bluuebunny/crossref_metadata_2025 huggingface dataset:
Emic-Etic Conflicts as Explanation of Nonparticipation in Adult Education among the Maya of Western Guatemala
Authors: Cutz German , Chandler Paul
Published: July 2003

A 1996-1997 field study of reasons for nonparticipation in literacy programs among illiterate Mayan adults in rural western Guatemala demonstrated an emic-etic distinction within adult education. This distinction may be the critical determinant of success or failure of adult education efforts and can also explain gaps between theory, research, and the practice of adult education. Literacy programs have aimed to convert illiterate adults into literates. However, emic concepts held by illiterate adults in this study have made these attempts fail and deterred illiterate adults from participation in literacy programs. These concepts are generated and supported at four structural levels: individual-4a) literacy is not work and (b) the concept of schooling; family-(a) family obligations and moral values and (b) humiliation of the adult male; community-(a) the concept of Maya and (b) moral economy; national-4a) loss of cultural identity, (b) indigenous community, and (c) irrelevance of literacy.
A Group Learning Intervention into How Women Learn Empathy in Prison
Authors: Kilgore Deborah W.
Published: July 2003

A group learning intervention was carried out with a group of women incarcerated in a Texas state penitentiary. The author found that empathic practices typically learned and employed by female inmates in prison are limited to those containing a strong cognitive component. On the other hand, the logic of practice that developed within the research-driven learning group was one involving empathic practices with a strong affective component. The repertoire of possible empathic practices available to participants was thus expanded to include these alternatives. It is speculated that a program such as the one developed by the research team would better prepare participants for the variety of social relationships in which they engage in the “free world.”
Ethical Issues and Codes of Ethics: Views of Adult Education Practitioners in Canada and the United States
Authors: Gordon Wanda , Sork Thomas J.
Published: July 2003

Although the ethics of practice has become increasingly visible in the adult education literature over the past two decades, little empirical research has been done to inform the dialogue and debate. The purpose of this study was to examine the views of adult education practitioners in British Columbia about the need for a code of ethics and about the ethical issues, concerns, and dilemmas experienced in their practice. The study was an approximate replication of research carried out in Indiana reported by McDonald and Wood. This study was undertaken to broaden the empirical database within adult education, provide further insight into the ethics of practice, and determine similarities and differences between Canadian and American adult educators in their encounters with ethical issues and their views about codes of ethics. Major findings confirm positive practitioner views about codes of ethics and are generally consistent with the findings reported by McDonald and Wood.
Contextual and Individual Factors and the Use of Influencing Tactics in Adult Education Program Planning
Authors: Hendricks Susan M.
Published: July 2003

Building on the work of Cervero and Wilson and Yang, this multivariate study examined the relationships between contextual factors (power and conflict in the adult education planning relationship), individual factors (perceived problem-solving effectiveness and years of experience as an educational planner), and different influencing tactics used in adult education program planning. Participants were students and faculty members from multiple adult education graduate programs in North America. Results indicated that in conflicted planning situations, counteracting was favored as an influencing tactic over reasoning and consulting. In consensual planning situations, reasoning and consulting were favored, and counteracting was deemed ineffective. Program planners may benefit from a greater understanding of the power and influencing tactics used in different situations. Further work can better identify and measure the factors that are most critical when negotiating power and interests. Future research should focus on enhancing instrument reliability and validity, clarifying the theoretical model, and using a broader sample of program planners.
Lifelong Learning: A Postmodern Condition of Education?
Authors: Edwards Richard , Usher Robin
Published: July 2003

In recent years, there has been much discussion of the significance of postmodernism and postmodernity for the study and practice of adult education. At the same time, lifelong learning has emerged as a significant strand of policy around the globe, reconfiguring the institutions and purposes of education. This article examines the complication of lifelong learning with some of the changes associated with the postmodern condition, in particular, the growth of performativity alongside a certain "unruliness" of knowledge. The article also suggests that lifelong learning signifies that the loss of mastery is associated with postmodern notions of ambivalence and incredulity. The article argues that given their interrelationship, lifelong learning can be constructed as a postmodern condition of education.
Misogyny, Women, and Obstacles to Tertiary Education: A Vile Situation
Authors: Stalker Joyce
Published: July 2003

For decades, researchers, theoreticians, and practitioners have attempted unsuccessfully to ensure women's full and active participation in all areas of tertiary education. This article uses empirical data to demonstrate that misogyny (a hatred of women) creates a useful, sharper theorization from which to explicate obstacles to women's participation in tertiary education. Using misogyny to interpret traditional deterrence themes such as lack of energy, family commitments, and child care responsibilities produces new meanings for these barriers. Such theorization encompasses many of the complex experiences of women and explains what we intuitively understand about their implications. This article suggests that a theorization based in misogyny has the ability to explain obstacles to women's participation in tertiary education, to offer new solutions, and to challenge us to move away from "nice " concepts that have failed to deliver safe and productive pathways for women who wish to participate in tertiary education.
Black Women in Nursing Education Completion Programs: Issues Affecting Participation
Authors: Aiken Lolita Chappel , Cervero Ronald M. , Johnson-Bailey Juanita
Published: July 2003

