Sample records for tangle toggle tackle

  1. Progression from Chronic Atrophic Gastritis to Gastric Cancer; Tangle, Toggle, Tackle with Korea Red Ginseng

    PubMed Central

    Kim, Yoon Jae; Chung, Jun Won; Lee, So Jung; Choi, Ki Seok; Kim, Ju Hyun; Hahm, Ki Baik

    2010-01-01

    Key molecular players that link inflammation to carcinogenesis are prostaglandins, cytokines, nuclear factor-κB (NF-κB), chemokines, angiogenic growth factors, and free radicals, all of which lead to increased mutations and altered functions of important enzymes and proteins, for example, activation of oncogenic products and/or inhibition of tumor suppressor proteins, in inflamed tissues, thus contributing to multi-stage carcinogenesis process. Interpreted reversely, the identification of the molecular mechanisms by which chronic inflammation increases cancer risk or optimal intervention of targeted drugs or agents during the inflammation-associated carcinogenic process could be a necessary basis for developing new strategy of cancer prevention at many sites. In this review, we discuss the possibilities for cancer prevention by controlling inflammation process in Helicobacter pylori (H. pylori)-associated inflamed stomach with Korea red ginseng. Korea red ginseng is a good example of a natural herb that has ubiquitous properties that are conductive to stop inflammatory carcinogenesis that is un wanted outcome of H. pylori infection, rendering rejuvenation of chronic atrophic gastritis. PMID:20490314

  2. Easy insert, easy release toggle bolt fastener

    NASA Technical Reports Server (NTRS)

    Kubokawa, C. C.

    1970-01-01

    Releasable pin-type toggle bolt fastener is constructed so that, when positioned in hole, toggle action prevents its removal and locknut anchors it firmly in place. Fastener is easily removed by loosening locknut and retraction of toggle wings.

  3. BINARY STORAGE ELEMENT

    DOEpatents

    Chu, J.C.

    1958-06-10

    A binary storage device is described comprising a toggle provided with associsted improved driver circuits adapted to produce reliable action of the toggle during clearing of the toggle to one of its two states. or transferring information into and out of the toggle. The invention resides in the development of a self-regulating driver circuit to minimize the fluctuation of the driving voltages for the toggle. The disclosed driver circuit produces two pulses in response to an input pulse: a first or ''clear'' pulse beginning nt substantially the same time but endlrg slightly sooner than the second or ''transfer'' output pulse.

  4. Two fault tolerant toggle-hook release

    NASA Technical Reports Server (NTRS)

    Graves, Thomas Joseph (Inventor); Brown, Christopher William (Inventor)

    1991-01-01

    A coupling device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body, each of which is attachable to a different one of a pair of structures to be joined. The fastener plate and body are coupled by an elongate toggle mounted at one end in a socket on the fastener plate for universal pivotal movement thereon. The other end of the toggle is received in an opening in the fastener body and adapted for limited pivotal movement therein. The toggle is adapted to be restrained by three latch hooks arranged in symmetrical equiangular spacing about the axis of the toggle, each hook being mounted on the fastener body for pivotal movement between an unlatching non-contact position with respect to the toggle and a latching position in engagement with a latching surface of the toggle. The device includes releasable lock means for locking each latch hook in its latching position whereby the toggle couples the fastener plate to the fastener body and means for releasing the lock means to unlock each said latch hook from the latch position whereby the unlocking of at least one of the latch hooks from its latching position results in the decoupling of the fastener plate from the fastener body.

  5. Force-time profile differences in the delivery of simulated toggle-recoil spinal manipulation by students, instructors, and field doctors of chiropractic.

