depression, contradicting a prediction inferred from the prey choice model. Low-return seed cultigens were harvested in environments offering more highly ranked hickory nuts in abundance, apparently supporting their interpretation. A marginal value model demonstrates that in years of low mast yield, foragers could more profitably fill food stores from nearby seed plots than from distant hickory trees. Cultivating seeds would have been economically worthwhile when population circumscription constrained mobility, consistent with trends indicating regional population growth. Surges in walnut shell relative to small seeds are also consistent with the model, suggesting that foragers intensified their use of local, anthropogenic vegetation communities as populations grew, stimulating development of horticultural economies. This illustrates the value of foraging models used in conjunction with niche construction for investigating agricultural origins, particularly when model predictions initially fail to accord with archaeological evidence.
TREE-RING DATES AND NAVAJO SETTLEMENT PATTERNS IN ARIZONA
Authors: Colwell Chip , Ferguson T. J.
Published: February 2017

The historical timing and movement of Navajo communities in the U.S. Southwest continue to be key, but unresolved, issues. This paper analyzes tree-ring data to consider initial Navajo settlement patterns in the Little Colorado River watershed, Black Mesa, and nearby regions in northern Arizona. We are critical of previous studies that deem all tree-ring dates to be equally valid, so we present a new approach to systematically identify potential early Navajo sites. After analyzing hundreds of tree-ring specimens from 774 sites, we conclude that dendrochronological evidence offers moderate-to-high confidence that 18 Navajo sites in the study area were settled prior to 1882. These dendrochronological data support the hypothesis of a westward Navajo migration from the Dinétah, reaching Black Mesa in Arizona about 1840, other areas north and east of the Hopi Mesas in the 1850s, and land west of Hopi in the 1870s after the release of Navajos from Fort Sumner in 1868.
Conserving Atlantic salmon ‘after nature’ on Newfoundland's Gander river
Authors: DANIELS JENNIFER , MATHER CHARLES
Published: February 2017

This paper examines the history of Atlantic salmon conservation in Eastern Canada, with a specific emphasis on Newfoundland's Gander river. Conservation efforts for this iconic species begin in the late 1800s and continue through to the contemporary period. Our work is framed by current debates on the Anthropocene and its implications for environmental conservation. We identify two different historical phases in salmon conservation associated with different socio-ecological assemblages, and different conceptualizations of nature. Drawing on oral histories, we also reveal a third human–salmon entanglement associated with what we call the ‘wilful salmon’. The wilful salmon fits uneasily with the idea of conservation, and in some ways it seems contrary to conservation efforts. It is, nonetheless, a legitimate fish that deserves to be considered and evaluated in a world ‘after nature’.
Utility of 4D Flow mapping in Eisenmenger syndrome with pulmonary atresia
Authors: Romeih Soha , Aguib Heba , Yacoub Magdi
Published: February 2017

Management of patients with Eisenmenger syndrome with pulmonary atresia is challenging because of the complexity of the structure–function relationship of the components of the syndrome. Multi-modality imaging including cardiac magnetic resonance (CMR) 4D Flow offers unprecedented opportunities to unravel, at least in part, some of these components, and thus help in the management of these patients. In this study, we describe the use of these integrated methods with particular reference to CMR 4D Flow in a patient with Eisenmenger syndrome and pulmonary atresia and outline both the utility and the limitations. A comprehensive cardiac magnetic resonance (CMR) 4D Flow analysis was performed preoperatively and postoperatively, during peak systole, late systole, early diastole, and late diastole. The focus of the present study was to investigate the pattern of flow and dynamic changes at different levels of the aorta, as well as in the duct and the pulmonary arteries. Preoperatively, a right-handed helix and a vortex were observed in the dilated ascending aorta, and the duct flow was mainly dependent on reverse, upstream flow from the descending aorta, distal to the duct, during diastole, denoting low pulmonary vascular capacitance. Following repair, the flow in the ascending aorta and the descending aorta changed markedly. These changes included both timing and intensity of the right-handed helix, as well as the vortex in the ascending aorta. The significance of the observed changes in flow pattern and their influence on wall structure and function are discussed. Our study demonstrates the extremely powerful potential of CMR 4D Flow in the management of complex congenital anomalies.
Training in paediatric cardiac surgery: the history and role of training in a different country and even overseas
Authors: Elliott Martin J.
Published: February 2017

This paper presents a personal perspective on the value of training overseas in paediatric cardiac surgery. From personal experience and observation, I argue that travel does indeed broaden the mind and placing artificial constraints on movement of trainees is a negative move. We need to work with others, in other cultures to become rounded human beings. And to be an empathetic surgeon, you need to be a rounded human being.
Big Data and paediatric cardiovascular disease in the era of transparency in healthcare
Authors: Asante-Korang Alfred , Jacobs Jeffrey P
Published: February 2017

