bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of forest clear cuts on plant–pollinator interactions: the case of three ericaceous subshrubs in Lithuanian pine forests
Authors: Daubaras Remigijus , Cesoniene Laima , Zych Marcin , Tamutis Vytautas , Stakėnas Vidas
Published: March 2017

Managed boreal pine forests are subject to regular clear cuts causing significant disturbances to these ecosystems. It is believed that, to some extent, they resemble natural cycles of forest growth, decline, and regeneration and can benefit, e.g., mutualistic relations among plants and pollinators. To study the impact of forest management (clear cuts) on pollinator visitation, we focused on three ericaceous plant species, Vaccinium myrtillus, V. vitis-idaea, and Calluna vulgaris, common elements of pine forest understory. Our observations, conducted in Lithuania, showed that there are no differences among control mature stands and clear cut areas in terms of visitation frequency for all three studied species. However, at least for C. vulgaris, a shift toward fly visits was observed in the clear cut site, showing that open areas are preferred habitats for these insects. Ants constituted an important share of visitors to flowers of V. myrtillus and C. vulgaris, suggesting their important role in reproduction of these plant species.
Epiphytic bacteria on lettuce affect the feeding behavior of an invasive pest slug
Authors: Peters Birte , Türke Manfred , Junker Robert R.
Published: March 2017

Plant–animal interactions are not isolated pairwise relationships but are always accompanied by diverse assemblages of microbes. Additional to direct effects of microorganisms on their hosts, recent investigations demonstrated that bacteria associated with plants can modify the behavior of organisms of higher trophic levels. However, in the context of herbivory, functions of non-phytopathogenic bacteria colonizing leaf surfaces remain understudied. This study showed that naturally occurring epiphytic bacteria affect the feeding behavior of a generalist herbivore. Epiphytic bacteria isolated from leaves of Lactuca sativa var. capitata were screened for their potential to influence feeding choices of the slug Arion vulgaris. Cultivated bacteria were inoculated in artificial food substrates or on sterile leaves of gnotobiotic lettuce plants and were offered to slugs in different behavioral bioassays. A large proportion of bacterial strains tested induced behavioral alterations in the feeding choices of slugs. Behavioral responses of slugs were further modified by antibiotic treatment of slugs prior to choice tests indicating that both bacteria associated with plants and animals affect plant–animal interactions. Our results emphasize the important role of bacteria in plant–animal interactions and suggest a prominent role of bacteria in herbivory in natural, horticultural, and agricultural systems.
Long-term growth performance and productivity of Scots pine (Pinus sylvestris L.) populations
Authors: Hebda Anna Maria , Wachowiak Witold , Skrzyszewski Jerzy
Published: March 2017

The phenotypic differentiation of 16 provenances of Scots pine originating from a wide variety of habitats that range from lowland to southern highland locations in Poland was assessed during 47 years of their growth and development in the Carpathian Mountains. The traits, including height, diameter at breast height, stem straightness, and crown width, were used to evaluate the differentiation of the provenances in their juvenile period and at maturity and were examined for patterns of local adaptation. The populations from northern Poland were characterized by the best growth and productivity, whereas provenances from central Poland had the best stem quality. There were some changes in growth between provenances observed during the experiment, but the stand volume (m3/ha) in juvenile trees was closely correlated with that in mature trees (r = 0.979). There was a positive relationship between the productivity and the environmental conditions of the geographical origin of provenances with increasing values for the trees’ productivity from south to north. Additionally, the elevation above sea level of the original populations was inversely correlated with the growth achieved by the progeny. In general, most populations from the species distribution range in Poland tested in the severe climate conditions of the Carpathian Mountains showed good growth performance under that environment, characterized by low temperatures and short growing periods. Provenances from climatic zones outside mountain regions demonstrated great growth and productivity, which proved to be the most important for competitively outperforming the local populations. Our study demonstrates good adaptive potential of the tested provenances, as selection will favor fast-growing genotypes under the predicted environmental change scenario.
Ethylene-dependent effects on generative organ abscission of Lupinus luteus
Authors: Frankowski Kamil , Kućko Agata , Zienkiewicz Agnieszka , Zienkiewicz Krzysztof , Alché Juan de Dios , Kopcewicz Jan , Wilmowicz Emilia
Published: March 2017

The abscission of certain organs from the plant is part of the fulfilment of its developmental programs. The separation process occurs in a specialized abscission zone usually formed at the base of detached organ. The changing level of phytohormones, particularly ethylene, is the element responsible for coordinating anatomical and physiological transformation that accompanies organ abscission. The application of ethylene (ET) on Lupinus luteus stimulates flower abortion. However, the treatment with 1-aminocyclopropane-1-carboxylic acid (ACC) – direct ET precursor – does not cause such a strong physiological response. In turn, when applied on the pedicels both ET biosynthesis (2-aminoethoxyvinylglycine; AVG) and action (norbornadiene; NBD) inhibitors reversed the stimulatory effect of ET on generative organ separation. In order to determine ET role in the flower abscission process in L. luteus, we identified the sequences coding for synthase (LlACS) and oxidase (LlACO) of ACC and measured their expression levels. Abscission zone activation is accompanied by a considerable increase both in LlACS and LlACO cDNAs and also ACC content, which is specifically localized in the dividing cells at the base of the flower being detached. Obtained results suggest that ET is a strong stimulator of flower abortion in L. luteus.
Deposition efficiency in the preparation of ozone-producing nickel and antimony doped tin oxide anodes
Authors: Sandin Staffan , Cheritat Alicia , Bäckström Joakim , Cornell Ann
Published: March 2017

