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In this chapter the “Pashtun Borderland” – a key concept throughout the book – is framed as a distinct physical and geopolitical space. This space, it is argued, is shaped by the complex interplay of imperial aspiration by larger polities claiming their authority over this space and ethnic self-ascriptions arising as a consequence. The heavy ideological baggage both practices pivot on is somewhat disenchanted by significant lines of conflict which traverse the region and its communities: between lowland and upland communities, between local elites and subalterns and between urban and rural communities. It is claimed that the persona of the discontent, or troublemaker, is a systemic result of these complex constellations, heavily fuelled by the agendas of successive imperial actors and the making and un-making of temporary pragmatic alliances typical for this kind of environment, ideal-typically cast here as “Borderland pragmatics”.
Proteins are vital biological macromolecules that execute biological functions and form the core of synthetic biological systems. The history of de novo protein has evolved from initial successes in subordinate structural design to more intricate protein creation, challenging the complexities of natural proteins. Recent strides in protein design have leveraged computational methods to craft proteins for functions beyond their natural capabilities. Molecular dynamics (MD) simulations have emerged as a crucial tool for comprehending the structural and dynamic properties of de novo-designed proteins. In this study, we examined the pivotal role of MD simulations in elucidating the sampling methods, force field, water models, stability, and dynamics of de novo-designed proteins, highlighting their potential applications in diverse fields. The synergy between computational modeling and experimental validation continued to play a crucial role in the creation of novel proteins tailored for specific functions and applications.
Three-dimensional short-crested water waves are known to host harmonic resonances (HRs). Their existence depends on their sporadicity versus their persistency. Previous studies, using a unique yet hybrid solution, suggested that HRs exhibit sporadic instability, with the domain of instability exhibiting a bubble-like structure which experiences a loss of stability followed by a re-stabilization. Through the calculation of their complete multiple solution structures and normal forms, we discuss the particular harmonic resonance (2,6). The (2,6) resonance was chosen, not only because it is of lower order, and thus more likely to be significant, but also because it is representative of a fully developed three-dimensional water wave field. Its appearance, growth rate and persistency are discussed. On our converged solutions, we show that, at an incidence angle for which HR (2,6) occurs, the associated superharmonic instability is no longer sporadic. It was also found that the multiple solution operates a subcritical pitchfork bifurcation, so regardless of the value of the control parameter, the wave steepness, a stable branch of the solution always exists. As a result, the analysis reveals two competing processes that either provoke and enhance HRs, or inhibit their appearance and development.
This chapter explores the resulting party identification in the three cases. Drawing on original and existing survey data, it shows that membership in organizations that regularly support a new party is strongly associated with whether a voter develops an attachment to the party. Further analysis of the poster experiments suggests that the frequency of attending organization meetings is associated with the robustness of the attachment. Additional analyses of the natural experiment reveal that repeated organizational expressions of support over multiple years help new parties gain new followers. It then compares and contrasts this organizationally mediated path to partisanship (organizational cultivation), which can account for the development of robust partisan attachments to the MAS and MORENA, with an alternative path to partisanship that can yield party identification even for parties without organically linked organizational allies. In the case of Alianza PAIS, which could not rely on organizational cultivation through organically linked organizations, partisan attachments have developed in direct response to voters’ evaluations of the party’s performance.
We analyze the limit of stable solutions to the Ginzburg-Landau (GL) equations when ${\varepsilon }$, the inverse of the GL parameter, goes to zero and in a regime where the applied magnetic field is of order $|\log {\varepsilon } |$ whereas the total energy is of order $|\log {\varepsilon }|^2$. In order to do that, we pass to the limit in the second inner variation of the GL energy. The main difficulty is to understand the convergence of quadratic terms involving derivatives of functions converging only weakly in $H^1$. We use an assumption of convergence of energies, the limiting criticality conditions obtained by Sandier-Serfaty by passing to the limit in the first inner variation, and properties of limiting vorticities to find the limit of all the desired quadratic terms. At last, we investigate the limiting stability condition we have obtained. In the case with magnetic field, we study an example of an admissible limiting vorticity supported on a line in a square ${{\Omega }}=(-L,L)^2$ and show that if L is small enough, this vorticiy satisfies the limiting stability condition, whereas when L is large enough, it stops verifying that condition. In the case without magnetic field, we use a result of Iwaniec-Onninen to prove that every measure in $H^{-1}({{\Omega }})$ satisfying the first-order limiting criticality condition also verifies the second-order limiting stability condition.
