bluuebunny/crossref_metadata_2025_split huggingface dataset:
Understanding the relationships between interest in online math games and academic performance
Authors: Zhang M. 
Published: August 2014

AbstractAlthough the Internet is widely used by students in both formal and informal environments, little is known about how and where youth spend their time online. Using Internet search and Web analytics data, this study discovered a large‐scale phenomenon associated with the poor performance of elementary school students in the USA that has been overlooked by educational researchers. This study found that approximately 10 million Internet users in the USA, many of whom are presumably youth, spend about 89 million hours in a year on a popular math game site that targets children. The number of game site users is equivalent to half of the K‐5 Internet population in the USA. However, there is little evidence that the math games on the website meet the criteria for effective instruction as described in the literature. This study found a significant negative correlation between search volumes for the game site in the 50 states in the USA and 4th grade students' performance in mathematics and reading. Moreover, Internet users in the states with greater numbers of low‐income families and fewer college graduates were more likely to search for the game site. The implications of these findings are discussed.
Characterization of squamous cell carcinomas of the head and neck using methods of spatial statistics
Authors: MATTFELDT T. , FLEISCHER F. 
Published: August 2014

SummaryIn the present study, 53 cases of squamous cell carcinomas of the head and neck were characterized by a quantitative histological texture analysis based on principles of spatial statistics. A planar tessellation of the epithelial tumour component was generated by a skeletonization algorithm. The size distribution of the virtual cells of this planar tessellation, and the size distribution of the profiles of the tumour cell nuclei were estimated in terms of area and boundary length. The intensity, the reduced second moment function (K‐function) and the pair correlation function of the point process of the centroids of the profiles of the tumour cell nuclei were also estimated. For both purposes, it is necessary to correct for edge effects, which we consider in this paper in some detail. Specifically, the point patterns of the tumour cell nuclei were considered as realizations of a point process, where the points exist only in the epithelial tumour component (the permitted phase) and not in the stroma (the forbidden phase). The methods allow to characterize each individual tumour by a series of summary statistics. The total set of cases was then partitioned into two groups: 19 cases without lymph node metastases (pN0), and 34 nodal positive cases (pN1 or pN2). Statistical analysis showed no significant differences between the intensities, the mean K‐functions and the mean pair correlation functions of the tumour cell nucleus profiles of the two groups. However, there were some significant differences between the sizes of the virtual cells and of the nucleus profiles of the nodal negative cases as compared to the nodal positive cases. In a logistic regression analysis, one of the quantitative nuclear size variables (mean nuclear area) was found to be a significant predictor of lymph node metastasis, in addition to tumour stage. The study shows the potential of methods of spatial statistics for objective quantitative grading of squamous cell carcinomas of the head and neck, and provides an example for modelling histological point patterns as realizations of planar point processes occupying a reference phase which is only a partial component of the total tissue.
Heterogeneity of shale documented by micro‐FTIR and image analysis
Authors: CHEN YANYAN , MASTALERZ MARIA , SCHIMMELMANN ARNDT 
Published: August 2014

SummaryIn this study, four New Albany Shale Devonian and Mississippian samples, with vitrinite reflectance [Ro] values ranging from 0.55% to 1.41%, were analyzed by micro‐FTIR mapping of chemical and mineralogical properties. One additional postmature shale sample from the Haynesville Shale (Kimmeridgian, Ro = 3.0%) was included to test the limitation of the method for more mature substrates. Relative abundances of organic matter and mineral groups (carbonates, quartz and clays) were mapped across selected microscale regions based on characteristic infrared peaks and demonstrated to be consistent with corresponding bulk compositional percentages. Mapped distributions of organic matter provide information on the organic matter abundance and the connectivity of organic matter within the overall shale matrix. The pervasive distribution of organic matter mapped in the New Albany Shale sample MM4 is in agreement with this shale's high total organic carbon abundance relative to other samples. Mapped interconnectivity of organic matter domains in New Albany Shale samples is excellent in two early mature shale samples having Ro values from 0.55% to 0.65%, then dramatically decreases in a late mature sample having an intermediate Ro of 1.15% and finally increases again in the postmature sample, which has a Ro of 1.41%. Swanson permeabilities, derived from independent mercury intrusion capillary pressure porosimetry measurements, follow the same trend among the four New Albany Shale samples, suggesting that micro‐FTIR, in combination with complementary porosimetric techniques, strengthens our understanding of porosity networks. In addition, image processing and analysis software (e.g. ImageJ) have the capability to quantify organic matter and total organic carbon – valuable parameters for highly mature rocks, because they cannot be analyzed by micro‐FTIR owing to the weakness of the aliphatic carbon–hydrogen signal.
Non‐surgical periodontal therapy with systemic antibiotics in patients with untreated chronic periodontitis: a systematic review and meta‐analysis
Authors: Keestra J. A. J. , Grosjean I. , Coucke W. , Quirynen M. , Teughels W. 
Published: August 2014

