Young J. Kim

Do fertility intentions affect fertility behavior

This paper examines the relationship between fertility intentions and fertility behavior using the data from the National Survey of Families and Households with a sample of 2812 non-Hispanic Whites. Results demonstrated a strong relationship between fertility intentions and the percentage of having a birth. It was also noted that the effect on fertility is greater when the intentions are held with greater certainty. Furthermore fertility intentions and their certainty predict fertility behavior better among married persons as compared to all other variables in the model. Thus marital status is an important life course variable wherein a change in marital status significantly affects birth probabilities. Finally this study indicated that fertility is a purposive behavior that is based on intentions applied into the life course and changed when unexpected developments occur.

Women's Employment, Marital Happiness, and Divorce

The relationship between womens employment and the risk of divorce is both complex and controversial. The role specialization (or interdependence) view of marriage argues that the gains to marriage for both partners decrease when both are in the labor force, and hence womens employment destabilizes marriage. In contrast, the economic opportunity hypothesis asserts that female labor force participation does not intrinsically weaken marriage, but gives women resources that they can use to leave unsatisfactory marriages. Here we use data from the two waves of the National Survey of Families and Households to conduct the first large-scale empirical test of those conflicting claims. Our results provide clear evidence that, at the individual level, womens employment does not destabilize happy marriages but increases the risk of disruption in unhappy marriages.

Consistency of adolescents' self-report of sexual behavior in a longitudinal study

This study examines three issues relevant to adolescent self-reported sexual behavior: the extent to which adolescents rescind reports of sexual intercourse, changes in reporting of lifetime sexual intercourse, and changes in reported age at first sexual intercourse. Data come from a three-year longitudinal study of health-compromising behaviors among a cohort a 758 rural adolescents. Students completed a self-administered questionnaire on health behaviors annually in eighth, ninth, and tenth grades. Findings show that 88.8% of students in eighth grade and 94.3% in ninth grade who reported having had sexual intercourse gave the same answer in a subsequent year. Approximately 15% of students reported fewer numbers of lifetime sexual intercourse experiences in tenth grade than they did in ninth grade. Age at first sexual intercourse was reported inconsistently by 67% of the students. Inconsistency rates differed by racial-gender groups, question sensitivity, and prior sexual experience.

Intratumoral Administration of TLR4 Agonist Absorbed into a Cellular Vector Improves Antitumor Responses

Purpose: Because toll-like receptor (TLR) agonists have been well characterized as dendritic cell (DC) activators, we hypothesized that the admixture of TLR4 agonist into a cellular vector could improve the antitumor response in vivo. Experimental Design: Granulocyte macrophage colony stimulating factor secreting whole cell tumor cell vector (GVAX) was formulated with lipopolysaccharide (LPS), a TLR4 agonist, and its intratumoral therapeutic efficacy was tested in three different murine models. We utilized immunohistochemistry, fluorescence-activated cell sorting, enzyme-linked immunosorbent spot (ELISPOT), and in vivo CTL analysis to assess both local innate immune responses within the tumor tissue as well as the downstream generation of antitumor T-cell responses. Results: Intratumoral treatment of LPS-absorbed GVAX showed efficacy in improving an antitumor response in vivo in comparison with GVAX alone. Improved antitumor efficacy of this novel admixture was not present in TLR4 signaling impaired mice. In the CT26 model, 40% to 60% of the mice showed regression of the transplanted tumor. When rechallenged with CT26 tumor cells, these mice proved to be immunized against the tumor. Tumors treated with TLR4 agonist–absorbed GVAX showed increased infiltrating CD4 and CD8 T cells as well as increased numbers of CD86+ cells in the tumor tissue. Draining lymph nodes from the treated mice had enhanced number of activated CD86+, MHCII+, and CD80+ DCs in comparison with GVAX alone and mock-treated groups. ELISPOT assay and in vivo CTL assay showed increased numbers of CTLs specific for the AH1 tumor antigen in mice treated with LPS-absorbed GVAX. Conclusion: TLR4 on antigen-presenting cells in the tumor microenvironment may be targeted by using cell-based vectors for improved antitumor response in vivo. Clin Cancer Res; 17(12); 3984–92. ©2011 AACR.

Expression profile and in vitro blockade of programmed death‐1 in human papillomavirus–negative head and neck squamous cell carcinoma

Treatment with a blocking programmed death‐1 (αPD‐1) antibody recently showed clinical efficacy for various tumor types. In this study, we characterized the expression profile of PD‐1/programmed death‐ligand‐1 (PD‐L1) and the potential of PD‐1 blockade in human papillomavirus (HPV)‐negative head and neck squamous cell carcinoma (HNSCC).

Decomposition of the difference between two rates with hierarchical factors.

