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Attosecond transient absorption spectroscopy of highly excited states allows investigating the dynamics of both the decay and the light induced coupling between excited states. We present a rigorous quantum mechanical treatment that provides a generalized discussion of the on- and off-resonant decay dynamics, of resonant and non-resonant couplings to either discrete or continua states and the temporal evolution of the quantum beating of the excited wavepackets. The comparison of the model to experimental results obtained in xenon proves its general applicability.

Attosecond transient absorption spectra near the energies of autoionizing states are analyzed in terms of the photon coupling mechanisms to other states. In a recent experiment, the autoionization lifetimes of highly excited states of xenon were determined and compared to a simple expression based on a model of how quantum coherence determines the decay of a metastable state in the transient absorption spectrum. Here it is shown that this procedure for extracting lifetimes is more general and can be used in cases involving either resonant or nonresonant coupling of the attosecond-probed autoionizing state to either continua or discrete states by a time-delayed near infrared (NIR) pulse. The fits of theoretically simulated absorption signals for the 6p resonance in xenon (lifetime = 21.1 fs) to this expression yield the correct decay constant for all the coupling mechanisms considered, properly recovering the time signature of twice the autoionization lifetime due to the coherent nature of the transient absorption experiment. To distinguish between these two coupling cases, the characteristic dependencies of the transient absorption signals on both the photon energy and time delay are investigated. Additional oscillations versus delay-time in the measured spectrum are shown and quantum beat analysis is used to pinpoint the major photon-coupling mechanism induced by the NIR pulse in the current xenon experiment: the NIR pulse resonantly couples the attosecond-probed state, 6p, to an intermediate 8s (at 22.563 eV), and this 8s state is also coupled to a neighboring state (at 20.808 eV).

The broad bandwidth of an isolated attosecond pulse excites a vast number of states simultaneously, and the corresponding absorption features can be monitored with exceptional temporal resolution. Novel transient absorption experiments in gases using isolated attosecond pulses are performed in two regimes, one in which the attosecond pulse is overlapped in time with a near-infrared (NIR) pulse and one in which the NIR pulse follows the attosecond pulse. In the latter regime, the attosecond pulse first interacts with a sample, then the observed absorption features are modified by a NIR pulse, which interacts with the sample well after the attosecond pulse has passed. In these experiments, which seem counterintuitive when compared to conventional transient absorption spectroscopy, the weak attosecond pulse induces a polarization of the medium, which is then perturbed by the time-delayed NIR pulse. Recent measurements demonstrate the rich variety of information that can be extracted in this regime.

© 2014 Elsevier B.V. The broad bandwidth of an isolated attosecond pulse excites a vast number of states simultaneously, and the corresponding absorption features can be monitored with exceptional temporal resolution. Novel transient absorption experiments in gases using isolated attosecond pulses are performed in two regimes, one in which the attosecond pulse is overlapped in time with a near-infrared (NIR) pulse and one in which the NIR pulse follows the attosecond pulse. In the latter regime, the attosecond pulse first interacts with a sample, then the observed absorption features are modified by a NIR pulse, which interacts with the sample well after the attosecond pulse has passed. In these experiments, which seem counterintuitive when compared to conventional transient absorption spectroscopy, the weak attosecond pulse induces a polarization of the medium, which is then perturbed by the time-delayed NIR pulse. Recent measurements demonstrate the rich variety of information that can be extracted in this regime.

Electronic wavepackets composed of multiple bound excited states of atomic neon lying between 19.6 and 21.5 eV are launched using an isolated attosecond pulse. Individual quantum beats of the wavepacket are detected by perturbing the induced polarization of the medium with a time-delayed few-femtosecond near-infrared (NIR) pulse via coupling the individual states to multiple neighboring levels. All of the initially excited states are monitored simultaneously in the attosecond transient absorption spectrum, revealing Lorentzian to Fano lineshape spectral changes as well as quantum beats. The most prominent beating of the several that were observed was in the spin-orbit split 3d absorption features, which has a 40 femtosecond period that corresponds to the spin-orbit splitting of 0.1 eV. The few-level models and multilevel calculations confirm that the observed magnitude of oscillation depends strongly on the spectral bandwidth and tuning of the NIR pulse and on the location of possible coupling states.

The decay of highly excited states of xenon after absorption of extreme ultraviolet light is directly tracked via attosecond transient absorption spectroscopy using a time-delayed near-infrared perturbing pulse. The lifetimes of the autoionizing 5s5p66p and 5s5p67p channels are determined to be (21.9 ± 1.3) fs and (48.4 ± 5.0) fs, respectively. The observed values support lifetime estimates obtained by traditional linewidth measurements. The experiment additionally obtains the temporal evolution of the decay as a function of energy detuning from the resonance center, and a quantum mechanical formalism is introduced that correctly accounts for the observed energy dependence. © 2014 American Physical Society.

