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This work describes the mineralogy of dolomite carbonatite occurring at the Newania carbonatite complex, Rajasthan, north-western India. The mineralogy records the textural and compositional features of magmatic and post-magmatic stages of carbonatite evolution. Ferroan dolomite is the principal constituent and displays variable degrees of deformation, ranging from brittle-to-ductile deformation regimes. Apatite exhibits textural and compositional evolutionary trends from early-to-late stages of carbonatite evolution. Two varieties of amphibole are reported for the first time from this complex, ferri-winchite and cummingtonite; the former is magmatic and the latter is metamorphic in origin. The columbite–tantalite-series minerals are columbite-(Fe), and their paragenesis evolves from composite grains with pyrochlore to individual crystals. Pyrochlore is magmatic with U–Ta–Ti-rich compositions and shows evolution from calciopyrochlore to kenopyrochlore, followed by alteration during late-stages of carbonatite evolution. Monazite and baryte constitute the post-magmatic mineral assemblage; the former is hydrothermal and crystallised after precursor apatite, whereas the latter is associated exclusively with columbite–pyrochlore composites. On the basis of the mineralogy of the carbonatite, it is concluded that the parent magma was generated by low-degree partial melting of magnesite–phlogopite-bearing peridotite.
The fifth season of excavations of Oponice Castle in 2020 was located in the lower castle’s courtyard. The research led to discovery of an original clay floor being heavily burned with charred plank and a rectangular stone-brick construction. The construction has collapsed upper part with a fallen low brick arch. The whole area was covered with numerous stove tiles and one clay mold for the production of stove tiles. The construction was identified as a pottery kiln dated to the second half of the 16th until the first half of the 17th century AD by the findings from excavated layer identified to the kiln destruction. Also, written sources mention a large fire in 1645 which destroyed the castle. The aim of this article is to use different methods of dating and refine the chronology of the context through microarchaeology and Bayesian modeling. For these purposes different types of samples were collected. The sampling focused on site formation process determination of pottery kiln use and the way of its destruction. Applying Bayesian analysis improved overall dating, through modeled time interval of the three individual sequences and helped recreated historical events during the period, when the calibration curve fluctuates.
Marstrand’s theorem states that applying a generic rotation to a planar set A before projecting it orthogonally to the x-axis almost surely gives an image with the maximal possible dimension $\min(1, \dim A)$. We first prove, using the transversality theory of Peres–Schlag locally, that the same result holds when applying a generic complex linear-fractional transformation in $PSL(2,\mathbb{C})$ or a generic real linear-fractional transformation in $PGL(3,\mathbb{R})$. We next show that, under some necessary technical assumptions, transversality locally holds for restricted families of projections corresponding to one-dimensional subgroups of $PSL(2,\mathbb{C})$ or $PGL(3,\mathbb{R})$. Third, we demonstrate, in any dimension, local transversality and resulting projection statements for the families of closest-point projections to totally-geodesic subspaces of hyperbolic and spherical geometries.
Usually focusing on linguistic/semiotic signs in culturally and linguistically diverse communities, linguistic landscape (hereafter LL) has appeared as a methodological paradigm for the investigation of the representation and visibility of languages across geographical contexts (Landry & Bourhis, 1997; Scollon & Scollon, 2003). Highlighting the informative and symbolic functions of languages, this paradigm enables the combination of a quantitatively distributive lens with a refined ethnographic perspective to generate insights into the ethnolinguistic vitality of a given territory and the spread of international lingua francas – in most cases English – in localized settings (Backhaus, 2007; Jaworski & Thurlow, 2010; Li, 2015).
Many social interventions have been developed with the hopes of reducing and preventing social isolation among older people (e.g., recreation, arts-based programs and social prescription). Friendly visiting programs, also known as befriending schemes, have been a mainstay in this area for decades and are largely thought to be effective at reconnecting older people (≥ 60 years of age) experiencing isolation. Research and evaluations have yet to determine, however, how and why these programs may be most successful, and under what conditions. This article presents the findings of a realist synthesis aimed at identifying the critical mechanisms and contextual factors that lead to successful outcomes in friendly visiting programs. Seven studies are synthesized to inform a friendly visiting program theory accounting for key mechanisms (e.g., provision of informal support) and underlying contexts (e.g., training of volunteers) that can be used to inform future programs. Recommendations for future research are also presented.
