bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulated trawling: Exhaustive swimming followed by extreme crowding as contributing reasons to variable fillet quality in trawl-caught Atlantic cod (Gadus morhua)
Authors: Svalheim Ragnhild Aven , Aas-Hansen Øyvind , Heia Karsten , Karlsson-Drangsholt Anders , Olsen Stein Harris , Johnsen Helge Kreutzer 
Published: July 2018

AbstractTrawl-caught Atlantic cod (Gadus morhua) often yield highly variable fillet quality that may be related to capture stress. To investigate mechanisms involved in causing variable quality, commercial-sized (3.5±0.9 kg) Atlantic cod were swum to exhaustion in a large swim tunnel and subsequently exposed to extreme crowding (736±50 kg m-3) for 0, 1 or 3 hours in an experimental cod-end. The fish were then recuperated for 0, 3 or 6 hours in a net pen prior to slaughter to assess the possibility to reverse the reduced fillet quality. We found that exhaustive swimming and crowding were associated with increased metabolic stress, as indicated by increased plasma cortisol, blood lactate and blood haematocrit levels, accompanied by reduced quality of the fillets due to increased visual redness and lower initial muscle pH. The observed negative effects of exhaustive swimming and crowding were only to a small degree reversed within 6 hours of recuperation. The results from this study suggest that exhaustive swimming followed by extreme crowding can reduce fillet quality and contribute to the variable fillet quality seen in trawl-caught Atlantic cod. Recuperation for more than six hours may be required to reverse these effects.
Increased H-Bond Stability Relates to Altered ε-Cleavage Efficiency and Aβ Levels in the I45T Familial Alzheimer’s Disease Mutant of APP
Authors: Götz Alexander , Högel Philipp , Silber Mara , Chaitoglou Iro , Luy Burkhard , Muhle-Goll Claudia , Scharnagl Christina , Langosch Dieter 
Published: July 2018

AbstractCleavage of the amyloid precursor protein’s (APP) transmembrane domain (TMD) by γ-secretase is a crucial step in the aetiology of Alzheimer’s Disease (AD). Mutations in the APP TMD alter cleavage and lead to familial forms of AD (FAD). The majority of FAD mutations shift the preference of initial cleavage from ε49 to ε48, thus raising the AD-related Aβ42/Aβ40 ratio. The I45T mutation is among the few FAD mutations that do not alter ε-site preference, while it dramatically reduces the efficiency of ε-cleavage. Here, we investigate the impact of the I45T mutation on the backbone dynamics of the substrate TMD. Amide exchange experiments and molecular dynamics simulations in solvent and a lipid bilayer reveal an increased stability of amide hydrogen bonds at the ζ-and γ-cleavage sites. Stiffening of the H-bond network is caused by an additional H-bond between the T45 side chain and the TMD backbone, which alters dynamics within the cleavage domain. In particular, the increased H-bond stability inhibits an upward movement of the ε-sites in the I45T mutant. Thus, an altered presentation of ε-sites to the active site of γ-secretase as a consequence of restricted local flexibility provides a rationale for reduced ε-cleavage efficiency of the I45T mutant.
Subunit exchange enhances information retention by CaMKII in dendritic spines
Authors: Singh Dilawar , Bhalla Upinder Singh 
Published: July 2018

