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We provide an assessment of the Infinity Two fusion pilot plant (FPP) baseline plasma physics design. Infinity Two is a four-field period, aspect ratio $A = 10$, quasi-isodynamic stellarator with improved confinement appealing to a max-$J$ approach, elevated plasma density and high magnetic fields ($ \langle B\rangle = 9$ T). Here $J$ denotes the second adiabatic invariant. At the envisioned operating point ($800$ MW deuterium-tritium (DT) fusion), the configuration has robust magnetic surfaces based on magnetohydrodynamic (MHD) equilibrium calculations and is stable to both local and global MHD instabilities. The configuration has excellent confinement properties with small neoclassical transport and low bootstrap current ($|I_{bootstrap}| \sim 2$ kA). Calculations of collisional alpha-particle confinement in a DT FPP scenario show small energy losses to the first wall (${\lt}1.5 \,\%$) and stable energetic particle/Alfvén eigenmodes at high ion density. Low turbulent transport is produced using a combination of density profile control consistent with pellet fueling and reduced stiffness to turbulent transport via three-dimensional shaping. Transport simulations with the T3D-GX-SFINCS code suite with self-consistent turbulent and neoclassical transport predict that the DT fusion power$P_{{fus}}=800$ MW operating point is attainable with high fusion gain ($Q=40$) at volume-averaged electron densities $n_e\approx 2 \times 10^{20}$ m$^{-3}$, below the Sudo density limit. Additional transport calculations show that an ignited ($Q=\infty$) solution is available at slightly higher density ($2.2 \times 10^{20}$ m$^{-3}$) with $P_{{fus}}=1.5$ GW. The magnetic configuration is defined by a magnetic coil set with sufficient room for an island divertor, shielding and blanket solutions with tritium breeding ratios (TBR) above unity. An optimistic estimate for the gas-cooled solid breeder designed helium-cooled pebble bed is TBR $\sim 1.3$. Infinity Two satisfies the physics requirements of a stellarator fusion pilot plant.
In this work, we present a detailed assessment of fusion-born alpha-particle confinement, their wall loads and stability of Alfvén eigenmodes driven by these energetic particles in the Infinity Two Fusion Pilot Plant baseline plasma design, a four-field-period quasi-isodynamic stellarator to operate in deuterium–tritium fusion conditions. Using the Monte Carlo codes, SIMPLE, ASCOT5 and KORC-T, we study the collisionless and collisional dynamics of guiding-centre and full-orbit alpha-particles in the core plasma. We find that core energy losses to the wall are less than 4 %. Our simulations shows that peak power loads on the wall of this configuration are approximately 2.5 MW m-$^2$ and are spatially localised, toroidally and poloidaly, in the vicinity of x-points of the magnetic island chain $n/m = 4/5$ outside the plasma volume. Also, an exploratory analysis using various simplified walls shows that shaping and distance of the wall from the plasma volume can help reduce peak power loads. Our stability assessment of Alfvén eigenmodes using the STELLGAP and FAR3d codes shows the absence of unstable modes driven by alpha-particles in Infinity Two due to the relatively low alpha-particle beta at the envisioned 800 MW operating scenario.
An analysis of the divertor designs for the Infinity Two fusion pilot plant (FPP) baseline plasma design is presented. The divertor uses an $m=5$, $n=4$ magnetic island chain, where m is the poloidal number and n is the toroidal number. Two divertor designs are presented. A classical divertor that is similar to the Wendelstein 7-X island divertor is analyzed using diffusive field-line following and the fluid code EMC3-Lite. For a baseline $800\text{ MW}$ operating point in Infinity Two, the conditions where the heat flux on the divertor plate remains in the acceptable region are analyzed. In addition a related, but different and novel large island backside divertor (LIBD) design is shown. The LIBD promises improved neutral pumping by closing the divertor through the use of baffling and with a structure inside the island, thus preventing neutralized plasma particles from reente ring the plasma.
The magnetohydrodynamic (MHD) equilibrium and stability properties of the Infinity Two fusion pilot plant baseline plasma physics design are presented. The configuration is a four-field period, aspect ratio $A = 10$ quasi-isodynamic stellarator optimised for excellent confinement at elevated density and high magnetic field $B = 9\,T$. Magnetic surfaces exist in the plasma core in vacuum and retain good equilibrium surface integrity from vacuum to an operational $\beta = 1.6 \,\%$, the ratio of the volume average of the plasma and magnetic pressures, corresponding to $800\ \textrm{MW}$ deuterium–tritium fusion operation. Neoclassical calculations show that a self-consistent bootstrap current of the order of ${\sim} 1\ \textrm{kA}$ slightly increases the rotational transform profile by less than 0.001. The configuration has a magnetic well across its entire radius. From vacuum to the operating point, the configuration exhibits good ballooning stability characteristics, exhibits good Mercier stability across most of its minor radius and it is stable against global low-n MHD instabilities up to $\beta = 3.2\,\%$.