    PubMed

    DeVocht, James W; Owens, Edward F; Gudavalli, Maruti Ram; Strazewski, John; Bhogal, Ramneek; Xia, Ting

    2013-01-01

    The objectives of this study were to examine the force-time profiles of toggle recoil using an instrumented simulator to objectively measure and evaluate students' skill to determine if they become quicker and use less force during the course of their training and to compare them to course instructors and to field doctors of chiropractic (DCs) who use this specific technique in their practices. A load cell was placed within a toggle recoil training device. The preload, speed, and magnitude of the toggle recoil thrusts were measured from 60 students, 2 instructors, and 77 DCs (ie, who use the toggle recoil technique in their regular practice). Student data were collected 3 times during their toggle course (after first exposure, at midterm, and at course end.) Thrusts showed a dual-peak force-time profile not previously described in other forms of spinal manipulation. There was a wide range of values for each quantity measured within and between all 3 subject groups. The median peak load for students decreased over the course of their class, but they became slower. Field doctors were faster than students or instructors and delivered higher peak loads. Toggle recoil thrusts into a dropping mechanism varied based upon subject and amount of time practicing the task. As students progressed through the class, speed reduced as they increased control to lower peak loads. In the group studies, field DCs applied higher forces and were faster than both students and instructors. There appears to be a unique 2-peak feature of the force-time plot that is unique to toggle recoil manipulation with a drop mechanism. Copyright © 2013 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  6. Automated design of genetic toggle switches with predetermined bistability.

    PubMed

    Chen, Shuobing; Zhang, Haoqian; Shi, Handuo; Ji, Weiyue; Feng, Jingchen; Gong, Yan; Yang, Zhenglin; Ouyang, Qi

    2012-07-20

    Synthetic biology aims to rationally construct biological devices with required functionalities. Methods that automate the design of genetic devices without post-hoc adjustment are therefore highly desired. Here we provide a method to predictably design genetic toggle switches with predetermined bistability. To accomplish this task, a biophysical model that links ribosome binding site (RBS) DNA sequence to toggle switch bistability was first developed by integrating a stochastic model with RBS design method. Then, to parametrize the model, a library of genetic toggle switch mutants was experimentally built, followed by establishing the equivalence between RBS DNA sequences and switch bistability. To test this equivalence, RBS nucleotide sequences for different specified bistabilities were in silico designed and experimentally verified. Results show that the deciphered equivalence is highly predictive for the toggle switch design with predetermined bistability. This method can be generalized to quantitative design of other probabilistic genetic devices in synthetic biology.

  7. Double swivel toggle release

    NASA Technical Reports Server (NTRS)

    King, Guy L.; Schneider, William C.

    1989-01-01

    A pyrotechnic actuated structural release device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body each attachable to one of a pair of structures to be joined. The fastener plate and the fastener body are fastened by a dual swivel toggle member. The toggle member is supported at one end on the fastener plate and mounted for universal pivotal movement thereon. Its other end is received in a central opening in the fastener body, and has a universally mounted retainer ring member. The toggle member is restrained by three retractable latching pins symmetrically disposed in equiangular spacing about the axis of the toggle member and positionable in latching engagement with the retainer ring member on the toggle member. Each pin is retractable by a pyrotechnic charge, the expanding gases of which are applied to a pressure receiving face on the latch pins to effect retraction from the ring member. While retraction of all three pins releases the ring member, the fastener is mechanically two fault tolerant since the failure of any single one or pair of the latch pins to retract results in an asymmetrical loading on the ring member and its dual pivotal movement ensures a release.

  8. Demonstrating Optothermal Actuators for an Autonomous Mems Microrobot

    DTIC Science & Technology

    2004-03-01

    of Toggled Microthermal Actuators,” Journal of Micromechanics and Microengineering, Vol. 14, pp 49-56, 2004. [10] S. Baglio, S. Castorina, L...127-132, 2000. [8] Y. Lai, J. McDonald, M. Kujath and T. Hubbard, “Force, Deflection and Power Measurements of Toggled Microthermal Actuators...Hubbard, "Force, Deflection and Power Measurements of Toggled Microthermal Actuators", Journal of Micromechanics and Microengineering, Vol. 14, pp 49

  9. Evaluation report for toggle switches: Texas Instruments, Inc., Apollo-type, and Daven Measurements part number 45000-XXX, job order 32-139

    NASA Technical Reports Server (NTRS)

    Labberton, D.

