bluuebunny/crossref_metadata_2025 huggingface dataset:
Trend changes in sympatric Subantarctic and Antarctic fur seal pup populations at Marion Island, Southern Ocean
Authors: Wege Mia , Etienne Marie‐Pierre , Chris Oosthuizen W. , Reisinger Ryan R. , Bester Marthán N. , de Bruyn P. J. Nico
Published: February 2016

Recent pup population estimates of sympatric Subantarctic (Arctocephalus tropicalis) and Antarctic fur seals (A. gazella) at Marion Island are presented. Published pup population estimates of A. tropicalis (1995 and 2004) with an unpublished total island count in 2013, and annual counts on subsets of rookeries (2007–2015) were analyzed using a hierarchical Bayesian model. The pup population declined by 46% (95% credible interval CI: 43%–48%) between 2004 (mean = 15,260, CI: 14,447–16,169 pups) and 2013 (mean = 8,312, CI: 7,983–8,697), mirrored by a 58%–60% decline at rookeries counted annually (2007–2015). Population decline was highest at high‐density west and north coast rookeries, despite negligible change in female attendance patterns, pup mortality or median pupping date over the previous 25 yr. A better understanding of foraging behavior and its effects on reproductive success and survival in this A. tropicalis population is needed before we can attribute population decline to any external factors. In contrast, total island counts of A. gazella pups in 2007, 2010, and 2013, suggest that this population is still increasing although the annual intrinsic rate of population growth decreased from 17.0% (1995–2004, 744 pups) to 4.0% (2010–2013, 1,553 pups). The slowed growth of A. gazella is likely the result of saturation at the main rookery.
Depredation of Patagonian toothfish (Dissostichus eleginoides) by two sympatrically occurring killer whale (Orcinus orca) ecotypes: Insights on the behavior of the rarely observed type D killer whales
Authors: Tixier Paul , Gasco Nicolas , Duhamel Guy , Guinet Christophe
Published: February 2016

Sympatric forms of ecologically distinctive killer whales (Orcinus orca) have been documented worldwide. This study focused on a new case of such sympatric occurrence of the “Crozet” type and the recently described “type D” killer whales off the Crozet Islands. The two ecotypes are morphologically and genetically distinct, but they both depredate the same local longline fishery. We used observational, photo‐identification, and fishing data, collected between 2003 and 2015, to examine differences in their patterns of depredation. Of the 828 sets where ecotype could be confirmed, type D killer whales interacted with 82 (11%) of the sets, including 9 (1%) sets that were simultaneously depredated by both ecotypes. Associations between the two types were never observed. Type D killer whales typically occurred in larger groups and both ecotypes preferentially depredated Patagonian toothfish (Dissostichus eleginoides). GLMM modeling revealed that the probability of type D depredation significantly increased throughout the study period, especially in deep waters, and photo‐identification data suggested that a subset of all individuals were habituating to depredation. This study documents the partitioning of resources between two distinct ecotypes of killer whales and provides preliminary insight into the feeding ecology of the rare type D killer whale.
Identifying developmental phases in the Arabidopsis thaliana rosette using integrative segmentation models
Authors: Lièvre Maryline , Granier Christine , Guédon Yann
Published: February 2016

The change in leaf size and shape during ontogeny associated with heteroblastic development is a composite trait for which extensive spatiotemporal data can be acquired using phenotyping platforms. However, only part of the information contained in such data is exploited, and developmental phases are usually defined using a selected organ trait. We here introduce new methods for identifying developmental phases in the Arabidopsis rosette using various traits and minimum a priori assumptions.

A pipeline of analysis was developed combining image analysis and statistical models to integrate morphological, shape, dimensional and expansion dynamics traits for the successive leaves of the Arabidopsis rosette. Dedicated segmentation models called semi‐Markov switching models were built for selected genotypes in order to identify rosette developmental phases.

Four successive developmental phases referred to as seedling, juvenile, transition and adult were identified for the different genotypes. We show that the degree of covering of the leaf abaxial surface with trichomes is insufficient to define these developmental phases.

Using our pipeline of analysis, we were able to identify the supplementary seedling phase and to uncover the structuring role of various leaf traits. This enabled us to compare on a more objective basis the vegetative development of Arabidopsis mutants.
The mechanisms whereby the green alga Chlorella ohadii, isolated from desert soil crust, exhibits unparalleled photodamage resistance
Authors: Treves Haim , Raanan Hagai , Kedem Isaac , Murik Omer , Keren Nir , Zer Hagit , Berkowicz Simon M. , Giordano Mario , Norici Alessandra , Shotland Yoram , Ohad Itzhak , Kaplan Aaron
Published: February 2016

Excess illumination damages the photosynthetic apparatus with severe implications with regard to plant productivity. Unlike model organisms, the growth of Chlorella ohadii, isolated from desert soil crust, remains unchanged and photosynthetic O2 evolution increases, even when exposed to irradiation twice that of maximal sunlight.

Spectroscopic, biochemical and molecular approaches were applied to uncover the mechanisms involved.

