bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Reynolds number and Stokes number on particle-pair relative velocity in isotropic turbulence: a systematic experimental study
Authors: Dou Zhongwang , Bragg Andrew D. , Hammond Adam L. , Liang Zach , Collins Lance R. , Meng Hui
Published: January 2018

The effects of Reynolds number ($R_{\unicode[STIX]{x1D706}}$) and Stokes number ($St$) on particle-pair relative velocity (RV) are investigated systematically using a recently developed planar four-frame particle tracking technique in a novel homogeneous and isotropic turbulence chamber. We compare the measured results with direct numerical simulation (DNS), verifying whether the conclusions of the DNS for simplified conditions and limited $R_{\unicode[STIX]{x1D706}}$ are still valid in reality. Two experiments are performed: varying $R_{\unicode[STIX]{x1D706}}$ between 246 and 357 at six $St$ values, and varying $St$ between 0.02 and 4.63 at five $R_{\unicode[STIX]{x1D706}}$ values. The measured mean inward particle-pair RV $\langle w_{r}^{-}\rangle$ as a function of separation distance $r$ is compared with the DNS under closely matched conditions. At all experimental conditions, an excellent agreement is achieved, except when the particle separation distance $r\lesssim 10\unicode[STIX]{x1D702}$ ($\unicode[STIX]{x1D702}$ is the Kolmogorov length scale), where the experimental $\langle w_{r}^{-}\rangle$ is consistently higher, possibly due to particle polydispersity and finite laser thickness in the experiments (Dou et al., arXiv:1712.07506, 2017). At any fixed $St,\langle w_{r}^{-}\rangle$ is essentially independent of $R_{\unicode[STIX]{x1D706}}$, echoing the DNS finding of Ireland et al. (J. Fluid Mech., vol. 796, 2016, pp. 617–658). At any fixed $R_{\unicode[STIX]{x1D706}}$, $\langle w_{r}^{-}\rangle$ increases with $St$ at small $r$, showing dominance of the path-history effect in the dissipation range when $St\gtrsim O(1)$, but decreases with $St$ at large $r$, indicating dominance of inertial filtering. We further compare the $\langle w_{r}^{-}\rangle$ and RV variance $\langle w_{r}^{2}\rangle$ from experiments with DNS and theoretical predictions by Pan & Padoan (J. Fluid Mech., vol. 661, 2010, pp. 73–107). For $St\lesssim 1$, experimental $\langle w_{r}^{-}\rangle$ and $\langle w_{r}^{2}\rangle$ match these values well at $r\gtrsim 10\unicode[STIX]{x1D702}$, but they are higher than both DNS and theory at $r\lesssim 10\unicode[STIX]{x1D702}$. For $St\gtrsim 1$, $\langle w_{r}^{-}\rangle$ from all three match well, except for $r\lesssim 10\unicode[STIX]{x1D702}$, for which experimental values are higher, while $\langle w_{r}^{2}\rangle$ from experiment and DNS are much higher than theoretical predictions. We discuss potential causes of these discrepancies. What this study shows is the first experimental validation of $R_{\unicode[STIX]{x1D706}}$ and $St$ effect on inertial particle-pair $\langle w_{r}^{-}\rangle$ in homogeneous and isotropic turbulence.
Two-level, two-phase model for intense, turbulent sediment transport
Authors: Gonzalez-Ondina Jose M. , Fraccarollo Luigi , Liu Philip L.-F.
Published: January 2018

The study of sediment transport requires in-depth investigation of the complex effects of sediment particles in fluid turbulence. In this paper we focus on intense sediment transport flows. None of the existing two-phase models in the literature properly replicates the liquid and solid stresses in the near bed region of high concentration of sediment. The reason for this shortcoming is that the physical processes occurring at the length scale of the particle collisions are different from those occurring at larger length scales and therefore, they must be modelled independently. We present here a two-level theoretical derivation of two-phase, Favre averaged Navier–Stokes equations (FANS). This approach treats two levels of energy fluctuations independently, those associated with a granular spatial scale (granular temperature and small-scale fluid turbulence) and those associated with the ensemble average (turbulent kinetic energy for the two phases). Although similar attempts have been made by other researchers, the two level approach ensures that the two relevant length scales are included independently in a more consistent manner. The model is endowed with a semi-empirical formulation for the granular scale fluid turbulence, which is important even in the dense collisional shear layer, as has been recently recognized. As a result of the large and small scale modelling of the liquid and solid fluctuations, predictions are promising to be reliable in a wide range of flow conditions, from collisional to turbulent suspensions. This model has been validated for steady state flows with intense, collisional or mixed collisional–turbulent sediment transport, using various sources of detailed experimental data. It compares well with the experimental results in the whole experimental range of Shields parameters, better than previous models, although at the cost of increased complexity in the equations. Further experiments on turbulent suspensions would be necessary to definitely assess the model capabilities.
Parametric instability, inverse cascade and the range of solar-wind turbulence
Authors: Chandran Benjamin D. G.
Published: January 2018