ObjectiveThe purpose of this meta‐analysis is to evaluate the effectiveness of different systemic antibiotics in combination with scaling and root planing (SRP) when compared to SRP alone in patients with untreated chronic periodontitis.BackgroundAlthough chronic periodontitis is mostly treated without adjunctive systemic antibiotics, some recent meta‐analyses have shown clinical benefit for some systemic antibiotics when used as an adjunct to SRP. However, there is a wide variety of systemic antibiotic regimens used today. It remains unclear if the selected type of systemic antibiotic influences the magnitude of clinical benefit.Material and MethodsThe MEDLINE‐PubMed database was searched from their earliest records through May 16, 2013. Several journals were hand searched and some authors were contacted for additional information. Outcome measures analysed were mean bleeding on probing change, mean clinical attachment level gain and mean probing pocket depth reduction. Extracted data were pooled using a random effect model. Weighted mean differences were calculated and heterogeneity was assessed.ResultsThe search yielded 281 abstracts. Ultimately, 95 studies were selected, describing 43 studies meeting the eligibility criteria. Systemic antibiotics showed a significant (p < 0.05) additional pocket depth reduction for moderate (at 3 mo 0.27 mm ± 0.09, at 6 mo 0.23 mm ± 0.10 and at 12 mo 0.25 mm ± 0.27) and deep pockets (at 3 mo 0.62 mm ± 0.17, at 6 mo 0.58 mm ± 0.16 and at 12 mo 0.74 mm ± 0.30). Statistically, no specific type of antibiotic was superior over another. However, when analysing the clinical data for initially moderate pockets or deep pockets, some trends became apparent.ConclusionSystemic antibiotics combined with SRP offer additional clinical improvements compared to SRP alone. Although there were no statistically significant differences, there was a trend that for initially moderate and deep pockets, metronidazole or metronidazole combined with amoxicillin, resulted in clinical improvements that were more pronounced over doxycycline or azithromycin. Additionally, there was a trend that the magnitude of the clinical benefit became smaller over time (1 year).
Effect of Calamondin Fiber on Rheological, Antioxidative and Sensory Properties of Dough and Steamed Bread
Authors: Fu Jhong‐Tai , Shiau Sy‐Yu , Chang Rei‐Chu 
Published: August 2014

AbstractCalamondin fiber (CF) was extracted and incorporated into dough and steamed bread. Results showed that the substitution of wheat flour by CF resulted in a stiffer and less extensible dough. Both Peleg–Normand and Wiechert models fitted well to the stress relaxation data of steamed bread. Hardness of steamed bread increased with the increase of CF substitution, but the cohesiveness, specific volume and elasticity decreased with the fiber substitution. As CF substitution was increased from 0 to 9%, total phenolic content and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical‐scavenging capacity of the steamed bread were improved by about 23 and 34, 52 and 53, as well as 77 and 74%, respectively. In sensory evaluation, steamed breads with 0–6% CF had similar flavor, texture and overall scores. These results suggest that the addition of 3 or 6% CF can produce healthy and acceptable fiber‐enriched steamed bread with higher phytochemicals and antioxidant capacity.Practical ApplicationsConsumption of dietary fiber offers health benefits including lower risk for many chronic diseases. The increased consumption of steamed bread enriched with calamondin fiber is proposed for health reasons. Calamondin is one of citrus fruits, and its pomace contains some phytochemicals, such as fiber, phenolics and flavonoids. The calamondin fiber was extracted and could be supplied as a potential source of dietary fiber. The study demonstrated that fiber‐enriched steamed bread with good sensory and nutritional quality could be produced by the partial substitution of wheat flour by calamondin fiber.
Effects of Maropitant Citrate or Acepromazine on the Incidence of Adverse Events Associated with Hydromorphone Premedication in Dogs
Authors: Claude A.K. , Dedeaux A. , Chiavaccini L. , Hinz S. 
Published: August 2014