D1 protein in photosystem II (PSII) is barely degraded, even when exposed to antibiotics that prevent its replenishment. Measurements of various PSII parameters indicate that this complex functions differently from that in model organisms and suggest that C. ohadii activates a nonradiative electron recombination route which minimizes singlet oxygen formation and the resulting photoinhibition. The light‐harvesting antenna is very small and carotene composition is hardly affected by excess illumination. Instead of succumbing to photodamage, C. ohadii activates additional means to dissipate excess light energy. It undergoes major structural, compositional and physiological changes, leading to a large rise in photosynthetic rate, lipids and carbohydrate content and inorganic carbon cycling.

The ability of C. ohadii to avoid photodamage relies on a modified function of PSII and the dissipation of excess reductants downstream of the photosynthetic reaction centers. The biotechnological potential as a gene source for crop plant improvement is self‐evident.
A Historical Perspective on the Role of Functional Lines of Block in the Re‐entrant Circuit of Ventricular Tachycardia
Authors: PROIETTI RICCARDO , ROUX JEAN‐FRANCOIS , VERMA ATUL , ALTURKI AHMED , BERNIER MARTIN L. , ESSEBAG VIDAL
Published: February 2016

The ablation strategy for ventricular tachycardia (VT) rapidly evolved from an entrainment mapping approach for identification of the critical isthmus of the re‐entrant circuit during monomorphic VT, toward a substrate‐based approach aiming to ablate surrogate markers of the circuit during sinus rhythm in hemodynamically nontolerated and polymorphic VT. The latter approach implies an assumption that the circuits responsible for the arrhythmia are anatomical or fixed, and present during sinus rhythm. Accordingly, the lines of block delimiting the channels of the circuits are often considered fixed, although there is evidence that they are functional or more frequently a combination of fixed and functional. The electroanatomical substrate‐based approach to VT ablation performed during sinus rhythm is increasingly adopted in clinical practice and often described as scar homogenization, scar dechanneling, or core isolation. However, whether the surrogate markers of the VT circuit during sinus rhythm match the circuit during arrhythmias remains to be fully demonstrated. The myocardial scar is a heterogeneous electrophysiological milieu with complex arrhythmogenic mechanisms that potentially coexist simultaneously. Moreover, the scar consists of different areas of diverse refractoriness and conduction. It can be misleading to limit the arrhythmogenic perspective of the myocardial scar to fixed or anatomical barriers held responsible for the re‐entry circuit. Greater understanding of the role of functional lines of block in VT and the validity of the surrogate targets being ablated is necessary to further improve the technique and outcome of VT ablation.
Rectus sheath and transversus abdominis plane blocks in children: a systematic review and meta‐analysis of randomized trials
Authors: Hamill James K. , Rahiri Jamie‐Lee , Liley Andrew , Hill Andrew G.
Published: February 2016

Introduction

The role of rectus sheath blocks (RSB) and transversus abdominis plane (TAP) blocks in pediatric surgery has not been well established.

Objective

We aimed to determine if RSB and TAP blocks decrease postoperative pain and improve recovery in children.

Data sources

Duplicate searching of MEDLINE, EMBASE, Cochrane, Web of Science, and trial registries databases by two reviewers.

Study selection

Included were randomized trials in children on RSB or TAP block in abdominal operations, excluding inguinal procedures.

Data extraction

Independent duplicate data extraction and quality assessment using a standardized form.

Results

Ten trials met inclusion criteria (n = 599), RSB in five and TAP block in five. A linear mixed effects model on patient level data from three trials showed nerve blocks lowered morphine requirements 6–8 h after surgery, −0.03 mg·kg−1 (95% CI −0.05, −0.002). Pooled analysis of summary data showed nerve blocks lowered 0–10 scale pain scores immediately after the operation, −0.7 (95% CI −1.3, −0.1); lowered 4–16 scale pain scores, −2.0 (95% CI −2.3, −1.7); and delayed the time to first rescue analgesia, 17 min (95% CI 1.3, 33). Quality assessment showed some studies at moderate to high risk of bias.

Conclusion

Abdominal wall blocks reduce pain and opiate use in children. We advise cautious interpretation of the results given the heterogeneity of studies.
NAD(P)H dehydrogenase, quinone 1 (NQO1), protects melanin‐producing cells from cytotoxicity of rhododendrol
Authors: Okubo Ayaka , Yasuhira Shinji , Shibazaki Masahiko , Takahashi Kazuhiro , Akasaka Toshihide , Masuda Tomoyuki , Maesawa Chihaya
Published: February 2016

Rhododendrol (RD) is a potent tyrosinase inhibitor that is metabolized to RD‐quinone by tyrosinase, which may underlie the cytotoxicity of RD and leukoderma of the skin that may result. We have examined how forced expression of the NAD(P)H quinone dehydrogenase, quinone 1 (NQO1), a major quinone‐reducing enzyme in cytosol, affects the survival of RD‐treated cells. We found that treatment of the mouse melanoma cell line B16BL6 or normal human melanocytes with carnosic acid, a transcriptional inducer of the NQO1 gene, notably suppressed the cell killing effect of RD. This effect was mostly abolished by ES936, a highly specific NQO1 inhibitor. Moreover, conditional overexpression of the human NQO1 transgene in B16BL6 led to an expression‐dependent increase of cell survival after RD treatment. Our results suggest that NQO1 attenuates the cytotoxicity of RD and/or its metabolites.
Knowledge of Vaccination Needs of HIV‐Infected Men Who Have Sex with Men in a National Sample of “Gay Friendly” Health care Providers
Authors: Blackwell Christopher W.
Published: February 2016

Objectives

The purpose of this study was to assess knowledge levels regarding vaccination needs of healthy, HIV‐infected (with CD4 counts >200 cells/mm3) men who have sex with men (MSM) in a national sample of “gay friendly” health providers.

