bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling the Determinants of Semi-Subsistent and Commercial Land Uses in an Agricultural Frontier of Southern Mexico: A Switching Regression Approach
Authors: Vance Colin , Geoghegan Jacqueline
Published: June 2004

The authors analyze the consequences of imperfect output markets for the land-use decisions of semi-subsistence farmers in an agricultural frontier of southern Mexico. The approach is motivated by previous applications of the agriculture household model establishing that the farm household’s productionand consumptiondecisions are analytically nonseparable when markets are not used. Econometric results generated by a switching regression model suggest the importanceof distinguishing the discrete choiceof market participation from thatof area cultivated.
Transferable Development Rights and Forest Protection: An Exploratory Analysis
Authors: Chomitz Kenneth M.
Published: June 2004

As agricultural frontiers expand, and habitats contract, potential conflicts between conservation and development goals increase. Transferable development rights (TDR) programs offer a means of minimizingthe opportunitycosts (in foregoneagricultural rents) of protectinga desired quantity of habitat. These programs may be particularly applicable to Brazil, where long-standing regulations require a fixed proportion of each property to be set aside as a forest reserve. The article develops a simple, geographically explicit simulation model to examine the economic and environmental impact of a hypothetical TDR program under alternative implementation scenarios. Dataonlandcover and land productivity from the Brazilianstate of Minas Gerais are used to calibrate the model. The model shows substantial reductions in conservation cost from widening the geographical scope of trading. Restricting the program to large landholders drastically reduces transactions costs while only mildly reducing the amount of forest placed under protection.
The Daily Consequences of Widowhood
Authors: Utz Rebecca L. , Reidy Erin B. , Carr Deborah , Nesse Randolph , Wortman Camille
Published: June 2004

This study examines (a) whether widowhood affects the performance of daily household activities, (b) the extent to which dependence on children mediates the effect of widowhood on subsequent housework performance, and (c) the extent to which these patterns vary by gender. Using the Changing Lives of Older Couples study, a prospective survey of married persons age 65 and older, we find that late-life widowhood is associated with an increase in men’s housework, yet does not produce a change in women’s subsequent housework performance. Dependency on children mediates the effect of widowhood on housework, suggesting that adult children assist their grieving parents with errands and other household chores. Findingsimplythat the daily consequencesof late-life widowhoodare dependenton the individual, dyadic, and intergenerational characteristics of the older adult.
Interactive Effects of Gender Ideology and Age at First Marriage on Women’s Marital Disruption
Authors: Davis Shannon N. , Greenstein Theodore N.
Published: June 2004

A sample of ever-married women from the NLSY79 is analyzed to examine the effects of age at first marriage and gender ideology on the likelihood of experiencing marital disruption. The authors hypothesize that age at first marriage will have no effect on the likelihood of experiencing marital disruption for non-traditional women, but that there will be a strong negative effect for traditional women. The authors use the log-rate model for piecewise-constant rates to estimate the log odds of respondents’ hazard for experiencing a marital disruption separately for each of the three gender ideologygroups.Findingssuggest that ageat first marriage affects women’s likelihood of marital disruption contingent upon gender ideology. It is suggested that gender ideology is a lens through which women view the world and make decisions and that within each ideology category the factors that affect likelihood of divorce may differ as a result.
Public Perceptions About Father Involvement
Authors: Andrews Arlene Bowers , Luckey Irene , Bolden Errol , Whiting-Fickling Judith , Lind Katherine A.
Published: June 2004

This study of social norms regarding expectations of fathers describes public perceptions based on a statewide, random household telephone survey of 1,010 adults. The results indicate strong public support for communityexpectations about father’s time with child as communicated through workplace provision of paternal leave and flextime, although a majority of respondents had no such benefits. A majority of the respondents agreed that most fathers fulfill responsibilities in the areas of caregiving, financial support, protection, cooperation with the child’s mother, and moral or faith-based guidance. A large minority disagreed, particularly those who were in households with children where the father was not present and those who were divorced or separated. Responses varied by race, gender, and whether the respondent was actively parenting a child. The study affirms the complexity and diversity of social norms about fatherhood and the need to focus on subpopulations.
Family Dynamics, Supportive Relationships, and Educational Resilience During Adolescence
Authors: Crosnoe Robert , Elder Glen H.
Published: June 2004

If problematic relationships with parents are an academic risk factor during adolescence, then nonparental sources of support (e.g., friends, siblings, and teachers) may be arenas of comfort that promote educational resilience in the face of such risk. In a series of structural models using the National Longitudinal Study of Adolescent Health, the authors found that nonparental relationships are more likely to be directly associated with academic behavior than to interact with parent-related risk. Protective interactions occur only among certain subgroups. For example, close relationships with teachers and involvement with friends protect against parent-related academic risk among Asian American adolescents, whereas support from friends operates similarly for younger girls. In other subgroups, parental and nonparental relationships interact but not in a protective way. These patterns demonstrate the complex interplay of developmental ecology and larger social structures during the adolescent stage of life as well as the context-specific nature of resilience.
Better Child Support Enforcement
Authors: Plotnick Robert D. , Garfinkel Irwin , McLanahan Sara S. , Ku Inhoe
Published: June 2004

