Biological response to variation of acid-volatile sulfides and metals in field-exposed spiked sediments

Vertical and temporal variations of acid-volatile sulfides (AVS) and simultaneously extracted metals (SEM) in sediment can control biological impacts of metals. To assess the significance of these variations in field sediments, sediments spiked with cadmium, copper, lead, nickel, and zinc were deployed in Narragansett Bay for four months and recolonization by benthic organisms investigated. In surface sediments, concentrations of AVS decreased with time whenever AVS exceeded SEM but remained unchanged when AVS was less than SEM; in subsurface sediments, concentrations increased slightly. Concentrations of total SEM decreased with time only in surface sediments in which SEM exceeded AVS. Metals were not detected in interstitial waters of sediments where AVS exceeded SEM but were significant when SEM exceeded AVS and followed the order of solubilities of their sulfides. Concentrations in interstitial waters decreased with time, but exceeded U.S. Environmental Protection Agency chronic water quality criteria for 56 to 119 d. After 119 d, faunal assemblages in all treatments were similar to controls. Lack of biological response was related to vertical distributions of AVS and SEM. Biological exposure took place in near-surface sediments, where AVS exceeded SEM in even the highest treatments. Therefore, concentrations of metals in interstitial waters were low and consequently biological impacts were undetectable.

Derivation of temporary emergency exposure limits (TEELs)

Short-term chemical concentration limits are used in a variety of applications, including emergency planning and response, hazard assessment and safety analysis. Development of emergency response planning guidelines (ERPGs) and acute exposure guidance levels (AEGLs) are predicated on this need. Unfortunately, the development of peer-reviewed community exposure limits for emergency planning cannot be done rapidly (relatively few ERPGs or AEGLs are published each year). To be protective of Department of Energy (DOE) workers, on-site personnel and the adjacent general public, the DOE Subcommittee on Consequence Assessment and Protective Actions (SCAPA) has developed a methodology for deriving temporary emergency exposure limits (TEELs) to serve as temporary guidance until ERPGs or AEGLs can be developed. These TEELs are approximations to ERPGs to be used until peer-reviewed toxicology-based ERPGs, AEGL or equivalents can be developed. Originally, the TEEL method used only hierarchies of published concentration limits (e.g. PEL- or TLV-TWAs, -STELs or -Cs, and IDLHs) to provide estimated values approximating ERPGs. Published toxicity data (e.g. lc(50), lc(LO), ld(50) and ld(LO) for TEEL-3, and tc(LO) and td(LO) for TEEL-2) are included in the expanded method for deriving TEELs presented in this paper. The addition here of published toxicity data (in addition to the exposure limit hierarchy) enables TEELs to be developed for a much wider range of chemicals than before. Hierarchy-based values take precedence over toxicity-based values, and human toxicity data are used in preference to animal toxicity data. Subsequently, default assumptions based on statistical correlations of ERPGs at different levels (e.g. ratios of ERPG-3s to ERPG-2s) are used to calculate TEELs where there are gaps in the data. Most required input data are available in the literature and on CD ROMs, so the required TEELs for a new chemical can be developed quickly. The new TEEL hierarchy/toxicity methodology has been used to develop community exposure limits for over 1200 chemicals to date. The new TEEL methodology enables emergency planners to develop useful approximations to peer-reviewed community exposure limits (such as the ERPGs) with a high degree of confidence. For definitions and acronyms, see Appendix.

Comparative toxicity of fluoranthene to freshwater and saltwater species under fluorescent and ultraviolet light

The acute and chronic toxicity of fluoranthene was determined for a diverse group of freshwater and saltwater species under both standard laboratory fluorescent light and ultraviolet (UV) light test conditions. Acute tests with 21 species demonstrated that fluoranthene was not lethal within its water solubility limit to most species tested under fluorescent light, but was lethal well below this limit to nearly all of the species tested under UV light. In general, the acute sensitivity of freshwater and saltwater species from the same class was similar, although UV light exposure changed the relative sensitivity of some species. Crustaceans were the most sensitive to fluoranthene, but in the presence of UV light, an oligochaete and a fish were the most sensitive. Overall, UV light increased acute fluoranthene toxicity approximately one to three orders of magnitude. In chronic tests, sublethal concentrations of fluoranthene were toxic under both fluorescent and UV light, but as in most acute tests, UV light increased chronic toxicity approximately an order of magnitude. Comparison of data from tests conducted in the laboratory and outdoors demonstrated that acute toxicity increased with increased UV light intensity.http://link. springer-ny.com/link/service/journals/00244/bibs/37n4p496.++ +html</HEA

