bluuebunny/crossref_metadata_2025 huggingface dataset:
Diffusion tensor magnetic resonance imaging in very early onset pediatric multiple sclerosis
Authors: Rocca MA , Sonkin M , Copetti M , Pagani E , Arnold DL , Narayanan S , Sled JG , Banwell B , Filippi M
Published: July 2015

Objectives:

Active myelination during childhood may influence the impact of multiple sclerosis (MS) on brain structural integrity. We studied normal-appearing white matter (NAWM) in children with MS onset before age 12 years using diffusion tensor (DT) magnetic resonance imaging (MRI).

Methods:

DT MRI scans were obtained from 22 MS children with their first attack before age 12 years, and 31 healthy controls from two referral centers. Using probabilistic tractography, brain tissue integrity within interhemispheric, intrahemispheric, and projection tracts was compared between patients and site-matched controls. The impact of disease and age at MRI on tract NAWM fractional anisotropy (FA) and mean diffusivity (MD) values was evaluated using linear models.

Results:

Compared to controls, pediatric MS patients had reduced FA and increased MD of the bilateral superior longitudinal fasciculus and corpus callosum (CC), without center-by-group interaction. CC NAWM average FA was correlated with brain T2 lesion volume. In controls, the majority of the tracts analyzed showed a significant increase of FA and decrease of MD with age. Such a linear correlation was lost in patients.

Conclusions:

In very young pediatric MS patients, DT MRI abnormalities affect brain WM tracts differentially, and are only partially correlated with focal WM lesions. Impaired maturation of WM tracts with age may be an additional factor contributing to these findings.
Fatal toxic epidermal necrolysis in a patient on teriflunomide treatment for relapsing multiple sclerosis
Authors: Gerschenfeld Gaspard , Servy Amandine , Valeyrie-Allanore Laurence , de Prost Nicolas , Cecchini Jérôme
Published: July 2015

We report a case of toxic epidermal necrolysis in a 46-year-old woman on teriflunomide treatment. Such a severe adverse cutaneous drug reaction with this new therapy for relapsing forms of multiple sclerosis should be early recognized in order to ensure the rapid withdrawal of the drug.
Open economy politics and international security dynamics: Explaining international cooperation in financial crises
Authors: Walter Andrew
Published: July 2015

Why do states cooperate during international financial crises? A prominent account of such phenomena is provided by the Open Economy Politics approach, which advocates a methodological reductionism that focuses on domestic interests and institutions as explanatory drivers of foreign economic policy. I argue that the appropriateness and utility of this approach diminishes in two important contexts: when levels of economic interdependence and international institutionalization are both high; and when international insecurity is rising. Since the second condition has greater generality in international relations, I test it by focusing on a period when international economic institutionalization was much lower than today: the pre-1914 gold standard system. I show that as levels of interstate rivalry and insecurity rose in the years before 1914, so too did the role of strategic considerations in the international financial policies of the major European powers. The utility of the Open Economy Politics approach for explaining foreign financial policy is therefore contingent on an evolving international context. The argument is of considerable relevance to the contemporary era, when a rapidly evolving international political environment is again reshaping international financial policies.
Educational change leadership through a new zonal theory lens: Using mathematics curriculum change as the example
Authors: Lamb Janeen , Branson Christopher M
Published: July 2015

This paper outlines actions that educational change leaders can take to better meet their curriculum change obligations and responsibilities. In order to do this we extend Vygotsky’s (1978) zonal theory and its many extensions and elaborations by positioning educational change leadership within this theory. We rename the zones to Zone of Principal Responsibilities, Zone of Principal Support, Zone of Professional Learning, Zone of Teacher Resistance and Zone of Principal Illusion, and we introduce the Zone of Curriculum Change and represent these zones in diagrammatical form. We use our research on mathematics curriculum change in one school as an example of how our new zonal theory lens supports educational change leadership. Our findings illuminate possible actions and reactions of the principal and the teacher that ultimately suggest a way forward for turning around unsuccessful curriculum change. Our new zonal theory provides opportunities for change leaders to reduce teacher resistance with evidence that the action and reaction of the principal and the teacher are not independent of each other but are, in fact, co-constructed.
Vertical Diffusion and the Shifting Politics of Electronic Commerce
Authors: Karch Andrew , Rosenthal Aaron
Published: July 2015

Since the late 1990s, Congress and the states have debated how to treat electronic commerce for purposes of sales taxation. Frustrated by their limited progress at the national level, advocates of policy change attempted to generate vertical diffusion by using increasingly aggressive state-level actions to press Congress to act. The state initiatives provided national legislators with an “opportunity to learn,” and a systematic analysis of congressional policymaking suggests that vertical diffusion affected the early stages of the legislative process. State policies influenced the specific options that national officials considered, the rhetoric they employed, and, less consistently, bill cosponsorship patterns. The impact of vertical diffusion receded, however, as the congressional debate continued. Its muted effect during the later stages of the legislative process implies that national officials do not necessarily learn from what occurs in the “laboratories of democracy.” In addition to shedding light on the shifting politics of electronic commerce, this study illustrates the benefits both of studying the impact of vertical diffusion on individual decision-making and of conceptualizing vertical diffusion as a process rather than as an outcome to be explained.
The Social Network Gamer’s Experience of Play
Authors: García-Álvarez Ercilia , López-Sintas Jordi , Samper-Martínez Alexandra
Published: July 2015

