1,999 research outputs found
Los jóvenes y su orientación hacia los medios de comunicación en Brasil, Chile y Ecuador.
Sin resume
Parents' perceived obstacles to pediatric clinical trial participation: Findings from the clinical trials transformation initiative.
Enrollment of children into pediatric clinical trials remains challenging. More effective strategies to improve recruitment of children into trials are needed. This study used in-depth qualitative interviews with parents who were approached to enroll their children in a clinical trial in order to gain an understanding of the barriers to pediatric clinical trial participation. Twenty-four parents whose children had been offered the opportunity to participate in a clinical trial were interviewed: 19 whose children had participated in at least 1 clinical trial and 5 who had declined participation in any trial. Each study aspect, from the initial explanation of the study to the end of the study, can affect the willingness of parents to consent to the proposed study and future studies. Establishing trust, appropriate timing, a transparent discussion of risks and benefits oriented to the layperson, and providing motivation for children to participate were key factors that impacted parents' decisions. In order for clinical trial accrual to be successful, parents' priorities and considerations must be a central focus, beginning with initial trial design. The recommendations from the parents who participated in this study can be used to support budget allocations that ensure adequate training of study staff and improved staffing on nights and weekends. Studies of parent responses in outpatient settings and additional inpatient settings will provide valuable information on the consent process from the child's and parent's perspectives. Further studies are needed to explore whether implementation of such strategies will result in improved recruitment for pediatric clinical trials
Perceived barriers to pediatrician and family practitioner participation in pediatric clinical trials: Findings from the Clinical Trials Transformation Initiative.
Despite legislation to stimulate pediatric drug development through clinical trials, enrolling children in trials continues to be challenging. Non-investigator (those who have never served as a clinical trial investigator) providers are essential to recruitment of pediatric patients, but little is known regarding the specific barriers that limit pediatric providers from participating in and referring their patients to clinical trials. We conducted an online survey of pediatric providers from a wide variety of practice types across the United States to evaluate their attitudes and awareness of pediatric clinical trials. Using a 4-point Likert scale, providers described their perception of potential barriers to their practice serving as a site for pediatric clinical trials. Of the 136 providers surveyed, 52/136 (38%) had previously referred a pediatric patient to a trial, and only 17/136 (12%) had ever been an investigator for a pediatric trial. Lack of awareness of existing pediatric trials was a major barrier to patient referral by providers, in addition to consideration of trial risks, distance to the site, and time needed to discuss trial participation with parents. Overall, providers perceived greater challenges related to parental concerns and parent or child logistical barriers than study implementation and ethics or regulatory barriers as barriers to their practice serving as a trial site. Providers who had previously been an investigator for a pediatric trial were less likely to be concerned with potential barriers than non-investigators. Understanding the barriers that limit pediatric providers from collaboration or inhibit their participation is key to designing effective interventions to optimize pediatric trial participation
The origin of GEMS in IDPs as deduced from microstructural evolution of amorphous silicates with annealing
We present laboratory studies of the micro-structural evolution of an
amorphous ferro-magnesian silicate, of olivine composition, following thermal
annealing under vacuum. Annealing under vacuum was performed at temperatures
ranging from 870 to 1020 K. After annealing spheroidal metallic nano-particles
(2-50 nm) are found within the silicate films. We interpret this microstructure
in terms of a reduction of the initial amorphous silicate FeO component,
because of the carbon-rich partial pressure in the furnace due to pumping
mechanism. Annealing in a controlled oxygen-rich atmosphere confirms this
interpretation. The observed microstructures closely resemble those of the GEMS
(Glass with Embedded Metal and Sulphides) found in chondritic IDPs
(Interplanetary Dust Particles). Since IDPs contain abundant carbonaceous
matter, a solid-state reduction reaction may have occurred during heating in
the hot inner regions of the proto-solar disc. Related to this, the presence of
forsterite grains grown from the amorphous precursor material clearly
demonstrates that condensation from gaseous species is not required to explain
the occurrence of forsterite around young protostars and in comets. Forsterite
grains in these environments can be formed directly in the solid phase by
thermal annealing of amorphous ferro-magnesian silicates under reducing
conditions.Comment: 4 pages, 2 figures. Accepted for publication A&A Letter to the Edito
Impact of prior biologic use on persistence of treatment in patients with psoriatic arthritis enrolled in the US Corrona registry
Psoriatic arthritis (PsA) is a chronic condition characterized by a diverse set of symptoms, from swollen joints to nail disease to skin disease. A variety of treatment options are available, including tumor necrosis factor inhibitors (TNFis). Little is known about treatment persistence in patients with PsA who initiate TNFi therapy, with and without prior biologic use. This study assessed persistence in these subgroups of patients with PsA and identified factors associated with persistence. This retrospective study utilized data from the Corrona registry of patients with PsA-with or without prior biologic experience-who initiated TNFi therapy between October 1, 2002, and March 21, 2013. Kaplan-Meier curves estimated median time to nonpersistence (discontinuation or switch to another biologic). Cox proportional hazards models identified factors associated with TNFi nonpersistence. A total of 1241 TNFi initiations were identified: 549 by biologic-naive and 692 by biologic-experienced patients. Through 4 years of follow-up, more biologic-naive than biologic-experienced patients remained persistent. Biologic-naive patients had a greater mean time to nonpersistence compared with biologic-experienced patients: 32 vs 23 months (p = 0.0002). Moderate and high disease activities based on clinical disease activity index and disease duration were associated with persistence in both biologic-naive and biologic-experienced patients. Additionally, in the biologic-experienced patients, the number of prior medications and skin disease were associated with persistence. The majority of patients with PsA in this study were persistent with their TNFi therapy; biologic-naive patients had greater persistence compared with biologic-experienced patients. Predictors of persistence differed slightly between biologic-naive and biologic-experienced patients
