“Rule 07” was proposed 2 years ago as a convenient rule of thumb to estimate the dark current density for state-of-the-art planar, ion-implanted,
p
/
n
HgCdTe photodiodes fabricated in layers grown ...by molecular-beam epitaxy (MBE). The best reported HgCdTe devices from other laboratories had dark currents no lower than the rule and often higher. In the intervening time we have continued to compare the rule with performance obtained by ourselves and others to see if it stands the test of time. We also examined why it succeeds in approximating the dark current density over the thermal infrared wavebands (>4.6
μ
m cutoff). It turns out that the rule has held up well, still predicting dark current density values within 0.4× to 2.5× over about 13 orders of magnitude. At least at mid-wavelength infrared–long-wavelength infrared wavelengths, where the dependence is exponential with inverse cutoff and temperature, the behavior can be explained by Auger 1 processes and the diode architecture. This has significant implications for high-operating-temperature devices.
“Rule 07,” a simple empirical relationship, conveniently estimates state- of-the-art HgCdTe dark current performance over 13 orders of magnitude, covering wavelength ranges form short-wave infrared ...(SWIR) to long-wave infrared (LWIR), from room temperature to liquid nitrogen temperatures. The best HgCdTe, in some cases, approaches the external radiative limit of performance, but is typically two to three orders of magnitude above that, being limited by defect generation centers as yet unidentified and/or by Auger mechanisms. The empirical relationship represents the range of detectors fabricated at Teledyne using our molecular beam epitaxy (MBE)-based double-layer planar heterostructure (DLPH) technology, but also appears to characterize good detectors from other laboratories.
Everyday walking often involves simultaneous performance of a cognitive task in environments with competing auditory and visual stimuli. Previous research has not evaluated task performance in these ...situations, where older adults are known to fall, limiting our understanding of how older adults adjust their gait, visual scanning (gaze), and cognitive processing to avoid falls (or not). The purpose of this study was to examine the effect of dual-task walking in a high-distraction real-world environment on cognitive performance, gait performance, and gaze behavior in older adult fallers relative to non-fallers.
Fourteen community-dwelling, older adult fallers (76.6 ± 9.1 years, 11 females) and 15 community-dwelling, older adult non-fallers (77.4 ± 7.6 years, 11 females) participated. Participants performed single-task walking, single-task cognitive (seated category naming), and dual-task walking (category naming + walking) trials for 1 min each in a real-world environment (busy hospital lobby). Gait speed, stride length variability, stride duration variability, gaze fixation duration on 6 areas of interest (AOIs), and percentage of time fixating on 6 AOIs were recorded during single- and dual-task walking trials. Number of correct responses, time to first response, and mean subsequent response time (measure of rate of decline of response retrieval throughout trial) were determined for single-task cognitive and dual-task walking trials. Two-way MANCOVAs and MANOVAs were used to compare the effects of fall status and task condition on gait and cognitive variables. Hierarchical linear regression models were used to assess predictors of gaze behavior variables.
Compared to single-task, during dual-task trials, participants walked 0.21 m/s slower, had 1.5 fewer verbal responses, and a 2823 ms shorter mean subsequent response time, indicating a faster declining rate of retrieval during the cognitive task. Additionally, during dual-task walking, participants fixated their gaze on Far People (AOI) for a significantly smaller percentage of time and on the Near Walking Path (AOI) for a significantly greater percentage of time than during single-task walking. During all trials, being a non-faller predicted a longer average fixation duration on the Far Environment (AOI) than for fallers. Environmental busyness, baseline gait speed, and baseline executive function impacted gaze behavior.
All participants exhibited dual-task decrements in gait and cognitive performance and changes in gaze behavior from single- to dual-task walking. Perhaps of more importance, non-fallers appear to have had more freedom to divert their gaze to less relevant environmental stimuli while walking, and two measures of fall risk impacted patterns of gaze behavior differently. Thus, overt visual attention during walking in real-world environments should be further explored in relation to fall risk.
•Dual-tasking impacts gait, gaze, and cognitive performance in older adults.•Fallers exhibit different gaze behavior than non-fallers in a real-world setting.•Overt visual attention while walking is impacted by different measures of fall risk.
Aim: Allen's rule posits that the appendages of endothermic organisms will be larger in warmer climates to allow for dumping of heat loads. Given a link between appendage size and climate, we tested ...the prediction that climate change has driven the evolution of larger bills in birds, resulting in measurable changes over the recent past. Location: Australia. Methods: We explored geographical and temporal variation in bill surface area of five Australian parrot species to determine whether individuals from warmer climates have larger bills, and whether there have been increases in bill surface area over time, consistent with climatic warming. Measurements were obtained from museum specimens dating from 1871 to 2008. These data were then related to geographical location, collection date and locality-specific climate data, in order to construct and compare models of spatio-temporal and climate-related variation in bill morphology. Results: There have been increases in bill surface area in mulga parrots (Psephotus varius), gang-gang cockatoos (Callocephalon fimbnatum), red-rumped parrots (Psephotus haematonotus) and male crimson rosellas (Platycercus elegans), equat ing to a c. 4–10% increase in bill surface area since 1871. Average maximum summer temperature in the 5 years prior to specimen collection also positively predicted bill surface area in mulga parrots, red-rumped parrots and crimson rosellas, consistent with Allen's rule. With the exception of red-rumped parrots, however, models with geographical location and year of collection were still better predictors of bill surface area than local climate at the date of collection. Main conclusions: Our analysis provides evidence that four species of parrot have exhibited adaptive change in bills over the past century potentially mitigating the thermal stress caused by climatic warming. Although consistent with the predicted effects of climate change, the temporal patterns we observe may have additional causes, however, such as changes in primary productivity, habitat or food availability.