The development of attosecond technology is one of the most significant recent achievements in the field of ultrafast optics; it opens up new frontiers in atomic and molecular spectroscopy and dynamics. A unique attosecond pumpprobe apparatus using a compact Mach-Zehnder interferometer is developed. The interferometer system is compact (∼290 cm2) and completely located outside of the vacuum chamber. The location reduces the mechanical vibration from vacuum components such as turbopumps and roughing pumps. The stability of the interferometer is ∼50 as RMS over 24 hours, stabilized with an active feedback loop. The pump and probe fields can be easily altered to incorporate multiple colors. In the interferometer, double optical gating optics are arranged to generate isolated attosecond pulses with a supercontinuum spectrum. The frequencies of the attosecond pulses can be selected to be in the extreme ultraviolet (XUV) region (25–55 eV, 140 as) or the vacuum ultraviolet (VUV) region (15–24 eV, ∼400 as) by metal filters. Furthermore, the near infrared probe field (1.65 eV) can be upconverted to the ultraviolet (3.1 eV). The frequency tunability in the XUV and VUV is critical for selecting excited states of target atoms and molecules.

Recording the transmitted spectrum of a weak attosecond pulse through a medium, while a strong femtosecond pulse copropagates at variable delay, probes the strong-field dynamics of atoms, molecules, and solids. Usually, the interpretation of these measurements is based on the assumption of a thin medium. Here, the propagation through a macroscopic medium of helium atoms in the region of fully allowed resonances is investigated both theoretically and experimentally. The propagation has dramatic effects on the transient spectrum even at relatively low pressures (50 mbar) and short propagation lengths (1 mm). The absorption does not evolve monotonically with the product of propagation distance and pressure, but regions with characteristics of Lorentz line shapes and characteristics of Fano line shapes alternate. Criteria are deduced to estimate whether macroscopic effects can be neglected or not in a transient absorption experiment. Furthermore, the theory in the limit of single-atom response yields a general equation for Lorentz- and Fano-type line shapes at variable pulse delay. © 2013 American Physical Society.

Light-induced states in He atoms were characterized using attosecond transient absorption spectroscopy. A 400 as pulse covering the 20-24 eV spectral range serves as the probe pulse, and the effect of a few-cycle near infrared pulse (12 fs, 780 nm) on the absorption spectrum is measured as a function of time delay and near-infrared intensities varying from (5.0 ± 2) × 1010 to (1 ± 0.4) × 1013 W/cm2. Light-induced states resulting from near-infrared coupling of 1s2p to 1s2s, 1s3d, and 1s3s states are observed. Absorption features that likely result from coupling of 1s3p to 1s4s, 1s4d, 1s5s, and 1s5d states are also observed. The light-induced states with the smallest detunings (1s3d and 1s3s) from the dressing frequency may shift to higher frequencies as the dressing intensity is increased. © 2013, Taylor & Francis.

A school-based intervention designed to increase the positive nature of children's attitudes toward peers who use AAC is described. Small groups of children were given only information about AAC or they were given information about AAC and the opportunity to role-play being nonspeaking. Results indicated a greater positive effect of the information plus role-play experience compared to the effects of being given information alone for older children and boys. Clinical implications and suggestions for future research are discussed. [ABSTRACT FROM AUTHOR]

Background: Children with obesity may experience weight-based discrimination as a result of weight bias and stigma, which can have deleterious effects on their health and wellbeing, including increased risk of dysregulated, maladaptive, and disordered eating such as restriction, purging, and binging. Prior work has shown that weight bias occurs from healthcare workers caring for adults, but less is known about the prevalence of weight bias in the pediatric healthcare setting., Methods: We aimed to determine what proportion of pediatric healthcare professionals had attitudes of weight bias at our own institution by constructing a survey with questions from validated weight bias survey tools. Results revealed nearly half of all respondents had witnessed another healthcare professional make negative remarks about a patient with obesity, and many shared that they lacked the proper education/training and equipment to properly care for patients with obesity. Based on survey results, we created an electronic-based training module to educate healthcare professionals on weight bias and discrimination and how they may negatively affect care provided to children and families with obesity at our institution. Engagement with hospital leadership was a key strategy to ensure participation from medical and nursing/allied health staff in the survey, although only nursing/allied health leadership required the online training module resulting in limited physician engagement., Results: Feedback received regarding the training module was overwhelmingly positive., Conclusions: Our efforts illustrate that weight bias and discrimination exist in pediatric institutions, and that participation in a tailored electronic-based training module may be viewed as a helpful tool to raise awareness of how weight-based discrimination and bias can negatively affect patient care., (© 2024. The Author(s).)

