Fiber Optic Connectors Hachnochi, Daniel; Waite, Ben
NASA Tech Briefs,
05/2015, Volume:
39, Issue:
5
Magazine Article, Trade Publication Article
With the standardization of 4G wireless, the increase in cloud storage and computing, and the push for faster network data rates, the highest quality passive interconnect systems must be used. While ...the robustness and size of these interconnections, fiber types, and cable management all play major roles in the backbone, what happens at the tip of the connector also greatly affects the optical performance of the system. The industry is continually looking for ways to increase yield, decrease Cost of Consumables (CoC) and labor expense. Reducing the number of polishing steps helps. A new cleaving technique, using a CO2 laser, largely automates the process. The operator simply places the connector into the laser cleaver, the laser scans across the fiber and epoxy bead, and it cleaves both together. The human factor is eliminated from the cleaving and denubbing steps. Most 2.5 mm ferrules used by assembly manufacturers are preprocessed with an ROC of 15 to 25 mm. This ROC reduces the polishing time after traditional hand cleaving.
Saturn’s moon Enceladus has an ice-covered ocean; a plume of material erupts from cracks in the ice. The plume contains chemical signatures of water-rock interaction between the ocean and a rocky ...core. We used the Ion Neutral Mass Spectrometer onboard the Cassini spacecraft to detect molecular hydrogen in the plume. By using the instrument’s open-source mode, background processes of hydrogen production in the instrument were minimized and quantified, enabling the identification of a statistically significant signal of hydrogen native to Enceladus. We find that the most plausible source of this hydrogen is ongoing hydrothermal reactions of rock containing reduced minerals and organic materials. The relatively high hydrogen abundance in the plume signals thermodynamic disequilibrium that favors the formation of methane from CO₂ in Enceladus’ ocean.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
Io leaves a magnetic footprint on Jupiter's upper atmosphere that appears as a spot of ultraviolet emission that remains fixed underneath Io as Jupiter rotates. The specific physical mechanisms ...responsible for generating those emissions are not well understood, but in general the spot seems to arise because of an electromagnetic interaction between Jupiter's magnetic field and the plasma surrounding Io, driving currents of around 1 million amperes down through Jupiter's ionosphere. The other galilean satellites may also leave footprints, and the presence or absence of such footprints should illuminate the underlying physical mechanism by revealing the strengths of the currents linking the satellites to Jupiter. Here we report persistent, faint, far-ultraviolet emission from the jovian footprints of Ganymede and Europa. We also show that Io's magnetic footprint extends well beyond the immediate vicinity of Io's flux-tube interaction with Jupiter, and much farther than predicted theoretically; the emission persists for several hours downstream. We infer from these data that Ganymede and Europa have persistent interactions with Jupiter's magnetic field despite their thin atmospheres.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Despite concern that climate change could increase the human risk to malaria in certain areas, the temperature dependency of malaria transmission is poorly characterized. Here, we use a mechanistic ...model fitted to experimental data to describe how Plasmodium falciparum infection of the African malaria vector, Anopheles gambiae, is modulated by temperature, including its influences on parasite establishment, conversion efficiency through parasite developmental stages, parasite development rate, and overall vector competence. We use these data, together with estimates of the survival of infected blood-fed mosquitoes, to explore the theoretical influence of temperature on transmission in four locations in Kenya, considering recent conditions and future climate change. Results provide insights into factors limiting transmission in cooler environments and indicate that increases in malaria transmission due to climate warming in areas like the Kenyan Highlands, might be less than previously predicted.
Background
Long‐term neuropsychological deficits associated with pediatric cancers and the related treatments have been consistently reported. Whole brain cranial radiation therapy (CRT) is ...associated with neurocognitive impairment. As a result, physicians are reticent to use CRT in favor of systemic or intrathecal chemotherapy, which have a less clear impact on cognition.
Procedure
The current meta‐analysis examined post‐treatment neuropsychological performance of children diagnosed with cancer and treated with chemotherapy to better understand the impact of chemotherapy upon cognition. Relevant test scores from 18 empirical studies were utilized and analyzed in comparison to normative data yielding 199 unique effect sizes across nine neurocognitive domains.
