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Attachment from infancy to early adulthood in a high-risk sample: continuity, discontinuity, and their correlates.

This study explores the stability of attachment security and representations from infancy to early adulthood in a sample chosen originally for poverty and high risk for poor developmental outcomes. Participants for this study were 57 young adults who are part of an ongoing prospective study of development and adaptation in a high-risk sample. Attachment was assessed during infancy by using the Ainsworth Strange Situation (Ainsworth & Wittig) and at age 19 by using the Berkeley Adult Attachment Interview (George, Kaplan, & Main). Possible correlates of continuity and discontinuity in attachment were drawn from assessments of the participants and their mothers over the course of the study. Results provided no evidence for significant continuity between infant and adult attachment in this sample, with many participants transitioning to insecurity. The evidence, however, indicated that there might be lawful discontinuity. Analyses of correlates of continuity and discontinuity in attachment classification from infancy to adulthood indicated that the continuous and discontinuous groups were differentiated on the basis of child maltreatment, maternal depression, and family functioning in early adolescence. These results provide evidence that although attachment has been found to be stable over time in other samples, attachment representations are vulnerable to difficult and chaotic life experiences.

Adolescent↗

Earned-secure attachment status in retrospect and prospect.

Past research with the Berkeley Adult Attachment Interview demonstrates that retrospectively defined earned-secures (who coherently describe negative childhood experiences) parent as effectively as do continuous-secures (who coherently describe positive childhood experiences), but manifest liabilities in the form of depressive symptomatology. This article presents data from a 23-year longitudinal study that replicate and extend prior research, testing a key premise that earned-secures so defined actually have a history of insecure attachments that change over time and/or endure consistently harsh or ineffective parenting in their youth. Discrepant with assumptions, retrospective earned-secures were not more likely than continuous-secures to have been anxiously attached in infancy and were observed in childhood and adolescence to have encountered among the most supportive and structured maternal parenting in a high-risk sample. Prospectively defined earned-secures (operationalized using participants' infant attachment classifications) did indeed go on to have success in their close relationships, many without reporting relatively high levels of internalizing distress in adulthood.

Adaptation, Psychological↗

Survival analysis in clinical trials: past developments and future directions.

The field of survival analysis emerged in the 20th century and experienced tremendous growth during the latter half of the century. The developments in this field that have had the most profound impact on clinical trials are the Kaplan-Meier (1958, Journal of the American Statistical Association 53, 457-481) method for estimating the survival function, the log-rank statistic (Mantel, 1966, Cancer Chemotherapy Report 50, 163-170) for comparing two survival distributions, and the Cox (1972, Journal of the Royal Statistical Society, Series B 34, 187-220) proportional hazards model for quantifying the effects of covariates on the survival time. The counting-process martingale theory pioneered by Aalen (1975, Statistical inference for a family of counting processes, Ph.D. dissertation, University of California, Berkeley) provides a unified framework for studying the small- and large-sample properties of survival analysis statistics. Significant progress has been achieved and further developments are expected in many other areas, including the accelerated failure time model, multivariate failure time data, interval-censored data, dependent censoring, dynamic treatment regimes and causal inference, joint modeling of failure time and longitudinal data, and Baysian methods.

Biometry↗

Exploring the use of soft X-ray microscopy for imaging subcellular structures of the inner ear.

The soft X-ray microscope at the Lawrence Berkeley National Laboratory was developed for visualization of biological tissue. Soft X-ray microscopy provides high-resolution visualization of hydrated, non-embedded and non-sectioned cells and is thus potentially an alternative to transmission electron microscopy. Here we show for the first time soft X-ray micrographs of structures isolated from the guinea-pig inner ear. Sensory outer hair cells and supporting pillar cells are readily visualized. In the hair cells, individual stereocilia can easily be identified within the apical hair bundle. The underlying cuticular plate is, however, too densely composed or too thick to be clearly visualized, and thus appears very dark. The cytoplasmic structures protruding from the cuticular plates as well as the fibrillar material surrounding and projecting from the cell nuclei can be seen. In the pillar cells the images reveal individual microtubule bundles. Soft X-ray images of the acellular tectorial membrane and thin two-layered Reissner's membrane display a level of resolution comparable to low-power electron microscopy.

Animals↗

Prevention of alcohol-related accidents in the community.