Psychological stressors, like the nearby presence of a predator, can be strong enough to induce physiological/hormonal alterations, leading to appetite changes. However, little is known about how threats can alter feeding-related hypothalamic circuit functions. Here, we found that proenkephalin (Penk)-expressing lateral hypothalamic (LH Penk ) neurons of mice exposed to predator scent stimulus (PSS) show sensitized responses to high-fat diet (HFD) eating, whereas silencing of the same neurons normalizes PSS-induced HFD overconsumption associated with a negative emotional state. Downregulation of endogenous enkephalin peptides in the LH is crucial for inhibiting the neuronal and behavioral changes developed after PSS exposure. Furthermore, elevated corticosterone after PSS contributes to enhance the reactivity of glucocorticoid receptor (GR)-containing LH Penk neurons to HFD, whereas pharmacological inhibition of GR in the LH suppresses PSS-induced maladaptive behavioral responses. We have thus identified the LH Penk neurons as a critical component in the threat-induced neuronal adaptation that leads to emotional overconsumption., (© 2023. The Author(s).)

Cutaneous melanoma is the deadliest form of skin neoplasm and its high mortality rates could be averted by early accurate detection. While the detection of melanoma is currently reliant upon melanin visualisation, research into melanosome biogenesis, as a key driver of pathogenesis, has not yielded technology that can reliably distinguish between atypical benign, amelanotic and melanotic lesions. The endosomal-lysosomal system has important regulatory roles in cancer cell biology, including a specific functional role in melanosome biogenesis. Herein, the involvement of the endosomal-lysosomal system in melanoma was examined by pooled secondary analysis of existing gene expression datasets. A set of differentially expressed endosomal-lysosomal genes was identified in melanoma, which were interconnected by biological function. To illustrate the protein expression of the dysregulated genes, immunohistochemistry was performed on samples from patients with cutaneous melanoma to reveal candidate markers. This study demonstrated the dysregulation of Syntenin-1, Sortilin and Rab25 may provide a differentiating feature between cutaneous melanoma and squamous cell carcinoma, while IGF2R may indicate malignant propensity in these skin cancers., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Diagnosis and assessment of patients with prostate cancer is dependent on accurate interpretation and grading of histopathology. However, morphology does not necessarily reflect the complex biological changes occurring in prostate cancer disease progression, and current biomarkers have demonstrated limited clinical utility in patient assessment. This study aimed to develop biomarkers that accurately define prostate cancer biology by distinguishing specific pathological features that enable reliable interpretation of pathology for accurate Gleason grading of patients. Online gene expression databases were interrogated and a pathogenic pathway for prostate cancer was identified. The protein expression of key genes in the pathway, including adaptor protein containing a pleckstrin homology (PH) domain, phosphotyrosine-binding (PTB) domain, and leucine zipper motif 1 (Appl1), Sortilin and Syndecan-1, was examined by immunohistochemistry (IHC) in a pilot study of 29 patients with prostate cancer, using monoclonal antibodies designed against unique epitopes. Appl1, Sortilin, and Syndecan-1 expression was first assessed in a tissue microarray cohort of 112 patient samples, demonstrating that the monoclonal antibodies clearly illustrate gland morphologies. To determine the impact of a novel IHC-assisted interpretation (the utility of Appl1, Sortilin, and Syndecan-1 labelling as a panel) of Gleason grading, versus standard haematoxylin and eosin (H&E) Gleason grade assignment, a radical prostatectomy sample cohort comprising 114 patients was assessed. In comparison to H&E, the utility of the biomarker panel reduced subjectivity in interpretation of prostate cancer tissue morphology and improved the reliability of pathology assessment, resulting in Gleason grade redistribution for 41% of patient samples. Importantly, for equivocal IHC-assisted labelling and H&E staining results, the cancer morphology interpretation could be more accurately applied upon re-review of the H&E tissue sections. This study addresses a key issue in the field of prostate cancer pathology by presenting a novel combination of three biomarkers and has the potential to transform clinical pathology practice by standardising the interpretation of the tissue morphology., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Racism and childhood obesity are both pervasive factors adversely affecting the health and wellbeing of children and adolescents in the United States. The association between racism and obesity has been touched upon in the literature; yet most work has focused on a few dimensions of intersectionality of these two domains at one time. The renewed focus on structural racism as the primary contributor to distress of Black individuals in the United States has highlighted the urgency of identifying the contributions of racism to the childhood obesity epidemic. The current article is not a complete review of the literature, rather, it is meant to take a broad narrative review of the myriad ways in which racism contributes to the obesity epidemic in Black youth to serve as a call to action for more research, prevention, and intervention. The current article illustrates how a number of mechanisms for the etiology and maintenance of obesity are heavily influenced by racism and how addressing racism is critical for ameliorating the childhood obesity epidemic.

Purpose: To assess the feasibility and acceptability of yoga incorporated into a pediatric weight management program (promoting health in teens; PHIT Yoga) to racially diverse caregivers and youth and to compare this program with a cohort that received a program that did not include yoga (PHIT Kids). Methods: Thirty children with obesity were enrolled in a 12-week pediatric weight management intervention (PHIT Kids, n  = 17; PHIT Yoga, n  = 13). Weight, BMI z-score (BMIz), BMI percent of the 95th percentile, and health habits assessment were obtained from both cohorts pre- and post intervention. Acceptability was assessed in the yoga cohort. Results: Fifty-four percent of children in the PHIT Yoga cohort and 65% of children in the PHIT Kids cohort attended ≥75% of the intervention sessions. Survey results support that the PHIT Yoga was acceptable to both caregivers and children. Improvements in BMIz were observed in 50% of children in each cohort and both groups improved on five of seven health habits; cohorts overlapped on three habits (breakfast, screen time, and sugar-sweetened drinks). Conclusion: Findings support that yoga classes added to a pediatric weight management program are feasible and acceptable in racially diverse children with severe obesity and their caregivers.

