bluuebunny/crossref_metadata_2025 huggingface dataset:
Data gaps in anthropogenically driven local‐scale species richness change studies across the Earth's terrestrial biomes
Authors: Murphy Grace E. P. , Romanuk Tamara N.
Published: March 2016

There have been numerous attempts to synthesize the results of local‐scale biodiversity change studies, yet several geographic data gaps exist. These data gaps have hindered ecologist's ability to make strong conclusions about how local‐scale species richness is changing around the globe. Research on four of the major drivers of global change is unevenly distributed across the Earth's biomes. Here, we use a dataset of 638 anthropogenically driven species richness change studies to identify where data gaps exist across the Earth's terrestrial biomes based on land area, future change in drivers, and the impact of drivers on biodiversity, and make recommendations for where future studies should focus their efforts. Across all drivers of change, the temperate broadleaf and mixed forests and the tropical moist broadleaf forests are the best studied. The biome–driver combinations we have identified as most critical in terms of where local‐scale species richness change studies are lacking include the following: land‐use change studies in tropical and temperate coniferous forests, species invasion and nutrient addition studies in the boreal forest, and warming studies in the boreal forest and tropics. Gaining more information on the local‐scale effects of the specific human drivers of change in these biomes will allow for better predictions of how human activity impacts species richness around the globe.
Optimal hurricane overwash thickness for maximizing marsh resilience to sea level rise
Authors: Walters David C. , Kirwan Matthew L.
Published: March 2016

The interplay between storms and sea level rise, and between ecology and sediment transport governs the behavior of rapidly evolving coastal ecosystems such as marshes and barrier islands. Sediment deposition during hurricanes is thought to increase the resilience of salt marshes to sea level rise by increasing soil elevation and vegetation productivity. We use mesocosms to simulate burial of Spartina alterniflora during hurricane‐induced overwash events of various thickness (0–60 cm), and find that adventitious root growth within the overwash sediment layer increases total biomass by up to 120%. In contrast to most previous work illustrating a simple positive relationship between burial depth and vegetation productivity, our work reveals an optimum burial depth (5–10 cm) beyond which burial leads to plant mortality. The optimum burial depth increases with flooding frequency, indicating that storm deposition ameliorates flooding stress, and that its impact on productivity will become more important under accelerated sea level rise. Our results suggest that frequent, low magnitude storm events associated with naturally migrating islands may increase the resilience of marshes to sea level rise, and in turn, slow island migration rates. Synthesis: We find that burial deeper than the optimum results in reduced growth or mortality of marsh vegetation, which suggests that future increases in overwash thickness associated with more intense storms and artificial heightening of dunes could lead to less resilient marshes.
Classification based hypothesis testing in neuroscience: Below‐chance level classification rates and overlooked statistical properties of linear parametric classifiers
Authors: Jamalabadi Hamidreza , Alizadeh Sarah , Schönauer Monika , Leibold Christian , Gais Steffen
Published: March 2016

Multivariate pattern analysis (MVPA) has recently become a popular tool for data analysis. Often, classification accuracy as quantified by correct classification rate (CCR) is used to illustrate the size of the effect under investigation. However, we show that in low sample size (LSS), low effect size (LES) data, which is typical in neuroscience, the distribution of CCRs from cross‐validation of linear MVPA is asymmetric and can show classification rates considerably below what would be expected from chance classification. Conversely, the mode of the distribution in these cases is above expected chance levels, leading to a spuriously high number of above chance CCRs. This unexpected distribution has strong implications when using MVPA for hypothesis testing. Our analyses warrant the conclusion that CCRs do not well reflect the size of the effect under investigation. Moreover, the skewness of the null‐distribution precludes the use of many standard parametric tests to assess significance of CCRs. We propose that MVPA results should be reported in terms of P values, which are estimated using randomization tests. Also, our results show that cross‐validation procedures using a low number of folds, e.g. twofold, are generally more sensitive, even though the average CCRs are often considerably lower than those obtained using a higher number of folds. Hum Brain Mapp 37:1842–1855, 2016. © 2016 Wiley Periodicals, Inc.
MicroRNA‐122 regulates polyploidization in the murine liver
Authors: Hsu Shu‐hao , Delgado Evan R. , Otero P. Anthony , Teng Kun‐yu , Kutay Huban , Meehan Kolin M. , Moroney Justin B. , Monga Jappmann K. , Hand Nicholas J. , Friedman Joshua R. , Ghoshal Kalpana , Duncan Andrew W.
Published: March 2016

A defining feature of the mammalian liver is polyploidy, a numerical change in the entire complement of chromosomes. The first step of polyploidization involves cell division with failed cytokinesis. Although polyploidy is common, affecting ∼90% of hepatocytes in mice and 50% in humans, the specialized role played by polyploid cells in liver homeostasis and disease remains poorly understood. The goal of this study was to identify novel signals that regulate polyploidization, and we focused on microRNAs (miRNAs). First, to test whether miRNAs could regulate hepatic polyploidy, we examined livers from Dicer1 liver‐specific knockout mice, which are devoid of mature miRNAs. Loss of miRNAs resulted in a 3‐fold reduction in binucleate hepatocytes, indicating that miRNAs regulate polyploidization. Second, we surveyed age‐dependent expression of miRNAs in wild‐type mice and identified a subset of miRNAs, including miR‐122, that is differentially expressed at 2‐3 weeks, a period when extensive polyploidization occurs. Next, we examined Mir122 knockout mice and observed profound, lifelong depletion of polyploid hepatocytes, proving that miR‐122 is required for complete hepatic polyploidization. Moreover, the polyploidy defect in Mir122 knockout mice was ameliorated by adenovirus‐mediated overexpression of miR‐122, underscoring the critical role miR‐122 plays in polyploidization. Finally, we identified direct targets of miR‐122 (Cux1, Rhoa, Iqgap1, Mapre1, Nedd4l, and Slc25a34) that regulate cytokinesis. Inhibition of each target induced cytokinesis failure and promoted hepatic binucleation. Conclusion: Among the different signals that have been associated with hepatic polyploidy, miR‐122 is the first liver‐specific signal identified; our data demonstrate that miR‐122 is both necessary and sufficient in liver polyploidization, and these studies will serve as the foundation for future work investigating miR‐122 in liver maturation, homeostasis, and disease. (Hepatology 2016;64:599‐615)
The June 2013 Alberta catastrophic flooding event – part 2: fine‐scale precipitation and associated features
Authors: Kochtubajda B. , Stewart R. E. , Boodoo S. , Thériault J. M. , Li Y. , Liu A. , Mooney C. , Goodson R. , Szeto K.
Published: March 2016

