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After 11·5 ka of quiescence (24·5–13 ka), the Nevado de Toluca volcano started a 2500 year period of activity. This period was characterized by a dome destruction event at 13 ka, a small Plinian event at 12·1 ka, and a large Plinian eruption at 10·5 ka. About 10 km3 of magma was erupted that was homogeneous in composition (63·3–65·7 SiO2 wt % whole-rock) and in mineralogy. Pumice consists of plagioclase (An30–59) > orthopyroxene (En56–59) > hornblende ≫ Fe–Ti oxides + rare apatite (in opx) + biotite, set in a rhyolitic matrix (72–76 SiO2 wt %). 40Ar/39Ar analysis of single biotite crystals yielded ages (0·81–4·7 Ma), that do not correspond to eruption ages. The biotite represents partially assimilated xenocrysts, which could have resided in the magma for only a short period of time. Mineral chemical data, coupled with hydrothermal experiments, indicate that prior to eruption the dacitic magma stagnated at a depth of 4·5–6 km below the summit at water pressures of 160–210 MPa and a temperature of 824 ± 12°C on the basis of Fe–Ti oxide thermometry, and under water-saturated conditions. To stabilize a homogeneous magma body of >10 km3 at 824°C in the upper crust, we propose that reheating of the dacitic reservoir by hotter magma batches was able to maintain the equilibrium between the temperature of the magma and the assimilation of wall-rock over a period of 2500 years. Based on similarities among the juvenile products, we suggest that the three eruptions were fed from the same magma body. [ABSTRACT FROM AUTHOR]

Post-caldera eruptions of Santorini, Greece, over the past 3000 years resulted in the formation of the Kameni Islands, which comprise a series of compositionally similar dacitic lava flows. Each lava flow has a distinct population of partially-crystalline mafic enclaves, which we propose were derived from the break-up of a layer of replenishing magma responsible for triggering the eruption. Five of the recent flows (erupted in 1570, 1939, 1940, 1941 and 1950) include enclaves of essentially identical andesitic bulk compositions, which formed by crystallization of originally aphyric melts prior to eruption. Detailed examination of angles subtended at the junctions between pairs of plagioclase grains demonstrates that enclaves from each flow have a characteristic textural signature, with distinct differences in the extent of quench-related modification of the original population of dihedral angles formed by impingement of growing grains. These variations suggest that the temperature difference between the host dacite and the replenishing andesite at the time of layer overturn and eruption differed between flows. The uniformity of major element compositions of both the replenishing magma and the host dacitic lava flows demonstrates that the critical parameter in determining the timing of layer-overturn is the pre-eruptive H2O content of both host dacite and replenishing magma. We suggest that the replenishing magma responsible for two of the three eruptions in the period 1939-1941 was significantly wetter than that responsible for the later 1950 eruption. The enclaves with the least amount of quench-related modification occur in the 1570 flow. We suggest that in this case the intruding magma was relatively dry. [ABSTRACT FROM AUTHOR]

This paper describes the process of two groups of students from high schools located in the immediate vicinity of the World Trade Center grappling to make sense of the events of September 11 through the creation of a documentary chronicling their experiences. The process of creating these videos mirrored the process and curative factors of a psychotherapy group in a non-stigmatizing, innovative, and accessible format, one generated by the students themselves with the assistance of professionals in the visual and performing arts. After reviewing the literature on the potential impact of violence on adolescents and the use of group treatment, especially in school settings, as an optimal choice for this population, we describe the distinctive process of the two separate groups of students, each culminating in different expressions of their very personal experience of September 11. We understand and contextualize their process through the lens of the therapeutic dynamics and elements of group work. [ABSTRACT FROM AUTHOR]

This article presents an integrated conceptual framework that contextualizes exposure to community violence and the interpersonal and interdependent processes of parent and child response to community violence. This model posits that parental distress, including post-traumatic stress disorder (PTSD) and depression, is a significant mediator of child distress symptomatology and behavior problems. The model advances understanding of the impact of community violence in the lives of parents and children through various mechanisms, including social capital. This article underscores the need for a fundamental shift in the study of community violence, in the delivery of mental health services, and in prevention efforts from focusing on the individual child to concentrating on the parent, family, and community-level facto rs and processes. This article highlights important areas to address in future research, including investigation and specification of the mechanisms and processes by which neighborhoods affect and influence human development outcomes. [ABSTRACT FROM AUTHOR]