We address the subjective experience of social network gamers playing Restaurant City, a game hosted on Facebook. We adopted a netnographic approach to studying the culture of transient Internet communities shaping the player off-line communities. Fieldwork was conducted over the entire life span of the game (3 years). Data were analyzed using a qualitative thematic approach and the software EdEt. The results describe the evolution of the gaming experience through online interaction and its importance in everyday off-line life. Players were observed to play an important role in the production of social meanings associated with gaming and with the gaming community online and off-line. We discuss the implications of our findings regarding how the gaming process is a far more complex scenario than envisaged by a business vision based on acquisition, retention, and monetization.
Longitudinal Study of Body Mass Index in Young Males and the Transition to Fatherhood
Authors: Garfield Craig F. , Duncan Greg , Gutina Anna , Rutsohn Joshua , McDade Thomas W. , Adam Emma K. , Coley Rebekah Levine , Chase-Lansdale P. Lindsay
Published: July 2015

Despite a growing understanding that the social determinants of health have an impact on body mass index (BMI), the role of fatherhood on young men’s BMI is understudied. This longitudinal study examines BMI in young men over time as they transition from adolescence into fatherhood in a nationally representative sample. Data from all four waves of the National Longitudinal Study of Adolescent Health supported a 20-year longitudinal analysis of 10,253 men beginning in 1994. A “fatherhood-year” data set was created and changes in BMI were examined based on fatherhood status (nonfather, nonresident father, resident father), fatherhood years, and covariates. Though age is positively associated with BMI over all years for all men, comparing nonresident and resident fathers with nonfathers reveals different trajectories based on fatherhood status. Entrance into fatherhood is associated with an increase in BMI trajectory for both nonresident and resident fathers, while nonfathers exhibit a decrease over the same period. In this longitudinal, population-based study, fatherhood and residence status play a role in men’s BMI. Designing obesity prevention interventions for young men that begin in adolescence and carry through young adulthood should target the distinctive needs of these populations, potentially improving their health outcomes.
Trajectory tracking control of an underactuated unmanned underwater vehicle synchronously following mother submarine without velocity measurement
Authors: Xu Jian , Wang Man , Zhang Gengshi
Published: July 2015

This article addresses the trajectory tracking control of underactuated unmanned underwater vehicles, where the control structure is designed to synchronously follow the mother submarine with only available position information. The controller is derived using the virtual guidance strategy and backstepping-based design techniques. The virtual guidance system is first constructed to eliminate the measurement of the mother submarine’s velocity and dynamics. The convergence and effectiveness of the virtual guidance system are proven using Lyapunov stability theory. In addition, to enhance the robustness of the underactuated vehicle against the unmodeled dynamics and unknown disturbances from the environment, radial basis function neural networks are finally used to approximate the nonlinear uncertainties. Under the proposed control, semiglobal uniform boundedness of the closed-loop system is guaranteed for adequate choices of the controller gains. A simulation example is included to demonstrate the effectiveness and robustness of the approaches suggested.
Characterization of the nanoscratch, microstructure, and composition in hypoplastic amelogenesis imperfecta
Authors: Qing Ping , Li Yue , Gao Shanshan , Qiao Mengting , Qian Linmao , Yu Haiyang
Published: July 2015

Hypoplastic amelogenesis imperfecta is a widespread hereditary disease that causes the loss of enamel. The purpose of this study was to investigate the nanoscratch resistance of hypoplastic amelogenesis imperfecta for providing a reference for restorative treatment. Four unerupted third molars from a patient diagnosed with hypoplastic amelogenesis imperfecta and seven unerupted third molars from normal individuals were compared. Atomic force microscopy and energy-dispersive X-ray spectroscopy were used to observe the microstructure and composition of the teeth (enamel and dentin). The nanoscratch tests of teeth (enamel and dentin) were investigated using a nanoscratch tester, scanning electron microscopy, and a stylus profilometer. The results indicated that hypoplastic amelogenesis imperfecta teeth had different microstructures compared to normal teeth. Hypoplastic amelogenesis imperfecta demonstrated a higher composition of organic substance. Meanwhile, the friction coefficient of hypoplastic amelogenesis imperfecta was higher than that of normal teeth, and inferior frictional resistance of hypoplastic amelogenesis imperfecta teeth was observed. The main damaging mechanisms observed in hypoplastic amelogenesis imperfecta under nanoscratch were the combination of delamination, debris, and cracks in enamel with delamination, debris, and plastic deformation in dentin. Our findings suggested that new dental restorative materials should be selected to match the mechanical properties of hypoplastic amelogenesis imperfecta.
Cartoon Vision: UPA, Precisionism and American Modernism
Authors: Bashara Dan
Published: July 2015