The objectives of this review were to discuss the potential impact of Big Data analytics in paediatric cardiovascular disease and its potential to address the challenges of transparency in delivery of care to this unique population.
Proteasome-associated deubiquitinase ubiquitin-specific protease 14 regulates prostate cancer proliferation by deubiquitinating and stabilizing androgen receptor
Authors: Liao Yuning , Liu Ningning , Hua Xianliang , Cai Jianyu , Xia Xiaohong , Wang Xuejun , Huang Hongbiao , Liu Jinbao
Published: February 2017

Androgen receptor (AR) is frequently over-expressed and plays a critical role in the growth and progression of human prostate cancer. The therapy attempting to target AR signalling was established in decades ago but the treatment of prostate cancer is far from being satisfactory. The assignable cause is that our understanding of the mechanism of AR regulation and re-activation remains incomplete. Increasing evidence suggests that deubiquitinases are involved in the regulation of cancer development and progression but the specific underlying mechanism often is not elucidated. In the current study, we have identified ubiquitin-specific protease 14 (USP14) as a novel regulator of AR, inhibiting the degradation of AR via deubiquitinating this oncoprotein in the androgen-responsive prostate cancer cells. We found that (i) USP14 could bind to AR, and additionally, both genetic and pharmacological inhibition of USP14 accelerated the ubiquitination and degradation of AR; (ii) downregulation or inhibition of USP14 suppressed cell proliferation and colony formation of LNcap cells and, conversely, overexpression of USP14 promoted the proliferation; and (iii) reduction or inhibition of USP14 induced G0/G1 phase arrest in LNcap prostate cancer cells. Hence, we conclude that USP14 promotes prostate cancer progression likely through stabilization of AR, suggesting that USP14 could be a promising therapeutic target for prostate cancer.
RIPK1/RIPK3 promotes vascular permeability to allow tumor cell extravasation independent of its necroptotic function
Authors: Hänggi Kay , Vasilikos Lazaros , Valls Aida Freire , Yerbes Rosario , Knop Janin , Spilgies Lisanne M , Rieck Kristy , Misra Tvisha , Bertin John , Gough Peter J , Schmidt Thomas , de Almodòvar Carmen Ruiz , Wong W Wei-Lynn
Published: February 2017

Necroptosis is an inflammatory form of programmed cell death requiring receptor-interacting protein kinase 1, 3 (RIPK1, RIPK3) and mixed lineage kinase domain-like protein (MLKL). The kinase of RIPK3 phosphorylates MLKL causing MLKL to form a pore-like structure, allowing intracellular contents to release and cell death to occur. Alternatively, RIPK1 and RIPK3 have been shown to regulate cytokine production directly influencing inflammatory immune infiltrates. Recent data suggest that necroptosis may contribute to the malignant transformation of tumor cells in vivo and we asked whether necroptosis may have a role in the tumor microenvironment altering the ability of the tumor to grow or metastasize. To determine if necroptosis in the tumor microenvironment could promote inflammation alone or by initiating necroptosis and thereby influencing growth or metastasis of tumors, we utilized a syngeneic tumor model of metastasis. Loss of RIPK3 in the tumor microenvironment reduced the number of tumor nodules in the lung by 46%. Loss of the kinase activity in RIPK1, a member of the necrosome also reduced tumor nodules in the lung by 38%. However, the loss of kinase activity in RIPK3 or the loss of MLKL only marginally altered the ability of tumor cells to form in the lung. Using bone marrow chimeras, the decrease in tumor nodules in the Ripk3−/− appeared to be due to the stromal compartment rather than the hematopoietic compartment. Transmigration assays showed decreased ability of tumor cells to transmigrate through the vascular endothelial layer, which correlated with decreased permeability in the Ripk3−/− mice after tumor injection. In response to permeability factors, such as vascular endothelial growth factor, RIPK3 null endothelial cells showed decreased p38/HSP27 activation. Taken together, our results suggest an alternative function for RIPK1/RIPK3 in vascular permeability leading to decreased number of metastasis.
Using quantum theory to simplify input–output processes
Authors: Thompson Jayne , Garner Andrew J. P. , Vedral Vlatko , Gu Mile
Published: February 2017

All natural things process and transform information. They receive environmental information as input, and transform it into appropriate output responses. Much of science is dedicated to building models of such systems—algorithmic abstractions of their input–output behavior that allow us to simulate how such systems can behave in the future, conditioned on what has transpired in the past. Here, we show that classical models cannot avoid inefficiency—storing past information that is unnecessary for correct future simulation. We construct quantum models that mitigate this waste, whenever it is physically possible to do so. This suggests that the complexity of general input–output processes depends fundamentally on what sort of information theory we use to describe them.
The Fecal Microbial Community of Breast-fed Infants from Armenia and Georgia
Authors: Lewis Zachery T , Sidamonidze Ketevan , Tsaturyan Vardan , Tsereteli David , Khachidze Nika , Pepoyan Astghik , Zhgenti Ekaterine , Tevzadze Liana , Manvelyan Anahit , Balayan Marine , Imnadze Paata , Torok Tamas , Lemay Danielle G. , Mills David A.
Published: February 2017