Molecular bistables are strong candidates for long-term information storage, for example, in synaptic plasticity. CaMKII is a highly expressed synaptic protein which has been proposed to form a molecular bistable switch capable of maintaining its state for years despite protein turnover and stochastic noise. It has recently been shown that CaMKII holoenzymes exchange subunits among themselves. Here we used computational methods to analyze the effect of subunit exchange on the CaMKII pathway in the presence of diffusion in two different microenvironments, the Post Synaptic Density (PSD) and spine cytosol. We show that in the PSD, subunit exchange leads to coordinated switching and prolongs state stability of the fraction of CaMKII that is present in clusters; and underlies spreading of activation among the remaining CaMKII that is uniformly distributed. Subunit exchange increases the robustness of the CaMKII switch measured as range of bistability both with respect to protein phosphatase 1 (PP1) levels and protein turnover rates. In the phosphatase-rich spine cytosol, subunit exchange leads to slower decay of activity following calcium stimuli. We find that subunit exchange can explain two time-courses of CaMKII activity decay observed in recent experiments monitoring endogenous activity of CaMKII in the spine. Overall, CaMKII exhibits multiple timescales of activity in the synapse and subunit exchange enhances the information retention ability of CaMKII by improving the stability of its switching in the PSD, and by slowing the decay of its activity in the spine cytosol. The existence of diverse timescales in the synapse has important theoretical implications for memory storage in networks.Significance StatementDespite everyday forgetfulness, we can recall some memories years after they were formed. How are we able to protect some memories for so long? Previous work has shown that the abundant brain protein Calcium/calmodulin dependent protein Kinase II (CaMKII) can form a very stable binary switch which can store information for years. Building on this work, we analyzed the implications of a recently discovered phenomenon of subunit exchange on the state switching properties of CaMKII. In subunit exchange fragments of one CaMKII molecule detatch and exchange with another. We discovered that this improves the information retention ability of CaMKII both in the context where it stores information for long times, and also where it integrates information over the timescale of minutes.
A Reconsideration of the Effect of Procyanidin on the Assembly of Collagen Type I
Authors: Wang Y. , Jin L. 
Published: July 2018

ABSTRACTIn order to elucidating the exact effect mechanism of polyphenols on the assembly of collagen, the assembled architectures of collagen treated with different amounts of procyanidin (PA) were investigated in details. The assembled morphologies of collagen were greatly influenced by the content of PA according to atomic force microcopy (AFM) images. When the content of PA was more than 20% (w/w), the fibrillar morphologies were substituted by globular aggregates, which were driven by the intense hydrogen bonding action originating from PA. While the formation of the non-fibrous aggregates was due to the coiling and entangling of flexible collagen molecules rather than their gelatinization based on the appearance of typical adsorption peaks at 222nm and 197nm on circular dichroism (CD) spectra. After being crosslinked by glutaraldehyde (GA), not only the diameters but also the lengths of fibrils increased. Unfortunately, the fibrillogenesis was still inhibited when the collagen suffered from 20% PA firstly and then 4% GA. Conversely, the fibrous morphologies of the fibrils stabilized by 4% GA and then underwent 20% PA maintained well, in spite of accompanying with grievous intertwining. This difference was derived from the change of flexibilities of collagen before and after being crosslinked by GA. Additionally, the differential scanning calorimeter (DSC) analysis confirmed the PA had no positive effect on the improvement of thermal stability of hydrous collagen, whereas the denaturation temperature of hydrated collagen stabilized by 4% GA increased from 40 °C to 80 °C.
Maternal effects influence temperature-dependent offspring survival inDrosophila melanogaster
Authors: Mohan Snigdha , Groothuis Ton G.G. , Vinke Chris , Billeter Jean-Christophe 
Published: July 2018

AbstractMothers may modulate the phenotype of their offspring by affecting their development based on her own environment. In changing environments, these maternal effects are thought to adjust offspring physiology and development and thus produce offspring better prepared to the environment experienced by the mother. However, evidence for this is scarce. Here we test the consequences of a match or mismatch between mother and offspring temperature conditions on growth, adult morphology and reproduction into the grandchildren generation in the fruit fly Drosophila melanogaster. This experimental design tests the relative contribution of maternal effects and offspring intrinsic plasticity to the phenotypic response to temperature conditions. We manipulated maternal temperature conditions by exposing mothers to either 18°C or 29°C conditions. Their eggs developed at a temperature that was either matched or mismatched with the maternal one. Survival from egg to adult was higher when the maternal and offspring environments matched, showing maternal effects affecting a trait that is a close proxy for fitness. However developmental speed, adult size and fecundity responded to temperature mostly through offspring phenotypic plasticity and maternal effects only had a small contribution. The results provide experimental evidence for maternal effects in influencing a potentially adaptive offspring response to temperature in the model organismDrosophila melanogaster.These effects appear to modulate early embryonic phenotypes such as survival, more than the adult phenotypes of the offspring.
Structural, electrochemical and mechanical studies of ultrasonic irradiation enhanced electroplating Ni coating
Authors: Ban Chaolei , Zhu Shuqin , Ma Jie , Wang Fangreng , Jia Zhengfeng , Wang Jie 
Published: July 2018