This paper studies the contradictions of peasant politics in Sri Lanka’s dry zone frontier in a highly militarized colonization scheme (‘System L’ of the Mahaweli Development Programme in Weli Oya in northern Sri Lanka). Through a detailed ethnographic study of the life histories of settlers who came in two waves to this scheme (1980s and post-2009), we show the workings of what we call the ‘lure of land’: first, as the (al)lure that attracts landless families to live out the mythical dream of becoming a paddy farmer; second, this lure of land is intimately tied to a nationalist territorial aspiration that transforms the settler into a patriotic colonizer of the land: due to its strategic location in the frontier zone between Sinhalese and Tamil inhabited territories, settlers became ‘home guards’ who live on and protect the frontier. But the lure of land is not without contradictions: Life in the frontier is dangerous (for the early settlers) and economically precarious (for the early and late settlers), because the state is unable to deliver the promise of land and water. Government officials deploy various tactics of repeatedly deferred promises and subtle threats to discourage settlers to abandon the colonization scheme despite the settlers’ precarious life conditions, disappointments, and frustrations. A ‘cunning state’ thereby betrays its own ‘frontiersmen’, while safeguarding its nationalist territorial agenda.
Two-dimensional numerical simulations with the particle tracking method were conducted to analyse the dispersion behind the detonation front and its mean structure. The mixtures were 2H$_2$–O$_2$–7Ar and 2H$_2$–O$_2$ of increased irregularity in ambient conditions. The detonation could be described as a two-scale phenomenon, especially for the unstable case. The first scale is related to the main heat release zone, and the second where some classical laws of turbulence remain relevant. The dispersion of the particles was promoted by the fluctuations of the leading shock and its curvature, the presence of the reaction front, and to a lesser extent transverse waves, jets and vortex motion. Indeed, the dispersion and the relative dispersion could be scaled using the reduced activation energy and the $\chi$ parameter, respectively, suggesting that the main mechanism driving the dispersion came from the one-dimensional leading shock fluctuations and heat release. The dispersion within the induction time scale was closely related to the cellular structure, particles accumulating along the trajectory of the triple points. Then, after a transient where the fading transverse waves and the vortical motions coming from jets and slip lines were present, the relative dispersion relaxed towards a Richardson–Obukhov regime, especially for the unstable case. Two new Lagrangian Favre average procedures for the gaseous detonation in the instantaneous shock frame were proposed and the mean profiles were compared with those from Eulerian procedure. The characteristic lengths for the detonation were similar, meaning that the Eulerian procedure gave the mean structure with a reasonable accuracy.
We experimentally study front propagation in a vortex lattice providing closed steady cellular flows and no mean flow. To this end, we trigger an autocatalytic reaction in a solution stirred by magnetohydrodynamic flows in a Hele-Shaw cell. We evidence a scale-invariant regime below some flow magnitude and a scale-dependent regime above, the scales referring here to the vortex scale and the front thickness. The transition between these regimes corresponds to a unitary Damköhler number $Da$: $Da=1$. The enhancement of the mean front velocity with the flow magnitude nicely agrees with the literature on numerical simulations and theoretical analyses in the scale-invariant regime $Da>1$, but displays noticeable discrepancies in the scale-dependent one $Da<1$. This shows that the transition between regimes is qualitatively sharp but quantitatively smooth.
Engaging communities is a key factor in efficient response to public health emergencies (PHE). Previous and recent outbreaks have shown that civil society organizations (CSOs) can mobilize the communities to better prepare and respond to a PHE. Consequently, the World Health Organization (WHO) Regional Office for Africa (AFRO) implemented an initiative to partner with community leaders by engaging CSOs. The Civil Society Organization Initiative (CSO Initiative) aims to work directly with well-established community-based organizations to accelerate whole-of-society preparation and response. Twenty-three CSOs from 12 WHO African Region Member States have been supported financially and technically to implement effective community-based interventions to respond to the coronavirus disease (COVID-19) pandemic. After 1 year of implementation (2021), the successes, challenges, and recommendations for maximizing future engagements with CSOs are outlined. As the COVID-19 outbreak is again underlining, partnering with established CSOs to engage diverse social groups from various communities can help provide a timely and efficient response to a PHE.