Design and Sample

Participants (n = 92) were sent a demographic questionnaire and case vignette asking for correct identification of vaccine needs of an HIV‐infected MSM with a CD4 count >200 cells/mm3. Participants were recruited from the Gay and Lesbian Medical Association's Health Provider Index.

Measures

Descriptive statistics and Fisher's exact test were used to answer the research questions and define the sample.

Results

The vast majority of the sample (n = 83; 90%) misidentified correct vaccine needs of and/or selected inappropriate vaccines for the HIV‐infected MSM. Greater familiarity with the CDC Adult Vaccination Schedule (p = .027), practice specialization (p = .004), and administration of vaccinations within location of practice (p = .009) were associated with greater knowledge of the patient's vaccine needs.

Conclusions

Health care providers who prescribe vaccines to HIV‐infected MSM need more education regarding their vaccine needs. Nurses can reduce disparities in HIV‐infected MSM by advocating for vaccination and augmenting providers' comprehension of vaccine needs of this population.
Low‐Income Immigrant Hispanic Mothers' Concerns and Perceptions of Their Young Child's Weight
Authors: Hernandez Daphne C. , Reesor Layton , Machuca Iris , Chishty Misha , Alonso Yanely
Published: February 2016

Objectives

To describe how low‐income Hispanic immigrant mothers' concerns and perceptions of her child's health, along with her concerns for herself becoming overweight, relate to her (a) concerns that her child will become overweight and (b) underestimation of her child's weight status.

Design and Sample

Cross‐sectional survey and direct body composition assessments were collected among 96 low‐income Hispanic mothers and their young children from Houston‐area community centers.

Measures

Data were collected on maternal concerns and perceptions of child's weight and health, concerns about her own weight, demographic characteristics, and measured child's height and weight.

Results

Fifty‐four percent of mothers with an overweight/obese child perceived their child was “about the right weight.” Mothers concerned with becoming overweight themselves had 3 times higher odds of being concerned that her child would become overweight (OR = 3.01, p < .01). Mothers who perceived their child as less healthy had approximately 2 times higher odds of underestimating their child's weight (OR = 1.86, p < .01).

Conclusions

Short screeners that focus on maternal concerns about herself and her child becoming overweight, along with perceptions of her child's health and weight status, may assist nurses in effectively tailoring their health message at point of care.
Event‐related potential indices of congruency sequence effects without feature integration or contingency learning confounds
Authors: Larson Michael J. , Clayson Peter E. , Kirwan C. Brock , Weissman Daniel H.
Published: February 2016

The congruency effect in Stroop‐like tasks (i.e., increased response time and reduced accuracy in incongruent relative to congruent trials) is often smaller when the previous trial was incongruent as compared to congruent. This congruency sequence effect (CSE) is thought to reflect cognitive control processes that shift attention to the target and/or modulate the response engendered by the distracter differently after incongruent relative to congruent trials. The neural signatures of CSEs are therefore usually attributed to cognitive control processes that minimize distraction from irrelevant stimuli. However, CSEs in previous functional neuroimaging studies were ubiquitously confounded with feature integration and/or contingency learning processes. We therefore investigated whether a neural CSE can be observed without such confounds in a group of healthy young adults (n = 56). To this end, we combined a prime‐probe task that lacks such confounds with high‐density ERPs to identify, for the first time, the neural time course of confound‐minimized CSEs. Replicating recent behavioral findings, we observed strong CSEs in this task for mean response time and mean accuracy. Critically, conceptually replicating prior ERP results from confounded tasks, we also observed a CSE in both the parietal conflict slow potential (conflict SP) and the frontomedial N450. These findings indicate for the first time that neural CSEs as indexed by ERPs can be observed without the typical confounds. More broadly, the present study provides a confound‐minimized protocol that will help future researchers to better isolate the neural bases of control processes that minimize distraction from irrelevant stimuli.
Impacts of environmental and biological stressors on immune system ofMacrobrachium rosenbergii
Authors: Kumaresan Venkatesh , Palanisamy Rajesh , Pasupuleti Mukesh , Arockiaraj Jesu
Published: February 2016

Macrobrachium rosenbergiicommonly called giant freshwater prawn is a widely farmed crustacean in freshwater. Similar to other aquatic organisms, their growth and well‐being is influenced by various physical, chemical and biological factors. We discuss about the critical growth limiting factors as well as disease causing agents and the potential immune molecules ofM. rosenbergiithat are proved to involve in preventing and/or responding to those limiting factors.
Tutorial: Parallel Computing of Simulation Models for Risk Analysis
Authors: Reilly Allison C. , Staid Andrea , Gao Michael , Guikema Seth D.
Published: February 2016