The purpose of this study was to explain factors that encouraged and discouraged the participation of Black women in RN completion programs. A qualitative design and a Black feminist theoretical framework guided the study. Ten Black women were interviewed: 7 attended RN completion programs, and 3 were recent graduates. Factors that encouraged the participation of Black women can be grouped into two areas: intrapersonal and cultural factors. Factors that discouraged participation of the Black women in the study can be grouped into two areas: the experience of being the "other" and the culture of racism. The study concludes that Black women in RN completion programs are constantly aware of themselves as the "other" in the classroom as well as in practice and that individual and institutional racism is a barrier in RN completion programs.
Adult Education Quarterly from 1989 to 1999: A Content Analysis of all Submissions
Authors: Taylor Edward W.
Published: July 2003

The intent of this study was to conduct an analysis of all submissions (accepted and rejected) to Adult Education Quarterly from 1989 to 1999. Previous reviews of the journal had only analyzed published articles. Including all submissions revealed a more complete analysis of trends, and patterns of acceptances were revealed. Trends for the previous decade included continued dominance of academic, male, single-author submissions from North America. However; there have been increasing numbers of submissions by women, of a qualitative research design, and on topics about gender/diversity and training/continuing professional education. Also, acceptance rates were higher than average for men; academics; submissions from Australia/New Zealand, and Europe; qualitative research; and the subjects of adult development, gender/diversity, evaluation/testing, philosophy, and research methods. As a result, a more complete picture of the publication activity of the journal is possible when all the submissions, not just acceptances, are included in a content analysis.
Repositioning Ideology Critique in a Critical Theory of Adult Learning
Authors: Brookfield Stephen
Published: July 2003

Contemporary adult educational readings of the Frankfurt School of critical theory, as interpreted via Habermas, risk sliding into an exclusive engagement with the pragmatic dimensions of his thought to the exclusion of its Marxist underpinnings and its concern with ideology critique. Building on Max Horkheimer's recently republished essay on "Traditional and Critical Theory," this article attempts to reposition ideology critique as a learning process crucial to the realization of adulthood. It discusses critical theory as a response to Marx and argues that a critical theory of adult learning should focus on how adults learn to recognize and challenge ideological domination and manipulation. Such learning is necessary if adults are to counteract the continuous reproduction of blatantly unequal structures and create more inclusive democratic arrangements. The article concludes with a warning for critical theory to be on guard against its own ossification and entombment by engaging with the pragmatist spirit.
Should I Stay or Should I Go? Investigating Cambodian Women’S Participation and Investment in Adult ESL Programs
Authors: Skilton-Sylvester Ellen
Published: July 2003

Drawing on the work of Norton Peirce, the author argues that traditional views of adult motivation and participation are limited because they do not address the complex relationships among adult learners’ identities, the social contexts of their daily lives, the classroom context, and investment in learning English. By focusing on the lived experiences of four Cambodian women, this research suggests the value of investigating the variety and commonality of adult experience within a single ethnolinguistic group. The findings go beyond social identity to address issues of cultural identity relevant to understanding participation in adult English-as-a-Second-Language (ESL) programs. This analysis shows how shifting identities of these women at home and as current or future workers, and the ways these identities are connected to the work of the classroom, have much to do with their investment in participating in particular adult ESL programs.
Toward a Workplace Pedagogy: Guidance, Participation, and Engagement
Authors: Billett Stephen
Published: July 2003

This article proposes bases for a workplace pedagogy. Planes of intentional guidance and sequenced access to workplace activities represent some key workplace pedagogic practices. Guidance by others, situations, and artifacts are central to learning through work because the knowledge to be learned is historically, culturally, and situationally constituted. However, the quality of learning through these planes of activities and guidance is ultimately premised on the workplace’s participatory practices, which shape and distribute the activities and support the workplace affordance workers and fromwhich they learn. Situational and political processes underpin these workplace affordances. Yet participatory practices are reciprocally constructed because individuals elect how to engage in and learn from what workplaces afford them. A workplace pedagogy is founded in these coparticipatory practices and needs to account for how workplaces invite access to activities and guidance and how individuals elect to participate in what the workplace affords.
Living and Learning with HIV/AIDS: Transformational Tales Continued
Authors: Baumgartner Lisa M.
Published: July 2003

The purpose of this qualitative study was to examine the nature of learning during the incorporation of HIV/AIDS into identity over time. It sought to understand participants’continued meaningmaking of their chronic illness. Interviews conducted with the same 11 participants in 1995, 1998, and 1999 composed the data set. Data were analyzed using psychological, biographical, and linguistic approaches to narrative analysis. Fourmajor findings emerged: First, the nature of learning was transformational, and the perspective transformation remained stable. Second, meaning scheme changes evident in 1998 were acted on. Third, new meaning schemes included (a) an increased appreciation for the human condition and (b) an expanded view of intimacy. Fourth, social interaction was integral to the learning process. The stability of the perspective transformation, the additional changes in meaning schemes, and the importance of social interaction in the learning process have implications for adult education.
Reassessing Subjectivity, Criticality, and Inclusivity: Marcuse’s Challenge to Adult Education
Authors: Brookfield Stephen
Published: July 2003

