1,446 research outputs found
Ion Sources, Operation and Development
This research was sponsored by the National Science Foundation Grant NSF PHY-931478
Integration of Consumer-Based Activity Monitors into Clinical Practice for Children with Type 1 Diabetes: A Feasibility Study
Current technology commonly utilized in diabetes care includes continuous glucose monitors (CGMs) and insulin pumps. One often overlooked critical component to the human glucose response is daily physical activity habits. Consumer-based activity monitors may be a valid way for clinics to collect physical activity data, but whether or not children with type 1 diabetes (T1D) would wear them or use the associated mobile application is unknown. Therefore, the purpose of this study was to test the feasibility of implementing a consumer-based accelerometer directly into ongoing care for adolescents managing T1D. Methods: Adolescents with T1D were invited to participate in this study and instructed to wear a mobile physical activity monitor while also completing a diet log for a minimum of 3 days. Clinical compliance was defined as the number of participants who were compliant with all measures while also having adequate glucose recordings using either a CGM, insulin pump, or on the diet log. Feasibility was defined as \u3e50% of the total sample reaching clinical compliance. Results: A total of 57 children and teenagers between the ages of 7 and 19 agreed to participate in this study and were included in the final analysis. Chi-square results indicated significant compliance for activity tracking (p \u3c 0.001), diet logs (p = 0.04), and overall clinical compliance (p = 0.04). Conclusion: More than half the children in this study were compliant for both activity monitoring and diet logs. This indicates that it is feasible for children with T1D to wear a consumer-based activity monitor while also recording their diet for a minimum of three days
Qualitative and quantitative analysis of stability and instability dynamics of positive lattice solitons
We present a unified approach for qualitative and quantitative analysis of
stability and instability dynamics of positive bright solitons in
multi-dimensional focusing nonlinear media with a potential (lattice), which
can be periodic, periodic with defects, quasiperiodic, single waveguide, etc.
We show that when the soliton is unstable, the type of instability dynamic that
develops depends on which of two stability conditions is violated.
Specifically, violation of the slope condition leads to an amplitude
instability, whereas violation of the spectral condition leads to a drift
instability. We also present a quantitative approach that allows to predict the
stability and instability strength
The evolution of interdependence in a four-way mealybug symbiosis
Mealybugs are insects that maintain intracellular bacterial symbionts to supplement their nutrientpoor plant sap diets. Some mealybugs have a single betaproteobacterial endosymbiont, a Candidatus Tremblaya species (hereafter Tremblaya) that alone provides the insect with its required nutrients. Other mealybugs have two nutritional endosymbionts that together provide these nutrients, where Tremblaya has gained a gammaproteobacterial partner that resides in the cytoplasm of Tremblaya. Previous work had established that Pseudococcus longispinus mealybugs maintain not one but two species of gammaproteobacterial endosymbionts along with Tremblaya. Preliminary genomic analyses suggested that these two gammaproteobacterial endosymbionts have large genomes with features consistent with a relatively recent origin as insect endosymbionts, but the patterns of genomic complementarity between members of the symbiosis and their relative cellular locations were unknown. Here, using long-read sequencing and various types of microscopy, we show that the two gammaproteobacterial symbionts of P. longispinus are mixed together within Tremblaya cells, and that their genomes are somewhat reduced in size compared to their closest non-endosymbiotic relatives. Both gammaproteobacterial genomes contain thousands of pseudogenes, consistent with a relatively recent shift from a free-living to endosymbiotic lifestyle. Biosynthetic pathways of key metabolites are partitioned in complex interdependent patterns among the two gammaproteobacterial genomes, the Tremblaya genome, and horizontally acquired bacterial genes that are encoded on the mealybug nuclear genome. Although these two gammaproteobacterial endosymbionts have been acquired recently in evolutionary time, they have already evolved co-dependencies with each other, Tremblaya, and their insect host
Do small (6.6 Fr.) active and passive fixation defibrillation leads perform as well as larger sized leads? A multi-centre analysis
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Continuous Equilibrium in Affine and Information-Based Capital Asset Pricing Models
We consider a class of generalized capital asset pricing models in continuous
time with a finite number of agents and tradable securities. The securities may
not be sufficient to span all sources of uncertainty. If the agents have
exponential utility functions and the individual endowments are spanned by the
securities, an equilibrium exists and the agents' optimal trading strategies
are constant. Affine processes, and the theory of information-based asset
pricing are used to model the endogenous asset price dynamics and the terminal
payoff. The derived semi-explicit pricing formulae are applied to numerically
analyze the impact of the agents' risk aversion on the implied volatility of
simultaneously-traded European-style options.Comment: 24 pages, 4 figure
Association between Physical Activity and Sport Participation on Hemoglobin A1c among Children and Adolescents with Type 1 Diabetes
