bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pediatric Versus Adult Drug Trials for Conditions With High Pediatric Disease Burden
Authors: Bourgeois Florence T. , Murthy Srinivas , Pinto Catia , Olson Karen L. , Ioannidis John P.A. , Mandl Kenneth D. 
Published: July 2012

BACKGROUND AND OBJECTIVE:
Optimal treatment decisions in children require sufficient evidence on the safety and efficacy of pharmaceuticals in pediatric patients. However, there is concern that not enough trials are conducted in children and that pediatric trials differ from those performed in adults. Our objective was to measure the prevalence of pediatric studies among clinical drug trials and compare trial characteristics and quality indicators between pediatric and adult drug trials.

METHODS:
For conditions representing a high burden of pediatric disease, we identified all drug trials registered in ClinicalTrials.gov with start dates between 2006 and 2011 and tracked the resulting publications. We measured the proportion of pediatric trials and subjects for each condition and compared pediatric and adult trial characteristics and quality indicators.

RESULTS:
For the conditions selected, 59.9% of the disease burden was attributable to children, but only 12.0% (292/2440) of trials were pediatric (P &lt; .001). Among pediatric trials, 58.6% were conducted without industry funding compared with 35.0% of adult trials (P &lt; .001).
Fewer pediatric compared with adult randomized trials examined safety outcomes (10.1% vs 16.9%, P = .008). Pediatric randomized trials were slightly more likely to be appropriately registered before study start (46.9% vs 39.3%, P = .04) and had a modestly higher probability of publication in the examined time frame (32.8% vs 23.2%, P = .04).

CONCLUSIONS:
There is substantial discrepancy between pediatric burden of disease and the amount of clinical trial research devoted to pediatric populations. This may be related in part to trial funding, with pediatric trials relying primarily on government and nonprofit organizations.
Dynamics Induced by Femtosecond Laser and Photovoltaic Phenomena Studied by Using Time-Dependent First Principles Method
Authors: Miyamoto Yoshiyuki 
Published: July 2012

ABSTRACTIn this work, the first-principles computational scheme of electron-ion dynamics based on the time-dependent density functional theory is presented as a tool to study dynamical phenomena induced by light. Two applications of computations for photo-induced phenomena are shown. The one is structural change induced by intense and short laser shot with a purpose to simulate experiments using the femtosecond laser. The other is photo-excitation and subsequent carrier splitting into electrons and holes, which is a key process needed in photovoltaic materials.
Pulsed Laser Modification of the Growth of Ge Quantum Dots on Si(100)-(2x1)
Authors: Er Ali Oguz , Elsayed-Ali Hani E. 
Published: July 2012

ABSTRACTGe quantum dots were grown on Si(100)-(2x1) using pulsed laser deposition while the laser is also exciting the substrate during film growth. The growth mode and morphology was probed by scanning tunneling microscopy (STM). Epitaxial growth at a substrate temperature of ∼250 °C was achieved by using laser excitation of the substrate. The morphology of the quantum dots changed with increased laser excitation energy density although the faceting of the individual quantum dots remained the same. A purely electronic mechanism of enhanced surface diffusion of the Ge adatoms is proposed.
Laser cleaning of exfoliated graphene
Authors: Ochedowski Oliver , Bußmann Benedict Kleine , Schleberger Marika 
Published: July 2012

ABSTRACTWe have employed atomic force and Kelvin-Probe force microscopy to study graphene sheets exfoliated on TiO2 under the influence of local heating achieved by laser irradiation. Exfoliation and irradiation took place under ambient conditions, the measurements were performed in ultra high vacuum. We show that after irradiation times of 6 min, an increase of the surface potential is observed which indicates a decrease of p-type carrier concentration. We attribute this effect to the removal of adsorbates like water and oxygen. After irradiation times of 12 min our topography images reveal severe structural modifications of graphene. These resemble the nanocrystallite network which form on graphene/SiO2 but after much longer irradiation times. From our results we propose that short laser heating at moderate powers might offer a way to clean graphene without inducing unwanted structural modifications.
Long-term Adhesion Studies of Polyimide to Inorganic and Metallic Layers
Authors: Ordonez Juan S. , Boehler Christian , Schuettler Martin , Stieglitz Thomas 
Published: July 2012