The education of many Latino youth residing in urban communities is often hindered by fear of crime and violence occurring in places where they live and attend school. Addressing these concerns, this study tested a path model predicting school engagement that included neighborhood and school environment variables (e.g., neighborhood youth behavior, neighborhood safety, and school safety) and social support variables (e.g., teacher support, friend support, parent support, and neighbor support). A total of 226 Latino youth from an urban middle school in the northeastern United States participated in the study. The hypothesized model was found to fit data from the sample and showed direct effects of teacher support, friend support, and parent support on school engagement. In addition, neighborhood youth behavior and neighborhood safety influenced school engagement indirectly through its effect on social support variables. Implications for school-based interventions are discussed. [ABSTRACT FROM AUTHOR]

Arc magmas and the continental crust share many chemical features, but a major question remains as to whether these features are created by subduction or are recycled from subducting sediment. This question is explored here using Th/La, which is low in oceanic basalts (<02), elevated in the continents (>025) and varies in arc basalts and marine sediments (009034). Volcanic arcs form linear mixing arrays between mantle and sediment in plots of Th/La vs Sm/La. The mantle end-member for different arcs varies between highly depleted and enriched compositions. The sedimentary end-member is typically the same as local trench sediment. Thus, arc magmas inherit their Th/La from subducting sediment and high Th/La is not newly created during subduction (or by intraplate, adakite or Archaean magmatism). Instead, there is a large fractionation in Th/La within the continental crust, caused by the preferential partitioning of La over Th in mafic and accessory minerals. These observations suggest a mechanism of fractionation & foundering, whereby continents differentiate into a granitic upper crust and restite-cumulate lower crust, which periodically founders into the mantle. The bulk continental crust can reach its current elevated Th/La if arc crust differentiates and loses 2560% of its mafic residues to foundering. [ABSTRACT FROM AUTHOR]

Purpose - Traditional notions of culture have become unicorns: assumed creatures of the past, whose authenticity seems increasingly doubtful. It is required of us to rethink the boundaries of culture and social science; to develop our understanding of interdependency and instability in cultural life. In order to incorporate possible discourses, the practice of research must also change. This paper discusses some problems associated with ethnography in global cultures. Design/methodology/approach - I begin by presenting a brief history of ethnography as a method for investigating unconceptualised groups. Following this, through reference to my own research, I argue that the foundations of this methodology can be developed to include the broad networks of influences extant in contemporary cultures. To this end, I consider a solution that poses the researcher as a locus of investigation from which the relationships that construct a culture may be collated and interpretations built. Findings - The research account I have presented tackles this issue, synthesising introspection, thick inscription, and thick transcription, and moving the researcher through a multi-vocal, iterative, non-linear process. Historical, technological and ideological influences come into play to negotiate between possible realities. Ethnography may place these realities into their broader political, social and personal contexts and continue yielding data for the theorisation of contemporary cultures. Originality/value - The paper reassesses the experience of global culture with reference to the global surfing scene. It provides a practical solution to research in such cultures, and highlights the importance of a networked approach in the construction of adequate theory. [ABSTRACT FROM AUTHOR]

Presents the author index for the December 2004 issue of the periodical "Addiction."