Data obtained from a variety of sources including the Canadian Lightning Detection Network, weather radars, weather stations and operational numerical weather model analyses were used to address the evolution of precipitation during the June 2013 southern Alberta flood. The event was linked to a mid‐level closed low pressure system to the west of the region and a surface low pressure region initially to its south. This configuration brought warm, moist unstable air into the region that led to dramatic, organized convection with an abundance of lightning and some hail. Such conditions occurred in the southern parts of the region whereas the northern parts were devoid of lightning. Initially, precipitation rates were high (extreme 15‐min rainfall rates up to 102 mm h−1 were measured) but decreased to lower values as the precipitation shifted to long‐lived stratiform conditions. Both the convective and stratiform precipitation components were affected by the topography. Similar flooding events, such as June 2002, have occurred over this region although the 2002 event was colder and precipitation was not associated with substantial convection over southwest Alberta. Copyright © 2016 Her Majesty the Queen in Right of Canada. Hydrological Processes. © John Wiley & Sons, Ltd.
Rotenone induces apoptosis in human lung cancer cells by regulating autophagic flux
Authors: Hu Wensi , Tian Hui , Yue Weiming , Li Lin , Li Shuhai , Gao Cun , Si Libo , Qi Lei , Lu Ming , Hao Bin , Shan Shuyu
Published: March 2016

Reactive oxygen species (ROS) are at the center of many physiological and pathological processes. ROS generated due to oxidative stress can potentiate both cancer initiation and progression. Rotenone, which is an inhibitor of the mitochondrial electron transport chain complex I, results in the activation of NOX2 and release of ROS, and has been shown to display anticancer activity through the induction of apoptosis in various cancer cells. The mechanistic link between rotenone‐dependent activation of NOX2 and induction of apoptosis is still elusive. In this study, we used the human lung cancer A549 cells to study the molecular mechanism(s) involved between rotenone‐dependent activation of NOX2 and impairment of autophagic machinery. We report that acute exposure to rotenone induced mild NOX2‐dependnet oxidative stress, which impaired the autophagic flux, resulting in cytosolic accumulation of LC3 and p62/STSQM1. We further show that this induction occurs through the PI3K/Akt/mTORC1 signaling pathway. We furthermore show that chronic exposure to rotenone lead to excessive NOX2‐dependent ROS generation, increases autophagy, and decreases p62 level via increased‐autophagic flux. Taken together, this study is the first mechanistic elucidation of how rotenone can be used to potently target cancer cells without overhauling the entire cellular machinery. © 2016 IUBMB Life 68(5):388–393, 2016
MicroRNA‐199b expression level and coliform count in irritable bowel syndrome
Authors: Mansour Marwa A. , Sabbah Norhan A. , Mansour Shymaa A. , Ibrahim Amany M.
Published: March 2016

Irritable bowel syndrome (IBS) is a common intestinal disorder. The pathophysiology of IBS may involve an altered intestinal microbiota. Recent studies have shown that alterations in microRNA (miRNA) levels have affected IBS and its subtypes. We aimed to compare both the count of Coliform and serum level of miRNA‐199b between patients with IBS and healthy controls and to find the relationship between the Coliform and miRNAs in patients with IBS. Patients with IBS were classified into three subgroups based on their predominant bowel pattern as defined by Rome III criteria. Quantitative culture of Coliform and determination of serum miRNA‐199b expression level by quantitative real‐time PCR in IBS group versus healthy controls were performed. There was a significant increase in the count of Coliform in patients with IBS and its different subtypes when compared with healthy controls. There was a significant decrease of serum miR‐199b expression level in patients with IBS and its different subtypes when compared with healthy controls with the highest level (1.9 ± 0.53 log scale) in healthy controls and lowest one (0.71 ± 0.27 log scale) in IBS with diarrhea (IBS‐D) subtype. Moreover, there was a negative correlation between the count of Coliform and the serum miRNA‐199b expression level in IBS. This study reported that there was a significant increase in the count of Coliform and a decrease in the serum miRNA‐199b expression level. In addition, there was a negative correlation between them in patients with IBS and its different subtypes when compared with healthy controls. © 2016 IUBMB Life, 68(5):335–342, 2016
Bioelectrochemical hydrogen production with cheese whey as sole substrate
Authors: Rago Laura , Baeza Juan A , Guisasola Albert
Published: March 2016

BACKGROUND

Microbial electrochemical systems (MXCs) are an emerging technology aiming at recovering energy contained in wastewaters either as electrical energy in microbial fuel cells (MFCs) or as hydrogen in microbial electrolysis cells (MECs). Successful results have been reported with readily biodegradable substrates, but the performance with real complex substrates needs to be evaluated to bridge the gap between lab‐ and full‐scale. This work aims at studying bioelectrochemical hydrogen production using real cheese whey as sole substrate.

