Neuroinflammation is a putative target for the prevention and treatment of perioperative neurocognitive disorders.

IntroductionThe demographics of aging of the surgical population has increased the risk for perioperative neurocognitive disorders in which trauma-induced neuroinflammation plays a pivotal role.Sources of dataAfter determining the scope of the review, the authors used PubMed with select phrases encompassing the words in the scope. Both preclinical and clinical reports were considered.Areas of agreementNeuroinflammation is a sine qua non for development of perioperative neurocognitive disorders.Areas of controversyWhat is the best method for ameliorating trauma-induced neuroinflammation while preserving inflammation-based wound healing.Growing pointsThis review considers how to prepare for and manage the vulnerable elderly surgical patient through the entire spectrum, from preoperative assessment to postoperative period.Areas timely for developing researchWhat are the most effective and safest interventions for preventing and/or reversing Perioperative Neurocognitive Disorders

Electron spin decoherence of single Nitrogen-Vacancy defects in diamond

We present a theoretical analysis of the electron spin decoherence in single Nitrogen-Vacancy defects in ultra-pure diamond. The electron spin decoherence is due to the interactions with Carbon-13 nuclear spins in the diamond lattice. Our approach takes advantage of the low concentration (1.1%) of Carbon-13 and their random distribution in the diamond lattice by an algorithmic aggregation of spins into small, strongly interacting groups. By making use of this \emph{disjoint cluster} approach, we demonstrate a possibility of non-trival dynamics of the electron spin that can not be described by a single time constant. This dependance is caused by a strong coupling between the electron and few nuclei and results, in particular, in a substantial echo signal even at microsecond time scales. Our results are in good agreement with recent experimental observations

Defining Agency and Its Scope (II)

Fiduciary law necessarily raises issues of delineation and demarcation, which this paper demonstrates through examples involving common-law agents. Serving as an agent, and thus as a fiduciary, does not necessarily mean that agency law prescribes all duties that the agent owes the principal. The agent may have rights external to the relationship that the agent may exercise, distinct from the duty of loyalty owed the principal. When an agent acts outside the bounds of an agency relationship, the principal’s consent is not requisite to conduct that would constitute disloyalty within the bounds of the agency relationship. The paper illustrates the significance of this point through a series of examples drawn from a range of contexts, including auctions of art objects. Prior scholarship neglects the implications of demarcations that define the scope of an agency relationship and of fiduciary relationships more generically. More generally or theoretically, the paper examines the qualities of fiduciary duty as a default rule, arguing that the relative “stickiness” of the default varies. Agency law contains two different kinds of altering rules—necessary and sufficient conditions to vary a default rule—consisting of agreements that define the scope of the agent’s representative role on behalf of the principal, and consent by the principal to actions by the agent within that scope that relieve the agent of liability for breach of fiduciary duty, which impose significantly different requisites. The basic distinction between agreement and consent has parallels elsewhere in agency law; for example, ratification, like consent, requires specificity because to be legally effective ratification requires that the principal know, as a matter of historical fact, what the agent has done. Agreement, on the other hand, requires less specificity, comparable to manifestations that confer actual authority on an agent which necessarily does not require that the principal foresee all actions that the agent may take that fall within the scope of the grant of authority. And ratification, like effective consent, is a matter of historical fact, not hypothesis. These implications follow because agency law, by positioning an agent as the principal’s representative for purposes of legally-salient interactions with third parties and facts about the world, frames the agent as an extension of the principal, not the principal’s substitute

Coherent Population Trapping with a controlled dissipation: applications in optical metrology

We analyze the properties of a pulsed Coherent Population Trapping protocol that uses a controlled decay from the excited state in a $\Lambda$-level scheme. We study this problem analytically and numerically and find regimes where narrow transmission, absorption, or fluorescence spectral lines occur. We then look for optimal frequency measurements using these spectral features by computing the Allan deviation in the presence of ground state decoherence and show that the protocol is on a par with Ramsey-CPT. We discuss possible implementations with ensembles of alkali atoms and single ions and demonstrate that typical pulsed-CPT experiments that are realized on femto-second time-scales can be implemented on micro-seconds time-scales using this scheme.Comment: 9 pages, 7 figure

Validation and implication of segmentation on Empirical Bayes for highway safety studies

Typically, crash frequency is modelled as Poison where the variation is the square root of the expected number. If the expected number of crashes is small, the variation is a large percentage of the expected number of crashes, and the observed number of crashes provides a crude estimate for the expected number. A better estimate is obtained when the expected number is large. For a specific location, there are two approaches for performing measurements where the expected number of crashes is large. One approach is to measure over a long period of time. However, data are not often available for long periods. Even if available, changes in conditions over time, such as increase in traffic volumes or improvement in infrastructure, may limit the useful time frame. Another approach is to perform measurements over a large number of similar locations, providing a relatively precise estimate for the distribution. Then, one can use the Empirical Bayes (EB) approach to combine the relatively precise estimate for the distribution with the less precise estimate for the expected number at the location of interest, resulting is an improved estimate for the expected number at that location. This paper explores the two approaches. It uses multiple years of data from the Highway Safety Information System for California intersections and highway links from the State of Iowa. Data from a single year is used to estimate the expected number of crashes at locations, following the EB approach. Data from multiple years at each location is then used to estimate the expected number of crashes at those locations, and the results from the two approaches are compared. No such large scale validation has yet been performed. The effect of a priori segmentation of the highway system is also explored. Longer, homogeneous sections are found both to improve the statistical validity of models and to improve the EB correction of one-year section crash estimates