The influence of precursor salts in the synthesis of nickel and antimony doped tin oxide (NATO) electrodes using thermal decomposition from dissolved chloride salts was investigated. The salts investigated were SnCl4×5H2O, SnCl2×2H2O, SbCl3 and NiCl2×6H2O. It was shown that the use of SnCl4×5H20 in the preparation process leads to a tin loss of more than 85 %. The loss of Sb can be as high as 90 % while no indications of Ni loss was observed. As a consequence, the concentration of Ni in the NATO coating will be much higher than in the precursor solution. This high and uncontrolled loss of precursors during the preparation process will lead to an unpredictable composition in the NATO coating and will have negative economic and environmental effects. It was found that using SnCl2×2H20 instead of SnCl4×5H2O can reduce the tin loss to less than 50 %. This tin loss occurs at higher temperatures than when using SnCl4×5H2O where the tin loss occurs from 56 – 147 °C causing the composition to change both during the drying (80 – 110 °C) and calcination (460 -550 °C) steps of the preparation process. Electrodes coated with NATO based on the two different tin salts were investigated for morphology, composition, structure, and ozone electrocatalytic properties.
The Significance of Lymphovascular Invasion of the Spermatic Cord in the Absence of Cord Soft Tissue Invasion
Authors: McCleskey Brandi C. , Epstein Jonathan I. , Albany Constantine , Hashemi-Sadraei Neda , Idrees Muhammad T. , Jorns Julie M. , Lu David Y. , Matoso Andres , Rais-Bahrami Soroush , Schwartz Lauren E. , Ulbright Thomas M. , Gordetsky Jennifer
Published: March 2017

Context.—

Testicular germ cell tumors with lymphovascular invasion (LVI) are staged pT2, and those with spermatic cord involvement are staged pT3.

Objective.—

To study the clinical significance of LVI within the spermatic cord without direct involvement of the cord soft tissues.

Design.—

A retrospective, multi-institutional review was performed on testicular GCTs with spermatic cord LVI in the absence of cord soft tissue invasion.

Results.—

Forty-four germ cell tumors had LVI in the spermatic cord without soft tissue invasion; 37 of 44 patients (84%) had nonseminomatous germ cell tumors (NSGCT), and 7 (16%) had pure seminomas. Patients with NSGCTs and spermatic cord LVI had worse clinical outcomes compared with patients with pure seminoma and spermatic cord LVI (P = .008). We then compared patients with NSGCTs and spermatic cord LVI (n = 37) to patients with NSGCTs and LVI limited to the testis (n = 32). A significantly greater percentage of patients with LVI in the spermatic cord presented with advanced clinical stage (76% versus 50%; P = .01). There was no statistically significant difference in disease recurrence/progression or death between patients with spermatic cord LVI and patients with LVI limited to the testis (P = .40; P = .50). There was no significant difference in the presence of embryonal dominant histology (P = .30) or rete testis invasion (P = .50) between the 2 groups. More hilar soft tissue invasion was seen in patients with LVI present in the spermatic cord (P = .004).

Conclusions.—

In patients with NSGCTs, LVI in the spermatic cord, without soft tissue invasion, is associated with worse clinical stage at presentation compared with patients with LVI confined to the testis.
Frequent exchange of the DNA polymerase during bacterial chromosome replication
Authors: Beattie Thomas R , Kapadia Nitin , Nicolas Emilien , Uphoff Stephan , Wollman Adam JM , Leake Mark C , Reyes-Lamothe Rodrigo
Published: March 2017

The replisome is a multiprotein machine that carries out DNA replication. In Escherichia coli, a single pair of replisomes is responsible for duplicating the entire 4.6 Mbp circular chromosome. In vitro studies of reconstituted E. coli replisomes have attributed this remarkable processivity to the high stability of the replisome once assembled on DNA. By examining replisomes in live E. coli with fluorescence microscopy, we found that the Pol III* subassembly frequently disengages from the replisome during DNA synthesis and exchanges with free copies from solution. In contrast, the DnaB helicase associates stably with the replication fork, providing the molecular basis for how the E. coli replisome can maintain high processivity and yet possess the flexibility to bypass obstructions in template DNA. Our data challenges the widely-accepted semi-discontinuous model of chromosomal replication, instead supporting a fully discontinuous mechanism in which synthesis of both leading and lagging strands is frequently interrupted.
Evolution of substrate specificity in a retained enzyme driven by gene loss
Authors: Juárez-Vázquez Ana Lilia , Edirisinghe Janaka N , Verduzco-Castro Ernesto A , Michalska Karolina , Wu Chenggang , Noda-García Lianet , Babnigg Gyorgy , Endres Michael , Medina-Ruíz Sofía , Santoyo-Flores Julián , Carrillo-Tripp Mauricio , Ton-That Hung , Joachimiak Andrzej , Henry Christopher S , Barona-Gómez Francisco
Published: March 2017

The connection between gene loss and the functional adaptation of retained proteins is still poorly understood. We apply phylogenomics and metabolic modeling to detect bacterial species that are evolving by gene loss, with the finding that Actinomycetaceae genomes from human cavities are undergoing sizable reductions, including loss of L-histidine and L-tryptophan biosynthesis. We observe that the dual-substrate phosphoribosyl isomerase A or priA gene, at which these pathways converge, appears to coevolve with the occurrence of trp and his genes. Characterization of a dozen PriA homologs shows that these enzymes adapt from bifunctionality in the largest genomes, to a monofunctional, yet not necessarily specialized, inefficient form in genomes undergoing reduction. These functional changes are accomplished via mutations, which result from relaxation of purifying selection, in residues structurally mapped after sequence and X-ray structural analyses. Our results show how gene loss can drive the evolution of substrate specificity from retained enzymes.
Role of D-aminoacyl-tRNA deacylase beyond chiral proofreading as a cellular defense against glycine mischarging by AlaRS
Authors: Pawar Komal Ishwar , Suma Katta , Seenivasan Ayshwarya , Kuncha Santosh Kumar , Routh Satya Brata , Kruparani Shobha P , Sankaranarayanan Rajan
Published: March 2017