RESULTS

A microbial consortium able to consume cheese whey to produce electricity or H2 was developed. Cheese whey was fermented mainly by lactic acid bacteria (Enterococcus genus) and exoelectrogenic activity was performed by Geobacter sp. The coulombic efficiency was 49 ± 8% in the MFC fed only with cheese whey, which is higher than most previous values reported for MFCs fed with dairy products. Good results for H2 production in MEC (0.8 LH2 L−1REACTOR d−1) were also obtained.

CONCLUSION

The high potentiality of cheese whey as carbon source for bioelectrochemical systems is demonstrated in this study. The populations involved were determined by advanced microbial tools. The efficient selection of a syntrophic consortium to produce H2 directly from cheese whey in a single‐chamber MEC was demonstrated. © 2016 Society of Chemical Industry
Quantitative evaluation of left ventricular volume and function in middle‐aged healthy chinese people with 3 Tesla MRI
Authors: Li Cai‐Ying , Gao Bu‐Lang , Guo Fu‐Qian , Zhang Xue‐Jing , Fan Qiong‐Ying , Wu Bai‐Lin , Xiang Cheng , Liu Xiao‐Wei , Pan Tong
Published: March 2016

Purpose

To quantitatively investigate left ventricular volume and function in middle‐aged healthy subjects.

Materials and Methods

Ninety healthy volunteers underwent cardiac 3 Tesla MRI. The left ventricular end‐diastolic volume (EDV) and end‐systolic volume (ESV), stroke volume (SV), ejection fraction (EF), cardiac output (CO), myocardial mass (MM), and their normalized indices (EDVI, ESVI, SVI, CI, and MI, respectively) after corrected with the body surface area (BSA) were analyzed and compared at different ages.

Results

All subjects had successfully completed the 3‐Tesla cardiac MR. Females had significantly smaller EDV (110.5 ± 9.2 versus 125.7 ± 8.3 mL), ESV (36.1 ± 3.5 versus 41.5 ± 3.8 mL), SV (74.3 ± 6.3 versus 84.2 ± 6.7 mL), CO (5.4 ± 0.8 versus 5.8 ± 0.9 l/min) and MM (73.0 ± 10.5 versus 94.8 ± 10.6 g) than males (P < 0.05). The EF had no significant (P = 0.47) difference between genders (67.3 ± 1.7 percent in females versus 66.9 ± 2.4 percent in males). After normalization with BSA, no significant (P > 0.05) difference was detected between the genders in EDVI (71.2 ± 4.3 versus 71.1 ± 4.2 mL/m2, P = 0.882), ESVI (23.3 ± 1.9 versus 23.5 ± 1.9 mL/m2, P = 0.733) and SVI (47.9 ± 2.9 versus 47.7 ± 3.7 mL/m2, P = 0.698) except for CI and MI. Females had significantly (P < 0.05) greater CI (3.5 ± 0.4 versus 3.3 ± 0.4) but smaller MI (46.9 ± 5.3 versus 53.6 ± 7.6) than males. EDV, EDVI, ESV, ESVI, SV, and SVI significantly (P < 0.05) decreased with age increase. BSA was positively correlated with EDV, ESV, SV, MM, and CO. No significance (P > 0.05) was detected in other parameters.

Conclusion

The left ventricular volume and function differs in women compared with men in the middle‐aged population, and these parameters have a tendency of decrease with ageing. J. Magn. Reson. Imaging 2016;44:1143–1150.
Evaluation of cisterna chyli diameter with MRI in patients with chronic kidney disease
Authors: Albayrak Eda , Ozmen Zafer , Sahin Safak , Demir Osman , Erken Ertugrul
Published: March 2016

Purpose

To evaluate cisterna chyli (CC) diameter with magnetic resonance imaging (MRI) in patients with chronic kidney disease (CKD).

Materials and Methods

The study included 71 patients with CKD and 68 healthy controls. In both groups, the largest transverse diameter of CC was measured in axial heavily T2‐weighted images using a 1.5T MRI. The diameter of the CC in the CKD patients and control group were compared, and the correlations between the CKD, glomerular filtration rate (GFR), and stage of CKD were investigated. The CC diameters were compared between/among groups with independent sample t‐test or one‐way analysis of variance (ANOVA). A receiver operating characteristic (ROC) curve was constructed for CC diameter to determine the effectiveness of various cutoff points for the presence of CKD. The Pearson correlation coefficient was used to examine correlation between CC diameter and GFR. Multivariate logistic regression models were implemented in order to examine to determine relation among selected variables and study group.

Results

The average CC diameter was 5.68 ± 2.55 mm in the CKD group, and 3.18 ± 2.24 mm in control group (P < 0.001). The CC diameter showed an increase with more severe stages of the disease (P < 0.001). There was a significant negative correlation between CC diameter and GFR (r –0.447, P < 0.001). Based on multivariate analysis, it was determined that the only factor associated with severity of disease was CC diameter (odds ratio: 1.636, 95% confidence interval: 1.314–2.037, P < 0.0001). Based on ROC analysis, the optimal CC diameter cutoff value for detecting CKD was 4.5 mm, with sensitivity and specificity values of 0.704 and 0.824, respectively.