In this paper, weak-turbulence theory is used to investigate the nonlinear evolution of the parametric instability in three-dimensional low-$\unicode[STIX]{x1D6FD}$ plasmas at wavelengths much greater than the ion inertial length under the assumption that slow magnetosonic waves are strongly damped. It is shown analytically that the parametric instability leads to an inverse cascade of Alfvén wave quanta, and several exact solutions to the wave kinetic equations are presented. The main results of the paper concern the parametric decay of Alfvén waves that initially satisfy $e^{+}\gg e^{-}$, where $e^{+}$ and $e^{-}$ are the frequency ($f$) spectra of Alfvén waves propagating in opposite directions along the magnetic field lines. If $e^{+}$ initially has a peak frequency $f_{0}$ (at which $fe^{+}$ is maximized) and an ‘infrared’ scaling $f^{p}$ at smaller $f$ with $-1<p<1$, then $e^{+}$ acquires an $f^{-1}$ scaling throughout a range of frequencies that spreads out in both directions from $f_{0}$. At the same time, $e^{-}$ acquires an $f^{-2}$ scaling within this same frequency range. If the plasma parameters and infrared $e^{+}$ spectrum are chosen to match conditions in the fast solar wind at a heliocentric distance of 0.3 astronomical units (AU), then the nonlinear evolution of the parametric instability leads to an $e^{+}$ spectrum that matches fast-wind measurements from the Helios spacecraft at 0.3 AU, including the observed $f^{-1}$ scaling at $f\gtrsim 3\times 10^{-4}~\text{Hz}$. The results of this paper suggest that the $f^{-1}$ spectrum seen by Helios in the fast solar wind at $f\gtrsim 3\times 10^{-4}~\text{Hz}$ is produced in situ by parametric decay and that the $f^{-1}$ range of $e^{+}$ extends over an increasingly narrow range of frequencies as $r$ decreases below 0.3 AU. This prediction will be tested by measurements from the Parker Solar Probe.
Azimuthal magnetorotational instability with super-rotation
Authors: Rüdiger G. , Schultz M. , Gellert M. , Stefani F.
Published: January 2018

It is demonstrated that the azimuthal magnetorotational instability (AMRI) also works with radially increasing rotation rates contrary to the standard magnetorotational instability for axial fields which requires negative shear. The stability against non-axisymmetric perturbations of a conducting Taylor–Couette flow with positive shear under the influence of a toroidal magnetic field is considered if the background field between the cylinders is current free. For small magnetic Prandtl number $Pm\rightarrow 0$ the curves of neutral stability converge in the (Hartmann number,Reynolds number) plane approximating the stability curve obtained in the inductionless limit $Pm=0$. The numerical solutions for $Pm=0$ indicate the existence of a lower limit of the shear rate. For large $Pm$ the curves scale with the magnetic Reynolds number of the outer cylinder but the flow is always stable for magnetic Prandtl number unity as is typical for double-diffusive instabilities. We are particularly interested to know the minimum Hartmann number for neutral stability. For models with resting or almost resting inner cylinder and with perfectly conducting cylinder material the minimum Hartmann number occurs for a radius ratio of $r_{\text{in}}=0.9$. The corresponding critical Reynolds numbers are smaller than $10^{4}$.
Thamnolia tundrae sp. nov., a cryptic species and putative glacial relict
Authors: ONUT-BRÄNNSTRÖM Ioana , JOHANNESSON Hanna , TIBELL Leif
Published: January 2018

The lichen species of the genus Thamnolia, with their striking wormlike thalli and frequent occurrence in arctic and tundra environments, have often been debated with regard to the use of chemistry in lichen taxonomy. Phylogenetic studies have arrived at different conclusions as to the recognition of species in the genus, but in a recent study based on the analyses of six nuclear markers (genes or noncoding regions) of a worldwide sample of Thamnolia, we showed the existence of three well-supported lineages with two different chemistries and geographical distributions. Here, we present two analyses based on ITS and three markers, respectively, which were extended from the study mentioned above to include type specimens and additional Thamnolia strains and taxa. In these analyses the same three clades were retrieved. A putative DEAD-box helicase is used here for the first time as an informative phylogenetic marker to provide taxonomic resolution at species level. The distribution of morphological and chemical characters across the phylogeny was analyzed and it was concluded that three morphologically cryptic, but genetically well supported, species occur: T. vermicularis s. str., T. subuliformis s. str. and T. tundrae sp. nov. Thamnolia vermicularis s. str. contains individuals with uniform secondary chemistry (producing thamnolic acid) and a rather limited distribution in the European Alps, Tatra Mts and the Western Carpathians, a distribution which might result from glacial survival in an adjacent refugium/refugia. Thamnolia subuliformis s. str. is widely distributed in all hemispheres and the samples contain two chemotypes (either with thamnolic or squamatic acids). Thamnolia tundrae is described as new; it produces baeomycesic and squamatic acids, and has a distribution limited to the arctic tundra of Eurasia extending to the Aleutian Islands in North America. It may have survived the latest glaciation in coastal refugia near its present distribution. Thus, secondary chemistry alone is not suitable for characterizing species in Thamnolia, secondary chemistry and geographical origin are informative, and the ITS region can be confidently used for species recognition. Nomenclatural notes are given on several other names that have been used in Thamnolia.
Bacidina mendax sp. nov., a new widespread species in Central Europe, together with a new combination within the genus Bacidina
Authors: CZARNOTA Paweł , GUZOW-KRZEMIŃSKA Beata
Published: January 2018

Bacidina mendax, described here as a new lichen species, appears to be common and widespread, at least in Central Europe. Analyses of the ITS rDNA region and the morphology of specimens showed an intraspecific variation in the new taxon. It differs from B. neosquamulosa in the lack of a subsquamulose thallus, and from B. caligans in its longer and only slightly curved to apically hooked conidia and lack of a granular (sorediate) thallus. Since ITS rDNA data support the inclusion of Bacidia pycnidiata Czarnota & Coppins in the genus Bacidina, a new combination is proposed.
Low-light recovery effects on assessment of photoinhibition with chlorophyll fluorescence in lichens
Authors: SOLHAUG Knut Asbjørn
Published: January 2018