Purpose: To determine associations between physical activity (PA) and sport participation on HbA1c levels in children with type 1 diabetes (T1D). Method: Pediatric patients with T1D were invited to complete a PA and sport participation survey. Data were linked to their medical records for demographic characteristics, diabetes treatment and monitoring plans, and HbA1c levels. Results: Participants consisted of 71 females and 81 males, were 13 +- 3 years old with an average HbA1c level of 8.75 +- 1.81. Children accumulating 60 min of activity 3 days or more a week had significantly lower HbA1c compared to those who accumulated less than 3 days (p \u3c 0.01) of 60 min of activity. However, there was no significant difference in HbA1c values based on sport participation groups. A multiple linear regression model indicated that PA, race, age, duration of diagnosis, and CGM use all significantly predicted HbA1c (p \u3c 0.05). Conclusion: This study demonstrated the significant relationship between daily PA and HbA1c. Those in this sample presented with lower HbA1c values even if accumulating less than the recommended number of days of activity. Further, it was shown that sport participation alone may not be adequate enough to impact HbA1c in a similar manner
Changes in perceived stress and lifestyle behaviors in response to the COVID-19 pandemic in The Netherlands:An online longitudinal survey study
The COVID-19 pandemic has substantial implications for physical and mental wellbeing. This study investigated changes, over time, in lifestyle behaviors and perceived stress during the initial phase of the pandemic and associations with COVID-19 symptoms, in the Dutch general population. An online longitudinal survey study was performed with pre-lockdown measurements in February, and subsequently in April and June 2020 (n = 259, mean age 59 ± 14 years, 59% women). Self-report questionnaires were used to assess weight, diet quality, physical activity, alcohol intake, and smoking. Perceived stress was measured using the validated perceived stress scale (PSS-10). The presence of COVID-19 symptoms (yes/no) was defined as fever, or >3 of the following symptoms: weakness/tiredness, muscle ache, dry cough, loss of smell/taste, and breathing difficulties. Data were analyzed using linear mixed models, adjusted for age, sex, educational level, marital status and (change in) employment status. Minimal increases over time were observed in alcohol intake (0.6 ± 0.7 to 0.7 ± 1.1 glasses/day, p = 0.001) and smoking (9.5 ± 8.7 to 10.9 ± 9.4 cigarettes/day among 10% smokers, p = 0.03), but other lifestyle behaviors remained stable. In April 2020, 15% reported COVID-19-related symptoms, and in June 2020, this was 10%. The presence of COVID-19 symptoms was associated with increased perceived stress (p interaction = 0.003) and increased alcohol consumption (p interaction = 0.03) over time. In conclusion, in this prospective study, COVID-19 symptoms were associated with increases in perceived stress and alcohol consumption. Future research on biopsychosocial determinants and underlying mechanisms of lifestyle changes, as a response to the COVID-19 pandemic, is needed
Proporción diaria de alimento del diablillo antártico (pleuragramma antarcticum boulenger, 1902) en el este del mar de weddell
[EN] The daily ration of Pleuragramma antarcticum in the Eastern Weddell Sea was investigated from midwater and bottom trawl samples collected in the Antarctic in the summer of 1998. Using a gastric evacuation model that takes into account Weddell Sea temperature below zero and information on the prey type daily ration estimates were: 1.133% BW for immature fish of 10-16 cm and 0.484% BW for mature fish of 17-24 cm. The low daily ration intake was influenced by the low temperatures that limited the rate of gastric evacuation. This model seems more realistic than results from the classic Elliot & Persson and Eggers models that are also used in this paper, since their assumptions on feeding regularity are more rigid and they do not consider data of energy density of the prey[ES] La ración diaria de alimento de Pleuragramma antarcticum en el mar de Weddell es investigada en muestras de arrastres de fondo y pelágicas recogidas durante diferentes horas del dÃa en el verano antártico de 1998. Utilizando un modelo de evacuación gástrica que tiene en cuenta la temperatura bajo del Mar de Weddell e información sobre el tipo de presa, las estimaciones de consumo diario fueron: 1.133% BW para peces inmaduros entre 10 -16 cm y 0.484% BW para peces maduros entre 17-24 cm. La baja ración diaria ingerida estuvo influida por las bajas temperaturas que limitan la tasa de evacuación gástrica. Este modelo parece más realista que los resultados de los modelos clásicos de Elliot & Persson and Eggers también empleados, ya que sus asunciones sobre su periodicidad de alimentación son más rÃgidas y no consideran datos de densidad energética de las presasThis work was conducted under the SCAR EASIZ programme, and was supported by the Alfred Wegener Institute and the Spanish Antarctic ProgrammePeer reviewe
Effect of Flow on Caloric Curve for Finite Nuclei
In a finite temperature Thomas-Fermi theory, we construct caloric curves for
finite nuclei enclosed in a freeze-out volume few times the normal nuclear
volume, with and without inclusion of flow. Without flow, the caloric curve
indicates a smooth liquid-gas phase transition whereas with flow, the
transition may be very sharp. We discuss these results in the context of two
recent experiments, one for heavy symmetric system (Au + Au at 600A MeV) and
the other for highly asymmetric system (Au + C at 1A GeV) where different
behaviours in the caloric curves are seen.Comment: 11 pages revtex; 4 figs; version to appear in Phys. Rev. Let
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