Attentional Factors Underlying Binocular Vision Loss in Amblyopia

Amblyopia is a neurodevelopmental disorder of vision that results from abnormal visual experience during early development. In addition to significant vision loss in one eye, individuals with amblyopia experience binocular dysfunction, difficulty with visuomotor coordination and attentional deficits. A key component of the vision loss associated with amblyopia is strong, chronic suppression of the amblyopic eye. Clinically, suppression remains challenging to treat, and is a key obstacle to rehabilitating visual function in amblyopia. This thesis examines whether suppressed visual information from the amblyopic eye remains available for processing within the brain and whether higher-order attentional processing is affected in amblyopia. Emerging evidence suggests that attentional mechanisms may contribute to interocular suppression and vision loss in amblyopia. Across four experiments, the findings from this thesis provide several major insights about amblyopia. Visual information seen only by a suppressed amblyopic eye retains a presence within the brain that may subsequently be used for attentional processing. Attentional mechanisms in amblyopia were found to be intact to some extent and thus can be engaged. Orienting visual attention was effective for targets seen by a partially suppressed amblyopic eye and even for complex face cues. Selective attentional tracking by the amblyopic eye was intact in anisometropic amblyopia but was impaired for strabismic amblyopia. Additionally, the process of attentional disengagement and re-engagement may be impaired during amblyopic eye viewing. Overall, these results demonstrate that the amblyopic eye continues to influence visual perception despite being suppressed under normal viewing conditions. As a result, appropriate refractive correction of the amblyopic eye should be clinically prescribed to optimize image quality for binocular combination. Furthermore, amblyopia may affect how visual attention is allocated between the eyes, providing a therapeutic target to guide future rehabilitative efforts

Investigation of Hand Forces, Shoulder and Trunk Muscle Activation Patterns and EMG/force Ratios in Push and Pull Exertions

When designing work tasks, one goal should be to enable postures that maximize the force capabilities of the workers while minimizing the overall muscular demands; however, little is known regarding specific shoulder tissue loads during pushing and pulling. This study quantitatively evaluated the effects of direction (anterior-posterior pushing and pulling), handle height (100 cm and 150 cm), handle orientation (vertical and horizontal), included elbow angle (extended and flexed) as well as personal factors (gender, mass and stature) on hand force magnitudes, shoulder and L5/S1 joint moments, normalized mean muscle activation and electromyography (EMG)/force ratios during two-handed maximal push and pull exertions. Twelve female and twelve male volunteers performed maximal voluntary isometric contractions under 10 push and pull experimental conditions that emulated industrial tasks. Hand force magnitudes, kinematic data and bilateral EMG of seven superficial shoulder and trunk muscles were collected. Results showed that direction had the greatest influence on dependent measures. Push exertions produced the greatest forces while also reducing L5/S1 extensor moments, shoulder moments with the 150 cm height and overall muscular demands (p < 0.0001). The 100 cm handle height generated the greatest forces (p < 0.0001) and reduced muscular demands (p < 0.05), but were associated with greater sagittal plane moments (p < 0.05). Females generated, on average, 67% of male forces in addition to incurring greater muscular demands (p < 0.05). The flexed elbows condition in conjunction with pushing produced greater forces with reduced overall muscular demands (p < 0.0001). Furthermore, horizontal handle orientation caused greater resultant moments at all joints (p <. 0.05) The results have important ergonomics implications for evaluating, designing or modifying workstations, tasks or equipment towards improved task performance and the prevention of musculoskeletal injuries and associated health care costs

Optional elements and variant structures in the productions of bei2 to give dative constructions in Cantonese-speaking adults and three-year-old children

To express object transfer, Cantonese-speakers use a ditransitive ([V-R-T] or [V-T-R] where V=Verb, T=Theme, R=Recipient), or a more complex prepositional/serial-verb (P/SV) construction. Clausal elements in Cantonese datives can be optional (resulting in full versus non-full forms) or appear in variant orders (full non-canonical and full canonical). We report on usage of dative constructions with the word bei2 to give in 86 parents and 53 three-year-old children during conversations. The parents used more P/SV than ditransitive bei2-datives, and vice versa for the children. Both groups showed a similar usage pattern of optional elements and variant structures in their ditransitive and P/SV bei2-datives. The roles of multiple construction types, optional elements and variant structures in children's learning of bei2-dative constructions are described. Copyright © 2009 Cambridge University Press.published_or_final_versio