This paper establishes a conceptual and operational basis for development of community prevention programs to reduce alcohol-related accidents. A public health perspective of accidents is proposed as the philosophical basis for local prevention interventions in which accidents are viewed as system problems (system outputs, if you will) not simply problems caused by a few alcohol-dependent individuals. Since there are no examples of controlled community prevention research projects (trials) which have demonstrated a reduction in community-level alcohol-related accidents, such controlled trials are needed in the future. An example of one being developed by the Prevention Research Center, Berkeley, CA is provided. Without such controlled trials, prevention research will be unable to demonstrate that such accidents can actually be reduced. This paper explores the applications of a public health perspective to the prevention of alcohol-involved accidents at the community level including a conceptual model of alcohol-involved trauma and suggested design, alternative local interventions, possible outcome measures, and phases for community prevention of alcohol-related accidents.

Accident Prevention↗

Controversies in nursing ethics: a historical review.

The author critiques the dialectic between justice-based ethics and an ethic of caring from a historical perspective (by analogy with the dialectic between agape and friendship). Justice-based ethics have been problematic for nursing because of the decontextualized approach. The ethic of caring is problematic because caring, being contextual, is particularistic and therefore can be based on morally irrelevant factors, such as liking. There is a tradition of writing which seeks to reconcile the particularistic obligations of friendship with the moral duty to all others equally. Ideas from the following authors are reviewed for relevance to nursing: Aristotle, Aelred of Rievaulx, Augustine, John Cassian, Cicero, George Berkeley, Immanuel Kant, Michel de Montaigne, Jeremy Taylor and Max Weber. The authors concludes by noting that both sides of the dialectic are synthesized in the lived experience of individuals. A synthesis in thought is called for on this basis.

Acquired Immunodeficiency Syndrome↗

Extended storage of single-donor apheresis platelets in CLX blood bags: effect of storage on platelet morphology, viability and in vitro function.

A CLX (Cutter Laboratories, Berkeley, Calif.) bag system was evaluated for storage of single-donor apheresis platelets collected with the Haemonetics V-50 blood processor. Concentrates (n = 21) containing 3.9-5.2 x 10(11) platelets in 292 (+/- 41.8) ml were stored in two 1-liter bags for 7 days at 22 degrees C. pH was well maintained, declining from an initial pH of 7.0 (+/- 0.04) to 6.92 (+/- 0.20) after 7 days. Platelet morphology, response to a hypotonic stimulus and aggregation induced by paired agonists (epinephrine and ADP, or collagen) were also well-preserved. Concentrates with a wide variation of platelet yields (2.0 greater than or equal to 5.2 x 10(11), n = 43) also maintained pH (6.96 +/- 0.26), morphology and aggregation when stored for 7 days. All platelet concentrates (n = 64) were sterile at collection. Single-donor apheresis platelets may be stored in this bag system for up to 7 days.

Blood Component Removal↗

Combat experience and emotional health: impairment and resilience in later life.

War's influence on emotional health includes potential psychological gains as well as losses. In a sample of 149 veterans from longitudinal samples at the Institute of Human Development, University of California, Berkeley, this study explores two questions on the legacy of combat in World War II and the Korean conflict. The first concerns the subjective experience or meanings of combat that veterans hold in later life, with particular attention to how such accounts are linked to the severity of combat and postwar adaptations. The second question links these accounts to the psychosocial functioning of veterans before the war and in later life using reports from veterans and their spouses and Q-sort ratings in adolescence and at age 40. Findings center on veterans of heavy combat. Compared to the noncombatants and light combat veterans, these men were at greater risk of emotional and behavioral problems in the postwar years. In mid-life, they hold mixed memories of painful losses and life benefits associated with military experience. Clinical ratings show that heavy combat veterans became more resilient and less helpless over time when compared to other men. As in the case of life events generally, short- and long-term effects may impair and enhance personal growth.

Adaptation, Psychological↗

Continuities and consequences of interactional styles across the life course.

Behavior patterns can be sustained across the life course by two kinds of person-environment interaction. Cumulative continuity arises when an individual's interactional style channels him or her into environments that themselves reinforce that style, thereby sustaining the behavior pattern across the life course through the progressive accumulation of its own consequences. Interactional continuity arises when an individual's style evokes reciprocal, sustaining responses from others in ongoing social interaction, thereby reinstating the behavior pattern across the individual's life course whenever the relevant interactive situation is replicated. Using archival data from the Berkeley Guidance Study (Macfarlane, Allen, & Honzik, 1954), we present evidence for the operation of these two continuity-promoting processes by identifying individuals who were ill-tempered, shy, or dependent in late childhood and then tracing the continuities and consequences of these interactional styles across the subsequent 30 years of their lives in the domains of work and family. The importance of the sociocultural context in mediating these continuities and consequences is stressed.

Adaptation, Psychological↗

Perceptions of children's body sizes among mothers living on the Texas-Mexico border (La Frontera).