Simulation models are widely used in risk analysis to study the effects of uncertainties on outcomes of interest in complex problems. Often, these models are computationally complex and time consuming to run. This latter point may be at odds with time‐sensitive evaluations or may limit the number of parameters that are considered. In this article, we give an introductory tutorial focused on parallelizing simulation code to better leverage modern computing hardware, enabling risk analysts to better utilize simulation‐based methods for quantifying uncertainty in practice. This article is aimed primarily at risk analysts who use simulation methods but do not yet utilize parallelization to decrease the computational burden of these models. The discussion is focused on conceptual aspects of embarrassingly parallel computer code and software considerations. Two complementary examples are shown using the languages MATLAB and R. A brief discussion of hardware considerations is located in the Appendix.
Epidermal changes during UVB phototherapy assessed by multiphoton laser tomography
Authors: Koehler M. J. , Kellner K. , Kaatz M. , Hipler U.‐C.
Published: February 2016

Background

Multiphoton laser tomography (MPT) is a non‐invasive technique that allows imaging of skin in vivo with very high spatial resolution and contrast. Previous work of our group has demonstrated that known morphological changes due to erythematogenic ultraviolet B (UVB) irradiation may be imaged in vivo by MPT. The present work investigated if morphological skin changes known from experimental erythematogenic UVB irradiation are also demonstrable in the course of a standard phototherapy regime that implies suberythematogenic doses of narrow band UVB.

Methods

Sixteen patients with psoriasis vulgaris receiving a narrow band phototherapy were included. A test field and a light‐protected control field were measured with the multiphoton tomograph DermaInspect® at four time points: at baseline, the next day, after 3 days and at the day of the last exposure.

Results

In the course of the UVB phototherapy, spongiosis and pleomorphy as parameters of inflammation and cellular damage did not show significant changes. By contrast, an adaptive skin reaction with significant changes of keratosis and pigmentation was observed.

Conclusion

MPT is a suitable technique for the investigation of qualitative and quantitative skin changes after UVB irradiation. After suberythematogenic UVB irradiation, photoadaptive skin changes, but no cellular damage can be observed with MPT.
Nuclear accumulation of myocyte muscle LIM protein is regulated by heme oxygenase 1 and correlates with cardiac function in the transition to failure
Authors: Paudyal Anju , Dewan Sukriti , Ikie Cindy , Whalley Benjamin J , de Tombe Pieter P. , Boateng Samuel Y.
Published: February 2016

Key points

The present study investigated the mechanism associated with impaired cardiac mechanosensing that leads to heart failure by examining the factors regulating muscle LIM protein subcellular distribution in myocytes.

In myocytes, muscle LIM protein subcellular distribution is regulated by cell contractility rather than passive stretch via heme oxygenase‐1 and histone deacetylase signalling. The result of the present study provide new insights into mechanotransduction in cardiac myocytes.

Myocyte mechanosensitivity, as indicated by the muscle LIM protein ratio, is also correlated with cardiac function in the transition to failure in a guinea‐pig model of disease. This shows that the loss mechanosensitivity plays an important role during the transition to failure in the heart.

The present study provides the first indication that mechanosensing could be modified pharmacologically during the transition to heart failure.

Impaired mechanosensing leads to heart failure and a decreased ratio of cytoplasmic to nuclear CSRP3/muscle LIM protein (MLP ratio) is associated with a loss of mechanosensitivity. In the present study, we tested whether passive or active stress/strain was important in modulating the MLP ratio and determined whether this correlated with heart function during the transition to failure. We exposed cultured neonatal rat myocytes to a 10% cyclic mechanical stretch at 1 Hz, or electrically paced myocytes at 6.8 V (1 Hz) for 48 h. The MLP ratio decreased by 50% (P < 0.05, n = 4) only in response to electrical pacing, suggesting impaired mechanosensitivity. Inhibition of contractility with 10 μm blebbistatin resulted in an ∼3‐fold increase in the MLP ratio (n = 8, P < 0.05), indicating that myocyte contractility regulates nuclear MLP. Inhibition of histone deacetylase (HDAC) signalling with trichostatin A increased nuclear MLP following passive stretch, suggesting that HDACs block MLP nuclear accumulation. Inhibition of heme oxygenase1 (HO‐1) activity with protoporphyrin IX zinc(II) blocked MLP nuclear accumulation. To examine how mechanosensitivity changes during the transition to heart failure, we studied a guinea‐pig model of angiotensin II infusion (400 ng kg–1 min–1) over 12 weeks. Using subcellular fractionation, we showed that the MLP ratio increased by 88% (n = 4, P < 0.01) during compensated hypertrophy but decreased significantly during heart failure (P < 0.001, n = 4). The MLP ratio correlated significantly with the E/A ratio (r = 0.71, P < 0.01, n = 12), a clinical measure of diastolic function. These data indicate for the first time that myocyte mechanosensitivity as indicated by the MLP ratio is regulated primarily by myocyte contractility via HO‐1 and HDAC signalling.
Optimizing sample preparation for anatomical determination in the hippocampus of rodent brain by ToF-SIMS analysis
Authors: Angerer Tina B. , Mohammadi Amir Saeid , Fletcher John S.
Published: February 2016

