Reduced and declining physical function in prevalent dialysis patients – identifying the vulnerable

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BOUNDING THE SMARANDACHE FUNCTION

The article illustrates the importance of being able to calculate the Smarandache function for prime powers. This paper will be considering that process

Biotechnological developments, socio-technical processes and materiality : the affordances and constraints of ‘social innovation'

Peer reviewedPreprin

Executive authority, the personal vote, and budget discipline in Latin American and Carribean countries

Recent scholarship on the impact of fiscal institutions on budgeting outcomes in Latin American and Caribbean (LAC) countries indicates that political institutions impact the level of budget discipline. BuiIding upon this previous research, we argue that the principle problem that must be addressed to insure strong fiscal discipline is the common pool resource (CPR) problem. The source of the problem, as well as its solution, differ in the government and in the legislature. At the cabinet level, the CPR problem arises because ministers consider the spending and tax implications of decisions on their ministries (only) instead of on the general population. As Hallerberg and von Hagen (1999) indicate, the appropriate solution at the cabinet level depends upon the coalition structure of the government. Given that all LAC countries have either presidential or oneparty parliamentary systems, a strong central player like the finance minister can reduce the CPR problem at the cabinet level. A similar strengthening of the executive vis-à-vis the legislature, in contrast, does not necessarily lead to tighter fiscal discipline. The level of the CPR problem in the legislature depends upon the type of electoral system. If states have open list proportional representation systems, then increases in district magnitude increase the problem, while under closed lists increases in district magnitude decrease the problem. Using a data set of LAC countries for the period 1988-97 and following Carey and Shugart (1995), we create an index for the incentives for the personal vote. We find that executive power in the budget process is most effective in reducing budget deficits when the personal vote is high in the legislature, while strengthening the president (or prime minister) in countries where the personal vote is low in the legislature has no statistically significant effect. This finding has practical implications for the design of fiscal institutions in LAC countries—granting the executive a privileged position vis-à-vis the legislature has beneficial effects on the budget balance only when the CPR problem in the legislature is large. Moreover, an alternative institutional change is to reform a country’s electoral system. The second option may be more feasible in countries where legislators are unlikely to give the president more power, or where dictatorial pasts make populations wary of granting the executive too much authority on any policy area. --

Physical implementations of quantum absorption refrigerators

Absorption refrigerators are autonomous thermal machines that harness the spontaneous flow of heat from a hot bath into the environment in order to perform cooling. Here we discuss quantum realizations of absorption refrigerators in two different settings: namely, cavity and circuit quantum electrodynamics. We first provide a unified description of these machines in terms of the concept of virtual temperature. Next, we describe the two different physical setups in detail and compare their properties and performance. We conclude with an outlook on future work and open questions in this field of research.Comment: Patrick P. Potts was formerly known as Patrick P. Hofe

Organizationally Sensible vs. Legal-Centric Approaches to Employment Decisions With Legal Implications

This article is intended to: 1) alert human resource (HR) professionals to the risk that they, and the managers they serve, are unnecessarily contributing to the impact of legal considerations on the management of employees as a result of “legal-centric decision making”; and 2) provide information and guidance that will assist HR professionals in promoting better informed, more organizationally sensible responses to employment issues that have potential legal implications. The “legal-centric decision making” construct is introduced and illustrated, a model of the primary factors contributing to legal-centric decision making is presented, and keys to avoiding legal-centric decision making are identified and discussed

Two-message quantum interactive proofs and the quantum separability problem

Suppose that a polynomial-time mixed-state quantum circuit, described as a sequence of local unitary interactions followed by a partial trace, generates a quantum state shared between two parties. One might then wonder, does this quantum circuit produce a state that is separable or entangled? Here, we give evidence that it is computationally hard to decide the answer to this question, even if one has access to the power of quantum computation. We begin by exhibiting a two-message quantum interactive proof system that can decide the answer to a promise version of the question. We then prove that the promise problem is hard for the class of promise problems with "quantum statistical zero knowledge" (QSZK) proof systems by demonstrating a polynomial-time Karp reduction from the QSZK-complete promise problem "quantum state distinguishability" to our quantum separability problem. By exploiting Knill's efficient encoding of a matrix description of a state into a description of a circuit to generate the state, we can show that our promise problem is NP-hard with respect to Cook reductions. Thus, the quantum separability problem (as phrased above) constitutes the first nontrivial promise problem decidable by a two-message quantum interactive proof system while being hard for both NP and QSZK. We also consider a variant of the problem, in which a given polynomial-time mixed-state quantum circuit accepts a quantum state as input, and the question is to decide if there is an input to this circuit which makes its output separable across some bipartite cut. We prove that this problem is a complete promise problem for the class QIP of problems decidable by quantum interactive proof systems. Finally, we show that a two-message quantum interactive proof system can also decide a multipartite generalization of the quantum separability problem.Comment: 34 pages, 6 figures; v2: technical improvements and new result for the multipartite quantum separability problem; v3: minor changes to address referee comments, accepted for presentation at the 2013 IEEE Conference on Computational Complexity; v4: changed problem names; v5: updated references and added a paragraph to the conclusion to connect with prior work on separability testin

Leggett-Garg inequalities and the geometry of the cut polytope

The Bell and Leggett-Garg tests offer operational ways to demonstrate that non-classical behavior manifests itself in quantum systems, and experimentalists have implemented these protocols to show that classical worldviews such as local realism and macrorealism are false, respectively. Previous theoretical research has exposed important connections between more general Bell inequalities and polyhedral combinatorics. We show here that general Leggett-Garg inequalities are closely related to the cut polytope of the complete graph, a geometric object well-studied in combinatorics. Building on that connection, we offer a family of Leggett-Garg inequalities that are not trivial combinations of the most basic Leggett-Garg inequalities. We then show that violations of macrorealism can occur in surprising ways, by giving an example of a quantum system that violates the new "pentagon" Leggett-Garg inequality but does not violate any of the basic "triangle" Leggett-Garg inequalities.Comment: 5 pages, 1 figur