Order and Disorder

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Effect of the Order Disorder Transition of the bcc Structure on the Solubility of Be in the Fe Be Binary System

Effect of the Order Disorder Transition of the bcc Structure on the Solubility of Be in the Fe Be Binary System

denoted by the square symbols in Fig. 1. For comparison, the values obtained by the present assessment are drawn using the solid lines for the ordered state (BCC B2) and the disordered state (BCC A2), respectively. The convex curva- ture of the free energy in the vicinity of the equiatomic composition corresponds to the formation of the B2 structure. The calculated results of the Fe-Be phase diagram are compared with the experimental data 1,3,4,20,21,23,28,29) in Fig. 2. The shaded area shown in Fig. 2 is the metastable (bcc+B2) two-phase region, which is accompanied by the ordering of the bcc structure on formation. The dotted line shows the order-disorder transition line, along which the two-phase field expands into the higher temperature range.

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Crossover between a displacive and an order-disorder phase transition

Crossover between a displacive and an order-disorder phase transition

One of the basic classification schemes for structural phase transitions consists in assigning it to the order-disorder or the displacive type. The displacive transition can be described as a freezing of a phonon mode, which shows ”critical softening” at the phase transition point. The occurrence of a soft mode is often used as criterion for a displacive transition in a real systems, since the frequency of the phonon modes is accessible by spectroscopic experiments.

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Order-disorder morphologies in rapidly solidified ε/ε′-Ni₅Ge₃ intermetallic

Order-disorder morphologies in rapidly solidified ε/ε′-Ni₅Ge₃ intermetallic

this would be expected to undergo a disorder-order transformation in the solid-state around 485 °C, but that cooling rates in excess of 700 K s -1 can partially suppress ordering, resulting in the partially ordered structures shown in Figure 2a-b. At these cooling rates the transformation to ' is also suppressed, resulting in retained, metastable  at room temperature. For cooling rates below 700 K s -1 it appears that the transformation to the low temperature '-phase is not suppressed, although this may be forced to occur via the congruent   ' transition, rather than via the   ' +  eutectoid reaction.

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Consciousness as the cosmic ordering principle and the interplay of order and disorder in the physical and biological systems

Consciousness as the cosmic ordering principle and the interplay of order and disorder in the physical and biological systems

Right from Big-Bang to the formation of living planets with macromolecules providing the basic building blocks for life to thrive, some ordering agency appears to have been at work against the principle of increase of disorder of the second law. From macromolecules to the evolution of living systems and for the continuous evolution of species thereafter, there is the need for an underlying ordering principle that has acted all through against the principle of increase of disorder till now and will also continue to act in future. Living systems are inevitably associated with an astounding amount of order and organization, although disorder in the form of fluctuation, noise and chaos also plays a crucial role in their systematic dynamics 11-12 .

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Order by quenched disorder in the model triangular antiferromagnet RbFe(MoO4)2

Order by quenched disorder in the model triangular antiferromagnet RbFe(MoO4)2

ear up-up-down structure, stabilized by fluctuations, to a fan structure supported by a weak static disorder, as well as a transformation of the lower-field spin structure from the Y type to an inverted Y structure. Our experiments establish the fluctuation origin of the 1 = 3 -plateau and the Y-type phases and show that the ground state selection process is affected by a strong competition between structural dis- order and thermal fluctuations. The structural disorder is found to lead to a positive biquadratic exchange. We observe a fundamentally different behavior between pure and lightly doped samples on heating, which results in the restoration of the magnetization plateau in the doped materials, while in a pure crystal the plateau is removed. These observations provide convincing confirmation of the competition between thermal and quenched disorder, dem- onstrating that the negative biquadratic term arising from thermal fluctuations once again dominates at a higher temperature. Disorder-induced modifications of the mag- netic structure may also be used to control multiferroicity of TLAFs and, perhaps, of other spiral antiferromagnets.