Postwar animation studio United Productions of America (UPA) is credited with bringing a modern art sensibility to the American cartoon, a simplified, abstract style that transformed the look of studio animation throughout the 1950s and 1960s. This article examines UPA’s signature style alongside that of Precisionism, a little-discussed school of modernist American painting peaking in the 1920s. In so doing, it complicates our understanding of UPA’s relationship to modern art, and to modernism more broadly. Precisionism sought to bring order to a chaotic modern environment by reducing the visible world to a semi-abstract form in which urban and industrial scenes are built from geometric shapes, hard-edged lines, and solid color fields – precisely the traits defining UPA’s style. Through an analysis of the animation studio’s cartoons in the context of its beginnings in wartime training films, and of the written statements of its artists, this article positions UPA as a resurgence of the particular modernist energy driving Precisionism’s visual style: a theoretically engaged attempt to develop a new mode of vision capable of navigating the sensory overwhelm of modern life. It thus draws a line between these two periods in American cultural history, enabling a clearer understanding of mid-century modernism as a cultural phenomenon, and of postwar animation’s place within a decades-long current of modernist experiment.
Puppet Animation Films and Gesture Aesthetics
Authors: Mohamed Fauzi Naeim , Mohd Nor Nurul Lina
Published: July 2015

Gestures are meaningful acts of being. All gesture speaks of the formation of posture, and by this posture we can even comprehend the culture that is bound and produced in the action of gesture. This article examines the aesthetics of gesture found in puppet animation. Puppets are rich in their textured and sculptural forms and yet they have limited, wooden-like performance. However, it is their limitations – unlike smooth computer-generated imagery (CGI) or 2D animated drawings – which make every nuance in their performances exceptionally important and instructive in understanding the character’s motivation. Three short animation films – Jiří Trnka’s The Hand (1965), Kihachirō Kawamoto’s The Demon (1972) and Suzie Templeton’s Dog (2001) – are chosen as the case studies in this article. The authors elaborate on the way gestures are communicated through poses, shots and framings to then construct and discuss categories of gesture.
Music Video’s Performing Bodies: Floria Sigismondi as Gestural Animator and Puppeteer
Authors: Perrott Lisa
Published: July 2015

Auteur music video director Floria Sigismondi has a reputation for creating beautifully macabre imagery that has been described as surreal and uncanny. Less obvious is the way in which she uses animation and gesture to estrange the movement of performing bodies. While pixilation and stop motion animation are used together to invert the agency of humans and objects, Sigismondi’s use of gesture extends this manipulation of agency beyond technical processes. This dialectic of cinematic agency is discussed through an examination of three music videos directed by Sigismondi: End of the World (2004) for The Cure, Montauk Fling (2013) for Lawrence Rothman and The Stars (Are Out Tonight) (2013) for David Bowie. Considering these videos in relation to puppet animation, live-action film and the cultural and historical migration of gesture, the author argues that Sigismondi puppetises humans and animates gesture as a means of transgression.
Acute breathlessness
Authors: Davis Tim
Published: July 2015

Acute breathlessness is a common presentation to primary care; it can range from asthma exacerbations to congestive cardiac failure. Being able to assess and manage acute breathlessness is an important skill within general practice. This article covers the general principles of first-line assessment and the management of breathlessness in primary care, focusing on respiratory causes. Specific causes of breathlessness are covered with cases to highlight key learning points.
The effect of angiotensin II receptor blockers on hyperuricemia
Authors: Wolff Marissa L. , Cruz Jennifer L. , Vanderman Adam J. , Brown Jamie N.
Published: July 2015

The objective of this review was to explore the efficacy of angiotensin II receptor blockers (ARBs) for the treatment of hyperuricemia in individuals diagnosed with gout or hyperuricemia defined as ⩾7 mg/dl at baseline. A literature search of MEDLINE (1946 to June 2015) and EMBASE (1947 to June 2015) was conducted. The following search terms were used: ‘uric acid’, ‘urate transporter’, ‘gout’, ‘angiotensin II receptor blockers’, ‘hyperuricemia’ and the names for individual ARBs, as well as any combinations of these terms. Studies were excluded that did not explore fractional excretion or serum uric acid as an endpoint, if patients did not have a diagnosis of gout or hyperuricemia at baseline, or if they were non-English language. A total of eight studies met the inclusion criteria. Of the eight studies identified, six explored ARB monotherapy and two studies investigated ARBs as adjunct therapy. Losartan demonstrated statistically significant reductions in serum uric acid levels or increases in fractional excretion of uric acid in all studies, whereas no other ARB reached statistical benefit. The effect of ARBs on the occurrence of gout attacks or other clinical outcomes were not represented. Four studies evaluated safety effects of these agents indicating abnormalities such as minor changes in lab values. In conclusion, losartan is the only ARB that has consistently demonstrated a significant reduction in serum uric acid levels, although the significance of impacting clinical outcomes remains unknown. Losartan appears to be a safe and efficacious agent to lower serum uric acid levels in patients with hyperuricemia.
Endocrinological and biochemical changes of scorpionism in children in Upper Egypt
Authors: Ahmed Ahmed E. , Abdel-Baseer Khaled A. , Saad Khaled , Hassan Asmaa F. , El-Houfey Amira A.
Published: July 2015

Aim:

The aim of this study was to determine some endocrinological and biochemical changes of scorpionism in children in Upper Egypt. In addition, it aimed to find any possible relationship between these changes and the severity of scorpionism.

