bluuebunny/crossref_metadata_2025 huggingface dataset:
Cellular function given parametric variation in the Hodgkin and Huxley model of excitability
Authors: Ori Hillel , Marder Eve , Marom Shimon
Published: August 2018

Significance

Macroscopic cellular function is maintained despite extensive variations in underlying elementary constituents, including the size of the cell, and the number, distribution, and kinetics of their proteins. Here, we take advantage of the sound theoretical and experimental basis of action potential generation to analyze macroscopic cellular invariance given microscopic variation. This analysis points to a significant gap between the high-dimensional level of description captured by biophysical measurements of channel function and the lower, physiological dimensionality, to which cellular function is sensitive. When examined in a lower dimension, a simple rule that relies on sodium channel slow inactivation provides a powerful homeostatic control mechanism that maintains excitability amid changes in protein concentrations and their kinetics.
HD 149277: a rare short-period SB2 system with a subsynchronously rotating magnetic He-rich primary
Authors: González J F , Hubrig S , Järvinen S P , Schöller M
Published: August 2018

HD 149277 is a rare SB2 system with a slowly rotating magnetic He-rich primary with Prot = 25.4 d. The CFHT/ESPaDOnS archive spectra revealed Porb = 11.5192 ± 0.0005 d indicating strong subsynchronous rotation of the primary component. Such a strong subsynchronous rotation was not detected in any other SB2 system with a magnetic chemically peculiar component. Our inspection of the spectra revealed the presence of resolved Zeeman split spectral lines allowing us to determine the variability of the mean magnetic field modulus over the rotation period. The maximum of the magnetic field modulus coincides roughly with the positive extremum of the longitudinal field, whereas the minimum of the modulus with the negative extremum of the longitudinal field. No evidence for a longitudinal magnetic field was seen in the circularly polarized spectra of the secondary component. Using archival data from the ASAS3 survey, we find in the frequency spectrum only one significant peak, corresponding to the period Pphot = 25.390 ± 0.014 d. This value is in good agreements with the previous determination of the rotation period, Prot = 25.380 ± 0.007 d, which was based on longitudinal magnetic field measurements.
How does human motor cortex regulate vocal pitch in singers?
Authors: Belyk Michel , Lee Yune S. , Brown Steven
Published: August 2018

Vocal pitch is used as an important communicative device by humans, as found in the melodic dimension of both speech and song. Vocal pitch is determined by the degree of tension in the vocal folds of the larynx, which itself is influenced by complex and nonlinear interactions among the laryngeal muscles. The relationship between these muscles and vocal pitch has been described by a mathematical model in the form of a set of ‘control rules’. We searched for the biological implementation of these control rules in the larynx motor cortex of the human brain. We scanned choral singers with functional magnetic resonance imaging as they produced discrete pitches at four different levels across their vocal range. While the locations of the larynx motor activations varied across singers, the activation peaks for the four pitch levels were highly consistent within each individual singer. This result was corroborated using multi-voxel pattern analysis, which demonstrated an absence of patterned activations differentiating any pairing of pitch levels. The complex and nonlinear relationships between the multiple laryngeal muscles that control vocal pitch may obscure the neural encoding of vocal pitch in the brain.
Room-temperature excitonic emission with a phonon replica from graphene nanosheets deposited on Ni-nanocrystallites/Si-nanoporous pillar array
Authors: Tang Zhaojun , Xu Tingting , Li Sen , Shi Zhifeng , Li Xinjian
Published: August 2018

Graphene nanosheets (GNSs) were grown on a Si nanoporous pillar array (Si-NPA) via chemical vapour deposition, using a thin layer of pre-deposited Ni nanocrystallites as catalyst. GNSs were determined to be of high quality and good dispersivity, with a typical diameter size of 15 × 8 nm. Light absorption measurements showed that GNSs had an absorption band edge at 3.3 eV. They also showed sharp and regular excitonic emitting peaks in the ultraviolet and visible region (2.06–3.6 eV). Moreover, phonon replicas with long-term stability appeared with the excitonic peaks at room temperature. Temperature-dependent photoluminescence from the GNSs revealed that the excitonic emission derived from free and bound excitonic recombination. A physical model based on band energy theory was constructed to analyse the carrier transport of GNSs. The Ni nanocrystallites on Si-NPA, which acted as a metal-enhanced fluorescence substrate, were supposed to accelerate the excitonic recombination of GNSs and enhanced the measured emission intensity. Results of this study would be valuable in determining the luminescence mechanism of GNSs and could be applied in real-world optoelectronic devices.
Inhibition mechanism of Ca
2+
, Mg
2+
and Fe
3+
in fine cassiterite flotation using octanohydroxamic acid
Authors: Ren Liuyi , Qiu Hang , Qin Wenqing , Zhang Ming , Li Yubiao , Wei Penggang
Published: August 2018

