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Background: Research groups are social locations where teaching and learning merge among students and a principal investigator (PI). When joining, some students are able to contribute to groundbreaking research that addresses complex problems, under the direction of their PI. However, there are accounts of students having a wide range of negative experiences, often at the hands of the PI. Despite the important roles that PIs play in the supervision of students, there is no standardized or required training for researchers holding these roles. As a result, some may replicate the practices they experienced—both positive and problematic. More knowledge is needed regarding group supervision for those in PI roles. Purpose: This autoethnographic longitudinal study explores students’ experiences with and perceptions of PI supervision. The findings from this study offer insights into the design of group practices for current PIs and emerging researchers interested in serving as group PIs. Research Design: To better understand the culture of our own research group, and thus students’ experiences with and perceptions of the PI’s role in supervision, this study included 23 student group members in 12 focus group interviews over four years. Basic qualitative analysis techniques were used to document, identify, and examine our group’s nuanced cultural practices and norms. Findings: Findings reveal balanced perspectives on four PI practices: (1) communicating clearly and validating group members works best in person; (2) providing transparency and reducing uncertainty is desired; (3) inclusive group composition is created through intentional recruitment practices; and (4) group size and member transitions need to be managed to maintain stability. Taken together, student group members believed these PI practices to be both beneficial and challenging to the group’s learning, cohesion, and productivity. The findings also show that group members’ desires and expectations may at times be in conflict. Conclusions: Being a PI offers a unique opportunity to develop new approaches that benefit a group’s research and the learning of all of its members. Learning from students’ experiences with and perceptions of their PI in this study, we hope that current and future group PIs will consider how they compose practices for their groups and support student members through research. Creating new approaches to group supervision may create healthier models for current and future researchers to implement in their own research practices.

The immunogenicity of a T cell Ag is correlated with the ability of its antigenic epitope to bind HLA and be stably presented to T cells. This presents a challenge for the development of effective cancer immunotherapies, as many self-derived tumor-associated epitopes elicit weak T cell responses, in part due to weak binding affinity to HLA. Traditional methods to increase peptide–HLA binding affinity involve modifying the peptide to reflect HLA allele binding preferences. Using a different approach, we sought to analyze whether the immunogenicity of wild-type peptides could be altered through modification of the HLA binding pocket. After analyzing HLA class I peptide binding pocket alignments, we identified an alanine 81 to leucine (A81L) modification within the F binding pocket of HLA-A*24:02 that was found to heighten the ability of artificial APCs to retain and present HLA-A*24:02–restricted peptides, resulting in increased T cell responses while retaining Ag specificity. This modification led to increased peptide exchange efficiencies for enhanced detection of low-avidity T cells and, when expressed on artificial APCs, resulted in greater expansion of Ag-specific T cells from melanoma-derived tumor-infiltrating lymphocytes. Our study provides an example of how modifications to the HLA binding pocket can enhance wild-type cognate peptide presentation to heighten T cell activation.

Within scientific teams, a culture of community (the facilitation of shared values, goals, and an environment where individuals feel valued and want to engage in a team’s work) has implications for members’ learning and participation, and the team’s functioning, cohesion, and productivity. Drawing on 12 focus group interviews conducted over four years with 23 participants, we used an autoethnographic approach to examine how a research team developed a positive culture of community that influences its cohesion and productivity. We present six interconnected cultural practices that can foster a culture of community in settings where team-based learning and collaborations are required.