We investigate the dynamics of a low-density round jet, with a focus on the mechanisms governing the turbulent momentum and mass transfers as well as on the entrainment of ambient fluid. To that purpose, we combine a theoretical analysis, laboratory experiments and numerical simulations. The theoretical analysis relies on a general formulation of the entrainment decomposition for the case of large density differences, revealing the role of the processes contributing to the entrainment: turbulent kinetic energy production and variation in the shape of the mean velocity radial profiles. The spatial evolution of these terms has been evaluated by means of challenging experiments, providing a unique data set of combined velocity and density statistics of a low-density jet and an air jet. The same flows are investigated by means of large-eddy simulation (LES). Other than for providing complementary information on flow statistics, LES is here used to investigate the role of varying conditions imposed at the source, notably concerning the shape of the inlet velocity profile and the presence of a bottom wall surrounding the source. Experimental and numerical results provide clear insight on how a reduced density within the jet enhances the turbulent kinetic energy production (compared to an iso-density jet) and modifies the shape of the mean velocity profiles. Despite its clear influence on the flow statistics, the reduced density has overall little influence on the entrainment rate, which also shows little sensitivity to varying source conditions.
Assuming the existence of a monster model, tameness, and continuity of nonsplitting in an abstract elementary class (AEC), we extend known superstability results: let $\mu>\operatorname {LS}(\mathbf {K})$ be a regular stability cardinal and let $\chi $ be the local character of $\mu $-nonsplitting. The following holds:
1. When $\mu $-nonforking is restricted to $(\mu ,\geq \chi )$-limit models ordered by universal extensions, it enjoys invariance, monotonicity, uniqueness, existence, extension, and continuity. It also has local character $\chi $. This generalizes Vasey’s result [37, Corollary 13.16] which assumed $\mu $-superstability to obtain same properties but with local character $\aleph _0$.
2. There is $\lambda \in [\mu ,h(\mu ))$ such that if $\mathbf {K}$ is stable in every cardinal between $\mu $ and $\lambda $, then $\mathbf {K}$ has $\mu $-symmetry while $\mu $-nonforking in (1) has symmetry. In this case:
(a)$\mathbf {K}$ has the uniqueness of $(\mu ,\geq \chi )$-limit models: if $M_1,M_2$ are both $(\mu ,\geq \chi )$-limit over some $M_0\in K_{\mu }$, then $M_1\cong _{M_0}M_2$;
(b) any increasing chain of $\mu ^+$-saturated models of length $\geq \chi $ has a $\mu ^+$-saturated union. These generalize [31] and remove the symmetry assumption in [10, 38] .
Under $(<\mu )$-tameness, the conclusions of (1), (2)(a)(b) are equivalent to $\mathbf {K}$ having the $\chi $-local character of $\mu $-nonsplitting.
Grossberg and Vasey [18, 38] gave eventual superstability criteria for tame AECs with a monster model. We remove the high cardinal threshold and reduce the cardinal jump between equivalent superstability criteria. We also add two new superstability criteria to the list: a weaker version of solvability and the boundedness of the U-rank.
Research on interorganisational collaboration is longstanding however the role leadership plays in such collaborations is often neglected. Using grounded theory, we present a process model of ‘leadership by cavea’ whereby the relationships across organisations involved in a collaborative project were structured according to hierarchies of privilege, determined by the inherent power of ‘bonding’ social capital. While it emerged that cultural capital was a more valuable resource, this was recognised too late in the leadership process for it to make a necessary contribution. Our findings demonstrate that when seeking to practice collaborative leadership across organisations, individuals and the organisations they represent must be aware of the power they hold and wield, even needing to share or relinquish power to ensure that hierarchies of privilege do not hinder efforts to achieve mutual goals.
This study proposes a new reconstruction of the tripod that Pausanias (1.18.8) recorded in the Olympieion at Athens. According to his brief description, the bronze tripod was supported by Persians made from Phrygian marble. A sculptor's sketch found during the excavations of the Athenian Agora is identified as a representation of that monument. The sketch, carved from poros limestone, depicts a standing male figure dressed in eastern attire supporting the foot of a tripod. The figural type finds its closest parallels among the colossal statues from the Forum of Trajan in Rome, suggesting a new date and context for the monument in the Olympieion. The scenario favoured here is that the tripod was dedicated following Trajan's victories in Parthia, perhaps completed or commissioned by Hadrian. Cassius Dio (68.17.2) records that Trajan departed for his Parthian campaigns from Athens, where memories of Persian defeat were actively curated.