For his influence on Habermas alone, Marcuse’s work deserves attention by adult educators. If Habermas is a central theoretical reference point for our field, then knowledge of a precursor’s ideas that Habermas found so provocative can bring us to a fuller understanding of Habermas’s own work. But this is not the chief reason for reading Marcuse. In his own right, Marcuse articulates an analysis of subjectivity, criticality, and inclusivity that has powerful implications for adult education. Although Marcuse did not write as an adult educator or make explicit reference to the field, his concerns frequently intersect with those of adult educators concerned with how adults learn their own liberation.
Socioeconomic Contributions of Adult Learning to Community: A Social Capital Perspective
Authors: Balatti Jo , Falk Ian
Published: July 2003

As an explanatory concept that relates skills and knowledge to economic outcomes, “human capital” has dominated for decades. Skills and knowledge are certainly central attributes of a learning society. Given the limitations of economy as a proxy for social well-being, however, two outstanding questions about the impact of adult learning on community linger: What are the multiple impacts of adult learning on community? How do these occur? To address these questions adequately, the theoretical construct of social capital is proving useful. This article examines the impacts of such a nebulous entity as adult learning on diverse socioeconomic domains, and it looks at how these impacts occur. Outcomes of learning are discussed against the eight Organization for Economic Cooperation and Development indicators of social well-being. Social capital—its networks, trust, and shared values—emerges as the missing link in explaining the integrated role of knowledge and identity resources in generating adult learning benefits.
Overcoming Alienation as the Practice of Adult Education: The Contribution of Erich Fromm to a Critical Theory of Adult Learning and Education
Authors: Brookfield Stephen
Published: July 2003

Erich Fromm's analysis of the commodification of contemporary life, his description of automation conformity, and his call for the overcoming of alienation represent important, though ignored. elements of the critical tradition that have great resonance for the practice of adult education. Drawing particularly on the early Marx of the Economic and Philosophical Manuscripts. Fromm conducted a radical, yet highly accessible, analysis of adult life and learning. He argued that learning to penetrate ideological obfuscation, and thereby overcome the alienation this obfuscation induced, was the learning task of adulthood. Adult education as a force for resistance would make people aware of ideological manipulation and educate them for participatory democracy. By calling his ideas humanist, Fromm ensured that his work beckoned enticingly to many educators. But his normative humanism was a militant, Marxist humanism, entailing the abolition of capitalist alienation and the creation of democratic socialism.
Is there Madness in the Method? Representations of Research in Lifelong Learning
Authors: Edwards Richard , Clarke Julia , Harrison Roger , Reeve Fiona
Published: July 2003

In the move from viewing research as purely technical, objective, and rational to understanding it as a social practice embedded in particular cultural, political, and historical contexts, we raise the question of how reality is represented in research practices and products. Thus, the purpose of this article is to examine the "performativity" of text in constructing and reporting research. To do that, this article explores the process of formulating research questions for an empirical study of conceptions of flexibility and lifelong learning in the context of further education in the United Kingdom. We examine the implications of an analytical reflexivity for the representation of research projects. This analysis of representation is (re)presented in three parallel versions of our research: an algorithmic tale, a tale of improvisations, and a reflexive tale.
Support Systems, Psychological Functioning, and Academic Performance of Nontraditional Female Students
Authors: Carney-Crompton Shawn , Tan Josephine
Published: July 2003

Traditional (18-22 years of age) and nontraditional (35-44 years of age)female students were compared on various aspects of their social support systems, child care, psychological functioning (depression and anxiety), and academic performance. Traditional students exhibited poorer psychological functioning when they were less satisfied with their emotional support network. In contrast, psychological functioning within the nontraditional students was independent of the amount and satisfaction with their emotional and instrumental social support resources. Despite having fewer sources of support, nontraditional students reported better academic performance than did the traditional students.
Andragogy’s Detectives: A Critique of the Present and a Proposal for the Future
Authors: Rachal John R.
Published: July 2003

The empirical literature examining the efficacy of andragogy remains, after over three decades, both inconclusive and beset by considerable variability in definition, resulting in differing approaches to andragogy’s implementation. This empirical record, residing largely in unread dissertations, is critiqued with a view toward establishing criteria for an operational, researchable, consensus-based definition of Knowles’ famous formulation. Seven such criteria are offered. Whether these—or other—criteria reach a kind of critical mass of agreement for future investigators is open for further discussion. But the current muddle of definitions and implementations has effectually stalled research. Unless that discussion reaches some approximate consensus, adult education’s most familiar and most debated theory will remain a fragmented article of faith at best, a fond illusion at worst.
Humanism and Individualism: Maslow and his Critics
Authors: Pearson Elaine M. , Podeschi Ronald L.
Published: July 2003