Childhood traumatic grief (CTG) is a condition in which trauma symptoms impinge on children's ability to negotiate the normal grieving process. Clinical characteristics of CTG and their implications for treatment are discussed, and data from a small number of open-treatment studies of traumatically bereaved children are reviewed. An empirically derived treatment model for CTG is described; this model addresses both trauma and grief symptoms and includes a parental treatment component. Future research directions are also addressed. [ABSTRACT FROM AUTHOR]

The amount of community violence that children and adolescents are exposed to is unsettling. Intensifying the issue, the amount of community violence that is witnessed or experienced directly by children and adolescents is increasing with time. It has been documented that children and adolescents who are exposed to community violence display a wide array of psychological symptoms, ranging from depress/or and anxiety to antisocial and suicidal behaviors. Many variables have been studied in an attempt to determine correlates, moderators, and mediators of exposure to community violence. Furthermore, many intervention strategies have been developed from the discovery of relations/tips among these variables. Despite these efforts, many children continue to suffer from the negative effects of exposure to community violence. The purpose of this article is to encourage mental health professionals to mobilize their efforts to help children, adolescents, and their families cope with the effects of community violence. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Zoology is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Children may develop a variety of difficulties following victimization, including posttraumatic stress disorder (PTSD), other anxiety symptoms, depressive disorders, externalizing symptoms, or substance use disorders. Some children appear to be resilient in the face of victimization and do not report significant difficulties. A growing number of treatment studies for child abuse victims has supported the efficacy of trauma-focused cognitive–behavioral therapy (CBT); however, more research is needed to determine the critical components and optimal dosage of CBT, and to evaluate the efficacy of this approach for other groups of child crime victims. Psychopharmacological treatments are widely used for childhood PTSD, but little research has evaluated such treatments. Treatment guidelines and future directions are discussed. [ABSTRACT FROM AUTHOR]

A review of research on deaf students in higher education reveals a significant body of knowledge about the barriers these students face in gaining access to information in the classroom. Much less is known about the potential solutions to these problems. In addition, there is a dearth of research on the effectiveness of such support services as interpreting, note taking, real-time captioning, and tutoring, particularly with regard to their impact on academic achievement. This article summarizes relevant research and suggests directions for educational researchers interested in enhancing academic success and the retention of deaf students in higher education programs. [ABSTRACT FROM PUBLISHER]

Childhood traumatic grief refers to a condition in which characteristic trauma-related symptoms interfere with children is ability to adequately mourn the loss ofa loved one. Current concepts of this condition suggest that it overlaps with but is distinct from uncomplicated bereavement, adult complicated grief, and posttraumatic stress disorder. This article describes the core features of childhood traumatic grief; differentiates it from these related conditions; and reviews the current research status of suggested diagnostic criteria, assessment instruments, and treatments for this condition. Implications for future clinical practice, research, and policy are also addressed. [ABSTRACT FROM AUTHOR]

Abstract Harper (Parental Care in Mammals , Plenum Press, New York, 1981, p. 158) proposed that ‘there may be lower and upper limits for frequency or intensity of offspring stimulation that, on average, serve as reliable boundaries, below or above which it would be uneconomical to invest at all or at current levels.‘ This proposition was tested in captive common marmosets by comparing the responses of marmoset mothers exposed to differing number of infants. Fifteen common marmoset (Callithrix jacchus ) litters (seven twin and eight triplet litters) from 11 different dams were observed for 6–12, 30-min sessions over days 1–4 following birth. Mothers nursed smaller infants less frequently (F = 4.208, df = 1, 22; p = 0.052) regardless of litter size. The percent time mothers spent transporting (nursing and carrying) each infant was less for triplets than twins (F = 11.785, df = 1, 12; p = 0.005). Average transport bout length was significantly shorter for smaller infants (F = 7.566, df = 1, 22; p = 0.012) and was half as long for triplet infants as for twins (F = 10.733, df = 1, 7; p = 0.013). Twice as many transport bouts for triplets included maternal harassment of infants, than for twins (F = 42.742, df = 1, 24; p = 0.0001). Infant-initiated transfers to the mother were more common for triplets than for twins (Mann–Whitney U = 79.50, p = 0.006). The overall maternal carrying score (% carry × number of infants carried) was lower for triplet litters than for twin litters (F = 15.38, df = 1, 3; p = 0.029); i.e. mothers of triplets did not, overall, invest in more carrying and nursing than did mothers of twins but instead invested less. These findings suggest that, as opposed to the strong attraction to infants that is common for many primates, the marmoset mother's tolerance for carrying infants does not increase with increasing infant stimuli present; rather, marmoset mothers will only tolerate a limited amount of time... [ABSTRACT FROM AUTHOR]