BackgroundVomiting is a common complication associated with the use of hydromorphine for pre‐emptive analgesia in dogs. The ideal anti‐emetic protocol for prevention of this complication has not been established.HypothesisMaropitant administered concurrently or before hydromorphone would reduce the incidence of vomiting, signs of nausea, ptyalism, and increased panting compared to administration of acepromazine or a 0.9% saline control.AnimalsSixty mixed‐breed female dogs scheduled for ovariohysterectomy.MethodsRandomized, blinded, placebo‐controlled experimental study. Dogs were assigned to 4 experimental groups with 15 dogs per group. All groups received 0.2 mg/kg of hydromorphone IM. Group “Control” received 0.1 mL/kg saline SC 30–45 minutes before hydromorphone, group “Marop1” received 1 mg/kg maropitant SC 30–45 minutes before hydromorphone, group “Ace” received 0.02 mg/kg IM acepromazine 30–45 minutes before hydromorphone, and group “Marop2” received 1 mg/kg SC maropitant concurrently with hydromorphone. A trained and blinded observer documented adverse events from the time hydromorphone was administered until the time dogs were induced for surgery.ResultsMarop1 had significantly less vomiting (0%) compared to Control (87%; P < .01) and Ace (53%; P < .01). Marop2 had significantly less vomiting (27%) compared to Control (P < .01). Marop1 had significantly greater incidence of ptyalism (73%) compared to Ace (P < .01; 20%). Ace showed significantly less panting (33%) compared to Marop2 (93%; P < .01).Conclusions and Clinical ImportanceIn healthy dogs, maropitant citrate administered before hydromorphone significantly decreases the incidence of vomiting in dogs but does not improve signs of nausea, ptyalism, or increased panting.
The Meteoritical Bulletin, No. 100, 2014 June
Authors: Ruzicka Alex , Grossman Jeffrey N. , Garvie Laurence 
Published: August 2014

AbstractMeteoritical Bulletin 100 contains 1943 meteorites including 8 falls (Boumdeid [2011], Huaxi, Košice, Silistra, Sołtmany, Sutter's Mill, Thika, Tissint), with 1575 ordinary chondrites, 139 carbonaceous chondrites, 96 HED achondrites, 25 ureilites, 18 primitive achondrites, 17 iron meteorites, 15 enstatite chondrites, 11 lunar meteorites, 10 mesosiderites, 10 ungrouped achondrites, 8 pallasites, 8 Martian meteorites, 6 Rumuruti chondrites, 3 enstatite achondrites, and 2 angrites, and with 937 from Antarctica, 592 from Africa, 230 from Asia, 95 from South America, 44 from North America, 36 from Oceania, 6 from Europe, and 1 from an unknown location. This will be the last Bulletin published in the current format. Information about approved meteorites can be obtained from the Meteoritical Bulletin Database (MBD) available online at http://www.lpi.usra.edu/meteor/
Early and late response of Nematostella vectensis transcriptome to heavy metals
Authors: Elran Ron , Raam Maayan , Kraus Roey , Brekhman Vera , Sher Noa , Plaschkes Inbar , Chalifa‐Caspi Vered , Lotan Tamar 
Published: August 2014