The fixed points of the generalized Ricci flow are the Bismut Ricci flat (BRF) metrics, i.e., a generalized metric (g, H) on a manifold M, where g is a Riemannian metric and H a closed 3-form, such that H is g-harmonic and $\operatorname{Rc}(g)=\tfrac{1}{4} H_g^2$. Given two standard Einstein homogeneous spaces $G_i/K$, where each Gi is a compact simple Lie group and K is a closed subgroup of them holding some extra assumption, we consider $M=G_1\times G_2/\Delta K$. Recently, Lauret and Will proved the existence of a BRF metric on any of these spaces. We proved that this metric is always asymptotically stable for the generalized Ricci flow on M among a subset of G-invariant metrics and, if $G_1=G_2$, then it is globally stable.
The obligation of stability generally requires host States to maintain a relatively stable regulatory framework to mitigate political risks facing foreign investments. It has played a significant role in international investment tribunals’ review of host States’ renewable energy transition policies. This paper critically reviews tribunals’ interpretation of the obligation with a particular focus on the Spanish cases involving renewable energy incentive schemes. It canvasses the two ‘dimensions’ adopted by investment tribunals in the interpretation of stability, namely the protection of legitimate expectations and States’ right to regulate for public purposes. Examining the contents of the two dimensions separately, this paper argues that legal stability should be disentangled from the notion of legitimate expectations and be assessed through the reasonableness of regulatory changes per se. It further argues that an intrusive interpretation of legal stability lacks legal and institutional bases; instead, more deferential standards should be adopted in the review of renewable energy transition policies.
This paper studies the spatio-temporal dynamics of a diffusive plant-sulphide model with toxicity delay. More specifically, the effects of discrete delay and distributed delay on the dynamics are explored, respectively. The deep analysis of eigenvalues indicates that both diffusion and delay can induce Hopf bifurcations. The normal form theory is used to set up an exact formula that determines the properties of Hopf bifurcation in a diffusive plant-sulphide model. A sufficiently small discrete delay does not affect the stability and a sufficiently large discrete delay destabilizes the system. Nonetheless, a sufficiently small or large distributed delay does not affect the stability. Both delays cause instability by inducing Hopf bifurcation rather than Turing bifurcation.
This work aims to characterize and study the properties of an Algerian diatomaceous earth (Sig-Mascara) as a catalyst carrier. A commercial product of diatomite was characterized by granulometric analysis, X-ray fluorescence, X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis/differential scanning calorimetry and scanning electron microscopy/energy-dispersive X-ray spectroscopy methods. To purify the diatomite and remove the impurities (iron oxides, clay minerals, quartz and organic matters), the <63 μm fraction of the diatomite was separated out. The 15Ni/Ds-700 catalyst has lower SiO2, Al2O3 and CaO contents compared with the original diatomite. The NiO content of the catalyst is 15 wt.%, indicating successful impregnation. According to the nitrogen sorption–desorption results, the specific surface area of the purified diatomite particles (<63 μm) increased from 26.47 to 46.33 m2 g–1 compared to crude diatomite. The 15Ni/Ds-700 catalyst was applied in the dry reforming of methane to obtain synthesis gas (CO and H2). The results showed that the catalyst was relatively stable during catalytic measurements for 6 h, although the conversion rate value was low (12%).
Turmeric (Curcuma longa L.) is rich in curcuminoids, which are polyphenolic pigments make it one of the most valuable spice and medicinal plant. The rising need for natural colours and the numerous health advantages of curcuminoids are driving up the demand of turmeric. In this study, the effects of genotype and genotype × environment on the colour characteristics of 21 turmeric genotypes were examined in three different production environments namely vertical farming, greenhouse, and field conditions. The pooled analysis of variance revealed highly significant (P < 0.05) differences among genotypes (G), environments (E), and G × E interaction for three colour parameters [L* (lightness index), A* (redness index), B* (yellowness index)]. Among the genotypes, the values ranged from 41.80 to 54.76, 13.92 to 24.83 and 31.72 to 47.67 for L*, A*, B*, respectively. Erode Local (22.34), IISR Pragati (24.56) and IISR Prathiba (26.55) recorded maximum A* value under vertical farming, greenhouse, and field conditions, respectively. Correlation analysis between colour values and curcuminoids revealed a significant positive correlation (r = 0.608–0.735, P < 0.001) between A* value and curcuminoids. Furthermore, stability analysis for A* value revealed 78.87% genotype × environment interaction (GEI) from the first two principal components of GGE biplot. IISR Pragati and Waigon Turmeric are best was most stable for A* value across environments. Our study revealed that colour traits among genotypes vary widely and are strongly impacted by genetic and environmental factors. These findings are crucial for future breeding programs to enhance turmeric's colour, ensuring high-quality, stable products for producers and consumers.
