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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 $\beta = 3.2\,\%$.
Transfers of resources in dictator games vary significantly by the characteristics of recipients. We focus on social norms and demonstrate that variation in the recipient changes both giving and injunctive norms and may offer an explanation for differences in giving. We elicit generosity using dictator games, and social norms using incentivized coordination games, with two different recipient types: an anonymous student and a charitable organization. A within-subjects design ensures that other factors are held constant. Our results show that differences in giving behavior are closely related to differences in social norms of giving across contexts. Controlling for individual differences in beliefs about the norm, subjects do not weight compliance with the norms in the student recipient or charity recipient dictator game differently. These results suggest that the impact of context on giving co-occurs with an impact on social norms.
Glauconites occurring within the Ukra Member of Kutch Basin have remained unexplored in terms of their economic significance. The present study aimed to present a detailed physicochemical characterization of glauconite occurring in the siliciclastic rocks of Guneri and Umarsar area of the Kutch district, Gujarat, India to explore their economic potential. The study involved an integrated petrographical, mineralogical, and geochemical investigation of glauconitic rocks to highlight the occurrence, nature, and maturity of glauconite. The characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence (XRF), and electron probe microanalysis (EPMA) combined with energy dispersive X-ray (EDX), Field emission gun scanning electron microscopy (FEG-SEM), Fourier-transform infrared spectroscopy (FTIR), and inductively coupled plasma mass spectroscopy (ICP-MS). Petrographic and bulk XRD analysis revealed that the glauconite occurs as green pellets constituting ~30 and 40% of the glauconitic sandstone and shale, respectively. Whole-rock analysis showed that the value of K2O varies considerably from 3.93 wt.% (sandstone) to 5.63 wt.% (shale). Mineral chemistry indicated the distinctive chemical composition of glauconite pellets containing 7.4–8.4 wt.% of K2O. The parameters, such as the distance between the (001) and (020) peaks and the large K2O content (~8 wt.%) of the glauconite fraction reflect an evolved to highly evolved stage of maturation. The morphological and spectral signatures further support the high degree of maturation in glauconites. Trace-element analysis implied that the glauconitic sandstone and shale contain elements such as Zn, Mn, Cu, Co, Mo, and Ni, which serve as essential micronutrients for plants. These data sets collectively constitute part of a preliminary study which is prerequisite to beneficiation, but further evaluation of its potential as a potash fertilizer also is needed.
Water is often referred to as our most precious resource, and for a good reason – drinking water and wastewater services sustain core functions of the critical infrastructure, communities, and human life itself. Our water systems are threatened by aging infrastructure, floods, drought, storms, earthquakes, sea level rise, population growth, cyber-security breaches, and pollution, often in combination. Marginalized communities inevitably feel the worst impacts, and our response continues to be hampered by fragmented and antiquated governance and management practices. This paper focuses on the resilience of water sector (drinking water, wastewater, and stormwater [DWS]) to three major hazards (Sea-Level Rise, Earthquake, and Cyberattack). The purpose of this paper is to provide information useful for creating and maintaining resilient water system services. The term resilience describes the ability to adapt to changing conditions and to withstand and recover from disruptions. The resilience of DWS systems is of utmost importance to modern societies that are highly dependent on continued access to these water sector services. This review covers the terminology on water sector resilience and the assessment of a broad landscape of threats mapped with the proposed framework. A more detailed discussion on two areas of resilience is given: Physical Resilience, which is currently a major factor influencing disruptions and failures in DWS systems, and Digital Resilience, which is a rapidly increasing concern for modern infrastructure systems. The resilience of DWS systems should be considered holistically, inclusive of social, digital, and physical systems. The framework integrates various perspectives on water system threats by showcasing interactions between the parts of the DWS systems and their environment. While the challenges of change, shock and stresses are inevitable, embracing a social–ecological–technical system-of-systems and whole-life approach will allow us to better understand and operationalize resilience.