Recommended default methodology for analysis of airborne exposures to mixtures of chemicals in emergencies

Emergency planning and hazard assessment of Department of Energy (DOE) facilities require consideration of potential exposures to mixtures of chemicals released to the atmosphere. Exposure to chemical mixtures may lead to additive, synergistic, or antagonistic health effects. In the past, the consequences of exposures to each chemical have been analyzed separately. This approach may not adequately protect the health of persons exposed to mixtures. This article presents default recommendations for use in emergency management and safety analysis within the DOE complex where potential exists for releases of mixtures of chemicals. These recommendations were developed by the DOE Subcommittee on Consequence Assessment and Protective Actions (SCAPA). It is recommended that hazard indices (e.g., HIi = Ci/Limiti, where Ci is the concentration of chemical "i") be calculated for each chemical, and unless sufficient toxicological knowledge is available to indicate otherwise, that they be summed, that is, sigma i(n) = 1HIi = HI1 + HI2 + ... + HIn. A sum of 1.0 or less means the limits have not been exceeded. To facilitate application of these recommendations for analysis of exposures to specific mixtures, chemicals are classified according to their toxic consequences. This is done using health code numbers describing toxic effects by target organ for each chemical. This methodology has been applied to several potential releases of chemicals to compare the resulting hazard indices of a chemical mixture with those obtained when each chemical is treated independently. The methodology used and results obtained from analysis of one mixture are presented in this article. This article also demonstrates how health code numbers can be used to sum hazard indices only for those chemicals that have the same toxic consequence.

Evaluation of state efforts to improve systems of care for children and adolescents with severe emotional disturbances: the CASSP (Child and Adolescent Service System Program) initial cohort study

In 1984, the National Institute of Mental Health (NIMH) began funding its Child and Adolescent Service System Program (CASSP). In this paper, we present findings from a descriptive study of the experiences of the initial cohort of states to receive CASSP grants, conceived and conducted when the projects were approaching the end of their fifth and final year of NIMH funding. Detailed case studies were conducted of each of the 10 initial cohort projects, and the findings analyzed across projects. Data were collected from three major sources: (1) existing documentation about the projects, (2) site visits to each of the projects, and (3) information from relevant secondary sources. Findings suggest that the initial cohort projects utilized a variety of strategies and encountered a variety of barriers and facilitating factors. The projects generally implemented the intended CASSP program and did so by using a variety of strategies. The projects were judged by stakeholders in their states to have influenced the service systems in their states in the intended directions: toward a more comprehensive system of care that emphasizes community-based treatment; toward better integrated, more collaborative efforts among the state agencies involved; toward a more detailed understanding on the part of system stakeholders of the mental health problems of children and adolescents who have severe emotional disturbances, and of the influence of those problems on the lives of the children and their families; and toward increased involvement by parents and other family members in the care of these children and adolescents.

DOE emergency planning & emergency management using emergency response planning guidelines (ERPGS) and temporary emergency exposure levels (TEELs)

Facilities within the Department of Energy community perform emergency management to conform with Federal regulations, internal guidance and good management practice. Emergency management in this context includes hazard analysis, consequence assessment, and development of emergency plans including protective actions for workers, uninvolved workers, and the general public. ERPGs are used as the action level for decision making with regards to accidental chemical releases; AEGLs are also being developed for that purpose. DOE actively participates in the development of ERPGs and AEGLs, however, there is a time gap inherent in the development of community exposure limits (which can be months or years) and the need for community exposure limits (which must be implemented now). In recognition of this problem, the DOE Subcommittee on Consequence Assessment and Protective Actions (SCAPA) has developed a hierarchy of alternate exposure limits (Temporary Emergency Exposure Limits, TEELs) to use as temporary guidance for emergency planning for those chemicals for which an ERPG or an AEGL does not exist. This presentation will discuss DOE's involvement in development of ERPGs and AEGLs, including their application, and will discuss the development and use of TEELs (including advantages and disadvantages).