Lipidomics has been an expanding field since researchers began to recognize the signaling functions of lipids and their involvement in disease. Time-of-flight secondary ion mass spectrometry is a valuable tool for studying the distribution of a wide range of lipids in multiple brain regions, but in order to make valuable scientific contributions, one has to be aware of the influence that sample treatment can have on the results. In this article, the authors discuss different sample treatment protocols for rodent brain sections focusing on signal from the hippocampus and surrounding areas. The authors compare frozen hydrated analysis to freeze drying, which is the standard in most research facilities, and reactive vapor exposure (trifluoroacetic acid and NH3). The results show that in order to preserve brain chemistry close to a native state, frozen hydrated analysis is the most suitable, but execution can be difficult. Freeze drying is prone to produce artifacts as cholesterol migrates to surface, masking other signals. This effect can be partially reversed by exposing freeze dried sections to reactive vapor. When analyzing brain sections in negative ion mode, exposing those sections to NH3 vapor can re-establish the diversity in lipid signal found in frozen hydrated analyzed sections. This is accomplished by removing cholesterol and uncovering sulfatide signals, allowing more anatomical regions to be visualized.
Reduce the matrix effect in biological tissue imaging using dynamic reactive ionization and gas cluster ion beams
Authors: Tian Hua , Wucher Andreas , Winograd Nicholas
Published: February 2016

In the context of a secondary ion mass spectrometry (SIMS) experiment, dynamic reactive ionization (DRI) involves introducing a reactive dopant, HCl, into an Ar gas cluster primary ion beam along with a source of water to enable dissociation of HCl to free protons. This concerted effect, precisely occurring at the impact site of the cluster beam, enhances the protonation of molecular species. Here, the authors apply this methodology to study the hippocampus and cerebellum region of a frozen-hydrated mouse brain section. To determine the degree of enhancement associated with DRI conditions, sequential tissue slices were arranged in a mirrored configuration so that comparable regions of the tissue could be explored. The results show that the protonated lipid species are increased by ∼10-fold, but that the normally prevalent salt adducts are virtually unaffected. This observation is discussed as a novel approach to minimizing SIMS matrix effects in complex materials. Moreover, the chemical images of protonated lipid ions exhibit clearer features in the cerebellum region as compared to images acquired with the pure Ar cluster beam.
Negative hydrocarbon species C2nH−: How useful can they be?
Authors: Nie Heng-Yong
Published: February 2016

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) analyzes chemical information by measuring ions generated via bombardment of an energetic ion beam on the surface of a specimen. Negative hydrocarbon ion species of C2nH− are ubiquitous in TOF-SIMS for any hydrocarbon-containing materials, but their utilities are perhaps not fully explored. Using polyethylene, polypropylene, polyisoprene, and polystyrene, the author demonstrates that C2nH− species possess intrinsic relationships, which offers unique TOF-SIMS ability for quantitatively differentiating the chemical structures of the four polymers.
Good grades for Germany's project to build an Ivy League
Authors: Vogel Gretchen
Published: February 2016

The Excellence Initiative is on the right track, a panel says.
Karolinska to reopen inquiry into surgeon's work
Authors: Vogel Gretchen
Published: February 2016

Television documentary raises new questions about Paolo Macchiarini's trachea implants.
Alfred Gilman (1941–2015)
Authors: Simon Melvin
Published: February 2016

A Nobel laureate's work on G proteins illuminated how signals are transmitted into cells
Draft Genome Sequence of Brevibacillus choshinensis HPD52
T
(DSM 8552), a Bacterial Host for Efficient Expression of Heterologous Proteins
Authors: Wang Jie-ping , Liu Bo , Liu Guo-hong , Che Jian-mei , Chen Zheng , Chen Meichun , Shi Huai
Published: February 2016

Brevibacillus choshinensis
HPD52
T
(DSM 8552) is a Gram-positive, spore-forming, and protein-producing bacterium. Here, we report the 6.28-Mb draft genome sequence of
B. choshinensis
HPD52
T
, which will promote its application and provide useful information for genomic taxonomy and phylogenomics of
Bacillus
-like bacteria.
Risk of acute kidney injury associated with neuroimaging obtained during triage and treatment of patients with acute ischemic stroke symptoms
Authors: Hall Shelby L , Munich Stephan A , Cress Marshall C , Rangel-Castilla Leonardo , Levy Elad I , Snyder Kenneth V , Siddiqui Adnan H
Published: February 2016

Background

Combining non-contrast CT (NCCT), CT angiography (CTA), and CT perfusion (CTP) imaging (referred to as a CT stroke study, CTSS) provides a rapid evaluation of the cerebrovascular axis during acute ischemic stroke. Iodinated contrast-enhanced CT imaging is not without risk, which includes renal injury. If a patient's CTSS identifies vascular pathology, digital subtraction angiography (DSA) is often performed within 24–48 h. Such patients may receive multiple administrations of iodinated contrast material over a short time period.

Objective

We aimed to evaluate the incidence of acute kidney injury (AKI) in patients who underwent a CTSS and DSA for evaluation of acute ischemic symptoms or for stroke intervention within a 48 h period between August 2012 and December 2014.

Methods

We identified 84 patients for inclusion in the analysis. Patients fell into one of two cohorts: AKI, defined as a rise in the serum creatinine level of ≥0.5 mg/dL from baseline, or non-AKI. Clinical parameters included pre- and post-imaging serum creatinine level, time between CTSS and DSA, and type of angiographic procedure (diagnostic vs intervention) performed.