Background:Graduate education provides students with specialized skills needed to advance science and discovery and prepares future educators and role models for future generations of learners. Given the importance of graduate education, the estimate that more than half of the students who begin it do not complete their degrees is troubling. Existing scholarship suggests that this substantial attrition from graduate school is in part due to inadequate advising. To address this concern, it is important to examine students’ experiences with graduate advising.Purpose:This article presents a new model—the Model of Wholeness in Graduate Advising (MWGA)—that characterizes a range of students’ advising experiences. In so doing, it encourages faculty to move toward a more caring and wholeness-promoting framework in graduate advising.Research Design:To better understand the complexities of graduate advising and the various types of experiences—and relationships—that students have, desire, expect, and need to thrive both professionally and personally, this study included interviews with 42 Black male graduate students attending historically and predominantly White institutions (HPWIs). Thematic analysis revealed that students’ advising experiences included aspects of “ethics of care” (or degrees of care: whole, partial, empty). Iterative analysis of data led to the creation of the practice-informing model: the Model of Wholeness in Graduate Advising (MWGA).Findings:Although some students described experiencing positive interactions and teachable moments with their advisors, others painted pictures of demoralizing encounters and public shaming practices. Still others described advising experiences they did not have but would want. Accounting for this range, the MWGA denotes an upwardly moving relationship between degrees of care (i.e., empty, partial, whole) and students’ perceptions of their advising experiences and relationships (i.e., weak, basic, strong) in part shaped by students’ expectations for their advising experiences and relationships, and their lived experiences.Conclusions and Recommendations:The findings from this study, represented in the MWGA, illustrate theoretical linkages between students’ expectations of advising, the levels of their advising experiences and relationships, and degrees of care demonstrated by their advisors. Most notably, more elements of care tend to result in better lived advising experiences and relationships. For current and future faculty, moving toward a more caring and wholeness-promoting framework might start with recognizing the needs of students as whole people. Creating more caring advising experiences and developing more caring relationships may better assist students in progressing through degree completion, and doing so more fully whole.

Evidence is seen for young, fresh surfaces among Near-Earth and Main-Belt asteroids even though space-weathering timescales are shorter than the age of the surfaces. A number of mechanisms have been proposed to refresh asteroid surfaces on short timescales, such as planetary encounters, YORP spinup, thermal degradation, and collisions. Additionally, other factors such as grain size effects have been proposed to explain the existence of these "fresh-looking" spectra. To investigate the role each of these mechanisms may play, we collected a sample of visible and near-infrared spectra of 477 near-Earth and Mars Crosser asteroids with similar sizes and compositions - all with absolute magnitude H > 16 and within the S-complex and having olivine to pyroxene (ol/(ol+opx)) ratios > 0.65. We taxonomically classify these objects in the Q (fresh) and S (weathered) classes. We find four trends in the Q/S ratio: 1) previous work demonstrated the Q/S ratio increases at smaller sizes down to H, Accepted for publication in Icarus. 14 pages, 4 figures

Background A growing body of research highlights the experiences of Black men students who successfully navigate science, technology, engineering, and mathematics (STEM) educational pathways. Many Black men graduate students in engineering describe moments when their advisors, peers, and, at times, community members make them feel different because of their race and gender. Needed is a better understanding of what motivates Black men to persist in graduate school despite such challenges. Purpose This study advances a new theoretical model, “Black Men's Graduate Engineering Motivation” (BMGEM), to describe the overlaying factors and sources of motivation—and their interrelations—that influence Black men in engineering graduate programs to persist. Research Design To explore the motivational factors that influence Black men in graduate engineering programs at predominantly White institutions (PWIs) to persist, this study of 42 students used an eight-item demographic form, one-on-one semi-structured interviews, and follow-up focus groups. Data analysis was conducted using adapted grounded theory techniques. After the completion of data collection and multiple iterations of analyses (both inductive and deductive), existing conceptualizations of motivation were used to help make sense of data. The connection to existing literature, code development, their placement into categories, and placing categories into themes led to the creation of a substantive, practice-informing theory: Black Men's Graduate Engineering Motivation. Findings Data analysis resulted in the theory of Black Men's Graduate Engineering Motivation (BMGEM). The BMGEM explains the overlaying factors that influence individuals’ experiences and motivations to persist (i.e., sociocultural factors, personal factors, social identities, pre-graduate school experiences), and external and internal motivational sources that also influence students’ motivations to persist (i.e., desire to earn a graduate degree, desire to become an engineer, challenges during graduate school, peers, family members, [under]representation, self-coaching practices, career and professional goals). Conclusions and Recommendations The findings from this study inform future research, and practice-based strategies around broadening participation, that aid in Black men's progress through science and engineering pathways. With this new information, we charge engineering colleges to make true commitments to broadening participation, which means centering students—in this case, Black men—as contributors to STEM. In doing so, engineering colleges need to commit to helping Black men succeed. Assisting in their motivation to persist is a key to meeting this charge.