There is increasing concern regarding efficacy of organ preservation protocol in laryngeal and hypopharyngeal cancers.
Method
This study retrospectively assessed disease-related and functional outcomes of 191 patients with non-metastatic laryngeal or hypopharyngeal squamous cell carcinoma treated with curative intent (radiotherapy with or without chemotherapy).
Results
Seventy-six patients (39.8 per cent) had a primary cancer in the larynx, and 115 patients (60.2 per cent) had a primary cancer in the hypopharynx. The median follow up was 39 months. The 3-year time to progression, overall survival, local control and laryngectomy free survival was 56.2 per cent, 76.3 per cent, 73.2 per cent and 67.2 per cent, respectively. At the time of analysis, 83 patients (43.5 per cent) were alive and disease free at their last follow up and did not require tube feeding or tracheostomy. The laryngo-oesophageal dysfunction-free survival was 61 per cent at 3 years.
Conclusion
Organ conservation protocols remain the standard of treatment in appropriately selected patients with laryngeal and hypopharyngeal cancers.
Mars exploration motivates the search for extraterrestrial life, the development of space technologies, and the design of human missions and habitations. Here, we seek new insights and pose unresolved questions relating to the natural history of Mars, habitability, robotic and human exploration, planetary protection, and the impacts on human society. Key observations and findings include:
– high escape rates of early Mars' atmosphere, including loss of water, impact present-day habitability;
– putative fossils on Mars will likely be ambiguous biomarkers for life;
– microbial contamination resulting from human habitation is unavoidable; and
– based on Mars' current planetary protection category, robotic payload(s) should characterize the local martian environment for any life-forms prior to human habitation.
Some of the outstanding questions are:
– which interpretation of the hemispheric dichotomy of the planet is correct;
– to what degree did deep-penetrating faults transport subsurface liquids to Mars' surface;
– in what abundance are carbonates formed by atmospheric processes;
– what properties of martian meteorites could be used to constrain their source locations;
– the origin(s) of organic macromolecules;
– was/is Mars inhabited;
– how can missions designed to uncover microbial activity in the subsurface eliminate potential false positives caused by microbial contaminants from Earth;
– how can we ensure that humans and microbes form a stable and benign biosphere; and
– should humans relate to putative extraterrestrial life from a biocentric viewpoint (preservation of all biology), or anthropocentric viewpoint of expanding habitation of space?
Studies of Mars' evolution can shed light on the habitability of extrasolar planets. In addition, Mars exploration can drive future policy developments and confirm (or put into question) the feasibility and/or extent of human habitability of space.
To evaluate the impact of early intervention using combined swallow therapy, consisting of traditional swallow exercises and transcutaneous neuromuscular electrical stimulation, on patients with advanced oropharyngeal squamous cell carcinoma.
Methods
A cohort study of 60 prospectively enrolled patients was performed. Thirty patients with advanced oropharyngeal squamous cell carcinoma starting combined swallow therapy two weeks after surgery that continued throughout chemoradiotherapy were compared with a matched cohort of 30 patients starting combined swallow therapy after cancer treatment completion. Gastrostomy tube status, modified barium swallow, and Functional Oral Intake Scale scores were assessed before and after therapy.
Results
Both cohorts demonstrated a statistically significant improvement in Functional Oral Intake Scale scores. All patients in the early intervention cohort discontinued gastrostomy tube use, compared with one-third in the control cohort, with greater improvements in Functional Oral Intake Scale scores. The tongue base was the site of greatest improvement in the early intervention group.
Conclusion
Early initiation of combined swallow therapy may optimise swallow outcomes in patients with advanced oropharyngeal squamous cell carcinoma.