The existence of metal ions should not be ignored in both hydrometallurgy and flotation. In this study, the effects of Ca
2+
, Mg
2+
and Fe
3+
on the flotation performance of cassiterite using octanohydroxamic acid (OHA) as the collector were investigated by micro-flotation tests, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, contact angle, zeta (
ζ
) potential measurements and atomic force microscopy (AFM) imaging. The results of the flotation and contact angle experiments showed that the addition of Ca
2+
, Mg
2+
and Fe
3+
significantly decreased both the recovery and contact angle of cassiterite with pH ranged from 6.0 to 12.0 in the presence of OHA collector.
ζ-
Potential measurements, solution chemistry analysis and FTIR measurements indicated that the flotation recovery of the cassiterite declined due to the CaOH
+
, MgOH
+
and Fe(OH)
3
sites on the cassiterite surface. XPS results indicated that the chemisorption of OHA and calcium ions on the cassiterite surface finally changed its chemical properties. The AFM images also revealed that new species Fe(OH)
3
of Fe
3+
formed and adsorbed on the cassiterite surface at pH 9.0. The adsorption of Fe(OH)
3
reduced the adsorption of OHA on the cassiterite surface, thus the hydrophobicity of cassiterite was deteriorated.
Decorating gold nanostars with multiwalled carbon nanotubes for photothermal therapy
Authors: Zhu Yuting , Sun Quanmei , Liu Yingzhu , Ma Tao , Su Lei , Liu Sidi , Shi Xiaoli , Han Dong , Liang Feng
Published: August 2018

Gold nanoparticles and carbon nanotubes have attracted substantial attention in recent years for their potential applications in photothermal therapy (PTT) as an emerging breakthrough in cancer treatment. Herein, a hybrid nanomaterial of gold nanostars/multiwalled carbon nanotubes (MWCNTs) was synthesized by two-step reduction via the control of several synthetic conditions such as the reducing agent, pH value, concentration and ratio of reagents. The material shows good biocompatibility and high photothermal conversion efficiency, demonstrating its applicability in PTT. The lack of surfactant in the synthesis process made the hybrid nanomaterial cell-friendly, with no effects on viability
in vitro
. The MWCNT/gold nanostars hybrid nanomaterial presented 12.4% higher photothermal efficiency than gold nanostars alone and showed a 2.4-fold increase over gold nanospheres based on a heating test under 808 nm laser irradiation. Moreover, the MWCNTs/gold nanostars at low concentration (0.32 nM) exhibited remarkably improved photothermal cancer cell-killing efficacy, which may be attributed to the surface plasmon resonance absorption of the gold nanostars and the combined effects of enhanced coupling between the MWCNTs and gold nanostars. Collectively, these results demonstrate that the MWCNTs/gold nanostars developed herein show prominent photothermal value, and thus may serve as a novel photothermal agent for cancer therapy.
Influences of transversely isotropic rheology and translational diffusion on the stability of active suspensions
Authors: Holloway C. R. , Cupples G. , Smith D. J. , Green J. E. F. , Clarke R. J. , Dyson R. J.
Published: August 2018

Suspensions of self-motile, elongated particles are a topic of significant current interest, exemplifying a form of ‘active matter’. Examples include self-propelling bacteria, algae and sperm, and artificial swimmers. Ericksen's model of a transversely isotropic fluid (Ericksen 1960
Colloid Polym. Sci.
173
, 117–122 (
doi:10.1007/bf01502416
)) treats suspensions of non-motile particles as a continuum with an evolving preferred direction; this model describes fibrous materials as diverse as extracellular matrix, textile tufts and plant cell walls. Director-dependent effects are incorporated through a modified stress tensor with four viscosity-like parameters. By making fundamental connections with recent models for active suspensions, we propose a modification to Ericksen's model, mainly the inclusion of self-motility; this can be considered the simplest description of an oriented suspension including transversely isotropic effects. Motivated by the fact that transversely isotropic fluids exhibit modified flow stability, we conduct a linear stability analysis of two distinct cases, aligned and isotropic suspensions of elongated active particles. Novel aspects include the anisotropic rheology and translational diffusion. In general, anisotropic effects increase the instability of small perturbations, while translational diffusion stabilizes a range of wave-directions and, in some cases, a finite range of wavenumbers, thus emphasizing that both anisotropy and translational diffusion can have important effects in these systems.
New insight into the adsorption behaviour of effluent organic matter on organic–inorganic ultrafiltration membranes: a combined QCM-D and AFM study
Authors: Wang Xudong , Huang Danxi , Cheng Botao , Wang Lei
Published: August 2018

Adsorption of organic matter on membranes plays a major role in determining the fouling behaviour of membranes. This study investigated effluent organic matter (EfOM) adsorption behaviour onto poly(vinylidene fluoride) (PVDF) membrane blended with SiO
2
nanoparticles using quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). The QCM-D results suggested that low adsorption of EfOM and an EfOM layer with a non-rigid and open structure was formed on SiO
2
-terminated membrane surfaces. Conformational assessment showed that EfOM undergoes adsorption via two steps: (i) in the initial stage, a rapid adsorption of EfOM accumulated onto the membrane; (ii) the change in dissipation was still occurring when the adsorption frequency reached balance, and the layer tended towards a more rearranged or organized secondary structure upon adsorption onto the more hydrophilic surface. For the AFM force test, when a self-made EfOM-coated probe approached the membrane, a ‘jump-in’ was observed for the hydrophobic membrane after repulsion at a small distance, while only repulsive forces were observed for PVDF/SiO
2
membranes. This study demonstrated that the PVDF/SiO
2
membrane changed the entire filtration process, forming a ‘soft’ open conformation in the foulant layer.
Comparison of chemical composition in the buds of
Aralia elata
from different geographical origins of China
Authors: Qi Mingming , Hua Xiaoyu , Peng Xiaoyuan , Yan Xiufeng , Lin Jixiang
Published: August 2018