Objectives: Although tick-borne diseases account for a large number of health care visits in the United States, clinical practices for tick bite and Lyme disease treatment and prevention are not well understood. The objective of this study was to better understand factors associated with clinical practices related to tick bites and Lyme disease., Methods: In 2013-2015, questions about tick-bite evaluation, Lyme disease diagnosis and treatment, appropriate use of Lyme disease testing, and tick-bite prevention were included in Porter Novelli's DocStyles survey, a nationally representative annual web-based survey of health care providers. We performed analyses of responses by provider license type and state-level incidence (high or low) of Lyme disease in 2019., Results: A total of 4517 providers were surveyed across the 3 study years. Overall, 80.9% of providers reported that they had evaluated at least 1 patient for a tick bite, 47.6% had diagnosed at least 1 patient with Lyme disease, and 61.9% had treated at least 1 patient for Lyme disease in the previous year. Providers from states with a high incidence of Lyme disease saw more patients for tick bites and Lyme disease than providers from states with a low incidence of Lyme disease. Few providers correctly chose Lyme disease testing as clinically useful in the hypothetical case of a patient from a state with a high incidence of Lyme disease with an arthritic knee (36.0%) or with new-onset atrioventricular block (39.5%), and respondents across all provider types incorrectly chose testing when not clinically indicated. Most providers (69.7%) reported routinely recommending tick-bite prevention methods to patients., Conclusions: Many providers evaluate patients for tick bites and treat patients for Lyme disease, but knowledge about appropriate testing is low. Providers may benefit from tailored education about appropriate Lyme disease diagnosis, testing, and effective tick-bite prevention.

Research on intimate partner violence (IPV) has largely focused on heterosexual relationships, but, in recent years, researchers have expanded their focus to include same-sex relationships. Using meta-analytic techniques, this study was conducted to examine the relative strength of various risk markers for men and women being perpetrators and victims of physical IPV in same-sex relationships. Articles were identified through research search engines and screened to identify articles fitting the inclusion criteria, a process that resulted in 24 studies and 114 effect sizes for the meta-analysis. The strongest risk marker among those with at least two effect sizes for both male and female perpetration was psychological abuse perpetration. The strongest risk marker among those with at least two effect sizes for IPV victimization was also perpetration of psychological abuse for males and psychological abuse victimization for females. Among same-sex-specific risk markers, internalized homophobia and fusion were the strongest predictors for being perpetrators of IPV for men and women, respectively. HIV status and internalized homophobia were the strongest risk markers for IPV victimization for men and women, respectively. Of 10 comparisons between men and women in risk markers for IPV perpetration and victimization, only 1 significant difference was found. The results suggest that although same-sex and heterosexual relationships may share a number of risk markers for IPV, there are risk markers for physical IPV unique to same-sex relationships. Further research and increased specificity in measurement are needed to better study and understand the influence of same-sex-specific risk markers for IPV.

Purpose: The purpose of this study is to explore the effects of a daily mindfulness practice and 2 types of journaling on participants' development of self-compassion., Method: This was a between-groups design. All participants in a graduate counseling course engaged in a short daily mindfulness practice at the beginning of every class. Participants were randomly assigned to a counseling journal or a gratitude journal group. Participants were to write in their journals 2 to 5 times a week for the duration of the class. Participants completed the Self-Compassion Scale (Neff, 2003) and a questionnaire created by the 1st author before any mindfulness sessions were held and again at the completion of the course., Results: Participants' level of self-compassion increased from pretest to posttest. The self-compassion scores of participants who kept counseling journals increased more than did those of participants who kept gratitude journals. Qualitative data indicated that participants believed that mindfulness was an important quality for clinicians to possess and that they were accepting of the daily mindfulness practice., Conclusions: Engaging in a 12-min daily mindfulness practice utilizing simple yoga postures, breath work, reflective writing, and journaling done at a separate time appears to be an effective technique for increasing students' levels of self-compassion. Maintaining a counseling journal as opposed to a gratitude journal appears to enhance the effect of the daily mindfulness practice on self-compassion.