This analysis explores the philosophical issue of the individual-society relationship through a focus on Abraham Maslow's humanistic psychology and its significant influence on adult education in the United States. Analyzing the points of contention between the key assumptions of Maslow and recent critics, particularly Marxist and postmodernist scholars, the study concludes with perspectives that do not abandon humanistic possibilities while pinpointing its problems.
Enhanced Longevity in Tau Mutant Syrian Hamsters, Mesocricetus auratus
Authors: Oklejewicz Malgorzata , Daan Serge
Published: July 2003

The single-gene mutation tau in the Syrian hamster shortens the circadian period by about 20% in the homozygous mutant and simultaneously increases the mass-specific metabolic rate by about 20%. Both effects might be expected to lead to a change in longevity. To test such expectations, the life span of male and female hamsters from three genotypes (wild-type, heterozygous, and homozygous tau mutants, all derived from heterozygote crosses to randomize the genetic background) was recorded in constant darkness. Male hamsters lived significantly longer than females: the overall average life span was 96.9 weeks (SE = 2.5, n = 118) for males and 82.0 weeks (SE = 2.1, n = 99) for females. To our surprise, male and female homozygous mutant hamsters lived significantly longer rather than shorter compared to wild-types. For males, the difference between the two genotypes was on average 14%; for females, the difference was 16%. The mortality rate of wild-type males was significantly different from that of homozygous tau males but not different from that of heterozygotes. Overall, survival of wild-type females was statistically distinguishable from both heterozygous and homozygous mutant females. Male and female wild-type hamsters were heavier than homozygote mutants throughout the entire life span, and heterozygous mutants had intermediate weights. There was no correlation between body mass and life span, and the causes of the extended life span in tau mutant hamsters remain unresolved.
The Intergeniculate Leaflet, but Not the Visual Midbrain, Mediates Hamster Circadian Rhythm Response to Constant Light
Authors: Morin L. P. , Pace L.
Published: July 2003

Several studies have demonstrated a variety of effects of intergeniculate leaflet (IGL) lesions on circadian rhythm regulation. Recent studies have suggested the possibility that certain rhythm functions attributed to the IGLare actually controlled by retinorecipient midbrain nuclei or other brain areas connected to the IGL. The present investigations evaluated whether midbrain lesions previously shown to block the phasic actions of benzodiazepine would also reduce or eliminate the period-lengthening effect of constant light (LL), a function that has been attributed to the IGL. Experiment 1 established that the circadian period of controls lengthened by about 0.57 h when the animals were transferred from constant dark (DD) to LL, but the magnitude of change was attenuated by about 50% in animals with IGL lesions caused by the neurotoxin N-methyl-D-aspartate (NMDA). In experiment 2, controls were compared to groups receiving either NMDAlesions of the pretectum or tectum or knife cuts designed to sever connections between the IGL and more medial retinorecipient nuclei. As in experiment 1, there were no differences between groups with respect to circadian period in DD. However, unlike experiment 1, all groups lengthened period equally in LL (overall mean increase = 0.57 h). Thus, the effect of LL on circadian period appears to be a joint result of photic information arriving at the circadian clock directly from the retinohypothalamic tract and indirectly through the IGLvia the geniculohypothalamic tract, without involvement of visual midbrain. The results may have implications for the anatomical basis of Aschoff's rule.
Circadian Clock Resetting by Sleep Deprivation without Exercise in Syrian Hamsters: Dark Pulses Revisited
Authors: Mistlberger Ralph E. , Belcourt Jodi , Antle Michael C.
Published: July 2003

Circadian rhythms in Syrian hamsters can be phase shifted by procedures that stimulate wheel running (“exercise”) in the mid-subjective day (the hamster's usual sleep period). The authors recently demonstrated that keeping hamsters awake by gentle handling, without continuous running, is sufficient to mimic this effect. Here, the authors assessed whether wakefulness, independent of wheel running, also mediates phase shifts to dark pulses during the midsubjective day in hamsters free-running in constant light (LL). With running wheels locked during a 3 h dark pulse on day 3 of LL, hamsters ( N = 16) averaged only 43 ± 15 min of spontaneous wake time and phase shifted only 24 ± 43 min. When wheels were open during a dark pulse, two hamsters remained awake, ran continuously, and showed phase advance shifts of 7.3 h and 8.7 h, respectively, whereas the other hamsters were awake <60 min and shifted only 45 ± 38 min. No animals stayed awake for 3 h without running. Additional time in LL (10 and 20 days) did not potentiate the waking or phase shift response to dark pulses. When all hamsters were sleep deprived with wheels locked during a dark pulse, phase advance shifts averaged 261 ± 110 min and ranged up to 7.3 h. These shifts are large compared to those previously observed in response to the 3 h sleep deprivation procedure. Additional tests revealed that this potentiated shift response is dependent on LL prior to sleep deprivation but not LL after sleep deprivation. A final sleep deprivation test showed that a small part of the potentiation may be due to suppression of spontaneous wheel running by LL. These results indicate that some correlate of waking, other than continuous running, mediates the phase-shifting effect of dark pulses in the mid-subjective day. The mechanism by which LLpotentiates shifting remains to be determined. The lack of effect of subsequent LL on the magnitude of shifts to sleep deprivation in the dark suggests that LL reduces responsivity to light by processes that take >3 h of dark to reverse.
Phase Shifting the Hamster Circadian Clock by 15-Minute Dark Pulses
Authors: Rosenwasser Alan M. , Dwyer Suzanne M.
Published: July 2003

