Hydrodynamic Irreversibility in Particle Suspensions with Non-Uniform Strain

A dynamical phase transition from reversible to irreversible behavior occurs when particle suspensions are subjected to uniform oscillatory shear, even in the Stokes flow limit. We consider a more general situation with non-uniform strain (e.g. oscillatory channel flow), which is observed to exhibit markedly different dynamics. Self-organization and shear-induced migration only partially explain the delayed, simultaneous onset of irreversibility across the channel. The onset of irreversibility is accompanied by long-range correlated particle motion. This motion leads to particle activity even at the channel center, where the strain is negligible, and prevents the system from evolving into a reversible state

Prison Research from the Inside: The Role of Convict Autoethnography

A perspective that has often been absent in criminal justice research is that of former prisoners. This article discusses the establishment, in 1997, of “convict criminology,” a group of scholars producing research informed by their experiences of crime and the criminal justice process; that is, either those who have served time themselves or who have operated alongside prisoners as professionals in custodial settings. It is argued that such scholars face similar dilemmas to others in terms of emotionalism, but suggests that their emotions are of a different nature. While an “insider” perspective cannot lay claim to scientific “objectivity,” the article argues that the existence of emotion does not invalidate an “insider” criminologist’s views. Rather, the passion engendered by the experience of incarceration can add color, context, and contour to data collection, findings, and analysis and may therefore be regarded as an essential thread in the tapestry of criminological inquiry

Exploring the Origin of Solar Energetic Electrons I: Constraining the Properties of the Acceleration Region Plasma Environment

Solar flare electron acceleration is an efficient process, but its properties (mechanism, location) are not well constrained. Via hard X-ray (HXR) emission, we routinely observe energetic electrons at the Sun, and sometimes we detect energetic electrons in interplanetary space. We examine if the plasma properties of an acceleration region (size, temperature, density) can be constrained from in-situ observations, helping to locate the acceleration region in the corona, and infer the relationship between electrons observed in-situ and at the Sun. We model the transport of energetic electrons, accounting for collisional and non-collisional effects, from the corona into the heliosphere (to 1.0 AU). In the corona, electrons are transported through a hot, over-dense region. We test if the properties of this region can be extracted from electron spectra (fluence and peak flux) at different heliospheric locations. We find that cold, dense coronal regions significantly reduce the energy at which we see the peak flux and fluence for distributions measured out to 1.0 AU, the degree of which correlates with the temperature and density of plasma in the region. Where instrument energy resolution is insufficient to differentiate the corresponding peak values, the spectral ratio of [7-10) to [4-7) keV can be more readily identified and demonstrates the same relationship. If flare electrons detected in-situ are produced in, and/or transported through hot, over-dense regions close to HXR-emitting electrons, then this plasma signature should be present in their lower-energy spectra (1-20 keV), observable at varying heliospheric distances with missions such as Solar Orbiter.Comment: 16 pages, 8 figure

A Fiber Optic RF Resonant Cavity Sensor for Strain Sensing-Forrcs

A fiber optic vibration and strain sensor described by Rogowski et al [1] implemented a radio frequency (rf) phase locked loop in an optical strain gauge bonded to or embedded in a composite structure. A laser is modulated at radio frequency by a voltage controlled oscillator. The phase delay through the optical fiber transmission line is compared to the source oscillator, and the resulting error signal shifts the oscillator, locking the phase. Strain in the specimen (a composite panel) produces a change in optical phase length in the fiber. Tracking the frequency change gives a measure of the integrated strain transduced into the fiber from the strained panel. Strain level sensitivity on the order of 0.1 microstrains has been reported [1]. However, considerable confusion surrounds the performance of the reported sensor, since noise presumed to arise from cladding/core mode interference and splice reflections makes significant filtering necessary, reducing the bandwidth of the sensor, e.g., increasing the response time to detect strains [2]. This limits vibration control applications

UHF Modulation and Fourier Transform Differential Time Domain Techniques for Measuring Strain Via Fiber Optics

The design and manufacture of future space transportation and delivery systems will be strongly driven by safety, cost, maintenance and reliability considerations. Advanced composite structural components are likely to be a key element in realizing these system objectives. Composites have the additional potential of enabling the embedment of sensors for system health monitoring, which supports requirements for low cost safety, maintenance and repair diagnosis

Development and application of an antibiotic spectrum index for benchmarking antibiotic selection patterns across hospitals

Standard metrics for antimicrobial use consider volume but not spectrum of antimicrobial prescribing. We developed an antibiotic spectrum index (ASI) to classify commonly used antibiotics based on activity against important pathogens. The application of this index to hospital antibiotic use reveals how this tool enhances current antimicrobial stewardship metrics.Infect Control Hosp Epidemiol 2017;38:993–997</jats:p

Phosphatidylinositol 3-kinase pathway genomic alterations in 60,991 diverse solid tumors informs targeted therapy opportunities.

BackgroundThe phosphatidylinositol 3-kinase (PI3K) pathway is frequently altered in cancer. This report describes the landscape of PI3K alterations in solid tumors as well as co-alterations serving as potential resistance/attenuation mechanisms.MethodsConsecutive samples were analyzed in a commercial Clinical Laboratory Improvement Amendment-certified laboratory using comprehensive genomic profiling performed by next-generation sequencing (315 genes). The co-alterations evaluated included the Erb-B2 receptor tyrosine kinase 2 (ERBB2), ERBB3, ERBB4, RAS, MET proto-oncogene tyrosine kinase (MET), and mitogen-activated protein kinase kinase (MAP2K) genes as well as tumor protein 53 (TP53), estrogen receptor 1 (ESR1), and androgen receptor (AR).ResultsAlterations in any of 18 PI3K-pathway associated genes were identified in 44% of 60,991 tumors. Although single base and insertions/deletions (indels) were the most frequent alterations, copy number changes and rearrangements were identified in 11% and 0.9% of patients, respectively. Overall, the most frequently altered genes were PIK3 catalytic subunit α (PIK3CA) (13%), phosphatase and tensin homolog (PTEN) (9%), and serine/threonine kinase 11 (STK11) (5%). Tumor types that frequently harbored at least 1 PI3K alteration were uterine (77%), cervical (62%), anal (59%), and breast (58%) cancers. Alterations also were discerned frequently in tumors with carcinosarcoma (89%) and squamous cell carcinoma (62%) histologies. Tumors with a greater likelihood of co-occurring PI3K pathway and MAPK pathway alterations included colorectal cancers (odds ratio [OR], 1.64; P &lt; .001), mesotheliomas (OR, 2.67; P = .024), anal cancers (OR, 1.98; P = .03), and nonsquamous head and neck cancers (OR, 2.03; P = .019). The co-occurrence of ESR1 and/or AR alterations with PI3K alterations was statistically significant in bladder, colorectal, uterine, prostate, and unknown primary cancers.ConclusionsComprehensive genomic profiling reveals altered PI3K-related genes in 44% of solid malignancies, including rare disease and histology types. The frequency of alterations and the co-occurrence of resistance pathways vary by tumor type, directly affecting opportunities for targeted therapy