Purpose: The purpose of the present study was to explore the effects of a mindfulness practice on participants' levels of self-compassion, perfectionism, attention, and perceived and biological stress., Method: This was a between-groups design. Experimental participants engaged in a short mindfulness practice weekly for one academic semester; control participants did not. All participants completed three self-report scales measuring perceived stress, self-compassion, and perfectionism before and after mindfulness sessions. In addition, electrophysiological measures were taken before and after to determine changes in biological markers of stress and attention. Experimental participants also kept reflective journals that were analyzed qualitatively., Results: Compared with control participants, by the end of the semester, experimental participants' perceived stress levels and potentially negative aspects of perfectionism decreased and biological markers of stress and self-compassion improved. Experimental participants' reflective writings indicated they perceived the sessions to be beneficial. Although the results are promising, no significant effect was found for attention., Conclusions: Engaging in a 20-min mindfulness practice using simple yoga posture and breath work across an academic semester appears to be effective in reducing students' perceived and biological stress levels and maladaptive aspects of perfectionism and in increasing their self-compassion. These are all factors that can improve students' overall well-being.

This article is the sixth in a series of the comorbidities of childhood obesity and reviews psychosocial aspects with a focus on weight-based victimization and discrimination stemming from weight bias and stigma. Outcomes from these bullying and discriminatory experiences are pervasive and impact youth across all settings, including school. Lastly, this article provides recommendations on how to reduce bias and stigma to better serve these students in the school environment., (© 2015 The Author(s).)

Background: The current study compares the effectiveness of a condensed 12-week version and a 24-week version of the same pediatric behavioral weight management program., Methods: Children (n=162) between the ages of 8 and 18 years (baseline BMIz=2.39; standard deviation=0.29) were randomized to either a 12- or 24-week version of the same behavioral weight management program. Child anthropometric data were recorded at baseline, 6 weeks, 12 weeks, 24 weeks, and 12 months. A two-level longitudinal model was used to examine within- and between-group differences in BMIz change over time., Results: A significant group-by-time interaction was found (β=-0.01; standard error, <0.01; p<0.01) with the 24-week group showing greater reductions in BMIz. Children in the 24-week group showed significant BMIz reductions over time (z=-5.18; p<0.01), but children in the 12-week group did not (z=-0.85; p=0.39)., Conclusions: Children in the 24-week program demonstrated greater reductions in BMIz than children in the 12-week group. Therefore, there may be additional benefit to sessions above and beyond the 8- to 12-week minimum suggested for pediatric weight management programs.

Objective: Rates of obesity are elevated among children with special needs (e.g., autism spectrum disorder, Down syndrome, or developmental disabilities). The objective of this study was to evaluate the effectiveness of a multidisciplinary tailored intervention to treat obesity among youth with special needs., Method: Seventy-six children aged 2 to 19 years participated in a multidisciplinary weight management clinic adapted for children with special needs. A description of the patients presenting for specialized clinical services is provided, and the impact of the intervention on child body mass index (BMI) and food variety was examined for a subset (n = 30) of children. Descriptive statistics of the patient population at baseline were calculated and a series of t tests, correlations, and analysis of variance models examined change in BMI z-scores (BMIz) and diet variety. Factors related to treatment outcomes were also explored., Results: BMIz decreased significantly by the 6-month follow-up (M = 2.43 to M = 2.36, p < .01). There were significant increases in the variety of fruits, vegetables, and grains that children ate (t(16) = 3.18, p < .01; t(16) = 2.63, p = .02; t(16) = 2.37, p = .03, respectively)., Conclusion: A multidisciplinary clinic-based intervention was effective in reducing BMIz over a 6-month period and increasing the variety of foods that children were eating. These results have implications for providing tailored weight management interventions for youth with obesity and special needs.

Isomerization between the cis and trans conformers of the S(1) state of acetylene is studied using a reduced dimension discrete variable representation (DVR) calculation. Existing DVR techniques are combined with a high accuracy potential energy surface and a kinetic energy operator derived from FG theory to yield an effective but simple Hamiltonian for treating large amplitude motions. The spectroscopic signatures of the S(1) isomerization are discussed, with emphasis on the vibrational aspects. The presence of a low barrier to isomerization causes distortion of the trans vibrational level structure and the appearance of nominally electronically forbidden à (1)A(2)←X̃ (1)Σ(g)(+) transitions to vibrational levels of the cis conformer. Both of these effects are modeled in agreement with experimental results, and the underlying mechanisms of tunneling and state mixing are elucidated by use of the calculated vibrational wavefunctions.

A compact and robust Mach-Zehnder type interferometer coupled with the double optical gating technique provides tunable isolated attosecond pulses and streak field detection with fields centered at either 750 nm or 400 nm. Isolated attosecond pulses produced at 45 eV (with measured pulse duration of 114 ± 4 as) and 20 eV (with measured pulse duration of 395 ± 6 as) are temporally characterized with a 750 nm wavelength streak field. In addition, an isolated 118 ± 10 as pulse at 45 eV is measured with a 400 nm wavelength streak field. The interferometer design used herein provides broad flexibility for attosecond streak experiments, allowing pump and probe pulses to be specified independently. This capability is important for studying selected electronic transitions in atoms and molecules.