We identify spectral similarities between asteroids and meteorites. We identify spectral matches between 500 asteroid spectra and over 1,000 samples of RELAB meteorite spectra over 0.45-2.5 microns. We reproduce many major and previously known meteorite-asteroid connections and find possible new, more rare or less-established connections. Well-established connections include: ordinary chondrites (OC) with S-complex asteroids; pristine CM carbonaceous chondrites with Ch-type asteroids and heated CMs with C-type asteroids; HED meteorites with V-types; enstatite chondrites with Xc-type asteroids; CV meteorites with K-type asteroids; Brachinites, Pallasites and R chondrites with olivine-dominated A-type asteroids. We find a trend from Q, Sq, S, Sr to Sv correlates with LL to H, with Q-types matching predominately to L and LL ordinary chondrites, and Sr and Sv matching predominantly with L and H ordinary chondrites. Ordinary chondrite samples that match to the X-complex, all measurements of slabs and many labeled as dark or black (shocked) OCs. We find carbonaceous chondrite samples having spectral slopes large enough to match D-type asteroid spectra. In many cases the asteroid type to meteorite type links are not unique. While there are well established matches between an asteroid class and meteorite class, there are less common but still spectrally compatible matches between many asteroid types and meteorite types. This result emphasizes the diversity of asteroid and meteorite compositions and highlights the degeneracy of classification by spectral features alone. Recent and upcoming spacecraft missions will shed light on the compositions of many of the asteroid classes, particularly those without diagnostic features, (C-, B-, X-, and D-types), with measurements of Ceres, Ryugu, Bennu, Psyche, and C-, P-, and D-types as part of the Lucy mission., Comment: Accepted for publication in Icarus. 38 pages, 8 figures

Immunotherapy has established itself as a stalwart arm in patient care and with precision medicine forms the new paradigm in cancer treatment. T cells are an important group of immune cells capable of potent cancer immune surveillance and immunity. The advent of bioinformatics, particularly more recent advances incorporating algorithms employing machine learning, provide a seemingly limitless ability for T cell analysis and hypothesis generation. Such endeavors have become indispensable to research efforts accelerating and evolving to such an extent that there exists an appreciable gap between knowledge and proof of function and application. Exciting new technologies such as DNA barcoding, cytometry by time-of-flight (CyTOF), and peptide-exchangeable pHLA multimers inclusive of rare and difficult HLA alleles offer high-throughput cell-by-cell analytical capabilities. These outstanding recent contributions to T cell research will help close this gap and potentially bring practical benefit to patients.

HLA-restricted T cell responses can induce antitumor effects in cancer patients. Previous human T cell research has largely focused on the few HLA alleles prevalent in a subset of ethnic groups. Here, using a panel of newly developed peptide-exchangeable peptide/HLA multimers and artificial antigen-presenting cells for 25 different class I alleles and greater than 800 peptides, we systematically and comprehensively mapped shared antigenic epitopes recognized by tumor-infiltrating T lymphocytes (TILs) from eight melanoma patients for all their class I alleles. We were able to determine the specificity, on average, of 12.2% of the TILs recognizing a mean of 3.1 shared antigen-derived epitopes across HLA-A, B, and C. Furthermore, we isolated a number of cognate T cell receptor genes with tumor reactivity. Our novel strategy allows for a more complete examination of the immune response and development of novel cancer immunotherapy not limited by HLA allele prevalence or tumor mutation burden., eLife digest The immune system is the body’s way of defending itself, offering protection against diseases such as cancer. But to remove the cancer cells, the immune system must be able to identify them as different from the rest of the body. All cells break down proteins into shorter fragments, known as peptides, that are displayed on the cell surface by a protein called human leukocyte antigen, HLA for short. Cancer cells display distinctive peptides on their surface as they generate different proteins to those of healthy cells. Immune cells called T cells use these abnormal peptides to identify the cancer so that it can be destroyed. Sometimes T cells can lack the right equipment to detect abnormal peptides, allowing cancer cells to hide from the immune system. However, T cells can be trained through a treatment called immunotherapy, which provides T cells with new tools so that they can spot the peptides displayed by HLA on the previously ‘hidden’ cancer cells. There are many different forms of HLA, each of which can display different peptides. Current research in immunotherapy commonly targets only a subset of HLA forms, and not all cancer patients have these types. This means that immunotherapy research is only likely to be of most benefit to a limited number of patients. Immunotherapy could be made effective for more people if new cancer peptides that are displayed by the other ‘under-represented’ forms of HLA were identified. Murata, Nakatsugawa et al. have now used T cells that were taken from tumors in eight patients with melanoma, which is a type of skin cancer. A library of fluorescent HLA-peptides was generated – using a new, simplified methodology – with 25 forms of HLA that displayed over 800 peptides. T cells were then mixed with the library to identify which HLA-peptides they can target. As a result, Murata, Nakatsugawa et al. found the cancer targets of around 12% of the tumor-infiltrating T cells tested, including those from under-represented forms of HLA. Consequently, these findings could be used to develop new immunotherapies that can treat more patients.

