bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigating College and Graduate Students’ Multivariable Reasoning in Computational Modeling
Authors: WU HSIN‐KAI , WU PAI‐HSING , ZHANG WEN‐XIN , HSU YING‐SHAO 
Published: April 2013

ABSTRACTDrawing upon the literature in computational modeling, multivariable reasoning, and causal attribution, this study aims at characterizing multivariable reasoning practices in computational modeling and revealing the nature of understanding about multivariable causality. We recruited two freshmen, two sophomores, two juniors, two seniors, four master's students, and four PhD students in atmospheric sciences as participants. Participants’ reasoning practices and understanding of multivariable causality were examined using semistructured interviews and recordings of their computer activities. Analyses show that participants with high expertise tended to take a mechanism approach to predict and identify relationships, focused more on multivariable relationships, and purposefully selected and tested variables. The findings also indicate that understanding about multiple causality involved recognition and identification of the integration rules of multiple effects and the attributes of variables (e.g., interactive and reciprocal) and relationships (e.g., direction and feedback loop). Additionally, this study suggests an interaction between participants’ reasoning practices and their understanding of multivariable causality; participants’ understanding about the integration rules and the attributes could initiate reasoning practices, and by the enactment of practices, the rules and attributes were confirmed and examined. This study provides insight into the nature of multivariable reasoning and the design of computer‐based modeling tools. © 2013Wiley Periodicals, Inc. Sci Ed 97:337–366, 2013
Learning to Assess Science in Linguistically Diverse Classrooms: Tracking Growth in Secondary Science Preservice Teachers’ Assessment Expertise
Authors: LYON EDWARD G. 
Published: April 2013

ABSTRACTAlthough studies have documented teachers’ growth in assessing science resulting from professional development or science methods courses, little attention has been given to growth while being prepared to assess a linguistically diverse student population. In this study, the growth of 11 secondary science preservice teachers is documented by expanding the analytical lens—looking at not only how teachers understand and plan to use assessment formatively but also their consideration of assessment design and assessment equity for English learners. Drawing on interviews, open‐ended prompts, and program artifacts collected throughout the yearlong teacher education program, quantitative and qualitative findings indicate that the teachers demonstrated the most growth in their expertise at using assessment to support learning. Although quantitative analyses indicate that changes in the teachers’ expertise at designing assessment and considering equity in assessment were not statistically significant, additional analyses revealed nuanced ways in which the teachers’ expertise grew: expanding their repertoire of assessment tasks, considering alignment of assessment tasks with learning objectives, and becoming more knowledgeable of the role of language while assessing. I argue that broadening how we analyze assessment, combined with an expanded time frame, provides new information about the extent to which teachers are prepared to assess science in linguistically diverse classrooms. © 2013 Wiley Periodicals, Inc. Sci Ed 97:442–467, 2013
Server‐aided batch verification signature schemes in the multiple‐signer setting
Authors: Wang Bin , Zhao Qing 
Published: April 2013

ABSTRACTServer‐aided verification (SAV) signature schemes are useful for power‐constrained devices since a powerful server can assist in performing costly operations such as pairing operations. Wu et al. defined security notions for SAV signature schemes and constructed SAV protocols for some existing signature schemes. We extend their work by introducing a new notion called server‐aided batch verification (SABV) signature schemes, which allows signatures on (possibly) different messages by (possibly) different signers to be simultaneously verified with the help of an honest server. Then, we define completeness, soundness, and existential unforgeability for SABV signature schemes in the multiple‐signer setting. In the following, we design SABV protocols for Waters signature and Boneh–Lynn–Shacham signature, respectively, and prove that these protocols meet the requirement of soundness defined in this paper. Finally, we evaluate the performance of the proposed SABV protocols to show that the cost of a verifier can be further reduced compared with the corresponding SAV protocols presented by Wu et al. Copyright © 2013 John Wiley & Sons, Ltd.
Dual Growth Factor Delivery Using Biocompatible Core–Shell Microcapsules for Angiogenesis
Authors: Choi Dong Hoon , Subbiah Ramesh , Kim Ik Hwan , Han Dong Keun , Park Kwideok 
Published: April 2013