Purpose
Ni coating was electroplated on carbon steel substrate to protect carbon steel.

Design/methodology/approach
During electroplating, the ultrasonic irradiation (UI) (1 kHz) action was in situ used with different frequency. The influence of UI on the microstructure, mechanical and electrochemical performance of the coating was studied with scanning electron microscopy, X-ray diffraction, microhardness measurement, polarization curves and electrochemical impedance spectroscopy.

Findings
The results show that comparing that without UI imposition, UI during electroplating can refine the coating grain and decrease the micro-pores in the coating, resulting in improvement of the coating corrosion and hardness.

Originality/value
The imposition of UI action during electroplating Ni coating can remove intrinsic pores in the coating and compact the coating. The potential bimetallic cell between substrate and plating layer can be insulated to enhance the corrosion resistance of Ni coating. The imposition of UI action during electroplating Ni coating can refine Ni coating grain size and improve the coating haredness.
A one dimensional heat transfer model for wolverine (gulo-gulo) hair
Authors: Liu HongYan , Bahi Addie , Ko Frank K. 
Published: July 2018

Purpose
Wolverine hairs with superior heat transfer properties have been used as fur ruffs for extreme cold-weather clothing. In order to understand the exclusive mechanism of wolverine surviving in the cold areas of circumpolar, the purpose of this paper is to establish a one-dimensional fractional heat transfer equation to reveal the hidden mechanism for the hairs, and also calculate the fractal dimension of the wolverine hair using the box counting method to verify the proposed theory. The observed results (from the proposed model) found to be in good agreement with the box counting method. This model can explain the phenomenon which offers the theoretical foundation for the design of extreme cold weather clothing.

Design/methodology/approach
The authors calculated the fractal dimension of the wolverine hair using the box counting method to verify the proposed theory. The observed results (from the proposed model) found to be in good agreement with the box counting method.

Findings
The box counting method proves that the theoretical model is applicable.

Originality/value
The authors propose the first heat transfer model for the wolverine hair.
Globalization of workforce
Authors: Rivera Manuel Antonio , Murphy Kevin S. , Khalilzadeh Jalayer 
Published: July 2018

Purpose
This paper aims to investigate hospitality study abroad experiences as an educational service in which the experience encompasses services that combine tangible and intangible actions that require students to move from the classroom to a practical setting. It empirically investigates the relationship between students’ study abroad, perceived value and perceived sacrifice (monetary and non-monetary) with their overall satisfaction and internationalization intentions.

Design/methodology/approach
A total of 57 students who had completed an international externship experience were contacted and invited to complete an online survey. The online survey gauged the student’s perception of their externship experience, the overall satisfaction and the internationalization intentions. The instrument also gathered demographic information about the participants. The proposed model was estimated by using partial least squares (PLS) path modeling.

Findings
The results indicate that PLS can be used to assess the theory of consumption value for study abroad experiential learning. The results of the hypotheses testing indicate that the value students get and give is a suitable and significant predictor of satisfaction and internationalization. However, students’ satisfaction with their study abroad internship does not predict future internationalization intentions.

Originality/value
This study sheds light on hospitality students’ perceived value, satisfaction and internationalization intentions when they complete a study abroad internship program. The results indicate that the value students get and give is an appropriate and important predictor of satisfaction and attitude toward international education.
SEC 2018 examination priorities
Authors: Angstadt Janet M. , Dickstein David , Goldstein Mark , Marshall Richard 
Published: July 2018

Purpose
To analyze SEC Staff’s announced 2018 OCIE Examination priorities to provide insight to investment advisers and other regulated entities regarding areas of focus during SEC examinations.