Chlorophyllafluorescence is often used to estimate various types of damage in lichens. In order to optimize the output and improve interpretations of such measurements the protocol for pretreatment and measuring is important. To study the effects of measurement conditions, the lichensLobaria pulmonaria,L. scrobiculata,Xanthoria parietinaandParmelia sulcatawere first stressed by high light intensities at 600 or 1000 µmol photons m−2s−1for 4 h. Then various conditions during recovery or pretreatment were used to optimize the detection of more lasting damage. Recovery from photoinhibition was incomplete in darkness, whereas light as low as 0·2 or 1·0 µmol m−2s−1resulted in complete recovery if the recovery period was long enough. Additionally, low intensity light given for1·5 h after one day in darkness caused rapid and complete recovery. In conclusion, before measuring maximal PSII efficiency (Fv/Fm) with chlorophyll fluorescence, it is important to let lichens recover in low intensity light and not in darkness, to optimize recovery from photoinhibition; dark adaptation can only be recommended if the photoinhibition status of the lichens is of interest.
Myriospora, a genus newly reported for Antarctica with a worldwide key to the species
Authors: PURVIS O. W. , FERNÁNDEZ-BRIME S. , WESTBERG M. , WEDIN M.
Published: January 2018

Myriospora signyensis Purvis, Fdez-Brime, M. Westb. & Wedin is described from Signy Island, South Orkney Islands, Antarctica, where it occurs predominantly on quartz mica schist. This represents the first record of the genus for Antarctica. The distinctive interrupted photobiont arrangement places it within the genus Myriospora (formerly known as the ‘Acarospora’ smaragdula group, or Silobia). The new species is characterized by having large, distinctly elevated, sessile apothecia with a prominent margin and a thallus that is usually lobed at the margins and variously orange-red, rust-coloured or brown-pigmented. Molecular phylogenetic analyses inferred with strong support that M. signyensis is closely related to M. scabrida which is similar in having a lobed, imbricate thallus with large and frequently somewhat raised apothecia, but which differs in never being rusty red, by frequently having a larger number of apothecia per areole/squamule and by having a thick and distinctive thalline epinecral layer. Myriospora signyensis is otherwise most similar to M. dilatata but the thallus of M. dilatata is never imbricate-lobate and the ascomata of M. signyensis have larger and more distinctly raised and sessile apothecia. A worldwide key to the 10 species currently recognized in the genus is presented.
A multi-tool approach to assess microalgal diversity in lichens: isolation, Sanger sequencing, HTS and ultrastructural correlations
Authors: MOLINS Arántzazu , MOYA Patricia , GARCÍA-BREIJO Francisco J. , REIG-ARMIÑANA José , BARRENO Eva
Published: January 2018

Lichen thalli represent the most conspicuous examples of fungal-algal interactions. Studies that describe phycobiont diversity within entire thalli are based mainly on Sanger sequencing. In some lichen species, this technique could underestimate the intrathalline coexistence of multiple microalgae. In this study different multi-tool approaches were applied to two lichen taxa,Circinaria hispidaandFlavoparmelia soredians, to detect algal coexistence. Here, we combined Sanger sequencing, a specific polymerase chain reaction (PCR) primer, 454-pyrosequencing, phycobiont isolation and ultrastructural characterization. Furthermore, we compared pyrenoid ultrastructural features of lichenized phycobionts with microalgae isolated in culture. An improved methodology was used to isolate and propagate phycobionts which, in combination with fast genetic identification, resulted in a considerable reduction in time and cost to complete the process. This isolation method, coupled with a specific PCR primer, allowed for the detection of coexisting algae inC. hispida(fourTrebouxialineages). 454-pyrosequencing detected only a fraction of such diversity, while Sanger sequencing identified only the primary phycobiont. Ultrastructural features of the isolated algae were observed by transmission electron microscopy; the maintenance of the pyrenoid characteristics suggested the existence of differentTrebouxialineages. InF. sorediansa singleTrebouxialineage was identified using all these approaches.

In cases of lichens with algal coexistence, a combination of different molecular and ultrastructural approaches may be required to reveal the underlying algal diversity within a single thallus. The approach proposed in this study provides information about the relationship between molecular and ultrastructural data, and represents an improvement in the delimitation of taxonomic features which is needed to recognize intrathallineTrebouxiadiversity.
Differential epitope masking reveals synapse-specific complexes of TRPM1
Authors: AGOSTO MELINA A. , ANASTASSOV IVAN A. , WENSEL THEODORE G.
Published: January 2018

The transient receptor potential channel TRPM1 is required for synaptic transmission between photoreceptors and the ON subtype of bipolar cells (ON-BPC), mediating depolarization in response to light. TRPM1 is present in the somas and postsynaptic dendritic tips of ON-BPCs. Monoclonal antibodies generated against full-length TRPM1 were found to have differential labeling patterns when used to immunostain the mouse retina, with some yielding reduced labeling of dendritic tips relative to the labeling of cell bodies. Epitope mapping revealed that those antibodies that poorly label the dendritic tips share a binding site (N2d) in the N-terminal arm near the transmembrane domain. A major splice variant of TRPM1 lacking exon 19 does not contain the N2d binding site, but quantitative immunoblotting revealed no enrichment of this variant in synaptsomes. One explanation of the differential labeling is masking of the N2d epitope by formation of a synapse-specific multiprotein complex. Identifying the binding partners that are specific for the fraction of TRPM1 present at the synapses is an ongoing challenge for understanding TRPM1 function.
Does the distribution frequency matter? A subgroup specific analysis of the effectiveness of the EU School Fruit and Vegetable Scheme in Germany comparing twice and thrice weekly deliveries
Authors: Haß Julia , Lischetzke Tanja , Hartmann Monika
Published: January 2018

Objective

The present study aimed to examine the effectiveness of two different implementation forms of the EU School Fruit and Vegetable Scheme (SFVS).