Although there is empirical evidence concerning the value of historically Black colleges and universities (HBCUs), broader narratives about these institutions too often overemphasize challenges and depict them from a deficit perspective. We argue that such depictions elide the benefits of HBCUs within the higher education landscape and are rooted in a form of institutional anti-blackness—persistent imagery and discourse that construct Black colleges and universities as institutions devoid of value. In response to such silencing, this study employs counter-narratives rooted in a critical race methodology to illuminate the modern contributions of HBCUs as told by their chief executive officers—HBCU presidents. These contributions include transforming today’s learners into tomorrow’s leaders, a commitment to serving low-income students that is unencumbered by their financial strains, and tapping the potential of students who were marginalized in prior academic environments.

This article advances the Theoretical Model of Engineering Professorial Intentions to explain why individuals do or do not choose to pursue faculty careers. A 13-month ethnographic study of members of a diverse chemical engineering research group was conducted. The resulting theoretical model accounts for six emergent components that contribute to members’ identification with faculty careers: (1) social identities and personal factors; (2) sociocultural factors; (3) participation, interactions, and learning in research group experiences; (4) faculty prototype; (5) social comparisons; and (6) individual and institutional experiences. The article concludes with implications for further research and recommendations regarding mentoring and design of research group experiences that may promote greater interest in and identification with the professoriate.

While much is known about how Black students negotiate and navigate undergraduate studies, there is a dearth of research on what happens when these students enter graduate school. This article presents the results of a study of 21 Black male graduate students in engineering from one highly ranked research-intensive institution. This article provides evidence of structurally racialized policies within the engineering college (e.g., admissions) and racialized and gendered interactions with peers and advisors that threaten Black males’ persistence in engineering. We argue for taking an anti-deficit approach to understanding Black males’ persistence in engineering. We conclude with implications for policy, practice, and research that could further improve the scholarship and experiences of Black males in engineering graduate programs.

Purpose Professionals in higher education are expected to be informed consumers of knowledge who seek out scholarship, critical evaluators of the applicability of extant knowledge, and contributors who build new knowledge for higher education practice. Despite the understood importance of developing research competencies, many have limited opportunities to develop these skills. This study aims to explore one way individuals develop research competencies: through participation in team-based research experiences. Design/methodology/approach A longitudinal case study approach was used to investigate what participants in an education research group learn, and how their participation in the group changes the ways in which they think about themselves as researchers and scholars. Four group members participated in two focus group interviews (at the end of the fall 2015 and spring 2016 academic semesters). Interviews were analyzed using thematic analysis. Findings Study participants report gaining knowledge about research, developing an identity as a researcher, and learning about faculty roles. Particular group practices and activities (e.g. full group meetings, subgroup meetings, professional development moments) helped mediate members’ learning and identity development. Originality/value Research groups should be considered valuable contexts where teaching and learning take place. By learning – and integrating what we learn – from research group participation, the higher education and student affairs fields may become better able to generate innovative practices and activities that provide students and professionals with opportunities to develop important research competencies.

Despite a growing body of work on the experiences of Black collegians, the higher education knowledge base lacks scholarship focused on Black men in graduate programs who are foreign-born and/or identify ethnically as other than African American. In this article, we provide a domain-specific investigation (i.e., based on students’ field of study), centering on nine Black men in engineering graduate programs. Three themes emerged regarding students’ racialized experiences and effects of racialization: (1) racialization as a transitional process; (2) cultural identity (dis)integrity; and (3) racialized imposter syndrome. We conclude with implications for developing and implementing promising practices and activities that aid students throughout graduate school. Such targeted efforts might also improve the likelihood of students remaining in the engineering workforce. Keywords: Black males, foreign-born, graduate students, engineering, racialized experiences, ISSN: 2162-3104 Print/ ISSN: 2166-3750 Online Volume 7, Issue 4 (2017), pp. 925-943 © Journal of International Students http://jistudents.org/ doi: 10.5281/zenodo.1029487