Results
Children diagnosed with cancer, who received chemotherapy, demonstrated deficits in attentional capacity (g = −0.277). These deficits are noted in the context of relatively unaffected performance in other domains. When examining potential moderators, those tested more than 5 years after completion of treatment demonstrated better attentional performance than those tested within 5 years of treatment completion.
Conclusions
These deficits in attentional capacity have implications related to the academic success of these children. Given the potential for remediation strategies within this domain, neuropsychological assessment can be an integral aspect of long‐term care plans of survivors of childhood cancer.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In winter 2013/14 there was widespread flooding in England. Previous studies have described an increased prevalence of psychological morbidity six months after flooding. Disruption to essential ...services may increase morbidity however there have been no studies examining whether those experiencing disruption but not directly flooded are affected. The National Study of Flooding and Health was established in order to investigate the longer-term impact of flooding and related disruptions on mental health and wellbeing.
In year one we conducted a cross sectional analysis of people living in neighbourhoods affected by flooding between 1 December 2013 and 31 March 2014. 8761 households were invited to participate. Participants were categorised according to exposure as flooded, disrupted by flooding or unaffected. We used validated instruments to screen for probable psychological morbidity, the Patient Health Questionnaire (PHQ 2), Generalised Anxiety Disorder scale (GAD-2) and Post Traumatic Stress Disorder (PTSD) checklist (PCL-6). We calculated prevalence and odds ratios for each outcome by exposure group relative to unaffected participants, adjusting for confounders.
2126 people (23%) responded. The prevalence of psychological morbidity was elevated amongst flooded participants (n = 622 depression 20.1%, anxiety 28.3%, PTSD 36.2%) and disrupted participants (n = 1099 depression 9.6%, anxiety 10.7% PTSD 15.2%). Flooding was associated with higher odds of all outcomes (adjusted odds ratios (aORs), 95% CIs for depression 5.91 (3.91-10.99), anxiety 6.50 (3.77-11.24), PTSD 7.19 (4.33-11.93)). Flooded participants who reported domestic utilities disruption had higher odds of all outcomes than other flooded participants, (aORs, depression 6.19 (3.30-11.59), anxiety 6.64 (3.84-11.48), PTSD 7.27 (4.39-12.03) aORs without such disruption, depression, 3.14 (1.17-8.39), anxiety 3.45 (1.45-8.22), PTSD 2.90 (1.25-6.73)). Increased floodwater depth was significantly associated with higher odds of each outcome. Disruption without flooding was associated with borderline higher odds of anxiety (aOR 1.61 (0.94-2.77)) and higher odds of PTSD 2.06 (1.27-3.35)) compared with unaffected participants. Disruption to health/social care and work/education was also associated with higher odds of psychological morbidity.
This study provides an insight into the impact of flooding on mental health, suggesting that the impacts of flooding are large, prolonged and extend beyond just those whose homes are flooded.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Cassini mission to the Saturn system discovered a plume of ice grains and water vapor erupting from cracks on the icy surface of the satellite Enceladus. This moon has a global ocean in contact ...with a rocky core beneath its icy exterior, making it a promising location to search for evidence of extraterrestrial life in the solar system. The previous detection of molecular hydrogen (H2) in the plume indicates that there is free energy available for methanogenesis, the metabolic reaction of H2 with CO2 to form methane and water. Additional metabolic pathways could also provide sources of energy in Enceladus’ ocean, but they require the use of other oxidants that have not been detected in the plume. Here, we perform chemical modeling to determine how the production of radiolytic O2 and H2O2, and abiotic redox chemistry in the ocean and rocky core, contribute to chemical disequilibria that could support metabolic processes in Enceladus’ ocean. We consider three possible cases for ocean redox chemistry: Case I in which reductants are not present in appreciable amounts and O2 and H2O2 accumulate over time, and Cases II and III in which aqueous reductants or seafloor minerals, respectively, convert O2 and H2O2 in the ocean to SO42− and ferric oxyhydroxides. We calculate the upper limits on the concentrations of oxidants and on the chemical energy available for metabolic reactions in all three cases, neglecting any additional abiotic reactions which could further affect energy availability. For all three cases, we find that many aerobic and anaerobic metabolic reactions used by microbes on Earth could meet the minimum free energy threshold, ΔGmin, required for terrestrial life to convert ADP to ATP. We show that aerobic metabolisms could sustain up to ∼1 cell cm−3 within a 20 m depth across Enceladus’ seafloor, even in our second case where O2 and H2O2 are scarce. Additionally, anaerobic metabolisms could sustain up to ∼1 cell for every two cm−3 within this volume in our latter two cases. In contrast, methanogenesis could support up to 6×102 cells cm−3 throughout this depth, due to the potential for a high hydrogen production rate at the seafloor as indicated by H2 measurements from Enceladus’ plume. While methanogenesis is the only metabolism that predicts cell density values close to those reported in Earth’s oceans and Antarctic subglacial lakes at this depth, our reported values depend on the area considered to be inhabited, which could be smaller than the entire Enceladus seafloor. Overall, the capacity for aerobic and anaerobic metabolisms to meet or exceed ΔGmin as well as sustain positive cell density values indicate that oxidant production and oxidation chemistry could contribute to supporting possible life and a metabolically diverse microbial community on Enceladus.