Patients and methods:

The present study was carried out at two university hospitals in Upper Egypt and included 42 children with envenomation and 20 apparently healthy children as controls. In all subjects, levels were measured of noradrenaline, aldosterone, insulin and cortisol, and some biochemical parameters and electrolytes including nitric oxide (NO), creatine phosphokinase (CPK), Na+ and K+.

Results:

Na+, NO and CPK levels were significantly higher in children with envenomation compared with the controls. Also, there was a significant reduction in K+ in patients compared with controls. Children with severe envenomation had significantly higher levels of noradrenaline, cortisol and aldosterone compared with the controls and mild cases. However, insulin levels were significantly decreased in severe cases of scorpionism compared with mild ones. Moreover, hyperglycemia was detected in all patients with envenomation compared with controls, with significantly higher blood glucose levels among children with severe envenomation compared with mild cases.

Conclusion:

Endocrinological changes were common in all children with scorpion envenomation and more obvious in cases of severe envenomation. The released mediators may account for several inflammatory manifestations such as pulmonary edema, myocardial failure, systemic inflammatory response syndrome and multiple organ failure. The use of insulin is recommended in cases of severe envenomation to improve the outcome.
Effect of balance training with Biodex Stability System on balance in diabetic neuropathy
Authors: Eftekhar-Sadat Bina , Azizi Roghayyeh , Aliasgharzadeh Akbar , Toopchizadeh Vahideh , Ghojazadeh Morteza
Published: July 2015

Objectives:

Diabetic neuropathy (DN) in the elderly is a common complication of diabetes that can negatively influence balance control. In this study, we aimed to evaluate the efficacy of balance training program on postural stability of diabetic patients.

Patients and methods:

In this randomized clinical trial, 34 elderly DN patients were divided into intervention ( n = 17) and control ( n = 17) groups. The experimental group underwent a balance training program using the Biodex Balance System (BBS) for 10 sessions. All subjects in both groups were assessed using timed ‘up and go’ (TUG) test, the Berg balance scale, and the fall risk and postural stability tests, at baseline and at the end of the study.

Results:

TUG ( p = 0.01), fall risk index ( p = 0.002), anterior/posterior index ( p = 0.01), medial/lateral index ( p = 0.04), overall stability index ( p = 0.01) and Berg balance scale ( p = 0.04) were significantly improved after the training in the intervention group, but had no significant differences in the control group. The changes in TUG ( p < 0.001) and fall risk index ( p < 0.001) in the intervention group were significantly higher than those in the control group.

Conclusion:

According to our results, balance training would improve postural stability and balance in elderly patients with DN.
Patient preference and tolerability of a DPP-4 inhibitor versus a GLP-1 analog in patients with type 2 diabetes mellitus inadequately controlled with metformin: a 24-week, randomized, multicenter, crossover study
Authors: Lüdemann Jörg , Dütting Eva D. , Dworak Markus
Published: July 2015

Objective:

The present study aimed to assess the patient preference and tolerability of oral dipeptidyl peptidase-4 inhibitor (vildagliptin) versus injectable glucagon-like peptide-1 analog (liraglutide) in patients with type 2 diabetes mellitus inadequately controlled with metformin monotherapy.

Methods:

This 24-week, randomized, multicenter, crossover study, patients with type 2 diabetes mellitus inadequately controlled on metformin monotherapy with hemoglobin A1c (HbA1c) ⩾6.5% and ⩽9.0% were randomized in a crossover manner to receive either vildagliptin/metformin single-pill combination (SPC) 50/1000 mg twice daily ( n = 32) or 1.2 mg liraglutide as an add-on to metformin (0.6 mg [weeks 0–1] followed by 1.2 mg [weeks 2–12] once daily/1000 mg twice daily) ( n = 30) for the first 12 weeks.

Results:

Patient preference at week 24 was similar, with 51.7% ( n = 31) patients preferring vildagliptin/metformin SPC compared with 48.3% ( n = 29) preferring liraglutide as an add-on to metformin therapy ( p = 0.449). Post hoc analyses showed that more elderly patients (⩾65 years) preferred vildagliptin (65%; n = 13) over liraglutide (35%; n = 7) therapy. Liraglutide was associated with better improvement in fasting plasma glucose (–21.5 mg/dl versus –3.4 mg/dl) and HbA1c (–0.5% versus –0.3%) levels. Fewer adverse events were reported with vildagliptin/metformin SPC ( n = 16) compared with liraglutide as add-on to metformin treatment ( n = 46).