Design

A quasi-experimental design was applied including a thrice as well as a twice weekly intervention group. Repeated 24 h dietary recalls were used to measure children’s fruit and vegetable (F&V) intake. Effects were analysed on days with and without F&V deliveries using hierarchical linear regression models.

Setting

Twelve primary schools in North Rhine-Westphalia, Germany.

Subjects

Third and fourth graders (n664).

Results

Average daily F&V intake at pre-intervention was 0·84 frequencies in the thrice weekly intervention group, 0·90 frequencies in the twice weekly intervention group and 1·25 frequencies in the control group. Providing children thrice weekly with F&V increased children’s F&V intake on average by 0·96 (P<0·001) frequencies/d. The effects were higher on days with (1·07;P<0·001) than on days without (0·75;P<0·001) F&V deliveries. Distributing F&V twice weekly resulted in an increase of 0·75 (P<0·001) frequencies/d on average, again with higher effects on days with (1·30;P<0·001) than without (0·48;P<0·003) F&V deliveries. Subgroup analysis revealed some indications for differential effectiveness only in the twice weekly intervention group.

Conclusions

The SFVS with thrice or twice weekly deliveries of F&V led to a significant increase in children’s F&V intake on days with and without deliveries. The latter might provide an indication of positive long-term effects of the scheme. The scheme shows equal efficiency for almost all subgroups.
Octave-spanning coherent supercontinuum generation in silicon on insulator from 1.06 μm to beyond 2.4 μm
Authors: Singh Neetesh , Xin Ming , Vermeulen Diedrik , Shtyrkova Katia , Li Nanxi , Callahan Patrick T , Magden Emir Salih , Ruocco Alfonso , Fahrenkopf Nicholas , Baiocco Christopher , Kuo Bill P-P , Radic Stojan , Ippen Erich , Kärtner Franz X , Watts Michael R
Published: January 2018

Efficient complementary metal-oxide semiconductor-based nonlinear optical devices in the near-infrared are in strong demand. Due to two-photon absorption in silicon, however, much nonlinear research is shifting towards unconventional photonics platforms. In this work, we demonstrate the generation of an octave-spanning coherent supercontinuum in a silicon waveguide covering the spectral region from the near- to shortwave-infrared. With input pulses of 18 pJ in energy, the generated signal spans the wavelength range from the edge of the silicon transmission window, approximately 1.06 to beyond 2.4 μm, with a −20 dB bandwidth covering 1.124–2.4 μm. An octave-spanning supercontinuum was also observed at the energy levels as low as 4 pJ (−35 dB bandwidth). We also measured the coherence over an octave, obtaining "Equation missing", in good agreement with the simulations. In addition, we demonstrate optimization of the third-order dispersion of the waveguide to strengthen the dispersive wave and discuss the advantage of having a soliton at the long wavelength edge of an octave-spanning signal for nonlinear applications. This research paves the way for applications, such as chip-scale precision spectroscopy, optical coherence tomography, optical frequency metrology, frequency synthesis and wide-band wavelength division multiplexing in the telecom window.
Thermally stimulated exciton emission in Si nanocrystals
Authors: de Jong Elinore MLD , Rutjes Huub , Valenta Jan , Trinh M Tuan , Poddubny Alexander N , Yassievich Irina N , Capretti Antonio , Gregorkiewicz Tom
Published: January 2018

Increasing temperature is known to quench the excitonic emission of bulk silicon, which is due to thermally induced dissociation of excitons. Here, we demonstrate that the effect of temperature on the excitonic emission is reversed for quantum-confined silicon nanocrystals. Using laser-induced heating of silicon nanocrystals embedded in SiO2, we achieved a more than threefold (>300%) increase in the radiative (photon) emission rate. We theoretically modeled the observed enhancement in terms of the thermally stimulated effect, taking into account the massive phonon production under intense illumination. These results elucidate one more important advantage of silicon nanostructures, illustrating that their optical properties can be influenced by temperature. They also provide an important insight into the mechanisms of energy conversion and dissipation in ensembles of silicon nanocrystals in solid matrices. In practice, the radiative rate enhancement under strong continuous wave optical pumping is relevant for the possible application of silicon nanocrystals for spectral conversion layers in concentrator photovoltaics.
N6-methyladenosine links RNA metabolism to cancer progression
Authors: Dai Dongjun , Wang Hanying , Zhu Liyuan , Jin Hongchuan , Wang Xian
Published: January 2018