OBJECTIVES: The objectives of this study were to quantify mothers' perceptions of their children's sizes and explore mothers' views of child growth, diet, activity, and health. Photographs of children from the Berkeley Longitudinal Growth Study (on Centers for Disease Control and Prevention [CDC] Web site) were used to stimulate discussion with mothers about child sizes. DESIGN: A descriptive, cross-sectional study examined mothers' perceptions of their children's size and their beliefs about child size, growth, and health. SAMPLE: The convenience sample included 25 mother-child dyads of 3-year-old children at two Head Start Centers in a county on the Texas-Mexico border. All mothers self-identified as Hispanic. MEASUREMENT: Photographs of children were shown to elicit mothers' perceptions of children's body sizes. The children and mothers were weighed and measured and their body mass indices (BMIs) were computed. The mothers were interviewed about their beliefs on child health, growth, and feeding. RESULTS: No congruence was found between mothers' perceptions of child sizes in the pictures and their children's sizes. CONCLUSIONS: Using CDC photographs does not appear to be a useful way to educate mothers about child body sizes. A child who is happy, active, and can accomplish normal childhood activities is not considered by mothers as overweight, regardless of the child's BMI.

Adult↗

Individual and population penalized regression splines for accelerated longitudinal designs.

In an accelerated longitudinal design (ALD), individuals enter the study at different points of their growth trajectory and are observed over a short time span relative to the entire time span of interest. ALD data are combined across independent units to provide an estimate of an overall population curve and predictions of individual patterns of change. As a modest extension of the work of Ruppert et al. (2003, Semiparametric Regression, Cambridge University Press), we develop a computationally efficient procedure for the application of longitudinal semiparametric methods under ALD sampling schemes. We compare balanced and complete longitudinal designs to ALDs using the Berkeley Growth Study data and apply our method to longitudinal magnetic resonance imaging (MRI) brain structure size (volume) measurements from an ongoing developmental study. Potential applications extend beyond growth studies to many other fields in which cost and feasibility constraints impose restrictions on sample size and on the numbers and timings of repeated measurements across subjects.

Adolescent↗

Suzanne F. Delbanco on the Leapfrog Group and employer purchasing power. Interview by Pamela K. Scarrow.

Suzanne F. Delbanco, PhD MPH, is the first executive director of The Leapfrog Group, founded by the Business Roundtable. The Leapfrog Group's goal is to mobilize employer purchasing power to initiate breakthrough improvements in the safety, quality, and overall value of healthcare for American consumers. The group's growing consortium of more than 155 Fortune 500 companies and other large private and public healthcare purchasers provides health benefits to more than 34 million Americans; these companies spend more than 62 billion dollars on healthcare annually. Dr. Delbanco is a member of the National Committee for Quality Assurance Purchaser Advisory Council and a board member of Bridges to Excellence. Before joining The Leapfrog Group, she was a senior manager at the Pacific Business Group on Health (PBGH), where she worked on the quality team. Prior to joining PBGH, she worked on reproductive health policy and the changing healthcare marketplace initiative at the Henry J. Kaiser Family Foundation. She has also consulted on health insurance coverage in the temporary employment industry and on the first statewide survey in California of MediCal beneficiaries, and worked as a community Liaison for Kaiser Permanente during the establishment of one of California's first County Organized Health Systems. She holds a PhD in public policy from the Goldman School of Public PoLicy and a MPH from the School of Public Health at the University of California, Berkeley.

Health Benefit Plans, Employee↗

Neutron flux-density and secondary-particle energy spectra at the 184-inch synchrocyclotron medical facility.

We have identified the sources of neutron production in the beam transport system of the 720-MeV helium beam used for radiation therapy at the 184-in synchrocyclotron of the Lawrence Berkeley Laboratory, and determined their magnitude. Measurements with activation detectors of differing energy response were used to unfold secondary particle spectra at various locations on the patient table. The effect of charged particles was estimated using a calculation of neutron-flux densities derived from published cross sections. The absorbed dose, as a function of distance from the beam axis, was calculated using the unfolded spectra and evaluated fluence-to-dose conversion factors. The values of absorbed dose obtained from the unfolding of experimental data agree with the values obtained from the calculated spectra within the estimated uncertainty of +/- 25%. These values are approximately 5 X 10(-3) rad on the beam axis and approximately 1 X 10(-3) rad at distances greater than 20 cm, perpendicular to the beam axis, per rad deposited by the incident alpha-particle beam in the plateau. Estimates of upper limits of dose to two critical organs, the lens of the eye and red bone marrow, are approximately 25 rad and approximately 5 rad, respectively, for a typical treatment plan.