Conclusions:

In this pilot study, although both vildagliptin and liraglutide therapies were preferred similarly by the patients and showed effective control of glycemia over 12 weeks, vildagliptin was associated with fewer adverse events and was preferred more by elderly patients.
Youssef’s syndrome: Should MRI be the first-line investigation?
Authors: Williams KG , Mathews D , Cooke PW , Blakeman M
Published: July 2015

A 35 year female presented to our department with UTIs, haematuria and urinary incontinence. Cystoscopy demonstrated a bleeding lesion on the posterior wall of the bladder. The possibility of a vesicouterine fistula (Youssef’s syndrome) was therefore raised. Cystography failed to demonstrate the fistula but MRI did. Literature review suggests that the diagnostic pathway for this condition is often lengthy. Our practice now is that MRI is the first line of investigation when a vesicouterine fistula is suspected.
Introducing a new method to assess vision: Computer-adaptive contrast-sensitivity testing predicts visual functioning better than charts in multiple sclerosis patients
Authors: Stellmann JP , Young KL , Pöttgen J , Dorr M , Heesen C
Published: July 2015

Background

Impaired low-contrast visual acuity (LCVA) is common in multiple sclerosis (MS) and other neurological diseases. Its assessment is often limited to selected contrasts, for example, 2.5% or 1.25%. Computerized adaptive testing with the quick contrast-sensitivity function (qCSF) method allows assessment across expanded contrast and spatial frequency ranges.

Objective

The objective of this article is to compare qCSF with high- and low-contrast charts and patient-reported visual function.

Methods

We enrolled 131 consecutive MS patients (mean age 39.6 years) to assess high-contrast visual acuity (HCVA) at 30 cm and 5 m, low-contrast vision with Sloan charts at 2.5% and 1.25%, qCSF and the National Eye Institute Visual Functioning Questionnaire (NEIVFQ). Associations between the different measures were estimated with linear regression models corrected for age, gender and multiple testing.

Results

The association between qCSF and Sloan charts ( R2 = 0.68) was higher than with HCVA (5 m: R2 = 0.5; 30 cm: R2 = 0.41). The highest association with NEIVFQ subscales was observed for qCSF ( R2 0.20–0.57), while Sloan charts were not associated with any NEIVFQ subscale after correction for multiple testing.

Conclusion

The qCSF is a promising new outcome for low-contrast vision in MS and other neurological diseases. Here we show a closer link to patient-reported visual function than standard low- and high-contrast charts.
Rethinking Multiracial Formation in the United States
Authors: Curington Celeste Vaughan
Published: July 2015

This article forwards an integrative multiracial formation perspective that analyzes race, class, and gender as complex social systems, predicated on racism, patriarchy, and economic exploitation. I apply this new framework to three distinct racial projects—slavery, miscegenation law, and the multiracial movement of the 1990s. An analysis of the linkages between the several racial projects that have produced multiraciality over time shows the larger context in which those in power were able to shape the meaning of multiraciality in a way that was created by and constitutive of privilege and power at the intersections of class, gender, and racial hierarchies in the United States.
Reproducing and Reworking Colorblind Racial Ideology
Authors: Hagerman Margaret Ann
Published: July 2015

What is the relationship between white children’s interpretations of racial phenomena and dominant racial ideology? Do children passively adopt dominant racial ideological positions, the result of a “deep cultural conditioning” that happens to children? Do kids assertively challenge ideologies, rejecting adults’ authoritative worldviews through enacting child agency? Or is something more dialectically complex occurring that includes both reproduction and reinvention? Drawing on a subset of data from a two-year ethnographic study with white, affluent families, the author focuses on the relationship between children’s ideas about race and Bonilla-Silva’s four frames of colorblind ideology. The findings demonstrate that rather than adopting colorblind ideology in a prescriptive fashion, children engage in the dialectical process of interpretive reproduction whereby they simultaneously reproduce and rework colorblind ideology, including if, how, and when colorblind frames are used. Acknowledging the active role children play in their own racial socialization, this article complicates the theory of white habitus, arguing for greater recognition of children’s agency and innovation in this socialization process. Exploring this relationship is central to understanding how racism—the ideological sphere of the racialized social system—is reproduced and reworked across generations and how ideal whiteness is dynamic, adapting with the newest generation of whites as they move through different contexts.
Effectiveness of Caregiver Interventions on Patient Outcomes in Adults With Dementia or Alzheimer’s Disease
Authors: Griffin Joan M. , Meis Laura A. , Greer Nancy , MacDonald Roderick , Jensen Agnes , Rutks Indulis , Carlyle Maureen , Wilt Timothy J.
Published: July 2015

