On statistical interpretations of the semilogarithmic loss function, Mimeo

Abstract This paper corrects and remarks on statistical interpretations of the semilogarithmic loss function introduced for solving positive inverse problems. In this paper, we modify the original statistical model such that the minimization of the semilogarithmic loss function matches the maximum likelihood method. To the best of the authors' knowledge, the induced error distributions from the semilogarithmic loss function are novel. Another correction to the original paper regarding variable transformation is also included

A preliminary study of Ricinus communis survivorship at Ballona Wetlands and Temescal Canyon, Los Angeles, California

Invasive plants such as Castor bean (Ricinus communis) are known to threaten ecosystems due to their competition for resources. The Ballona Wetlands and Temescal Canyon managers employ different techniques to manage the spread of R. communis, potentially resulting in differences in plant survivorship. To investigate this possibility, height of the stems of individual R. communis plants at each site were recorded in order to assign them to cohort groups. Based on the hypothesis predicted that R. communis would have a similar cohort structure at both sites but would exhibit higher survivorship at Temescal Canyon, where R. communis are removed less frequently than at the Ballona Wetlands. However, results indicate that management does not affect cohort structure or stability at either site, but rather, it may have contributed to the significantly higher overall survivorship of R. communis at Temescal Canyon

Oral Health Disparities and Periodontal Disease in Asian and Pacific Island Populations

Introduction—While oral health disparities exist in many ethnic groups in Hawaii, the challenge of developing research and intervention programs is hampered by the lack of a dental school and adequate state resources. Objective—To use a collaboration model to establish a mentoring relationship with a researchintensive school of dentistry to reduce oral health disparities in Hawaii. Methods—Collaborative interactions with the University of Hawaii School of Medicine (UH) and the University of North Carolina School of Dentistry at Chapel Hill (UNC) included bimonthly teleconferences, on-site planning and mentoring sessions, yearly conferences in Hawaii open to the community using UNC faculty, and on-site skills training sessions. The community was asked to participate in determining priorities for research through focus-group interactions. Two pilot investigations were also conducted. Results—Both universities have been awarded grants to fund activities to support the combined intellectual and physical resources of multiple private, public, and community organizations to achieve the goal of improving the oral health status of the people of Hawaii. As a result of initial planning, two related grants have been submitted (one approved, one disapproved) to fund pilot studies on the oral health status of mothers and their babies in a rural community. These studies include both UH and UNC investigators. Conclusions—Health disparities occur among diverse ethnic groups in Hawaii, and links between general health and oral health continue to emerge. In spite of obstacles to designing effective research and intervention programs in Hawaii, UH fostered a collaborative relationship with a premiere dental research institution to develop competence in clinical research, conduct pilot studies, and obtain extramural funding for comprehensive studies. Direct involvement of community representatives in the research process is integral to the success of such studies and will continue to serve as the foundation of our community-based participatory research. The network partners have accomplished their primary goal of developing culturally appropriate methods for assessing determinants of oral health, oral health-related quality of life, and health outcomes in Asians and Pacific Islanders

Reducing disease burden and health inequalities arising from chronic disease among Indigenous children: an early childhood caries intervention

Background: This study seeks to determine if implementing a culturally-appropriate early childhood caries (ECC) intervention reduces dental disease burden and oral health inequalities among Indigenous children living in South Australia, Australia. Methods/Design: This paper describes the study protocol for a randomised controlled trial conducted among Indigenous children living in South Australia with an anticipated sample of 400. The ECC intervention consists of four components: (1) provision of dental care; (2) fluoride varnish application to the teeth of children; (3) motivational interviewing and (4) anticipatory guidance. Participants are randomly assigned to two intervention groups, immediate (n = 200) or delayed (n = 200). Provision of dental care (1) occurs during pregnancy in the immediate intervention group or when children are 24-months in the delayed intervention group. Interventions (2), (3) and (4) occur when children are 6-, 12- and 18-months in the immediate intervention group or 24-, 30- and 36-months in the delayed intervention group. Hence, all participants receive the ECC intervention, though it is delayed 24 months for participants who are randomised to the control-delayed arm. In both groups, self-reported data will be collected at baseline (pregnancy) and when children are 24- and 36-months; and child clinical oral health status will be determined during standardised examinations conducted at 24- and 36-months by two calibrated dental professionals. Discussion: Expected outcomes will address whether exposure to a culturally-appropriate ECC intervention is effective in reducing dental disease burden and oral health inequalities among Indigenous children living in South Australia.Jessica Merrick, Alwin Chong, Eleanor Parker, Kaye Roberts-Thomson, Gary Misan, John Spencer, John Broughton, Herenia Lawrence and Lisa Jamieso

Developmental delays and dental caries in low-income preschoolers in the USA: a pilot cross-sectional study and preliminary explanatory model

Abstract Background Anecdotal evidence suggests that low-income preschoolers with developmental delays are at increased risk for dental caries and poor oral health, but there are no published studies based on empirical data. The purpose of this pilot study was two-fold: to examine the relationship between developmental delays and dental caries in low-income preschoolers and to present a preliminary explanatory model on the determinants of caries for enrollees in Head Start, a U.S. school readiness program for low-income preschool-aged children. Methods Data were collected on preschoolers ages 3–5 years at two Head Start centers in Washington, USA (N = 115). The predictor variable was developmental delay status (no/yes). The outcome variable was the prevalence of decayed, missing, and filled surfaces (dmfs) on primary teeth. We used multiple variable Poisson regression models to test the hypothesis that within a population of low-income preschoolers, those with developmental delays would have increased dmfs prevalence than those without developmental delays. Results Seventeen percent of preschoolers had a developmental delay and 51.3% of preschoolers had ≥1 dmfs. Preschoolers with developmental delays had a dmfs prevalence ratio that was 1.26 times as high as preschoolers without developmental delays (95% CI: 1.01, 1.58; P < .04). Other factors associated with increased dmfs prevalence ratios included: not having a dental home (P = .01); low caregiver education (P < .001); and living in a non-fluoridated community (P < .001). Conclusions Our pilot data suggest that developmental delays among low-income preschoolers are associated with increased primary tooth dmfs. Additional research is needed to further examine this relationship. Future interventions and policies should focus on caries prevention strategies within settings like Head Start classrooms that serve low-income preschool-aged children with additional targeted home- and community-based interventions for those with developmental delays