ABSTRACT IMPACT: The findings suggest that targeting parenting stress in combination with psychoeducation on nutrition and physical activity may have positive effects in improving healthy food choices such as reduction of fast food intake, which may in turn impact the health of toddlers and their families. OBJECTIVES/GOALS: Parent stress is associated with a myriad of unhealthy behaviors including overeating, decreased physical activity, which contribute to increased weight. Several programs have aimed to increase education of nutrition, but few have focused on parent stress to improve healthy food intake. The present study assessed parent stress and fast food intake. METHODS/STUDY POPULATION: Parents who have obesity and had a toddler in the age group of 2-5 years were enrolled for a preventive intervention study to assess the effect of a parent-based intervention to improve family health choices and reduce childhood obesity risk. The sample included 105 participants, mean age 34.80 (6.27) years old, mean body mass index (BMI) 35.51 kg/m2, 39.0% Non-Hispanic White, 20.0% Non-Hispanic Black, 22.9% multiracial, 12.4% Hispanic, and 5.7% other. Stress was assessed using the Perceived Stress Scale (PSS) to assess overall general stress and the Parenting Stress Index (PSI) to assess parent-specific stress. Chaos in the home and fast food intake were also assessed using self-report surveys. RESULTS/ANTICIPATED RESULTS: Preliminary results are based on available data as of October 2020, data collection and recruitment are still in progress. There was a significant correlation between fast food intake with PSS (r=.18, p=.04), chaos (r=.24, p=.02), and PSI (r=.25, p=.01). Using a hierarchical regression model, we entered home chaos in the first block which explained a significant amount of the variability (R2= .06, p=.04). PSS was entered in the second block, which was not significant (R2 change=.01, p=.50), and in the final block PSI was entered and was significant (R2 change=.13, p <.01). DISCUSSION/SIGNIFICANCE OF FINDINGS: The data indicate that parenting stress uniquely predicts fast food intake above and beyond what could be explained by home chaos and general perceived stress. Future analyses will assess a parent-based intervention targeting stress reduction to improve weight and health for the parent and their toddlers in order to reduce childhood obesity risk.
We show that the Weibel or current filamentation instability can lead to the emission of circularly polarized radiation. Using particle-in-cell simulations and a radiation post-processing numerical algorithm, we demonstrate that the level of circular polarization increases with the initial plasma magnetization, saturating at ${\sim }13\,\%$ when the magnetization, given by the ratio of magnetic energy density to the electron kinetic energy density, is larger than 0.05. Furthermore, we show that this effect requires an ion–electron mass ratio greater than unity. These findings, which could also be tested in currently available laboratory conditions, show that the recent observation of circular polarization in gamma-ray burst afterglows could be attributed to the presence of magnetized current filaments driven by the Weibel or current filamentation instability.
A cross-sectional study on six dairy farms was conducted to ascertain the occurrence of carbapenem-resistant Escherichia coli in calves. Two-hundred and seventy-nine isolates of E. coli were recovered from 90 faecal samples from apparently healthy (45) and diarrhoeal (45) calves. The isolates were screened for phenotypic susceptibility to carbapenems and production of metallo β-lactamase, as well as five carbapenemase resistance genes by PCR, and overexpression of efflux pumps. Eighty-one isolates (29.03%) were resistant to at least one of three carbapenem antibiotics [meropenem (23.30%), imipenem (2.15%) and ertapenem (1.43%)], and one isolate was positive for the blaVIM gene which was located on an Incl1 plasmid of a novel sequence type (ST 297) by multilocus sequence typing. The majority (83.95%) of isolates had an active efflux pump. Calves housed on concrete floors were approximately seven times more likely to acquire meropenem-resistant isolates than those housed on earthen floors (95% CI 1.27–41.54). In India, carbapenem drugs are not used in food animal treatment, hence carbapenem-resistant strains in calves possibly originate from the natural environment or human contact and is of public health importance. To our knowledge, this is the first report of blaVIM carbapenemases gene in calves from India.
The rocks of the Jasra intrusive complex (Shillong Plateau, northeastern India) include phlogopite clinopyroxenites (with olivine or perovskite relics), alkali gabbros/monzodiorites, syenites and nepheline syenites. They have a potassic affinity (Na2O/K2O ∼1),and their mineralogy is dominated by clinopyroxene with which phlogopite, olivine, amphibole, feldspars, feldspathoids, oxides, orthopyroxenes, perovskite, titanite and other accessory phases are variably associated. The Jasra intrusive rocks are cumulates derived from at least two distinctmagmatic liquids. The potassic affinity of the Jasra rocks differs from the nearby Sung Valley ijolitic-carbonatitic complex and from the ultrapotassic lamproitic rocks of the Damodar Valley, which are of approximately the same age. This suggests major variability in the mantle sources ofsmall-volume alkaline volcanism in the Early Cretaceous of northeastern India.
This paper describes the growth of sea ice and the salinity profiles observed in Eclipse Sound near Pond Inlet, Baffin Island, Canada, during the winter of 1977–78. A numerical method of calculation has been developed to incorporate the variations in snow conditions and physical properties of ice and snow during the growth season. It is shown that the growth rate can be predicted reasonably well. It is also shown that the vertical salinity profile in the ice towards the end of the season, provides a record of previous climatological conditions. A dependence has been shown between the predicted growth rate and the measured salinity.
