Polar communications: Status and recommendations. Report of the Science Working Group

The capabilities of the existing communication links within the polar regions, as well as between the polar regions and the continental United States, are summarized. These capabilities are placed in the context of the principal scientific disciplines that are active in polar research, and in the context of how scientists both utilize and are limited by present technologies. Based on an assessment of the scientific objectives potentially achievable with improved communication capabilities, a list of requirements on and recommendations for communication capabilities necessary to support polar science over the next ten years is given

On non-normality and classification of amplification mechanisms in stability and resolvent analysis

We seek to quantify non-normality of the most amplified resolvent modes and predict their features based on the characteristics of the base or mean velocity profile. A 2-by-2 model linear Navier-Stokes (LNS) operator illustrates how non-normality from mean shear distributes perturbation energy in different velocity components of the forcing and response modes. The inverse of their inner product, which is unity for a purely normal mechanism, is proposed as a measure to quantify non-normality. In flows where there is downstream spatial dependence of the base/mean, mean flow advection separates the spatial support of forcing and response modes which impacts the inner product. Success of mean stability analysis depends on the normality of amplification. If the amplification is normal, the resolvent operator written in its dyadic representation reveals that the adjoint and forward stability modes are proportional to the forcing and response resolvent modes. If the amplification is non-normal, then resolvent analysis is required to understand the origin of observed flow structures. Eigenspectra and pseudospectra are used to characterize these phenomena. Two test cases are studied: low Reynolds number cylinder flow and turbulent channel flow. The first deals mainly with normal mechanisms and quantification of non-normality using the inverse inner product of the leading forcing and response modes agrees well with the product of the resolvent norm and distance between the imaginary axis and least stable eigenvalue. In turbulent channel flow, structures result from both normal and non-normal mechanisms. Mean shear is exploited most efficiently by stationary disturbances while bounds on the pseudospectra illustrate how non-normality is responsible for the most amplified disturbances at spatial wavenumbers and temporal frequencies corresponding to well-known turbulent structures

The Continued Relevance of the Irrelevance-of-Motive Maxim

The irrelevance-of-motive maxim-the longstanding principle that a defendant\u27s motives are irrelevant to criminal liability-has come under attack. Critics of this maxim claim that motives, under any plausible conception of the term, are in fact relevant in the criminal law. According to these critics, the only way to defend the truth of the irrelevance-of-motive maxim is to render it true by definition, by defining motive as the subcategory of intentions that are irrelevant to criminal liability. This Note defends the irrelevance-of-motive maxim by applying a plausible conception of motive that conforms to the historical meaning of the term. With the proper definition in place, the irrelevance-of-motive maxim can be understood as stating a valid principle of criminal law, defied only by the advent of a certain kind of bias crime legislation

A 50-year review of psychological reactance theory: Do not read this article

Psychological reactance theory (PRT; Brehm, 1966) posits that when something threatens or eliminates people’s freedom of behavior, they experience psychological reactance, a motivational state that drives freedom restoration. Complementing recent, discipline-specific reviews (e.g., Quick, Shen, & Dillard, 2013; Steindl, Jonas, Sittenthaler, Traut-Mattausch, & Greenberg, 2015), the current analysis integrates PRT research across fields in which it has flourished: social psychology and clinical psychology, as well as communication research. Moreover, the current review offers a rare synthesis of existing reactance measures. We outline five overlapping waves in the PRT literature: Wave 1: Theory proposal and testing, Wave 2: Contributions from clinical psychology, Wave 3: Contributions from communication research, Wave 4: Measurement of reactance, and Wave 5: Return to motivation. As part of our description of Wave 5, we detail scholars’ renewed focus on motivational aspects of the framework, and the ways in which this return to PRT’s motivational roots is allowing researchers to push its accuracy and applicability forward. We use this research that is already occurring in Wave 5 to outline three specific ways in which scholars can direct the continued application of motivation science to the advancement of PRT. Finally, as we outline in a future directions sections for each Wave, assimilating this research illustrates the ways in which an emphasis on motivation can expand and explain PRT research in communication, clinical psychology, and measurement

Field Effect Transistor Nanosensor for Breast Cancer Diagnostics

Silicon nanochannel field effect transistor (FET) biosensors are one of the most promising technologies in the development of highly sensitive and label-free analyte detection for cancer diagnostics. With their exceptional electrical properties and small dimensions, silicon nanochannels are ideally suited for extraordinarily high sensitivity. In fact, the high surface-to-volume ratios of these systems make single molecule detection possible. Further, FET biosensors offer the benefits of high speed, low cost, and high yield manufacturing, without sacrificing the sensitivity typical for traditional optical methods in diagnostics. Top down manufacturing methods leverage advantages in Complementary Metal Oxide Semiconductor (CMOS) technologies, making richly multiplexed sensor arrays a reality. Here, we discuss the fabrication and use of silicon nanochannel FET devices as biosensors for breast cancer diagnosis and monitoring

Contribution of Matrix Metalloproteinase-9 to Cerebral Edema and Functional Outcome following Experimental Subarachnoid Hemorrhage

Background: Cerebral edema is an important risk factor for death and poor outcome following subarachnoid hemorrhage (SAH). However, underlying mechanisms are still poorly understood. Matrix metalloproteinase (MMP)-9 is held responsible for the degradation of microvascular basal lamina proteins leading to blood-brain barrier dysfunction and, thus, formation of vasogenic cerebral edema. The current study was conducted to clarify the role of MMP-9 for the development of cerebral edema and for functional outcome after SAH. Methods: SAH was induced in FVB/N wild-type (WT) or MMP-9 knockout (MMP-9(-/-)) mice by endovascular puncture. Intracranial pressure (ICP), regional cerebral blood flow (rCBF), and mean arterial blood pressure (MABP) were continuously monitored up to 30 min after SAH. Mortality was quantified for 7 days after SAH. In an additional series neurological function and body weight were assessed for 3 days after SAH. Subsequently, ICP and brain water content were quantified. Results: Acute ICP, rCBF, and MABP did not differ between WT and MMP-9(-/-) mice, while 7 days' mortality was lower in MMP-9(-/-) mice (p = 0.03; 20 vs. 60%). MMP-9(-/-) mice also exhibited better neurological recovery, less brain edema formation, and lower chronic ICP. Conclusions: The results of the current study suggest that MMP-9 contributes to the development of early brain damage after SAH by promoting cerebral edema formation. Hence, MMP-9 may represent a novel molecular target for the treatment of SAH. Copyright (C) 2011 S. Karger AG, Base