Gaussian-type lower bounds for the density of solutions of SDEs driven by fractional Brownian motions

In this paper we obtain Gaussian-type lower bounds for the density of solutions to stochastic differential equations (SDEs) driven by a fractional Brownian motion with Hurst parameter $H$. In the one-dimensional case with additive noise, our study encompasses all parameters $H\in(0,1)$, while the multidimensional case is restricted to the case $H>1/2$. We rely on a mix of pathwise methods for stochastic differential equations and stochastic analysis tools.Comment: Published at http://dx.doi.org/10.1214/14-AOP977 in the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org

Instructional Math Technology in Secondary Special Education: Teacher-Reported Practices and Perceptions

Students with disabilities often have difficulty meeting established math proficiency levels. Without these skills, students may face increased challenges in transitioning to adulthood, including fewer post-secondary educational opportunities, limited career options, and decreased long-term income. Addressing low math skills is important to improving options for students with disabilities. Research indicates that technology-based interventions have the potential to improve academic outcomes. The purpose of this study was to examine the math instructional technology used in secondary math classrooms with students with disabilities. The study also examined teacherperceived barriers and desired supports related to the integration of technology. A three-round Delphi method was used to collect survey data from participants. Participants were 36 secondary general and special education teachers who were identified as experts by their school principals and currently teaching secondary math to students with disabilities in co-teach and/or resource settings. Expertise criteria included a standard teaching license, experience using instructional software with students, and a minimum of three years of experience teaching students with disabilities in co-teach and/or resource settings. The results indicated that participants most frequently used ALEKS, Kahoot, ST Math, or no instructional software in math instruction for students with disabilities. Software selection was based on software availability, software features, or no specific selection methods. Participants identified lack of time, cost, and lack of technology as barriers to implementation. The most frequently identified desired supports were training and support, additional technology, and no supports, and participants perceived technology as increasing engagement, improving math outcomes, or having an unknown impact on math performance. These findings have implications for administrators, practitioners, researchers, and teacher preparation program developers. Instructional software continues to be underutilized in secondary math classrooms with students with disabilities, and the instructional software programs that are utilized do not have a strong evidence base. Administrators and practitioners should use a rigorous decision-making process to select and implement evidence-based instructional software to improve the math outcomes of students with disabilities. Administrators should also provide ongoing training to teachers to support technology integration. For researchers, additional focus is needed on replication studies to strengthen the evidence base of instructional software programs. Finally, teacher preparation programs should include coverage of basic technology concepts, educational technology, software evaluation methods, budgeting, and time management

Dengue Vectors and their Spatial Distribution

The distribution of dengue vectors, Ae. aegypti and Ae. albopictus, is affected by climatic factors. In addition, since their life cycles are well adapted to the human environment, environmental changes resulting from human activity such as urbanization exert a great impact on vector distribution. The different responses of Ae. aegypti and Ae albopictus to various environments result in a difference in spatial distribution along north-south and urban-rural gradients, and between the indoors and outdoors. In the north-south gradient, climate associated with survival is an important factor in spatial distribution. In the urban-rural gradient, different distribution reflects a difference in adult niches and is modified by geographic and human factors. The direct response of the two species to the environment around houses is related to different spatial distribution indoors and outdoors. Dengue viruses circulate mainly between human and vector mosquitoes, and the vector presence is a limiting factor of transmission. Therefore, spatial distribution of dengue vectors is a significant concern in the epidemiology of the disease

Use of LANDSAT imagery for soil survey

The author has identified the following significant results. The MSS channels 6 and 7 were considered the best to study the relative tonality of different spectral responses of soils, while channels 5 and 7 were best for natural vegetation, drainage patterns, and land use. Frequency ratio was the recommended index for use when analyzing a drainage pattern quantitatively

The structure of the space of affine Kaehler curvature tensors as a complex module

We use results of Matzeu and Nikcevic to decompose the space of affine Kaehler curvature tensors as a direct sum of irreducible modules in the complex settin

Molecular Biology and Clinical Mitigation of Cancer Treatment-Induced Neuropathy

Disruption of microtubule function is the antitumor mechanism of several classes of drugs used to treat cancer today. However, the significant beneficial effect on tumor outcomes is frequently counterbalanced by neurotoxic complications. Despite an abundance of scientific data, our understanding of the biological mechanisms underlying this toxic reaction remains unclear, further hindering attempts to identify and develop effective preventive strategies. The primary goals of this review are to: (1) provide insight regarding the biology of the microtubule, (2) analyze the molecular and biochemical pathways that may be involved in the development of neurotoxicity, and (3) propose a unifying concept linking drug-induced neuropathy, microtubule dysfunction, and vitamin D

Scalar form factors and nuclear interactions

The scalar-isoscalar term in the two-pion exchange $NN$ potential is abnormally large and does not respect the hierarchy of effects predicted by chiral perturbation theory. We argue that this anomaly is associated with non-perturbative effects, which are also present in the $\pi N$ scalar form factor.Comment: Talk given at the 20EFB, Pisa, Italy, September 2007. 3 pages and 4 figure