Stricter child support enforcement may reduce unwed childbearing by raising the costs of fatherhood. The authors investigate this hypothesis using a sample of young women from the National Longitudinal Survey of Youth, to which they add information on state child support enforcement. Models of the probability of a teenage premarital birth and of teenage premarital pregnancy and pregnancy resolution provide tentative evidence that during the early 1980s, teens living in states with higher rates of paternity establishment were less likely to become unwed mothers. This relationship is stronger for non-Hispanic Whites than for non-Hispanic Blacks. The findings suggest that policies that shift more costs of premarital child-bearing to men may reduce this behavior, at least among non-Hispanic Whites.
Crack Mothers in the News: A Narrative of Paternalistic Racism
Authors: Meyers Marian
Published: June 2004

This study examines the story the news tells about “crack mothers” through a narrative analysis of a newspaper series, exploring the major themes and character types from a perspective informed by critical cultural studies and feminist theory. It argues that news studies cannot adequately explore race within representation without also addressing gender and class. The focus of the series analyzed here was the battle to save the children of crack mothers. This narrative of redemption, viewed through the lens of gender, race, and class, is one of a white, professional middle-class working to rescue women and children of the black underclass. The underlying paternalistic racism reflects the intersectionality of gender, race, and class while reinforcing negative stereotypes about African American women.
Business, Advertising, and the Social Control of News
Authors: Craig Robert L.
Published: June 2004

This study demonstrates how businesses employ their advertising to socially control and thus censor viewpoints they do not like. In 1970-71, when the University of Iowa student newspaper the Daily Iowan (DI) started advocating anti–Vietnam War, feminist, and antigovernment positions, businesses withdrew a substantial amount of advertising, which caused the newspaper to lose money. This led to internal pressure within the paper to change content and staff. The newspaper’s board refused to let these pressures affect the newspaper’s staff. The study analyzes the paper’s content, board minutes, and financial data as well as interviews former DI staff and Iowa City businessmen.
There is no South Korea in South Korean Cultural Studies: Beyond the Colonial Condition of Knowledge Production
Authors: Kang Myungkoo
Published: June 2004

This study examines the colonial condition of cultural studies in South Korea that has brought this new stream of thought to both the social sciences and the humanities. This review of South Korean cultural studies provides not only a critique but also reflects on why cultural studies are needed in the twenty-first century. Furthermore, this study will focus on the ways in which South Korean cultural studies has adopted, appropriated, and utilized Western theories of cultural studies since the late 1980s.
Public Sphere and History: Historians’ Response to Habermas on the “Worth” of the Past
Authors: Pinter Andrej
Published: June 2004

This article deals with contested links between the public sphere and history. In particular, it presents a challenge faced by cultural, social, and political historians to use history in clarifying the Habermasian notion of the public sphere. According to the early theory of Jürgen Habermas, history is a necessary ingredient of theoretical conceptualization of the public sphere. Recent research into the history of the public sphere questioned some interpretations of facts on which Habermas based his early theory, but emerging historians’perspectives on the nexus between history and theory of the public sphere uncovered other problems. The role of history in building theories of the public sphere is one such issue. In his later work, Habermas evaded this problem. This article also addresses a third aspect of the problem, which is developed within the history of communication. From this perspective, the history of the public sphere appears much more diverse, dynamic, and ambiguous. According to this position, history appears instrumental in preserving the plurality of possibilities and alternative intellectual routes.
Blessing or Curse?
Authors: Glass Jennifer
Published: June 2004

Little empirical study has been devoted to the impact of employer-sponsored work-family policies on women’s wages. These policies include flexible scheduling, telecommuting, reduced hours of work, and child care assistance. Although these work innovations may make family caregiving easier, many women fear that lower wage growth and blocked mobility will result from the use of these policies. This project followed a midwestern cohort of employed women for 7 years after childbirth, using detailed information about coverage and use of family responsive policies across all jobs held during that period. Results show consistent negative effects of policy use on wage growth after controlling for many productivity-related characteristics, though the effects vary in size depending on the specific policy used, workers’ job mobility, and the respondent’s managerial or professional status.
Self-Composed
Authors: Brown Robert M.
Published: June 2004

The personal statement written for graduate school admission has been a genre virtually ignored by rhetoricians but one that deserves attention. Not only a document of pragmatic importance for applicants, the personal statement is an indicator of disciplinary socialization. The discipline studied here is clinical psychology. Combining quantitative and qualitative methods, the author analyzed a corpus of statements to identify features distinguishing statements of admitted applicants from those of rejected applicants. The findings showed that successful applicants attended more to projecting their future research endeavors and demonstrating their commitments to scientific epistemology. Thus, the author argues that the modifier personal needs qualification, because successful applicants tend to emphasize their public identities as apprentice scientists.
“The Song Is Unfinished”
Authors: Fisher Maisha T.
Published: June 2004