AbstractAn optimized electrodropping system produces homogeneous core–shell microcapsules (C‐S MCs) by using poly(L‐lactic‐co‐glycolic acid) (PLGA) and alginate. Fluorescence imaging clearly shows the C‐S domain in the MC. For release control, the use of high‐molecular‐weight PLGA (HMW 270 000) restrains the initial burst release of protein compared to that of low‐MW PLGA (LMW 40 000). Layer‐by‐layer (LBL) assembly of chitosan and alginate on MCs is also useful in controlling the release profile of biomolecules. LBL (7‐layer) treatment is effective in suppressing the initial burst release of protein compared to no LBL (0‐layer). The difference of cumulative albumin release between HMW (7‐layer LBL) and LMW (0‐layer LBL) PLGA is determined to be more than 40% on day 5. When dual angiogenic growth factors (GFs), such as platelet‐derived GF (PDGF) and vascular endothelial GF (VEGF), are encapsulated separately in the core and shell domains, respectively, the VEGF release rate is much greater than that of PDGF, and the difference of the cumulative release percentage between the two GFs is about 30% on day 7 with LMW core PLGA and more than 45% with HMW core PLGA. As for the angiogenic potential of MC GFs with human umbilical vein endothelial cells (HUVECs), the fluorescence signal of CD31+ suggests that the angiogenic sprout of ECs is more active in MC‐mediated GF delivery than conventional GF delivery, and this difference is significant, based on the number of capillary branches in the unit area. This study demonstrates that the fabrication of biocompatible C‐S MCs is possible, and that the release control of biomolecules is adjustable. Furthermore, MC‐mediated GFs remain in an active form and can upregulate the angiogenic activity of ECs.
Relationships, learning, and development: A student perspective
Authors: Bernstein‐Yamashiro Beth , Noam Gil G. 
Published: April 2013

AbstractIn data derived from student interviews, students describe how they see teacher‐student relationships function for them in their experience of school, their personal development, and their academic success. These relationships are central to students' ability to feel connected at school and to their emerging identities. Students describe how certain teachers are able to reach out to them personally, enabling them to access curriculum and build a positive personal mentoring connection to an adult. Students also explain how being able to rely on relationships with their teachers helps them cope with the many emotional challenges they face as adolescents.
Establishing and maintaining boundaries in teacher‐student relationships
Authors: Bernstein‐Yamashiro Beth , Noam Gil G. 
Published: April 2013

AbstractBecause schools rarely provide guidelines for teachers that outline how they should conduct personal relationships with students, teachers must wrestle individually with how to establish, communicate, and maintain clear boundaries in their interactions. As schools work to become more personal environments, school administrators will need to help teachers understand their roles as close advisors and mentors to students, while drawing and maintaining clear and obvious boundaries within these relationships. Students have clear ideas on how they prefer their teachers to interact with them and what feels comfortable in these relationships. Teachers also discuss from experience how they have managed to find comfortable ways to delimit relationships and continue to be effective mentors for students.
A Process Model for Approximating the Production Costs of the Fermentative Synthesis of Sophorolipids
Authors: Ashby Richard D. , McAloon Andrew J. , Solaiman Daniel K. Y. , Yee Winnie C. , Reed Marshall 
Published: April 2013