Aralia elata
buds contain many nutrients and have a pleasant taste with a unique flavour. Previous studies mainly focused on triterpene saponins in the root bark of this species, but little information existed concerning other chemical components, especially in the buds. To better understand the nutritional value of
A. elata
, we compared total flavonoids, total saponins, phenolic compounds and mineral element contents in the buds of
A. elata
collected from eight different geographical regions (S1: Benxi; S2: Linjiang; S3: Pingwu; S4: Enshi; S5: Changbaishan; S6: Shangzhi; S7: Xiaoxinganling and S8: Harbin) in China. The results showed that the basic composition in the buds presented a wide variation, with ash (8.76–10.35%), crude fibre (5.38–11.07%), polysaccharides (33.85–46.79 mg g
−1
), total flavonoid content (TFC, 4.06–48.63 mg g
−1
) and total saponins (13.62–27.85 mg g
−1
). UPLC combined with the LC-MS/MS method was used for the phenolic compounds analysis, and 11 phenolic compounds were identified and quantified in the eight samples. The total phenolic content in Enshi (S4) was significantly higher than others, and quercetin was the predominant phenolic compound in this sample. We used ICP-OES to identify and quantify nine mineral elements in the buds. The Fe and Cu contents in S5 were much higher than that of others. We obtained maximum Mg, Mn, Co and Ni contents in S4, and found rich Zn content in S7. Moreover, the maximum estimated quantities of Ca and Sr were found in S8. This study indicated that the chemical composition in the buds of
A. elata
was obviously affected by geographical origin. Our results provided an essential theoretical basis of quality evaluation of
A. elata
buds in the food production field.
Identification of 16,25-
O
-diacetyl-cucurbitane F and 25-
O
-acetyl-23,24-dihydrocucurbitacin F as novel anti-cancer chemicals
Authors: Wang Wenxue , Yang Haoran , Li Ying , Zheng Zhongfei , Liu Yongjun , Wang Haiyang , Mu Yanling , Yao Qingqiang
Published: August 2018

Seven new cucurbitane glucosides, hemslepensides J-P (
1
–
7
), and two known compounds, 16,25-
O
-diacetyl-cucurbitane F (
8
) and 25-
O
-acetyl-23,24-dihydrocucurbitacin F (
9
), were isolated from the tubers of
Hemsleya pengxianensis
var.
jinfushanensis
. The structures of
1
–
7
were elucidated using infrared absorption spectroscopy, nuclear magnetic resonance spectroscopy and high-resolution electrospray ionization mass spectrometry. The treatment of HT29 cells, human colon cancer cells, with compounds
8
and
9
inhibited cell proliferation. Further study demonstrated that compounds
8
and
9
induced F-actin aggregation, G
2
/M phase cell cycle arrest and cell apoptosis in HT29 cells. In summary, the present study enriched the chemical composition research of
H. pengxianensis
, and suggested that the compounds
8
/
9
treatment may be a potentially useful therapeutic option for colon cancer.
Mesoporous silica microparticles gated with a bulky azo derivative for the controlled release of dyes/drugs in colon
Authors: Ferri Daniel , Gaviña Pablo , Parra Margarita , Costero Ana M. , El Haskouri Jamal , Amorós Pedro , Merino Virginia , Teruel Adrián H. , Sancenón Félix , Martínez-Máñez Ramón
Published: August 2018

Mesoporous silica microparticles were prepared, loaded with the dye safranin O (
M-Saf
) or with the drug budesonide (
M-Bud
) and capped by the grafting of a bulky azo derivative. Cargo release from
M-Saf
at different pH values (mimicking those found in the gastrointestinal tract) in the absence or presence of sodium dithionite (a reducing agent mimicking azoreductase enzyme present in the colon) was tested. Negligible safranin O release was observed at pH 6.8 and 4.5, whereas a moderate delivery at pH 1.2 was noted and attributed to the hydrolysis of the urea bond that linked the azo derivative onto the external surface of the inorganic scaffold. Moreover, a marked release was observed when sodium dithionite was present and was ascribed to the rupture of the azo bond in the molecular gate. Budesonide release from
M-Bud
in the presence of sodium dithionite was also assessed by ultraviolet-visible spectroscopy and high performance liquid chromatography measurements. In addition, preliminary
in vivo
experiments with
M-Saf
carried out in mice indicated that the chemical integrity of the microparticles remained unaltered in the stomach and the small intestine, and safranin O seemed to be released in the colon.
Temperature drives Zika virus transmission: evidence from empirical and mathematical models
Authors: Tesla Blanka , Demakovsky Leah R. , Mordecai Erin A. , Ryan Sadie J. , Bonds Matthew H. , Ngonghala Calistus N. , Brindley Melinda A. , Murdock Courtney C.
Published: August 2018