Influence of information related to child physical abuse on professional ratings of adjustment and prognosis

The study investigates the influence of access to information of a history of physical maltreatment on the evaluative responding of social service and clinical psychology professionals. Written vignettes were used in a 2 x 2 x 2 factorial design to manipulate the: (a) presence/absence of abuse history; (b) presence/absence of behavior problems; and (c) gender of the child. Professionals rated children presented in 12 case vignettes along five treatment-related dimensions: (a) overall adjustment; (b) predicted 6 months temporal stability of behavior; (c) likelihood of treatment referral; (d) expected home intervention success; and (e) expected school intervention success. Four dimensions related to social functioning were also rated, including likelihood of the child being: (a) recommended to serve as assistant to teacher; (b) elected as a school activity team leader; (c) elected as a class officer; and (d) nominated as a candidate for successful completion of a summer camp program. The findings verified the influence of information related to a history of maltreatment of professional judgments, despite matched vignette content for all factors other than maltreatment status. The results suggests a possible failure to recognize that some children have been buffered from the negative effects of abuse and point to the risk of erroneous judgments that may be directed toward maltreated children.

The influence of case and professional variables on identification and reporting of physical abuse: a study with medical students

Identification and reporting of suspected cases of maltreatment are important precursors to intervention, as maltreating parents typically do not self-refer for treatment. Professionals from various disciplines are legally mandated to report suspected cases of child maltreatment, yet incidences of abuse can remain unidentified or unreported. Identification of physical abuse often depends on careful consideration of the characteristics of the injuries and the plausibility of the explanations provided for the injuries. Many variables impact identification, as well as the subsequent decision of whether or not to report the case if abuse is suspected. The study examined the influence of three case variables (injury severity, plausibility of explanation, and time to seek medical attention) and two professional variables (gender of subject and amount of clinical experience) on how medical students respond to hypothetical cases of abuse. As part of the study, the responses of medical students were compared to those of practicing physicians. Subjects evaluated 16 different vignettes, each describing an injured child, rated whether injuries may have resulted from physical abuse, and indicated what further action should be taken with the case, including whether it should be reported. Results indicated a significant three-way interaction between injury severity, injury explanation, and delay. Subject gender and amount of clinical experience did not influence identification. Significant positive correlations between identification and reporting were found. Correspondence between the responses of medical students and physicians was quite strong. Implications for clinical training of mandated reporters and directions for future research are discussed.

Reconsideration of the use of peer sociometrics for evaluating social-skills training. Implications of an idiographic assessment of temporal stability

Social-skills training studies using sociometric procedures as dependent measures have often yielded mixed results as to the improvement of the subjects. Failure to document improvement in peer acceptance subsequent to behavior change has led some to question the validity of social-skills interventions, whereas others have questioned the psychometric properties of the measures themselves. This study examined the temporal stability of the two major types of peer measures used in social-skills interventions studies; peer-nomination measures of liking and peer-rating measures of liking. Subjects were 87 children in three fourth-grade and two fifth-grade classrooms. Temporal stability was assessed across time intervals of 2,6, and 8 weeks. Temporal stability was examined as it traditionally has been at the group level (using Pearson product-moment correlations), and at the level at which data are normally examined for change in social-skills interventions, at the level of the individual child (using phi and Cramer's V coefficients). Assessed at the group level, the three types of peer measures were generally moderately to highly stable. Stability coefficients for individual children's scores on the peer measures, however, indicated instability at the level of the individual child. These problems regarding stability at the individual, idiographic level may be especially relevant when sociometric procedures are used as dependent measures in individual subject design studies. Conceptual and practical implications of the findings for the assessment of social-skills interventions are discussed.

Use of Biota-Sediment Accumulation Factors to Assess Similarity of Nonionic Organic Chemical Exposure to Benthically-Coupled Organisms of Differing Trophic Mode

The U.S. Environmental Protection Agency is in the process of developing Sediment Quality Criteria (SQC) to specify the acceptable degree of risk from sediment-mediated chemical exposure for the protection of benthically-coupled organisms. In this study, potential differences in chemical exposure for benthic organisms of differing habitats or feeding types were evaluated through the use of Biota-Sediment Accumulation Factors (BSAFs). It was hypothesized that If species of different habitats have similar exposures, then the BSAF values should not be different. The BSAFs are calculated using the concentrations of chemicals in an organism (&mgr;g/g lipid) divided by the concentrations of the same chemicals in sediment (&mgr;g/gOC). Data from both freshwater and saltwater studies that met specified criteria for data quality were obtained from published papers or reports. These included three laboratory and five field studies containing 27 species and 4054 BSAF values. The BSAFs were intercompared for similarity of central tendency as grouped by chemical class (PCBs, PAHs, pesticides), individual species, and species grouped by habitat (infaunal deposit feeder, scavenger, filter feeder, and benthically-coupled fish). Plots of BSAFs grouped by class and KOW revealed that the BSAFs for the PAHs were uniformly lower (mean 0.34) than the PCB (1.03) or pesticide (1.36) classes. For the PCBs, the BSAFs for all species exhibited a KOW dependency with decreased bioaccumulation evident above and below the range of 5.99-7.27 log10 KOW. In order to optimize the detection of species/habitat differences in the BSAFs, further analyses were segregated by chemical class and excluded PCB data outside the above KOW range. These analyses revealed similar BSAF values for various species both within and among habitat groups, and indicated that the sum total of exposures from all routes is similar across species. This similarity of chemical exposure across benthic species, and the similarity of sensitivities between benthic species and species used to derive WQC FCVs supports the applicability of SQC for all benthic organisms as a group.