The mammalian circadian pacemaker can be phase shifted by exposure to a period of darkness interrupting otherwise continuous light. Circadian phase shifting by dark pulses was interpreted originally as reflecting a photic mirrorimage mechanism, but more recent observations suggest that dark pulseinduced phase shifting may be mediated by a nonphotic, behavioral state-dependent mechanism. The authors recently presented evidence indicating that the dark-pulse phase response curve (PRC) is in fact a complex function, reflecting both photic mirror image and nonphotic mechanisms at different phases of the circadian cycle. Previous studies of dark pulse-induced phase shifting have universally employed relatively long (2 to 6 h) pulses, which complicates PRC analysis due to the extended segment of the underlying PRC spanned by such a long pulse. The present study was therefore designed to examine the phaseshifting effects of brief 15-min dark pulses presented at both mid-subjective day and subjective dusk, and to explore the possible activity dependence of these effects by using physical restraint to prevent evoked locomotor activity. The results indicate that 15-min dark pulses are effective phase-shifting stimuli at both midday and dusk. Furthermore, as with longer dark pulses, phase shifting by 15-min dark pulses is completely blocked by physical restraint during subjective day but combines in a simple additive manner with the independent phaseshifting effect of restraint at subjective dusk.
Induced Travel Demand: Research Design, Empirical Evidence, and Normative Policies
Authors: Cervero Robert
Published: July 2003

Claims of induced travel demand have seemingly paralyzed the ability to rationalize road development in the United States. Methodological issues related to resolution of analysis, measurement, specification, and normative significance are raised in this article. Five types of empirical studies— facility specific, model forecasts, area studies using proxy elasticities, area studies using partial elasticities, and disaggregate analyses—are reviewed and critiqued. Efforts to simultaneously model road supply and demand relationships and identify interaction effects are also reviewed. Based on a meta-analysis, the preponderance of research points to an appreciable induced demand effect; however, problems related to research design continue to cast doubts about our understanding of this phenomenon.
Does Sustainable Development Offer a New Direction for Planning? Challenges for the Twenty-First Century
Authors: Berke Philip R.
Published: July 2003

The practice and scholarship of planning has shifted from physical design to process. Process emphasizes diversity, openness, and consensus but is not fully equipped to offer a shared vision in political arenas dominated by fragmentation and conflict. Newurbanism has revived the idea that planning is about physical design, but this concept does not fully embrace a holistic vision of community building. This article explains howsustainable development extends the positive attributes of the first two approaches and offers a multigenerational vision of community building. This vision integrates multiple societal values and enhances local imagination, understanding, and commitment to defining solutions for the common good.
Synthesis and Antimutagenic Properties of Novel Systems Based on Poly(Quaternized Ammonium) Salts
Authors: Alexandrova V. A. , Obukhova G. V. , Topchiev D. A.
Published: July 2003

The adsorptive capacity on the model bilayer lipid membrane and antimutagenic activity of synthetic polycations of diallyldimethylammonium chloride (DADMACh) were studied. A correlation between the total positive charge of a macro-ion and the polymer efficiency as a bioprotector was found. A number of ternary copolymers (TCP) containing different amounts of di(tertbutyl)phenol (TBPh) in the side chain of a DADMACh and acrylic acid binary copolymer (30:70 mol%) were prepared. A correlation between the amount of the TBPh in the TCP(TBPh) structure and both the antiradical and the antimutagenic efficiencies was obtained. Taking into account the correlations found in model synthetic polycations, modification of chitosan was fulfilled. Chitosan derivatives containing quaternary ammonium groups and TBPh in the polymer side chain improved the antimutagenic efficiency of the polymer in a plant test-system from 48 to 93%.
N-(2-Hydroxypropyl)methacrylamide Copolymer-9-Aminocamptothecin Conjugate: Colon-Specific Drug Delivery in Rats
Authors: Sakuma Shinji , Lu Zheng-Rong , Pecharová Barbara , Kopečková Pavla , Kopeček Jindřich
Published: July 2003

An N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer conjugate containing 9-aminocamptothecin (9-AC) boundvia a spacer containing an aromatic azo bond and leucylalanine (P-Azo-Leu-Ala-9-AC) was synthesized. The in vivo pharmacokinetic profile after oral administration was examined in rats and comparedto free 9-AC. The aromatic azo bond of P-Azo-Leu-Ala-9-AC was stable in stomach and small intestine; the delivery of a large amount of intact conjugate to the colon was achieved. In the colon, the azoreductase activity first cleaved the azo bond followed by peptidase catalyzed cleavage of the leucylalanyl drug derivative resulting in the release of free 9-AC. However, the release rate from the conjugate was not fast enough to achieve high colon concentrations of free 9-AC. The results of the study suggest design features for the second generation of conjugates, including the use of a side-chain with a higher cleavage rate in the colon, combined with the incorporation of bioadhesion technology, to increase colon transit time.
Pneumocystis Carinii Pneumonia in Adult Non-HIV Disorders
Authors: Gilmartin Geoffrey S. , Koziel Henry
Published: July 2003