AbstractSophorolipids are microbial glycolipids that possess surfactant‐type properties. Sophorolipids have been tested successfully in a number of potential industrial and niche applications but are generally acknowledged to require higher production costs when compared to petroleum‐based surfactants. The objective of this study was to develop a process economic model for the fermentative synthesis of sophorolipids using contemporary process simulation software and current reagent, equipment, and supply costs, following current production practices. Glucose (Glc) and either high oleic sunflower oil (HOSO) or oleic acid (OA) were used as feedstocks and the annual production capacity of the plant was set at 90.7 million kg/year with continuous operation of 24 h a day for 330 days per year. Major equipment costs were calculated to be US$17.1 million but other considerations such as capital, labor, material and utilities costs were also included. The single greatest contributor to the overall production/operating cost was raw materials, which accounted for 89 and 87 % of the total estimated production expenditures for the HOSO and OA‐based fermentations, respectively. Based on this model and yields of 100 g/L, the cost of large‐scale sophorolipid synthesis via fermentation from Glc:HOSO was calculated to be US$2.95/kg ($1.34/lb) and from Glc:OA to be US$2.54/kg ($1.15/lb). The model is flexible and can be adjusted to reflect changes in capital, production and feedstock costs as well as changes in the type of feedstocks used.
Synthesis and Characterization of Acetylated and Stearylyzed Soy Wax
Authors: Yao Linxing , Lio JunYi , Wang Tong , Jarboe Darren H. 
Published: April 2013

AbstractA solvent‐free synthesis method was developed for incorporating acetyl and hydroxy groups and long‐chain fatty alcohol in fully hydrogenated soybean oil (FHSO) to produce a wax to be used as beeswax or paraffin substitutes in packaging and coatings. FHSO was reacted with stearyl alcohol and triacetin at 140–150 °C for 2 h, and the reaction was catalyzed by 0.018 wt% sodium methoxide. The addition of alcohol increased the reaction yield and the melting point of the final wax by 9 and 25 %, respectively, compared to the wax produced from the reaction of FHSO and triacetin alone. The effects of the ratio of stearyl alcohol and triacetin to FHSO on the textural properties of the modified soy wax were examined. The reaction of FHSO:stearyl alcohol:triacetin at a molar ratio of 9:7:15 produced a wax that was 1.2 and 2.4 times harder than beeswax and FHSO, respectively, but 1.7 times softer than a commercial grade paraffin wax. This modified soy wax comprised 75 % acetylated glycerol esters including diacetylmonoacylglycerides (31 %), monoacetylmono‐ (12 %) and diacylglycerides (32 %), and 25 % non‐acetylated molecules including wax ester (14 %), and acylglycerides (11 %). The acetylated soy wax had high cohesiveness and did not break under compression.
Effect of glucocorticoids on nasal polyposis, with detection of inflammatory response by measurement of nitric oxide levels in nasal polyp tissue
Authors: Bülbül T , Bülbül Ö Gümüştekin , Güçlü O , Bilsel A Serpil , Gürsan S Önal 
Published: April 2013

AbstractObjective:To investigate endoscopic staging, and nitric oxide levels in the polyp tissue, in patients with nasal polyposis undergoing glucocorticoid therapy.Methods:Nasal polyposis was evaluated using endoscopic staging and measurement of polyp tissue nitric oxide levels (chemiluminescence method). Forty-five nasal polyposis patients received either nasal therapy (n = 15), oral therapy (n = 15) or combined therapy (n = 15). Pre-treatment and post-treatment staging and nitric oxide levels were evaluated.Results:Endoscopic grading indicated significant post-treatment staging improvements in the oral (p = 0.016) and combined (p = 0.016) groups. Post-treatment staging differed significantly between the three groups (p = 0.041), with greater improvements in the oral and combined groups. All groups showed significantly lower post-treatment nitric oxide levels, compared with baseline, but post-treatment levels did not differ significantly between groups. A significant association was found between treatment response and nitric oxide level alteration.Conclusion:This study demonstrates the favourable effects of glucocorticoids on nasal polyposis, and alteration in nitric oxide tissue levels post-treatment. Nitric oxide level in nasal polyp tissue could be an indicator of treatment response, and may aid surgical decision-making by detecting cases that probably will not respond to medical treatment.
Lateral undulation of snake robots: a simplified model and fundamental properties
Authors: Liljebäck Pål , Pettersen Kristin Y. , Stavdahl Øyvind , Gravdahl Jan Tommy 
Published: April 2013