Strict L-chiral rejection through Gly-cisPro motif during chiral proofreading underlies the inability of D-aminoacyl-tRNA deacylase (DTD) to discriminate between D-amino acids and achiral glycine. The consequent Gly-tRNAGly ‘misediting paradox’ is resolved by EF-Tu in the cell. Here, we show that DTD’s active site architecture can efficiently edit mischarged Gly-tRNAAla species four orders of magnitude more efficiently than even AlaRS, the only ubiquitous cellular checkpoint known for clearing the error. Also, DTD knockout in AlaRS editing-defective background causes pronounced toxicity in Escherichia coli even at low-glycine levels which is alleviated by alanine supplementation. We further demonstrate that DTD positively selects the universally invariant tRNAAla-specific G3•U70. Moreover, DTD’s activity on non-cognate Gly-tRNAAla is conserved across all bacteria and eukaryotes, suggesting DTD’s key cellular role as a glycine deacylator. Our study thus reveals a hitherto unknown function of DTD in cracking the universal mechanistic dilemma encountered by AlaRS, and its physiological importance.
A CDC25 family protein phosphatase gates cargo recognition by the Vps26 retromer subunit
Authors: Cui Tie-Zhong , Peterson Tabitha A , Burd Christopher G
Published: March 2017

We describe a regulatory mechanism that controls the activity of retromer, an evolutionarily conserved sorting device that orchestrates cargo export from the endosome. A spontaneously arising mutation that activates the yeast (Saccharomyces cerevisiae) CDC25 family phosphatase, Mih1, results in accelerated turnover of a subset of endocytosed plasma membrane proteins due to deficient sorting into a retromer-mediated recycling pathway. Mih1 directly modulates the phosphorylation state of the Vps26 retromer subunit; mutations engineered to mimic these states modulate the binding affinities of Vps26 for a retromer cargo, resulting in corresponding changes in cargo sorting at the endosome. The results suggest that a phosphorylation-based gating mechanism controls cargo selection by yeast retromer, and they establish a functional precedent for CDC25 protein phosphatases that lies outside of their canonical role in regulating cell cycle progression.
A type I IFN-dependent DNA damage response regulates the genetic program and inflammasome activation in macrophages
Authors: Morales Abigail J , Carrero Javier A , Hung Putzer J , Tubbs Anthony T , Andrews Jared M , Edelson Brian T , Calderon Boris , Innes Cynthia L , Paules Richard S , Payton Jacqueline E , Sleckman Barry P
Published: March 2017

Macrophages produce genotoxic agents, such as reactive oxygen and nitrogen species, that kill invading pathogens. Here we show that these agents activate the DNA damage response (DDR) kinases ATM and DNA-PKcs through the generation of double stranded breaks (DSBs) in murine macrophage genomic DNA. In contrast to other cell types, initiation of this DDR depends on signaling from the type I interferon receptor. Once activated, ATM and DNA-PKcs regulate a genetic program with diverse immune functions and promote inflammasome activation and the production of IL-1β and IL-18. Indeed, following infection with Listeria monocytogenes, DNA-PKcs-deficient murine macrophages produce reduced levels of IL-18 and are unable to optimally stimulate IFN-γ production by NK cells. Thus, genomic DNA DSBs act as signaling intermediates in murine macrophages, regulating innate immune responses through the initiation of a type I IFN-dependent DDR.
Ribonuclease L mediates the cell-lethal phenotype of double-stranded RNA editing enzyme ADAR1 deficiency in a human cell line
Authors: Li Yize , Banerjee Shuvojit , Goldstein Stephen A , Dong Beihua , Gaughan Christina , Rath Sneha , Donovan Jesse , Korennykh Alexei , Silverman Robert H , Weiss Susan R
Published: March 2017

ADAR1 isoforms are adenosine deaminases that edit and destabilize double-stranded RNA reducing its immunostimulatory activities. Mutation of ADAR1 leads to a severe neurodevelopmental and inflammatory disease of children, Aicardi-Goutiéres syndrome. In mice, Adar1 mutations are embryonic lethal but are rescued by mutation of the Mda5 or Mavs genes, which function in IFN induction. However, the specific IFN regulated proteins responsible for the pathogenic effects of ADAR1 mutation are unknown. We show that the cell-lethal phenotype of ADAR1 deletion in human lung adenocarcinoma A549 cells is rescued by CRISPR/Cas9 mutagenesis of the RNASEL gene or by expression of the RNase L antagonist, murine coronavirus NS2 accessory protein. Our result demonstrate that ablation of RNase L activity promotes survival of ADAR1 deficient cells even in the presence of MDA5 and MAVS, suggesting that the RNase L system is the primary sensor pathway for endogenous dsRNA that leads to cell death.
The alternative life of RNA—sequencing meets single molecule approaches
Authors: Fernández‐Moya Sandra M. , Ehses Janina , Kiebler Michael A.
Published: March 2017