Alpha Particles↗

Dosimetric considerations of d(15) + Be and p(26) + Be neutron beams from an isocentric cyclotron facility.

To select the optimum therapeutic neutron beam available from a CS30 medical cyclotron (manufactured by the Cyclotron Corporation, Berkeley, California), central axis depth dose data and output dose rates were compared for the bombardment of beryllium with either the proton or deuteron beams available from the machine. The effect on these parameters of filtering the beams with either pure polyethylene, polyethylene loaded with 5% boron, or polyethylene loaded with 10% lithium was studied. A 4-cm, 10% lithiated filter used with a 26-MeV proton beam was selected for therapeutic use. Buildup curves, beam profiles at several transverse planes for different field sizes, and comparison of beam profiles with 60Co are given.

Beryllium↗

A helium-ion beam for stereotactic radiosurgery of central nervous system disorders.

A new radiation beamline configuration for stereotactic heavy-ion Bragg peak radiosurgery of patients with intracranial deep arteriovenous malformations, including carotid-cavernous fistulas, has been developed using the 230 MeV/u helium ion beam at the 184-in. Synchrocyclotron at the University of California, Berkeley. The modified beam has five characteristics: uniform field between 10 and 40 mm in diameter; variable depth of penetration between 40 and 140 mm; stopping region for primary ions that can be broadened up to 40 mm; sharply defined lateral and distal borders; and dose rate greater than 2 Gy/min. It is adapted to the ISAH (irradiation stereotactic apparatus for humans) at the 184-in. Synchrocyclotron, with effective stereotactic localization of defined volumes within the brain, and is designed to reach all intracranial targets. It has proven suitable for all patients with intracranial vascular disorders treated with stereotactic radiosurgery at our laboratory.

Biophysical Phenomena↗

Characterization of fragmented heavy-ion beams using a three-stage telescope detector: measurements of 670-MeV/amu 20Ne beams.

Measurements of a 670-MeV/amu 20Ne beam at the Lawrence Berkeley Laboratory Bevalac heavy-ion accelerator with various thicknesses of water absorber were obtained with the BERKLET. The BERKLET, a simple three-stage solid-state telescope detector, has been described previously. This instrument measures the linear energy transfer (LET) and residual energy of particles, allows the identification of the particle's charge, and provides a means of obtaining LET and energy statistics for the beam, separated by particle charge. The track and dose averaged LET dependence on the amount of water absorber was determined for each species of fragment in the beam. Large numbers of low-LET particles in the fragmented beam were detected. The results of the analysis are presented followed by a discussion of the effects of multiple scattering and secondary fragmentation on the measurements. A brief discussion of the implications of the BERKLET measurements for radiobiology is also presented.

Energy Transfer↗

The multiple Coulomb scattering of very heavy charged particles.

An experiment was performed at the Lawrence Berkeley Laboratory BEVALAC to measure the multiple Coulomb scattering of 650-MeV/A uranium nuclei in 0.19 radiation lengths of a Cu target. Differential distributions in the projected multiple scattering angle were measured in the vertical and horizontal planes using silicon position-sensitive detectors to determine particle trajectories before and after target scattering. The results were compared with the multiple Coulomb scattering theories of Fermi and Molière, and with a modification of the Fermi theory, using a Monte Carlo simulation. These theories were in excellent agreement with experiment at the 2 sigma level. The best quantitative agreement is obtained with the Gaussian distribution predicted by the modified Fermi theory.

Computer Simulation↗

The effect of patient motion on dose uncertainty in charged particle irradiation for lesions encircling the brain stem or spinal cord.

A specialized charged-particle radiotherapy technique developed at Lawrence Berkeley Laboratory (LBL) is applied to patients with lesions abutting or surrounding the spinal cord or brain stem. This technique divides the target into two parts, one partially surrounding the critical structure (brain stem or spinal cord) and a second excluding the critical structure and abutting the first portion of the target. Compensators are used to conform the dose distribution to the distal surface of the target. This technique represents a novel approach in treating unresectable or residual tumors surrounding the spinal cord or brain stem. Since the placement of the patient with respect to beam-shaping devices is critical for divided-target treatments, a method for calculating dose distributions reflecting random patient motion is proposed, and the effects of random patient motion are studied for two divided-target patient examples. Dose-volume histograms and a normal-tissue complication probability model are used in this analysis. For the patients considered in this study, the normal-tissue-complication probability model predicts that random patient motion less than or equal to 0.2 cm is tolerable in terms of spinal cord complications.

Central Nervous System Neoplasms↗