AbstractEnvironmental contamination from heavy metals poses a global concern for the marine environment, as heavy metals are passed up the food chain and persist in the environment long after the pollution source is contained. Cnidarians play an important role in shaping marine ecosystems, but environmental pollution profoundly affects their vitality. Among the cnidarians, the sea anemone Nematostella vectensis is an advantageous model for addressing questions in molecular ecology and toxicology as it tolerates extreme environments and its genome has been published. Here, we employed a transcriptome‐wide RNA‐Seq approach to analyse N. vectensis molecular defence mechanisms against four heavy metals: Hg, Cu, Cd and Zn. Altogether, more than 4800 transcripts showed significant changes in gene expression. Hg had the greatest impact on up‐regulating transcripts, followed by Cu, Zn and Cd. We identified, for the first time in Cnidaria, co‐up‐regulation of immediate‐early transcription factors such as Egr1, AP1 and NF‐κB. Time‐course analysis of these genes revealed their early expression as rapidly as one hour after exposure to heavy metals, suggesting that they may complement or substitute for the roles of the metal‐mediating Mtf1 transcription factor. We further characterized the regulation of a large array of stress‐response gene families, including Hsp, ABC, CYP members and phytochelatin synthase, that may regulate synthesis of the metal‐binding phytochelatins instead of the metallothioneins that are absent from Cnidaria genome. This study provides mechanistic insight into heavy metal toxicity in N. vectensis and sheds light on ancestral stress adaptations.
Plasticity in ploidy underlies plant fitness compensation to herbivore damage
Authors: Scholes Daniel R. , Paige Ken N. 
Published: August 2014

AbstractHow plants mitigate damage by animal herbivores is a fundamental ecological and evolutionary question of plant–animal interactions. Some plants can increase their fitness when damaged in a phenomenon termed ‘overcompensation’. Despite overcompensation being observed in a variety of plant species, its mechanistic basis remains elusive. Recent research has shown that the Arabidopsis thaliana genotype Columbia‐4 employs endoreduplication, the replication of the genome without mitosis, following damage and that it overcompensates for seed yield. The related genotype Landsberg erecta, in contrast, does not increase its endoreduplication following damage and suffers reduced seed yield. While these results suggest that a plant's ability to plastically increase its ploidy during regrowth may promote its mitigation of damage, no studies have explicitly linked the endoreduplication genetic pathway to the regrowth and fitness of damaged plants. By comparing fitness and ploidy between undamaged and damaged plants of Columbia‐4, Landsberg erecta and their offspring, we provide evidence that endoreduplication is directly involved in compensatory performance. We then overexpressed an endoreduplication regulator and compared this mutant's endoreduplication and compensation with its background genotype Columbia‐0, an undercompensator. Enhancing Columbia‐0's ability to endoreduplicate during regrowth led to the complete mitigation of the otherwise detrimental effects of damage on its fitness. These results suggest that the ability of these plants to increase their ploidy via endoreduplication directly impacts their abilities to compensate for damage, providing a novel mechanism by which some plants can mitigate or even benefit from apical damage with potential across the wide range of plant taxa that endoreduplicate.
Rotigotine transdermal system: developing continuous dopaminergic delivery to treat Parkinson's disease and restless legs syndrome
Authors: Benitez Arturo , Edens Heather , Fishman Jesse , Moran Kimberly , Asgharnejad Mahnaz 
Published: August 2014

Rotigotine is a nonergoline dopamine receptor agonist with structural similarity to dopamine. Rotigotine binds to the D1 through D5 dopamine receptors, having several times more affinity than dopamine does to the D2 and D3 receptors. Although rotigotine was demonstrated to restore locomotor activity in animal models of Parkinson's disease (PD), the rapid metabolism of rotigotine limited the development of an orally administered formulation. Rotigotine's high lipid solubility and extended duration of action when applied to the skin in experimental models of PD suggested that rotigotine was a candidate for transdermal application. The constant transdermal delivery of rotigotine over 24 h is hypothesized to approximate continuous agonist–receptor stimulation, which conceptually more closely mimics physiologic striatal dopamine receptor function. Randomized clinical studies have demonstrated rotigotine's efficacy, safety, and tolerability in patients with early‐ and advanced‐stage PD, including improvements in motor symptoms and off‐time. Although the etiology is unknown, restless legs syndrome (RLS) is thought to involve dopaminergic dysregulation. Randomized clinical studies also have demonstrated the efficacy of rotigotine in improving the symptoms of moderate‐to‐severe primary RLS. This review examines rotigotine's developmental history for transdermal administration leading to its approval for the treatment of early‐ and advanced‐stage PD and moderate‐to‐severe primary RLS.
Regulation of competence and gene expression in Streptococcus mutans by the RcrR transcriptional regulator
Authors: Seaton K. , Ahn S.‐J. , Burne R.A. 
Published: August 2014

