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Fitbit®: An accurate and reliable device for wireless physical activity tracking
Although physicians recognize the importance of physical activity in the prevention and maintenance of chronic diseases, few incorporate physical activity counseling into routine clinic visits. One major barrier has been the paucity of means to objectively assess patient's long-term physical activity patterns. We investigated if the Fitbit®, one of the most common wireless physical activity trackers in the consumer market, met reasonable validity and reliability standards such that they could be used by primary care physicians to monitor their patient's physical activity objectively between clinic visits.
Keywords:
Physical activity; Validation; Activity monitoring; Accelerometer; Walking; Fitbi
Photonic mid-infrared nulling for exoplanet detection on a planar chalcogenide platform
The future of exoplanet detection lies in the mid-infrared (MIR). The MIR
region contains the blackbody peak of both hot and habitable zone exoplanets,
making the contrast between starlight and planet light less extreme. It is also
the region where prominent chemical signatures indicative of life exist, such
as ozone at 9.7 microns. At a wavelength of 4 microns the difference in
emission between an Earth-like planet and a star like our own is 80 dB. However
a jovian planet, at the same separation exhibits 60 dB of contrast, or only 20
dB if it is hot due to its formation energy or being close to its host star. A
two dimensional nulling interferometer, made with chalcogenide glass, has been
measured to produce a null of 20 dB, limited by scattered light. Measures to
increase the null depth to the theoretical limit of 60 dB are discussed.Comment: Was published in SPIE: Optical and Infrared Interferometry and
Imaging VI, Mike Ireland presente
Chalcogenide glass planar MIR couplers for future chip based Bracewell interferometers
Photonic integrated circuits are established as the technique of choice for a
number of astronomical processing functions due to their compactness, high
level of integration, low losses, and stability. Temperature control,
mechanical vibration and acoustic noise become controllable for such a device
enabling much more complex processing than can realistically be considered with
bulk optics. To date the benefits have mainly been at wavelengths around 1550
nm but in the important Mid-Infrared region, standard photonic chips absorb
light strongly. Chalcogenide glasses are well known for their transparency to
beyond 10000 nm, and the first results from coupler devices intended for use in
an interferometric nuller for exoplanetary observation in the Mid-Infrared L
band (3800-4200 nm) are presented here showing that suitable performance can be
obtained both theoretically and experimentally for the first fabricated devices
operating at 4000 nm.Comment: in Proc. SPIE 9907, Optical and Infrared Interferometry and Imaging
V, 990730 (August 4, 2016
Protecting eyewitness evidence: Examining the efficacy of a self-administered interview tool
Given the crucial role of eyewitness evidence, statements should be obtained as soon as possible after an incident. This is not always achieved due to demands on police resources. Two studies trace the development of a new tool, the Self-Administered Interview (SAI), designed to elicit a comprehensive initial statement. In Study 1, SAI participants reported more correct details than participants who provided a free recall account, and performed at the same level as participants given a Cognitive Interview. In Study 2, participants viewed a simulated crime and half recorded their statement using the SAI. After a delay of 1 week, all participants completed a free recall test. SAI participants recalled more correct details in the delayed recall task than control participants
Impaired CD8 T cell memory and CD4 T cell primary responses in IL-7Rα mutant mice
Loss of interleukin (IL)-7 or the IL-7 receptor alpha (IL-7Rα, CD127) results in severe immunodeficiencies in mice and humans. To more precisely identify signals governing IL-7 function in vivo, we have disrupted the IL-7Rα Y449XXM motif in mice by knock-in mutagenesis (IL-7Rα449F). Thymic precursors were reduced in number in IL-7Rα449F mice, but in marked contrast to IL-7Rα−/− knockout mice, thymocytes and peripheral T cells developed normally. Strikingly, Listeria infection revealed that CD4 and CD8 T cells had different requirements for IL-7Rα signals. CD4 T cells failed to mount a primary response, but despite normal CD8 primary responses, maintenance of CD8 memory was impaired in IL-7Rα449F mice. Furthermore, we show that Bcl-2 is IL-7Rα Y449 independent and insufficient for IL-7–mediated maintenance of CD8 memory
Exceptional AGN-driven turbulence inhibits star formation in the 3C 326N radio galaxy
We detect bright [CII]158μm line emission from the radio galaxy 3C 326N at z=0.09, which shows weak star formation (SFR⊙~yr−1) despite having strong H2 line emission and 2×109M⊙ of molecular gas. The [CII] line is twice as strong as the 0-0S(1) 17μm H2 line, and both lines are much in excess what is expected from UV heating. We combine infrared Spitzer and Herschel data with gas and dust modeling to infer the gas physical conditions. The [CII] line traces 30 to 50% of the molecular gas mass, which is warm (70−3. The [CII] line is broad with a blue-shifted wing, and likely to be shaped by a combination of rotation, outflowing gas, and turbulence. It matches the near-infrared H2 and the Na D optical absorption lines. If the wing is interpreted as an outflow, the mass loss rate would be larger than 20M⊙/yr, and the depletion timescale shorter than the orbital timescale (108yr). These outflow rates may be over-estimated because the stochastic injection of turbulence on galactic scales can contribute to the skewness of the line profile and mimic outflowing gas. We argue that the dissipation of turbulence is the main heating process of this gas. Cosmic rays can also contribute to the heating but they require an average gas density larger than the observational constraints. We show that strong turbulent support maintains a high gas vertical scale height (0.3-4kpc) in the disk and can inhibit the formation of gravitationally-bound structures at all scales, offering a natural explanation for the weakness of star formation in 3C 326N. To conclude, the bright [CII] line indicates that strong AGN jet-driven turbulence may play a key role in enhancing the amount of molecular gas (positive feedback) but yet can prevent star formation on galactic scales (negative feedback)