For a nonempty set A of integers and an integer n, let $r_{A}(n)$ be the number of representations of n in the form $n=a+a'$, where $a\leqslant a'$ and $a, a'\in A$, and $d_{A}(n)$ be the number of representations of n in the form $n=a-a'$, where $a, a'\in A$. The binary support of a positive integer n is defined as the subset S(n) of nonnegative integers consisting of the exponents in the binary expansion of n, i.e., $n=\sum_{i\in S(n)} 2^i$, $S(-n)=-S(n)$ and $S(0)=\emptyset$. For real number x, let $A(-x,x)$ be the number of elements $a\in A$ with $-x\leqslant a\leqslant x$. The famous Erdős-Turán Conjecture states that if A is a set of positive integers such that $r_A(n)\geqslant 1$ for all sufficiently large n, then $\limsup_{n\rightarrow\infty}r_A(n)=\infty$. In 2004, Nešetřil and Serra initially introduced the notation of “bounded” property and confirmed the Erdős-Turán conjecture for a class of bounded bases. They also proved that, there exists a set A of integers satisfying $r_A(n)=1$ for all integers n and $|S(x)\bigcup S(y)|\leqslant 4|S(x+y)|$ for $x,y\in A$. On the other hand, Nathanson proved that there exists a set A of integers such that $r_A(n)=1$ for all integers n and $2\log x/\log 5+c_1\leqslant A(-x,x)\leqslant 2\log x/\log 3+c_2$ for all $x\geqslant 1$, where $c_1,c_2$ are absolute constants. In this paper, following these results, we prove that, there exists a set A of integers such that: $r_A(n)=1$ for all integers n and $d_A(n)=1$ for all positive integers n, $|S(x)\bigcup S(y)|\leqslant 4|S(x+y)|$ for $x,y\in A$ and $A(-x,x) \gt (4/\log 5)\log\log x+c$ for all $x\geqslant 1$, where c is an absolute constant. Furthermore, we also construct a family of arbitrarily spare such sets A.
Extensive research in Western societies has demonstrated that media reports of protests have succumbed to selection and description biases, but such tendencies have not yet been tested in the Chinese context. This article investigates the Chinese government and news media's selection and description bias in domestic protest events reporting. Using a large protest event data set from Weibo (CASM-China), we found that government accounts on Weibo covered only 0.4 per cent of protests while news media accounts covered 6.3 per cent of them. In selecting events for coverage, the news media accounts tacitly struck a balance between newsworthiness and political sensitivity; this led them to gravitate towards protests by underprivileged social groups and shy away from protests targeting the government. Government accounts on Weibo, on the other hand, eschewed reporting on violent protests and those organized by the urban middle class and veterans. In reporting selected protest events, both government and news media accounts tended to depoliticize protest events and to frame them in a more positive tone. This description bias was more pronounced for the government than the news media accounts. The government coverage of protest events also had a more thematic (as opposed to episodic) orientation than the news media.
Emergency department (ED) staff in Belgium is simultaneously involved in patient care in the ED and in prehospital interventions as part of a Mobile Medical Team (MMT) or a Paramedic Intervention Team (PIT). There is a growing concern that the MMT is often over-qualified for the prehospital interventions they are dispatched to, while their absence from the ED results in insufficient human resources there.
Objective:
The current study aims to investigate whether this perception is correct in the EDs of two different regions, while also examining the differences between a two-tiered (2T) and a three-tiered (3T) Emergency Medical Services (EMS) region.
Methods:
A specially developed and pre-tested registration form was completed by physicians and nurses before and after each MMT intervention. The form included information on the composition of the MMT, the perceived need for MMT intervention pre-departure from the ED, the subjective appreciation of the need for the MMT after an intervention, and the therapeutic intervention(s) performed, in order to obtain a more objective appreciation of the actual need for an MMT. Data from a 2T and a 3T region were analyzed to rate the appropriateness of the interventions.