This article discusses the importance of membership in the inclusive education of deaf/hard-of-hearing (D/HH) students. Membership refers to being an integral part of the classroom and school communities. Membership is a key philosophical concept in inclusion that may influence how classroom teachers and teachers of D/HH students share their expertise and how they work with students and each other. Membership can be contrasted with “visitorship.” When programs treat D/HH students as visitors, these students face greater barriers to obtaining a quality education in classes with hearing students. A social constructivist perspective of learning and teaching that requires students in the classroom to interact with one another and the teacher may best promote learning and is consistent with a focus on membership. We suggest that inclusion is possible, but to sustain students as full members of their classes and school, programs must go beyond placement and communication access issues. To facilitate membership, inclusive programs must carefully address teacher attitudes, teacher roles and relationships, student knowledge and curriculum, structural barriers, extracurricular activities, community relationships, and parental support. [ABSTRACT FROM PUBLISHER]

Focuses on U.S. laws that attempt to limit the work hours of medical residents. Economic realities of fiscal temperance; Effects of long hours on quality of patient care, residents' work conditions and quality of life; Voluntary professional organization limits.

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fifty deaf and hard-of-hearing students who were mainstreamed in postsecondary classes rated their classroom communication ease with hearing instructors, hearing peers, and deaf peers. A subgroup of these students participated in an in-depth interview that focused on perceptions of communication ease, support services, and attitudes of teachers and students toward deaf students in mainstreamed classes. Quantitative analyses indicated that students more comfortable in using speech in this setting reported being able to receive and send a greater amount and a higher quality of information than did students who were less comfortable in using speech. Both quantitative and quantitative results indicated that students varied considerably in their communication with hearing peers and professors, in their relations with deaf peers, and in their concerns about access. It is a challenge for interpreting and other support services to serve these various needs, especially when it is not unusual for these variations to occur in the same classroom. [ABSTRACT FROM PUBLISHER]

Details a study on the effects of renal medullary interstitial infusion of L-arginine on the development of high-salt-induced hypertension in Dahl salt-sensitive/Rapp (DS) rats. Methods; Results; Discussions.

In a separate paper, we developed a mathematical model describing HIV infection and used it to suggest experiments for quantifying characteristic viral parameters. In this paper we generalize the model to any well-mixed assay system. We also present complete and rigorous derivations of fundamental results needed for the design and analysis of HIV infectivity assays. The model is applicable to infectious agents with multiple receptors for their target cell (e.g. HIV, Epstein-Barr virus and Plasmodium), and to blockers (both reversible and irreversible), as long as blocker and target cells are the same diffusion compartment. [ABSTRACT FROM AUTHOR]

Discusses a study that focused on deaf and hearing children. Growth of social-cognitive knowledge in deaf and hearing children during the early and middle school years; Relative importance of language in 2 domains of social cognition; Implications of the results of the study on the role of language in social and personality development.

Wood frogs ( Rana sylvatica) were frozen to-2.5°C under five distinct cooling regimes to investigate the effect of cooling rate on survival. Frogs survived freezing when cooled at -0.16°C · h or -0.18°C · h, but mortality resulted at higher rates (-0.30°C · h,-1.03°C · h, and -1.17°C · h). Surviving frogs in the latter groups required longer periods to recover, and transient injury to the neuromuscular system was evident. Some of the frogs that died had patches of discolored, apparently necrotic skin; vascular damage, as indicated by hematoma, also occurred. It is concluded that slow cooling may be critical to the freeze tolerance of wood frogs. Additional studies examined the effect of cooling rate on physiological responses promoting freeze tolerance. Mean glucose concentrations measured in plasma (15-16 μmol · ml) and liver (42-45 μmol · g) following a 2-h thaw did not differ between slowly- and rapidly-cooled frogs but in both groups were elevated relative to unfrozen controls. Thus freezing injury to rapidly-cooled frogs apparently was not mitigated by the presence of elevated glucose. Water contents of liver tissue, measured 2 h post-thawing, did not differ between slowly-cooled (mean = 77.6%) and rapidly-cooled (mean = 78.5%) frogs. However, the mean hematocrit of slowly-cooled frogs (48%) was significantly higher than that (37%) of frogs cooled rapidly, possibly owing to differences in the dynamics of tissue water during freezing. [ABSTRACT FROM AUTHOR]