The identification and reporting of physical abuse by physicians: a review and implications for research

Identification and reporting of possible cases of child physical abuse are critical precursors to intervention with maltreating families. Professionals from a variety of disciplines are mandated to report suspected cases of child maltreatment. Unfortunately, not all physically abused children are identified or reported. This paper reviews the literature that has examined factors that may influence the identification and reporting of physical abuse by physicians. The literature review is preceded by an overview of the multistep, multibehavior process of identification and reporting. The factors that may influence identification and reporting are discussed according to their association with the case, physician, or setting. Future directions for research in the area of identification and reporting are suggested throughout the paper.

[Dental amalgam: a toxicological evaluation]

During the latest decades the use of dental amalgam has been discussed with respect to potential toxic effects of the mercury component. In order to evaluate potential risks from this practice the recent literature is reviewed. Corrosion of fillings results in liberation of mercury. The absorption from this source in the Danish population can be estimated to be one to five micrograms/24 hrs. This exposure level is far below that accepted in occupational exposure and far below the minimum toxic level. Investigation of placental transfer of mercury has not provided any reason to avoid using amalgam during pregnancy. Micromercurialism or metal syndrome is claimed to be related to amalgam fillings. This syndrome consists mainly of complaints from the central nervous system, but also from muscles, joints and the gastrointestinal tract. The symptoms are non-specific and the documentation of the existence of such a syndrome related to mercury exposure is weak. The symptoms reported can be due to other chemical exposures, but psycho-social conditions may also play an important role. Information on disappearance of symptoms after removal of fillings may be a result of a placebo effect, which may be suggested until controlled experiments are performed. For this reason the use of chelating therapy is not indicated. Allergic contact eczema observed in few individuals is the only problem documented in connection with the use of amalgam fillings.

Social-skills interventions with adolescents. Current issues and procedures

During adolescence, the interpersonal interactions and behaviors necessary for successful social functioning become increasingly complex. In recent years, social-skills training with adolescents has made a variety of advances beyond basic skill acquisition toward techniques designed to promote generalization and maintenance of an effective interpersonal repertoire. This article reviews relevant empirical literature for current issues and procedures in social-skills training with adolescents, including use of social-skills interventions for a variety of adolescent populations and problems, use of innovative and promising intervention procedures, and issues regarding generalization and social validity of intervention procedures.

Long-term consequences of childhood physical abuse

This article reviews the literature on the long-term consequences of childhood physical abuse. Empirical research is discussed within 7 topic areas: aggressive and violent behavior, nonviolent criminal behavior, substance abuse, self-injurious and suicidal behavior, emotional problems, interpersonal problems, and academic and vocational difficulties. The studies reviewed involve primarily adult populations, although pertinent findings from literature on children and adolescents are briefly summarized. Some variables that affect the relation between physical abuse and long-term consequences are examined. These moderator variables include maltreatment characteristics, individual factors, family factors, and environmental factors. The article ends with suggestions for future research on long-term consequences and variables that may affect these outcomes.

Relations between social skills and high-risk sexual interactions among adolescents. Current issues and future directions

Researchers have begun to employ social-skills training in efforts to change the sexual behavior of adolescents. However, despite the promise of social-skills training, little is known about how social skills are related to the sexual practices of adolescents. The present article reviews the current literature and proposes a conceptual framework for understanding the relations between social skills and sexual behavior of adolescents by (a) examining the relationship between sexual activity and social skills, (b) examining the development of sexual-interaction skills and deficits, (c) summarizing what is currently known about the relations between social skills and sexual behavior, (d) discussing current issues in the assessment and treatment of sexual-interaction skills deficits, and (e) proposing some directions for needed research that will add both to our current knowledge base and to the effectiveness of applied intervention efforts.