Objective: We conducted a systematic review to evaluate whether caregiver-involved interventions improve patient outcomes among adults with dementia or Alzheimer’s disease. Method: We identified and summarized data from randomized controlled trials enrolling adults with dementia or Alzheimer’s disease by searching MEDLINE, PsycINFO, and other sources. Patient outcomes included global quality of life, physical and cognitive functioning, depression/anxiety, symptom control and management, and health care utilization. Results: We identified 31 trials; 20 compared a caregiver intervention with usual care or usual care with promise of intervention at completion of study period. Fifteen compared one caregiver intervention with another individual or caregiver intervention (active control). Compared with usual care or active controls, caregiver-involved interventions had low to insufficient strength of evidence and did not consistently improve patient outcomes. Discussion: Evidence is insufficient to endorse use of most caregiver interventions to improve outcomes for patients with dementia or Alzheimer’s disease.
An Examination of Methods Used to Teach Practice Strategies in the College Voice Studio
Authors: Baughman Melissa
Published: July 2015

This study investigated collegiate voice instructors’ approaches for teaching practice strategies to their students. Voice instructors ( N = 46) from accredited institutions in three Midwestern states participated in a researcher-designed survey, which described (a) the types of practice strategies addressed in lessons, (b) the methods used for assessment, and (c) the value instructors placed on specific practice strategies. Respondents typically used logs and journals to keep track of students’ progress. Score study was valued and used as a practice strategy most often by respondents, but other strategies such as repetition to improve accuracy and focusing on the most difficult sections of the music were also rated highly. Findings suggest that although these collegiate voice instructors seemed to be incorporating a variety of assessment and teaching strategies into their studio instruction, no consistent, formulaic method for teaching college singers to practice could be identified.
Process optimisation of selective laser melting using energy density model for nickel based superalloys
Authors: Carter L. N. , Wang X. , Read N. , Khan R. , Aristizabal M. , Essa K. , Attallah M. M.
Published: July 2015

The main challenge associated with the application of selective laser melting (SLM) to Ni based superalloys is the performance of process optimisation to maximise the mechanical properties. The energy density parameter has typically been used as a semiquantitative approach to identify the energy threshold beyond which the material achieves virtually full consolidation. Nonetheless, some Ni superalloys are susceptible to crack formation during SLM, which cannot be avoided via process optimisation. In the present report, a comparative study is presented showing the utility of the energy density parameter in process optimisation for γ′ and γ′/γ″ strengthened Ni based superalloys. For both classes, it was found that the build density increases [i.e. void area () decreases] with the increase in the energy density. Nonetheless, no direct correlation can be found between the energy density parameter and the cracking density.
Growth of dip coated magnesium oxide nanoflower thin films
Authors: Das P. S. , Dey A. , Mandal A. K. , Dey N. , Mukhopadhyay A. K.
Published: July 2015

The present work reports the synthesis of dip coated MgO nanoflower thin films. The films are developed without employing any capping agent and catalyst. A simple chemical deposition technique is adopted for this purpose. The MgO nanoflower thin films are characterised by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy and the related energy dispersive X-ray spectroscopy techniques. The results establish the phase purity and microstructural details of the MgO nanoflower thin films. These results are explained in terms of a proposed mechanism that suggests the growth process for the MgO nanoflower structures.
Mutations in the Gardos channel (KCNN4) are associated with hereditary xerocytosis
Authors: Glogowska Edyta , Lezon-Geyda Kimberly , Maksimova Yelena , Schulz Vincent P. , Gallagher Patrick G.
Published: July 2015

Key Points

Mutations in the Gardos channel, encoded by the KCNN4 gene, were identified in individuals from 2 hereditary xerocytosis kindreds. These findings support recent data indicating the Gardos channel plays a role in normal erythrocyte volume homeostasis.
Single-cell RNA-seq transcriptome analysis of linear and circular RNAs in mouse preimplantation embryos
Authors: Fan Xiaoying , Zhang Xiannian , Wu Xinglong , Guo Hongshan , Hu Yuqiong , Tang Fuchou , Huang Yanyi
Published: July 2015

Circular RNAs (circRNAs) are a new class of non-polyadenylated non-coding RNAs that may play important roles in many biological processes. Here we develop a single-cell universal poly(A)-independent RNA sequencing (SUPeR-seq) method to sequence both polyadenylated and non-polyadenylated RNAs from individual cells. This method exhibits robust sensitivity, precision and accuracy. We discover 2891 circRNAs and 913 novel linear transcripts in mouse preimplantation embryos and further analyze the abundance of circRNAs along development, the function of enriched genes, and sequence features of circRNAs. Our work is key to deciphering regulation mechanisms of circRNAs during mammalian early embryonic development.
Embracing risk
Authors: Cagan Ross
Published: July 2015

I entered the science field because I imagined that scientists were society's “professional risk takers”, that they like surfing out on the edge. I understood that a lot of science – perhaps even most science – has to be a solid exploration of partly understood phenomena. But any science that confronts a difficult problem has to start with risk. Most people are at least a bit suspicious of risk, and scientists such as myself are no exception. Recently, risk-taking has been under attack financially, but this Editorial is not about that. I am writing about the long view and the messages we send to our trainees. I am Senior Associate Dean of the graduate school at Mount Sinai and have had the privilege to discuss these issues with the next generation of scientists, for whom I care very deeply. Are we preparing you to embrace risk?
Sprint sensitivity and locomotor trade-offs in green anole (Anolis carolinensis) lizards
Authors: Sathe Erik A. , Husak Jerry F.
Published: July 2015