Purpose: Study 1 developed the Assessment of Attitudes Toward Augmentative and Alternative Communication-2 (AATAAC-2) to assess adolescents' attitudes toward peers who use AAC. Study 2 used the AATAAC-2 to examine influences of familiarity with people with disabilities; type of AAC device; and various combinations of gender of rater, AAC user, and communication partner on adolescents' attitudes., Method: In Study 1, 194 adolescents viewed videotapes depicting adolescents using AAC, then completed AATAAC-2. Study 2 utilized 8 videotapes depicting 4 different gender combinations of AAC user and communication partner as experimental stimuli. Each gender combination was filmed twice: once with a static touch screen device, and once with a dynamic touch screen device. One-hundred thirty-six adolescents were randomly assigned to view 1 of the 8 videos. Participants then completed AATAAC-2., Results: Study 1 demonstrated that AATAAC-2 has adequate psychometric properties. Raters' responses in Study 2 indicated no main effect of device type; girls were more positive than boys; and familiarity with peers with disabilities was associated with more positive attitudes. No 2-way interactions were significant; 3-way interaction of level of familiarity, gender, and type of device used was significant., Conclusions: Familiarity and gender contribute to adolescents' attitudes; type of AAC device combined with these factors to influence attitudes.

A single subject ABAB design was used to determine the efficacy of aided language stimulation to teach the use of AAC techniques to adults with developmental disabilities. Sixteen participants were divided into two equal groups. In each group, half of the participants were able to communicate functionally using spoken language and half had complex communication needs and did not have functional, symbolic communication systems. Each group met twice weekly for 30 min per session. Researchers modeled the use of AAC and followed scripts during music-based interventions. Sessions focused on social greetings, choosing songs to play, learning words and movements for the songs, and discussing the songs. Participants were encouraged to interact with each other and to facilitate each other's communications. Results suggest that responsiveness and use of AAC increased for all participants with complex communication needs.

This study aimed at demonstrating that the caregiving role affected the lives of caregivers of children with cancer the child's degree of dependence regarding the performance of daily life activities (DLA), the degree of help offered by others and the degree to which some aspects of the caregiver's life were affected by caregiving activities. Interviews were held with fifty caregivers of children between the ages of three and ten in a children's hospital, a referral center for cancer and hematological disorders in Campinas, Sao Paulo. These caregiving activities seriously affect the lives of the caregivers and, therefore, an assessment of these aspects may help the nurse detect the problems and plan the healthcare needed by the caregivers of children with cancer.

The purpose of this study was to identify the frequency of nursing diagnoses "caregiver role strain" and "risk for caregiver role strain" in 50 caregivers of children with cancer in a specialized children's cancer hospital in Campinas, São Paulo. The data for this descriptive cross-sectional study was obtained from the patients' files and interviews held with the caregiver using a specially formulated protocol. "Caregiver role strain" was presented by 78% of the caregivers and 100% presented the risk for "caregiver role strain" with at least two defining characteristics and six risk factors. The conclusion was that caregivers of children with cancer present a high risk for caregiver role strain.

Two videotapes were created of a child communicating with a voice output augmentative and alternative communication (AAC) device. In one the child communicated using formal English only and in the other the child communicated using formal English and age appropriate informal terms. Children in grades 4 and 5 viewed either the formal English only or the formal and informal English videotape. After viewing the videotape, children completed a measure of self-reported attitudes toward children who use AAC. Results indicated effects for gender and for the gender by grade interaction. These results are discussed along with clinical implications.

In mammalian cells, cyclin E-CDK2 complexes are activated in the late G1 phase of the cell cycle and are believed to have an essential role in promoting S-phase entry. We have targeted the murine genes CCNE1 and CCNE2, encoding cyclins E1 and E2. Whereas single knockout mice were viable, double knockout embryos died around midgestation. Strikingly, however, these embryos showed no overt defects in cell proliferation. Instead, we observed developmental phenotypes consistent with placental dysfunction. Mutant placentas had an overall normal structure, but the nuclei of trophoblast giant cells, which normally undergo endoreplication and reach elevated ploidies, showed a marked reduction in DNA content. We derived trophoblast stem cells from double knockout E3.5 blastocysts. These cells retained the ability to differentiate into giant cells in vitro, but were unable to undergo multiple rounds of DNA synthesis, demonstrating that the lack of endoreplication was a cell-autonomous defect. Thus, during embryonic development, the needs for E-type cyclins can be overcome in mitotic cycles but not in endoreplicating cells.

TIA-1 and TIAR are related proteins that bind to an AU-rich element (ARE) in the 3' untranslated region of tumor necrosis factor alpha (TNF-alpha) transcripts. To determine the functional significance of this interaction, we used homologous recombination to produce mutant mice lacking TIA-1. Although lipopolysaccharide (LPS)-stimulated macrophages derived from wild-type and TIA-1(-/-) mice express similar amounts of TNF-alpha transcripts, macrophages lacking TIA-1 produce significantly more TNF-alpha protein than wild-type controls. The half-life of TNF-alpha transcripts is similar in wild-type and TIA-1(-/-) macrophages, indicating that TIA-1 does not regulate transcript stability. Rather, the absence of TIA-1 significantly increases the proportion of TNF-alpha transcripts that associate with polysomes, suggesting that TIA-1 normally functions as a translational silencer. TIA-1 does not appear to regulate the production of interleukin 1 beta, granulocyte-macrophage colony-stimulating factor or interferon gamma, indicating that its effects are, at least partially, transcript specific. Mice lacking TIA-1 are hypersensitive to the toxic effects of LPS, indicating that this translational control pathway may regulate the organismal response to microbial stress.