Let ${\mathcal {R}} \subset \mathbb {P}^1_{\mathbb {C}}$ be a finite subset of markings. Let G be an almost simple simply-connected algebraic group over $\mathbb {C}$. Let $K_G$ denote the compact real form of G. Suppose for each lasso l around the marked point, a conjugacy class $C_l$ in $K_G$ is prescribed. The aim of this paper is to give verifiable criteria for the existence of an irreducible homomorphism of $\pi _{1}(\mathbb P^1_{\mathbb {C}} \,{\backslash}\, {\mathcal {R}})$ into $K_G$ such that the image of l lies in $C_l$.
This paper is focused on the stability of real-time hybrid aeroelastic simulation systems for flexible wings. In a hybrid aeroelastic simulation, a coupled aeroelastic system is ‘broken down’ into an aerodynamic simulation subsystem and a structural vibration testing subsystem. The coupling between structural dynamics and aerodynamics is achieved by real-time communication between the two subsystems. Real-time hybrid aeroelastic simulations can address the limitations associated with conventional aeroelastic testing performed within a wind tunnel or with pure computational aeroelastic simulation. However, as the coupling between structural dynamics and aerodynamics is completed through the real-time actuation and sensor measurement, their delays may inherently impact the performance of hybrid simulation system and subsequently alter the measured aeroelastic stability characteristics of the flexible wings. This study aims to quantify the impact of actuation and sensor measurement delays on the measured aeroelastic stability, e.g. the flutter boundary, of flexible wings during real-time hybrid simulations, especially when different aerodynamic models are implemented.
The tremendous biological diversity of some plant communities may be a reflection of the variety of direct and indirect interactions that plants have with predators, competitors, and mutualists. Ecologists have several ways of measuring biological diversity; some diversity indices, such as the Shannon index, integrate species richness and evenness. Alpha diversity measures species richness within an area, beta diversity measures species turnover, while gamma diversity is the combined species richness of all communities under consideration. Biotic and abiotic factors can influence community diversity directly and indirectly. For example, in southwest Finland, host plant abundance directly and positively influenced lepidopteran species abundance. In the African savanna, herbivorous mammals indirectly and negatively affected bird diversity by consuming trees and reducing the abundance of insects that served as food for the birds. Abiotic factors influencing community diversity include the type of habitat, geological heterogeneity, nutrient levels, and the type and intensity of disturbance. Ecologists predict that diverse communities will be more stable than less diverse communities, but that the populations of species in diverse communities will be less stable.
Analytical data from aqueous dissolution studies of minerals, mineral systems, and naturally equilibrated solutions such as surface waters and groundwaters provide the basic ingredients necessary to calculate comparative solubility (or activity) products (CKs) and comparative free energies of formation (CΔGf0) of possible minerals or hypothetical minerals. Using a thermodynamic approach, quasi-thermodynamic values are obtained which can help in understanding the relative stabilities of different but similar materials and changes in reacting systems. Illite equilibrated solutions demonstrated that: 1) there is a 5 kcal spread in comparative free energies of formation of the five illites used, 2) the comparative stabilities remain about the same when highly simplified but similar hypothetical mineral formulas are considered, and 3) some of these illites are probably not the most stable phase in a closed chemical system at standard temperature and pressure.
A “mineral index system” composed of common rock-forming minerals, products of chemical weathering and perhaps hypothetical minerals is proposed, which offers a means of studying naturally equilibrated solutions. Such a system can show changes with respect to CΔGf0 of these minerals at a particular site through time or in relationship to spatial distribution and geologic changes through synchronous sampling at different sites.