Multiple factors help shape the infant intestinal microbiota early in life. Environmental conditions such as the presence of bioactive molecules from breast milk dictate gut microbial growth and survival. Infants also receive distinct, personalized, bacterial exposures leading to differential colonization. Microbial exposures and gut environmental conditions differ between infants in different locations, as does the typical microbial community structure in an infant’s gut. Here we evaluate potential influences on the infant gut microbiota through a longitudinal study on cohorts of breast-fed infants from the neighboring countries of Armenia and Georgia, an area of the world for which the infant microbiome has not been previously investigated. Marker gene sequencing of 16S ribosomal genes revealed that the gut microbial communities of infants from these countries were dominated by bifidobacteria, were different from each other, and were marginally influenced by their mother’s secretor status. Species-level differences in the bifidobacterial communities of each country and birth method were also observed. These community differences suggest that environmental variation between individuals in different locations may influence the gut microbiota of infants.
Significant survival benefit of adjuvant chemotherapy after concurrent chemoradiotherapy in locally advanced high-risk nasopharyngeal carcinoma
Authors: Liang Zhong-Guo , Chen Xiao-Qian , Lin Guo-Xiang , Yu Bin-Bin , Chen Kai-Hua , Zhong Qiu-Lu , Nong Si-Kai , Li Ling , Qu Song , Su Fang , Zhao Wei , Li Ye , Zhu Xiao-Dong
Published: February 2017

The present study aimed to define high-risk patients who may benefit from additional adjuvant chemotherapy (AC) after concurrent chemotherapy in combination with intensity-modulated radiotherapy among patients with loco-regionally advanced nasopharyngeal carcinoma (NPC). A cohort of 511 NPC patients who received concomitant chemoradiotherapy (CCRT) with or without AC between January 2007 and December 2012 were retrospectively analysed. One hundred seventy-seven patients received CCRT alone, whereas 334 received CCRT + AC. The survival analysis showed that ages >45 years old, T3-T4 stages, N2-N3 disease and serum albumin levels ≤42 g/L were significant independent prognostic factors for overall survival (OS). Using these four risk factors, a prognostic model for OS was created as follows: (1) low-risk group: 0–1 risk factors; and (2) high-risk group: 2–4 risk factors. In the CCRT alone and CCRT + AC groups, significant differences in survival were found between the high- and low-risk groups. Patients in the high-risk group exhibited improved OS due to the addition of AC to CCRT, but no survival benefits were found in the low-risk group. In conclusion, high-risk patients may benefit from the addition of AC to CCRT regarding OS.
Ultrahigh Charpy impact toughness (~450J) achieved in high strength ferrite/martensite laminated steels
Authors: Cao Wenquan , Zhang Mingda , Huang Chongxiang , Xiao Shuyang , Dong Han , Weng Yuqing
Published: February 2017

Strength and toughness are a couple of paradox as similar as strength-ductility trade-off in homogenous materials, body-centered-cubic steels in particular. Here we report a simple way to get ultrahigh toughness without sacrificing strength. By simple alloying design and hot rolling the 5Mn3Al steels in ferrite/austenite dual phase temperature region, we obtain a series of ferrite/martensite laminated steels that show up-to 400–450J Charpy V-notch impact energy combined with a tensile strength as high as 1.0–1.2 GPa at room temperature, which is nearly 3–5 times higher than that of conventional low alloy steels at similar strength level. This remarkably enhanced toughness is mainly attributed to the delamination between ferrite and martensite lamellae. The current finding gives us a promising way to produce high strength steel with ultrahigh impact toughness by simple alloying design and hot rolling in industry.
PhCESA3 silencing inhibits elongation and stimulates radial expansion in petunia
Authors: Yang Weiyuan , Cai Yuanping , Hu Li , Wei Qian , Chen Guoju , Bai Mei , Wu Hong , Liu Juanxu , Yu Yixun
Published: February 2017

Cellulose synthase catalytic subunits (CESAs) play important roles in plant growth, development and disease resistance. Previous studies have shown an essential role of Arabidopsis thaliana CESA3 in plant growth. However, little is known about the role of CESA3 in species other than A. thaliana. To gain a better understanding of CESA3, the petunia (Petunia hybrida) PhCESA3 gene was isolated, and the role of PhCESA3 in plant growth was analyzed in a wide range of plants. PhCESA3 mRNA was present at varying levels in tissues examined. VIGS-mediated PhCESA3 silencing resulted in dwarfing of plant height, which was consistent with the phenotype of the A. thaliana rsw1 mutant (a temperature-sensitive allele of AtCESA1), the A. thaliana cev1 mutant (the AtCESA3 mild mutant), and the antisense AtCESA3 line. However, PhCESA3 silencing led to swollen stems, pedicels, filaments, styles and epidermal hairs as well as thickened leaves and corollas, which were not observed in the A. thaliana cev1 mutant, the rsw1 mutant and the antisense AtCESA3 line. Further micrographs showed that PhCESA3 silencing reduced the length and increased the width of cells, suggesting that PhCESA3 silencing inhibits elongation and stimulates radial expansion in petunia.
Genome-wide DNA methylation reprogramming in response to inorganic arsenic links inhibition of CTCF binding, DNMT expression and cellular transformation
Authors: Rea Matthew , Eckstein Meredith , Eleazer Rebekah , Smith Caroline , Fondufe-Mittendorf Yvonne N.
Published: February 2017