Conclusion

CC diameter is observed to be larger in patients with CKD than in the normal population. Additionally, CC diameter increased with more severe stages of CKD. According to our results, CC diameter might be used as an MRI marker to indicate the presence and severity of CKD. J. MAGN. RESON. IMAGING 2016;44:890–896.
Parameter optimization for reproducible cardiac 1H‐MR spectroscopy at 3 Tesla
Authors: de Heer Paul , Bizino Maurice B. , Lamb Hildo J. , Webb Andrew G.
Published: March 2016

Purpose

To optimize data acquisition parameters in cardiac proton MR spectroscopy, and to evaluate the intra‐ and intersession variability in myocardial triglyceride content.

Materials and Methods

Data acquisition parameters at 3 Tesla (T) were optimized and reproducibility measured using, in total, 49 healthy subjects. The signal‐to‐noise‐ratio (SNR) and the variance in metabolite amplitude between averages were measured for: (i) global versus local power optimization; (ii) static magnetic field (B0) shimming performed during free‐breathing or within breathholds; (iii) post R‐wave peak measurement times between 50 and 900 ms; (iv) without respiratory compensation, with breathholds and with navigator triggering; and (v) frequency selective excitation, Chemical Shift Selective (CHESS) and Multiply Optimized Insensitive Suppression Train (MOIST) water suppression techniques. Using the optimized parameters intra‐ and intersession myocardial triglyceride content reproducibility was measured. Two cardiac proton spectra were acquired with the same parameters and compared (intrasession reproducibility) after which the subject was removed from the scanner and placed back in the scanner and a third spectrum was acquired which was compared with the first measurement (intersession reproducibility).

Results

Local power optimization increased SNR on average by 22% compared with global power optimization (P = 0.0002). The average linewidth was not significantly different for pencil beam B0 shimming using free‐breathing or breathholds (19.1 Hz versus 17.5 Hz; P = 0.15). The highest signal stability occurred at a cardiac trigger delay around 240 ms. The mean amplitude variation was significantly lower for breathholds versus free‐breathing (P = 0.03) and for navigator triggering versus free‐breathing (P = 0.03) as well as for navigator triggering versus breathhold (P = 0.02). The mean residual water signal using CHESS (1.1%, P = 0.01) or MOIST (0.7%, P = 0.01) water suppression was significantly lower than using frequency selective excitation water suppression (7.0%). Using the optimized parameters an intrasession limits of agreement of the myocardial triglyceride content of ‐0.11% to +0.04%, and an intersession of ‐0.15% to +0.9%, were achieved. The coefficient of variation was 5% for the intrasession reproducibility and 6.5% for the intersession reproducibility.

Conclusion

Using approaches designed to optimize SNR and minimize the variation in inter‐average signal intensities and frequencies/phases, a protocol was developed to perform cardiac MR spectroscopy on a clinical 3T system with high reproducibility. J. Magn. Reson. Imaging 2016;44:1151–1158.
Impact of trophic state on the distribution of intact polar lipids in surface waters of lakes
Authors: Bale Nicole J. , Hopmans Ellen C. , Schoon Petra L. , de Kluijver Anna , Downing John A. , Middelburg Jack J. , Sinninghe Damsté Jaap S. , Schouten Stefan
Published: March 2016

We characterized the intact polar lipid (IPL) composition in the surface waters of 22 lakes from Minnesota and Iowa, ranging in trophic state between eutrophic and oligo‐mesotrophic, to investigate the impact of trophic state on IPL composition. A high diversity of IPL classes was detected. Most IPL classes were detected in all lakes, but the eutrophic lakes contained a significantly higher relative abundance of lyso‐phosphatidylcholine (PC) than the oligo‐mesotrophic lakes, which in turn were characterized by significantly higher relative abundance of hydroxymethyltrimethyl‐alanine/trimethyl‐homoserine (DGTA/DGTS) betaines, ornithine lipids and the recently discovered trimethyl ornithine (TMO) lipids. The higher relative abundance of ornithines and TMOs may relate to a higher contribution of heterotrophic bacteria relative to phytoplankton while the higher abundance of the DGTA/DGTS betaines may relate to substitution by microorganisms of these non‐P lipids for PC under P‐stress, as has been observed in other environments. We also detected a variety of heterocyst glycolipids (HGs) derived from N2‐fixing heterocystous Cyanobacteria in all lakes, suggesting the presence of these Cyanobacteria in the full range of trophic conditions. Correlation of HG abundance with environmental data showed that high productivity lakes have high HG abundances, while other distributional differences in HGs, which did not correlate with environmental parameters, are likely due to differences in species composition. We conclude that the significant differences in IPL composition between the eutrophic and oligo‐mesotrophic lakes are either due to adaptation of the membrane composition to nutrient conditions or due to general divergences in microbial composition under the different conditions.
Carotenoid accumulation in copepods is related to lipid metabolism and reproduction rather than to UV‐protection
Authors: Schneider Tobias , Grosbois Guillaume , Vincent Warwick F. , Rautio Milla
Published: March 2016