Patterns of appraisal and coping across different stressor conditions among former prisoners of war with and without posttraumatic stress disorder

Little is known about how survivors of extreme events cope with traumatic memories and subsequent negative life experiences. The present study compared (a) repatriated prisoners of war (RPWs) from World War II (WW II) with chronic posttraumatic stress disorder (PTSD), (b) RPWs without PTSD, and (c) noncombat veterans on measures of general psychological functioning, appraisal, and coping. Appraisal and coping were assessed under 2 stressor conditions: memories of war/captivity and recent negative life events. RPWs with PTSD reported poorer general psychological functioning; significantly less control over memories of WW II: and more frequent use of self-isolation, wishful thinking, self-blame, and social support in an effort to cope with these memories than did the 2 comparison groups. Fewer between-groups differences were found for the recent stressor condition. Findings are discussed in terms of factors that may explain the perseverance of coping difficulties associated with PTSD.

Effectiveness of a peer-helper intervention to increase children's social interactions. Generalization, maintenance, and social validity

Peer-mediated interventions are being used increasingly with a variety of populations. This study examined the impact of a peer-helper intervention on the low rates of prosocial interactions of three-elementary-school children. Two peers from each child's classroom were trained as helpers to increase the social interactions of the socially isolated children. A multiple-baseline across-subjects design was used to demonstrate the impact of the intervention, and a within-subject A-B-A withdrawal design was used to assess maintenance. Behavioral observations during recess periods indicated that positive interactions with peer helpers and other classmates increased during intervention and were maintained in withdrawal and follow-up phases. Increases in positive interactions generalized to a second recess setting in which the peer-helper intervention was not introduced. The positive social interactions of all subjects reached social-validation levels of comparison groups of peers in the observation settings. Classroom sociometric assessment and teacher and self-report measures provided variable support for the effectiveness of intervention.

Patterns of appraisal and coping across different stressor conditions among former prisoners of war with and without posttraumatic stress disorder

Little is known about how survivors of extreme events cope with traumatic memories and subsequent negative life experiences. The present study compared (a) repatriated prisoners of war (RPWs) from World War II (WW II) with chronic posttraumatic stress disorder (PTSD), (b) RPWs without PTSD, and (c) noncombat veterans on measures of general psychological functioning, appraisal, and coping. Appraisal and coping were assessed under 2 stressor conditions: memories of war/captivity and recent negative life events. RPWs with PTSD reported poorer general psychological functioning; significantly less control over memories of WW II: and more frequent use of self-isolation, wishful thinking, self-blame, and social support in an effort to cope with these memories than did the 2 comparison groups. Fewer between-groups differences were found for the recent stressor condition. Findings are discussed in terms of factors that may explain the perseverance of coping difficulties associated with PTSD.

Behavioral assessment of child-abusive and neglectful families. Recent developments and current issues

Recent developments and current issues in the behavioral assessment of child-abusive and neglectful families are described. Procedures for the assessment of target behaviors in a variety of areas that may be related to the occurrence of further maltreatment and improved family functioning are reviewed. The primary emphasis is on measures recently developed for maltreating populations, although some measures discussed were developed for nonmaltreating populations. A variety of issues that commonly arise in the assessment of maltreating families and future directions for practice and research are also addressed.

Habits with potential as disorders. Prevalence, severity, and other characteristics among college students

Little is known about the prevalence of the various habit disorders-such as pulling out one's hair, biting fingernails, or grinding teeth--and even less is known about the prevalence of lesser habits which, if exacerbated, may be costly enough to an individual to be labeled a disorder. Such superficially "purposeless" behaviors provided the focus of the present investigation. An initial group of 142 college students completed a pilot questionnaire to identify habits to be included in a survey. The final questionnaire was then administered to 286 college students. It asked about "purposeless habits," defined as those "repeated actions that appear to serve no useful purpose but that we continue to engage in anyway." Behaviors included habits involving the mouth, face, neck, fingers, hands, legs, hair, body, clothing, and objects. In addition to assessing the nature and severity of problems caused by each habit, the stimulus conditions influencing its probability, related behaviors, and attempts to stop the habit were assessed. The kinds of behaviors that could become habit disorders were found to be quite common. Clinical and theoretical implications of the results are discussed.