The Eastern Gangetic Plains (EGP) hosts three actively aggradational megafans, the Teesta, Kosi, and Gandak, which are directly fed by rivers draining the Himalayan Mountains in the north; and a fourth, the Sone, which is fed from the Indian shield in the south. Topography in the Western Gangetic Plains (WGP) consists instead of a 900-km-long and 100-km-wide raised interfluve between the incised valleys of the Yamuna and Ganga rivers. None of the commonly-advocated megafan criteria, such as mappable fluvial sediment entities with an apex, distributary drainage, convex-up transverse topographic profiles, or a distinct fan boundary with a break in slope, seem to apply. There are thus no active megafans in the WGP. While not ruling out the possible occurrence of relict megafans, evidence suggests that the WGP landscape is essentially a coalescing floodplain in a valley–interfluve setting. Contrasts between the EGP and WGP are controlled by (i) differential late Quaternary and Holocene basin subsidence, which governs regional-scale variations in accommodation space; (ii) along-strike tectonic and climatic variability, primarily reflected in differential uplift rates, rainfall gradients, mountain-front tectonics, and river exit-point spacing; and (iii) hydrological characteristics of the feeder channel manifested as variability in stream power and sediment flux.
This study aimed to evaluate the management practices and outcomes in children with sinogenic intracranial suppuration.
Method
This was a retrospective cohort study in a single paediatric tertiary unit that included patients younger than 18 years with radiologically confirmed intracranial abscess, including subdural empyema and epidural or intraparenchymal abscess secondary to sinusitis. Main outcomes studied were rate of return to the operating theatre, length of hospital stay, death in less than 90 days and neurological disability at 6 months.
Results
A cohort of 39 consecutive patients presenting between 2000 and 2020 were eligible for inclusion. Subdural empyema was the most common intracranial complication followed by extradural abscess and intraparenchymal abscess. Mean length of hospital stay was 42 days. Sixteen patients were managed with combined ENT and neurosurgical interventions, 15 patients underwent ENT procedures alone and 4 patients had only neurosurgical drainage. Four patients initially underwent non-operative management. The rates of return to the operating theatre, neurological deficits and 90-day mortality were 19, 9 and 3, respectively, and were comparable across the 4 treatment arms. In the univariate logistic regression, only the size of an intracranial abscess was found be associated with an increased likelihood of return to the operating theatre, whereas combined ENT and neurosurgical intervention did not result in improved outcomes.
Conclusion
Sinogenic intracranial abscesses are associated with significant morbidity and mortality. The size of an intracranial abscess has a strong association with a need for a revision surgery.
This study aimed to characterise the ipsilateral, contralateral and bilateral masseter vestibular-evoked myogenic potential using clicks and 500 Hz tone burst stimuli in healthy adults.
Method
Masseter vestibular-evoked myogenic potential was recorded from 20 healthy participants aged 19–28 years (11 males and 9 females). Masseter vestibular-evoked myogenic potential was recorded using 500 Hz tone burst and click stimuli in ipsilateral, contralateral and bilateral modes.
Results
A statistically significant difference was observed between ipsilateral and contralateral stimulation for p11 latency, n21 latency and p11-n21 amplitude for both click and 500 Hz tone burst stimuli. The amplitude of the p11-n21 complex was higher for ipsilateral, contralateral and bilateral stimulations for 500 Hz tone burst than for click stimulus.
Conclusion
This study showed a significant difference for p11-n21 amplitude between click and 500 Hz tone burst evoked masseter vestibular-evoked myogenic potential. In addition, bilateral stimulation elicited a larger response than ipsilateral and contralateral stimulation.
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.