Results

Four patients (4.7%) experienced AKI, one of whom had baseline renal dysfunction (defined as baseline serum creatinine level ≥1.5 mg/dL). The mean difference between baseline and peak creatinine values was found to be significantly greater in patients with AKI than in non-AKI patients (1.65 vs −0.09, respectively; p=0.0008).

Conclusions

This study provides preliminary evidence of the safety and feasibility of obtaining CTSS with additional DSA imaging, whether for diagnosis or intervention, to identify possible acute ischemic stroke.
Body composition and energy intake — skeletal muscle mass is the strongest predictor of food intake in obese adolescents: The HEARTY trial
Authors: Cameron Jameason D. , Sigal Ronald J. , Kenny Glen P. , Alberga Angela S. , Prud’homme Denis , Phillips Penny , Doucette Steve , Goldfield Gary
Published: February 2016

There has been renewed interest in examining the relationship between specific components of energy expenditure and the overall influence on energy intake (EI). The purpose of this cross-sectional analysis was to determine the strongest metabolic and anthropometric predictors of EI. It was hypothesized that resting metabolic rate (RMR) and skeletal muscle mass would be the strongest predictors of EI in a sample of overweight and obese adolescents. 304 post-pubertal adolescents (91 boys, 213 girls) aged 16.1 (±1.4) years with body mass index at or above the 95th percentile for age and sex OR at or above the 85th percentile plus an additional diabetes risk factor were measured for body weight, RMR (kcal/day) by indirect calorimetry, body composition by magnetic resonance imaging (fat free mass (FFM), skeletal muscle mass, fat mass (FM), and percentage body fat), and EI (kcal/day) using 3 day food records. Body weight, RMR, FFM, skeletal muscle mass, and FM were all significantly correlated with EI (p < 0.005). After adjusting the model for age, sex, height, and physical activity, only FFM (β = 21.9, p = 0.007) and skeletal muscle mass (β = 25.8, p = 0.02) remained as significant predictors of EI. FFM and skeletal muscle mass also predicted dietary protein and fat intake (p < 0.05), but not carbohydrate intake. In conclusion, with skeletal muscle mass being the best predictor of EI, our results support the hypothesis that the magnitude of the body’s lean tissue is related to absolute levels of EI in a sample of inactive adolescents with obesity.
A review of paleobotanical studies of the Early Eocene Okanagan (Okanogan) Highlands floras of British Columbia, Canada, and Washington, USA
Authors: Greenwood David R. , Pigg Kathleen B. , Basinger James F. , DeVore Melanie L.
Published: February 2016

The history of plant fossil collecting in the Okanagan (Okanogan) Highlands of British Columbia and northeastern Washington is closely intertwined with the history of geological surveys and mining activities from the 1870s onward. The first descriptions of fossil plants from British Columbia were published in 1870–1920 by J.W. Dawson, G.M. Dawson, and D.P. Penhallow. In the United States, fossil leaves and fish were first recognized at Republic, Washington, by miners in the early 1900s. Many early workers considered these floras to be of Oligocene or Miocene age. C.A. Arnold described Canadian occurrences of conifers and Azolla in the 1950s. Palynological studies in the 1960s by L.V. Hills, G.E. Rouse, and others and those of fossil fish by M.V.H. Wilson in the 1970–1980s provided the framework for paleobotanical research at several key localities. Permineralized plants were first described from the Princeton chert in the 1970s by C.N. Miller, J.F. Basinger, and others, followed by R.A. Stockey and her students. W.C. Wehr and K.R. Johnson revitalized the study of fossils at Republic with the discovery of a diverse assemblage in 1977. In 1987, J.A. Wolfe and Wehr produced a United States Geological Survey monograph on Republic, and Wehr cofounded the Stonerose Interpretive Center as a venue for public collecting. Systematic studies of the Okanagan Highlands plants, as well as paleoecological and paleoclimate reconstructions from palynomorphs and leaf floras, continue to expand our understanding of this important Early Eocene assemblage.
Environmental Sustainability of Mega-City: Technology Possibility and Boundary Rigidity
Authors: PAN Jiahua
Published: February 2016

Environmental governance of city hinges on the balance between technology possibility and rigid constraints of boundaries. Environmental carrying capacity of city constitutes rigid constraints of boundaries. The multiplier effect, incremental effect, and substitution effect of technology efficiently break through the constraints of environmental capacity posed upon city development, enable continuous expansion of city size, and lead to increasing amount and size of mega-cities. Nevertheless, rebound effect, accelerating effect, and ultimate effect of technology innovation also imposes limitations upon expansion of environmental carrying capacity and has negative effects on city operation and sustainability. Boundaries of mega-city cannot be broken though by technology possibility because of natural, social, and economic rigidity. Alternative solutions beyond technology, such as reformations and innovations on socio-economic and institutional mechanisms, should be concerned in the context of technical bottleneck of environmental governance of mega-city.
Fast Zeta Transforms for Lattices with Few Irreducibles
Authors: Björklund Andreas , Husfeldt Thore , Kaski Petteri , Koivisto Mikko , Nederlof Jesper , Parviainen Pekka
Published: February 2016