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Morphology of order-disorder structures in rapidly solidified L12 intermetallics

Morphology of order-disorder structures in rapidly solidified L12 intermetallics

system has previously been studied by Ahmed et al. [22] who, using a flux under- cooling technique, observed a maximum undercooling of 362 K, wherein the cor- responding growth velocity was measured at 3.55 m s -1 . In common with other re- searchers who have determined the velocity-undercooling curves for intermetallic compounds passing through the order-disorder transformation, Ahmed et al. ob- served a discontinuous break in the curve at the onset of fully disordered growth. This condition was observed for -Ni 3 Ge at an undercooling of 168 K and at a

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From Disorder to Order

From Disorder to Order

In the physical and social sciences, and especially in physics and economics, respectively, order and disorder (alternatively, equilibrium and disequilibrium in economics) refer to the presence or absence of some symmetry or correlation in a many-particle system. It follows that it is impor- tant to examine whether there is any regularity hidden in the phase transition of the disorder- order relationship. In this paper a series of experiments are devised and executed to reveal the power law relationship between order and disorder, and to determine that the power law is in- deed an important regular pattern in the phase transition from disorder to order.

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Order Disorder Transformation in Fe50Co50 Particles Synthesized by Polyol Process

Order Disorder Transformation in Fe50Co50 Particles Synthesized by Polyol Process

the other hand, to determine directly the long range order parameter S from the intensity of diffraction, so-called ‘‘superlattice line’’ is useful to investigate the thermal order- disorder transformation behavior in the alloy system. For bulk Fe-Co alloys, although such structural analysis ap- proached using neutron 14) or electron diffraction 15) have been

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Between Social Order and Disorder: The Destructive Mode of Coordination

Between Social Order and Disorder: The Destructive Mode of Coordination

To understand different sources of contradictory orders, one should remember that the monopoly of violence by the state is a new phenomenon, but even today the state has no monopoly over all the coercive means especially the moral means of coercion. We speak of ‘state’ law, i.e. of law guaranteed by the state, only when legal coercion is exercised through physical means of coercion of the political community. Wherever the means of coercion which provide the guarantee for a ‘right’ belong to some other authority such as a hierocracy, then one can speak of ‘extra-state law’. Moreover, the importance of coercive means in external enforcement notwithstanding, non violent means of destructive power such as exclusion from an organization or a community, a boycott, or the promise of reward and punishment in the next world may be under certain conditions much more efficient in producing compliance than a political apparatus whose coercive functioning is not always predictable. In such circumstances, individuals and social groups may follow other orders than what is officially promulgated by the state law. The most acute forms of ‘extra-state law’ are those related to a sovereignty crisis or a dual power situation that has usually been observed during revolution, war, and military occupation where the clash of contradictory orders may be so intense that disorder and anarchy ensue. But there are other more or less stable forms of coexistence between different types of authority that can lead to an intermediate state between social order and disorder with parallel institutions. The mode of coordination in such intermediate state is destructive, since extra legal or direct coercion paradoxically plays a key role in controlling and integrating parallel institutions. It should be particularly emphasised that only contradictory orders that weaken or undermine the state monopoly over physical means of coercion come within the scope of destructive coordination, since in such cases conflict resolution between parallel institutions relies upon extra legal coercive means or the balance of power. Other types of contradictory orders may not necessarily require the intervention of non-institutionalised coercion and can be explicated as specific constellations of the three known coordinating mechanisms, namely market, bureaucratic and ethical (reciprocity).

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Quantum order by disorder near criticality and the secret of partial order in MnSi

Quantum order by disorder near criticality and the secret of partial order in MnSi

Formulation of these ideas in the form of quantum order by disorder [14] (or Coleman-Weinberg) provides an at- tractive physical interpretation. Moreover, it guides one to a simple route through the calculations. The central idea is that certain deformations of the Fermi surface enhance the phase space available for low-energy quantum fluctuations and so self-consistently lower the free energy. This mecha- nism is familiar in condensed matter [15]. Unusually, here it is driven by fermionic rather than bosonic fluctuations. The framework suggests direct connections to various experimental probes. Fermi-surface deformations and re- constructions associated with the onset of the competing order can be observed in photoemission, and, recently, the measurement of entropic landscapes has proven a revealing probe of phase reconstruction near quantum critical points [12].