•Exploration through geochemical modeling of potential metabolic processes in the ocean of Enceladus.•Evaluation of redox disequilibria in the Enceladus ocean.•Constraints on volatile redox species and biomass in the Enceladus ocean that will help direct future investigations.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Unpaid community volunteers are a vital public health resource in times of crisis. In response to the COVID-19 pandemic, community volunteers were mobilized to support mass vaccination efforts in ...many countries. To have this group's continued engagement, it is essential to understand the community volunteer experience, including the opportunities and challenges they encounter and how these contribute to their role satisfaction. This qualitative study investigated the factors contributing to community volunteers' role satisfaction at COVID-19 mass vaccination clinics in the Region of Waterloo, Canada.
Qualitative data were analyzed from 20 volunteers (aged 48-79 years) who had worked at one of four COVID-19 vaccination clinics in the Region of Waterloo, Canada. Data were analyzed thematically using an inductive coding process followed by an iterative process of grouping and identifying linkages and relationships within the themes.
Four interrelated themes were developed from the inductive analysis process. The theme of community volunteers feeling valued or disesteemed in their role depends on the interaction between the three themes of role description, role preparation, and clinic context.
For volunteers in crises such as the COVID-19 pandemic, volunteer role satisfaction depends on how their contributions are valued, the clarity of their role descriptions, volunteer-specific training, and the sentiments of volunteers and staff within the clinic context. Greater role satisfaction can help with retention as volunteers become more resilient and adaptable to the complex dynamic circumstances of a crisis response. Activities such as training and materials development for role preparations should be explicitly planned and well-resourced, even in crisis/pandemic situations. Building clinic managers' or supervisors' skills in communication during crisis/pandemic situations and the skills for the creation of team cohesion are critical investment areas.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The objective of this study is to examine associations between Hb levels and sarcopenia, low muscle strength, functional measures, and activities of daily living (ADL) and instrumental ADL (IADL) ...disabilities in older Australian men.
Men aged 70 years and older (2005-2007) from the Concord Health and Ageing in Men Project were assessed at baseline (n = 1,705), 2 years (n = 1,367), and 5 years (n = 958). The main outcome measurements were walking speed, muscle strength, ADL and IADL disabilities, and sarcopenia using the Foundation for the National Institutes of Health criteria (low appendicular lean mass adjusted for body mass index < 0.789 and poor grip strength < 26kg). Analysis was performed using Hb levels as a continuous measure, unadjusted and adjusted by age, income, body mass index, measures of health, estimated glomerular function, inflammatory markers, and medication use. Receiver operating characteristic curve analysis was performed to determine a threshold of Hb for each outcome.
In cross-sectional and longitudinal analysis, for every 1g/dL increase in Hb, there was a significant reduction in risk of sarcopenia, slow walking speed, poor grip strength, inability to perform chair stands, and ADL and IADL disabilities in unadjusted, age-adjusted, and multivariate-adjusted analysis. The highest value of the Youden Index for Hb was 14.2g/dL for sarcopenia and grip strength, 14.5g/dL for walking speed, and 14.4g/dL for all other outcomes.
Declines in Hb levels over time are associated with poor functional outcomes. The risks and benefits of interventions to increase Hb among older men warrant further investigation to differentiate whether this is an active contributor to age-related debility or a passive biomarker of it.
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