Chronic low dose inorganic arsenic (iAs) exposure leads to changes in gene expression and epithelial-to-mesenchymal transformation. During this transformation, cells adopt a fibroblast-like phenotype accompanied by profound gene expression changes. While many mechanisms have been implicated in this transformation, studies that focus on the role of epigenetic alterations in this process are just emerging. DNA methylation controls gene expression in physiologic and pathologic states. Several studies show alterations in DNA methylation patterns in iAs-mediated pathogenesis, but these studies focused on single genes. We present a comprehensive genome-wide DNA methylation analysis using methyl-sequencing to measure changes between normal and iAs-transformed cells. Additionally, these differential methylation changes correlated positively with changes in gene expression and alternative splicing. Interestingly, most of these differentially methylated genes function in cell adhesion and communication pathways. To gain insight into how genomic DNA methylation patterns are regulated during iAs-mediated carcinogenesis, we show that iAs probably targets CTCF binding at the promoter of DNA methyltransferases, regulating their expression. These findings reveal how CTCF binding regulates DNA methyltransferase to reprogram the methylome in response to an environmental toxin.
High density lipoprotein (HDL) particles from end-stage renal disease patients are defective in promoting reverse cholesterol transport
Authors: Anderson Josephine L.C. , Gautier Thomas , Nijstad Niels , Tölle Markus , Schuchardt Mirjam , van der Giet Markus , Tietge Uwe J.F.
Published: February 2017

Atherosclerotic cardiovascular disease (CVD) represents the largest cause of mortality in end-stage renal disease (ESRD). CVD in ESRD is not explained by classical CVD risk factors such as HDL cholesterol mass levels making functional alterations of lipoproteins conceivable. HDL functions in atheroprotection by promoting reverse cholesterol transport (RCT), comprising cholesterol efflux from macrophage foam cells, uptake into hepatocytes and final excretion into the feces. ESRD-HDL (n = 15) were compared to healthy control HDL (n = 15) for their capacity to promote in vitro (i) cholesterol efflux from THP-1 macrophage foam cells and (ii) SR-BI-mediated selective uptake into ldla[SR-BI] cells as well as (iii) in vivo RCT. Compared with HDL from controls, ESRD-HDL displayed a significant reduction in mediating cholesterol efflux (p < 0.001) and SR-BI-mediated selective uptake (p < 0.01), two key steps in RCT. Consistently, also the in vivo capacity of ESRD-HDL to promote RCT when infused into wild-type mice was significantly impaired (p < 0.01). In vitro oxidation of HDL from healthy controls with hypochloric acid was able to fully mimic the impaired biological activities of ESRD-HDL. In conclusion, we demonstrate that HDL from ESRD patients is dysfunctional in key steps as well as overall RCT, likely due to oxidative modification.
Cellular prion protein is present in mitochondria of healthy mice
Authors: Faris Robert , Moore Roger A. , Ward Anne , Race Brent , Dorward David W. , Hollister Jason R. , Fischer Elizabeth R. , Priola Suzette A.
Published: February 2017

Cellular prion protein (PrPC) is a mammalian glycoprotein which is usually found anchored to the plasma membrane via a glycophosphatidylinositol (GPI) anchor. PrPC misfolds to a pathogenic isoform PrPSc, the causative agent of neurodegenerative prion diseases. The precise function of PrPC remains elusive but may depend upon its cellular localization. Here we show that PrPC is present in brain mitochondria from 6–12 week old wild-type and transgenic mice in the absence of disease. Mitochondrial PrPC was fully processed with mature N-linked glycans and did not require the GPI anchor for localization. Protease treatment of purified mitochondria suggested that mitochondrial PrPC exists as a transmembrane isoform with the C-terminus facing the mitochondrial matrix and the N-terminus facing the intermembrane space. Taken together, our data suggest that PrPC can be found in mitochondria in the absence of disease, old age, mutation, or overexpression and that PrPC may affect mitochondrial function.
Cell-free measurements of brightness of fluorescently labeled antibodies
Authors: Zhou Haiying , Tourkakis George , Shi Dennis , Kim David M. , Zhang Hairong , Du Tommy , Eades William C. , Berezin Mikhail Y.
Published: February 2017