Purpose In some fields, research group experiences gained in laboratories are more influential than the classroom in shaping graduate students’ research abilities, understandings of post-graduate careers and professional identities. However, little is known about what and how students learn from their research group experiences. This paper aims to explore the learning experiences of engineering graduate students in one chemical engineering research group to determine what students learned and to identify the practices and activities that facilitated their learning. Design/methodology/approach Ethnography was used to observe the experiences of one research group in chemical engineering. Fieldwork included 13 months of observations, 31 formal interviews (16 first-round and 15 second-round interviews) and informal interviews. Fieldnotes and transcriptions were analyzed using grounded theory techniques. Findings Research group members developed four dominant competencies: presenting research, receiving and responding to feedback, solving problems and troubleshooting problems. Students’ learning was facilitated by the practices and activities of the research group (e.g. weekly full group and subgroup meetings) and mediated through the interactions of others (i.e. peers, faculty supervisor and lab manager). Originality/value This study adds to the engineering education literature and contributes to the larger discourse on identifying promising practices and activities that improve student learning in graduate education.

Peptide-major histocompatibility complex (pMHC) multimers enable the detection of antigen-specific T cells in studies ranging from vaccine efficacy to cancer immunotherapy. However, this technology is unreliable when applied to pMHC class II for the detection of CD4

PurposeThis study aims to better understand how students’ academic strains and multilevel strengths relate to their math achievement, with a particular emphasis on underrepresented students of color and girls given the need to broaden science, technology, engineering and math (STEM) participation for these groups.Design/methodology/approachNational Education Longitudinal Study of 1988 data was used for a historical examination of the various student academic strains and multilevel strengths that relate to math achievement in high school. T-tests and chi-square tests were conducted to examine differences in strains and strengths across policy-relevant student subgroups. Ordinary least squares (OLS) regression was used to examine how students’ strains and strengths related to their math achievement and the relative importance of each of these factors.FindingsThe findings suggest that both the academic strains and multilevel strengths that students’ experience in middle school are related to their high school math achievement and the prevalence of these factors varies across different policy-relevant student subgroups. Furthermore, the relative importance of these factors on achievement differs.Originality/valueStudies which focus on either students’ academic challenges or their adaptive strengths fall short of a more nuanced discussion about how both factors relate to math outcomes. This study addresses this limitation and emphasizes that stakeholders who are interested in STEM diversity should consider holistic strategies for alleviating gender and racial/ethnic discrepancies in secondary math achievement.

BACKGROUND Ethics instruction is an important component of engineering undergraduate education, but little research has identified aspects of the undergraduate experience that contribute most to students' eth- ical development. Thus, an assessment of the impact of students' experiences on their ethical devel- opment is warranted. DESIGN/METHOD Using survey data collected from nearly 4,000 engineering undergraduates at 18 institutions across the U.S., we present descriptive statistics related to students' formal curricular experiences and their co-curricular experiences. Additionally, we present data for three constructs of ethical development (knowledge of ethics, ethical reasoning, and ethical behavior). RESULTS For our sample, the quantity and quality of students' formal curricular experiences and their co-cur- ricular experiences related to ethics was high. The levels of ethical knowledge and reasoning varied, as did ethical behavior. CONCLUSIONS Our data highlight opportunities for improving the engineering undergraduate/bachelor's level curri- cula in order to have a greater impact on students' ethical development. We suggest that institutions integrate ethics instruction throughout the formal curriculum, support use of varied approaches that foster high-quality experiences, and leverage both influences of co-curricular experiences and stu- dents' desires to engage in positive ethical behaviors.

excluded AAPI, Latinos, and Native Americans from discussions related to improving the educational experiences of men of color (Perez II, 2014; Teranishi, 2010; Torres & Bitsoi, 2011). This book offers a persuasive critique of deficit-oriented paradigms that often guide interventions intended to increase the success of students of color in higher education. Men of Color in Higher Education is a must-read for researchers and educators committed to fostering the success of AAPI, Black, Latino, and Native American men. Although some readers may contend that this book essentializes the experiences of men of color, I disagree. The contributors make a compelling case for understanding and addressing the detrimental effects of patriarchal masculinity on communities of color. The feminist perspectives infused throughout this text, provide readers with the knowledge needed to recognize and deconstruct patriarchy. Additionally, readers have much to gain from integrating anti-deficit perspectives into research, policies, and practices to increase the success of men of color. A concluding chapter that outlines implications for policy and practice would broaden the scope of this publication. Learning to recognize and capitalize on the assets men of color bring with them to higher education advances the agenda of this book. Future editions of this scholarly text could focus exclusively on women of color as well as AAPI, Latino, and Native American men in higher education.