N6-methyladenosine (m6A) is the most abundant mRNA modification. With the development of antibody-based sequencing technologies and the findings of m6A-related “writers”, “erasers”, and “readers”, the relationships between m6A and mRNA metabolism are emerging. The m6A modification influences almost every step of RNA metabolism that comprises mRNA processing, mRNA exporting from nucleus to cytoplasm, mRNA translation, mRNA decay, and the biogenesis of long-non-coding RNA (lncRNA) and microRNA (miRNA). Recently, more and more studies have found m6A is associated with cancer, contributing to the self-renewal of cancer stem cell, promotion of cancer cell proliferation, and resistance to radiotherapy or chemotherapy. Inhibitors of m6A-related factors have been explored, and some of them were identified to inhibit cancer progression, indicating that m6A could be a target for cancer therapy. In this review, we are trying to summarize the regulation and function of m6A in human carcinogenesis.
Dual PI3K/mTOR inhibitor BEZ235 as a promising therapeutic strategy against paclitaxel-resistant gastric cancer via targeting PI3K/Akt/mTOR pathway
Authors: Chen Dongshao , Lin Xiaoting , Zhang Cheng , Liu Zhentao , Chen Zuhua , Li Zhongwu , Wang Jingyuan , Li Beifang , Hu Yanting , Dong Bin , Shen Lin , Ji Jiafu , Gao Jing , Zhang Xiaotian
Published: January 2018

Paclitaxel (PTX) is widely used in the front-line chemotherapy for gastric cancer (GC), but resistance limits its use. Due to the lack of proper models, mechanisms underlying PTX resistance in GC were not well studied. Using established PTX-resistant GC cell sublines HGC-27R, we for the first time integrated biological traits and molecular mechanisms of PTX resistance in GC. Data revealed that PTX-resistant GC cells were characterized by microtubular disorders, an EMT phenotype, reduced responses to antimitotic drugs, and resistance to apoptosis (marked by upregulated β-tubulin III, vimentin, attenuated changes in G2/M molecules or pro-apoptotic factors in response to antimitotic drugs or apoptotic inducers, respectively). Activation of the phosphoinositide 3-kinase, the serine/threonine kinase Akt and mammalian target of rapamycin (PI3K/Akt/mTOR) and mitogen-activated protein kinase (MAPK) pathways were also observed, which might be the reason for above phenotypic alternations. In vitro data suggested that targeting these pathways were sufficient to elicit antitumor responses in PTX-resistant GC, in which the dual PI3K/mTOR inhibitor BEZ235 displayed higher therapeutic efficiency than the mTOR inhibitor everolimus or the MEK inhibitor AZD6244. Antitumor effects of BEZ235 were also confirmed in mice bearing HGC-27R tumors. Thus, these data suggest that PI3K/Akt/mTOR and MAPK pathway inhibition, especially PI3K/mTOR dual blockade, might be a promising therapeutic strategy against PTX-resistant GC.
The responsively decreased PKM2 facilitates the survival of pancreatic cancer cells in hypoglucose
Authors: Li Xiang , Deng Shichang , Liu Mingliang , Jin Yan , Zhu Shuai , Deng Shijiang , Chen Jingyuan , He Chi , Qin Qi , Wang Chunyou , Zhao Gang
Published: January 2018

Cancer cells predominantly produce energy at a high rate of glycolysis even in aerobic environment. It is termed as Warburg effect and is necessary for the tumorigenesis. Studies showed pyruvate kinase M2 (PKM2), a key regulator of the Warburg effect, is overexpressed and involved in numerous cancers. However, the expression and function of PKM2 in pancreatic cancer (PC) remain undefined. Our results showed that PKM2 is overexpressed in the PC tissue compared to the peritumoral tissue. Unexpected, the downregulation of PKM2 did not affect the proliferation, invasion, and chemoresistance of PC cells. Since pancreatic cancer is a hypovascular tumor with comparably insufficient energy supply, we further investigate the relationship between PKM2 and hypoglucose. Interestingly, we further discovered that decreased expression of PKM2 was detected in PC samples with lower microvessel density as well as in PC cells treated with hypoglucose condition (0.5 mM). Furthermore, the downregulation of PKM2 facilitated, while the upregulation of PKM2 inhibited, PC cells survival during hypoglucose. We further revealed that the repressed PKM2 induced autophagy, high NADPH/NADP ratio, and biomacromolecule production, but reduced ROS accumulation. Moreover, AMPKα1 knockdown repressed the autophagy and survival of PC cells during hypoglucose, which were promoted by PKM2 knockdown. Collectively, our study indicates that decreased PKM2 diverts glucose metabolism to biomacromolecule accumulation and antioxidants generation during glucose deprivation. This metabolism alteration elevates AMPKα1-dependent autophagy, which facilitates PC cell survival during glucose deprivation. Therefore, functions of PKM2 are complicated and cannot be defined as oversimplified promoter or inhibitor in PC.
Desensitized chimeric antigen receptor T cells selectively recognize target cells with enhanced antigen expression
Authors: Han Chungyong , Sim Su-Jung , Kim Seon-Hee , Singh Rohit , Hwang Sunhee , Kim Yu I. , Park Sang H. , Kim Kwang H. , Lee Don G. , Oh Ho S. , Lee Sangeun , Kim Young H. , Choi Beom K. , Kwon Byoung S.
Published: January 2018

Chimeric antigen receptor (CAR) T cell therapy is an effective method for treating specific cancers. CARs are normally designed to recognize antigens, which are highly expressed on malignant cells but not on T cells. However, when T cells are engineered with CARs that recognize antigens expressed on the T cell surface, CAR T cells exhibit effector function on other T cells, which results in fratricide, or killing of neighboring T cells. Here, using human leukocyte antigen-DR (HLA-DR)-targeted CAR T cells, we show that weak affinity between CAR and HLA-DR reduces fratricide and induces sustained CAR downregulation, which consequently tunes the avidity of CAR T cells, leading to desensitization. We further demonstrate that desensitized CAR T cells selectively kill Epstein-Barr virus-transformed B cells with enhanced HLA-DR expression, while sparing normal B cells. Our study supports an avidity-tuning strategy that permits sensing of antigen levels by CAR T cells.
Differentiated surface fungal communities at point of harvest on apple fruits from rural and peri-urban orchards
Authors: Shen Youming , Nie Jiyun , Li Zhixia , Li Haifei , Wu Yonglong , Dong Yafeng , Zhang Jianyi
Published: January 2018