Validation of imaging contrast agents, such as fluorescently labeled imaging antibodies, has been recognized as a critical challenge in clinical and preclinical studies. As the number of applications for imaging antibodies grows, these materials are increasingly being subjected to careful scrutiny. Antibody fluorescent brightness is one of the key parameters that is of critical importance. Direct measurements of the brightness with common spectroscopy methods are challenging, because the fluorescent properties of the imaging antibodies are highly sensitive to the methods of conjugation, degree of labeling, and contamination with free dyes. Traditional methods rely on cell-based assays that lack reproducibility and accuracy. In this manuscript, we present a novel and general approach for measuring the brightness using antibody-avid polystyrene beads and flow cytometry. As compared to a cell-based method, the described technique is rapid, quantitative, and highly reproducible. The proposed method requires less than ten microgram of sample and is applicable for optimizing synthetic conjugation procedures, testing commercial imaging antibodies, and performing high-throughput validation of conjugation procedures.
Piezoelectric scattering limited mobility of hybrid organic-inorganic perovskites CH3NH3PbI3
Authors: Lu Ying-Bo , Kong Xianghua , Chen Xiaobin , Cooke David G. , Guo Hong
Published: February 2017

Carrier mobility is one of the most important parameters for semiconducting materials and their use in optoelectronic devices. Here we report a systematic first principles analysis of the acoustic phonon scattering mechanism that limits the mobility of CH3NH3PbI3 (MAPbI3) perovskites. Due to the unique hybrid organic-inorganic structure, the mechanical, electronic and transport properties are dominated by the same factor, i.e. the weak interatomic bond and the easy rotation of methylammonium (MA) molecules under strain. Both factors make MAPbI3 soft. Rotation of MA molecule induces a transverse shift between Pb and I atoms, resulting in a very low deformation potential and a strong piezoelectricity in MAPbI3. Hence the carrier mobility of pristine MAPbI3 is limited by the piezoelectric scattering, which is consistent to the form of its temperature dependence. Our calculations suggest that in the pristine limit, a high mobility of about several thousand cm2 V−1 S−1 is expected for MAPbI3.
Size-dependent cellular uptake mechanism and cytotoxicity toward calcium oxalate on Vero cells
Authors: Sun Xin-Yuan , Gan Qiong-Zhi , Ouyang Jian-Ming
Published: February 2017

Urinary crystals with various sizes are present in healthy individuals and patients with kidney stone; however, the cellular uptake mechanism of calcium oxalate of various sizes has not been elucidated. This study aims to compare the internalization of nano-/micron-sized (50 nm, 100 nm, and 1 μm) calcium oxalate monohydrate (COM) and dihydrate (COD) crystals in African green monkey renal epithelial (Vero) cells. The internalization and adhesion of COM and COD crystals to Vero cells were enhanced with decreasing crystal size. Cell death rate was positively related to the amount of adhered and internalized crystals and exhibited higher correlation with internalization than that with adhesion. Vero cells mainly internalized nano-sized COM and COD crystals through clathrin-mediated pathways as well as micron-sized crystals through macropinocytosis. The internalized COM and COD crystals were distributed in the lysosomes and destroyed lysosomal integrity to some extent. The results of this study indicated that the size of crystal affected cellular uptake mechanism, and may provide an enlightenment for finding potential inhibitors of crystal uptake, thereby decreasing cell injury and the occurrence of kidney stones.
Probing the degradation and homogeneity of embedded perovskite semiconducting layers in photovoltaic devices by Raman spectroscopy
Authors: Hooper K. E. A. , Lee H. K. H. , Newman M. J. , Meroni S. , Baker J. , Watson T. M. , Tsoi W. C.
Published: February 2017

Raman spectroscopy is demonstrated to be unique in probing the degradation and homogeneity of embedded perovskite layers in devices and modules.
Solubility curves and nucleation rates from molecular dynamics for polymorph prediction – moving beyond lattice energy minimization
Authors: Parks Conor , Koswara Andy , DeVilbiss Frank , Tung Hsien-Hsin , Nere Nandkishor K. , Bordawekar Shailendra , Nagy Zoltan K. , Ramkrishna Doraiswami
Published: February 2017

Seeded nucleation simulations allow for the screening of low energy structures to predict final structure present in solution.
Lateral and flexural phonon thermal transport in graphene and stanene bilayers
Authors: Hong Yang , Zhu Chongqin , Ju Minggang , Zhang Jingchao , Zeng Xiao Cheng
Published: February 2017

The predicted in-plane thermal conductivity of the graphene/stanene hetero-bilayer is 311.1 W m−1 K−1, higher than most 2D materials such as phosphorene, hexagonal boron nitride, MoS2 and MoSe2.
Infrared spectroscopic study of absorption and separation of CO using copper(i)-containing ionic liquids
Authors: Repper Stephen E. , Haynes Anthony , Ditzel Evert J. , Sunley Glenn J.
Published: February 2017