SummaryAn intimate linkage between the regulation of biofilm formation, stress tolerance and genetic competence exists in the dental caries pathogen Streptococcus mutans. The rcrRPQ genes encode ABC exporters (RcrPQ) and a MarR‐family transcriptional repressor of the rcr operon (RcrR) that play a dominant role in the regulation of the development of genetic competence and connect competence with stress tolerance and (p)ppGpp production in S. mutans. Here we identify the target for efficient RcrR binding in the rcr promoter region using purified recombinant RcrR (rRcrR) protein in electrophoretic mobility shift assays and show that DNA fragments carrying mutations in the binding region were not bound as efficiently by rRcrR in vitro. Mutations in the RcrR binding site impacted expression from the rcrR promoter in vivo and elicited changes in transformation efficiency, competence gene expression, and growth inhibition by competence‐stimulating peptide; even when the changes in rcrRPQ transcription were minor. An additional mechanistic linkage of RcrR with competence and (p)ppGpp metabolism was identified by showing that the rRcrR protein could bind to the promoter regions of comX, comYA and relP, although the binding was not as efficient as to the rcrRPQ promoter under the conditions tested. Hence, tightly controlled autogenous regulation of the rcrRPQ operon by RcrR binding to specific target sites is essential for cellular homeostasis, and RcrR contributes to the integration of genetic competence, (p)ppGpp metabolism, and acid and oxidative stress tolerance in S. mutans through both direct and indirect mechanisms.
Ligand binding and homology modelling of insect odorant‐binding proteins
Authors: Venthur Herbert , Mutis Ana , Zhou Jing‐Jiang , Quiroz Andrés 
Published: August 2014

AbstractThis review describes the main characteristics of odorant‐binding proteins (OBPs) for homology modelling and presents a summary of structure prediction studies on insect OBPs, along with the steps involved and some limitations and improvements. The technique involves a computing approach to model protein structures and is based on a comparison between a target (unknown structure) and one or more templates (experimentally determined structures). As targets for structure prediction, OBPs are considered to play a functional role for recognition, desorption, scavenging, protection and transportation of hydrophobic molecules (odourants) across an aqueous environment (lymph) to olfactory receptor neurones (ORNs) located in sensilla, the main olfactory units of insect antennae. Lepidopteran pheromone‐binding proteins, a subgroup of OBPs, are characterized by remarkable structural features, in which high sequence identities (approximately 30%) among these OBPs and a large number of available templates can facilitate the prediction of precise homology models. Approximately 30 studies have been performed on insect OBPs using homology modelling as a tool to predict their structures. Although some of the studies have assessed ligand‐binding affinity using structural information and biochemical measurements, few have performed docking and molecular dynamic (MD) simulations as a virtual method to predict best ligands. Docking and MD simulations are discussed in the context of discovery of novel semiochemicals (super‐ligands) using homology modelling to conceive further strategies in insect management.
Temperature and photoperiod affect stress resistance traits in Drosophila melanogaster
Authors: Bauerfeind Stephanie S. , Kellermann Vanessa , Moghadam Neda N. , Loeschcke Volker , Fischer Klaus 
Published: August 2014

AbstractThe long‐term survival of species and populations depends on their ability to adjust phenotypic values to environmental conditions. In particular, the capability of dealing with environmental stress to buffer detrimental effects on fitness is considered to be of pivotal importance. Resistance traits are readily modulated by a wide range of environmental factors. In the present study, Drosophila melanogaster Meigen is used to investigate plastic responses to temperature and photoperiod in stress resistance traits. The results reveal that stress resistance traits (cold, heat, starvation and desiccation resistance) are affected by the factors temperature and sex predominantly. Cooler temperatures compared with warmer temperatures increase cold tolerance, desiccation and starvation resistance, whereas they reduce heat tolerance. Except for heat resistance, females are more stress‐resistant than males. Stress resistance traits are also affected by photoperiod. Shorter photoperiods decrease cold tolerance, whereas longer photoperiods enhance desiccation resistance. Overall, thermal effects are pervasive throughout all measured resistance traits, whereas photoperiodic effects are of limited importance in the directly developing (i.e. nondiapausing) flies used here, suggesting that pronounced photoperiodic effects on stress resistance traits may be largely limited to, and triggered by, diapause‐inducing effects.