As Canada’s population ages, frailty – with its increased risk of functional decline, deterioration in health status, and death – will become increasingly common. The physiology of frailty reflects its multisystem, multi-organ origins. About a quarter of Canadians over age 65 are frail, increasing to over half in those older than 85. Our health care system is organized around single-organ systems, impairing our ability to effectively treat people having multiple disorders and functional limitations. To address frailty, we must recognize when it occurs, increase awareness of its significance, develop holistic models of care, and generate better evidence for its treatment. Recognizing how frailty impacts lifespan will allow for integration of care goals into treatment options. Different settings in the Canadian health care system will require different strategies and tools to assess frailty. Given the magnitude of challenges frailty poses for the health care system as currently organized, policy changes will be essential.
A systematic review of the literature was conducted to identify effective approaches to preventing and addressing abuse and neglect of older adults within health care settings in Canada. The review was conducted using databases searched from January 2000–April-May 2013. Additionally, expert panel members submitted article citations from personal archives. Two research associates (NRA) screened each title and abstract for inclusion. After inter-rater reliability was determined between the NRAs (Kappa score of 0.76), the records were divided, appraised, and data extracted independently. The review resulted in 62 studies that focused on identifying, assessing, and responding to abuse and neglect of older adults; education, prevention, and health promotion strategies; and organizational and system-level supports to prevent and respond to abuse and neglect. Abuse and neglect of older adults remains under-explored in terms of evidence-based studies; consequently, further research in all of the areas described in the results is needed.
Cassava germplasm collection is important for the preservation of genetic variability, allowing the development of improved cultivars with desirable traits such as drought and disease tolerance, better starch quality and yield. Therefore, the assessment of diversity in cassava germplasm maintained by farmers is important for maintaining biodiversity and crop improvement. Herein, we report genetic diversity relationships of 52 farmer-preferred cassava landraces from the eastern zone of Tanzania based on morphological descriptors and single nucleotide polymorphisms (SNPs). Cluster analysis was performed for both morphological traits (genetic distance 1.18–0.15) and SNPs (genetic distance 0.078–0.002). The analysis revealed that there were a total of 17,393 variant positions, and that several of the SNPs were distributed across all the chromosomes. The abundance of SNP varied remarkably among the 18 cassava chromosomes, with chromosome 2 having the highest number of SNPs (1335) and chromosome 18 having the lowest number of SNPs (734). The power of SNPs in distinguishing morphologically similar landraces was shown. Both analyses did not group landraces according to geographical locations, suggesting that farmers were moving cassava germplasm to different areas. Their diversity was mainly due to adaptation and preferential selection by farmers. This further implied that within a geographical location, the cultivars were more diverse and there was no misnaming of cassava cultivars by farmers. The collection revealed a wide range of genetic diversity, and represented a valuable resource for trait improvement, allowing the capture of farmer-preferred traits in future cassava breeding programmes.
Manual documentation has an inherent problem of improper communication, manipulation, and validity. An electronic medical record (EMR) is a computerized medical record created in an organization that delivers care, such as a hospital. EMRs tend to be a part of a local, stand-alone, health information system that allows for storage and retrieval.
Objectives
The objective of this study was to assess the perception of emergency care providers toward the implementation of an EMR System in the emergency department of a Level-1 Trauma Center.
Methods
A qualitative survey was conducted among consenting doctors and nurses in the emergency department of the All India Institute of Medical Sciences February to October 2010. Data were collected from a sample of 22—eight doctors and 14 nurses. The collection tool was a structured, closed-ended questionnaire of 12 questions based on usability, applicability, and security, of EMR. A Likert scale (LS) was used (1 = worst, 4 = best). Surveys were done on Day 20, Day 45, and after nine months of implementation of. Responses of emergency care providers were compiled and analyzed using SPSS version 16.
Results
Three surveys consisted of 22 participants in each survey. The survey domain of usability improved on Survey 3 (LS = 2.57), Survey 2 (LS = 2.46), Survey 1 (LS = 2.24). Application of EMR improved from Survey 1 to Survey 3. The data regarding perception of security concerns such as manipulation of data, transparency, and accountability were comparable among Survey 1, Survey 2, and Survey 3. Initial satisfaction was strongly associated with perception of usefulness of data mining for research purposes.
Conclusions
Satisfaction with an EMR system at its implementation generally persisted through the first year of use. Implementation plans must include positive reinforcement regarding EMR among emergency care providers.