Accumulation of carotenoid pigments in copepods has often been described as a plastic adaptation providing photoprotection against ultraviolet radiation (UVR). However, reports of seasonal carotenoid maxima in winter, when UVR is low, challenge the proposed driving role of UVR. Therefore, we here evaluate the mechanistic connection between UVR and the seasonal pattern of copepod carotenoid pigmentation. We assessed the carotenoids, fatty acid content and reproduction of Leptodiaptomus minutus along with UVR exposure, water temperature, phytoplankton pigments, and fish predation in a boreal lake during 18 months covering two winter seasons. The predominant carotenoid astaxanthin occurred in free form as well as esterified with fatty acids. Mono‐ and diesters accounted for 62–93% of total astaxanthin and varied seasonally in close correlation with fatty acids. The seasonal variability in total astaxanthin content of the copepods was characterized by net accumulation in late fall of up to 0.034 μg (mg dry mass)−1 d−1, which led to the mid‐winter maximum of 3.89 ± 0.31 μg mg−1. The two periods of net loss (−0.018 μg mg−1 d−1 and −0.021 μg mg−1 d−1) coincided with peaks of egg production in spring and summer leading to minimum astaxanthin content (0.86 ± 0.03 μg mg−1) in fall. This period was also characterized by the highest predation pressure by young‐of‐the‐year fish. The results suggest that accumulation of astaxanthin in copepods is strongly related to lipid metabolism but not to UVR‐photoprotection, and that seasonal changes of fatty acids and carotenoids are related to the reproduction cycle.
Carbon isotope fractionation in phytoplankton as a potential proxy for pH rather than for [CO2(aq)]: Observations from a carbonate lake
Authors: Wang Shilu , Yeager Kevin M. , Lu Weiqi
Published: March 2016

The method of reconstructing paleoatmospheric CO2 levels using carbon isotope signatures of organic matter buried in sediments has been questioned due to the dubious foundation that carbon isotope fractionation during phytoplankton photosynthesis (εp) is controlled primarily by aquatic CO2 concentration ([CO2(aq)]). Consequently, what carbon isotope data from bulk sedimentary organic matter reflects is a puzzle. In this study, we determined the carbon isotope compositions of dissolved inorganic carbon and particulate organic carbon in a lake located in a carbonate area. Partial correlation analysis was employed to distinguish between direct and indirect factors in controlling εp. The results show that εp is more closely, and more steadily related with pH than with [CO2(aq)], which is in accordance with recent advances in our understanding of the physiology of carbon utilization by phytoplankton for CO2 and
. Therefore, we propose that carbon isotope fractionation in phytoplankton is more suitable as a proxy of pH than of [CO2(aq)]. One advantage of this amendment is that information on
, the main species of carbon uptake by phytoplankton, is likewise included. In the future, culture experiments aiming at revealing the relationship between pH and cellular carbon isotope signatures is necessary to construct a new isotope fractionation formula to couple the different effects of CO2 and
, which is of critical importance to improve the understanding of carbon isotope fractionation, and to more precisely model pH and CO2.
Reply to comment: Prey perception in feeding‐current feeding copepods
Authors: Kiørboe Thomas , Gonçalves Rodrigo J. , Couespel Damien , van Someren Gréve Hans , Saiz Enric , Tiselius Peter
Published: March 2016

We reply to the comments of Paffenhöfer and Jiang () who argues that remote chemical prey perception is necessary for feeding‐current feeding copepods to fulfill their nutritional requirements in a dilute ocean, that remote chemical prey detection may only be observed at very low prey concentrations, and that chemical prey perception is feasible if prey cells release dissolved organic material in short‐lasting but intense bursts. We demonstrate that mechanoreception at a very short range is sufficient to sustain a living, even in a dilute ocean. Further, if chemoreception requires that prey cells have short intense leakage burst, only a very small fraction of prey cells would be available to the copepod at any instance in time and, thus would be inefficient at low prey concentration. Finally, we report a few new observations of prey capture in two species of copepods, Temora longicornis and Centropages hamatus, offered a 45‐μm sized dinoflagellate at very low concentration. The observed short prey detection distances, up to a few prey cell radii, are consistent with mechanoreception and we argue briefly that near‐field mechanoreception is the most likely and common prey perception mechanism in calanoid copepods.
Comment: On phytoplankton perception by calanoid copepods
Authors: Paffenhöfer Gustav‐Adolf , Jiang Houshuo
Published: March 2016

Three publications recently reported that calanoid copepods, feeding on phytoplankton cells by using a feeding current, perceived such cells by mechanoperception. There was no evidence of remote chemically‐mediated perception of those cells. These observations differ from earlier findings that feeding‐current producing calanoids are able to detect phytoplankton cells by chemoperception at a distance from their particle‐collecting setae of their cephalic appendages. The results on mechanoperception and the earlier published data on chemoperception will be presented and discussed. In addition, the concentration of chemicals within the phycosphere of food cells will be re‐examined. We conclude that chemoperception of phytoplankton cells by calanoid copepods in a feeding current is feasible.
Accelerated phase contrast flow imaging with direct complex difference reconstruction
Authors: Sun Aiqi , Zhao Bo , Ma Ke , Zhou Zechen , He Le , Li Rui , Yuan Chun
Published: March 2016

Purpose

To propose and evaluate a new model‐based reconstruction method for highly accelerated phase‐contrast magnetic resonance imaging (PC‐MRI) with sparse sampling.

Theory and Methods

This work presents a new constrained reconstruction method based on low‐rank and sparsity constraints to accelerate PC‐MRI. More specifically, we formulate the image reconstruction problem into separate reconstructions of flow‐reference image sequence and complex differences. We then utilize the joint partial separability and sparsity constraints to enable high quality reconstruction from highly undersampled
‐space data. We further integrate the proposed method with ESPIRiT based parallel imaging model to effectively handle multichannel acquisition.

Results

The proposed method was evaluated with in vivo data acquired from both 2D and 3D PC flow imaging experiments, and compared with several state‐of‐the‐art methods. Experimental results demonstrate that the proposed method leads to more accurate velocity reconstruction from highly undersampled
‐space data, and particularly superior capability of capturing the peak velocity of blood flow. In terms of flow visualization, blood flow patterns obtained from the proposed reconstruction also exhibit better agreement with those obtained from the fully sampled reference.