ABSTRACTDelamination between thin-film metal and substrate is a major cause of failure in polyimide based neural microelectrode arrays. Chemical adhesion is the only way to establish a long-term bond that will allow two materials to stick to each other even in a wet environment, given that the materials do not deteriorate in the presence of water. This study assesses, by means of peel and shear tests, a long-term quantitative and comparative study of the adhesion of polyimide to various metallic and other inorganic layers of interest. Polyimide (BPDA-PPD) was cured on the layers, which involve platinum, gold and tungsten-titanium as commonly used implant metals and diamond-like carbon (DLC), silicon carbide (SiC), silicon dioxide (SiO2) and silicone nitride (SiN) as potential adhesion promoters to be used later as intermediate layers between metal and polyimide. The adhesion was observed over one year under accelerated-aging conditions by storing the specimens in 60°C saline (corresponding to 40000 hrs at 37°C). Only silicon carbide and amorphous carbon showed almost unaffected adhesion to polyimide over the testing period. No water intrusion at the interface was observed and the strong bond is almost fully maintained.
Knowledge Diversity in the Emerging Global Bio-Nano Sector
Authors: Maine Elicia , Bliemel Martin , Murira Armstrong , Utterback James 
Published: July 2012

ASTRACTAs scientists are able to understand and manipulate ever smaller scales of matter, research in the fields of biotechnology and nanotechnology has converged to enable such radical innovations as lab-on-a-chip devices, targeted drug delivery, and other forms of minimally invasive therapy and diagnostics. This paper provides a descriptive overview of the emerging bio-nano sector, identifying what types of firms are entering, from what knowledge base, where they are located, and their strategic choices in terms of technological diversity and R&D strategy. The firms engaged in bio-nano research and development span the range from start-up firm to multinational pharmaceutical, biotech, chemical, and electronics firms: two thirds of bio-nano firms are relatively young and relatively small. The United States dominates this sector, with more than half of all bio-nano firms located in the USA. Even within this sector which epitomizes the convergence of technology, there is a broad range of technological diversity, with the most diverse firms overall coming from a base in electronics, the most diverse start-up firms coming from a base in nanomaterials, and the most narrowly focused firms coming from a biotechnology/pharmaceutical base. We find that hybridization has been the dominant knowledge diversity strategy, with 93% of the bio-nano firms with nano-patents holding multiclass patents.
Magnetic properties of Fe-pnictides superconductors as a function of pressure and doping
Authors: Profeta Gianni , Colonna Nicola , Continenza Alessandra 
Published: July 2012

ABSTRACTWe present a first principles study of the electronic and magnetic properties of Fe-based pnicitdes superconductors as a function of pressure and doping. We show that the magnetic phase and a local magnetic moment persists at doping level quite larger than what found in experiments and the pressure phase diagram consists of a paramagnetic, antiferromagnetic and non-magnetic phases.Although this result calls for the inclusion of long-wavelength or local fluctuations of iron magnetic moment and non-hydrostatic pressure effects, in order to improve the theoretical description of real experimental conditions, recent photoemission experiments[1] reconcile these DFT results, showing a local magnetic moment on Fe site different from zero in the paramagnetic, antiferromagnetic and the superconducting phase.
Morphology-induced hydrophobic behavior of electrospun polyhydroxyalkanoate membranes
Authors: Domínguez-Díaz Maraolina , Romo-Uribe Angel , Flores Araceli , Cruz-Silva Rodolfo 
Published: July 2012

ABSTRACTBiodegradable poly(3-hydroxybutyrate) -PHB- and the copolymers with poly (3-hydroxyvalerate) -PHB/HV, containing 5 and 12 mol% valerate (denoted PHB/5HV and PHB/12HV, respectively) were electrospun from chloroform solution at room temperature. The results showed that relatively low voltage and concentrations favored uniform filament formation in PHB, with filament diameters ranging from 3 to 7 micrometers. On the other hand, low molecular weight and low solution concentration favored uniform filament formation in the PHB/5HV copolymer. Strikingly, morphology of filaments and beads favored the membranes hydrophobic behavior; the membrane from PHB/12HV exhibited a water contact angle of 112°. In contrast, solution cast films from the PHAs exhibited water contact angles in the range of 65°. Analyses on the membranes morphology via scanning electron microscopy (SEM) revealed that filament diameter drives the degree of porosity and the hydrophobic behavior of the electrospun membranes.
Photonic active filters based on SiC multilayer structures
Authors: Vieira M. A. , Vieira M. , Louro P. , Silva V. , Costa J. , Barata M. 
Published: July 2012