The central dogma of RNA processing has started to totter. Single genes produce a variety of mRNA isoforms by mRNA modification, alternative polyadenylation (APA), and splicing. Different isoforms, even those that code for the identical protein, may differ in function or spatiotemporal expression. One option of how this can be achieved is by the selective recruitment of trans‐acting factors to the 3′‐untranslated region of a given isoform. Recent innovations in high‐throughput RNA‐sequencing methods allow deep insight into global RNA regulation, whereas novel imaging‐based technologies enable researchers to explore single RNA molecules during different stages of development, in different tissues and different compartments of the cell. Resolving the dynamic function of ribonucleoprotein particles in splicing, APA, or RNA modification will enable us to understand their contribution to pathological conditions.
Dissection of ubiquitinated protein degradation by basal autophagy
Authors: Takayama Kaori , Matsuura Akira , Itakura Eisuke
Published: March 2017

Basal autophagy plays an essential role as a protein quality control system. Although it has been demonstrated that the loss of autophagy results in the accumulation of ubiquitin‐positive aggregates and the development of neurodegenerative diseases, the precise autophagy substrate(s) remain unclear. Here, we determined whether ubiquitinated proteins are direct substrates for basal autophagy using a fluorescent ratiometric probe for ubiquitin. We show that the degradation of polyubiquitinated proteins is not dependent on basal autophagy. Although ubiquitin‐positive aggregates are observed in autophagy knockout cultured cells, the aggregates consist of soluble and mobile polyubiquitinated proteins, which are trapped by p62 without an increase in the total amount of ubiquitinated proteins. These results suggest that ubiquitinated proteins are not major targets for basal autophagy.
Control Variates
Authors: Lemieux Christiane
Published: March 2017

Monte Carlo simulation methods are widely used in several scientific disciplines. They are flexible and easy to apply, but their corresponding error is sometimes deemed too large. This error can be reduced by increasing the sample size, but a more effective approach is to apply cleverly designedvariance reduction techniques. Control variates is an example of such a technique. It aims at reducing the Monte Carlo estimator's variance using a correcting factor that depends on the distance between a control variate and its expectation. This article explains how to use this technique and why it works.
Fear of Movement and Associated Factors Among Adults With Symptomatic Knee Osteoarthritis
Authors: Gunn Alexander H. , Schwartz Todd A. , Arbeeva Liubov S. , Callahan Leigh F. , Golightly Yvonne , Goode Adam , Hill Carla H. , Huffman Kim , Iversen Maura D. , Pathak Ami , Taylor Shannon Stark , Allen Kelli D.
Published: March 2017

Objective

To examine the frequency of and factors associated with fear of movement (FOM) among patients with symptomatic knee osteoarthritis (KOA), using the new Brief Fear of Movement (BFOM) measure.

Methods

Participants (n = 350) enrolled in a clinical trial completed the BFOM scale prior to randomization. The relationships of BFOM with the following characteristics were examined: age, sex, race, education, pain and activities of daily living (ADL) subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS), knee symptom duration, depressive symptoms (8‐item Patient Health Questionnaire [PHQ‐8]), history of falls and knee injury, family history of knee problems, self‐efficacy for exercise (SEE), and unilateral balance test. A proportional odds logistic regression model examined multivariable associations of participant characteristics with a 3‐level BFOM variable (agreement with 0, 1–2, or ≥3 items).

Results

The majority of participants (77%) agreed with at least 1 item on the BFOM scale, and 36% endorsed 3+ items, suggesting a high degree of FOM. In the multivariable model, the following remained significant after backward selection: age (odds ratio [OR] 0.79 per 10‐point increase, 95% confidence interval [95% CI] 0.66–0.95), KOOS ADL (OR 0.86 per 10‐point increase, 95% CI 0.76–0.97), PHQ‐8 (OR 1.15, 95% CI 1.08–1.22), and SEE (OR 0.87 per 10‐point increase, 95% CI 0.78–0.96).

Conclusion

FOM was common among patients with symptomatic KOA, and this could negatively impact physical activity. Psychological variables were significantly associated with FOM, suggesting behavioral and psychological interventions may decrease FOM and improve outcomes among individuals with symptomatic KOA.
Resonant Tunneling through Monolayer Si Colloidal Quantum Dots and Ge Nanocrystals
Authors: Liao Yuanxun , Zhang Pengfei , Bremner Stephen , Shrestha Santosh , Huang Shujuan , Conibeer Gavin
Published: March 2017

Resonant tunneling through a 4 nm nanocrystal Ge (nc‐Ge) layer and a 2.4 nm monolayer of Si colloidal quantum dots (QD) is achieved with 0.7 nm amorphous Al2O3 (a‐Al2O3) barriers. The nc‐Ge resonant tunneling diode (RTD) demonstrates a peak‐to‐valley current ratio (PVCR) of 8 and a full width at half maximum (FWHM) of 30 mV at 300 K, the best performance among RTDs based on annealed nanocrystals. The Si QD RTD is first achieved with PVCRs up to 47 and FWHMs as small as 10 mV at room temperature, confirming theoretically expected excellences of 3D carrier confinements. The high performances are partially due to the smooth profile of nc‐Ge layer and the uniform distribution of Si QDs, which reduce the adverse influences of many‐body effects. More importantly, carrier decoherence is avoided in the 0.7 nm a‐Al2O3 barriers thinner than the phase coherence length (≈1.5 nm). Ultrathin a‐Al2O3 also passivates well materials and suppresses leakage currents. Additionally, the interfacial bandgap of ultrathin a‐Al2O3 is found to be similar to the bulk, forming deep potential wells to sharpen transmission curves. This work can be easily extended to other materials, which may enable resonant tunneling in various nanosystems for diverse purposes.
Assembly of Au Plasmonic Photothermal Agent and Iron Oxide Nanoparticles on Ultrathin Black Phosphorus for Targeted Photothermal and Photodynamic Cancer Therapy
Authors: Yang Dan , Yang Guixin , Yang Piaoping , Lv Ruichan , Gai Shili , Li Chunxia , He Fei , Lin Jun
Published: March 2017