The Bereavement Guilt Scale:Development and preliminary validation

The rationale, development, and validation of the Bereavement Guilt Scale (BGS) are described in this article. The BGS was based on a theoretically developed, multidimensional conceptualization of guilt. Part 1 describes the generation of the item pool, derived from in-depth interviews, and review of the scientific literature. Part 2 details statistical analyses for further item selection (Sample 1, N = 273). Part 3 covers the psychometric properties of the emergent-BGS (Sample 2, N = 600, and Sample 3, N = 479). Confirmatory factor analysis indicated that a five-factor model fit the data best. Correlations of BGS scores with depression, anxiety, self-esteem, self-forgiveness, and mode of death were consistent with theoretical predictions, supporting the construct validity of the measure. The internal consistency and test-retest reliability were also supported. Thus, initial testing or examination suggests that the BGS is a valid tool to assess multiple components of bereavement guilt. Further psychometric testing across cultures is recommended

Stigma never dies: Mourning a spouse who died of AIDS in China

Stigma towards people with HIV (PHIV) can affect their family members. In this study of 68 HIV seronegative participants in China whose spouse died of AIDS, 35.3% reported prolonged grief. Stigma beliefs towards PHIV (i.e., belief that PHIV&#39;s death leaves the deceased, the family and society better off) predicted grief symptoms. Social campaigns to combat stigma and grief therapy to reconstruct the meaning of HIV-related death may be helpful to reduce suffering in HIV bereaved. (C) 2015 Elsevier Ireland Ltd. All rights reserved

Longitudinal Evaluation of Pediatric Residency Didactics Transition from Noon Conference to an Academic Half Day

BACKGROUND: In 2009, the UNM Pediatric Residency transitioned program didactics from noon conference to an academic half day. Immediate evaluation of resident and faculty satisfaction, resident attendance, board exam pass rate and In-Training-Exam (ITE) scores showed improvements with this change. OBJECTIVE: Investigate the longitudinal impact of the academic half day at UNM on resident and faculty satisfaction, resident attendance and clinical knowledge in the form of standardized exam results. METHODS: In this mixed-methods study, surveys regarding satisfaction were conducted of current pediatric residents (n=32) and faculty (n=32) at UNM. To assess clinical knowledge, quantitative measures such as senior resident ITE scores and pediatric board exam pass rate will be evaluated. Finally, focus groups were conducted with pediatric residents and faculty separately to evaluate concepts related to resident autonomy, competence and engagement with the academic half day. RESULTS: Preliminary review of survey data shows 88% and 63% overall satisfaction with the academic half day format from residents and faculty respectively, consistent with 2012 study results. Similar to prior, residents feel that the academic half day does not interfere with clinical education (97%) or patient care duties (83%). Pediatric Board exam pass rate from 2015-2017 is 65% which is similar to pass rates prior to the academic half day. Senior resident ITE scores and resident attendance rates are currently being compiled. Initial review of focus groups shows preference for academic half day in relation to decreasing interruptions to patient care and increase in resident autonomy in clinical areas. CONCLUSIONS: Preliminary data shows sustained overall satisfaction amongst residents and faculty. Board exam pass rates are unchanged, focus groups have identified further areas of intervention including increased resident engagement in didactics

Xist recruits the X chromosome to the nuclear lamina to enable chromosome-wide silencing

The Xist long noncoding RNA orchestrates X chromosome inactivation, a process that entails chromosome-wide silencing and remodeling of the three-dimensional (3D) structure of the X chromosome. Yet, it remains unclear whether these changes in nuclear structure are mediated by Xist and whether they are required for silencing. Here, we show that Xist directly interacts with the Lamin B receptor, an integral component of the nuclear lamina, and that this interaction is required for Xist-mediated silencing by recruiting the inactive X to the nuclear lamina and by doing so enables Xist to spread to actively transcribed genes across the X. Our results demonstrate that lamina recruitment changes the 3D structure of DNA, enabling Xist and its silencing proteins to spread across the X to silence transcription

Complicated grief and posttraumatic stress symptom profiles in bereaved earthquake survivors:A latent class analysis

Background: Studies on mental health following disasters have primarily focused on posttraumatic stress disorder (PTSD), yet severe, enduring and disabling grief (i.e., complicated grief, CG) also appears relevant. Objective: The present study examines symptom profiles of PTSD and CG among bereaved Sichuan earthquake survivors one year after the disaster. Methods: Self-report measures of demographic, disaster, and loss-related characteristics and symptoms of PTSD and CG were administered among 803 survivors (63% women, mean age = 46.7 years). Latent class analysis (LCA) was performed to identify subgroups of people with different PTSD and CG symptom profiles. Results: The LCA demonstrated that a five class solution yielded the best fit, consisting of a CG class with low PTSD and high CG (N = 208), a combined class with high PTSD and high CG (N = 205), a class with low PTSD and partial CG (N = 145), a class with partial PTSD and CG (N = 136), and a resilient class with low PTSD and CG (N = 108). Being a woman (vs. man), losing a child or spouse (vs. other), being injured (vs. non-injured), and/or having a missing family member (vs. non-missing) predicted membership of the CG class compared to other classes. Conclusions: CG appears a unique consequence of disasters involving many casualties. Disaster survivors should be screened for CG and provided with appropriate psychological treatment