Results:
Although the 2T and 3T regions showed differences regarding MMT composition, dispatching, and logistics, the outcome of the study was identical in both regions. Before the intervention, physicians and nurses estimated that the MMT intervention would not be necessary in 37.7% of cases. However, following the intervention, it was subjectively deemed unnecessary in 65.7% of cases. Based on therapeutic interventions performed, the MMT was viewed as being over-qualified for carrying these out in 85.6% of cases. Post-intervention, the initial prediction that the MMT was over-qualified for the call was confirmed by the same physicians and nurses in 87.6% of cases, whilst their prediction was correct in 92.8% of cases in terms of the intervention that was carried out.
Conclusion:
In two different Belgian regions, the MMT is over-qualified in a vast majority of interventions. Physicians and nurses within the MMT can generally already predict that the MMT is over-qualified when leaving the ED. These findings suggest that there may be significant opportunities to improve the efficacy of human resources in the ED once there are less interventions carried out by an over-qualified MMT.
Saccular aneurysms of the aorta in childhood are rare, and the low incidence of aortic aneurysms among children limits our understanding of their aetiology and surgical indications. In this case report, we describe the successful surgical treatment of a 5-year-old boy with severe aortic valvular stenosis, supra-valvular aortic stenosis, and a large saccular aneurysm in the anterior wall of the ascending aorta, without any connective tissue disorder.
Major efforts to control the population of Aedes aegypti mosquitoes involve the use of synthetic insecticides, which can be harmful to the environment. Most plant compounds are eco-friendly and some of them have biocontrol potential, whereas a fraction of these compounds is released into the environment through the leaf-leaching process. We evaluated the effects of secondary compounds from Ateleia glazioviana and Eucalyptus grandis senescent leaf leachates on Ae. aegypti larval mortality, adult emergence time, and wing size using a microcosm approach. The microcosms consisted of 10 larvae kept in water (control) and under four treatments with leachates from a combination of plant species and leaching time (7 or 14 days). Chemical analyses of the leachates showed the presence of carboxaldehyde and Heptatriocotanol, which have antimicrobial properties, potentially reducing the food available for larvae. β-Sitosterol, Stigmasterol, α-Amyrin, and Lupeol are compounds with inhibitory, neurotoxic, and larvicidal effects. Both plant species’ leachates increased larval mortality and decreased emergence time due to the presence of compounds toxic to the larvae. Larger organisms emerged in treatments with 7-days leachates, likely due to the high concentration of dissolved organic matter in the leachates. The higher mortality in 7-days leachates may also increase the organic matter from co-specific decomposition, improving adult size. Therefore, if the mosquito population is not locally extinct, compounds present in leaf leachates may act as a resource enhancing larvae growth, potentially increasing survivors’ fitness. In conclusion, biocontrol attempts using urban green spaces may have unexpected outcomes, such as resulting in larger pest organisms.
Health care provision depends on reliable critical infrastructure (CI) to power equipment and to provide water for medication and sanitation. Attacks on CI limiting such functions can have a profound and prolonged influence on delivery of care.
Methods:
A retrospective analysis of the Global Terrorism Database (GTD) was performed of all attacks occurring from 1970-2020. Data were filtered using the internal database search function for all events where the primary target was “Utilities,” “Food or Water Supply,” and “Telecommunications.” For the purposes of this study, the subtype “Food Supply” was excluded. Events were collated based on year, country, region, and numbers killed and wounded.
Results:
The GTD listed 7,813 attacks on CI, with 6,280 of those attacks targeting utilities, leading to 1,917 persons directly killed and 1,377 persons wounded. In total, there were 1,265 attacks targeting telecommunications causing 205 direct deaths and 510 wounded. Lastly, 268 attacks targeted the water supply with 318 directly killed and 261 wounded. Regionally, South America had the most attacks with 2,236, followed by Central America and the Caribbean with 1,390. Based on infrastructure type, the most attacks on utilities occurred in El Salvador (1,061), and the most attacks on telecommunications were in India (140). Peru (46) had the most attacks on its water supply.
Conclusion:
The regions with the highest number of total attacks targeting CI have historically been in South America, with more attacks against power and utilities than other infrastructure. Although the numbers of persons directly killed and wounded in these attacks were lower than with other target types, the true impacts on lack of health care delivery are not accounted for in these numbers. By understanding the pattern and scope of these attacks, Counter-Terrorism Medicine (CTM) initiatives can be created to target-harden health care-related infrastructure.