Mutual engagement between psycholinguistic and variationist sociolinguistic research is important: work to date shows quite different outcomes from these approaches. This chapter illustrates that, in general, heritage speakers maintain the grammaticalstructures and vocabulary of homeland varieties, in contradiction to widely held beliefs that language quickly “degrades” or is “bastardized” in immigrant communities, and in contradiction to many published studies about heritage languages. However, both approaches converge on finding change in one phonetic pattern in some of the languages analyzed. In this chapter, the potential sources of this apparent contradiction are explored, considering differences related to population, sample, methods of data collection, analysis, and predictors. This allows us to better understand whether, for example, reported “deficits” among heritage language speakers might be partly due to a deficit in test-taking and experience with formal contexts in the heritage language. It closes with a proposal for more coordinated work across methods.
Just 20 years ago, molecular biologists Leonie Ringrose and Renato Paro published an article provocatively entitled ‘Remembering Silence’. The article focused on how modified epigenetic elements could subsequently return to their silent state (i.e. their epigenetic status before experimental or environmentally induced modulation). Ringrose and Paro raised a question of considerable importance to expanding research in human neuroepigenetics, that of reversibility. For neuroepigeneticists interested in the molecular impact of environments on individuals’ biological profiles, including epigenetic modifications thought to be mediators between life trauma and risk of psychopathology, this question could be translated as: if you experience a traumatic event and thus acquire an epigenetic state considered pathological, can you free yourself of that state? In this chapter, we examine researchers’ ambitions to account for the indeterminacy of life and the speculative possibility of reversing acquired epigenetic states. Bringing together the perspectives of medical anthropology and molecular biology, we explore how reversibility – a return to silence – is envisioned, how therapeutic interventions purported to bring about that silence might function, and what this might mean for the mental health of people who live in the aftermath of trauma.
This chapter introduces state-space descriptions for computational graphs (structures) representing discrete-time LTI systems. They are not only useful in theoretical analysis, but can also be used to derive alternative structures for a transfer function starting from a known structure. The chapter considers systems with possibly multiple inputs and outputs (MIMO systems); systems with a single input and a single output (SISO systems) are special cases. General expressions for the transfer matrix and impulse response matrix are derived in terms of state-space descriptions. The concept of structure minimality is discussed, and related to properties called reachability and observability. It is seen that state-space descriptions give a different perspective on system poles, in terms of the eigenvalues of the state transition matrix. The chapter also revisits IIR digital allpass filters and derives several equivalent structures for them using so-called similarity transformations on state-space descriptions. Specifically, a number of lattice structures are presented for allpass filters. As a practical example of impact, if such a structure is used to implement the second-order allpass filter in a notch filter, then the notch frequency and notch quality can be independently controlled by two separate multipliers.
A number of properties relating to the inverse z-transform are discussed. The partial fraction expansion (PFE) of a rational z-transform plays a role in finding the inverse transform. It is shown that the inverse z-transform solution is not unique and depends on the region of convergence (ROC). Depending on the ROC, the solution may be causal, anticausal, two-sided, stable, or unstable. The condition for existence of a stable inverse transform is also developed. The interplay between causality, stability, and the ROC is established and illustrated with examples. The case of multiple poles is also considered. The theory and implementation of IIR linear-phase filters is discussed in detail. The connection between z-transform theory and analytic functions in complex variable theory is placed in evidence. Based on this connection, many intriguing examples of z-transform pairs are pointed out. In particular, closed-form expressions for radii of convergence of the z-transform can be obtained from complex variable theory. The case of unrealizable digital filters and their connection to complex variable theory is also discussed.
Thermodynamics is the science that governs most of the basic, or ‘static’, properties of a system such as a gas. In this chapter we will be focusing on thermodynamics of the dry atmosphere. Water vapour is sufficiently important to deserve a separate chapter. A thermodynamic system is characterised by a small number of state variables, primarily density, pressure, and temperature. After defining these, we will see how they vary as we move up through the atmosphere. Two key equations – the hydrostatic equation and the ideal gas equation – interconnect these variables and their profiles. The First Law of Thermodynamics tells us how the atmosphere responds to an input of heat, as well as a change in pressure, which may come about with elevation (vertical motion). This is the key to the atmosphere’s vertical stability, and (ultimately) to cloud formation.