Pneumocystis carinii pneumonia (PCP) remains a serious infection in the immunocompromised host (in the absence of HIV infection) and presents significant management and diagnostic challenges to ICU physicians. Non-HIV PCP is generally abrupt in onset, and follows a fulminate course with high rates of hospitalization, ICT admission, respiratory failure, and requirement for intubation. Mortality is generally high, especially if mechanical ventilation is required. Non-invasive ventilatory support may be considered, although the rapid progression to respiratory failure often necessitates intubation at the time of presentation. Bronchoscopy is often required to establish the diagnosis, and empirical antimicrobial treatment specifically targeted to P. carinii should be initiated while awaiting confirmation. Adjunctive corticosteroids may accelerate recovery, although their use has not yet been established in non-HIV PCP. For the ICU physicians to diagnose PCP, the non-specific presentation of an acute febrile illness and respiratory distress with diffuse pulmonary infiltrates requires a high clinical index of suspician, familiarity with clinical conditions associated with increased risk for PCP, and a low threshold for bronchoscopy to establish the diagnosis.
Prolonged Mechanical Ventilation after Cardiac Surgery in Young Children: Incidence, Etiology, and Risk Factors
Authors: Davis Steve , Cox Amy C. , Piedmonte Marion , Drummond-Webb Jonathan J. , Mee Roger B. B. , Harrison A. Marc
Published: July 2003

Children undergoing congenital heart surgery require postoperative mechanical ventilation. Despite recent advances, prolonged mechanical ventilation (PMV) is necessary in some patients and may increase the risk of post-operative complications. The purpose of this study was to identify incidence and risk factors for PMV. The authors performed a retrospective chart review. They defined PMV as ventilation longer than 48 hours. Mixed-effects linear regression models were used to assess the relationship between each factor and duration of mechanical ventilation. Separate models were developed for preoperative, intraoperative, and postoperative periods. To determine the extent to which a combination of risk factors would predict PMV, the most significant variables were adopted to fit a model using number of risk factors to predict PMV. Two hundred twelve children ≤ 36 months were included. Eleven (5.2%) children died perioperatively. Of the patients, 72.6% (143/197) were extubated by 48 hours. Age < 6 months, perioperative infection, inotrope use > 48 hours, total parenteral nutrition use, and failed extubation were associated with PMV. PMV occurred in 28% of the patients in this study. The presence of 2 risk factors predicted PMV with a sensitivity of 86% and a specificity of 94%.
Neutrophil-Related Inflammatory Mediators in Septic Acute Respiratory Distress Syndrome
Authors: Kinoshita Manabu , Ono Satoshi , Mochizuki Hidetaka
Published: July 2003

To disclose the participation of neutrophils in septic acute respiratory distress syndrome (ARDS), characteristics of various inflammatory mediators were examined in septic patients. Forty-seven gram-negative septic patients were divided into ARDS (n = 23) and non-ARDS (n = 24) groups at the transferred point to the intensive care unit. The mediators were measured simultaneously at the transferred point, and then subsequently on days 1, 3, and 5. At the transferred point, the ARDS group showed significantly higher levels of interleukin-8 (IL-8), macrophage inflammatory peptide-1-alpha (MIP-1-α), soluble intercellular adhesion molecule-1 (sICAM-1), and neutrophil elas-tase despite lower neutrophil counts compared to the non-ARDS group. The ARDS group sustained significantly higher levels of sICAM-1 until day 5 and neutrophil elas-tase until day 1 compare to the non-ARDS group. Furthermore, nonsurviving ARDS patients (n = 8) showed significantly higher levels of tumor necrosis factor-alpha, IL-6, IL-8, and IL-10 compared to surviving ARDS patients (n = 15) at the transferred point. In conclusion, neutrophil-related inflammatory mediators, IL-8, MIP-1-α, sICAM-1, and neutrophil elastase, appear to possibly participate in septic ARDS. Cytokines might also play an important role in the mortality of such cases.
Effect of Manual Hyperinflation on Hemodynamics, Gas Exchange, and Respiratory Mechanics in Ventilated Patients
Authors: Paratz Jennifer , Lipman Jeffrey , McAuliffe Mary
Published: July 2003

The authors investigated the effect of manual hyperinflation (MHI) with set parameters applied to patients on mechanical ventilation on hemodynamics, respiratory mechanics, and gas exchange. Sixteen critically ill patients post-septic shock, with acute lung injury, were studied. Heart rate, arterial pressure, and mean pulmonary artery pressure were recorded every minute. Pulmonary artery occlusion pressure, cardiac output, arterial blood gases, and dynamic compliance (Cdyn) were recorded pre- and post-MHI. From this, systemic vascular resistance index (SVRI), cardiac index, oxygen delivery, and partial pressure of oxygen: fraction of inspired oxygen (PaO2:FiO2) ratio were calculated. There were significant increases in SVRI ( P < 0.05) post-MHI and diastolic arterial pressure ( P < 0.01) during MHI. Cdyn increased post-MHI ( P < 0.01) and was sustained at 20 minutes post-MHI ( P < 0.01). Subjects with an intrapulmonary cause of lung disease had a significant decrease ( P = 0.02) in PaO2:FiO2, and those with extrapulmonary causes of lung disease had a significant increase ( P < 0.001) in PaO2:FiO2 post-MHI. In critically ill patients, MHI resulted in an improvement in lung mechanics and an improvement in gas exchange in patients with lung disease due to extrapulmonary events and did not result in impairment of the cardiovascular system.
Hyponatremia in Critically Ill Patients
Authors: Vachharajani T. J. , Zaman F. , Abreo K. D.
Published: July 2003