‘Cats give funerals to rats’: making the dead modern with lament
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106846/1/jrai12100.pd
Curricula models and resources along the data continuum: Lessons learned in the development and delivery of research data management and data science education
There continues to be a critical demand for data managers, data curators, and data scientists. This panel addresses the education that needs to be delivered to help students and practicing professionals fill these roles, explores the existing resources available to educators, and provides an interactive environment to discuss the issues. The Institute of Museum and Library Services recognized the need for LIS educators to create the conduit to advance the entire research enterprise by building capacity in data management and data science. They funded projects to develop curricular models and related materials to educate the next generation of information professionals including: LIS Education and Data Science for the National Digital Platform (1); Development of an Enhanced and Expanded Data Management Training Clearinghouse for Earth Science Information Partners (ESIP) (2); User Experience and Assessment (3), Data Curation Education in Research Centers (4), and Geographic Information Librarianship (5). Attendees will learn about existing training materials and will be encouraged to brainstorm how to infuse and integrate research data management and data science into existing LIS programs and courses. A group discussion will consider the following questions: What research data management and data science education exists in other programs? How do we get LIS students more engaged in these data careers? Do other materials exist that could be included in the ESIP Clearinghouse? What can be learned from the ESIP example? (1)RE-70-17-0094-17; (2) LG-70-18-0092-18; (3) RE-20-16-0036-16; (4) RE-02-10-0004-10; (5) RE-05-12-0052-1
Chemical evolution of turbulent protoplanetary disks and the Solar nebula
This is the second paper in a series where we study the influence of
transport processes on the chemical evolution of protoplanetary disks. Our
analysis is based on a flared alpha-model of the DM Tau system, coupled to a
large gas-grain chemical network. To account for production of complex
molecules, the chemical network is supplied with an extended set of surface
reactions and photo-processes in ice mantles. Our disk model covers a wide
range of radii, 10-800 AU (from a Jovian planet-forming zone to the outer disk
edge). Turbulent transport of gases and ices is implicitly modeled in full 2D
along with the time-dependent chemistry. Two regimes are considered, with high
and low efficiency of turbulent mixing. The results of the chemical model with
suppressed turbulent diffusion are close to those from the laminar model, but
not completely. A simple analysis for the laminar chemical model to highlight
potential sensitivity of a molecule to transport processes is performed. It is
shown that the higher the ratio of the characteristic chemical timescale to the
turbulent transport timescale for a given molecule, the higher the probability
that its column density will be affected by diffusion. We find that turbulent
transport enhances abundances and column densities of many gas-phase species
and ices, particularly, complex ones. For such species a chemical steady-state
is not reached due to long timescales associated with evaporation and surface
photoprocessing and recombination. In contrast, simple radicals and molecular
ions, which chemical evolution is fast and proceeds solely in the gas phase,
are not much affected by dynamics. All molecules are divided into three groups
according to the sensitivity of their column densities to the turbulent
diffusion. [Abridged]Comment: 42 pages, 13 figures, 16 tables, accepted for publication in ApJS
Recommended from our members
Identification and Characterization of Small Molecule Inhibitors of a Class I Histone Deacetylase from Plasmodium falciparum
A library of approximately 2000 small molecules biased toward inhibition of histone deacetylases was assayed for antimalarial activity in a high-throughput P. falciparum viability assay. Active compounds were cross-analyzed for induction of histone hyperacetylation in a human myeloma cell line to identify HDAC inhibitors with selectivity for P. falciparum over the human host. To verify on-target selectivity, pfHDAC-1 was expressed and purified and a biochemical assay for pfHDAC-1 activity was established.Chemistry and Chemical Biolog
Response of iron overload to deferasirox in rare transfusion-dependent anaemias: equivalent effects on serum ferritin and labile plasma iron for haemolytic or production anaemias
Objectives: It is widely assumed that, at matched transfusional iron-loading rates, responses to chelation therapy are similar, irrespective of the underlying condition. However, data are limited for rare transfusion-dependent anaemias, and it remains to be elucidated if response differs, depending on whether the anaemia has a primary haemolytic or production mechanism. Methods: The efficacy and safety of deferasirox (Exjade (R)) in rare transfusion-dependent anaemias were evaluated over 1 yr, with change in serum ferritin as the primary efficacy endpoint. Initial deferasirox doses were 10-30 mg/kg/d, depending on transfusion requirements; 34 patients had production anaemias, and 23 had haemolytic anaemias. Results: Patients with production anaemias or haemolytic anaemias had comparable transfusional iron-loading rates (0.31 vs. 0.30 mL red blood cells/kg/d), mean deferasirox dosing (19.3 vs. 19.0 mg/kg/d) and baseline median serum ferritin (2926 vs. 2682 ng/mL). Baseline labile plasma iron (LPI) levels correlated significantly with the transfusional iron-loading rates and with serum ferritin levels in both cohorts. Reductions in median serum ferritin levels were initially faster in the production than the haemolytic anaemias, but at 1 yr, similar significant reductions of 940 and 617 ng/mL were attained, respectively (-26.0% overall). Mean LPI decreased significantly in patients with production (P < 0.0001) and haemolytic (P = 0.037) anaemias after the first dose and was maintained at normal mean levels (< 0.4 mu m) subsequently. The most common drug-related, investigator-assessed adverse events were diarrhoea (n = 16) and nausea (n = 12). Conclusions: At matched transfusional iron-loading rates, the responses of rare transfusion-dependent anaemias to deferasirox are similar at 1 yr, irrespective of the underlying pathogenic mechanism
- …