ABSTRACTTunable WDM converters based on amorphous SiC multilayer photonic active filters are analyzed. The manipulation of the magnitude is achieved through appropriated front and back backgrounds. Transfer function characteristics are studied. Results show that the light-activated device combines the demultiplexing operation with the simultaneous photodetection and self amplification of an optical signal. Depending on the wavelength of the external background and irradiation side, it acts either as a short- or a long- pass band filter or as a band-stop filter. A combinational logic function is mapped onto an active two stage optoelectronic logic circuit. An algorithm to decode the multiplex signal is established. An optoelectronic model supports the optoelectronic logic architecture.
Graphene-Based All-Solid-State Supercapacitor with Ionic Liquid Gel Polymer Electrolyte
Authors: Pandey G. P. , Rastogi A. C. 
Published: July 2012

ABSTRACTGraphene-based all-solid-state supercapacitors the using ionic liquid gel polymer electrolyte have been fabricated and characterized. The gel polymer electrolyte has been prepared by immobilizing ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate (BMIBF4) with poly(vinylidene fluoride-hexafluoropropylene). Cyclic voltammetry studies show highly capacitive behavior under fast scan rates. Impedance analysis show nominal charge transfer and ion diffusion at pores related resistance contributions. The graphene-based solid-state supercapacitor shows optimum capacitance of 80 mF cm-2 (equivalent to the single electrode specific capacitance of 76 F g-1). This corresponded to the specific energy of 7.4 Wh kg-1 and specific power of 4.5 kW kg-1. The supercapacitor cell shows stable cyclic performances for up to 5000 cycles and possibly beyond.
Modification of High Potential, High Capacity Li2FeP2O7Cathode Material for Lithium Ion Batteries
Authors: Tan Jiajia , Tiwari Ashutosh 
Published: July 2012

ABSTRACTLi2FeP2O7is a newly developed polyanionic cathode material for high performance lithium ion batteries. It is considered very attractive due to its large specific capacity, good thermal and chemical stability, and environmental benignity. However, the application of Li2FeP2O7is limited by its low ionic and electronic conductivities. To overcome the above problem, a solution-based technique was successfully developed to synthesize Li2FeP2O7powders with very fine and uniform particle size (< 1 μm), achieving much faster kinetics. The obtained Li2FeP2O7powders were tested in lithium ion batteries by measurements of cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge/discharge cycling. We found that the modified Li2FeP2O7cathode could maintain a relatively high capacity even at fast discharge rates.
Block Copolymer Assisted Fabrication of Graphene/Carbon Nanotube Hybrid Architectures and Their Application in Supercapacitors
Authors: George Aaron S. , Ghazinejad Maziar , Wang Wei , Ruiz Isaac , Ozkan Mihrimah , Ozkan Cengiz S. 
Published: July 2012

AbstractSustainable energy is currently limited by the ability of materials to store energy and deliver it on demand. Allotropes of carbon are attractive for their potential for use in energy storage due to low weight, high chemical stability and low production cost. Carbon nanotubes and graphene can be combined to provide an effective three-dimensional material with high conductivity and high surface area. We demonstrate the use of block copolymers to obtain patterned arrays of iron nanoparticles which give rise to ordered carbon nanotubes with good size distribution. A one-step chemical vapor deposition process for large-area fabrication of the graphene and carbon nanotube hybrid structure is described. Following chemical vapor deposition the hybrid material is demonstrated in a supercapacitor device. The fabricated supercapacitor exhibits high electrical conductivity, and has potential for extremely high energy storage capability.
Design Considerations to Improve Transport in Porous Electrodes for Lithium-Ion Batteries
Authors: Chandrasekaran Rajeswari , Drews Andrew , Shaligram Apoorv , Sakamoto Jeffrey 
Published: July 2012

