1,653 research outputs found
Multi-parameter uncertainty analysis of a bifurcation point
Parameter uncertainty analysis of climate models has become a standard approach for model validation and testing their sensitivity. Here we present a novel approach that allows one to estimate the robustness of a bifurcation point in a multi-parameter space. In this study we investigate a box model of the Indian summer monsoon that exhibits a saddle-node bifurcation against those parameters that govern the heat balance of the system. The bifurcation brings about a change from a wet summer monsoon regime to a regime that is characterised by low precipitation. To analyse the robustness of the bifurcation point itself and its location in parameter space, we perform a multi-parameter uncertainty analysis by applying qualitative, Monte Carlo and deterministic methods that are provided by a multi-run simulation environment. Our results show that the occurrence of the bifurcation point is robust over a wide range of parameter values. The position of the bifurcation, however, is found to be sensitive on these specific parameter choices
Empowering Latino parents to transform the education of their children
This article emphasizes the role of parental involvement in the college preparation of Latino elementary and secondary school students. Although literature shows that education is highly valued in Latino families, actual college enrollment rates for Latino youth are below average. This has been attributed to barriers including lack of financial resources, problems in communication with schools, and low familiarity with the college planning process. The American Dream Academy is a university outreach program that is designed to help Latino families overcome these barriers. We conducted a qualitative analysis of speeches that were prepared and delivered by parents at graduation ceremonies of the program from 2007 to 2009. Our analysis revealed six themes: facing challenges, envisioning success, understanding the school system, taking ownership, community raising a child, and creating a supportive home environment. The findings enrich existing literature and help understand the complex systems that are at play with parental involvement in Latino families
The role of objects and effects in action imitation: Comparing the imitation of object-related actions vs. gestures in 18-month-old infants
An ancestral secretory apparatus in the protozoan parasite Giardia intestinalis
The protozoan parasite Giardia intestinalis belongs to one of the earliest diverged eukaryotic lineages. This is also reflected in a simple intracellular organization, as Giardia lacks common subcellular compartments such as mitochondria, peroxisomes, and apparently also a Golgi apparatus. During encystation, developmentally regulated formation of large secretory compartments containing cyst wall material occurs. Despite the lack of any morphological similarities, these encystation-specific vesicles (ESVs) show several biochemical characteristics of maturing Golgi cisternae. Previous studies suggested that Golgi structure and function are induced only during encystation in Giardia, giving rise to the hypothesis that ESVs, as a Giardia Golgi equivalent, are generated de novo. Alternatively, ESV compartments could be built on the template structure of a cryptic Golgi in trophozoites in response to ER export of cyst wall material during encystation. We addressed this question by defining the molecular framework of the Giardia secretory apparatus using a comparative genomic approach. Analysis of the corresponding transcriptome during growth and encystation revealed surprisingly little stage-specific regulation. A panel of antibodies was generated against selected marker proteins to investigate the developmental dynamics of the endomembrane system. We show evidence that Giardia accommodates the export of large amounts of cyst wall material through re-organization of membrane compartment(s) in trophozoites with biochemical similarities to ESVs. This suggests that ESVs are selectively stabilized Golgi-like compartments in a unique and archetypical secretory system, which arise from a structural template in trophozoites rather than being generated de novo
Monitoring Low Density Avian Populations: An Example using Mountain Plovers
Declines in avian populations highlight a need for rigorous, broad-scale monitoring pro-grams to document trends in avian populations that occur in low densities across expansive landscapes. Accounting for the spatial variation and variation in detection probability inherent to monitoring programs is thought to be effort-intensive and time-consuming. We determined the feasibility of the analytical method developed by Royle and Nichols (2003), which uses presence-absence (detection-non-detection) field data, to estimate abundance of Mountain Plovers (Charadrius montanus) per sampling unit in agricultural fields, grassland, and prairie dog habitat in eastern Colorado. Field methods were easy to implement and results suggest that the analytical method provides valuable insight into population patterning among habitats. Mountain Plover abundance was highest in prairie dog habitat, slightly lower in agricultural fields, and substantially lower in grassland. These results provided valuable insight to focus future research into Mountain Plover ecology and conservation
Stability of complex hyperbolic space under curvature-normalized Ricci flow
Using the maximal regularity theory for quasilinear parabolic systems, we
prove two stability results of complex hyperbolic space under the
curvature-normalized Ricci flow in complex dimensions two and higher. The first
result is on a closed manifold. The second result is on a complete noncompact
manifold. To prove both results, we fully analyze the structure of the
Lichnerowicz Laplacian on complex hyperbolic space. To prove the second result,
we also define suitably weighted little H\"{o}lder spaces on a complete
noncompact manifold and establish their interpolation properties.Comment: Some typos in version 2 are correcte
A novel missense mutation in the gene for gap-junction protein α3 (GJA3) associated with autosomal dominant “nuclear punctate” cataracts linked to chromosome 13q
Interventions for Family Members of Adolescents With Disruptive Behavior Disorders
Problem -
The family members of adolescents diagnosed with disruptive behavior disorders (DBDs) experience profound stress and burden. Despite the need for empirically supported interventions that address the challenges faced by these family members, few such interventions are available.
Methods -
In this qualitative descriptive study, we conducted in-depth interviews with 15 families of adolescents diagnosed with DBD. We asked the family members to identify what types of mental health services they needed and to describe the “ideal” program that would best address their concerns.
Findings -
Family members identified several intervention modalities that would fit their needs, including multifamily groups, family therapy, individual therapy, and community-based hotlines. They indicated that programs should address the following topics: family communication, conflict resolution, education about DBD, and strategies to improve interactions with child service agencies.
Conclusions -
Clinicians should recognize that all family members may need support to manage the stressors associated with caring for or living with adolescents with DBD. When working with families, clinicians should provide information about the etiology and management of DBD, help navigate interactions with child service agencies, and employ strategies to improve family communication and functioning
Management of Motion and Anatomical Variations in Charged Particle Therapy:Past, Present, and Into the Future
The major aim of radiation therapy is to provide curative or palliative treatment to cancerous malignancies while minimizing damage to healthy tissues. Charged particle radiotherapy utilizing carbon ions or protons is uniquely suited for this task due to its ability to achieve highly conformal dose distributions around the tumor volume. For these treatment modalities, uncertainties in the localization of patient anatomy due to inter- and intra-fractional motion present a heightened risk of undesired dose delivery. A diverse range of mitigation strategies have been developed and clinically implemented in various disease sites to monitor and correct for patient motion, but much work remains. This review provides an overview of current clinical practices for inter and intra-fractional motion management in charged particle therapy, including motion control, current imaging and motion tracking modalities, as well as treatment planning and delivery techniques. We also cover progress to date on emerging technologies including particle-based radiography imaging, novel treatment delivery methods such as tumor tracking and FLASH, and artificial intelligence and discuss their potential impact towards improving or increasing the challenge of motion mitigation in charged particle therapy
Erratum: Time-resolved dosimetry for validation of 4D dose calculation in PBS proton therapy (vol 65, 125015, 2020)
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