Temperature is a strong driver of vector-borne disease transmission. Yet, for emerging arboviruses we lack fundamental knowledge on the relationship between transmission and temperature. Current models rely on the untested assumption that Zika virus responds similarly to dengue virus, potentially limiting our ability to accurately predict the spread of Zika. We conducted experiments to estimate the thermal performance of Zika virus (ZIKV) in field-derived
Aedes aegypti
across eight constant temperatures. We observed strong, unimodal effects of temperature on vector competence, extrinsic incubation period and mosquito survival. We used thermal responses of these traits to update an existing temperature-dependent model to infer temperature effects on ZIKV transmission. ZIKV transmission was optimized at 29°C, and had a thermal range of 22.7°C–34.7°C. Thus, as temperatures move towards the predicted thermal optimum (29°C) owing to climate change, urbanization or seasonality, Zika could expand north and into longer seasons. By contrast, areas that are near the thermal optimum were predicted to experience a decrease in overall environmental suitability. We also demonstrate that the predicted thermal minimum for Zika transmission is 5°C warmer than that of dengue, and current global estimates on the environmental suitability for Zika are greatly over-predicting its possible range.
Mosquito-borne transmission in urban landscapes: the missing link between vector abundance and human density
Authors: Romeo-Aznar Victoria , Paul Richard , Telle Olivier , Pascual Mercedes
Published: August 2018

With escalating urbanization, the environmental, demographic, and socio-economic heterogeneity of urban landscapes poses a challenge to mathematical models for the transmission of vector-borne infections. Classical coupled vector–human models typically assume that mosquito abundance is either independent from, or proportional to, human population density, implying a decreasing force of infection, orper capitainfection rate with host number. We question these assumptions by introducing an explicit dependence between host and vector densities through different recruitment functions, whose dynamical consequences we examine in a modified model formulation. Contrasting patterns in the force of infection are demonstrated, including in particular increasing trends when recruitment grows sufficiently fast with human density. Interaction of these patterns with seasonality in temperature can give rise to pronounced differences in timing, relative peak sizes, and duration of epidemics. These proposed dependencies explain empirical dengue risk patterns observed in the city of Delhi where socio-economic status has an impact on both human and mosquito densities. These observed risk trends with host density are inconsistent with current standard models. A better understanding of the connection between vector recruitment and host density is needed to address the population dynamics of mosquito-transmitted infections in urban landscapes.
Genetic determination of migration strategies in large soaring birds: evidence from hybrid eagles
Authors: Väli Ülo , Mirski Paweł , Sellis Urmas , Dagys Mindaugas , Maciorowski Grzegorz
Published: August 2018

The relative contributions of genetic and social factors in shaping the living world are a crucial question in ecology. The annual migration of birds to their wintering grounds and back provides significant knowledge in this field of research. Migratory movements are predominantly genetically determined in passerine birds, while in large soaring birds, it is presumed that social (cultural) factors play the largest role. In this study, we show that genetic factors in soaring birds are more important than previously assumed. We used global positioning system (GPS)-telemetry to compare the autumn journeys and wintering ranges of two closely related large raptorial bird species, the greater spotted eagleClanga clangaand the lesser spotted eagleClanga pomarina, and hybrids between them. The timing of migration in hybrids was similar to that of one parental species, but the wintering distributions and home range sizes were similar to those of the other. Tracking data were supported by habitat suitability modelling, based on GPS fixes and ring recoveries. These results suggest a strong genetic influence on migration strategy via a trait-dependent dominance effect, although we cannot rule out the contribution of social interactions.
Female perception of copulatory courtship by male titillators in a bushcricket
Authors: Wulff Nadja C. , Schöneich Stefan , Lehmann Gerlind U. C.
Published: August 2018

Males of the bushcricket
Metrioptera roeselii
bear paired titillators that are spiny genital structures supposedly functioning as copulatory courtship devices. During copulation, the male inserts its titillators into the female's genital chamber, where they rhythmically tap on the sensilla-covered dorsal surface of the genital fold. Here, we investigated the stimulatory function of male titillators during mating in
M. roeselii
. Tracer backfills of presumptive mechanosensory sensilla at the female genital fold revealed a thick bundle of sensory axons entering the last unfused abdominal ganglion (AG-7). Electrophysiological recordings of abdominal nerves demonstrated that females sense mechanical stimulation at their genital fold. The mechanosensory responses, however, were largely reduced by the insecticide pymetrozine that selectively blocks scolopidia of internal chordotonal organs but not campaniform and hair sensilla on the outer cuticle surface. In mating experiments, the females showed resistance behaviours towards males with asymmetrically shortened titillators, but the resistance was largely reduced when mechanoreceptors at the female's genital fold were either pharmacologically silenced by pymetrozine or mechanically blocked by capping with UV-hardened glue. Our findings support the hypothesis that the male titillators in these bushcrickets may serve as copulatory courtship devices to mechanically stimulate the female genitalia to reduce resistance behaviour.
The evolution of city life
Authors: Santangelo James S. , Rivkin L. Ruth , Johnson Marc T. J.
Published: August 2018