Disorders of sodium and water metabolism are frequently encountered in hospitalized patients. Hyponatremia in critically ill patients can cause significant morbidity and mortality. Inappropriate treatment of hyponatremia can add to the problem. The diagnosis and management of salt and water abnormalities in critically ill patients is often challenging. The increasing knowledge about aquaporins and the role of vasopressin in water metabolism has enhanced our understanding of these disorders. The authors have outlined the general approach to the diagnosis and management of hyponatremia. A systematic approach by clinicians, using a detailed history, physical examination, and relevant diagnostic tests, will assist in efficient management of salt and water problems.
Pneumothorax in Patients With Acute Respiratory Distress Syndrome: Pathophysiology, Detection, and Treatment
Authors: Woodside Kenneth J. , vanSonnenberg Eric , Chon Kenneth S. , Loran David B. , Tocino Irena M. , Zwischenberger Joseph B.
Published: July 2003

Pneumothorax is a frequent and potentially fatal complication of mechanical ventilation in patients with acute respiratory distress syndrome (ARDS). Prompt recognition and treatment of pneumothoraces is necessary to minimize morbidity and mortality. The radiologic and clinical signs of pneumothoraces in ARDS patients may have unusual and subtle features. Furthermore, small pneumothoraces in these patients can cause severe hemodynamic or pulmonary compromise. Sparse clinical literature exists on when or how to treat pneumothoraces once they develop in patients with ARDS. In this article, the authors review the pathogenesis, radiologic signs, clinical significance, and treatment of pneumothoraces in ARDS patients. Treatment options include traditional tube thoracostomy, open thoracotomy, and image-guided percutaneous catheters.
The Role of the α2-Adrenoceptor Agonist Dexmedetomidine in Postsurgical Sedation in the Intensive Care Unit
Authors: Martin Eike , Ramsay Graham , Mantz Jean , Sum-Ping S. T. John
Published: July 2003

Dexmedetomidine was evaluated for sedation of 401 postsurgical patients in this double-blind, randomized, placebocontrolled, multicenter trial. Dexmedetomidine or saline was started on arrival in the intensive care unit (ICU) (1.0 mcg/kg for 10 minutes), then titrated at 0.2 to 0.7 mcg/kg/h to effect. Patients could be given propofol if necessary. Morphine was administered for pain. Sixty percent of the dexmedetomidine patients required no other sedative to maintain an RSS ≥ 3; 21% required < 50 mg propofol. In contrast, 76% of the control group received propofol; 59% required ≥ 50 mg. Dexmedetomidine patients required significantly less morphine for pain relief (P < .001). Continuously given throughout the ICU stay, dexmedetomidine had no effect on respiratory rate, oxygen saturation, duration of weaning, or times to extubation. Nurses judged the dexmedetomidine patients were easier to manage. Later, fewer dexmedetomidine patients remembered pain or discomfort. The majority of dexmedetomidine patients maintained blood pressures within normal range, without rebound. Hypertension, atelectasis, and rigors occurred more frequently in the control group, while hypotension and bradycardia occurred more frequently in the dexmedetomidine group. Preoperative cardiovascular conditions were not risk factors for dexmedetomidine patients.
Accidental Oral Poisoning Caused by Rdx (Cyclonite): A Report of 5 Cases
Authors: KüçükardalI Yaşar , Acar H. Volkan , Özkan Sezai , Nalbant Selim , Yazgan Yusuf , Atasoyu E. Murat , Keskin Özcan , Naz Alişan , Akyatan Nevzat , Gökben Merih , Danaci Mehmet
Published: July 2003