How well an organism completes an ecologically relevant task – its performance – is often considered a key factor in determining individual fitness. Historically, ecomorphological studies have examined how morphological traits determine individual performance in a static manner, assuming that differential fitness in a population is due indirectly to differences in morphological traits that determine a simple measure of performance. This assumption, however, ignores many ecological factors that can constrain performance in nature, such as substrate variation and individual behavior. We examined some of these complexities in the morphology–performance–fitness paradigm, primarily the impact that substrate variation has on performance. We measured maximal sprint speed of green anole lizards on four substrates that varied in size and complexity and are used by or available to individuals in nature. Performance decreased significantly from a broad substrate to a narrow substrate, and lizards were three times slower on a complex substrate than the broadest substrate. We also detected trade-offs in running on substrates with different diameters and in cluttered versus uncluttered environments. Furthermore, morphological predictors of performance varied among substrates. This indicates that natural selection may act on different morphological traits, depending on which substrates are used by individuals, as well as an individual's ability to cope with changes in substrate rather than maximal capacities.
How to know which food is good for you: bumblebees use taste to discriminate between different concentrations of food differing in nutrient content
Authors: Ruedenauer Fabian A. , Spaethe Johannes , Leonhardt Sara D.
Published: July 2015

In view of the ongoing pollinator decline, the role of nutrition in bee health has received increasing attention. Bees obtain fat, carbohydrates and protein from pollen and nectar. As both excessive and deficient amounts of these macronutrients are detrimental, bees would benefit from assessing food quality to guarantee an optimal nutrient supply. While bees can detect sucrose and use it to assess nectar quality, it is unknown whether they can assess the macronutrient content of pollen. Previous studies have shown that bees preferentially collect pollen of higher protein content, suggesting that differences in pollen quality can be detected either by individual bees or via feedback from larvae. In this study, we examined whether and, if so, how individuals of the buff-tailed bumblebee (Bombus terrestris) discriminate between different concentrations of pollen and casein mixtures and thus nutrients. Bumblebees were trained using absolute and differential conditioning of the proboscis extension response (PER). As cues related to nutrient concentration could theoretically be perceived by either smell or taste, bees were tested on both olfactory and, for the first time, chemotactile perception. Using olfactory cues, bumblebees learned and discriminated between different pollen types and casein, but were unable to discriminate between different concentrations of these substances. However, when they touched the substances with their antennae, using chemotactile cues, they could also discriminate between different concentrations. Bumblebees are therefore able to discriminate between foods of different concentrations using contact chemosensory perception (taste). This ability may enable them to individually regulate the nutrient intake of their colonies.
Tailoring of Surface Chirality by Micro-Vortices and Specific Adsorption in Magnetoelectrodeposition
Authors: Mogi Iwao , Aogaki Ryoichi , Watanabe Kazuo
Published: July 2015

Solid surfaces often serve as a reaction field for organic molecules. If a surface has chirality, it could play a significant role as an enantioselective catalyst. Electrodeposition in magnetic fields (magnetoelectrodeposition; MED) has potential to produce enantioselective metal surfaces, however, the exploration of chiral formation conditions has not been sufficient in previous MED experiments. Here we show the chiral behaviors of copper film surfaces prepared by galvanostatic MED. We found that the chiral sign depends on both the deposition current and the polarity of magnetic field. Furthermore, we found that the specific adsorption of chloride ions on the film surfaces brings about drastic influence on the chiral formation in MED. At certain chloride concentrations chiral symmetry breaking was observed for the polarity of magnetic field. These findings imply that magnetohydrodynamic micro-vortices and the rate-limiting steps are responsible for the chiral surface formation.
Comparing the Robustness of Offshore Structures with Marine Deteriorations — A Fuzzy Approach
Authors: Zhang Y.
Published: July 2015

The safety of offshore structures is highly dependent on the marine environment, where the latter could result damages to the structures through the deterioration process. A realistic analysis of the offshore structural performance with marine deteriorations is a challenging task. The traditional probabilistic model is sometimes too biased and could lead to undesirable results since the available information regarding the corrosion process is usually quite imprecise and uncertain. In this paper, the robustness assessment of offshore structures with consideration of corrosion effect is investigated through the fuzzy concept. The fuzzy model is introduced to quantify the thickness reduction associated with the corrosion process. The uncertainty regarding the time varying effect of the ultimate strength is analyzed in the computation to reflect the structural deterioration process. The concept of entropy is used to measure the degree of uncertainties in the input and output of a structural model in the robustness assessment. In order to demonstrate this innovation, this paper selects several similar structural models and compares their performances for the same level of damage imprecision. The results are also compared to the traditional probabilistic assessment methods and the experimental models in the literature. The advantage of applying this concept is shown in the results for comparing the performances of different structural systems with various intensities of imprecision in the input parameter. The comparison also demonstrates different cases while the corrosion process is extended to longer period.
Influence of Concrete Compressive Strength on the Arching Behaviour of Reinforced Concrete Beam Assemblages
Authors: Pour H. Vali , Vessali N. , Foster S.J. , Samali B.
Published: July 2015