Urbanization represents a dominant and growing form of disturbance to Earth's natural ecosystems, affecting biodiversity and ecosystem services on a global scale. While decades of research have illuminated the effects of urban environmental change on the structure and function of ecological communities in cities, only recently have researchers begun exploring the effects of urbanization on the evolution of urban populations. The 15 articles in this special feature represent the leading edge of urban evolutionary biology and address existing gaps in our knowledge. These gaps include: (i) the absence of theoretical models examining how multiple evolutionary mechanisms interact to affect evolution in urban environments; (ii) a lack of data on how urbanization affects natural selection and local adaptation; (iii) poor understanding of whether urban areas consistently affect non-adaptive and adaptive evolution in similar ways across multiple cities; (iv) insufficient data on the genetic and especially genomic signatures of urban evolutionary change; and (v) limited understanding of the evolutionary processes underlying the origin of new human commensals. Using theory, observations from natural populations, common gardens, genomic data and cutting-edge population genomic and landscape genetic tools, the papers in this special feature address these gaps and highlight the power of urban evolutionary biology as a globally replicated ‘experiment’ that provides a powerful approach for understanding how human altered environments affect evolution.
There and back again: metagenome-assembled genomes provide new insights into two thermal pools in Kamchatka, Russia
Authors: Wilkins Laetitia G. E. , Ettinger Cassandra L. , Jospin Guillaume , Eisen Jonathan A.
Published: August 2018

Culture-independent methods have contributed substantially to our understanding of global microbial diversity. Recently developed algorithms to construct whole genomes from environmental samples have further refined, corrected and revolutionized the tree of life. Here, we assembled draft metagenome-assembled genomes (MAGs) from environmental DNA extracted from two hot springs within an active volcanic ecosystem on the Kamchatka peninsula, Russia. This hydrothermal system has been intensively studied previously with regard to geochemistry, chemoautotrophy, microbial isolation, and microbial diversity. Using a shotgun metagenomics approach, we assembled population-level genomes of bacteria and archaea from two pools using DNA that had previously been characterized via 16S rRNA gene clone libraries. We recovered 36 MAGs, 29 of medium to high quality, and placed them in the context of the current microbial tree of life. We highlight MAGs representing previously underrepresented archaeal phyla (Korarchaeota, BathyarchaeotaandAciduliprofundum) and one potentially new species within the bacterial genusSulfurihydrogenibium. Putative functions in both pools were compared and are discussed in the context of their diverging geochemistry. This study can be considered complementary to foregoing studies in the same ecosystem as it adds more comprehensive information about phylogenetic diversity and functional potential within this highly selective habitat.
The N-end Rule Pathway and Ubr1 enforce protein compartmentalization via N-terminally-encoded cellular location signals
Authors: Tran Anthony
Published: August 2018

The Arg/N-end rule pathway, a mechanism of protein degradation conserved from yeast to humans, is involved in cellular protein quality control, but its role has only been vaguely understood. Through systematic examination of single residue mutants of model misfolded substrates, and global analyses of yeast proteins, we discovered that Ubr1, an E3 ligase of the Arg/N-end rule, degrades organellar proteins that fail to reach their intended subcellular compartments. We determined that recognition by Ubr1 is dependent on location signals that are naturally embedded into the 2nd amino acid residue of the majority of proteins. The N-end rule pathway is thus likely to have been critical to the evolution of endosymbiotic relationships which paved the way for advanced eukaryotic cellular life.

Significance Statement

This work elucidates a novel role for the N-end Rule Pathway, a protein degradation pathway highly conserved from yeast to humans. We demonstrate that the N-end rule pathway enforces the cellular compartmentalization of ER and mitochondrial proteins by degrading them when they fail to successfully translocate into their intended destinations and thus become mislocalized to the cytosol. This mechanism prevents the accumulation of toxic foreign proteins within the cytosol. Recognition of the displaced proteins is dependent on cellular location signals programmed into the 2nd residue of the target proteins, as well as the tendency for the proteins to misfold in a foreign environment. These findings have significant relevance to research on the mechanisms causing human diseases involving protein misfolding.
Therapeutic effects of Hypoxia-Inducible Factor-1α (HIF-1α) on bone formation around implants in diabetic mice
Authors: Oh Sang-Min , Shin Jin-Su , Kim Il-Koo , Moon Jae-Seung , Kim Jung-Ho , Lee Sang-Kyou , Lee Jae-Hoon
Published: August 2018

Patients with uncontrolled diabetes are susceptible to implant failure due to impaired bone metabolism. Hypoxia-Inducible Factor 1α (HIF-1α), a transcription factor that is up-regulated in response to reduced oxygen condition during the bone repair process after fracture or osteotomy, is known to mediate angiogenesis and osteogenesis. However, its function is inhibited under hyperglycemic conditions in diabetic patients. The aim of this study is to evaluate the effects of exogenous HIF-1α on bone formation around implants by applying HIF-1α to diabetic mice via a novel PTD-mediated DNA delivery system. Smooth surface implants (1mm in diameter; 2mm in length) were placed in the both femurs of diabetic and normal mice. HIF-1α and placebo gels were injected to implant sites of the right and left femurs, respectively: Normal mouse with HIF-1α gel (NH), Normal mouse with placebo gel (NP), Diabetic mouse with HIF-1α gel (DH), and Diabetic mouse with placebo gel (DP). RNA sequencing was performed 4 days after surgery. Based on RNA sequencing, Differentially Expressed Genes (DEGs) were identified and HIF-1α target genes were selected. Histologic and histomorphometric results were evaluated 2 weeks after the surgery. The results showed that bone-to-implant contact (BIC) and bone volume (BV) were significantly greater in the DH group than the DP group (p < 0.05). A total of 216 genes were differentially expressed in DH group compared to DP group. On the other hand, there were 95 DEGs in the case of normal mice. Twenty-one target genes of HIF-1α were identified in diabetic mice through bioinformatic analysis of DEGs. Among the target genes, NOS2, GPNMB, CCL2, CCL5, CXCL16 and TRIM63 were manually found to be associated with wound healing-related genes. In conclusion, local administration of HIF-1α via PTD may help bone formation around the implant and induce gene expression more favorable to bone formation in diabetic mice.
Characterization of the Rosa roxbunghii Tratt transcriptome and analysis of MYB genes
Authors: Huang Xiaolong , Yan Huiqing , Zhai Lisheng , Yang Zhengting , Yi Yin
Published: August 2018