The explosive RDX (hexogen, cyclonite) is usually used for the production of C-4 explosive. The rare occurrence of accidental and intentional RDX intoxications has been reported during manufacturing process or in wartime. In this article, the authors report 5 cases of accidental oral RDX poisoning. On admission, observed signs and symptoms included repetitive generalized tonic-clonic convulsions, postictal coma, lethargy, confusion, hyperreflexia, postictal amnesia, nausea, vomiting, abdominal tenderness, sinusal tachycardia, dysrhythmia with frequent ventricular premature beats, generalized muscle spasms, and myoclonus. Leukocytosis, mild anemia, methemoglobinemia, elevated levels of blood glucose, serum aspartate transaminase, alanine transaminase, lactic dehydrogenase, creatine phosphokinase, amilase, hypokalemia, metabolic acidosis, proteinuria, glucosuria, and myoglobinuria were also noted. Plasma RDX concentrations were 268 to 969 ng/mL at 3 hours of ingestion. For management, supportive and symptomatic measures were taken. Whole-bowel irrigation might have been an effective therapeutic procedure due to probable slow gastrointestinal absorption of RDX. Three patients who developed severe metabolic acidosis underwent urgent hemodialysis. All patients were discharged 7 to 21 days after admission without any sequelae. Plasma RDX levels were strongly correlated with the clinical and laboratory manifestations. The available toxicological data on this rare accidental poisoning are reviewed in light of the literature.
In Vitro Interactions of Biomedical Polyurethanes with Macrophages and Bacterial Cells
Authors: Visai Livia , Rindi Simonetta , Speziale Pietro , Petrini Paola , Farè Silvia , Tanzi M. Cristina
Published: July 2003

Three commercial medical-grade polyurethanes (PUs), a poly-ether-urethane (Pellethane), and two poly-carbonate-urethanes, the one aromatic (Bionate) and the other aliphatic (Chronoflex), were tested for macrophages and bacterial cells adhesion, in the presence or absence of adhesive plasma proteins. All the experiments were carried out on PUs films obtained by solvent casting. The wettability of these films was analysed by measuring static contact angles against water.

The ability of the selected PUs to adsorb human fibronectin (Fn) and fibrinogen (Fbg) was checked by ELISA with biotin-labelled proteins. All PUs were able to adsorb Fn and Fbg(Fn > Fbg). Fn adsorption was in the order: Pellethane > Chronoflex > Bionate, the highest Fbg adsorption being detected onto Bionate (Bionate > Chronoflex > Pellethane).

The human macrophagic line J111, and the two main bacterial strains responsible for infection in humans (Staphylococcus aureus Newman and Staphylococcus epidermidis 14852) were incubated in turn with the three PUs, uncoated or coated with plasma proteins.

No macrophage or bacterial adhesion was observed onto uncoated PUs.

PUs coated with plasma, Fn or Fbgpromoted bacterial adhesion (S. aureus > S. epidermidis), whereas macrophage adhered more onto PUs coated with Fn or plasma. The coating with Fbg did not promote cell adhesion. Pellethane showed the highest macrophage activation (i.e. spreading), followed, in the order, by Bionate and Chronoflex.
Gelatin Microspheres and Sponges for Delivery of Macromolecules
Authors: Ulubayram Kezban , Eroglu Inci , Hasirci Nesrin
Published: July 2003

Gelatin microspheres and gelatin sponges were prepared by coacervation and freeze drying techniques, respectively. Both systems were crosslinked with glutaraldehyde. The mean diameter of the microspheres were in the range of 40–80 mm and the mean pore size of the sponges was 130–220 mm depending on the preparation conditions. Bovine serum albumin (BSA) was added into the preparation solutions and entrapped in the microspheres and sponges. BSA addition to sponges was also achieved by addition of BSA-containing microspheres into the sponges. The release kinetics of BSA from the prepared systems were examined. Studies demonstrated that release is dependent on the amount of BSA present in the system and crosslinking densities of microspheres. It was concluded that gelatin microspheres and gelatin sponges are promising carrier matrices for macromolecules.
Comparison of the Fracture Resistance of Six Denture Base Acrylic Resins
Authors: Uzun Gülay , Hersek Nur
Published: July 2003

Fracture strength of denture base resins is of great concern, and many approaches have been used to strengthen acrylic resin dentures. Fracture resistance of six commercially available acrylic resin denture base materials were compared, through impact and transverse strength tests. Three rapid heat-polymerised resins (QC 20, Meliodent and Trevalon), two high-impact strength resins (Trevalon Hi and Lucitone 199) and a strengthened injection-moulded acrylic resin (SR Ivocap plus) were included in the study. Twenty acrylic resin test specimens were fabricated from each resin. For impact strength test, ten notched specimens were tested in a Charpy-type impact tester. The other ten specimens were used for transverse strength tests, deflection and modulus of elasticity values were also determined, which were assessed with three-point bending tests using an Universal Testing Machine.

Impact test values showed significant differences among acrylic resins ( F = 4.817 p = 0.0). SR Ivocap resin showed the highest impact strength values, followed by Trevalon Hi and Lucitone 199. The transverse strength test values were not significant when six acrylic resins were compared ( F = 1.705 p = 0.151).

High-impact resins can be recommended to increase the impact strength of denture base. If the cause of fracture is mechanical or anatomical, strengthened acrylic resins and conventional acrylic resins have similar fracture resistance.
Enhanced Wear Resistance of Ball-And-Socket Joints of Dental Implants by Means of Titanium Gaseous Nitriding
Authors: Gil F. J. , Canedo R. , Padrós A. , Sada E.
Published: July 2003

The aim of this research is the surface hardening of the ball-and-socket joint of dental implants by means of heat treatments in order to obtain titanium nitrides. These nitrides minimize the wear of the titanium used in prosthesis. In this paper the optimum heat treatment, the hardness and the wear resistance are described in relation to the ball-and-socket joint without heat treatment.