Conclusion

The proposed method achieves improved accuracy over several state‐of‐the‐art methods for velocity reconstruction with highly accelerated
‐space data. Magn Reson Med 77:1036–1048, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Sequential combination of k‐t principle component analysis (PCA) and partial parallel imaging: k‐t PCA GROWL
Authors: Qi Haikun , Huang Feng , Zhou Hongmei , Chen Huijun
Published: March 2016

Purpose

k‐t principle component analysis (k‐t PCA) is a distinguished method for high spatiotemporal resolution dynamic MRI. To further improve the accuracy of k‐t PCA, a combination with partial parallel imaging (PPI), k‐t PCA/SENSE, has been tested. However, k‐t PCA/SENSE suffers from long reconstruction time and limited improvement. This study aims to improve the combination of k‐t PCA and PPI on both reconstruction speed and accuracy.

Methods

A sequential combination scheme called k‐t PCA GROWL (GRAPPA operator for wider readout line) was proposed. The GRAPPA operator was performed before k‐t PCA to extend each readout line into a wider band, which improved the condition of the encoding matrix in the following k‐t PCA reconstruction. k‐t PCA GROWL was tested and compared with k‐t PCA and k‐t PCA/SENSE on cardiac imaging.

Results

k‐t PCA GROWL consistently resulted in better image quality compared with k‐t PCA/SENSE at high acceleration factors for both retrospectively and prospectively undersampled cardiac imaging, with a much lower computation cost. The improvement in image quality became greater with the increase of acceleration factor.

Conclusion

By sequentially combining the GRAPPA operator and k‐t PCA, the proposed k‐t PCA GROWL method outperformed k‐t PCA/SENSE in both reconstruction speed and accuracy, suggesting that k‐t PCA GROWL is a better combination scheme than k‐t PCA/SENSE. Magn Reson Med 77:1058–1067, 2017. © 2016 International Society for Magnetic Resonance in Medicine
Growth hormone receptor expression in human gluteal versus abdominal subcutaneous adipose tissue: Association with body shape
Authors: Karastergiou Kalypso , Bredella Miriam A. , Lee Mi‐Jeong , Smith Steven R. , Fried Susan K. , Miller Karen K.
Published: March 2016

Objective

Growth hormone (GH) administration reduces abdominal, but not lower body, fat mass. To gain insight into the underlying mechanisms, this study examined the expression of the GH receptor (GHR) and some of its targets in abdominal and gluteal adipose tissue.

Methods

GHR and GH targets in the lipolytic pathway were assessed (quantitative PCR/Western blotting) in adipose aspirates from premenopausal women [n = 15, age 26.9 ± 6.1 years, body mass index (BMI) 28.0 ± 6.8 kg/m2] and men (n = 28, age 29.2 ± 7.0 years, BMI 26.9 ± 3.7 kg/m2).

Results

GHR mRNA expression was lower in the gluteal depot when compared with the abdominal depot (P = 0.01). Abdominal GHR correlated negatively with age and BMI, whereas gluteal GHR was associated with lower waist‐to‐hip ratio (WHR), that is, pear shape. In both sites, GHR mRNA correlated strongly with genes important for the regulation of lipolysis: adipose tissue triglyceride lipase (ATGL), hormone‐sensitive lipase, perilipin, and CIDEA (all P < 0.001), independently of BMI, WHR, age, and sex. GHR protein was lower in the gluteal fat when compared with the abdominal fat (P = 0.03) and correlated with ATGL protein in the gluteal depot (P < 0.001).

Conclusions

GHR levels correlate with levels of lipases and lipid droplet‐associated proteins crucial for lipolysis. Thus, higher GHR expression in the abdominal depot when compared with the gluteal depot may underlie the in vivo effect of GH to specifically reduce abdominal adipose tissue mass.
Maternal caffeine intake during pregnancy, early growth, and body fat distribution at school age
Authors: Voerman Ellis , Jaddoe Vincent W.V. , Gishti Olta , Hofman Albert , Franco Oscar H. , Gaillard Romy
Published: March 2016

Objective

The associations of maternal caffeine intake during pregnancy with offspring growth patterns and body fat and insulin levels at school age were examined.

Methods

In a population‐based birth cohort among 7,857 mothers and their children, maternal caffeine intake during pregnancy was assessed by questionnaires. Growth characteristics were measured from birth onward. At 6 years, body fat and insulin levels were measured.

Results

Compared to children whose mothers consumed <2 units of caffeine per day during pregnancy (1 unit of caffeine is equivalent to 1 cup of coffee (90 mg caffeine)), those whose mothers consumed ≥6 units of caffeine per day tended to have a lower weight at birth, higher weight gain from birth to 6 years, and higher body mass index from 6 months to 6 years. Both children whose mothers consumed 4‐5.9 and ≥6 units of caffeine per day during pregnancy tended to have a higher childhood body mass index and total body fat mass. Only children whose mothers consumed ≥6 units of caffeine per day had a higher android/gynoid fat mass ratio.