The diverse fungal communities that colonize fruit surfaces are closely associated with fruit development, preservation and quality control. However, the overall fungi adhering to the fruit surface and the inference of environmental factors are still unknown. Here, we characterized the fungal signatures on apple surfaces by sequencing internal transcribed spacer 1 (ITS1) region. We collected the surface fungal communities from apple fruits cultivated in rural and peri-urban orchards. A total of 111 fungal genera belonging to 4 phyla were identified, showing remarkable fungal diversity on the apple surface. Comparative analysis of rural samples harboured higher fungal diversity than those from peri-urban orchards. In addition, fungal composition varied significantly across apple samples. At the genus level, the protective genera Coniothyrium, Paraphaeosphaeria and Periconia were enriched in rural samples. The pathogenic genera Acremonium, Aspergillus, Penicillium and Tilletiposis were enriched in peri-urban samples. Our findings indicate that rural samples maintained more diverse fungal communities on apple surfaces, whereas peri-urban-planted apple carried potential pathogenic risks. This study sheds light on ways to improve fruit cultivation and disease prevention practices.
Periconception onset diabetes is associated with embryopathy and fetal growth retardation, reproductive tract hyperglycosylation and impaired immune adaptation to pregnancy
Authors: Brown Hannah M. , Green Ella S. , Tan Tiffany C. Y. , Gonzalez Macarena B. , Rumbold Alice R. , Hull M. Louise , Norman Robert J. , Packer Nicolle H. , Robertson Sarah A. , Thompson Jeremy G.
Published: January 2018

Diabetes has been linked with impaired fertility but the underlying mechanisms are not well defined. Here we use a streptozotocin-induced diabetes mouse model to investigate the cellular and biochemical changes in conceptus and maternal tissues that accompany hyperglycaemia. We report that streptozotocin treatment before conception induces profound intra-cellular protein β-O-glycosylation (O-GlcNAc) in the oviduct and uterine epithelium, prominent in early pregnancy. Diabetic mice have impaired blastocyst development and reduced embryo implantation rates, and delayed mid-gestation growth and development. Peri-conception changes are accompanied by increased expression of pro-inflammatory cytokine Trail, and a trend towards increased Il1a, Tnf and Ifng in the uterus, and changes in local T-cell dynamics that skew the adaptive immune response to pregnancy, resulting in 60% fewer anti-inflammatory regulatory T-cells within the uterus-draining lymph nodes. Activation of the heat shock chaperones, a mechanism for stress deflection, was evident in the reproductive tract. Additionally, we show that the embryo exhibits elevated hyper-O-GlcNAcylation of both cytoplasmic and nuclear proteins, associated with activation of DNA damage (ɣH2AX) pathways. These results advance understanding of the impact of peri-conception diabetes, and provide a foundation for designing interventions to support healthy conception without propagation of disease legacy to offspring.
Body ownership and the four-hand illusion
Authors: Chen Wen-Yeo , Huang Hsu-Chia , Lee Yen-Tung , Liang Caleb
Published: January 2018

Recent studies of the rubber hand illusion (RHI) have shown that the sense of body ownership is constrained by several factors and yet is still very flexible. However, exactly how flexible is our sense of body ownership? In this study, we address this issue by investigating the following question: is it possible that one may have the illusory experience of owning four hands? Under visual manipulation, the participant adopted the experimenter’s first-person perspective (1PP) as if it was his/her own. Sitting face to face, the participant saw four hands—the experimenter’s two hands from the adopted 1PP together with the subject’s own two hands from the adopted third-person perspective (3PP). We found that: (1) the four-hand illusion did not occur in the passive four-hand condition. (2) In the active four-hand condition, the participants tapped their index fingers, imitated by the experimenter. When tactile stimulations were not provided, the key illusion was not induced, either. (3) Strikingly, once all four hands began to act with the same pattern and received synchronous tactile stimulations at the same time, many participants felt as if they had two more hands. These results show that the sense of body ownership is much more flexible than most researchers have suggested.
Subclinical and overt hypothyroidism is associated with reduced glomerular filtration rate and proteinuria: a large cross-sectional population study
Authors: Chang Yi-Cheng , Chang Chia Hsuin , Yeh Yi-Chun , Chuang Lee-Ming , Tu Yu-Kang
Published: January 2018