Reversible formation of copper(i) carbonyl complexes from copper-containing ionic liquids is probed directly usingin situhigh pressure IR spectroscopy.
An efficient nickel oxides/nickel structure for water oxidation: a new strategy
Authors: Najafpour Mohammad Mahdi , Moghaddam Navid Jameei
Published: February 2017

A low-cost and very simple method to synthesize an efficient water-oxidizing nickel-based electrode was reported.
Sonogashira coupling in 3D-printed NMR cuvettes: synthesis and properties of arylnaphthylalkynes
Authors: Lederle Felix , Meyer Frederick , Kaldun Christian , Namyslo Jan C. , Hübner Eike G.
Published: February 2017

A set of push–pull substituted arylnaphthylalkynes has been synthesized under inert gas conditions in 3D-printed cuvettes out of NMR-transparent polyamide and their optical properties were investigated.
Positive feedback technique and split‐length transistors for DC‐gain enhancement of two‐stage op‐amps
Authors: Anisheh Seyed Mahmoud , Shamsi Hossein , Mirhassani Mitra
Published: February 2017

This study presents the design and simulation of a fully differential two‐stage op‐amp in a 0.18 μm complementary metal–oxide–semiconductor process with a 1.8 V supply voltage. In this op‐amp, positive feedback technique and split‐length transistors (SLTs) are employed to increase the DC‐gain of the op‐amp by about 22 dB without affecting the unity‐gain bandwidth (UGBW), stability, power dissipation and output voltage swing of the conventional two‐stage op‐amp. A comprehensive analysis is provided for differential‐mode gain, common‐mode gain, power supply rejection ratio, input‐referred noise, input offset, frequency response and the effect of using SLTs on DC‐gain sensitivity. The proposed op‐amp is utilised in a flip‐around sample‐and‐hold amplifier (SHA). The output spectrum of the SHA shows the total harmonic distortion of 0.0023%. The post‐layout and Monte Carlo simulation results show that the proposed op‐amp has better performance than the state‐of‐the‐art designs.
In Vitro and In Vivo Study of the Gastrointestinal Absorption and Metabolisation of Hymenocardine, a Cyclopeptide Alkaloid
Authors: Tuenter Emmy , Bijttebier Sebastiaan , Foubert Kenn , Breynaert Annelies , Apers Sandra , Hermans Nina , Pieters Luc
Published: February 2017

Hymenocardine is a cyclopeptide alkaloid present in the root bark of Hymenocardia acida. In traditional African medicine, the leaves and roots of this plant are used to treat malaria, and moderate in vitro antiplasmodial activity has been reported for hymenocardine. However, in view of its peptide-like nature, potential metabolisation after oral ingestion has to be taken into account when considering in vivo experiments. In this study, the stability and small intestinal absorption of hymenocardine was assessed using an in vitro gastrointestinal dialysis model. In addition, potential liver metabolisation was investigated in vitro by incubation with a human S9 fraction. Moreover, hymenocardine was administered to rats per os, and blood and urine samples were collected until 48 and 24 h after oral administration, respectively. All samples resulting from these three experiments were analyzed by LC-MS. Analysis of the dialysate and retentate, obtained from the gastrointestinal dialysis model, indicated that hymenocardine is absorbed unchanged from the gastrointestinal tract, at least in part. After S9 metabolisation, several metabolites of hymenocardine could be identified, the major ones being formed by the reduction and/or the loss of an N-methyl group. The in vivo study confirmed that hymenocardine is absorbed from the gastrointestinal tract unchanged, since it could be identified in both rat plasma and urine, together with hymenocardinol, its reduction product.
Reduced-mobility layers with high internal mobility in poly(ethylene oxide)–silica nanocomposites
Authors: Golitsyn Yury , Schneider Gerald J. , Saalwächter Kay
Published: February 2017

A series of poly(ethylene oxide) nanocomposites with spherical silica was studied by proton NMR spectroscopy, identifying and characterizing reduced-mobility components arising from either room-temperature lateral adsorption or possibly end-group mediated high-temperature bonding to the silica surface. The study complements earlier neutron-scattering results for some of the samples. The estimated thickness of a layer characterized by significant internal mobility resembling backbone rotation ranges from 2 nm for longer (20 k) chains adsorbed on 42 nm diameter particles to 0.5 nm and below for shorter (2 k) chains on 13 nm particles. In the latter case, even lower adsorbed amounts are found when hydroxy endgroups are replaced by methyl endgroups. Both heating and water addition do not lead to significant changes of the observables, in contrast to other systems such as acrylate polymers adsorbed to silica, where temperature- and solvent-induced softening associated with a glass transition temperature gradient was evidenced. We highlight the actual agreement and complementarity of NMR and neutron scattering results, with the earlier ambiguities mainly arising from different sensitivities to the component fractions and the details of their mobility.
Interfacial interaction and glassy dynamics in stacked thin films of poly(methyl methacrylate)
Authors: Hayashi Tatsuhiko , Segawa Kenta , Sadakane Koichiro , Fukao Koji , Yamada Norifumi L.
Published: February 2017