The relative activities of a series of nine monoalkyl esters of meso-2, 3-dimercaptosuccinic acid have been examined as agents for the mobilization of cadmium from mice one week after intraperitoneal administration of cadmium chloride. Eight of these are newly synthetized; all are of the type ROOCCH(SH)CH(SH)COOH, were R=Me, MMDMS; R = C2H5, MEDMS; R = (CH2)2CH3, Mn-PDMS; R = CHMe2) Mi-PDMS; R = (CH2)3CH3, M n-BDMS; R = CH2CHMe2, M i-BDMS; R = (CH2)4CH3, Mn-ADMS; R=(CH2)2CHMe2, Mi-ADMS; and R = (CH2)5CH3, M n-HDMS. All are soluble in dilute sodium bicarbonate solutions and can be administered as aqueous solutions. Cadmium mobilization data were collected on each compound using mice previously loaded with cadmium; the monoesters were administered at a level of 0.40 mmol/kg intraperitoneally daily for five days. Data on whole body cadmium mobilization indicated that the monoester with the isoamyl group was the most effective under the conditions used. The relative whole body cadmium mobilization increased with the number of carbon atoms in the alkyl group of the monoester up to C5 and then decreased for the C6 compound. Cadmium removal from the kidneys and liver was also measured. It was found that the monoisoamyl ester was the most effective in removing cadmium from both the liver and the kidneys. The monoisoamyl ester also proved to be very effective in mobilizing cadmium from both the liver and the kidneys when given orally. This is the first compound which is reported capable of mobilizing cadmium in vivo from aged deposits after oral administration. [ABSTRACT FROM AUTHOR]

Copyright of Archivos de Zootecnia is the property of Archivos de Zootecnia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: in diabetes, multiple mHealth solutions were produced and implemented for self-management behaviors. However, little research on the effectiveness of psychological techniques implemented within these mHealth solutions was carried out, and even less with the elderly population where technological barriers might exist. Reliable evidence generated through a comprehensive evaluation of mHealth interventions may accelerate its growth for successful long-term implementation and to help to experience mHealth benefits in an enhanced way in all ages. Objective: this study aimed to review mHealth solutions for diabetes self-management in older adults (adherence to treatments and glycemic control) by analyzing the effectiveness of specific psychological techniques implemented. Methods: a narrative review was conducted following preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. PubMed (Medline) and American Psychological Association (APA) PsycInfo databases were searched for published papers that addressed eHealth solutions' effectiveness for diabetes self-management. Studies in English, Spanish, and/or German of any design were screened, with no time constraints regarding the year of publication. A qualitative analysis of the selected papers was conducted in several steps. Results: this review found 38 studies setting up and analyzing mHealth solutions for older adults. Most research showed improvements in HbA1c, self-management behaviors, and medication adherence in T2DM patients post intervention. However, different mid-to-long term effects were found across studies, specifically concerning the maintenance and adherence to healthy behaviors. The most employed psychological framework was CBT, including techniques such as self-monitoring of outcome behaviors (mostly targeting glycemia measurements and healthy habits as physical activity and/or diet), tailored motivational feedback from medical staff, and psychoeducation or health coaches. The most successful mHealth intervention combined the feature of tailored feedback messages, interactive communication with healthcare professionals, and multifaceted functions. Conclusions: there is a lack of elaborate and detailed information in the literature regarding the factors considered in the design and development of mHealth solutions used as interventions for T2DM self-management in the elderly. Documentation and inclusion of such vital information will foster a transparent and shared decision-making process that will ultimately lead to the development of useful and user-friendly self-management apps that can enhance the quality of life for diabetes patients. Further research adapting mHealth solutions to older adults' sensory deficits is necessary. [ABSTRACT FROM AUTHOR]