Subclinical hypothyroidism has been associated with dyslipidemia, hypertension, and increased risk of coronary artery disease. However, limited is known for its effect on renal function. Here we aimed to investigate whether subclinical hypothyroidism is associated with reduced estimated glomerular filtration rate (eGFR) and proteinuria in the general population. A cross-sectional cohort of 74,356 adults aged ≥20 year participating in voluntary health examinations without previous thyroid diseases were recruited in Taiwan. The mean eGFR of persons with euthyroidism, subclinical, and overt hypothyroidism are 87.99, 83.46, and 72.22 mL/min/1.73 m2, respectively (P-for- trend < 0.001). The proportion of proteinuria in persons with euthyroidism, subclinical and overt hypothyroidism is 1.29%, 2.2%, and 2.97%, respectively (P-for-trend: 0.001). The odds ratio of CKD for subclinical, clinical, and all hypothyroidism is 2.04 (95% confidence interval (CI): 1.67-2.50) and 7.61 (95% CI: 4.92-11.77), and 2.41 (95% CI: 2.01–2.89), respectively as compared to euthyroidism. These odd ratios remained significant after further adjustments. The odds ratios for proteinuria is 2.04 (95% CI: 1.67–2.50), 7.61 (95% CI: 4.92–11.77), and 2.41 (95% CI: 2.01–2.89) for subclinical, clinical, and total hypothyroidism, respectively, although the odds ratios were attenuated after further adjustment. Our results suggest subclinical hypothyroidism is a novel risk factor of reduced renal function but not proteinuria.
The membrane tethered transcription factor EcbZIP17 from finger millet promotes plant growth and enhances tolerance to abiotic stresses
Authors: Ramakrishna Chopperla , Singh Sonam , Raghavendrarao Sangala , Padaria Jasdeep C. , Mohanty Sasmita , Sharma Tilak Raj , Solanke Amolkumar U.
Published: January 2018

The occurrence of various stresses, as the outcome of global climate change, results in the yield losses of crop plants. Prospecting of genes in stress tolerant plant species may help to protect and improve their agronomic performance. Finger millet (Eleusine coracana L.) is a valuable source of superior genes and alleles for stress tolerance. In this study, we isolated a novel endoplasmic reticulum (ER) membrane tethered bZIP transcription factor from finger millet, EcbZIP17. Transgenic tobacco plants overexpressing this gene showed better vegetative growth and seed yield compared with wild type (WT) plants under optimal growth conditions and confirmed upregulation of brassinosteroid signalling genes. Under various abiotic stresses, such as 250 mM NaCl, 10% PEG6000, 400 mM mannitol, water withdrawal, and heat stress, the transgenic plants showed higher germination rate, biomass, primary and secondary root formation, and recovery rate, compared with WT plants. The transgenic plants exposed to an ER stress inducer resulted in greater leaf diameter and plant height as well as higher expression of the ER stress-responsive genes BiP, PDIL, and CRT1. Overall, our results indicated that EcbZIP17 improves plant growth at optimal conditions through brassinosteroid signalling and provide tolerance to various environmental stresses via ER signalling pathways.
Dysregulated fibronectin trafficking by Hsp90 inhibition restricts prostate cancer cell invasion
Authors: Armstrong Heather K. , Gillis Joanna L. , Johnson Ian R. D. , Nassar Zeyad D. , Moldovan Max , Levrier Claire , Sadowski Martin C. , Chin Mei Yieng , Tomlinson Guns Emma S. , Tarulli Gerard , Lynn David J. , Brooks Douglas A. , Selth Luke A. , Centenera Margaret M. , Butler Lisa M.
Published: January 2018

The molecular chaperone Hsp90 is overexpressed in prostate cancer (PCa) and is responsible for the folding, stabilization and maturation of multiple oncoproteins, which are implicated in PCa progression. Compared to first-in-class Hsp90 inhibitors such as 17-allylamino-demethoxygeldanamycin (17-AAG) that were clinically ineffective, second generation inhibitor AUY922 has greater solubility and efficacy. Here, transcriptomic and proteomic analyses of patient-derived PCa explants identified cytoskeletal organization as highly enriched with AUY922 treatment. Validation in PCa cell lines revealed that AUY922 caused marked alterations to cell morphology, and suppressed cell motility and invasion compared to vehicle or 17-AAG, concomitant with dysregulation of key extracellular matrix proteins such as fibronectin (FN1). Interestingly, while the expression of FN1 was increased by AUY922, FN1 secretion was significantly decreased. This resulted in cytosolic accumulation of FN1 protein within late endosomes, suggesting that AUY922 disrupts vesicular secretory trafficking pathways. Depletion of FN1 by siRNA knockdown markedly reduced the invasive capacity of PCa cells, phenocopying AUY922. These results highlight a novel mechanism of action for AUY922 beyond its established effects on cellular mitosis and survival and, furthermore, identifies extracellular matrix cargo delivery as a potential therapeutic target for the treatment of aggressive PCa.
Internet Communication Disorder and the structure of the human brain: initial insights on WeChat addiction
Authors: Montag Christian , Zhao Zhiying , Sindermann Cornelia , Xu Lei , Fu Meina , Li Jialin , Zheng Xiaoxiao , Li Keshuang , Kendrick Keith M. , Dai Jing , Becker Benjamin
Published: January 2018

WeChat represents one of the most popular smartphone-based applications for communication. Although the application provides several useful features that simplify daily life, a growing number of users spend excessive amounts of time on the application. This may lead to interferences with everyday life and even to addictive patterns of use. In the context of the ongoing discussion on Internet Communication Disorder (ICD), the present study aimed to better characterize the addictive potential of communication applications, using WeChat as an example, by examining associations between individual variations in tendencies towards WeChat addiction and brain structural variations in fronto-striatal-limbic brain regions. To this end levels of addictive tendencies, frequency of use and structural MRI data were assessed in n = 61 healthy participants. Higher tendencies towards WeChat addiction were associated with smaller gray matter volumes of the subgenual anterior cingulate cortex, a key region for monitoring and regulatory control in neural networks underlying addictive behaviors. Moreover, a higher frequency of the paying function was associated with smaller nucleus accumbens volumes. Findings were robust after controlling for levels of anxiety and depression. The present results are in line with previous findings in substance and behavioral addictions, and suggest a similar neurobiological basis in ICD.
Thermally-triggered Dual In-situ Self-healing Metallic Materials
Authors: Kim JeongTae , Kim Hee Jin , Hong Sung Hwan , Park Hae Jin , Kim Young Seok , Hwang Yun Jung , Jeong Yeon Beom , Park Jun-Young , Park Jin Man , Sarac Baran , Wang Wei-Min , Eckert Jürgen , Kim Ki Buem
Published: January 2018