Neutron reflectivity and dielectric permittivity of alternately stacked thin films of protonated and deuterated poly(methyl methacrylate) were measured to elucidate a correlation between the time evolution of the interfacial structure and the segmental dynamics in the stacked thin polymer films during isothermal annealing above the glass transition temperature. The roughness at the interface between two thin layers increases with the annealing time, whereas the relaxation rate and strength of the α-process decrease with an increase in the annealing time. A strong correlation between the time evolution of the interfacial structure and the dynamics of the α-process during annealing could be observed using neutron reflectivity and dielectric relaxation measurements.
Unfolding DNA condensates produced by DNA-like charged depletants: A force spectroscopy study
Authors: Lima C. H. M. , Rocha M. S. , Ramos E. B.
Published: February 2017

In this work, we have measured, by means of optical tweezers, forces acting on depletion-induced DNA condensates due to the presence of the DNA-like charged protein bovine serum albumin (BSA). The stretching and unfolding measurements performed on the semi-flexible DNA chain reveal (1) the softening of the uncondensed DNA contour length and (2) a mechanical behavior strikingly different from those previously observed: the force-extension curves of BSA-induced DNA condensates lack the “saw-tooth” pattern and applied external forces as high as ≈80 pN are unable to fully unfold the condensed DNA contour length. This last mechanical experimental finding is in agreement with force-induced “unpacking” detailed Langevin dynamics simulations recently performed by Cortini et al. on model rod-like shaped condensates. Furthermore, a simple thermodynamics analysis of the unfolding process has enabled us to estimate the free energy involved in the DNA condensation: the estimated depletion-induced interactions vary linearly with both the condensed DNA contour length and the BSA concentration, in agreement with the analytical and numerical analysis performed on model DNA condensates. We hope that future additional experiments can decide whether the rod-like morphology is the actual one we are dealing with (e.g. pulling experiments coupled with super-resolution fluorescence microscopy).
Structural and electrical properties of large area epitaxial VO2 films grown by electron beam evaporation
Authors: Théry V. , Boulle A. , Crunteanu A. , Orlianges J. C. , Beaumont A. , Mayet R. , Mennai A. , Cosset F. , Bessaudou A. , Fabert M.
Published: February 2017

Large area (up to 4 squared inches) epitaxial VO2 films, with a uniform thickness and exhibiting an abrupt metal-insulator transition with a resistivity ratio as high as 2.85×104, have been grown on (001)-oriented sapphire substrates by electron beam evaporation. The lattice distortions (mosaicity) and the level of strain in the films have been assessed by X-ray diffraction. It is demonstrated that the films grow in a domain-matching mode where the distortions are confined close to the interface which allows growth of high-quality materials despite the high film-substrate lattice mismatch. It is further shown that a post-deposition high-temperature oxygen annealing step is crucial to ensure the correct film stoichiometry and provide the best structural and electrical properties. Alternatively, it is possible to obtain high quality films with a RF discharge during deposition, which hence do not require the additional annealing step. Such films exhibit similar electrical properties and only slightly degraded structural properties.
Self-organized patterns of fullerene on molecular nanotemplate
Authors: Jin Jing , Song Xin , Wang Zhongping , Liu Xiaoqing , Wang Li
Published: February 2017

Row structures and close packed islands of fullerenes controlled by a stable molecular nanotemplate formed via rubrene on Au(111) have been investigated by scanning tunneling microscopy. The fullerene rows are made up of short chains linked by two to four molecules at low fullerene coverage, while they consisted of dimers or trimers with the increase of the coverage and the assistance of further annealing. The close-packed islands of fullerene are described as a hexagonal cubic structure. The growth of the islands can overcome the hindrance of the terrace edges and expand from one terrace to the other without breaking their periodic structures.
Pure spin current transport in gallium doped zinc oxide
Authors: Althammer Matthias , Mukherjee Joynarayan , Geprägs Stephan , Goennenwein Sebastian T. B. , Opel Matthias , Ramachandra Rao M. S. , Gross Rudolf
Published: February 2017

We study the flow of a pure spin current through zinc oxide by measuring the spin Hall magnetoresistance (SMR) in thin film trilayer samples consisting of bismuth-substituted yttrium iron garnet (Bi:YIG), gallium-doped zinc oxide (Ga:ZnO), and platinum. We investigate the dependence of the SMR magnitude on the thickness of the Ga:ZnO interlayer and compare to a Bi:YIG/Pt bilayer. We find that the SMR magnitude is reduced by almost one order of magnitude upon inserting a Ga:ZnO interlayer and continuously decreases with increasing interlayer thickness. Nevertheless, the SMR stays finite even for a 12 nm thick Ga:ZnO interlayer. These results show that a pure spin current indeed can propagate through a several nm-thick degenerately doped zinc oxide layer. We also observe differences in both the temperature and the field dependence of the SMR when comparing tri- and bilayers. Finally, we compare our data to the predictions of a model based on spin diffusion. This shows that interface resistances play a crucial role for the SMR magnitude in these trilayer structures.
Harnessing host ROS-generating machinery for the robust genome replication of a plant RNA virus
Authors: Hyodo Kiwamu , Hashimoto Kenji , Kuchitsu Kazuyuki , Suzuki Nobuhiro , Okuno Tetsuro
Published: February 2017