Group conversational-skills training with inpatient children and adolescents. Social validation, generalization, and maintenance

Two groups of inpatient youths (n = 4 and n = 5) received group conversational-skills training. Conversational component behaviors of both groups at baseline were compared to the behaviors of normal youth from the community. For each inpatient group, component behaviors on which they were most discrepant from normal youths were selected for training. Multiple-baseline designs across component behaviors were used and patients were trained to socially-validated criterion levels. Effectiveness of training was demonstrated through (a) behavioral ratings during dyadic, unstructured conversations with other members of their group, (b) behavioral ratings during conversations with unfamiliar nonpsychiatric persons, (c) global ratings of conversational effectiveness by nonpatient peers, (d) generalization to in vivo conversations, and (e) maintenance of improvement at 1- and 3-month follow-up assessments. Results were replicated across both groups and indicated that training effects were socially validated, generalized to conversations with unfamiliar persons and to in vivo conversations, and maintained over time.

A peer-mediated intervention with clinic-referred socially isolated girls. Generalization, maintenance, and social validation

Peer-mediated interventions have been widely employed with seriously impaired autistic and handicapped children to modify social withdrawal. This study extends the literature by examining the impact of a peer intervention on the interactions of developmentally normal, socially isolated girls. Two to three actual classroom peers were trained to serve as helpers to initiate and maintain interactions with the subjects. The intervention was introduced sequentially across 2 girls in a multiple-baseline design, and a within-subject ABA withdrawal design was used to assess maintenance. Behavioral observations during recess periods indicated that both children's positive social interactions with peer helpers and other classmates were increased significantly during intervention and were maintained in return-to-baseline conditions and at 4-month follow-up. Increases in positive social interactions of both subjects generalized to a second recess setting, in which intervention was not introduced. Subjects' interactions in both recess settings reached levels comparable to those of social-comparison groups of peers. Teacher and self-report ratings suggested that both girls had fewer social problems and experienced less loneliness and dysphoria as a result of the intervention.

Conversational skills of inpatient conduct-disordered youths. Social validation of component behaviors and implications for skills training

The conversational skills of 24 inpatient conduct-disordered youths and 32 "normal" youths from the community were assessed and compared. A panel of 12 peer judges provided global ratings of subjects' conversational skill. Moderate to high amounts of the variance in the peer ratings were accounted for by conversational-skill component behaviors, especially for the inpatient conduct disordered youths. Compared to the nonpatient youths, the inpatient youths were significantly deficient in their use of a variety of conversational-skill component behaviors and received significantly lower peer ratings of conversational skill. Implications of the findings for social-skills training and research are discussed.

The influence of task and location on solvent exposures in a printing plant

A work measurement technique was used to monitor the activities of seven printing press operators. Repeated observations were made to learn workers' tasks and workers' locations in the plant, and a photoionization detector was used to measure the instantaneous solvent concentration in each worker's breathing zone. Location data, analyzed using a computer aided design system, did not show any indication that there were high or low exposure areas. Regression, however, showed that a significant amount of variability in a worker's exposures was accounted for by the number of times the worker performed a certain "hazardous task" (r2 = 0.57). The results indicate that it may be possible to simplify industrial hygiene sampling strategies by using work measurement data, such as time study or work sampling, to identify maximum risk employees.

Distribution and ultrastructure of neurons in opossum piriform cortex displaying immunoreactivity to GABA and GAD and high-affinity tritiated GABA uptake

GABAergic neurons have been identified in the piriform cortex of the opossum at light and electron microscopic levels by immunocytochemical localization of GABA and the GABA-synthesizing enzyme glutamic acid decarboxylase and by autoradiographic visualization of high-affinity 3H-GABA uptake. Four major neuron populations have been distinguished on the basis of soma size, shape, and segregation at specific depths and locations: large horizontal cells in layer Ia of the anterior piriform cortex, small globular cells with thin dendrites concentrated in layers Ib and II of the posterior piriform cortex, and multipolar and fusiform cells concentrated in the deep part of layer III in anterior and posterior parts of the piriform cortex and the subjacent endopiriform nucleus. All four populations were well visualized with both antisera, but the large layer Ia horizontal cells displayed only very light 3H-GABA uptake, thus suggesting a lack of local axon collaterals or lack of high-affinity GABA uptake sites. The large, ultrastructurally distinctive somata of layer Ia horizontal cells receive a very small number of symmetrical synapses; the thin, axonlike dendrites of small globular cells are exclusively postsynaptic and receive large numbers of both symmetrical and asymmetrical synapses, in contrast to somata which receive a small number of both types; and the deep multipolar and fusiform cells receive a highly variable number of symmetrical and asymmetrical synapses on somata and proximal dendrites. Labeled puncta of axon terminal dimensions were found in large numbers in the neuropil surrounding pyramidal cell somata in layer II and in the endopiriform nucleus. Moderately large numbers of labeled puncta were found in layer I at the depth of pyramidal cell apical dendrites with greater numbers in layer Ia at the depth of distal apical segments than in layer Ib. High-affinity GABA uptake was demonstrated in the termination zone of the projection from the anterior olfactory nucleus to the anterior piriform cortex. Cell bodies of origin of this projection displayed heavy retrograde labeling with 3H-GABA. Matching neuropil and cellular labeling was demonstrated with the GABA-BSA antiserum but not with the GAD antiserum, thus suggesting that GABA is normally present in these cells but is taken up from the neuropil rather than synthesized. No comparable high-affinity GABA uptake was demonstrated in the association fiber systems that originate in the piriform cortex.(ABSTRACT TRUNCATED AT 400 WORDS)

