TSIS Experiences with ISS Jitter from Inception to On-Orbit Operation

The TSIS instrument has been measuring solar irradiance on a continual basis since January 2018 as an external payload on the ISS. In 2014 when TSIS was directed to fly on the ISS, the jitter environment was highly uncertain, so TSIS designed a robust gimbaled pointing system that showed excellent disturbance attenuation throughout the design, test, and on-orbit phases of the program. This paper discusses how TSIS accounted for this uncertain jitter environment through-out the life of the program.TSIS was able to measure the ISS jitter during commissioning and determined that it was a relatively benign environment less than 4 arcseconds 1 at low frequencies (<0.5 Hz). More importantly, the measured pointing performance of TSIS was consistently found to be 4 arcseconds 1, which easily satisfied the jitter requirement of 60 arcseconds 1

Spatial patterns of tree yield explained by endogenous forces through a correspondence between the Ising model and ecology.

Spatial patterning of periodic dynamics is a dramatic and ubiquitous ecological phenomenon arising in systems ranging from diseases to plants to mammals. The degree to which spatial correlations in cyclic dynamics are the result of endogenous factors related to local dynamics vs. exogenous forcing has been one of the central questions in ecology for nearly a century. With the goal of obtaining a robust explanation for correlations over space and time in dynamics that would apply to many systems, we base our analysis on the Ising model of statistical physics, which provides a fundamental mechanism of spatial patterning. We show, using 5 y of data on over 6,500 trees in a pistachio orchard, that annual nut production, in different years, exhibits both large-scale synchrony and self-similar, power-law decaying correlations consistent with the Ising model near criticality. Our approach demonstrates the possibility that short-range interactions can lead to long-range correlations over space and time of cyclic dynamics even in the presence of large environmental variability. We propose that root grafting could be the common mechanism leading to positive short-range interactions that explains the ubiquity of masting, correlated seed production over space through time, by trees

Adjunctive technologies for intrapartum fetal monitoring: current perspectives and proof of concept for a novel approach

Fetal monitoring is a recurring theme in perinatal morbidity and mortality reports, highlighting the limitations of cardiotocography and current adjunctive technologies, such as fetal blood sampling (FBS). There is an unmet need for more robust methods of intrapartum fetal assessment. Microdialysis may help to detect babies at risk of hypoxia by monitoring trends in lactate and related metabolites from fetal scalp interstitial fluid in a minimally invasive manner. However, its clinical value remains unproven because there is limited evidence on the relationship between interstitial and arterial lactate. Translating advances in fetal monitoring technology into improved clinical outcomes also depends on how obstetricians use such technology in their practice, which few past studies have explored in depth. This research comprised two components. The first part aimed (1) to develop a neonatal piglet model of hyperlactataemia; and, using this model, (2) to investigate the relationship between interstitial and arterial lactate; and (3) to explore the feasibility of using subcutaneous microdialysis to monitor the metabolic response to hypoxia in vivo. Eight neonatal piglets were monitored under non-recovery general anaesthesia. Hyperlactataemia was achieved by means of alveolar hypoxia and/or intravenous sodium L-lactate infusion, with target lactate concentrations above 12 mmol/L. Microdialysate from two subcutaneous microdialysis catheters inserted into the scalp of each piglet was analysed for interstitial lactate, pyruvate, glucose and glutamate concentrations, which were compared to arterial blood gas measurements. A subset of dialysate samples underwent secondary analyses with the StatStrip Xpress® pointof- care lactate meter to assess its performance. In total, 432 dialysate samples were collected from seven piglets. There was variation in the piglets’ response to hypoxia therefore two piglets received lactate infusions, with four overall achieving target hyperlactataemia. Interstitial lactate, pyruvate and glucose concentrations were not affected by microdialysis catheter insertion. There was a strong positive correlation between arterial lactate and interstitial lactate, and weaker positive correlations with interstitial lactate-to-pyruvate and lactate-to-glucose ratios. Interstitial lactate mirrored trends in arterial lactate with an approximate time lag of 10 v to 20 min, although the closeness of agreement varied between piglets. StatStrip Xpress® lactate values showed a proportional negative bias relative to the reference microdialysis analyser, but trend data and assay precision were comparable. The second part of this research sought to understand how UK obstetricians use adjunctive fetal monitoring technologies and what factors influence their practice, as well as exploring attitudes towards new technology and other areas for improving practice. Data were collected through semi-structured telephone interviews with 16 obstetricians of varying career grade from nine maternity units across the UK, prior to thematic analysis. Most obstetricians reported performing FBS but attitudes towards it varied. The use of fetal monitoring technology was influenced by obstetricians’ individual clinical autonomy, the socio-cultural norms of their unit, and wider external factors, such as guidelines. Obstetricians recognised the limitations of current methods of monitoring, but enthusiasm towards new technology was checked by a scepticism of ‘computerisation’ and perceived barriers to changing practice; hence, better staff training was seen as the immediate priority for improving outcomes. In summary, the work presented in this thesis provides new insight into the current role of adjunctive technologies in UK obstetric practice and demonstrates proof of concept for subcutaneous microdialysis as a novel approach to monitoring metabolic wellbeing in the fetus and neonate. Although interstitial lactate reflected trends in arterial lactate in response to hypoxia and lactate infusion in neonatal piglets, further research is required to fully characterise this relationship, including standardisation of the hyperlactataemia model described here. This research has also identified a range of individual and contextual factors that influence how obstetricians use fetal monitoring technology and highlights the urgent need for future qualitative studies to improve understanding of this complex process, alongside efforts to develop new technology