Photodynamic therapy (PDT), as a minimally invasive and high‐efficiency anticancer approach, has received extensive research attention recently. Despite plenty of effort devoted to exploring various types of photodynamic agents with strong near‐infrared (NIR) absorbance for PDT and many encouraging progresses achieved in the area, effective and safe photodynamic photosensitizers with good biodegradability and biocompatibility are still highly expected. In this work, a novel nanocomposite has been developed by assembly of iron oxide (Fe3O4) nanoparticles (NPs) and Au nanoparticles on black phosphorus sheets (BPs@Au@Fe3O4), which shows a broad light absorption band and a photodegradable character. In vitro and in vivo assay indicates that BPs@Au@Fe3O4 nanoparticles are highly biocompatible and exhibit excellent tumor inhibition efficacy owing to a synergistic photothermal and photodynamic therapy mediated by a low‐power NIR laser. Importantly, BPs@Au@Fe3O4 can anticipatorily suppress tumor growth by visualized synergistic therapy with the help of magnetic resonance imaging (MRI). This work presents the first combination application of the photodynamic and photothermal effect deriving from black phosphorus nanosheets and plasmonic photothermal effect from Au nanoparticles together with MRI from Fe3O4 NPs, which may open the new utilization of black phosphorus nanosheets in biomedicine, optoelectronic devices, and photocatalysis.
Supersonically Sprayed Copper–Nickel Microparticles as Flexible and Printable Thin‐Film High‐Temperature Heaters
Authors: Lee Jong‐Gun , Kim Do‐Yeon , Kim Tae‐Gun , Lee Jong‐Hyuk , Al‐Deyab Salem S. , Lee Hyun Woo , Kim Jang Soo , Yang Dae Ho , Yarin Alexander L. , Yoon Sam S.
Published: March 2017

Cu and Ni nanoparticles are sprayed at supersonic velocities onto stiff glass, ceramic, and marble surfaces, as well as onto flexible polymer substrates of complex shapes. Joule heating occurs when a voltage is applied to the sprayed Cu–Ni thin films, enabling their use as thin‐film heaters. The Cu–Ni composition is varied to control the electrical and the thermal properties of the films, which affects the total amount of power used for the heating. At a high Cu content, the temperature reaches as high as 1000 °C, which significantly broadens the range of potential applications of such film heaters. The thermal stability of the film heaters is confirmed by cyclic testing, which shows repeatable rapid undulations in the temperature range of 600 °C. The Cu–Ni film heaters can be printed on any type of substrates including mirrors, glasses, and flexible polymers, and the method of film fabrication is rapid and scalable. The surface temperature of the heater is measured experimentally and matches well with the theoretical predictions. The Cu–Ni film heaters find applications in vehicle defrosters, smart heat‐retaining windows, domestic appliances, etc., and industrial heating and defrosting of complex surfaces.
Origin of Capacity Increasing in a Long‐Life Ternary Sn–Fe3O4@Graphite Anode for Li‐Ion Batteries
Authors: Zhang Hanyin , Hu Renzong , Liu Yuxuan , Liu Jiangwen , Lu Zhongchen , Zhu Min
Published: March 2017

The electrode–electrolyte interface plays a key role in the energy density and safety of the Li‐ion battery. The interfaces evolution induces the capacity increasing in many metal oxide anodes and attracts much attention. Here, the origin of the capacity increasing is verified by our long‐life Sn–Fe3O4@graphite composite anode. By analyzing the electrochemical curves, the Coulombic efficiency and interface/surface chemistry, the capacity increasing comes from the formation and dissolution of growing solid electrolyte interphase (SEI). The dissolution process only happens in certain high potential and under the effect of the sufficient nanosized metal particles with high electrocatalysis. The formation/dissolution of SEI is partial reversible to promote the conversion of the components in SEI. This conversion causes the Li+ irreversible consuming, but also favors the kinetics of the composite anode in the battery system.
Robust and Flexible Carbon Nanofibers Doped with Amine Functionalized Carbon Nanotubes for Efficient CO2 Capture
Authors: Iqbal Nousheen , Wang Xianfeng , Yu Jianyong , Ding Bin
Published: March 2017

Porous carbon nanofibrous materials have great potential for energy‐efficient CO2 capture and separations, but a major hurdle is the lack of mechanical strength and flexibility. Herein, the authors report a facile strategy for the fabrication of amine functionalized carbon nanotube (NC) doped carbon nanofibers (CNFs) (denoted as NC@CNFs) with high flexibility and hierarchical porosity. The NC@CNFs are used as robust fibrous adsorption materials for CO2 capture, which achieve superior CO2 uptake of 6.3 mmol g−1 at 1.0 bar and 298 K, as well as remarkable CO2/N2 selectivity and excellent cyclability. Integrating NC into CNFs not only brings number of adsorption sites (i.e., NH2) and tunable hierarchical pores for CO2 uptake, but also serves as single‐fiber‐crack connection to prevent NC@CNFs from brittle fracture. More significantly, the flexible NC@CNFs with highly stable structure and mechanical strength can overcome the limitation of easy pulverization and structure collapses for traditional particle‐shaped solid sorbents, which makes them highly operable and applicable. This work paves the way for a new route to produce fibrous textile materials with high flexibility and outstanding performance for gas separation.
Functional monosomy of 6q27‐qter and functional disomy of Xpter‐p22.11 due to X;6 translocation with an atypical X‐inactivation pattern
Authors: Podolska Anna , Kobelt Albrecht , Fuchs Sigrid , Hackmann Karl , Rump Andreas , Schröck Evelin , Kutsche Kerstin , Di Donato Nataliya
Published: March 2017