Conclusions

These results suggest that high levels of maternal caffeine intake during pregnancy are associated with adverse offspring growth patterns and childhood body fat distribution.
Thermal analysis of kenaf fiber reinforced floreon biocomposites with magnesium hydroxide flame retardant filler
Authors: Lee C.H. , Sapuan S.M. , Hassan M.R.
Published: March 2016

The Floreon (FLO) biopolymer is an advanced bioplastic materials, invented by The University of Sheffield and CPD Plc, in November 2013. Nine combinations of the kenaf fiber (KF) reinforced FLO with magnesium hydroxide (MH) flame retardant filler were fabricated and tested on Thermogravimetry Analysis, Differential Scanning Calorimetry, and Dynamic Mechanical Analysis (DMA). Scanning electron microscopy has been used to study the cross‐section of interface. The low thermal stability of natural fiber composite has found lower decomposition temperature but a higher residual mass. MH filler containing composite has higher residual mass at 600°C but it is not the best flame retardant for the FLO biopolymer composites as the pure FLO biopolymer has higher decomposition temperature than MH reaction temperature. Some synergistic effect located in char formation, Tg reduction and a lower tan δ peak shown in the three phase system (KF/FLO/MH). The MH filler has found more significant in enhancing mass residual. The Tg were show deterioration for all samples compared with the pure FLO biopolymer. The melting temperature has found no significant change either KF or MH or both of these were inserted. The values of coefficient, C recorded decreasing as increasing the fiber loading. This showing the fibers transfer the loading effectively. Close value of storage moduli found in DMA for all samples except sample 4. POLYM. COMPOS., 39:869–875, 2018. © 2016 Society of Plastics Engineers
All‐cellulose composites from pineapple leaf microfibers: Structural, thermal, and mechanical properties
Authors: Tanpichai Supachok , Witayakran Suteera
Published: March 2016

Pineapple leaf microfibers (PALM) were used to prepare all‐cellulose composites using the surface selective dissolution method. Effect of dissolution times on mechanical and physical properties of the all‐cellulose composites was investigated. The structural transformation from cellulose I to cellulose II was observed when the fibers were dissolved in a mixed solution of lithium chloride (LiCl) and N,N‐dimethylacetamide (DMAc). Values of 42.8 MPa and 1.2 GPa for tensile strength and Young's modulus, respectively, were obtained from the composites with 120 min dissolution time in the LiCl/DMAc solution, whereas the tensile strength and Young's modulus of the undissolved PALM mats were found to be only 1.5 MPa and 0.1 GPa, respectively. The failure mechanism of the composites was changed from the fiber pull‐out to the fiber breakage when the dissolution time was longer. However, lower thermal stability and degree of crystallinity of the composites were caused by the change of the cellulose structure. The composites prepared in this work can be called as biodegradable materials, and could be the potential candidates to replace nonbiodegradable materials. POLYM. COMPOS., 39:895–903, 2018. © 2016 Society of Plastics Engineers
The detachment behavior of polycarbonate on thin films above the glass transition temperature
Authors: Tillmann W. , Hagen L. , Hoffmann F. , Dildrop M. , Wibbeke A. , Schöppner V. , Resonnek V. , Pohl M. , Krumm C. , Tiller J. C. , Paulus M. , Sternemann C.
Published: March 2016

When producing mono‐axially stretched films made of amorphous polycarbonate, a self‐reinforcement is generated due to the stretching process. This leads to an increase of the strength and stiffness. The mono‐axial stretching process is conducted at temperatures above the glass transition temperature, whereas better mechanical properties are obtained at higher stretching temperatures. However, the film tends to adhere to the rolls, especially at temperatures from 10°C above the glass transition temperature. The rolls of the mono‐axial stretching unit are made of an induction hardened and polished quenched and tempered steel 1.7225 – 42CrMo4. This work reports on the investigation of the detachment behavior of polycarbonate on different coatings as a function of the temperature and contact time. The main intention is to find a suitable coating on which the polycarbonate film adheres only slightly at temperatures clearly exceeding the glass transition temperature. POLYM. ENG. SCI., 56:786–797, 2016. © 2016 Society of Plastics Engineers
Cost‐Effectiveness of High‐Dose Edoxaban Compared with Adjusted‐Dose Warfarin for Stroke Prevention in Non–Valvular Atrial Fibrillation Patients
Authors: Nguyen Elaine , Egri Florence , Mearns Elizabeth S. , White Charles M. , Coleman Craig I.
Published: March 2016

Objective

To estimate the quality‐adjusted life‐years (QALYs), costs, and cost‐effectiveness of high‐dose edoxaban compared with adjusted‐dose warfarin in patients at risk for stroke who have nonvalvular atrial fibrillation (NVAF) and a creatinine clearance (Clcr) of 15–95 ml/minute.

Methods

A Markov model was created to compare the cost‐effectiveness of high‐dose edoxaban and adjusted‐dose warfarin in patients with a Clcrof 15–95 ml/minute. The model was performed from a U.S. societal perspective and assumed patients initiated therapy at 70 years of age, had a meanCHADS2(congestive heart failure, hypertension, age 75 or older, diabetes, stroke) score of 3, and no contraindications to anticoagulation. The model assumed a cycle length of 1 month and a lifetime horizon (maximum of 30 years/360 cycles). Data sources included renal subgroup analysis of the Effective Anticoagulation with Factor Xa Next Generation in Atrial Fibrillation (ENGAGE‐AF) trial and other published studies. Outcomes included lifetime costs (2014US$),QALYs, and incremental cost‐effectiveness ratios. The robustness of the model's conclusions was tested using one‐way and 10,000‐iteration probabilistic sensitivity analysis (PSA).

Results

Patients treated with high‐dose edoxaban lived an average of 10.50QALYs at a lifetime treatment cost of $99,833 compared with 10.11QALYs and $123,516 for those treated with adjusted‐dose warfarin. The model's conclusions were found to be robust upon one‐way sensitivity analyses.PSAsuggested high‐dose edoxaban was economically dominant compared with adjusted‐dose warfarin in more than 99% of the 10,000 iterations run.