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THE CRIME AND DISORDER ACT GUIDANCE DOCUMENT: REPARATION ORDER

THE CRIME AND DISORDER ACT GUIDANCE DOCUMENT: REPARATION ORDER

provisions, it does not differ substantially from earlier versions. The guidance will be reissued in due course, together with that for the action plan order, parenting order and child safety order, as part of the series of formal guidance documents on the Crime and Disorder Act 1998. This will enable us to take account of any further feedback received by the end of June 2000 on the guidance and its usefulness, which can be sent to Jackie Hart, Juvenile Offenders Unit, Room 310, Home Office, 50 Queen Anne’s Gate, London SW1H 9AT. It will also enable us to take into account the current Powers of Criminal Courts (Sentencing) Bill, which will consolidate the sentencing powers of the courts.

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Order-disorder transition in the Chialvo-Bak `minibrain' controlled by network geometry

Order-disorder transition in the Chialvo-Bak `minibrain' controlled by network geometry

Assuming large, fixed η IP and η OP , the higher-order terms in Equation (5) will vanish for ζ > 1, and so P Γ will scale approximately according to a power law of ζ , with exponent − 1. Conversely, if ζ < 1 then the higher-order terms are brought back into play and P Γ scales approximately exponentially; Fig. 5 shows nicely how the critical point ζ = 1 acts as a transition point between these two scalings. The phase transition can thus be seen as a transi- tion between a high-interference phase where learned patterns are frequently destroyed by accident as a result of mistakes elsewhere, and a low-interference phase where active connections remain largely stable.

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Order and disorder in everyday action: the roles of contention scheduling and supervisory attention

Order and disorder in everyday action: the roles of contention scheduling and supervisory attention

The object and resource representation networks interact with the schema network via feedback loops, such that object and resource representation nodes excite, and are excited by, schema nodes, provided that the corresponding objects/resources are appropriate for the corresponding schemas. This mechanism ensures that, when a schema becomes active, it will tend to excite appropriate object and resource representations on which to operate, and when an object or resource representation becomes active, it will tend to excite schemas that use it. A selection process monitors the schema network and selects a schema when its activation exceeds its selection threshold. In order for the model to select schemas in an appropriate order, it is necessary that schemas be activated or triggered in sequence. Some low-level actions may be sequenced largely on the basis of environmental triggering. Higher order schemas (e.g., relating to making instant coffee, where most people add coffee grinds before milk/cream), however, require an additional mechanism to control sequence. This is achieved within the model by gating activation from a selected schema to its component schemas, such that only those component schemas that are appropriate at a given point in time, are activated when their parent schema is selected. In the coffee making case, excitation from the “coffee-making” schema would not pass to the “add milk” schema until the “add coffee grinds” schema was complete. This was originally achieved in a version of the model applied to the task of coffee preparation (Cooper & Shallice, 2000) through the specification of ad hoc ordering constraints within higher-level schemas, but a subsequent implementation applied to the more complex everyday task of preparing and packing a lunch box (Cooper et al., submitted) introduced pre-conditions and post-conditions on the components of all schemas. A portion of the schema hierarchy for this more complex task, with pre-conditions and post-conditions specified, is shown in figure 2.

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Order and disorder in Europe: Parliamentary agents and Royalist thugs 1649-1650

Order and disorder in Europe: Parliamentary agents and Royalist thugs 1649-1650

The employment of envoys and agents was by no means a development of the Civil Wars, but aside from Walter Strickland, parliament only developed anything approaching a coherent network of agents in early  , when £  ,  was voted for agents to provide ‘ letters of information ’. Their function, less diplomatic than intelligence gathering, meant that those best placed to undertake such work were men like Henry Parker, secretary to the Merchant Adventurers at Hamburg. Parker, parliament’s most important political pamphleteer of the  s, had left England in late  , having fallen foul of the factional wrangling within Westminster. He was ideal for the new role, since what was required was not merely intelligence from politically astute men like himself, but polished prose for parliament’s newspapers. Parliament had, by the late  s, developed a network of both intelligencers and news writers, who were brought together by men in Westminster like John Thurloe.$$ Parker’s name was singled out in the Commons’ resolution of January  , and Strickland was requested to ‘ take order with Mr Parker at Hamburg … to give us from time to time constant advertisements of what that king [of Denmark] treats or does ’.$% In early  the council of state told Parker of their ‘ being very glad you are where, by reason of your employment for the company, you have an opportunity of informing yourself, without suspicion, of what is in design, to the prejudice of this commonwealth ’.$& Parker’s presence, known to the royalists, would have been annoying not simply because of the intelligence-gathering implications. His position with the Merchant Adven- turers meant the existence of a rebel voice within a community whose support