Rosa roxbunghii Tratt belongs to the Rosaceae family, and the fruit is flavorful, economic, and highly nutritious, providing health benefits. MYB proteins play key roles in R. roxbunghii’ fruit development and quality. However, the available genomic and transcriptomic information are extremely deficient. Here, a normalized cDNA library was constructed using five tissues, stem, leaf, flower, young fruit, and mature fruit, with three repetitions, and sequenced using the Illumina HiSeq 2500 platform. De novo assembly was performed, and 470.66 million clean reads were obtained. In total, 63,727 unigenes, with an average GC content of 42.08%, were determined and 59,358 were annotated. In addition, 9,354 unigenes were assigned the Gene Ontology category, and 20,202 unigenes were assigned to 25 Eukaryotic Ortholog Groups. Additionally, 19,507 unigenes were classified into 140 pathways of the Kyoto Encyclopedia of Genes and Genomes database. Using the transcriptome, 18 candidate MYB genes that were significantly expressed in mature fruit, compared with other tissues, were obtained. Among them, 10 R2R3 MYB and 1 R1 MYB were identified. The expression levels of 12 MYB genes randomly selected for qRT-PCR analysis were consistent with the RNA-seq results. A total of 37,545 microsatellites were detected, with an average EST-–SSR frequency of 0.59 (37,545/63,727). This transcriptome data will be valuable for identifying genes of interest and studying their expression and evolution.
Adaptability of mass housing: size modification of flats as a response to segregation
Authors: Huuhka Satu , Saarimaa Sini
Published: August 2018

Purpose

When dwellings fail to respond to residents’ needs, housing will suffer from segregation and buildings will possibly be demolished ahead of their time. This paper focuses on the lack of variation in the sizes of dwellings as a factor in residential segregation. It examines this issue in the context of Finnish mass housing built in the 1960s and 1970s. The purpose of the paper is to review how mass housing layouts can be adapted to produce the currently absent flat sizes.

Design/methodology/approach

The paper operates at the intersection of human geography, building stock research and adaptability research. First, statistical data are utilized to investigate how dwellings and households of different sizes are distributed over the Finnish housing stock. Second, the building layouts of mass housing are examined in detail. Third, the potential that flats in mass housing have for size modification is reviewed.

Findings

There is a disparity of available dwelling sizes between different housing types, and statistics show that the proportion of large households has decreased significantly in blocks of flats over the last decades. The lack of large dwellings in mass housing may contribute as one factor to the segregation of the neighborhoods built in the 1960s and 1970s. The findings show how the variation of apartment sizes can be increased in mass housing.

Originality/value

The housing stock is rarely examined in detail in segregation research, even though it is a major determinant for a city’s social structure. This paper argues that to address segregation sustainably, it is necessary to understand the housing stock better and to view it as an adaptable asset.
An environmental awareness purchasing intention model
Authors: Xu Lu , Prybutok Victor , Blankson Charles
Published: August 2018

Purpose

This paper posits, develops and tests the effects of general environmental awareness factors on consumers’ intentions in the Environmental Awareness Purchasing Intention Model. Environmental awareness is tested within the context of purchasing vehicles and, thus, vehicle relevant factors (perceived quality and self-image) are also included. Further, the purpose of this paper is to explain the relative contribution of general environmental awareness factors on purchasing intentions compared to quality and self-image.

Design/methodology/approach

The main thrust of the research involved a survey of 248 young automobile buyers from a large public university in Texas, USA. The data were analyzed using both multiple regression and partial least square-structural equation modeling (PLS-SEM).

Findings

Environmental attitude has a positive impact on purchasing intention, while perceived control toward environmentally responsible behavior has a negative impact. Results also show a positive impact of quality and self-image on intention to purchase environmentally friendly cars. Furthermore, the results reveal that environmental awareness factors explain less variance than perceived quality. At the same time, the results show that environmental factors, relatively, explain more variance in the decision-making process than self-image.

Originality/value

This is the first study to examine the relationship between general environmental awareness and the intention to purchase an environmentally friendly car. This study contributes to sustainable consumption literature in operations management. The paper also provides insights for developing managerial guidelines for car manufacturers based on the understanding of factors influencing environmentally friendly car purchasing intentions.
Fuzzy control-based bolt tightening for power cable maintenance robot
Authors: Jiang Wei , Zhou Zhiyuan , Yan Yu , Wu Gongping , Yu Lianqing , Li Hong Jun , Chen Wei
Published: August 2018

Purpose

In response to the poor reliability of live maintenance robots in semi-structured environments and the difficulty of monitoring their operation status, this paper aims to propose an online method for evaluating the operation status of high-voltage live maintenance robots based on fuzzy control.