Conclusions

High‐dose edoxaban appears to be an economically dominant strategy when compared with adjusted‐dose warfarin for the prevention of stroke inNVAFpatients with a Clcrof 15–95 ml/minute and an appreciable risk of stroke.
Thermosensitive behavior of amphiphilic triblock copolymers based on poly(acrylic acid) and poly(propylene oxide)
Authors: Pottier Christophe , Morandi Gaëlle , Rihouey Christophe , Dulong Virginie , Picton Luc , Le Cerf Didier
Published: March 2016

Self‐association in aqueous solution of amphiphilic poly(acrylic acid)‐b‐poly(propylene oxide)‐b‐poly(acrylic acid) (PAA‐b‐PPO‐b‐PAA) copolymers having various outer PAA block lengths are presented. These copolymers show two thermosensitive behaviors. The first one, due to hydrogen bonds between PAA and PPO resulting in large aggregates, was observed by visible spectroscopy. The second one, due to the association of PPO middle block into aggregates, was evidenced by dynamic light scattering and pyrene fluorescence. These critical temperatures both depend on the ionization and the length of PAA blocks. The characterization of the aggregates above the critical aggregation concentration by fluorescence quenching experiments showed a very low aggregation number corresponding to dimers or trimers association depending on the conditions. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 1507–1514
Recent advances in solid‐state NMR computational spectroscopy: The case of alumino‐silicate glasses
Authors: Pedone Alfonso
Published: March 2016

Solid‐state NMR spectroscopy and computational approaches such as Molecular Dynamics (MD) simulations and Density Functional Theory have proven to be very useful and versatile techniques for studying the structure and the dynamics of noncrystalline materials if a direct comparison between experiment and theory is established. In this review, the basic concepts in first‐principle modeling of solid‐state NMR spectra of oxide glasses are presented. There are three theoretical ingredients in the computational recipe. First, classical or ab initio molecular dynamics simulations are employed to generate the structural models of the glasses of interest. Second, periodic Density Functional Theory calculations coupled with the gauge including projector augmented‐wave (GIPAW) algorithm form the basis for the ab initio calculations of NMR parameters (chemical shielding and quadrupolar parameters). Finally, Spin‐effective Hamiltonian are employed to simulate the solid‐state NMR spectra directly comparable with the experimental counterparts. As an example of this methodology, the investigation of the local and medium range structure of Na‐Ca silicate and aluminosilicate glasses that are usually employed as simplified models for basaltic, andesitic and rhyolitic magmas will be reported. We will show how the direct comparison of the theoretical NMR spectra of MD derived structural models with the experimental counterparts allows gaining new insights into the atomistic structure of very complex oxide glasses. © 2016 Wiley Periodicals, Inc.
Concise Review: Advances in Generating Hepatocytes from Pluripotent Stem Cells for Translational Medicine
Authors: Szkolnicka Dagmara , Hay David C.
Published: March 2016

The liver is one of the major organs in the human body. Severe or prolonged exposure of the liver to different factors may cause life-threatening disease, which necessitates donor organ transplantation. While orthotopic liver transplantation can be used to effectively treat liver failure, it is an invasive procedure, which is severely limited by organ donation. Therefore, alternative sources of liver support have been proposed and studied. This includes the use of pluripotent stem cell-derived hepatocytes as a renewable source of cells for therapy. In addition to cell-based therapies, in vitro engineered liver tissue provides powerful models for human drug discovery and disease modeling. This review focuses on the generation of hepatocyte-like cells from pluripotent stem cells and their application in translational medicine.
Family Literacy Project
Authors: Louie Belinda , Davis‐Welton Karlyn
Published: March 2016

The purpose of this article is to describe a family literacy project involving a partnership of school‐aged children and their families with in‐service and pre‐service teachers enrolled in a university course on literacy instruction for English language learners. This project consists of family members sharing their stories with their children to be later transformed into bilingual picture books. This project engaged teachers, families, EL learners, and community members to become partners in students’ literacy development. Teachers engaged students from culturally‐ and linguistically‐diverse backgrounds and their families to produce student‐authored and self‐illustrated bilingual picture books in the classroom setting. In this article, we present the instructional process for teachers who are interested in partnering with families to create bilingual books.
Synthesis and Characterization of Novel Aryl Alkyl Sulfonates Based on Nonylphenol
Authors: Niu Ruixia , Wang Chao , Song Hua , Liao Lingzhi , Wang Jingling , Ren Weidong
Published: March 2016

A series of nonylphenol‐substituted alkyl sulfonates (Cx NPAS, x = 8, 10, 12, 14, 16) with two hydrocarbon chains and two different hydrophilic groups has been synthesized from α‐olefins and nonylphenol. The respective products have a “pseudo‐gemini” surfactant structure. The structures of the Cx NPAS have been characterized by IR, UV, 1H nuclear magnetic resonance, electrospray ionization mass spectrometry, and elemental analysis. The effects of carbon chain length of the obtained surfactants on properties such as the critical micelle concentrations (CMC) in aqueous solutions, surface tension at the CMC (γCMC), and efficiency of adsorption at the water/air interface (pC20) have been determined. The γCMC of the surfactants first decreased and then increased with increasing length of the carbon chain x, and reached a minimum of 29.25 mN/m at x = 10, which is much lower than that of α‐olefin sulfonate (AOS) (33.52 mN/m). The CMC decreased and pC20 increased with increasing x. The introduction of the hydroxyl group is responsible for multiple molecular conformations at the water/air interface and leads to a greater molecular area Amin and smaller Γmax than those of AOS.