In this article, the author builds on McHenry and Heath’s study of the “literate” and the “literary” and McHenry’s research on “forgotten readers” by examining the often undocumented literacy traditions and practices of men and women of African descent. First, the author traces the legacy of blended traditions of both written and spoken words in African American writing and activism. Continuing with an examination of Black literary and social movements, the author asserts that the recent renaissance of activities around literacy, such as spoken word poetry events as well as writing collectives, contributes to a historical continuum. Ultimately, the author shows the importance of the inextricable link between history, literacy studies, and the teaching of language arts.
Learning to Write History
Authors: Coffin Caroline
Published: June 2004

Historians generally agree that causality is central to historical writing. The fact that many school history students have difficulty handling and expressing causal relations is therefore of concern. That is, whereas historians tend to favor impersonal, abstract structures as providing suitable explanations for historical events and states of affairs, students often focus on human “wants and desires.” The author argues that linguistic analysis can offer powerful insights into how successful students use grammar and vocabulary to build different types of causal explanations as they move through secondary schooling. In particular, the author shows how functionally oriented linguistic analysis makes it possible to discriminate between “narrative” and “analytical” explanations, to distinguish between “enabling” and “determining” types of causality, and to reveal the value of assessing degrees of causal impact.
Toward a Multidimensional Model for Sexual Recidivism Risk
Authors: Doren Dennis M.
Published: June 2004

The paradigm underlying current sexual offender recidivism risk assessment procedures conceptualizes such risk in a linear fashion, ranging on a single continuum from 0% to 100%. Each risk and protective characteristic thought of relevance in an evaluation is used as an indicator of increased or decreased risk, respectively, along that same continuum. This conceptualization of risk was useful as a starting place for the application of empirically supported risk and protective factors. On the other hand, this perspective is likely simplistic and therefore potentially results in some errors that a more sophisticated assessment model would avoid. Recent research findings indicate support for a multidimensional model for sexual recidivism risk. This article explores what we already know about the existence of multiple risk dimensions, what those dimensions may be, and which risk factors assess which dimension. Implications for risk assessment procedures are discussed including how risk evaluations using this model might be conducted.
Cross-Cultural Variability of the Semantic Domain of Emotion Terms: An Examination of English Shame and Embarrass with Japanese Hazukashii
Authors: Rusch Craig D.
Published: June 2004

This research builds on recent work exploring the cross-cultural meaning of emotion terms. The specific hypothesis tested is that within the semantic structure of emotion terms in English and Japanese, the English term embarrass is closer to the Japanese term hazukashii than the English word shame. Similarity ratings of 15 emotion terms are compared between an American English sample (n = 33, including the term shame), another American English sample (n = 33, including the term embarrass instead of shame), and a Japanese sample (n = 32, including the term hazukashii). Correspondence analysis, t test, and quadratic assignment are used to represent the similarity among terms and assess the difference between shame, embarrass, and hazukashii. The hypothesis is supported, and in addition, the overall structure of emotion terms appears stable when one emotion term is replaced with another semantically similar label.
Disruption, Silence, and Creation: The Search for Dialogic Civility in the Age of Anxiety
Authors: Poulos Christopher N.
Published: June 2004

This article searches the contours of anxiety, asking whether anxiety can serve as a springboard to creative engagement in dialogue. Specifically, the article explores the university classroom as a possible site where anxiety might be transformed into the spark of creation. Three opportune moments are examined—disruption, silence, and creation—for the possibilities they present for creating new spaces of energy and new engagement with the call of alterity that erupts in human encounter. The encounter with an “Other” who calls to us from across a chasm of difference—a call that demands a response—is the opening to the possibility of creative engagement that can lead to new levels of transcendence in the classroom and beyond.
Verbal Exchange
Authors: Durham Aisha
Published: June 2004

This is a reflexive piece about the production and reception of personal experience and experimental writing in academia. The author uses poetics as a way to explore the marketability and marginalization of voices (and texts) from the periphery.
The Construction of Correctional Officers: Layers of Emotionality Behind Bars
Authors: Tracy Sarah J.
Published: June 2004

This “layered account,” based on qualitative research gathered at a county jail and state women’s prison, illustrates the ways in which organizational discourses and micropractices encourage emotional constructions such as withdrawal, paranoia, detachment, and an “us-them” mentality among correctional officers. Using philosophies from Michele Foucault, the analysis extends theoretical notions of emotion labor, illustrates the harnessed yet pervasive nature of sexuality in a total institution, and sheds light on the emotional challenges faced by a troubled, hidden, and stigmatized employee group. The text jumps among theoretical arguments, notes about methodology and writing, and creative nonfiction vignettes and in doing so, attempts to embody the emotional and jarring nature of the correctional environment.
Managing A Bulge: Policy Options for Social Security
Authors: Lewis Kenneth A. , Seidman Laurence S.
Published: June 2004