SUMMARYThis paper considers the lateral undulation motion of snake robots. The first contribution of the paper is a model of lateral undulation dynamics developed for control design and stability analysis purposes. The second contribution is an analysis of the simplified model that shows that any asymptotically stabilizing control law for the snake robot to an equilibrium point must be time varying. Furthermore, the analysis shows that a snake robot (with four links) is strongly accessible from almost any equilibrium point, except for certain singular configurations, and that the robot does not satisfy sufficient conditions for small-time local controllability. The third contribution is based on using averaging theory to prove that the average velocity of the robot during lateral undulation will converge exponentially fast to a steady-state velocity which is given analytically as a function of the gait pattern parameters. From the averaging analysis, we also derive a set of fundamental relationships between the gait parameters of lateral undulation and the resulting forward velocity of the snake robot. The paper presents simulation results and results from experiments with a physical snake robot that support the theoretical findings.
QUALITY INDICATORS TO ASSESS A COLORECTAL CANCER PREVENTION PROGRAM
Authors: Serra-Sutton Victoria , Serrano Carmela Barrantes , Carreras Mireia Espallargues 
Published: April 2013

Objectives: The aim of this study was to implement a set of indicators to assess the quality of care of a new healthcare model for prevention of colorectal cancer in a high-risk population.Methods: Information was obtained retrospectively from electronic clinical records, review of documentation, and a survey. The high-risk clinic for colorectal cancer was created in Barcelona (Spain) in 2006. All users at greater risk of colorectal cancer assessed through the new healthcare model were included. Twenty-one indicators were computed using defined formulas and standards. Logistic regression models were computed to analyze factors related to adherence to the screening and surveillance prevention strategies.Results: A total of 1,275 users were included. Eight of seventeen indicators reached the quality standard (80 percent structure, 50 percent process, and 17 percent outcome), whereas four indicators did not have a previously defined standard. The overall adherence to the screening and surveillance program was 67 percent. Users aged 59 and older had almost two times greater probabiblity (95 percent confidence interval [CI], 1.3–3.1) of adherence than younger users; users with surveillance colonoscopies presented a 7.4 times (95 percent CI, 4.6–11.7) greater probability of adherence than those with screening colonoscopies.Conclusions: The indicators have been shown to be feasible and valid tools to identify areas of improvement in this new model, such as information systems, continuity of care, and communication among professionals. Because this was the first time these indicators were applied to assess the high-risk clinic for colorectal cancer, further implementation is required to improve the interpretability of results.
From strategic ambiguity to technical reference points in the Antarctic krill fishery: the worst journey in the world?
Authors: HILL SIMEON L. 
Published: April 2013

SUMMARYThe goals of ecosystem based management (EBM) are strategically ambiguous, meaning that they require interpretation to identify objectives for ecosystem state. Ecosystem states that are useful for achieving such objectives are known as reference points. Soft reference points specify both a state and a probability of the ecosystem being in that state. They are used with simulation models to identify management measures for which the risk of the ecosystem entering an undesirable state is below a specified level. The Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) is responsible for the EBM of Antarctic krill fisheries. CCAMLR used soft reference points for the krill stock in the Scotia Sea and southern Drake Passage to set a regional catch limit. However, this catch limit needs spatial subdivision to protect predators from localized depletion. Model-based evaluations of different options for subdividing the catch limit used illustrative reference points to assess the depletion risk to multiple predators. This study demonstrates that the apparent risk is sensitive to the choice of reference point and method for aggregating modelled predators. EBM practitioners and stakeholders need to be aware that these factors could therefore bias comparisons of management measures. Nonetheless, qualitative distinctions between different spatial subdivision options are relatively consistent except at high levels of aggregation and extreme reference points. This study also demonstrates a lack of generality in the relationship between current and future ecosystem state. Thus, the EBM goal of maintaining ecosystem resilience implies different reference points for the current state of different ecosystem components. Despite early progress in defining soft reference points for the krill stock, CCAMLR has not yet defined reference points for krill predators. Structured dialogue aimed at identifying collective objectives might be necessary to achieve further progress in CCAMLR and other EBM organizations.
A review of bovine tuberculosis at the wildlife–livestock–human interface in sub-Saharan Africa
Authors: De GARINE-WICHATITSKY M. , CARON A. , KOCK R. , TSCHOPP R. , MUNYEME M. , HOFMEYR M. , MICHEL A. 
Published: April 2013