Respiratory symptoms associated with the use of azodicarbonamide foaming agent in a plastics injection molding facility

Respiratory health variables were studied cross-sectionally in 227 employees of a plastics molding facility where numerous complaints had been apparently associated with the use of azodicarbonamide foaming agent in injection molding. Pre- and postshift respiratory status measures and azodicarbonamide concentrations were also obtained for 17 employees. Cross-sectional pulmonary function differences by injection molding status were not observed. Modest decrements in pulmonary function measures were observed between start and end of shift but with no dose-effect relationship. A strong association was observed for injection molding workers for eye/nose/throat irritation, cough, and wheezing. Additionally, wheezing, chest tightness, and symptoms of chronic bronchitis were strongly associated with work in injection molding during periods in which azodicarbonamide was in use. These results suggest respiratory symptom causation by some combination of azodicarbonamide itself, reaction products of azodicarbonamide formed during injection molding, or other unidentified agents uniquely associated with the process of injection molding with azodicarbonamide foaming agent.

An inventory to measure staff knowledge of behavioral methods with inpatient children and adolescents

A 35-item multiple choice inventory to assess inpatient staff's knowledge of behavioral methods with children and adolescents is described. The instrument appears to possess satisfactory content validity for basic behavioral principles and good internal consistency and reliability. It appears useful for research and staff inservice educational assessment in inpatient treatment settings where a measure of this type in needed. The inventory may also be useful in identifying newly employed staff who may benefit from behavioral training before assuming direct services roles on inpatient wards.

Computerized spirometry using a portable microcomputer

The reliable conduct of pulmonary function studies, while in the field, is increasingly important as various standards mandate this activity. Versatile, portable and accurate equipment is required. A lightweight and computerized portable spirometer system is discussed, PSPIRO, which uses a standard volumetric spirometer and a briefcase-sized microcomputer. The system, compact enough to be easily moveable by one person, performs tests for FVC, FEV(1), FEV(3), the percentage of predicted pulmonary function for each, and the ratio of FEV(1)/FVC. Back extrapolation is used to establish the start of each forced expiratory maneuver, reproducibility checks are performed, and accuracy is within acceptable epidemiologic standards. A small, portable analog to digital interface (PLAD) was developed for performing A/D conversions through the RS-232C port of the portable microcomputer.

Stress management training for dental students

Dental school and professional practice are well-documented sources of stress. Although students and dentists risk developing stress-related disorders, no empirically evaluated method for helping dental students cope with stress has been reported. A group of 17 dental students participated in a six-session program that included instruction in self-relaxation and time management; exercise and leisure planning; and cognitive modification techniques. From pre- to post-training, subjects showed improvement on a variety of self-report and physiological measures relative to a waiting-list control group. A three-month follow-up assessment revealed continued reductions in stress-related behavior. The importance of stress-management training for dental students is discussed as well as suggestions for future research.

Earplugs--a computer program for simulation of personal hearing protection devices

Earplugs is a program to allow predictive evaluation of earplugs and earmuffs. Written in Basic for the Apple II+, it is translatable into all other versions of Basic. The program allows the user to compare the attenuation capabilities of any earplug versus the environmental octave band analysis for the workplace in question. This version of the program provides a plot of the results.

Computer assisted spirometry

Three of the most popular microcomputers, the TRS-80 Model I, the APPLE II+, and the IBM Personal Computer were connected to a spirometer for data acquisition and analysis. Simple programs were written which allow the collection, analysis and storage of the data produced during spirometry. Three examples demonstrate the relative ease for automating spirometers.