The pervasiveness of health disparities by socioeconomic status (SES) in the United States has been documented for years.1–6 Regardless of race or ethnicity, health outcomes for individuals of lower SES continue to be poorer than those of their higher-SES counterparts.3,7 This is also true for periodontal health: for years, the data have shown significant SES differences across racial/ethnic groups.8–18 Many previous studies documenting differences in periodontal health have included SES indicators (i.e., income and education) in their analyses. Some studies have provided cross-tabulations between periodontitis and categories for each SES indicator,19–25 whereas others have included these indicators as covariates in multivariable analysis approaches.22,23,25–29 The first group of studies has reported higher prevalences and severity of periodontitis for those with lower SES compared with their higher-SES counterparts. The second group has documented the persistence of racial/ethnic differences after adjusting for SES indicators. However, the incommensurability of these indicators across racial/ethnic groups has not been discussed in these studies. To date, SES indicators have not been investigated as the main independent covariates in studies of periodontal health. Therefore, their contribution to the existing racial/ethnic differences or to the disparity in the prevalence of periodontitis in general remains unknown. To address these issues and expand our previous work on racial/ethnic differences in periodontitis, we ascertained prevalences of periodontitis for (1) income and (2) education among non-Hispanic Black, Mexican-American, and non-Hispanic White adults aged 50 years or older using data from the third National Health and Nutrition Examination Survey (NHANES III). In addition, we investigated the combined effect of income and education on the prevalence of periodontitis. Finally, in this article we discuss the pathways by which SES indicators intertwined with race/ethnicity to affect periodontal health.

Background The authors conducted a study to test the hypothesis that high consumption of soft drinks, relative to milk and 100 percent fruit juice, is a risk factor for dental caries in low-income African-American children in Detroit. Methods Trained dentists and interviewers examined a representative sample of 369 children, aged 3 to 5 years, in 2002–2003 and again two years later. The authors used the 2000 Block Kids Food Frequency Questionnaire (NutritionQuest, Berkeley, Calif.) to collect dietary information. They assessed caries by using the International Caries Detection and Assessment System. Results Soft drinks, 100 percent fruit juice and milk represented the sugared beverages consumed by the cohort. A cluster analysis of the relative proportion of each drink at baseline and follow-up revealed four consumption patterns. Using zero-inflated negative binomial models, the authors found that children who changed from being low consumers of soft drinks at baseline to high consumers after two years had a 1.75 times higher mean number of new decayed, missing and filled tooth surfaces compared with low consumers of soft drinks at both time points. Conclusion Children who consumed more soft drinks, relative to milk and 100 percent fruit juice, as they grew older were at a greater risk of developing dental caries. Clinical Implications Health promotion programs and health care providers should emphasize to patients and caregivers the caries risk associated with consumption of soft drinks.

The relationships between blood lead (PbB) and saliva lead (PbSa) concentrations and the determinants of PbB and PbSa status in 970 low-income adults in the city of Detroit, Michigan were explored. Average PbB and PbSa values in the sample population were found to be 2.7+/-0.1 microg/dl and 2.4+/-0.13 microg/l (equivalent to 0.24+/-0.13 microg/dl), respectively, and a weak but statistically significant association was found between the lead levels in the two types of body fluid samples. The average PbB level for men (4.0+/-0.56 microg/dl) was higher than that for women (2.7+/-0.11 microg/dl); other significant predictors of PbB included age, level of education, being employed, income level, the presence of peeling paint on the wall at home and smoking. There was no gender- or age-dependent difference in blood saliva values but statistically significant correlations were found between PbSa and level of education, employment, income level and smoking. Dental caries was severe in this population. Only 0.5% of the participants had no clinical signs of caries, over 80% had cavitated carious lesions (i.e., lesions that had progressed into dentin), and the number of lost teeth and carious lesions averaged 3.4 and 30, respectively. Weak but significant associations were found between PbB as well as PbSa and measures of dental caries in the study population. The positive associations are believed to be a reflection of the fact that the risk factors for dental caries, especially in low-income populations of the US, overlap extensively with those of lead poisoning and may not have a causal significance.