Pattern of X chromosome inactivation (XCI) is typically random in females. However, chromosomal rearrangements affecting the X chromosome can result in XCI skewing due to cell growth disadvantage. In case of an X;autosome translocation, this usually leads to an XCI pattern of 100:0 with the derivative X being the active one in the majority of females. A de novo balanced X;6 translocation [46,X,t(X;6)(p22.1;q27)] and a completely skewed XCI pattern (100:0) were detected in a female patient with microcephaly, cerebellar vermis hypoplasia, heart defect, and severe developmental delay. We mapped the breakpoint regions using fluorescence in situ hybridization and found the X‐linked gene POLA1 to be disrupted. POLA1 codes for the catalytic subunit of the polymerase α‐primase complex which is responsible for initiation of the DNA replication process; absence of POLA1 is probably incompatible with life. Consequently, by RBA banding we determined which of the X chromosomes was the active one in the patient. In all examined lymphocytes the wild‐type X chromosome was active. We propose that completely skewed XCI favoring the normal X chromosome resulted from death of cells with an active derivative X that was caused by a non‐functional POLA1 gene. In summary, we conclude that functional monosomy of 6q27‐qter and functional disomy of Xpter‐p22.11 are responsible for the clinical phenotype of the patient. This case demonstrates the importance of determining which one of the X chromosomes underwent inactivation to correlate clinical features of a female with an X;autosome translocation with the nature of the genetic alteration.
Asymmetric [4+2] Annulation of C1 Ammonium Enolates with Copper‐Allenylidenes
Authors: Song Jin , Zhang Zi‐Jing , Gong Liu‐Zhu
Published: March 2017

An asymmetric catalytic decarboxylative [4+2] annulation of 4‐ethynyl dihydrobenzooxazinones and carboxylic acids has been established by cooperative copper and nucleophilic Lewis base catalysis. A C1 ammonium enolate and copper–allenylidene complex, each catalytically generated from different substrates, underwent a cascade asymmetric propargylation and lactamization process to yield optically active 3,4‐dihydroquinolin‐2‐one derivatives with excellent levels of stereoselectivity (up to 99 % ee, 95:5 d.r.).
An Annulative Synthetic Strategy for Building Triphenylene Frameworks by Multiple C−H Bond Activations
Authors: Mathew Bijoy P. , Yang Hyun Ji , Kim Joohee , Lee Jae Bin , Kim Yun‐Tae , Lee Sungmin , Lee Chang Young , Choe Wonyoung , Myung Kyungjae , Park Jang‐Ung , Hong Sung You
Published: March 2017

C−H activation is a versatile tool for appending aryl groups to aromatic systems. However, heavy demands on multiple catalytic cycle operations and site‐selectivity have limited its use for graphene segment synthesis. A Pd‐catal‐ yzed one‐step synthesis of functionalized triphenylene frameworks is disclosed, which proceeds by 2‐ or 4‐fold C−H arylation of unactivated benzene derivatives. A Pd2(dibenzylideneacetone)3 catalytic system, using cyclic diaryliodonium salts as π‐extending agents, leads to site‐selective inter‐ and intramolecular tandem arylation sequences. Moreover, N‐substituted triphenylenes are applied to a field‐effect transistor sensor for rapid, sensitive, and reversible alcohol vapor detection.
Struktur und Biosynthese der Isatropolone, bioaktiver und Amin‐reaktiver fluoreszierender Naturstoffe aus Streptomyces Gö66
Authors: Cai Xiaofeng , Shi Yi‐Ming , Pöhlmann Nicole , Revermann Ole , Bahner Isabel , Pidot Sacha J. , Wesche Frank , Lackner Helmut , Büchel Claudia , Kaiser Marcel , Richter Christian , Schwalbe Harald , Stinear Timothy P. , Zeeck Axel , Bode Helge B.
Published: March 2017

Die Naturstoffe Isatropolon A–C (1–3) wurden aus Streptomyces Gö66 reisoliert, und insbesondere 1 und 3 zeigen sehr gute Aktivität gegen Leishmania donovani. Sie tragen einen ungewöhnlichen Tropolonring, der über einen Typ‐II‐Polyketid‐Biosyntheseweg aufgebaut wird. Ihre Biosynthese wurde mithilfe von Markierungsexperimenten, einer Analyse des Biosynthese‐Genclusters, heterologer Expression des Hauptteils des Genclusters und strukturelle Charakterisierung verschiedener Intermediate aufgeklärt. Aufgrund eines 1,5‐Diketon‐Strukturelementes können die Isatropolone mit Ammoniak und Aminen und insbesondere Lysin sowie Lysin‐tragenden Peptiden und Proteinen reagieren und einen Pyridinring bilden. Dabei ändern sich die Fluoreszenz‐Eigenschaften so deutlich, dass die so markierten Peptide und Proteine sehr einfach sichtbar gemacht werden können.
Formation of an Isolable Divinylborinium Ion through Twofold 1,2‐Carboboration between a Diarylborinium Ion and Diphenylacetylene
Authors: Tanaka Naoki , Shoji Yoshiaki , Hashizume Daisuke , Sugimoto Manabu , Fukushima Takanori
Published: March 2017