Design/methodology/approach
This article discusses the US Securities and Exchange Commission’s (SEC) Office of Compliance Inspections and Examinations (OCIE) published its examination priorities for 2018 (the “2018 Priorities Report”).

Findings
Given that OCIE’s examination priorities for 2017 were published before the beginning of the Trump administration, differences between the 2017 and the 2018 priorities provide important insights into the focus of examinations under SEC Chair Clayton. Investment advisers and other regulated entities should allocate resources towards their preparedness for the areas of focus identified in the 2018 Priorities Report.

Originality/value
This article contains valuable insight regarding the SEC’s 2018 OCIE examination priorities and practical guidance from industry experts.
Estimating transient populations of unmarked individuals at a migratory stopover site using generalized N‐mixture models
Authors: Kwon Eunbi , Houghton Lawrence M. , Settlage Robert E. , Catlin Daniel H. , Karpanty Sarah M. , Fraser James D. 
Published: July 2018

AbstractMigration counts are popular indices used to monitor population trends over time. Advanced analytical methods for estimating abundance of unmarked, open populations now incorporate population growth models and simultaneously test for covariate effects on abundance and detection probability. However, estimating population abundance at a staging site is complicated by daily immigration and emigration of unmarked individuals.We applied a set of generalized N‐mixture models to simulated count data to test their applicability for transient populations. Using simulated datasets, parameters were unbiased when the apparent survival rate varied within a season or was mis‐specified in a model, but not when the immigration or detection probability was mis‐specified.With knowledge from the simulated data, we applied these models to daily counts of staging migratory shorebirds and estimated daily abundances accounting for variation in the detection and immigration rates. Daily counts of ruddy turnstones (Arenaria interpres) staging at Westhampton Island, New York, were collected during northward migration (1997–1999). We tested the effects of weather and tides on detection probability, and we modelled within‐season variation in immigration rates as a function of time.Covariates affecting the detection probability differed among years, but tide height consistently was correlated with detection probability. Accounting for detection and immigration rates, the predicted maximum single‐day populations of ruddy turnstones were 172%, 165% and 129% of the observed counts for each year.Synthesis and applications. Management and conservation plans for migratory species require abundance estimates that are near the true population size though they are difficult to obtain. Our study is the first empirical application of the generalized N‐mixture model that incorporates temporal trends in immigration and estimates daily abundance of a staging unmarked migratory population. Despite its inherent limitation, we suggest that the generalized N‐mixture model can estimate the abundance of transient populations with low individual heterogeneity when counts are intensively surveyed. Correct estimation of population sizes and the environmental factors affecting them can aid the conservation prioritization of species and staging sites. Moreover, the use of generalized N‐mixture models can improve our understanding of the environmental factors that shape migratory movements.
Plant species richness and functional groups have different effects on soil water content in a decade‐long grassland experiment
Authors: Fischer Christine , Leimer Sophia , Roscher Christiane , Ravenek Janneke , de Kroon Hans , Kreutziger Yvonne , Baade Jussi , Beßler Holger , Eisenhauer Nico , Weigelt Alexandra , Mommer Liesje , Lange Markus , Gleixner Gerd , Wilcke Wolfgang , Schröder Boris , Hildebrandt Anke 
Published: July 2018

Abstract

The temporal and spatial dynamics of soil water are closely interlinked with terrestrial ecosystems functioning. The interaction between plant community properties such as species composition and richness and soil water mirrors fundamental ecological processes determining above‐ground–below‐ground feedbacks. Plant–water relations and water stress have attracted considerable attention in biodiversity experiments. Yet, although soil scientific research suggests an influence of ecosystem productivity on soil hydraulic properties, temporal changes of the soil water content and soil hydraulic properties remain largely understudied in biodiversity experiments. Thus, insights on how plant diversity—productivity relationships affect soil water are lacking.