The authors analyze several reasonable policy options for pay-as-you-go Social Security that might be adopted in response to a temporary demographic bulge. The bulge generation enters the economy, works, retires, andexits the economy. Three of the policies maintain a balanced budget. Under the fourth policy, Social Security managers take advantage of the working bulge by initially keeping the replacement rate and tax rate fixed and accumulatinga fund. Then the replacement rate and tax rate are adjusted so that the fund accumulates while the bulge works and then is drawn down to zero as the bulge goes through retirement. This fund accumulation policy would not be adopted by a legislature responding to self-interested adults. Nevertheless, the fund accumulation policy should appeal to a benevolent social planner or citizen because it is the only policy that avoids imposing a nontrivial loss on any cohort in any stage of its life.
Do Government Expenditures Crowd Out Corporate Contributions?
Authors: Day Kathleen M. , Devlin Rose Anne
Published: June 2004

The question of whether corporate charitable contributions are crowded out by government expenditures has been virtually neglected in the literature. While governments are engaged in fiscal realignments, it seems timely to ascertain whether the corporate sector will fund any shortfall in services brought about by government spending adjustments. The authors address this issue using a unique microdata set containing 641 observations on corporate giving over the three-year period from 1990 through 1992. Rather than filling the gap left by government spending reductions, their results suggest that corporate contributions could, in fact, contract—that is, government spending and corporate contributions may be complements rather than substitutes.
Horizontal Equity and Progression When Equivalence Scales Are Not Constant
Authors: Ebert Udo , Lambert Peter J.
Published: June 2004

Household needs must be taken into account when designing an equitable income tax. In this article, the authors are concerned with the use of equivalence scales to achieve horizontal equity. Equivalence scales may be relative or absolute, constant or income-varying. If the equivalence scale is independent of income, horizontal equity is achieved by a form of income splitting (the relative case) or the use of exemptions (the absolute case). However, once one allows the equivalence scale to vary with income, the distinction between relative and absolute scales all but disappears (because one can adjust one form to imitate the other), but a new complication arises because scale values may differ at before and after tax income levels. The authors explore various possible criteria for horizontal equity in this scenario and their implications for vertical equity. In particular, the authors articulate an “equal progression among equals” criterion and showittobe achievable along with horizontal equity under specified conditions.
Inequality and Optimal Redistributive Tax and Transfer Policies
Authors: Zee Howell H.
Published: June 2004

This article argues that the validity of the increasingly fashionable policy advice—maximizing neutrality in taxation and addressing the distributive objective primarily through expenditure policy—is questionablebecause it ignores the revenue-raising aspect of progressive taxation. On the basis of a simple model in which the tax revenue is used exclusively to finance (perfectly) targeted transfers to the poor, the article shows that not only would it be optimal to finance the targeted transfers with progressive taxation, but the optimal progressivity increases unambiguously with growing income inequality. This conclusion holds up under different assumptions about the efficiency cost of taxation and society’s aversion to inequality.
Durable Emissions and Optimal Pigouvian Taxes
Authors: Goel Rajeev K. , Hsieh Edward W. T.
Published: June 2004

This article examines the effectiveness of socially optimal taxes in controlling pollution (or other external effects) generated by a monopolist when pollution is a by-product of production and when emissions themselves are durable. Existing research has paid inadequate attention to the durability aspect, both of the product and of the resulting pollutants. In the two-period model presented here, a social planner minimizes social damage by setting the per-unit Pigouvian tax on a polluting monopolist. Results show that for a given level of production, the durability of emissions and the socially optimal Pigouvian tax are negatively related. This result holds irrespective of the durability of the good under production. The effect of a change in product durability is shown to depend on the output scale effects. Public policy implications are discussed.
Philosophy, Role of Adult Educators, and Learning
Authors: Wang Victor C. X. , Sarbo Linda
Published: June 2004

This article argues that adult educators need to adapt their philosophy and roles to fa-cilitate adult learners’ transformative learning and proposes a model that illustrates this process. The most common purposes of adult education reflect six underlying philosophies as fully discussed by Elias and Merriam. Adult learners possess different needs, interests, and experiences. As teachers modify their roles and methods in re-sponse to their students’ diverse individual characteristics, they must also adapt their underlying philosophical perspective. The authors maintain that in this context, the role of adult educators as facilitators of transformational learning must be redefined and their prevalent humanistic and progressive philosophies must be reexamined.
Notes From a Cuban Diary
Authors: Elvy JC
Published: June 2004

Many consider the 1961 Cuban Literacy Campaign—Campaña de Alfabetización— to be the backdrop for the social, economic, cultural, and ethical transformations that occurred in that country following 1959. The Campaña marked a definitive moment of liberation for women in Cuba, as more than half of the volunteers were women who left their family homes to live and work with the illiterate in the Cuban countryside. This work in progress features photographic portraits of women who participated as literacy teachers together with a cross-section of reflective testimonies to provide tex-tural components for a broader reading of this massive event.
Beyond Reflective Competency
Authors: Generett Gretchen Givens , Hicks Mark A.
Published: June 2004