SUMMARYInfection of wild animals by bovine tuberculosis (bTB) is raising concern worldwide. This article reviews the current epidemiological situation, risk of emergence and control options at the wildlife–livestock–human interface in sub-Saharan Africa. In livestock, bTB has been confirmed in the majority of countries from all parts of the continent. Wildlife infection is confirmed in seven countries from southern and eastern Africa, apparently spreading in the southern Africa region.Mycobacterium bovishas been isolated from 17 wild mammal species, although only four are suspected to play a role as maintenance host. Zoonotic risks are a concern, but no direct spillover from wildlife to humans has been documented, and no case of bTB spillback from wildlife to livestock has been confirmed. In this paper we assess the main risk factors of bTB spillover at the wildlife–livestock–human interface and suggest several research themes which could improve the control of the disease in the African context.
Seroepidemiology ofToxoplasma gondiiinfection in the Israeli population
Authors: MARKOVICH M. PERRY , SHOHAT T. , RIKLIS I. , AVNI R. , YUJELEVSKI-ROZENBLIT D. , BASSAL R. , COHEN D. , RORMAN E. 
Published: April 2013

SUMMARYToxoplasmosis seroprevalence varies considerably between countries. We studied the seoprevalence ofToxoplasma gondiiIgG antibodies in a national sample of the Israeli population; 2794 sera were tested. The highest age-adjusted seroprevalence rate was in Arabs (non-Bedouins) (60·4%), significantly higher compared to the rate in Jews (19·9%) and Bedouins (27·5%) (P < 0·01). There were no significant gender differences. Seropositivity increased with age in all population groups. For Jews, seropositivity was associated with place of birth and socioeconomic status. A finding of low seroprevalence rate in Bedouins despite their poor living conditions and close contact with livestock is surprising, and might be attributed to the dry and hot climate conditions in their area of residence. In women of reproductive age the seroprevalence was 15·1% in Jews, 25·4% in Bedouins and 72·3% in Arabs (non-Bedouins). Thus, the majority of pregnant women are susceptible to primary infection withT. gondii, and the risk for congenital toxoplasmosis remains high.
Enhanced tunable performance of high Q-factor BaxSr1−xTiO3 film bulk acoustic wave resonators
Authors: Vorobiev Andrei , Gevorgian Spartak 
Published: April 2013

Emerging intrinsically tunable film bulk acoustic wave(BAW) resonators allow the development of new generation reconfigurable and agile microwave circuits. In this paper, we demonstrate the enhancement of tunable performance of the high Q-factor BaxSr1−xTiO3 BAW – solidly mounted resonators (BAW–SMR) by varying Ba concentration. The Ba0.5Sr0.5TiO3 BAW–SMR reveal tunability of series resonance frequency up to 2.4%, electromechanical coupling coefficient up to 7.5% and rather high Q-factor, up to 250 at 5.3 GHz. Correlations between the measured electroacoustic parameters are analyzed using the theory of dc field-induced piezoelectric effect in paraelectric phase ferroelectrics. Higher coupling coefficient and tunability of resonance frequency of the Ba0.5Sr0.5TiO3 BAW–SMR are associated with higher tunability of permittivity. Strong anisotropy in field-induced piezoelectric effect is predicted with highest coupling coefficient in (001) direction of the BaxSr1−xTiO3 films. It is also shown that the tunability of series resonance frequency of Ba0.5Sr0.5TiO3 BAW–SMR is limited by relatively high and negative nonlinear electrostriction coefficient which is found to be m ≈ −4·1010 m/F. The BAW–SMR Q-factor is limited significantly by extrinsic acoustic loss associated with wave scattering at reflection from relatively rough top interface. The results of analysis show possible ways of further improvement of the performance of tunable BAW–SMR.