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The effect of volume changes on the order disorder transition in substitutional alloys

The effect of volume changes on the order disorder transition in substitutional alloys

r 10 In a completely ordered alloy, however, should theor­ etically vanish and in fact extrapolation to the absolute zero shows that the residual resistance of an ordered alloy is much smaller than that of the disordered alloy. This would account for the pronounced minima in Figure 5. We have still, however, to consider a possible dependence of ^ on the state of order of the alloy. Detailed calcul­ ation shows that depends on the density of states and on the Debye characteristic temperature both of which may be expected to vary with the state of order of the alloy.

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Comorbidity between panic-disorder and bipolar disorder

Comorbidity between panic-disorder and bipolar disorder

major depression was the most common comorbid dis- order in a large sample of patients with AD; however, bipolar II disorder was widely associated with SoP, OCD and PD. The relative neglect in clinical and epidemio- logical research for the BPD spectrum disorders and AD is especially due to under-diagnosis of bipolar II disorders (often misdiagnosed as unipolar or personality disorders) in patients with AD. It has been documented that current official diagnostic systems grossly underestimate bipolar II and related disorders, and that clinicians specifically trained in bipolar II outperformed routine interviewers in structured interviews such as the SADS or SCID  40 . Al-

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Association of restless legs syndrome and mortality in end-stage renal disease: an analysis of the United States Renal Data System (USRDS)

Association of restless legs syndrome and mortality in end-stage renal disease: an analysis of the United States Renal Data System (USRDS)

We found a significantly higher proportion of patients with RLS had major depressive disorder, dysthymic dis- order, anxiety, depression or minor depressive disorder, as compared to those with no sleep disorder. This may have been related to changes in quality of life in those with RLS. Further, our results did not show increased mortality in patients with RLS as compared to those with no sleep disorders. These findings are similar to Stefanidis et al. who reported no difference in 3-year mortality in 579 hemodialysis patients with and without RLS [33] but are in contrast to other studies which have reported higher mortality in patients with RLS [12, 34]. ESRD studies claiming greater likelihood of mortality for patients with sleep disorders appear to contain relatively homogeneous populations in their analyses. Our study, however, leverages the USRDS which has collected data on ESRD patients undergoing dialysis from across the United States and boasts a very diverse population. In addition, we have used diagnostic codes to assess RLS prevalence and comorbidities, along with cause-of-death reports to determine survival status. The greater hetero- geneity in our patient population most likely drives im- portant differences in results between the studies.

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We investigated retrospectively  persons with autistic disorder from the Republic of Macedonia. Infantile autistic dis- order was diagnosed by DSM-IV and ICD- criteria. Plasma immunoglobulin classes (IgM, IgA, and IgG) and subclass- es (IgG, IgG, IgG, and IgG) were determined using Nephelometer Analyzer BN-. Th e most important fi ndings were found for multiple comparisons for the IgA variable between three pairs: male autistic from the fathers, female autistic from the mothers, as well as healthy sisters from the fathers. We also found statistically signifi cant diff erences be- tween three groups regarding autistic disorder (person with autistic disorder, father/mother of a person with autistic dis- order, and brother/sister) independent of sex belongs to IgA, IgG, and IgG variables. Multiple comparisons for the IgA variable also have shown statistically signifi cant diff erences between children with autistic disorder from the fathers and mothers, and healthy brothers and sisters from the fathers and mothers. In the conclusion, we could say that comparison between healthy children and children with autistic disorder from the same family should be tested for immunoglobulin classes and subclasses, because these children are from the similar generations.

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