This article explores the challenges of creating an antioppressive, transformative cur-riculum for hope among practicing teachers. As the authors investigate the impact of their curriculum, they discovered that although the skills of reflection, collaboration, and continuous inquiry led teachers to new insight—even change in teacher prac-tice—it failed to inspire teachers to take an antioppressive stance in remedying op-pressive practices in schools. Building on the body of literature related to the African American struggle against oppression, the authors argue that for a curriculum to be transformative, it must encourage a symbiotic relationship between hope and action. The authors conclude that audacious hope-in-action is an essential part of teaching transformatively.
Late for School
Authors: Cohen Judith Beth
Published: June 2004

Graduates of Lesley University’s Learning Community Bachelor’s program were interviewed 2 to 5 years following the completion of their degrees. The sample included 3 men and 12 women, with 1 African American, 1 Cuban American, and 3 Saudi national participating. Data gathered from student papers and participant observations together with the students’ narratives highlighted the following themes: the effect of an interrupted life narrative, a disorienting residency experience, the importance of peer support, the power of individually designed studies and writing, the impact on family and personal relationships, a growing concern for social change, increased global understanding, openness to art and creativity, and an interest in lifelong learning. This study’s focus on the residential experiences of adult learners adds participant voices to the knowledge base of transformative learning.
Experiencing Transformative Education in the “Corridors” of a Nontraditional Doctoral Program
Authors: Gilly M. Sue
Published: June 2004

This article describes an experience of transformative education that was not an official part of a degree program. The author and two other doctoral students formed a peer group that worked together for more than 2 years because of their common interests in the experience of successful groups. All three group members produced dissertations that studied different aspects of that peer-group experience. The author’s dissertation study concluded that the term living learning group best captured their group experience. That study also found two intertwined themes, collaboration and relationship, as central aspects of their group experience.
Quadrinity Online
Authors: Feller Amanda , Jensen Allison , Marie Diane , Peddigrew Brenda , Clinchard-Sepeda Lori , Campbell Elizabeth
Published: June 2004

The overarching principle of this article is to provide pedagogy of transformative learning, specifically where online learning is concerned. By offering quadrinity learning—a fuller expression of transformative learning—the authors offer a framework to educators, facilitators, social actors, and others committed to transformation. The intention is to validate, highlight, and name the pattern that is often the undercurrent of various facilitators working within the contexts such as teaching, facilitation, and grassroots activism. In essence, this pattern is one of the whole self. Effective learning and transformative practice requires sharing one’s whole self and acknowledging the wholeness of others.
α+-thalassemia protects African children from severe malaria
Authors: Mockenhaupt Frank P. , Ehrhardt Stephan , Gellert Sabine , Otchwemah Rowland N. , Dietz Ekkehart , Anemana Sylvester D. , Bienzle Ulrich
Published: June 2004

The high frequency of α+-thalassemia in malaria-endemic regions may reflect natural selection due to protection from potentially fatal severe malaria. In Africa, bearing 90% of global malaria morbidity and mortality, this has not yet been observed. We tested this hypothesis in an unmatched case-control study among 301 Ghanaian children with severe malaria and 2107 controls (62% parasitemic). In control children, α+-thalassemia affected neither prevalence nor density of Plasmodium falciparum. However, heterozygous α+-thalassemia was observed in 32.6% of controls but in only 26.2% of cases (odds ratio [OR], 0.74; 95% confidence interval [CI], 0.56-0.98). Protection against severe malaria was found to be pronounced comparing severe malaria patients with parasitemic controls (adjusted OR in children < 5 years of age, 0.52; 95% CI, 0.34-0.78) and to wane with age. No protective effect was discernible for homozygous children. Our findings provide evidence for natural selection of α+-thalassemia in Africa due to protection from severe malaria.
Gastric Cancer Surgery: Morbidity and Mortality Results From a Prospective Randomized Controlled Trial Comparing D2 and Extended Para-Aortic Lymphadenectomy—Japan Clinical Oncology Group Study 9501
Authors: Sano Takeshi , Sasako Mitsuru , Yamamoto Seiichiro , Nashimoto Atsushi , Kurita Akira , Hiratsuka Masahiro , Tsujinaka Toshimasa , Kinoshita Taira , Arai Kuniyoshi , Yamamura Yoshitaka , Okajima Kunio
Published: June 2004

Purpose

Radical gastrectomy with regional lymphadenectomy is the only curative treatment option for gastric cancer. The extent of lymphadenectomy, however, is controversial. The two European randomized trials only reported an increase in operative morbidity and mortality, but failed to show survival benefit, in the D2 lymphadenectomy group. We conducted a randomized controlled trial to compare the Japanese standard D2 and D2 + para-aortic nodal dissection.

Patients and Methods

Only experienced surgeons in both procedures from 24 Japanese institutions participated in the study. Patients with potentially curable gastric adenocarcinoma (T2-subserosa, T3, or T4) who were surgically fit were intraoperatively randomized. Postoperative morbidity and hospital mortality were recorded prospectively in a fixed format and were compared between the two groups in this study.

Results

A total of 523 patients were randomized between July 1995 and April 2001. Postoperative complications were reported in 24.5% of all patients. Although the morbidity for the extended surgery group (28.1%) was slightly higher than the standard group (20.9%), there was no difference in the incidence of four major complications (anastomotic leak, pancreatic fistula, abdominal abscess, pneumonia) between the two groups. Hospital mortality was reported at 0.80%: one patient in each group died of operative complications, while one from each group died of rapid progressive cancer while inpatient.