ABSTRACTThe relationship between tortuosity and porosity and its influence on effective transport properties in lithium-ion cells was analyzed. The variation in cell performance with changes in component thicknesses, porosities and tortuosities was investigated. Optimal, novel electrode designs are developed to improve their rate capability even at higher active material loadings.
US Health Policy Related to Hookah Tobacco Smoking
Authors: Primack Brian A. , Hopkins Maggie , Hallett Cynthia , Carroll Mary V. , Zeller Mitchell , Dachille Kathleen , Kim Kevin H. , Fine Michael J. , Donohue Julie M. 
Published: July 2012

Objectives. Although US cigarette smoking is decreasing, hookah tobacco smoking (HTS) is an emerging trend associated with substantial toxicant exposure. We assessed how a representative sample of US tobacco control policies may apply to HTS. Methods. We examined municipal, county, and state legal texts applying to the 100 largest US cities. We developed a summary policy variable that distinguished among cities on the basis of how current tobacco control policies may apply to HTS and used multinomial logistic regression to determine associations between community-level sociodemographic variables and the policy outcome variable. Results. Although 73 of the 100 largest US cities have laws that disallow cigarette smoking in bars, 69 of these cities have exemptions that allow HTS; 4 of the 69 have passed legislation specifically exempting HTS, and 65 may permit HTS via generic tobacco retail establishment exemptions. Cities in which HTS may be exempted had denser populations than cities without clean air legislation. Conclusions. Although three fourths of the largest US cities disallow cigarette smoking in bars, nearly 90% of these cities may permit HTS via exemptions. Closing this gap in clean air regulation may significantly reduce exposure to HTS.
Relationship between Uric Acid Levels and Diagnostic and Prognostic Outcomes in Acute Heart Failure
Authors: Henry-Okafor Queen , P. Collins Sean , A. Jenkins Cathy , F. Miller Karen , J. Maron David , J. Naftilan Allen , Weintraub Neal , J. Fermann Gregory , McPherson John , Menon Santosh , B. Sawyer Douglas , B. Storrow Alan 
Published: July 2012

Objectives:
We evaluated the association of plasma uric acid alone and in combination with b-type natriuretic peptide (BNP) for emergency department (ED) diagnosis and 30-day prognosis in patients evaluated for acute heart failure (AHF).

Methods:
We prospectively enrolled 322 adult ED patients with suspected AHF. Wilcoxon rank sum test, multivariable logistic regression and likelihood ratio (LR) tests were used for statistical analyses.

Results:
Uric acid's diagnostic utility was poor and failed to show significant associations with 30-day clinical outcomes. Uric acid also did not add significantly to BNP results.

Conclusion:
Among ED patients with suspected AHF, uric acid has poor diagnostic and prognostic utility
The Ability of Clinical Tests to Diagnose Stress Fractures: A Systematic Review and Meta-analysis
Authors: Schneiders Anthony G. , Sullivan S. John , Hendrick Paul A. , Hones Benjamin D.G.M. , McMaster Andrew R. , Sugden Bridget A. , Tomlinson Celia 
Published: July 2012

Study Design Systematic literature review and meta-analysis. Objectives To evaluate the diagnostic accuracy of clinical tests to identify stress fractures in the lower limb. Background Stress fractures are a bone-related overuse injury primarily occurring in the lower limb and commonly affecting running athletes and military personnel. Physical examination procedures and clinical tests are suggested for diagnosing stress fractures; however, data on the diagnostic accuracy of these tests have not been investigated through a systematic review of the literature. Methods A systematic review was conducted in 8 electronic databases to identify diagnostic accuracy studies, published between January 1950 and June 2011, that evaluated clinical tests against a radiological diagnosis of lower-limb stress fracture. Retrieved articles were evaluated using the Quality Assessment of Diagnostic Accuracy Studies tool, and a meta-analysis was performed where appropriate. Results Nine articles investigating 2 clinical procedures, therapeutic ultrasound (n = 7) and tuning fork testing (n = 2), met the study inclusion criteria. Meta-analysis was used to statistically analyze the data extracted from the ultrasound articles and demonstrated a pooled sensitivity of 64% (95% confidence interval [CI]: 55%, 73%), specificity of 63% (95% CI: 54%, 71%), positive likelihood ratio of 2.1 (95% CI: 1.1, 3.5), and negative likelihood ratio of 0.3 (95% CI: 0.1, 0.9). Tuning fork test data could not be pooled; however, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio ranged from 35% to 92%, 19% to 83%, 0.6 to 3.0, and 0.4 to 1.6, respectively. Conclusion The results of this systematic review do not support the specific use of ultrasound or tuning forks as standalone diagnostic tests for lower-limb stress fractures. As the overall diagnostic accuracy of the tests investigated is not strong, based on the calculated likelihood ratios, it is recommended that radiological imaging should continue to be used for the confirmation and diagnosis of stress fractures of the lower limb. Level of Evidence Diagnosis, level 1a-. J Orthop Sports Phys Ther 2012;42(9):760–771, Epub 19 July 2012. doi:10.2519/jospt.2012.4000
Performance of Tomato Varieties during Rainy Season under Plastic House Conditions
Authors: Chapagain Tika R , Khatri Bhim B , Mandal Jawahar L 
Published: July 2012