A decomposition method for the difference between two rates when data are classified by two factors, one of which may be considered as a more direct factor than the other for the event under consideration, is presented in this paper. The two factors are treated as hierarchical and thus this method is conceptually different from the decomposition methods of Kitagawa (1955) and Das Gupta (1978), in which two factors are treated as symmetrical. Our method is shown to be a balanced version of the Cho-Retherford (1973) decomposition method. Analyses of neonatal mortality rates using our method are presented as an example.

Relapsed or Refractory Double-Expressor and Double-Hit Lymphomas Have Inferior Progression-Free Survival After Autologous Stem-Cell Transplantation

Purpose Double-hit lymphomas (DHLs) and double-expressor lymphomas (DELs) are subtypes of diffuse large B-cell lymphoma (DLBCL) associated with poor outcomes after standard chemoimmunotherapy. Data are limited regarding outcomes of patients with relapsed or refractory (rel/ref) DEL or DHL who undergo autologous stem-cell transplantation (ASCT). We retrospectively studied the prognostic impact of DEL and DHL status on ASCT outcomes in patients with rel/ref DLBCL. Methods Patients with chemotherapy-sensitive rel/ref DLBCL who underwent ASCT at two institutions and in whom archival tumor material was available were enrolled. Immunohistochemistry for MYC, BCL2, and BCL6 and fluorescence in situ hybridization (FISH) for MYC were performed. In cases with MYC rearrangement or copy gain, FISH for BCL2 and BCL6 was also performed. Results A total of 117 patients were included; 44% had DEL and 10% had DHL. DEL and DHL were associated with inferior progression-free survival (PFS), and DHL was associated with poorer overall survival (OS). The 4-year PFS in patients with DEL compared with those with non-DEL was 48% versus 59% ( P = .049), and the 4-year OS was 56% versus 67% ( P = .10); 4-year PFS in patients with DHL compared with those with non-DHL was 28% versus 57% ( P = .013), and 4-year OS was 25% versus 61% ( P = .002). The few patients with concurrent DEL and DHL had a poor outcome (4-year PFS, 0%). In multivariable models, DEL and DHL were independently associated with inferior PFS, whereas DHL and partial response ( v complete response) at transplant were associated with inferior OS. Conclusion DEL and DHL are both associated with inferior outcomes after ASCT in patients with rel/ref DLBCL. Although ASCT remains a potentially curative approach, these patients, particularly those with DHL, are a high-risk subset who should be targeted for investigational strategies other than standard ASCT.

Teen childbearing and educational attainment : A comparison of methods

This research examines the impact of teenage childbearing on secondary school completion, while focusing on the problem of causal ambiguity in the relationships among self-determined behaviours. Techniques for dealing with the teenage childbearing problem are discussed, and results from these methods are compared. Data from the High School and Beyond Study on young women (n = 5257) who were enrolled as sophomores in sample schools in February 1980 and who had not given birth before November 1980 are used. Results indicate that teen childbearing reduces the probability of completing high school by 8% to 10%. Some evidence suggests that programs that target reduction of teen childbearing in improving young womens education and subsequent economic and labor force outcomes.

Movement toward stability as a fundamental principle of population dynamics.

Although convergence to stability is typically a complex and irregular process, the Kullback distance provides a measure that moves consistently to 0 as a population becomes stable. The roots of the Kullback distance are in information theory. but it is a meaningful demographic quantity. It reflects a population’s log momentum, or the amount of growth built into a population’s nonstable age distribution. The rate at which the Kullback distance moves toward 0 is neither constant nor monotonic. At any point in time, however, it decreases by the covariance between a population’s age-specific growth rates and its log momentum. Although the present findings are couched in terms of movement toward stability, they are generally applicable because they relate to the behavior of any population at any instant. It is a fundamental principle of population dynamics that a population is always moving toward the stable population implied by its prevailing fertility and mortality rates, and that the extent of its movement is determined by the covariance between its age-specific growth and its log momentum.

Population momentum expresses population aging.

Population momentum and population aging occur when an initially growing population experiences a reduction in fertility to replacement level. Conceptually and empirically, momentum and aging express the same change, albeit on different scales. Fundamentally, they are two manifestations of the underlying process of demographic transformation. We consider three measures of aging over the transition to stationarity: the increase in mean population age, the decrease in the proportion under age 30, and the increase in the proportion over age 65. The three measures of aging are highly correlated, though the relationship to momentum is weakest for the increase in the proportion over age 65. We find that momentum is linearly related to aging. In both model and actual populations, a one-year increase in mean age translates into about 4.5% more population growth. The population below age 30 does not grow over the transition to stationarity, and the ratio of initial to ultimate proportions under age 30 is virtually identical to momentum.