Conclusion

Specialized surgeons could safely perform gastrectomy with D2 lymphadenectomy in patients with low operative risks. Para-aortic lymphadenectomy could be added without increasing major surgical complications in this setting.
Surgical Factors Influence Bladder Cancer Outcomes: A Cooperative Group Report
Authors: Herr Harry W. , Faulkner James R. , Grossman H. Barton , Natale Ronald B. , deVere White Ralph , Sarosdy Michael F. , Crawford E. David
Published: June 2004

Purpose

A randomized, cooperative group trial (Southwest Oncology Group 8710, Intergroup 0080) reported that neoadjuvant chemotherapy improved the survival of patients with locally advanced bladder cancer who were treated with radical cystectomy. We evaluated whether surgical factors from patients enrolled onto the study predicted bladder cancer outcomes.

Patients and Methods

Surgical and tumor factors were recorded from surgical and pathologic reports from 268 patients with muscle-invasive bladder cancer who received radical cystectomy. Cystectomies were performed by 106 surgeons in 109 institutions. Half of the patients received neoadjuvant methotrexate, vinblastine, doxorubicin, and cisplatin (MVAC) chemotherapy. Variables were tested in univariate and multivariate analyses for associations with postcystectomy survival (PCS) and local recurrence (LR) in all patients receiving cystectomy.

Results

Five-year PCS and LR rates were 54% and 15%, respectively. A multivariate model adjusted for MVAC (P = .97), age (P = .03), pathologic stage (P = .0002), and node status (P = .04) showed that surgical variables associated with longer PCS were negative margins (v positive; hazard ratio [HR], 0.37; P = .0007), and ≥ 10 nodes removed (v < 10; HR, 0.51; P = .0001). These associations did not differ by treatment arms (P > .21 for all tests of interactions between treatment and surgical variables). Predictors of LR in a multivariate model adjusted for MVAC (P = .16), pathologic stage (P = .02), and node status (P = .37) were positive margins (v negative; odds ratio [OR], 11.2; P = .0001) and fewer than 10 nodes removed (v ≥ 10; OR, 5.1; P = .002).

Conclusion

Surgical factors influence bladder cancer outcomes after cystectomy, after adjustment for pathologic factors and neoadjuvant chemotherapy usage.
Cell-autonomous and cell non-autonomous signaling through endothelin receptor B during melanocyte development
Authors: Hou Ling , Pavan William J. , Shin Myung K. , Arnheiter Heinz
Published: June 2004

The endothelin receptor B gene (Ednrb) encodes a G-protein-coupled receptor that is expressed in a variety of cell types and is specifically required for the development of neural crest-derived melanocytes and enteric ganglia. In humans, mutations in this gene are associated with Waardenburg-Shah syndrome, a disorder characterized by pigmentation defects,deafness and megacolon. To address the question of whether melanocyte development depends entirely on a cell-autonomous action of Ednrb, we performed a series of tissue recombination experiments in vitro, using neural crest cell cultures from mouse embryos carrying a novel Ednrb-null allele characterized by the insertion of a lacZ marker gene. The results show that Ednrb is not required for the generation of early neural crest-derived melanoblasts but is required for the expression of the differentiation marker tyrosinase. Tyrosinase expression can be rescued,however, by the addition of Ednrb wild-type neural tubes. These Ednrb wild-type neural tubes need not be capable of generating melanocytes themselves, but must be capable of providing KIT ligand, the cognate ligand for the tyrosine kinase receptor KIT. In fact, soluble KIT ligand is sufficient to induce tyrosinase expression in Ednrb-deficient cultures. Nevertheless, these tyrosinase-expressing, Ednrb-deficient cells do not develop to terminally differentiated,pigmented melanocytes. Pigmentation can be induced, however, by treatment with tetradecanoyl phorbol acetate, which mimics EDNRB signaling, but not by treatment with endothelin 1, which stimulates the paralogous receptor EDNRA. The results suggest that Ednrb plays a significant role during melanocyte differentiation and effects melanocyte development by both cell non-autonomous and cell-autonomous signaling mechanisms.
Muscle-specific RING finger-2 (MURF-2) is important for microtubule, intermediate filament and sarcomeric M-line maintenance in striated muscle development
Authors: McElhinny Abigail S. , Perry Cynthia N. , Witt Christian C. , Labeit Siegfried , Gregorio Carol C.
Published: June 2004