Novel Bayesian Networks for Genomic Prediction of Developmental Traits in Biomass Sorghum.

The ability to connect genetic information between traits over time allow Bayesian networks to offer a powerful probabilistic framework to construct genomic prediction models. In this study, we phenotyped a diversity panel of 869 biomass sorghum (Sorghum bicolor (L.) Moench) lines, which had been genotyped with 100,435 SNP markers, for plant height (PH) with biweekly measurements from 30 to 120 days after planting (DAP) and for end-of-season dry biomass yield (DBY) in four environments. We evaluated five genomic prediction models: Bayesian network (BN), Pleiotropic Bayesian network (PBN), Dynamic Bayesian network (DBN), multi-trait GBLUP (MTr-GBLUP), and multi-time GBLUP (MTi-GBLUP) models. In fivefold cross-validation, prediction accuracies ranged from 0.46 (PBN) to 0.49 (MTr-GBLUP) for DBY and from 0.47 (DBN, DAP120) to 0.75 (MTi-GBLUP, DAP60) for PH. Forward-chaining cross-validation further improved prediction accuracies of the DBN, MTi-GBLUP and MTr-GBLUP models for PH (training slice: 30-45 DAP) by 36.4-52.4% relative to the BN and PBN models. Coincidence indices (target: biomass, secondary: PH) and a coincidence index based on lines (PH time series) showed that the ranking of lines by PH changed minimally after 45 DAP. These results suggest a two-level indirect selection method for PH at harvest (first-level target trait) and DBY (second-level target trait) could be conducted earlier in the season based on ranking of lines by PH at 45 DAP (secondary trait). With the advance of high-throughput phenotyping technologies, our proposed two-level indirect selection framework could be valuable for enhancing genetic gain per unit of time when selecting on developmental traits

Developmental Regulation of an Adhesin Gene during Cellular Morphogenesis in the Fungal Pathogen Candida albicans

Peer reviewedPublisher PD

The effect of adding ready-to-use supplementary food to a general food distribution on child nutritional status and morbidity : a cluster-randomized controlled trial

Background: Recently, operational organizations active in child nutrition in developing countries have suggested that blanket feeding strategies be adopted to enable the prevention of child wasting. A new range of nutritional supplements is now available, with claims that they can prevent wasting in populations at risk of periodic food shortages. Evidence is lacking as to the effectiveness of such preventive interventions. This study examined the effect of a ready-to-use supplementary food (RUSF) on the prevention of wasting in 6- to 36-mo-old children within the framework of a general food distribution program. Methods and Findings: We conducted a two-arm cluster-randomized controlled pragmatic intervention study in a sample of 1,038 children aged 6 to 36 mo in the city of Abeche, Chad. Both arms were included in a general food distribution program providing staple foods. The intervention group was given a daily 46 g of RUSF for 4 mo. Anthropometric measurements and morbidity were recorded monthly. Adding RUSF to a package of monthly household food rations for households containing a child assigned to the intervention group did not result in a reduction in cumulative incidence of wasting (incidence risk ratio: 0.86; 95% CI: 0.67, 1.11; p = 0.25). However, the intervention group had a modestly higher gain in height-for-age (+0.03 Z-score/mo; 95% CI: 0.01, 0.04; p < 0.001). In addition, children in the intervention group had a significantly higher hemoglobin concentration at the end of the study than children in the control group (+3.8 g/l; 95% CI: 0.6, 7.0; p = 0.02), thereby reducing the odds of anemia (odds ratio: 0.52; 95% CI: 0.34, 0.82; p = 0.004). Adding RUSF also resulted in a significantly lower risk of self-reported diarrhea (-29.3%; 95% CI: 20.5, 37.2; p < 0.001) and fever episodes (-22.5%; 95% CI: 14.0, 30.2; p < 0.001). Limitations of this study include that the projected sample size was not fully attained and that significantly fewer children from the control group were present at follow-up sessions. Conclusions: Providing RUSF as part of a general food distribution resulted in improvements in hemoglobin status and small improvements in linear growth, accompanied by an apparent reduction in morbidity