Loss of lag-response curvilinearity of indices of heart rate variability in congestive heart failure
BACKGROUND: Heart rate variability (HRV) is known to be impaired in patients with congestive heart failure (CHF). Time-domain analysis of ECG signals traditionally relies heavily on linear indices of an essentially non-linear phenomenon. Poincaré plots are commonly used to study non-linear behavior of physiologic signals. Lagged Poincaré plots incorporate autocovariance information and analysis of Poincaré plots for various lags can provide interesting insights into the autonomic control of the heart. METHODS: Using Poincaré plot analysis, we assessed whether the relation of the lag between heart beats and HRV is altered in CHF. We studied the influence of lag on estimates of Poincaré plot indices for various lengths of beat sequence in a public domain data set (PhysioNet) of 29 subjects with CHF and 54 subjects with normal sinus rhythm. RESULTS: A curvilinear association was observed between lag and Poincaré plot indices (SD1, SD2, SDLD and SD1/SD2 ratio) in normal subjects even for a small sequence of 50 beats (p value for quadratic term 3 × 10(-5), 0.002, 3.5 × 10(-5 )and 0.0003, respectively). This curvilinearity was lost in patients with CHF even after exploring sequences up to 50,000 beats (p values for quadratic term > 0.5). CONCLUSION: Since lagged Poincaré plots incorporate autocovariance information, these analyses provide insights into the autonomic control of heart rate that is influenced by the non-linearity of the signal. The differences in lag-response in CHF patients and normal subjects exist even in the face of the treatment received by the CHF patients
Maximal Spontaneous Photon Emission and Energy Loss from Free Electrons
Free electron radiation such as Cerenkov, Smith--Purcell, and transition
radiation can be greatly affected by structured optical environments, as has
been demonstrated in a variety of polaritonic, photonic-crystal, and
metamaterial systems. However, the amount of radiation that can ultimately be
extracted from free electrons near an arbitrary material structure has remained
elusive. Here we derive a fundamental upper limit to the spontaneous photon
emission and energy loss of free electrons, regardless of geometry, which
illuminates the effects of material properties and electron velocities. We
obtain experimental evidence for our theory with quantitative measurements of
Smith--Purcell radiation. Our framework allows us to make two predictions. One
is a new regime of radiation operation---at subwavelength separations, slower
(nonrelativistic) electrons can achieve stronger radiation than fast
(relativistic) electrons. The second is a divergence of the emission
probability in the limit of lossless materials. We further reveal that such
divergences can be approached by coupling free electrons to photonic bound
states in the continuum (BICs). Our findings suggest that compact and efficient
free-electron radiation sources from microwaves to the soft X-ray regime may be
achievable without requiring ultrahigh accelerating voltages.Comment: 7 pages, 4 figure
A Transdisciplinary Approach to Eliminate Cancer Disparities: An Overview of Community Engagement and Outreach Efforts in an National Institute of Health Center for Excellence
Creating health equity and eliminating health disparities are considered national priorities for improving the health of Americans (U.S. Department of Health and Human Services, n.d.). Health disparities are a primary public health concern, yet are complex phenomena and challenging to research (Harper & Lynch, 2005). The National Institute on Minority Health and Health Disparities (NIMHD), under the National Institute of Health (NIH), is committed to finding solutions to achieve this goal through the creation of interdisciplinary Centers of Excellence. In 2009, the University of South Florida (USF) and Moffitt Cancer Center (Moffitt) received a NIMHD Exploratory Center of Excellence award to collaboratively create the Center for Equal Health (CEH). The Center for Equal Health investigates cancer health disparities, their origins, and potential solutions for the reduction and ultimate elimination of health inequities among racial/ethnic minorities and the medically underserved. Currently in its fourth year, the purpose of the center is to utilize a transdisciplinary approach (basic, clinical, and population sciences) to develop novel interventions and solutions for the reduction and elimination of cancer health disparities among minority and underserved communities in Florida through science, practice, and policy. Specifically, the center’s vision is to achieve health equity in the community through cancer research, education, and training. To fulfill this vision, CEH is organized into four cores: 1) Administration, 2) Research, 3) Research, Training, and Education, and 4) Community Engagement and Outreach. This paper specifically describes the community-based education and training initiatives, specifically the Community Health Worker training, talking circles, science tours, community research council, and podcasts/media outreach, of the Community Engagement and Outreach Core (CEOC). The processes of the activities of the CEOC and lessons learned are highlighted with the primary goal of sharing a successful model of community engagement
SOX2 regulates acinar cell development in the salivary gland
Acinar cells play an essential role in the secretory function of exocrine organs. Despite this requirement, how acinar cells are generated during organogenesis is unclear. Using the acini-ductal network of the developing human and murine salivary gland, we demonstrate an unexpected role for SOX2 and parasympathetic nerves in generating the acinar lineage that has broad implications for epithelial morphogenesis. Despite SOX2 being expressed by progenitors that give rise to both acinar and duct cells, genetic ablation of SOX2 results in a failure to establish acini but not ducts. Furthermore, we show that SOX2 targets acinar-specific genes and is essential for the survival of acinar but not ductal cells. Finally, we illustrate an unexpected and novel role for peripheral nerves in the creation of acini throughout development via regulation of SOX2. Thus, SOX2 is a master regulator of the acinar cell lineage essential to the establishment of a functional organ
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