The efficient functioning of striated muscle is dependent upon the structure of several cytoskeletal networks including myofibrils, microtubules, and intermediate filaments. However, little is known about how these networks function together during muscle differentiation and maintenance. In vitro studies suggest that members of the muscle-specific RING finger protein family (MURF-1, 2, and 3) act as cytoskeletal adaptors and signaling molecules by associating with myofibril components (including the giant protein, titin), microtubules and/or nuclear factors. We investigated the role of MURF-2, the least-characterized family member, in primary cultures of embryonic chick skeletal and cardiac myocytes. MURF-2 is detected as two species (∼55 kDa and ∼60 kDa) in embryonic muscle, which are down-regulated in adult muscle. Although predominantly located diffusely in the cytoplasm, MURF-2 also colocalizes with a sub-group of microtubules and the M-line region of titin. Reducing MURF-2 levels in cardiac myocytes using antisense oligonucleotides perturbed the structure of stable microtubule populations, the intermediate filament proteins desmin and vimentin, and the sarcomeric M-line region. In contrast, other sarcomeric regions and dynamic microtubules remained unaffected. MURF-2 knock-down studies in skeletal myoblasts also delayed myoblast fusion and myofibrillogenesis. Furthermore, contractile activity was also affected. We speculate that some of the roles of MURF-2 are modulated via titin-based mechanisms.
Molecular interactions of Polo-like-kinase 1 with the mitotic kinesin-like protein CHO1/MKLP-1
Authors: Liu Xiaoqi , Zhou Tianhua , Kuriyama Ryoko , Erikson Raymond L.
Published: June 2004

Polo-like kinases and kinesin-like motor proteins are among the many proteins implicated in the execution of cytokinesis. Polo-like-kinase 1 (Plk1) interacts with the mitotic kinesin-like motor protein CHO1/MKLP-1 during anaphase and telophase, and CHO1/MKLP-1 is a Plk1 substrate in vitro. Here, we explore the molecular interactions of these two key contributors to mitosis and cytokinesis. Using the transient transfection approach, we show that the C-terminus of Plk1 binds CHO1/MKLP-1 in a Polo-box-dependent manner and that the stalk domain of CHO1/MKLP-1 is responsible for its binding to Plk1. The stalk domain was found to localize with Plk1 to the mid-body, and Plk1 appears to be mislocalized in CHO1/MKLP-1-depleted cells during late mitosis. We showed that Ser904 and Ser905 are two major Plk1 phosphorylation sites. Using the vector-based RNA interference approach, we showed that depletion of CHO1/MKLP-1 causes the formation of multinucleate cells with more centrosomes, probably because of a defect in the early phase of cytokinesis. Overexpression of a non-Plk1-phosphorylatable CHO1 mutant caused cytokinesis defects, presumably because of dominant negative effect of the construct. Finally, CHO1-depletion-induced multinucleation could be partially rescued by co-transfection of a non-degradable hamster wild-type CHO1 construct, but not an unphosphorylatable mutant. These data provide more detailed information about the interaction between Plk1 and CHO1/MKLP-1, and the significance of this is discussed.
Redox state regulates HIF-1α and its DNA binding and phosphorylation in salmonid cells
Authors: Nikinmaa Mikko , Pursiheimo Saijaliisa , Soitamo Arto J.
Published: June 2004

Rainbow trout (Oncorhynchus mykiss) hypoxia-inducible factor-1 (HIF-1) is a heterodimeric transcription factor structurally similar to mammalian HIF-1. It consists of HIF-1α and HIF-1β subunits, of which the HIF-1α subunit confers the hypoxia sensitivity. HIF-1α is rapidly degraded by a proteasome under normal oxygen (21% O2) conditions, mainly as a result of prolyl hydroxylation needed for protein destabilization. Although prolyl hydroxylation at conserved proline residues is a major factor controlling HIF-1α stability, the redox state of the cells may, in addition, influence the function of HIF-1α like proteins by influencing their stability, DNA binding and phosphorylation. Sensitivity of the protein to oxidation/reduction may be due to cysteine residues at critical positions. The predicted amino acid sequence of rainbow trout HIF-1α contains several unique cysteine residues, notably in the DNA-binding area at position 28 and in the transactivation domain of the molecule in the vicinity of the conserved proline residue at position 564 of mammalian HIF-1α. In the present studies we have investigated if the redox state influences HIF-1α stability, DNA binding and phosphorylation in two established salmonid cell lines RTG-2 and CHSE-214. The results indicate that reducing conditions, achieved using N-propylgallate (nPG) or N-acetylcysteine (NAC), stabilize HIF-1α, facilitate its DNA binding, and increase its phosphorylation even under normal oxygen conditions. On the other hand, oxidizing conditions, achieved using L-buthionine sulfoximine (BSO) dampen the hypoxia response. Furthermore, the hypoxia-like effect of cobalt is increased in the presence of the reducing agent. On the basis of these results, we suggest that redox state influences the accessibility of the conserved prolyl residues to oxygen-dependent hydroxylation and the accessibility of the residues involved in the phosphorylation of HIF-1α.
Common husbandry-related variables in biomedical research with animals
Authors: Reinhardt Viktor
Published: June 2004