We analyzed fluid intake data among children aged 2–10 years from a 24-hour dietary recall interview in the NHANES III (1988–94) to investigate the effect of high consumption of carbonated soft drinks on caries in the primary dentition. We used cluster analysis to determine fluid consumption patterns. Four distinct fluid consumption patterns were identified: high carbonated soft drinks, high juice, high milk, and high water. About 13% of children had a high carbonated soft drink consumption pattern; they also had a significantly higher dental caries experience in the primary dentition than did children with other fluid consumption patterns. A fluid intake pattern comprised mainly of milk, water, or juice was less likely to be associated with dental caries. Findings of this study suggest that high consumption of carbonated soft drinks by young children is a risk indicator for dental caries in the primary dentition and should be discouraged.

Background The author compared the caries-inhibitory action of sorbitol- and xylitol-sweetened chewing gum and assessed the role of these products in caries prevention. Types of Studies Reviewed The author reviewed studies including randomized field trials with substantial numbers of participants and observational studies. He did not review case studies. He found studies through a MEDLINE search and by hand searching. Results When compared with sugar-sweetened gum, sorbitol-sweetened gum had low carcinogenicity when it was chewed no more than three times per day. Xylitol-sweetened gum was noncariogenic in all of the protocols tested. Some studies claimed that xylitol-sweetened gum had an anticariogenic effect, though these claims need further study. There also is good evidence that when mothers of infants and young children chew xylitol-sweetened gum, it will block transmission of mutans streptococci from mother to child. Clinical Implications The evidence is strong enough to support the regular use of xylitol-sweetened gum as a way to prevent caries, and it can be promoted as a public-health preventive measure. Chewing xylitol-sweetened gum, especially for patients who like chewing gum, can be fitted readily into a regimen that includes frequent fluoride exposure, good oral hygiene and regular dental appointments.

The aim of this study was toexamine the relationship between dietary patterns and caries experience in a representative group of low-income African-American adults. Participants were residents of Detroit, Michigan, with household incomes below 250% of the federally-established poverty level (n = 1,021). Dietary histories were obtained by trained interviewers in face-to-face interviews with the adult participants, using the Block 98.2® food frequency questionnaire. Caries was measured by the ICDAS criteria (International Caries Detection and Assessment System). There were 200 dietary records whose data were judged to be invalid; these participants were omitted from the dietary analyses to leave n = 821. Factor analysis identified patterns of liquid and solid food consumption, and the resulting factor scores were used as covariates in multivariable linear regression. Caries was extensive, with 82.3% of the 1,021 participants (n = 839) having at least one cavitated lesion. Nearly three quarters of the adult participants were overweight or obese. This population had severe caries, poor oral hygiene, and diets that are high in sugars and fats and low in fruits and vegetables. Apart from tap water, the most frequently consumed food item by adults of all ages was soft drinks; 19% of all energy from sugar came from soft drinks alone. In both the bivariate analyses and in the regression model, frequency of soft drink consumption and the presence of gingival plaque deposits were significantly associated with caries. Interventions to promote oral health are unlikely to be successful without improvements in the social and physical environment.

Trends in periodontal diseases in the USA have been documented for years. However, the results have been mixed, mostly due to different periodontal assessment protocols. This study examined change in the prevalence of periodontitis between the NHANES III and the NHANES 1999–2000, and differences in the prevalence of periodontitis among racial/ethnic groups in the USA. Analysis was limited to non-Hispanic black, non-Hispanic white, and Mexican-American adults aged 18+ yrs in the NHANES III (n = 12,088) or the NHANES 1999–2000 (n = 3214). The prevalences of periodontitis for the NHANES III and the NHANES 1999–2000 were 7.3% and 4.2%, respectively. In multivariable analyses, blacks were 1.88 times (95%CI: 1.42, 2.50) more likely to have periodontitis than whites surveyed in the NHANES III. However, the odds of periodontitis for blacks and Mexican-Americans did not differ from those for whites surveyed in the NHANES 1999–2000. Our findings indicate that the prevalence of periodontitis has decreased between the NHANES III and the NHANES 1999–2000 for all racial/ethnic groups in the USA.