Here, we determine which factors related to plant community composition (species and functional group richness, presence of plant functional groups) and soil (organic carbon concentration) affect soil water in a long‐term grassland biodiversity experiment (The Jena Experiment).

Both plant species richness and the presence of particular functional groups affected soil water content, while functional group richness played no role. The effect of species richness changed from positive to negative and expanded to deeper soil with time. Shortly after establishment, increased topsoil water content was related to higher leaf area index in species‐rich plots, which enhanced shading. In later years, higher species richness increased topsoil organic carbon, likely improving soil aggregation. Improved aggregation, in turn, dried topsoils in species‐rich plots due to faster drainage of rainwater. Functional groups affected soil water distribution, likely due to plant traits affecting root water uptake depths, shading, or water‐use efficiency. For instance, topsoils in plots containing grasses were generally drier, while plots with legumes were moister.

Synthesis. Our decade‐long experiment reveals that the maturation of grasslands changes the effects of plant richness from influencing soil water content through shading effects to altering soil physical characteristics in addition to modification of water uptake depth. Functional groups affected the soil water distribution by characteristic shifts of root water uptake depth, but did not enhance exploitation of the overall soil water storage. Our results reconcile previous seemingly contradictory results on the relation between grassland species diversity and soil moisture and highlight the role of vegetation composition for soil processes.
Evaluation of mitochondrial respiratory function in rat cardiomyocytes under different glucose conditions, using an extracellular flux analysis method
Authors: Tsubone Hirokazu , Mutoh Tatsushi 
Published: July 2018

SummaryWe studied the effect of glucose supply on mitochondrial respiratory function (MRF) of neonatal rat cardiomyocytes, using a novel extracellular flux analysis. Fundamental respiratory parameters regarding oxygen consumption rate in mitochondria showed glucose concentration‐dependent changes, where a significant increase or decrease in these parameters was observed to be associated with glucose concentrations ranging between 10% and 1000% of the concentration used in standard medium (3151 mg/L), respectively. By contrast, the extracellular acidification rate, a parameter of anaerobic activity, was shown to decrease under low‐glucose conditions, whereas it increased after inhibiting complex V (ATP synthase) under the same glucose conditions. These findings provide a beneficial basis for various experimental studies on mitochondrial metabolism in cardiomyocytes.
Attachment between heterotrophic bacteria and microalgae influences symbiotic microscale interactions
Authors: Samo Ty J. , Kimbrel Jeffrey A. , Nilson Daniel J. , Pett‐Ridge Jennifer , Weber Peter K. , Mayali Xavier 
Published: July 2018

SummaryThe surface and surroundings of microalgal cells (phycosphere) are critical interaction zones but have been difficult to functionally interrogate due to methodological limitations. We examined effects of phycosphere‐associated bacteria for two biofuel‐relevant microalgal species (Phaeodactylum tricornutum and Nannochloropsis salina) using stable isotope tracing and high spatial resolution mass spectrometry imaging (NanoSIMS) to quantify elemental exchanges at the single‐cell level. Each algal species responded differently to bacterial attachment. In P. tricornutum, a high percentage of cells had attached bacteria (92%–98%, up to eight bacteria per alga) and fixed 64% more carbon with attached bacteria compared to axenic cells. In contrast, N. salina cells were less commonly associated with bacteria (42%–63%), harboured fewer bacteria per alga, and fixed 10% more carbon without attached bacteria compared to axenic cells. An uncultivated bacterium related to Haliscomenobacter sp. was identified as an effective mutualist; it increased carbon fixation when attached to P. tricornutum and incorporated 71% more algal‐fixed carbon relative to other bacteria. Our results illustrate how phylogenetic identity and physical location of bacteria and algae facilitate diverse metabolic responses. Phycosphere‐mediated, mutualistic chemical exchanges between autotrophs and heterotrophs may be a fruitful means to increase microalgal productivity for applied engineering efforts.