Plastic house technology and arrival of hybrid varieties have increased the possibility of tomato cultivation in rainy season in high hills. An experiment was conducted to assess the performance of tomato varieties under plastic house for two consecutive years from 2009 to 2010 at National Commercial Agriculture Research Program (NCARP), Pakhribas (1750m), Nepal. The experiment consisted of eight tomato varieties namely, All Rounder, Bishesh, Dalila, Manisha, Srijna, Suraksha, Trishul and US-04 laid out in a randomized complete block design with three replications. The varieties differed significantly for all observed traits. The highest marketable yield was recorded from All Rounder (86.6 t ha-1) followed by Srijana (80.8 t ha-1). Srijana took the shortest period for flowering and harvesting with an average of 37 and 77 days after transplanting respectively. This was also the tallest variety (268.7 cm) with more clusters (36.23) per plant. However, the highest average single fruit weight was recorded from Manisha (61.94g), and the largest fruit size in US-04 with a diameter of 5.78 cm. Based on yield parameter, the varieties All Rounder and Srijana are recommended for commercial cultivation under plastic house conditions.DOI: http://dx.doi.org/10.3126/njst.v12i0.6473 Nepal Journal of Science and Technology 12 (2011) 17-22
Supplementation of Broilers Diet with Different Sources of Growth Promoters
Authors: Sanjyal S , Sapkota S 
Published: July 2012

A study was conducted at the Institute of Agriculture and Animal Sciences (IAAS), Rampur, Chitwan from 29 August to 17 October, 2007 to compare the effects of antibiotic (chlortetracycline) and probiotic (Lactobacillus acidophilus) with three herbal growth promoters, Amala (Emblica officinalis),(EO), Tulsi (Ocimum sanctum), (OC) and Aswogandha (Withania somnifera),(WS) on growth performance, feed consumption, feed conversion efficiency, carcass characteristics, and economics of broiler production. The experiment was laid out in a completely randomized design with day-old broiler chick (192) randomly assigned to eight groups containing 8 chick in each and replicated three times. The control group received the maize-soybean based basal diet. In the treatment groups, the basal diet was supplemented with one of the following: antibiotic, probiotics, Tulsi, Amala, and Aswogandha and also in combination of herbs, forming eight treatments respectively. Results showed significantly better production in herbs. Significantly higher digestibility of all the nutrients (P<0.05) was observed in Amala+Tulsi+Aswogandha (T8) supplemented group. Highest body weight (1.440kg) was recorded in birds fed diet supplemented with Amala and Tulsi, and the lowest body weight (1.317kg) was seen in antibiotics (T2) fed birds. The highest income over expenditure (Rs.26.36) was recorded in birds fed diet supplemented with Tulsi (T6), although the difference was not significant among the treatments. Looking at the benefit cost ratio, highest B/C ratio was found in birds supplied with Tulsi (1.19) supplemented diet and minimum (1.12) was recorded in Amala supplied diet. Hence, this experiment showed that herbs as growth promoters can replace antibiotics in the diet of broiler chicken. However, it needs multilocational trials before recommendation for adoption by poultry growers.DOI: http://dx.doi.org/10.3126/njst.v12i0.6478 Nepal Journal of Science and Technology 12 (2011) 41-50