Design/methodology/approach

The robot bolt tightening operation is taken as an example. During the whole operation process, the key technologies of bolt tightening are analyzed theoretically, a two-dimensional fuzzy control model of bolt tightening process control is established and the control parameters, which characterize the operation status, are obtained. Through dynamic adjustment of the fuzzy controller, real-time online monitoring of the robot operation status can be achieved.

Findings

The results of simulation experiments and 220 kV live operation experiments show that the reliability of robot bolt tightening is greatly enhanced by the proposed control method.

Originality/value

The results not only verify the engineering practicability of the fuzzy control-based method but also indicate that it can improve efficiency, safety and operability.
Dynamic frontier estimation for monitoring team performances
Authors: Yılmaz Melike , Aksezer Çağlar , Atan Tankut
Published: August 2018

Purpose

This paper aims to investigate how predictions of football league standings and efficiency measures of teams, obtained through frontier estimation technique, evolve compared to actual results.

Design/methodology/approach

The study is based on data from the Turkish first division football league. Historical data for five seasons, from 2011 to 2016, are used to compare weekly estimates to de facto results. Data envelopment analysis efficiency measures are used to estimate team performances. After each week, a data envelopment analysis is run using available data until then, and final team standings are estimated via computed efficiencies. Estimations are improved by using a data envelopment analysis model that incorporates expert knowledge about football.

Findings

Results indicate that deductions can be made about the league’s future progress. Model incorporating expert knowledge tends to estimate the performance better. Although the prediction accuracy starts out low in early stages, it improves as the season advances. Scatter of individual teams’ performances show fluxional behaviour, which attracts studying the impact of uncontrollable factors such as refereeing.

Originality/value

While all previous studies focus on season performance, this study handles the problem as a combination of weekly performance and how it converges to reality. By tracking weekly performance, managers get a chance to confront their weak performance indicators and achieve higher ranking by improving on these inefficiencies.
Changes in tissue oxygen tension, venous saturation, and Fick‐based assessments of cardiac output during hyperoxia
Authors: Perry Dorothy A. , Thomson Lindsay M. , Pigula Frank A. , Polizzotti Brian D. , DiNardo James A. , Nedder Arthur , Gauvreau Kimberlee , Kheir John N.
Published: August 2018

Background

Hyperoxemia (arterial oxygen tension >100 mm Hg) may occur in critically ill patients and have effects on mixed venous saturation (SvO2) and on Fick‐based estimates of cardiac output (CO). We investigated the effect of hyperoxemia on SvO2 and on assessments of CO using the Fick equation.

Methods

Yorkshire swine (n = 14) were anesthetized, intubated, and paralyzed for instrumentation. SvO2 (co‐oximetry) and tissue oxygen tension (tPO2, implantable electrodes) in brain and myocardium were measured during systematic manipulation of arterial oxygen tension (PaO2) using graded hyperoxia (fraction of inspired oxygen 0.21 → 0.8). Secondarily, oxygen‐ and carbon dioxide‐based estimates of CO (FickO2 and FickCO2, respectively) were compared with measurements from a flow probe placed on the aortic root.

Results

Independent of changes in measured oxygen delivery, cerebral and myocardial tPO2 increased in proportion to PaO2, as did SvO2 (P < 0.001 for all). Based on mixed model analysis, each 100 mm Hg increase in PaO2 resulted in a 4.8 ± 0.9% increase in SvO2 under the conditions tested. Because neither measured oxygen consumption, arterial oxyhemoglobin saturation or cardiac output varied significantly during hyperoxia, changes in SvO2 resulted in successively increasing errors in FickO2 during hyperoxia (34% during normoxia, 72% during FiO2 0.8). FickCO2 lacked the progressively worsening errors present in FickO2, but correlated poorly with CO.

Conclusion

SvO2 acutely changes following changes in PaO2 even absent changes in measured DO2. This may lead to errors in FickO2 estimates of CI. Further work is necessary to understand the impact of this phenomenon in disease states.
Longitudinal associations between food insecurity and substance use in a cohort of women with or at risk for HIV in the United States
Authors: Whittle Henry J. , Sheira Lila A. , Frongillo Edward A. , Palar Kartika , Cohen Jennifer , Merenstein Daniel , Wilson Tracey E. , Adedimeji Adebola , Cohen Mardge H. , Adimora Adaora A. , Ofotokun Ighovwerha , Metsch Lisa , Turan Janet M. , Wentz Eryka L. , Tien Phyllis C. , Weiser Sheri D.
Published: August 2018

Background and Aims

Few longitudinal studies have examined the relationship between food insecurity and substance use. We aimed to investigate this relationship using longitudinal data among women with or at risk for HIV in the United States.

Design

Women's Interagency HIV Study (WIHS), a prospective cohort study.

Setting

Nine sites across the United States.

Participants

A total of 2553 women with or at risk for HIV.

Measurements

Semi‐annual structured interviews were conducted during April 2013–March 2016. Food security (FS) was the primary predictor, measured using the Household Food Security Survey Module. Outcomes were: any illicit substance use except cannabis; licit or illicit cannabis use; stimulant use (crack, cocaine, or methamphetamine); opioid use (heroin or methadone in a non‐prescribed way); and prescription drug misuse (prescription narcotics, amphetamines, or tranquilizers in a non‐prescribed way) since the last visit. We used multivariable logistic regression with random effects to examine longitudinal associations of current and previous FS with the outcomes simultaneously, adjusting for socio‐demographic factors, HIV serostatus, physical health and health insurance.