We report here the cloning and characterization of human and mouse cyclin E2, which define a new subfamily within the vertebrate E-type cyclins, while all previously identified family-members belong to the cyclin El subfamily. Cyclin E2/CKD2 and cyclin E/CDK2 complexes phosphorylate histone H1 in vitro with similar specific activities and both are inhibited by p27Kip1. Cyclin E2 mRNA levels in human cells oscillate throughout the cell cycle and peak at the G1/S boundary, in parallel with the cyclin E mRNA. In cells, cyclin E2 is complexed with CDK2, p27 and p21. Like cyclin E, cyclin E2 is an unstable protein in vivo and is stabilized by proteasome inhibitors. Cyclin E2-associated kinase activity rises in late G1 and peaks very close to cyclin E activity. In two malignantly transformed cell lines, cyclin E2 activity is sustained throughout S phase, while cyclin E activity has already declined and cyclin A activity is only beginning to rise. We speculate that cyclin E2 is not simply redundant with cyclin E, but may regulate distinct rate-limiting pathway(s) in G1-S control.

Primordial germ cells (PGCs) give rise to both eggs and sperm via complex maturational processes that require both cell migration and proliferation. However, little is known about the genes controlling gamete formation during the early stages of PGC development. Although several mutations are known to severely reduce the number of PGCs reaching and populating the genital ridges, the molecular identity of only two of these genes is known: the c-kit receptor protein tyrosine kinase and the c-kit ligand (the steel factor). Herein, we report that mutant mice lacking TIAR, an RNA recognition motif/ribonucleoprotein-type RNA-binding protein highly expressed in PGCs, fail to develop spermatogonia or oogonia. This developmental defect is a consequence of reduced survival of PGCs that migrate to the genital ridge around embryonic day 11.5 (E11.5). The numbers of PGCs populating the genital ridge in TIAR-deficient embryos are severely reduced compared to wild-type embryos by E11.5 and in the mutants PGCs are completely absent at E13.5. Furthermore, TIAR-deficient embryonic stem cells do not proliferate in the absence of exogenous leukemia inhibitory factor in an in vitro methylcellulose culture assay, supporting a role for TIAR in regulating cell proliferation. Because the development of PGCs relies on the action of several growth factors, these results are consistent with a role for TIAR in the expression of a survival factor or survival factor receptor that is essential for PGC development. TIAR-deficient mice thus provide a model system to study molecular mechanisms of PGC development and possibly the basis for some forms of idiopathic infertility.

The Crk-associated substrate p130(Cas) (Cas) and the recently described human enhancer of filamentation 1 (HEF1) are two proteins with similar structure (64% amino acid homology), which are thought to act as "docking" molecules in intracellular signaling cascades. Both proteins contain an N-terminal Src homology (SH), three domain and a cluster of SH2 binding motifs. Here we show that ligation of either beta1 integrin or B cell antigen receptor (BCR) on human tonsillar B cells and B cell lines promoted tyrosine phosphorylation of HEF1. In contrast, Cas tyrosine phosphorylation was observed in certain B cell lines but not in tonsillar B cells, indicating a more general role for HEF1 in B cell signaling. Interestingly, pretreatment of tonsillar B cells with cytochalasin B dramatically reduced both integrin- and BCR-induced HEF1 phosphorylation, suggesting that some component of the BCR-mediated signaling pathway is closely linked with a cytoskeletal reorganization. Both HEF1 and Cas were found to complex with the related adhesion focal tyrosine kinase (RAFTK), and when tyrosine phosphorylated, with the adapter molecule CrkL. In addition, the two molecules were detected in p53/56(Lyn) immunoprecipitates, and Lyn kinase was found to specifically bind the C-terminal proline-rich sequence of Cas in an in vitro binding assay. These associations implicate HEF1 and Cas as important components in a cytoskeleton-linked signaling pathway initiated by ligation of beta1 integrin or BCR on human B cells.