We investigate fast algorithms for changing between the standard basis and an orthogonal basis of idempotents for Möbius algebras of finite lattices. We show that every lattice with
v
elements,
n
of which are nonzero and join-irreducible (or, by a dual result, nonzero and meet-irreducible), has arithmetic circuits of size
O
(
vn
) for computing the zeta transform and its inverse, thus enabling fast multiplication in the Möbius algebra. Furthermore, the circuit construction in fact gives optimal (up to constants) monotone circuits for several lattices of combinatorial and algebraic relevance, such as the lattice of subsets of a finite set, the lattice of set partitions of a finite set, the lattice of vector subspaces of a finite vector space, and the lattice of positive divisors of a positive integer.
Bypassing UGC from Some Optimal Geometric Inapproximability Results
Authors: Guruswami Venkatesan , Raghavendra Prasad , Saket Rishi , Wu Yi
Published: February 2016

The Unique Games Conjecture (UGC) has emerged in recent years as the starting point for several optimal inapproximability results. While for
none
of these results a reverse reduction to Unique Games is known, the assumption of bijective projections in the Label Cover instance nevertheless seems critical in these proofs. In this work, we bypass the need for UGC assumption in inapproximability results for two geometric problems, obtaining a tight NP-hardness result in each case.

The first problem, known as

L
p

Subspace Approximation, is a generalization of the classic least squares regression problem. Here, the input consists of a set of points
X
= {α
1
, … , α
m
} ⊆ R

n

and a parameter
k
(possibly depending on
n
). The goal is to find a subspace
H
of
R

n

of dimension
k
that minimizes the ℓ

p

norm of the Euclidean distances to the points in
X
. For
p
= 2,
k
=
n
− 1, this reduces to the least squares regression problem, while for
p
= ∞,
k
= 0 it reduces to the problem of finding a ball of minimum radius enclosing all the points. We show that for any fixed
p
∈ (2, ∞), and for
k
=
n
− 1, it is NP-hard to approximate this problem to within a factor of γ

p

− ϵ for constant ϵ > 0, where γ

p

is the
p
th norm of a standard Gaussian random variable. This matches the γ

p

approximation algorithm obtained by Deshpande, Tulsiani, and Vishnoi who also showed the same hardness result under the UGC.

The second problem we study is the related

L
p

Quadratic Grothendieck Maximization Problem, considered by Kindler, Naor, and Schechtman. Here, the input is a multilinear quadratic form ∑

n

i
,
j
= 1

a
ij
x
i
x
j

and the goal is to maximize the quadratic form over the ℓ

p

unit ball, namely, all
x
with ∑

n

i
= 1

|

x
i

|

p

⩽ 1. The problem is polynomial time solvable for
p
= 2. We show that for any constant
p
∈ (2, ∞), it is NP-hard to approximate the quadratic form to within a factor of γ
2

p

− ϵ for any ϵ > 0. The same hardness factor was shown under the UGC by Kindler et al. We also obtain a γ
2

p

-approximation algorithm for the problem using the convex relaxation of the problem defined by Kindler et al. A γ
2

p

approximation algorithm has also been independently obtained by Naor and Schechtman.

These are the
first
approximation thresholds, proven under P ≠ NP, that involve the Gaussian random variable in a fundamental way. Note that the problem statements themselves do not explicitly involve the Gaussian distribution.
A Spatial-Temporal QoS Prediction Approach for Time-aware Web Service Recommendation
Authors: Wang Xinyu , Zhu Jianke , Zheng Zibin , Song Wenjie , Shen Yuanhong , Lyu Michael R.
Published: February 2016

Due to the popularity of service-oriented architectures for various distributed systems, an increasing number of Web services have been deployed all over the world. Recently, Web service recommendation became a hot research topic, one that aims to accurately predict the quality of functional satisfactory services for each end user. Generally, the performance of Web service changes over time due to variations of service status and network conditions. Instead of employing the conventional temporal models, we propose a novel spatial-temporal QoS prediction approach for time-aware Web service recommendation, where a sparse representation is employed to model QoS variations. Specifically, we make a zero-mean Laplace prior distribution assumption on the residuals of the QoS prediction, which corresponds to a Lasso regression problem. To effectively select the nearest neighbor for the sparse representation of temporal QoS values, the geo-location of web service is employed to reduce searching range while improving prediction accuracy. The extensive experimental results demonstrate that the proposed approach outperforms state-of-art methods with more than 10% improvement on the accuracy of temporal QoS prediction for time-aware Web service recommendation.
Label Cover Instances with Large Girth and the Hardness of Approximating Basic
k
-Spanner
Authors: Dinitz Michael , Kortsarz Guy , Raz Ran
Published: February 2016

We study the well-known
Label Cover
problem under the additional requirement that problem instances have large girth. We show that if the girth is some
k
, the problem is roughly 2

log
1-ϵ
n)/k

hard to approximate for all constant ϵ > 0. A similar theorem was claimed by Elkin and Peleg [2000] as part of an attempt to prove hardness for the basic
k
-spanner problem, but their proof was later found to have a fundamental error. Thus, we give both
the first
nontrivial lower bound for the problem of Label Cover with large girth as well as the first full proof of strong hardness for the basic
k
-spanner problem, which is both the simplest problem in graph spanners and one of the few for which super-logarithmic hardness was not known. Assuming
NP
⊆
BPTIME
(2

polylog(n)