The ability to decenter from internal experiences is important for mental health. Consequently, improving decentering is a common therapeutic target, particularly for mindfulness-based interventions. ...However, extant decentering measures are limited as they fail to directly assess all 3 metacognitive processes recently theorized to subserve decentering. We thus conducted 4 studies to develop and test the Metacognitive Processes of Decentering-Trait (MPoD-t) and State (MPoD-s) scales. Consistent with the metacognitive processes model, exploratory factor analysis (N = 355) and then bifactor exploratory structural equation modeling (N = 275) indicated the MPoD-t was composed of three independent yet interrelated lower-order factors, metaawareness, (dis)identification with internal experience, and (non)reactivity to internal experience, which subserved an emergent, higher-order, decentering factor. We next found evidence of the MPoD-t's convergent validity; as well as known-groups criterion validity, wherein mindfulness practitioners reported higher MPoD-t scores than nonpractitioners. Item response theory analyses were then used to identify a subset of 3 MPoD-t items for the MPoD-s. Finally, we found evidence that the MPoD-s was sensitive to changes in state decentering following a brief mindfulness induction relative to an active control condition; and that MPoD-s changes mediated the effect of mindfulness on levels of pain and related outcomes among a sample of preoperative surgery patients (N = 82). These studies indicate the trait and state versions of the MPoD may prove useful for the study of decentering and its constituent metacognitive processes. As such, the MPoD may help advance our understanding of how the metacognitive processes of decentering support mental health and well-being.
Public Significance Statement
This series of four studies developed trait and state versions of the Metacognitive Processes of Decentering Scale (MPoD). Results indicate the MPoD is a promising measurement tool with the potential to provide a more nuanced and refined understanding of decentering-an important factor for mental health and a valuable therapeutic mechanism.
Healthy Homes and Neighbourhoods (HHAN) Integrated Care Initiative was established to improve the care of families with complex health and social needs who reside in Sydney Local Health District. ...HHAN seeks to provide long-term multi-disciplinary care coordination as well as enhance capacity building and promote integrated care. The critical realist study reported here is part of the longitudinal development and evaluation of complex integrated health and social care interventions in Sydney, Australia.
We describe the qualitative component of a critical realist pilot case study aimed at exploring, explaining and refining emerging HHAN programme theories in relation to care coordination. Qualitative interviews were undertaken with HHAN clients (n = 12), staff and other stakeholders (n = 21). Interviews and coding used a context (C), mechanism (M) and outcome (O) framework. Inductive, deductive, retroductive and abductive modes of reasoning were used with the CMO heuristic tool to inform the developing programme theory.
The mechanisms underpinning effective engagement of clients by care coordinators included: building trust, leveraging other family, social and organisational relationships, meeting clients on their own terms, demonstrating staff effectiveness as quickly as possible, and client empowerment. Mechanisms for enhancing care integration included knowledge transfer activities and shared learning among collaborators, structural and cultural changes, enhancing mutual respect, co-location of multidisciplinary and/or interagency staff and cultivating faith in positive change among staff.
Use of a critical realism case study approach served to elucidate the varied influences of contexts and mechanisms on programme outcomes, to highlight what works for whom and in what context. Findings supported the initial programme theory that engagement and trust building with clients, alongside enhanced collaboration and integration of services, improved outcomes for vulnerable families with complex needs. Further research is needed to explore the cost-effectiveness of integrated care initiatives, in view of the long term nature of service provision and the risk of staff burnout.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Amyotrophic lateral sclerosis (ALS) is a late-onset neurological disorder characterized by death of motoneurons. Mutations in Cu/Zn superoxide dismutase-1 (SOD1) cause familial ALS but the mechanisms ...whereby they induce disease are not fully understood. Here, we use time-lapse microscopy to monitor for the first time the effect of mutant SOD1 on fast axonal transport (FAT) of bona fide cargoes in living neurons. We analyzed FAT of mitochondria that are a known target for damage by mutant SOD1 and also of membrane-bound organelles (MBOs) using EGFP-tagged amyloid precursor protein as a marker. We studied FAT in motor neurons derived from SOD1G93A transgenic mice that are a model of ALS and also in cortical neurons transfected with SOD1G93A and three further ALS-associated SOD1 mutants. We find that mutant SOD1 damages transport of both mitochondria and MBOs, and that the precise details of this damage are cargo-specific. Thus, mutant SOD1 reduces transport of MBOs in both anterograde and retrograde directions, whereas mitochondrial transport is selectively reduced in the anterograde direction. Analyses of the characteristics of mitochondrial FAT revealed that reduced anterograde movement involved defects in anterograde motor function. The selective inhibition of anterograde mitochondrial FAT enhanced their net retrograde movement to deplete mitochondria in axons. Mitochondria in mutant SOD1 expressing cells also displayed features of damage. Together, such changes to mitochondrial function and distribution are likely to compromise axonal function. These alterations represent some of the earliest pathological features so far reported in neurons of mutant SOD1 transgenic mice.