The purpose of this paper is to review the concepts of risk as we use them today in dental public health practice, and to suggest that we should broaden our view of risk. Use of terms like risk factor in the literature can be quite vague, and it is recommended that a clear definition of that and related terms be adhered to. A broader view of risk in dental research would take in the concepts of social determinants of health and population health. While some progress has been made in our understanding of these issues, better knowledge would give the public health administrator more readily available information to use in program planning. The skewed distribution of caries in the high-income countries has led to the emergence of targeted prevention programs toward those considered to be at high risk. In public health programs, targeting at the individual level is not practical: the risk assessment methods are not yet sufficiently precise, and even when individuals are identified there are practical problems with schools and with the children themselves. (For private practice, however, high-risk child patients can be identified as those with at least one approximal lesion in permanent teeth.) For public health purposes, an argument is made for geographic targeting, i.e. identification of areas of social deprivation where whole schools or school districts can be targeted. Geographic targeting is something between individual targeting and whole-population approaches. Ideally, geographic targeting would supplement population measures like water fluoridation and dental health education. Examples of geographic targeting from Ohio and New York are presented as illustrations.

This study used an 11-month break in water fluoridation to identify the time when developing incisors are most sensitive to fluorosis development. The study was based in Durham, NC, where an interruption to water fluoridation occurred between September, 1990, and August, 1991. A total of 1896 children was dentally examined. Fluorosis was measured by the TF index, and parents or guardians completed a questionnaire on demographics and fluoride history. Age cohorts ranged from those born 5 years before the break, to those born 1 year after the resumption of fluoridation. Fluorosis prevalence for seven age cohorts whose birth years ranged from 1985–86 to 1991–92 was 57.1, 62.3, 33.0, 32.3, 39.8, 30.2, and 36.8%, respectively. Children aged from birth to 3 years at the break, and those born 1 year after it, had less fluorosis than those aged 4–5 years at the break.

This systematic review addresses the question: In the modern age of extensive fluoride exposure, do individuals with a high level of sugar intake experience greater caries severity relative to those with a lower level of intake? The MEDLINE and EMBASE databases were searched for English-language papers published between 1980 and 2000 using a search expression developed in conjunction with an experienced librarian. There were 809 papers located in the initial search. A review of titles and abstracts to identify clearly irrelevant papers reduced this number to 134. Two readers each read one half of these papers, and application of predetermined inclusion/exclusion criteria reduced this number of papers to sixty-nine. Criteria were established for scoring the quality of each of these papers on evidence tables. The maximum score for each paper was 100; the sixty-nine papers rated scored between 12 and 79. Final judgment of results was limited to those thirty-six papers that scored 55 or higher on the evidence tables and that reported studies carried out in countries where there is moderate-to-extensive fluoride exposure. Results showed that only two papers found a strong relationship between sugar consumption and caries development, sixteen found a moderate relationship, and eighteen found weak-to-no relationship. It was concluded that the relationship between sugar consumption and caries is much weaker in the modern age of fluoride exposure than it used to be. Controlling the consumption of sugar remains a justifiable part of caries prevention, however, if not always the most important aspect.

Low birthweight is a major public health and social problem in the United States. While a long list of mortality and morbidity conditions have been associated with low birthweight, dental conditions have not received much attention. This systematic review addresses this question: Do low-birthweight children (birthweight

Objective: Recommended fluoride concentrations in US public water systems are between 0.7–1.2 ppm, depending on the mean daily maximum temperature. This range assumes that water intake is higher in warmer than in cooler climates, based on research from the 1950s. The aim of this analysis is to relate fluid consumption among American children aged 1–10 years to the local climate under modern conditions. Methods: The quantities of daily total fluid intake per body weight (ml/kg) and plain water intake per body weight (ml/kg) of children were calculated from the 24-hour recall diet survey in the third National Health and Nutrition Examination Survey (NHANES III, 1988–94). The mean daily maximum temperature from 1961 to 1990, averaged for the month during which the NHANES III exam was conducted, was obtained for each survey location from the US Local Climate Historical Database. Multiple regression analysis was conducted using SAS and SUDAAN. Results: Fluid intake was significantly associated with age, sex, socioeconomic status (SES), and race and ethnicity. No significant association could be found between the amount of either total fluid or plain water intake and mean daily maximum temperature, either before and after controlling for sex, age, SES, and race or ethnicity. Conclusions: Results indicate that there is no evidence that fluid consumption among children is significantly related to mean temperature in modern conditions. This suggests that the national temperature-related guidelines for fluoride concentration in drinking water may be due for reevaluation.