TIA-1 and TIAR are RNA binding proteins of the RNA recognition motif (RRM)/ribonucleoprotein (RNP) family that have been implicated as effectors of apoptotic cell death. We report the structures of murine TIA-1 and TIAR (mTIA-1 and mTIAR) deduced from cDNA cloning, the mRNA and protein tissue distribution of mTIA-1 and mTIAR, and the exon-intron structures of the mTIA-1 and mTIAR genes. Both mTIA-1 and mTIAR are comprised of three approximately 100 amino acid N-terminal RRM domains and a approximately 90 amino acid C-terminal auxiliary domain. This subfamily of RRM proteins is evolutionarily well conserved; mTIA-1 and mTIAR are 80% similar to each other, and 96 and 99% similar to hTIA-1 and hTIAR, respectively. The overall exon-intron structures of the mTIA-1 and mTIAR genes are also similar to each other, as well as to the human TIA-1 gene structure. While Northern blot analysis reveals that mTIA-1 and mTIAR mRNAs have a broad tissue distribution, mTIA-1 and mTIAR proteins are predominantly expressed in brain, testis and spleen. At least two isoforms of both mTIA-1 and mTIAR are generated by alternative splicing. Murine TIA-1 isoforms including or lacking the exon 5 encoded sequences are expressed at a ratio of approximately 1:1, whereas mTIAR isoforms including or lacking the 5'-end of exon 3 sequences are expressed in a approximately 1:6 ratio. Molecular characterization of murine TIA-1 and TIAR RNA binding proteins provides the basis for a genetic analysis of the functional roles of these proteins during mammalian development.

Most controlled studies of facilitated communication (FC) have not validated it. One task, however, on which positive effects of FC have been demonstrated without facilitator influence is the Peabody Picture Vocabulary Test-R (PPVT-R). The present study investigated if the use of FC could be validated for either a group of subjects with autism or a group with severe to profound cognitive impairments, on the PPVT-R when facilitators were effectively screened from all visual and auditory stimuli. Additionally, the effect of mode of input-auditory or visual-on subjects' performance was investigated. Results did not validate the use of FC for the administration of the PPVT-R nor did they show any notable advantage of one mode of input over another.

The morbidity rate from perforation demands that appendicitis be diagnosed promptly in children with abdominal pain. Although admitting and observing uncertain instances of appendicitis can refine the diagnostic accuracy, it is often claimed, but not proved, that this necessitates increasing the number of perforations. To assess the risk of perforation while observing uncertain instances of childhood appendicitis, we admitted 150 consecutive referrals during a period of one and one-half years. Immediate appendectomy was performed for 74 patients (49 percent) with convincing clinical signs and symptoms for appendicitis. The remaining 76 (51 percent) with unconvincing clinical signs and symptoms were observed as inpatients. One-third of the patients admitted for observation (26 of 76) underwent appendectomy after an average period of 12 hours. Two-thirds (50 of 76) of the patients got better and were discharged from the hospital without an appendectomy after an average admission of two days. Seven of the 100 appendices removed were normal. Three of the observed patients had perforations, one of whom may have perforated during observation, but that child went on to do well. The 50 patients who got well without appendectomy were similar to the patients with appendicitis, but significantly less likely to have peritoneal signs (8 versus 70 percent), tenderness in the right lower quadrant (48 versus 81 percent) and guarding (19 versus 75 percent). We conclude that admission and active observation in the hospital of children with possible, but unconvincing, signs and symptoms of appendicitis is a safe and effective way to determine which patients need an operation.

A case of sigmoid carcinoma in a 16-year-old boy is presented and the topic of colonic carcinoma in the young is reviewed. Although colon carcinoma in the younger patient is uncommon, its prognosis is distinctly worse than in the adult population, because the preponderance of mucinous adenocarcinoma in children and young adults represents a more virulent type of colonic malignancy and because the delay in diagnosis contributes to a more advanced stage of the disease at the time of presentation. When dealing with symptoms potentially referrable to this disease, a thorough diagnostic work-up should ensue.

The ability of aphasic subjects to process the sounds and meanings of ongoing speech was tested. Subjects, 10 aphasic and 20 control, heard test sentences which contained one member of phonemically similar word pairs in one of three semantic contexts: congruent, neutral, and noncongruent. Immediately after hearing a sentence, subjects were to indicate which member of the word pair had been in the sentence. All subject groups had similar overall patterns of response to the different semantic contexts. The division of aphasic subjects into groups of high and low comprehenders revealed response differences. High comprehending aphasic subjects, like control subjects, demonstrated interactive processing of the sounds and meaning of speech while low comprehending aphasic subjects did not.

Thymic cysts are a rare cause of cervical masses in children. The cysts usually appear between ages 6 and 7 years and present as a soft swelling in the anterior triangle of the neck. The cysts may be small and unilocular or large and multilocular; they produce few symptoms. The etiology is unclear but may be related to remnants of tissue left in the cervical region when the thymus gland descends from the neck to the mediastinum during embryologic development. Forty-three cases of cervical thymic cysts have been reported in patients under 20 years of age. Two additional cases are reported in boys 5 and 9 years of age.

Mucosal proctectomy with endorectal pull-through allows the removal of all colonic mucosa with preservation of continence. This operation was performed in 19 patients with familial polyposis coli and ulcerative colitis. A temporary loop ileostomy was used to defunctionalize the anastomosis. Intestinal continuity was restored in 17 of the 19 patients. Mean duration of follow-up was 29 months. All patients are continent, and the mean number of bowel movements per 24 hours is 6. Follow-up barium studies revealed a gradual dilatation of the terminal ileum within the rectal cuff which accounts for the decrease in the number of bowel movements. This operation eliminates the risk of carcinoma without compromising sphincter function.