, we show (roughly) that for every
k
⩾ 3 and every constant ϵ > 0, it is hard to approximate the basic
k
-spanner problem within a factor better than 2

log
1-ϵ
n)/k

. This improves over the previous best lower bound of only Ω(log
n
)/
k
from Kortsarz [2001]. Our main technique is subsampling the edges of 2-query probabilistically checkable proofs (PCPs), which allows us to reduce the degree of a PCP to be essentially equal to the soundness desired. This turns out to be enough to basically guarantee large girth.
A Tensor-Based Information Framework for Predicting the Stock Market
Authors: Li Qing , Chen Yuanzhu , Jiang Li Ling , Li Ping , Chen Hsinchun
Published: February 2016

To study the influence of information on the behavior of stock markets, a common strategy in previous studies has been to concatenate the features of various information sources into one compound feature vector, a procedure that makes it more difficult to distinguish the effects of different information sources. We maintain that capturing the intrinsic relations among multiple information sources is important for predicting stock trends. The challenge lies in modeling the complex space of various sources and types of information and studying the effects of this information on stock market behavior. For this purpose, we introduce a tensor-based information framework to predict stock movements. Specifically, our framework models the complex investor information environment with tensors. A global dimensionality-reduction algorithm is used to capture the links among various information sources in a tensor, and a sequence of tensors is used to represent information gathered over time. Finally, a tensor-based predictive model to forecast stock movements, which is in essence a high-order tensor regression learning problem, is presented. Experiments performed on an entire year of data for China Securities Index stocks demonstrate that a trading system based on our framework outperforms the classic Top-
N
trading strategy and two state-of-the-art media-aware trading algorithms.
A Survey of Techniques for Architecting and Managing Asymmetric Multicore Processors
Authors: Mittal Sparsh
Published: February 2016

To meet the needs of a diverse range of workloads, asymmetric multicore processors (AMPs) have been proposed, which feature cores of different microarchitecture or ISAs. However, given the diversity inherent in their design and application scenarios, several challenges need to be addressed to effectively architect AMPs and leverage their potential in optimizing both sequential and parallel performance. Several recent techniques address these challenges. In this article, we present a survey of architectural and system-level techniques proposed for designing and managing AMPs. By classifying the techniques on several key characteristics, we underscore their similarities and differences. We clarify the terminology used in this research field and identify challenges that are worthy of future investigation. We hope that more than just synthesizing the existing work on AMPs, the contribution of this survey will be to spark novel ideas for architecting future AMPs that can make a definite impact on the landscape of next-generation computing systems.
Subspace Frequency Analysis--Based Field Indices Extraction for Electricity Customer Classification
Authors: Piao Minghao , Ryu Keun Ho
Published: February 2016

In electricity customer classification, the most important task is to avoid the curse of dimensionality problem, as the consumption diagrams have a large number of dimensions. To avoid the curse of dimensionality problem,
field indices
(load shape factor) are often used instead of consumption diagrams. Field indices are directly extracted from consumption diagrams according to a predefined formula. Previous studies show that the most important thing for defining such a formula is to find meaningful time intervals from consumption diagrams. However, the inconvenient thing is that there are still a lack of details to explain how to define such time intervals.

In our study, we propose a data mining--based method named
SFATIE
to support the extraction of field indices. The performance of the proposed method is evaluated by comparing it with other dimensionality reduction methods during the classification. For the classification, most often we have used classification methods like C5.0, SVM, Neural Net, Bayes Net, and Logistic. The experimental results show that our method is better or close to other dimensionality reduction methods. In addition, the experimental results show that our proposed method can produce the good quality of field indices and that these indices can improve the performance of electricity customer classification.
Flipped classrooms and student learning: not just surface gains
Authors: McLean Sarah , Attardi Stefanie M. , Faden Lisa , Goldszmidt Mark
Published: February 2016

The flipped classroom is a relatively new approach to undergraduate teaching in science. This approach repurposes class time to focus on application and discussion; the acquisition of basic concepts and principles is done on the students' own time before class. While current flipped classroom research has focused on student preferences and comparative learning outcomes, there remains a lack of understanding regarding its impact on students' approaches to learning. Focusing on a new flipped classroom-based course for basic medical sciences students, the purpose of the present study was to evaluate students' adjustments to the flipped classroom, their time on task compared with traditional lectures, and their deep and active learning strategies. Students in this course worked through interactive online learning modules before in-class sessions. Class time focused on knowledge application of online learning module content through active learning methods. Students completed surveys and optional prequiz questions throughout the term to provide data regarding their learning approaches. Our results showed that the majority of students completed their prework in one sitting just before class. Students reported performing less multitasking behavior in the flipped classroom compared with lecture-based courses. Students valued opportunities for peer-peer and peer-instructor interactions and also valued having multiple modes of assessment. Overall, this work suggests that there is the potential for greater educational gains from the flipped classroom than the modest improvements in grades previously demonstrated in the literature; in this implementation of the flipped classroom, students reported that they developed independent learning strategies, spent more time on task, and engaged in deep and active learning.