Significance

Reactive oxygen species (ROS) production is induced by multiple environmental stresses in various organisms. In plants, ROS transduce local and systemic signaling for adaptation and tolerance to these stresses. Here we show that red clover necrotic mosaic virus (RCNMV), a plant positive-strand RNA [(+)RNA] virus, hijacks the host’s ROS-generating machinery during infection. An RCNMV replication protein associates with host ROS-generating machinery and triggers intracellular ROS bursts. These bursts are required for robust viral RNA replication. We further show that another (+)RNA virus, brome mosaic virus, also depends on ROS for replication. This study represents an example of diversion of a plant stress-resilience system for robust virus replication.
The nonreceptor tyrosine kinase c-Src attenuates SCF(β-TrCP) E3-ligase activity abrogating Taz proteasomal degradation
Authors: Shanzer Matan , Adler Julia , Ricardo-Lax Inna , Reuven Nina , Shaul Yosef
Published: February 2017

Significance

Taz (transcriptional coactivator with PDZ-binding motif) and Yap (yes-associated protein), the Hippo pathway effector proteins regulating cell fate, organ size, and homeostasis, are targeted by the potent viral oncogene polyomavirus middle T antigen (PyMT). A key process of PyMT is the activation of Src, a cellular proto-oncogene. Remarkably, active Src prevents the Hippo pathway from enhancing Taz decay mediated by its E3-ubiquitin ligase SCF(β-TrCP). We resolved the underlying mechanism by demonstrating that Src inhibits β-TrCP. β-TrCP is a key cellular component regulating a wide range of cellular signaling in cell fate determination. Our discovery of a function of the well-studied Src tyrosine kinase in abrogating β-TrCP function is expected to have wide ramifications for cell fate determination, including in oncogenesis.
Influence of shot peening on the mechanical properties of bulk amorphous Vitreloy 105
Authors: Grell Daniel , Gibmeier Jens , Dietrich Stefan , Silze Frank , Böhme Luisa , Schulze Volker , Kühn Uta , Kerscher Eberhard
Published: February 2017

The quasi-static and cyclic properties of bulk glassy Zr52.5Cu17.9Al10Ni14.6Ti5 alloy (Vitreloy 105) were investigated under three-point bending conditions for two different shot-peened surface states. Residual stress analysis and nanoindentation measurements revealed the presence of compressive residual stresses and an enhanced hardness in the near surface layer after shot peening. Further investigations of the longitudinal cross-sections of the mechanically tested specimens by optical and scanning electron microscopy showed small cracks propagating along shear bands in the vicinity of the fracture surface. The results are in accordance with the improved plasticity of the shot-peened states under quasi-static loading conditions compared to the as-cast reference state. All mechanical testing was carried out with the aim to find a material's state with improved mechanical properties with a special focus on the improvement of the fatigue lifetime and the endurance limit of Vitreloy 105 bulk metallic glass.
The dynamics of a recovering fish stock: Georges Bank herring
Authors: Melvin Gary D. , Stephenson Robert L.
Published: February 2017

Melvin, G. D., and Stephenson, R. L. 2007. The dynamics of a recovering fish stock: Georges Bank herring – ICES Journal of Marine Science, 64, 69–82. The decline and subsequent recovery of Georges Bank Atlantic herring (Clupea harengus) provides a rare opportunity to examine the dynamics of a recovering fish population. Moreover, the near absence of a commercial fishery on Georges Bank between 1978 and 1995 removes the confounding effects of exploitation during the recovery period. Herring abundance on Georges Bank increased and the distribution of adult spawning fish evolved from a few isolated locations to most of the northern fringe during the period 1983–1995. The distribution of recently hatched larvae also expanded in a manner consistent with progressive occupation of historical spawning grounds. Changes in the size composition and age structure of herring during the spawning season broadened from the dominance of a single age class to multiple year classes as the stock recovered and expanded. Growth, as reflected by length-at-age, decreased significantly and was correlated with the number of fish estimated to be in the stock. This and the observed difference in mean length and length at first spawning during the recovery provide strong evidence of density-dependent growth. In particular, there is a highly correlated (p<0.01) relationship between the number of 4+ herring in the stock at the start of the year and the mean length of herring aged 3 recruiting to the spawning stock in autumn of the same year. A mechanism based on an extended period of prespawning interaction is proposed to explain the density-dependence.