Borinium ions, that is, two‐coordinate boron cations, are the most electron‐deficient isolable boron compounds. As borinium ions have only four formal valence electrons on boron, they should show a strong tendency to accept electron pairs on the boron atom to fill its valence shell. Thus chemical reactions of borinium ions are expected to give products in which the coordination number of boron is increased from two to three or four. However, contrary to this expectation, we found that the dimesitylborinium ion (Mes2B+) undergoes twofold 1,2‐carboboration reactions with two equivalents of diphenylacetylene to yield an unprecedented borinium ion (1+) with two substituted vinyl groups on the boron center. NMR spectroscopy and X‐ray diffraction analysis of 1+, together with electronic‐structure calculations, revealed that the positive charge is delocalized over the entire π‐conjugated system. The fact that the chemical transformation of a borinium ion gives rise to a different borinium ion without a change in the coordination number is remarkable and should provide new insight into the chemistry of the Group 13 elements.
Structure and Biosynthesis of Isatropolones, Bioactive Amine‐Scavenging Fluorescent Natural Products from Streptomyces Gö66
Authors: Cai Xiaofeng , Shi Yi‐Ming , Pöhlmann Nicole , Revermann Ole , Bahner Isabel , Pidot Sacha J. , Wesche Frank , Lackner Helmut , Büchel Claudia , Kaiser Marcel , Richter Christian , Schwalbe Harald , Stinear Timothy P. , Zeeck Axel , Bode Helge B.
Published: March 2017

The natural products isatropolone A–C (1–3) were reisolated from Streptomyces Gö66, with 1 and 3 showing potent activity against Leishmania donovani. They contain a rare tropolone ring derived from a type II polyketide biosynthesis pathway. Their biosynthesis was elucidated by labeling experiments, analysis of the biosynthesis gene cluster, its partial heterologous expression, and structural characterization of various intermediates. Owing to their 1,5‐diketone moiety, they can react with ammonia, amines, lysine, and lysine‐containing peptides and proteins, which results in the formation of a covalent bond and subsequent pyridine ring formation. Their fluorescence properties change upon amine binding, enabling the simple visualization of reacted amines including proteins.
A facile one‐step synthesis of flame‐retardant coatings on cotton fabric via ultrasound irradiation
Authors: Liang Tianyuan , Jiang Zhenlin , Wang Chaosheng , Liu Jialin
Published: March 2017

This article reports a facile one‐step methodology to increase fire resistance properties of cotton fabric. The flame‐retardant coating for cotton fabric was synthesized with methyltriethoxysilane and organophosphates (M102B) through an ultrasound irradiation process. The coating structure and surface morphology of uncoated and coated fabrics were investigated by Fourier transform infrared spectroscopy and scanning electron microscope, respectively. The flame‐retardant properties, bending modulus, air permeability and thermal stability were studied by vertical burning test, cantilever method, air permeability test and thermogravimetric analysis (TGA). As a result, the cotton fabric coated with 29.2% (mass increased) of flame‐retardant coating was able to balance the flame retardant property and wearing comfort of the fabrics. The TGA results showed that the residue char of cotton was greatly enhanced after treatment with the coating, which has a high char forming effect on cellulose during testing. Furthermore, flame‐retardant property of coated fabrics did not change significantly after 10 washing cycles. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45114.
Improved cell morphology and thermal properties of expanded polypropylene beads by the addition of PP with a high melting point
Authors: Zhang Rong , Xiong Yezhi , Liu Qingting , Hu Shengfei
Published: March 2017

Expanded polypropylene (EPP) beads have attracted attention in recent years due to their potential use in fabricating complex, three dimensional structures. In this study, a small amount of polypropylene (PP) with a higher melting temperature (HPP) was blended with low melting point PP (LPP) to regulate the cell morphology and thermal behavior peaks of the resulting blends. These materials were then foamed to produce EPP beads in an autoclave with CO2 at different temperatures, producing EPP beads. The rheological, thermal, and foaming properties of the LPP/HPP blends were characterized. The melt strength and elasticity of LPP/HPP were improved because of rapid crystallization and increase in crystal number with increasing HPP content. These results were attributed to the physical crosslinks and nucleation sites provided by the HPP. These enhanced properties were leveraged to produce regular foams without through‐holes, decreased cell size, and increased cell density. Furthermore, the lower melting point decreased with increasing HPP content, producing a wider temperature range over which steam‐chest molding could occur. Thus, the addition of HPP is a facile method for regulating the cell morphology and thermal behavior of EPP. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45121.
Factors driving spatial variation in egg survival of an ecologically and culturally important forage fish
Authors: Keeling Britt , Hessing‐Lewis Margot , Housty Clark , Okamoto Daniel K. , Gregr Edward J. , Salomon Anne K.
Published: March 2017

Low trophic‐level forage fish are experiencing global declines, influencing coupled human–ocean systems worldwide. Along the northwest coast of North America, declining trajectories of Pacific herring (Clupea pallasii) have prompted interest in improving the understanding of its population and community dynamics to better guide future conservation and management strategies.

To improve future population estimates and understanding of the ecological factors governing herring egg survival, the magnitude, spatial variation and mechanisms driving herring egg loss rates were quantified. This was achieved by way of repeated observational field surveys and a predator exclusion experiment.