Findings

Average number of visits was 4.6. At baseline, 71% of participants were HIV‐seropositive, 44% reported marginal, low, or very low FS, and 13% were using illicit substances. In adjusted analyses, current low and very low FS were significantly associated with 1.59 [95% confidence interval (CI) = 1.02, 2.46; P = 0.039] and 2.48 (95% CI = 1.52, 4.04; P < 0.001) higher odds of any illicit substance use, compared to high FS, and also with higher odds of cannabis, stimulant and opioid use, exhibiting a consistent dose–response relationship. Marginal, low, and very low FS at the previous visit were associated with 1.66 (95% CI = 1.08, 2.54; P = 0.020), 1.77 (95% CI = 1.14, 2.74; P = 0.011), and 2.28 (95% CI = 1.43, 3.64; P < 0.001) higher odds of current illicit substance use.

Conclusions

Food insecurity appears to be longitudinally associated with substance use among US women with or at risk for HIV.
What are the beliefs and perceptions of practice nurses’ influence about the uptake of the measles, mumps, and rubella vaccine?: An integrative literature review
Authors: Hill Marie Catherine , Salmon Debra , Aitken Leanne M.
Published: August 2018

Aim

The aim of this study was to ascertain the beliefs and perceptions of practice nurses’ influence about the uptake of the measles, mumps, and rubella vaccine.

Background

Immunization decision‐making for parents is a complex process. Principle health professionals involved in immunization programmes are health visitors, general practitioners, and practice nurses. There is evidence that health visitors and general practitioners influence parental immunization decision‐making. However, there is a lack of evidence about the influence of the practice nurse despite their well‐documented role in immunization.

Design

Integrative literature review.

Data sources

A systematic search of electronic databases, including CINAHL; Medline; PubMed; Google Scholar; ScienceDirect; and Scopus from February 1998 – April 2017. Hand searching and reviewing of secondary references were also undertaken.

Review methods

Two reviewers independently screened records on title and abstract. Studies where the beliefs and perceptions of practice nurses about the measles, mumps, and rubella vaccine were explored and were published in English were included. The data were analysed using the integrative review processes.

Results

Twelve studies were included; these studies were principally descriptive and were of variable methodological quality. Four themes were identified: parental immunization influencing factors, practice nurse characteristics, information and communication, and personal views and concerns. While this review provides an excellent baseline for this information, more recent research conducted in the current policy environment is urgently needed to determine if these views persist.

Conclusion

Immunization training and annual updates are essential for practice nurses to keep abreast with the evidence base underpinning national immunization programmes.
Serving style preferences for various meal arrangements among children
Authors: Nielson S. E. , Skouw S. , Olsen A.
Published: August 2018

Serving styles of meals are important for children's acceptance, but few studies have investigated how children prefer to have their meals served. The aim of this study was to investigate children's preferred serving styles of typical dinner meals in younger and older children. A total of 100 school children aged 7–8‐years and 12–14‐years old preference‐ranked six different dinner meals presented with the various food items arranged on the plate as either separated, in‐between (some mixing, some separation), or mixed serving style using pictorial stimuli. They also scored their liking of each meal on a 7‐point smiley scale. Younger girls significantly preferred a separated serving style (p ≤ .001), while no specific serving style was preferred among younger boys. Older children significantly preferred in‐between serving style (p ≤ .001) and mixed serving style (p ≤ .01) over separated serving style, but no gender differences were found between the older children.

Practical applications

As specific serving style preferences are seen in some children this knowledge could be incorporated into the preparation of daily meals for families and institutions alike. Serving meals and foods in a separated serving style could be a way of allowing the child to control the degree of possible subsequent mixing of the food items on the plate according to their individual, personal preferences. In contrast, serving a child a meal constituted by mixed food items limit the possibility of separating the elements afterward. This knowledge may optimize areas of the food industry, for example, in the context of ready‐to‐eat lunches brought to the children at school. Using serving styles with division of the food either into more rooms or by simply separating the placement of food items on the plate may allow children to adopt the serving style in accordance with their personal preferences, which may increase acceptance of the meal.
Unit Root Testing in Multiple Smooth Break Models with Nonlinear Dynamics
Authors: Sandberg Rickard
Published: August 2018

This work builds a flexible model accommodating nonlinear dynamics around a trend function with multiple (up to m) gradual shifts. Such a model is suitable for capturing the behavior of many post World War II economic time‐series subject to the onset of external causes such as oil crises, financial crises, technology changes and regulatory changes. Deriving unit root tests in this nonlinear model is of particular interest. In fact, the options of a general trend specification and nonlinear dynamics are critical to remedy unit root tests not being biased toward a non‐rejection of a unit root hypothesis and prevents the first‐differences of a series from being used too often. An asymptotic theory for the unit root tests is also established. The unit root tests are applied to G7 industrial production series, and evidence in favor of nonlinear trend ‘stationary’ models is found in a majority of the cases. The merits of the new model are further demonstrated in an estimation exercise for the US industrial production series, and evidence of four gradual shifts in the trend, different growth patterns for different periods, and business cycle asymmetries is found.