The influence of concrete compressive strength on the loading capacity of purely flexural RC members is minor; however, the beneficial effect of concrete compressive strength on the ultimate loading capacity of axially restrained RC beams can be fairly significant due to development of compressive arch action. Accordingly, in this study, six 2/5th scale restrained RC beam assemblages with various concrete compressive strength (ranging from 18 MPa to 67 MPa) and two different longitudinal steel bar arrangements are tested to establish the relationship between concrete compressive strength and ultimate loading capacity of restrained RC beam assemblages. In addition, nonlinear finite element (FE) model of the tested RC beam assemblages with different boundary conditions were developed and a good correlation between experimental results and FE predictions was observed. With regard to the results captured by the lab tests and nonlinear FE models, it is concluded that the ultimate loading capacity of axially restrained RC beams has an almost linear relationship with compressive strength of concrete and the slope of this line depends on the translational stiffness of end supports (along the beam axis).
Large-amplitude vibration of imperfect angle-ply laminated rectangular plate with viscous damping
Authors: Huang He , Hui David
Published: July 2015

This paper solves the modified-Duffing ordinary differential equation for large-amplitude vibration of imperfect angle-ply rectangular composite plate. Viscous damping is then introduced in the derivation and analyzed under four different boundary conditions (combining two out-of-plane boundary conditions with two in-plane boundary conditions). It has been shown that even a small viscous damping factor, for example 0.1 from an ordinary damped system can largely decrease the vibration amplitude within several periods. Yet at the same time, the vibration frequency only changes slightly. Furthermore, viscous damping is proved to significantly affect the vibration frequency and the vibration mode from nonlinear to much more linear. This effect is irrelevant to boundary conditions and geometric imperfections.
Exergoeconomic analysis and performance assessment of selected gas turbine power plants
Authors: Oyedepo S.O. , Fagbenle R.O. , Adefila S.S. , Alam Md. Mahbub
Published: July 2015

In this study, exergoeconomic analysis and performance evaluation of selected gas turbine power plants in Nigeria were carried out. The study was conducted using operating data obtained from the power plants to determine the exergy efficiency, exergy destruction, unit cost of electricity and cost of exergy destruction of the major components of a gas turbine engine in the selected power plants. The results of exergy analysis confirmed that the combustion chamber is the most exergy destructive component compared to other cycle components as expected. The total efficiency defects and overall exergetic efficiency of the selected power plants vary from 38.64 to 69.33% and 15.66 to 30.72% respectively. The exergy analysis further shows that the exergy improvement potential of the selected plants varies from 54.04 MW to 159.88 MW. The component with the highest exergy improvement potential is the combustion chamber and its value varies from 30.21 MW to 88.86 MW. The results of exergoeconomic analysis show that the combustion chamber has the greatest cost of exergy destruction compared to other components. Increasing the gas turbine inlet temperature (GTIT), both the exergy destruction and the cost of exergy destruction of this component were found to decrease. The results of this study revealed that an increase in the GTIT of about 200 K can lead to a reduction of about 29% in the cost of exergy destruction. From exergy costing analysis, the unit cost of electricity produced in the selected power plants varies from cents 1.99 /kWh (N3.16 /kWh) to cents 5.65 /kWh (N8.98 /kWh).
O6-Methylguanosine leads to position-dependent effects on ribosome speed and fidelity
Authors: Hudson Benjamin H. , Zaher Hani S.
Published: July 2015

Nucleic acids are under constant assault from endogenous and environmental agents that alter their physical and chemical properties. O6-methylation of guanosine (m6G) is particularly notable for its high mutagenicity, pairing with T, during DNA replication. Yet, while m6G accumulates in both DNA and RNA, little is known about its effects on RNA. Here, we investigate the effects of m6G on the decoding process, using a reconstituted bacterial translation system. m6G at the first and third position of the codon decreases the accuracy of tRNA selection. The ribosome readily incorporates near-cognate aminoacyl-tRNAs (aa-tRNAs) by forming m6G-uridine codon–anticodon pairs. Surprisingly, the introduction of m6G to the second position of the codon does not promote miscoding, but instead slows the observed rates of peptide-bond formation by >1000-fold for cognate aa-tRNAs without altering the rates for near-cognate aa-tRNAs. These in vitro observations were recapitulated in eukaryotic extracts and HEK293 cells. Interestingly, the analogous modification N6-methyladenosine (m6A) at the second position has only a minimal effect on tRNA selection, suggesting that the effects on tRNA selection seen with m6G are due to altered geometry of the base pair. Given that the m6G:U base pair is predicted to be nearly indistinguishable from a Watson-Crick base pair, our data suggest that the decoding center of the ribosome is extremely sensitive to changes at the second position. Our data, apart from highlighting the deleterious effects that these adducts pose to cellular fitness, shed new insight into decoding and the process by which the ribosome recognizes codon–anticodon pairs.