Observational surveys revealed that regional egg loss rates (Z) were substantial and ranged from 0.101 ± 0.019 to 0.134 ± 0.028, the equivalent of 88–94% egg loss over a 21 day incubation period, or 50–60% egg loss over 6.8 days, the average time lag between spawn deposition and annual egg surveys. Furthermore, spatial variation was high, with egg loss rates varying 5‐fold among study sites. Depth, time since spawn, and spawn area were primary spatial drivers of egg loss, but predator abundance and exposure were secondarily important.

Experimental evidence showed that benthic predation and habitat type were strong drivers of egg loss, suggesting that a high proportion of eggs, particularly those spawned on benthic substrates, are consumed by predators.

These results have important conservation implications for managers and ecologists seeking to estimate herring biomass and to understand the environmental influences on predator–prey interactions that affect herring dynamics.
Invasive Chinese pond mussel Sinanodonta woodiana threatens native mussel reproduction by inducing cross‐resistance of host fish
Authors: Donrovich Seth W. , Douda Karel , Plechingerová Věra , Rylková Kateřina , Horký Pavel , Slavík Ondřej , Liu Huan‐Zhang , Reichard Martin , Lopes‐Lima Manuel , Sousa Ronaldo
Published: March 2017

The effects of invasive alien species (IAS) on host–affiliate relationships are often subtle and remain unnoticed or insufficiently quantified. The global decline of freshwater unionid mussel species has been attributed to many causes, but little is known about the interactions of IAS, with their complex life cycle, which includes an obligatory parasitic stage (the glochidium) that develops on fishes.

The capacity of a European freshwater mussel, Anodonta anatina, to develop on its widespread fish host, Squalius cephalus was tested experimentally, after previous infestations by the IAS, Sinanodonta (Anodonta) woodiana. The initial attachment of glochidia, the length of the parasitic period, and the metamorphosis success rate of A. anatina glochidia were compared among treatments of different priming infestation intensities.

The metamorphosis success rate of the native A. anatina glochidia was strongly reduced (Wilcoxon Signed‐Rank Test, P < 0.001) and declined by 42.1 and 45.4% on fish hosts that were previously exposed to S. woodiana by single and multiple priming infestations, respectively, in comparison with the control group. Such cross‐resistance is expected to decrease significantly the quality of the host resources available to native mussels.

This study provides the first evidence of the host‐mediated adverse impact of invasive S. woodiana on native mussel species. These results also highlight the importance of potential competition for hosts between threatened groups of affiliate species and their invasive counterparts, which should be reflected in conservation strategies.
Assessing the impacts of tourism on the world's largest fish Rhincodon typus at Panaon Island, Southern Leyte, Philippines
Authors: Araujo Gonzalo , Vivier Fabien , Labaja Jessica June , Hartley Daniel , Ponzo Alessandro
Published: March 2017

Shark‐based tourism is a rapidly growing industry, particularly with whale sharks, as new hotspots are identified worldwide. Understanding any impacts of tourism is essential to minimize any potential detrimental effects on the target species and habitat.

In‐water behavioural observations of whale sharks were used to understand any impacts of tourism at a small site in Panaon Island, Southern Leyte, Philippines. A generalized linear mixed model was fitted to test anthropogenic and environmental variables, with interaction duration as the response variable, to assess any disturbance to the animals by the tourism activities.

Whale sharks were observed between the months of November and June between 2013 and 2016, with highly variable seasons. In total, 527 tourist‐whale shark interactions were recorded during 359 trips identifying 104 individual whale sharks, most of which were juvenile males (85%, measuring c. 5.5 m total length). Proximity of motorized vessels and interactions in deeper waters were found to significantly shorten interactions. Short‐term behavioural changes were observed in response to human events (e.g. touching). Interactions when whale sharks were feeding were significantly longer than when they were not. Individual behavioural variability was observed.

Impacts could be mitigated with small managerial changes and increased enforcement, such as limiting the number of motorized vessels and the number of people around the whale sharks. Although no long‐term impacts were recorded during this study, it is difficult to ascertain this in a long‐lived, wide‐ranging species.

This knowledge gap highlights the need to build long‐term monitoring programmes, and to apply the precautionary principle for the sustainable use of this endangered species.
Time limits in testing: An analysis of eye movements and visual attention in spatial problem solving
Authors: Roach Victoria A. , Fraser Graham M. , Kryklywy James H. , Mitchell Derek G.V. , Wilson Timothy D.
Published: March 2017

Individuals with an aptitude for interpreting spatial information (high mental rotation ability: HMRA) typically master anatomy with more ease, and more quickly, than those with low mental rotation ability (LMRA). This article explores how visual attention differs with time limits on spatial reasoning tests. Participants were assorted to two groups based on their mental rotation ability scores and their eye movements were collected during these tests. Analysis of salience during testing revealed similarities between MRA groups in untimed conditions but significant differences between the groups in the timed one. Question‐by‐question analyses demonstrate that HMRA individuals were more consistent across the two timing conditions (κ = 0.25), than the LMRA (κ = 0.013). It is clear that the groups respond to time limits differently and their apprehension of images during spatial problem solving differs significantly. Without time restrictions, salience analysis suggests LMRA individuals attended to similar aspects of the images as HMRA and their test scores rose concomitantly. Under timed conditions however, LMRA diverge from HMRA attention patterns, adopting inflexible approaches to visual search and attaining lower test scores. With this in mind, anatomical educators may wish to revisit some evaluations and teaching approaches in their own practice. Although examinations need to evaluate understanding of anatomical relationships, the addition of time limits may induce an unforeseen interaction of spatial reasoning and anatomical knowledge. Anat Sci Educ 10: 528–537. © 2017 American Association of Anatomists.