The North Purulia Shear Zone that dissects the granulite basement of the Chotanagpur Granite Gneissic Complex of the East Indian Shield exposes a deformed and metamorphosed nepheline syenite. The studied ‘foid-monzosyenite’ shows high abundances of large ion lithophile elements and high field strength elements with low abundances of compatible elements. Trace-element signatures show negative U, Th, Zr, Ti and Pb and positive Sr, Ba and Eu anomalies with respect to the primitive mantle. The chondrite-normalized diagram shows strongly fractionated rare earth element patterns ((La/Lu)N ∼23–87). Geochemical fingerprints suggest that the basanitic protolith was formed by low-degree partial melting of garnet peridotite in the sub-continental lithospheric mantle. The enriched large ion lithophile, high field strength element and light rare earth element concentrations (relative to primitive mantle) can be explained by a mixed mantle source with components from a previously deformed alkaline rock/carbonatite. Geochemical data do not support any significant crustal contamination and suggest variable fractionation of clinopyroxene, ilmenite, titanite and apatite from the parental melt. Petrological data are consistent with the view that the nepheline syenite magma was emplaced in a rift setting with a minimum temperature of 800–900°C, low fO2 conditions (below the fayalite–magnetite–quartz buffer) at a mid-crustal depth between 950 and 900 Ma. The continental rift zone, however, did not lead to the formation of an open ocean basin. Subsequently, the studied rock and its basement was deformed and metamorphosed in a continent–continent collisional setting at ∼900 Ma. Combining information from the other Indian occurrences with this study, it is demonstrated that the deformed alkaline rocks and carbonatite are potentially valuable for tracing the birth and demise of the palaeo-supercontinents.
On the western part of the eastern Indian shield, Archaean basement (Bonai granite) is overlain by radioactive conglomerate. The conglomerate contains well-rounded, fractured Mg-poor (<0.18 wt.% MgO), Al-rich (up to 21.14 wt.% Al2O3) Zn-rich chromite (>35.0 wt.% Cr2O3) containing up to 15.5 wt.% ZnO. This is the first reported occurrence of detrital zinc-rich chromite having such unusually high ZnO from India, and to our knowledge, the third reported occurrence in radioactive quartz-pebble conglomerate after Witwatersrand, South Africa and Tarkwa, Ghana. Zinc-rich chromite grains are either clean or contain exsolution blebs/lamella of rutile. The conglomerates show evidence for post-depositional hydrothermal fluid influx and fluid-induced mineral alteration. The strong negative correlation between Zn and Fe2+, Al and Cr, and Al and Fe3+, and strong positive correlation between Zn and Al suggest secondary incorporation of Zn and Al by substitution of Fe2+ and Cr (and Fe3+), respectively, leading to partial transformation of (Fe)(Cr,Al,Fe3+)2O4 towards ZnAl2O4 composition. The chromite grains were possibly derived from komatiite. The timing of Zn enrichment, either at the provenance prior to sedimentation, or at the depositional site post-dating sedimentation, remains unresolved.
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.
In view of the COVID-19 surge, the construction of the Burns and Plastic Surgery Block at AIIMS, New Delhi was expedited at war footing level and converted into a COVID-19 Emergency response Centre (ERC). Engineering works were completed in a speedy manner and various patient care areas were equipped as deemed necessary for providing tertiary care to COVID-19 patients. A highly spirited team comprising of Emergency Medicine Specialists, Anesthesia and Critical Care specialist, Hospital Administrators and Nursing Officers was formed. Effective segregation of patient care areas into clean, contaminated, and intermediate zones was done using physical barriers and air conditioning modifications. The screening area for patients suspected of having COVID-19 was created in addition to a 2-step process i.e., Triage 1 and Triage 2, thereafter, patients requiring admission would be referred to the emergency area. An in-house designed and fabricated sampling booth was created to bring down the use of PPEs and for better infection control. The ERC has a general ward and state of the art intensive care units. Mobilizing resources (machinery, manpower, consumables etc.) during the lockdown required commitment from top leadership, motivated teams, expeditious procurement, coordination with multiple agencies working on site, expediting statutory clearances, coordination with police services, transportation of labor etc.
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.