Common, often overlooked, variables in biomedical research with animals are reviewed. The barren primary enclosure is an abnormal living environment for laboratory animals. Species-appropriate enrichment attenuates some of the distress resulting from chronic understimulation. Social deprivation distress of individually-caged social animals is best mitigated by the provision of compatible companionship. Biotelemetry and positive reinforcement training avoid or minimize stress reactions that typically occur when animals are forcibly restrained during procedures. The variables, 'light' and 'position of living quarters' are inherent in the multi-tier caging system. To date there is no satisfactory alternative other than the single-tier cage arrangement that eliminates both variables. Removing test animals from their familiar home environment and from their cage mates for procedures introduces stress as an avoidable influential variable. Music may become an important variable if not all subjects are exposed to it. Disturbance time cannot be controlled as an extraneous variable but it should at least be mentioned to explain possible incongruities of data. A positive relationship between animal care personnel and research subjects is a key requisite to minimize stress as a data-confounding variable.
Rats socially-reared and full fed learned an autoshaping task, showing less levels of fear-like behaviour than fasted or singly-reared rats
Authors: Molina-Hernández Miguel , Téllez-Alcántara N. Patricia
Published: June 2004

During the learning of instrumental tasks, rats are usually fasted to increase reinforced learning. However, fasting produces several undesirable side effects. The aim of this study was to test the hypothesis that control rats, i.e. full-fed and group-reared rats, will learn an autoshaping task to the same level as fasted or singly-reared rats. The interaction between fasting and single-rearing of rats was also tested. Results showed that control rats and fasted rats acquired the autoshaping task similarly, independently of rearing condition or gender. However, fasted or singly-reared rats produced fear-like behaviour, since male rats group-reared and fasted (85% body/wt, P <0.05), male rats singly-reared (full fed, P <0.05; 12 h fasted, P <0.05; 85% body/wt, P <0.05), female rats group-reared (12 h fasted, P <0.05; 85% body/wt, P <0.05) and female rats singly reared (full fed, P <0.05; 12 h fasted, P <0.05; 85% body/wt, P <0.05) displayed reduced amounts of time exploring the open arms of the elevated plus-maze. In conclusion, control rats learned the autoshaping task to the same level as fasted or singly-reared rats. However, fasting or single-rearing produced fear-like behaviour. Thus, the training of control rats in autoshaping tasks may be an option that improves animal welfare.
The laboratory rabbit: an animal model of atherosclerosis research
Authors: Yanni Amalia E.
Published: June 2004

The aim of the present mini review is to describe the laboratory rabbit, an animal that has been widely used for the study of atherosclerosis, the leading cause of mortality in Western society. Due to the fact that the rabbit exhibits hypercholesterolaemia within a few days of an administration of a high cholesterol diet, it is very sensitive to the inducement of atheromatic lesions. The administration of different types of diets can cause different types of lesions. Although these lesions do not develop as tissue plaques, a great number of researchers use this animal model to test the effectiveness of drugs because of their similarity to human fatty streaks. The generation over recent years of transgenic rabbits with alterations in specific genes is expected to help with the elucidation of the mechanisms underlying the initial and developmental stages of the disease. The laboratory rabbit is significantly broadening our understanding on the pathogenesis of atherosclerosis.
Protocol to refine intestinal motility test in mice
Authors: Nunes Marona Hérida Regina , Bastos Lucchesi Maria Beatriz
Published: June 2004

We propose a new protocol intended to conform to the 3Rs (replacement, reduction, and refinement) principle, using animals fasted for 3 h to control intestinal motility, which reduced stress in the animals. In this new protocol, mice are deprived of food for a short time (3 h) and are not killed. The mice are observed until evacuation containing charcoal is observed, and the experimental results are based on the charcoal evacuation time. The present study may aid the formulation of recommendations that can be included in revised guidelines relating to the fasting time of mice. This new concept of an intestinal motility test conforms with respectful science.
Influence of O3/O2–pneumoperitoneum as an oxidative stressor on duration of anaesthesia, loss of different reflexes and cytokine mRNA expression
Authors: Schulz S. , Bette M. , Schlimme S. , Mutters R. , Hoffmann S. , Menendez S.
Published: June 2004

We analysed the effect of intraperitoneal insufflated ozonized oxygen on the anaesthetic strength generated by tribromoethanol, ketamine/xylazine, chloral hydrate, pentobarbital, and urethane in male Wistar rats. High dosages of anaesthetic drugs normally used for deep surgical anaesthesia were injected. The ozonized oxygen gas mixture was given five times daily on five consecutive days at 0.8 mg ozone/kg body weight before anaesthesia. The reflexes were measured 15, 30, 60, 90, 120, 180, and 240 min after injection of the anaesthetic drug. The sleeping time and the loss and regain of six different reflexes on noxious and non-aversive stimuli were recorded during the 4 h of observation. O3/O2–pneumoperitoneum (O3/O2–PP) reduced the sleeping time induced by tribromoethanol and ketamine/xylazine and increased it for chloral hydrate and pentobarbital. In accordance to the changes in the duration of anaesthesia, the O3/O2–PP induced significant changes in the loss of different reflexes. Additionally, the modulatory effect of the anaesthetic drugs on splenic cytokine mRNA expression was further influenced by O3/O2–PP. Thus, the influence of an oxidative stressor on anaesthetic potency and on the resting immune system has to be taken into account for experimental designs in which surgical anaesthesia is necessary for small laboratory animals.