Endrin: effects on the entire life cycle of a saltwater fish, Cyprinodon variegatus

The sheepshead minnow (Cyprinodon variegatus) was continuously exposed for 23 wk to the organochlorine insecticide endrin, from the embryonic state through hatching until adulthood and spawing. The resultant progeny were monitored to determine the effects of the toxicant on their survival, growth, and reproduction. Average measured exposure concentrations were O (control), 0.027, 0.077, 0.12, 0.31, and 0.72 microgram/liter. Embryos exposed to 0.31 and 0.72 microgram/liter hatched early; all fry exposed to 0.72 microgram/liter died by day 9 of exposure. At 0.31 microgram/liter, fry were initially stunted and some died. Survivors seemed unaffected until maturity, when some females died during spawning; fewer eggs were fertile and survival of exposed progeny decreased. No significant effects were observed th roughout this fish's life cycle at an exposure concentration of 0.12 microgram/liter. Four-week-old juvenile fish accumulated 2,500 times the concentration of endrin in the exposure water; adults, 6,400 times; and their eggs, 5,700 times. The specific application factor (calculated by dividing the limits on the maximum acceptable toxicant concentration, greater than 0.12 and less than 0.31 microgram/liter, by the concentration lethal to 50% of the juvenile fish in 96 hr, 0.34 microgram/liter) ranged from 0.35 to 0.91. To our knowledge this is the first toxicity test carried out through the entire life cycle of an oviporous esturarine fish. Data from this experiment and from experiments with another estuarine fish and four freshwater fish all demonstrate that there is little difference between endrin concentrations that produce acute effects and concentrations that do not affect the fish in chronic exposures lasting four or more weeks.

Chlordane: effects on several estuarine organisms

Dynamic marine toxicity tests were performed with technical grade chlordan and eastern oysters (Crassostrea virginica), pink shrimp (Penaeus duorarum), grass shrimp (Palaemonetes pugio), sheepshead minnows (Cyprinodon variegatus), and pinfish (Lagodon rhomboides). The 96-hr LC20S (and 95% confidence limits) based on measured concentrations of chlordane (in mug/liter) are: ping shrimp 0.4 (0.3-0.6); grass shrimp, 4.8 (4.0-6.0); sheepshead minnows, 24.5 (19.9-28.6); and pinfish, 6.4 (5.0-7.3). The 96-hr EC50 for eastern oysters was 6.2 (4.8-7.9). In a flow-through test, embryos and fry of sheepshead minnows were exposed to average measured concentrations of chlordane from 1.3 to 36.0 mug/liter for 28 days. Neither fertilization success nor embryo survival was affected by the concentrations of chlordane to which these life stages were exposed. However, sheepshead minnow fry did not survive for more than 10 days in chlordane concentrations greater than 7.1 mug/liter.

Light and electron microscopy localization of chloride ions in cells of Salicornia pacifica var. utahensis

Light and electron microscopy was used to determine the distribution of chloride ions in cells and tissues of Salicornia pacifica Standl, var. utahensis (Tidestrom) Munz. Chlorenchyma cells with chloroplasts around the periphery and sclereid-like cells with distinct wall thickenings which extended from the anastomosing vascular system to near the epidermis were present in the cortex. The vascular bundles or stelar strands were surrounded by several layers of large parenchyma cells. Tissues were treated with silver acetate for silver chloride precipitation. Silver chloride precipitation sites were present in all cell types. Precipitation sites were readily evident in the vacuoles but not in other organelles.

Ethylene-induced Tropism of Trifolium fragiferum L. Stolons

The hypothesis that ethylene regulates prostrate stem growth was investigated using stolons of strawberry clover (Trifolium fragiferum L. var. Salina). Stolons became erect when treated with ethylene or 2-chloroethylphosphonic acid. Curvature was visibly detectable 2 hours after ethylene treatment, and subsequent stem elongation was rapid. Indoleacetic acid application to prostrate stolons caused only a small transitory curvature persisting less than 48 hours. Indoleacetic acid-stimulated curvature was accompanied by an increase in ethylene evolution. When stolon curvature was induced by placing strawberry clover plants in darkness or by applying gibberellic acid, ethylene production did not parallel stolon curvature.

Uptake and fate of Di-2-ethylhexyl phthalate in aquatic organisms and in a model ecosystem

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HYDROGEN OVERPOTENTIAL ON ALUMINUM

The hydrogen overpotential of pure and impure aluminum in 0.1 N H2SO4 at 25° has been studied. The effect of the autocorrosion of the metal has been interpreted and the role of impurities in determining the overpotential and the rest potential has been shown. As well, the build-up and decay of the overpotential has been studied; the behavior is much more complicated than that of noble metals.