The microstructural evolution and crack filling phenomena of (Al81Cu13Si6)100−x(Sn57Bi43)
x
(x = 0, 1, and 3 at.%) composites was investigated. The Sn and Bi elements were selected by considering the ability for liquid phase separation when combined with Al, Cu, and Si. Because of liquid phase separation, both Al-Cu-Si-rich L1 and Sn-Bi-rich L2 phases separately solidified at different temperatures yielding a trimodal eutectic structure in the cast alloys. The Sn and Bi elements have high mobilities due to the large interface of the eutectic microstructure and tend to strongly diffuse towards higher strained region during heat treatment. Furthermore, the mobile Sn and Bi elements in the Al-Cu-Si-based bimodal eutectic structure evidently fill cracks during warm rolling at 423 K. These results reveal that the developed alloy system has simultaneously dual self-healing characteristics, derived from the both precipitated Sn-Bi-rich particles and low melting agent, and the proposed alloy design based on liquid phase separation provides a novel strategy for creating self-crack filling metallic materials.
Mapping Monthly Water Scarcity in Global Transboundary Basins at Country-Basin Mesh Based Spatial Resolution
Authors: Degefu Dagmawi Mulugeta , Weijun He , Zaiyi Liao , Liang Yuan , Zhengwei Huang , Min An
Published: January 2018

Currently fresh water scarcity is an issue with huge socio-economic and environmental impacts. Transboundary river and lake basins are among the sources of fresh water facing this challenge. Previous studies measured blue water scarcity at different spatial and temporal resolutions. But there is no global water availability and footprint assessment done at country-basin mesh based spatial and monthly temporal resolutions. In this study we assessed water scarcity at these spatial and temporal resolutions. Our results showed that around 1.6 billion people living within the 328 country-basin units out of the 560 we assessed in this study endures severe water scarcity at least for a month within the year. In addition, 175 country-basin units goes through severe water scarcity for 3–12 months in the year. These sub-basins include nearly a billion people. Generally, the results of this study provide insights regarding the number of people and country-basin units experiencing low, moderate, significant and severe water scarcity at a monthly temporal resolution. These insights might help these basins’ sharing countries to design and implement sustainable water management and sharing schemes.
Advanced Steel Microstructural Classification by Deep Learning Methods
Authors: Azimi Seyed Majid , Britz Dominik , Engstler Michael , Fritz Mario , Mücklich Frank
Published: January 2018

The inner structure of a material is called microstructure. It stores the genesis of a material and determines all its physical and chemical properties. While microstructural characterization is widely spread and well known, the microstructural classification is mostly done manually by human experts, which gives rise to uncertainties due to subjectivity. Since the microstructure could be a combination of different phases or constituents with complex substructures its automatic classification is very challenging and only a few prior studies exist. Prior works focused on designed and engineered features by experts and classified microstructures separately from the feature extraction step. Recently, Deep Learning methods have shown strong performance in vision applications by learning the features from data together with the classification step. In this work, we propose a Deep Learning method for microstructural classification in the examples of certain microstructural constituents of low carbon steel. This novel method employs pixel-wise segmentation via Fully Convolutional Neural Network (FCNN) accompanied by a max-voting scheme. Our system achieves 93.94% classification accuracy, drastically outperforming the state-of-the-art method of 48.89% accuracy. Beyond the strong performance of our method, this line of research offers a more robust and first of all objective way for the difficult task of steel quality appreciation.
Continuous cropping of endangered therapeutic plants via electron beam soil-treatment and neutron tomography
Authors: Sim Cheul Muu , Seong Bong Jae , Kim Dong Won , Kim Yong Bum , Wi Seung Gon , Kim Gyuil , Oh Hwasuk , Kim TaeJoo , Chung Byung Yeoup , Song Jeong Young , Kim Hong Gi , Oh Sang-Keun , Shin Young Dol , Seok Jea Hwan , Kang Min Young , Lee Yunhee , Radebe Mabuti Jacob , Kardjilov Nikolay , Honermeier Bernd
Published: January 2018

Various medicinal plants are threatened with extinction owing to their over-exploitation and the prevalence of soil borne pathogens. In this study, soils infected with root-rot pathogens, which prevent continuous-cropping, were treated with an electron beam. The level of soil-borne fungus was reduced to ≤0.01% by soil electron beam treatment without appreciable effects on the levels of antagonistic microorganism or on the physicochemical properties of the soil. The survival rate of 4-year-old plant was higher in electron beam-treated soil (81.0%) than in fumigated (62.5%), virgin (78%), or untreated-replanting soil (0%). Additionally, under various soils conditions, neutron tomography permitted the monitoring of plant health and the detection of root pathological changes over a period of 4–6 years by quantitatively measuring root water contentin situ. These methods allow continual cropping on the same soil without pesticide treatment. This is a major step toward the environmentally friendly production of endangered therapeutic herbs.