Background
The Canadian 24‐Hour Movement Guidelines for Children and Youth (“Guidelines”) not only pioneered the notion of an integrated movement continuum from sleep to vigorous‐intensity physical ...activity but also introduced a new branded Guideline visual identity.
Objectives
This study evaluated youths’ (N = 46) attention to and thoughts about the Guidelines and the brand.
Design
A cross‐sectional between‐participants randomized intervention design was used.
Sample
Canadian youth between 10 and 17 years of age comprised the study sample.
Interventions
Participants were randomly assigned to view either branded Guidelines (n = 26) or unbranded Guidelines (n = 20). Youths’ eye‐movements (e.g., dwell time, fixation count) were recorded during Guideline viewing. Participants completed a follow‐up survey assessing brand perceptions and Guideline cognitions.
Results
The branded Guidelines neither drew greater overall attention nor led to more positive brand perceptions or Guideline cognitions compared to the unbranded Guidelines.
Conclusions
Exploratory analyses provide valuable, yet preliminary insight into how branding and Guideline content may shape how Guidelines are perceived and acted upon. These findings inform an agenda for future health education resources.
Abstract The use of in silico predictions for the assessment of bacterial mutagenicity under the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use ...(ICH) M7 guideline is recommended when two complementary (quantitative) structure-activity relationship (Q)SAR models are used. Using two systems may increase the sensitivity and accuracy of predictions but also increases the need to review predictions, particularly in situations where results disagree. During the 4th ICH M7/QSAR Workshop held during the Joint Meeting of the 6th Asian Congress on Environmental Mutagens (ACEM) and the 48th Annual Meeting of the Japanese Environmental Mutagen Society (JEMS) 2019, speakers demonstrated their approaches to expert review using 20 compounds provided ahead of the workshop that were expected to yield ambiguous (Q)SAR results. Dr. Chris Barber presented a selection of the reviews carried out using Derek Nexus and Sarah Nexus provided by Lhasa Limited. On review of these compounds, common situations were recognised and are discussed in this paper along with standardised arguments that may be used for such scenarios in future.
The purpose of this study was to describe the social support networks and daily support interactions of cancer-affected individuals, including young adult (YA) and LGBTQIA+ survivors and care ...partners.
Participants were recruited at two United States cancer centers and
social media for a pilot study testing a novel online method for collecting prospective, daily social support interaction data (N=28). All participants were aged 18+; survivors had a current or recent cancer diagnosis and were engaged in treatment and/or services; care partners were identified by the survivors. Enrollment also purposefully targeted YA and LGBTQIA+ survivors. Social network data (up to 10 members) were assessed at baseline. Daily online surveys assessed support interactions between participants and specific network members over 14 days. Descriptive statistics summarized data and explored between-group (YA/non-YA, LGBTQIA+/non-LGBTQIA+) differences in social network characteristics (size, heterogeneity, density, centralization, cohesion) and support interactions (support source and type).
There were no significant differences between YA and non-YA participants on any measures. LGBTQIA+ participants' support networks were less dense (Mdn=0.69 vs. 0.82, p=.02), less cohesive (Mdn=0.85 vs. 0.91,.02), more centered on the participant (Mdn=0.40 vs. 0.24, p=.047), and included more LGBTQIA+ members (Mdn=0.35 vs. 0.00, p<.001). LGBTQIA+ participants reported having more interactions with LGBTQIA+ network members (Mdn=14.0 vs. Mdn=0.00, p<.001) and received significantly more of all types of support from LGBTQIA+ vs. non-LGBTQIA+ members. LGBTQIA+ participants also reported receiving more appraisal support than non-LGBTQIA+ (Mdn 21.64 vs. 9.12, p=.008) including more appraisal support from relatives (Mdn=11.73 vs 6.0, p+.037).
Important information related to support access, engagement, and needs is embedded within the everyday contexts of the social networks of cancer-affected people. Individualized, accessible, and prospective assessment could help illuminate how their "real world" support systems are working and identify specific strengths and unmet needs. These insights would inform the development of more culturally competent and tailored interventions to help people understand and leverage their unique support systems. This is particularly critical for groups like YA and LGBTQIA+ survivors and care partners that are underserved by formal support services and underrepresented in cancer, caregiving, and social support research.