    1974-01-01

    A preliminary evaluation of environmental capabilities was undertaken on toggle switches and on Apollo-type toggle switches. The purpose of this evaluation was to take a first look at their tested capabilities for the purpose of determining whether the candidate hardware appears to have a good chance of successfully completing a detailed envrionmental qualification test program.

  10. Fermilab | Particle Physics Division

    Science.gov Websites

    Fermilab Search Toggle Fermilab Navbar Toggle Search Search Home Contact Phone Book Fermilab at Links Fermilab Home Contact Fermilab Phone Book Fermilab at Work Jobs at Fermilab Industrial

  11. Fermilab | Creative Services

    Science.gov Websites

    Search Toggle Fermilab Navbar Toggle Search Search Home Contact Phone Book Fermilab at Work Jobs Book Fermilab at Work For Industry Jobs Interact Facebook Twitter Instagram Google+ YouTube Flickr

  12. Home - House Budget Committee

    Science.gov Websites

    Initiatives Hearings Full Menu About Toggle Links Members History Staff Rules & Budget Law News Toggle Staff Rules & Budget Law News Press Releases Budget Digests HBC Publications Op-Eds Speeches &

  13. Fermilab | Photo Gallery

    Science.gov Websites

    Search Toggle Fermilab Navbar Toggle Search Search Home Contact Phone Book Fermilab at Work Jobs Science Security, Privacy, Legal Use of Cookies Quick Links Home Contact Phone Book Fermilab at Work For

  14. News | Argonne National Laboratory

    Science.gov Websites

    Skip to main content Argonne National Laboratory Toggle Navigation Toggle Search Home Learning solvers Home Learning Center Undergraduates Graduates Faculty Partners News & Events News & Events -4114 Contact Us Argonne Educational Programs is committed to providing a learning environment that

  15. Facilities | Argonne National Laboratory

    Science.gov Websites

    Skip to main content Argonne National Laboratory Toggle Navigation Toggle Search Research Facilities Advanced Powertrain Research Facility Center for Transportation Research Distributed Energy Research Center Engine Research Facility Heat Transfer Laboratory Materials Engineering Research Facility

  16. Safety | Argonne National Laboratory

    Science.gov Websites

    laboratory's ongoing effort to provide a safe and productive environment for employees, users, other site Skip to main content Argonne National Laboratory Toggle Navigation Toggle Search Energy Environment Careers Education Community Diversity Directory Energy Environment National Security User Facilities

  17. Increase Workshop | Argonne National Laboratory

    Science.gov Websites

    Skip to main content Argonne National Laboratory Toggle Navigation Toggle Search Home Learning solvers Home Learning Center Undergraduates Graduates Faculty Partners News & Events Faculty Visiting Us Argonne Educational Programs is committed to providing a learning environment that emphasizes the

  18. Artistic explorations of the brain

    PubMed Central

    Fetz, Eberhard E.

    2012-01-01

    The symbiotic relationships between art and the brain begin with the obvious fact that brain mechanisms underlie the creation and appreciation of art. Conversely, many spectacular images of neural structures have remarkable aesthetic appeal. But beyond its fascinating forms, the many functions performed by brain mechanisms provide a profound subject for aesthetic exploration. Complex interactions in the tangled neural networks in our brain miraculously generate coherent behavior and cognition. Neuroscientists tackle these phenomena with specialized methodologies that limit the scope of exposition and are comprehensible to an initiated minority. Artists can perform an end run around these limitations by representing the brain's remarkable functions in a manner that can communicate to a wide and receptive audience. This paper explores the ways that brain mechanisms can provide a largely untapped subject for artistic exploration. PMID:22347178

  19. Internship Opportunities | Argonne National Laboratory

    Science.gov Websites

    Skip to main content Argonne National Laboratory Toggle Navigation Toggle Search Home Learning -class research to tomorrow's STEM problem solvers Home Learning Center Undergraduates Graduates Faculty ) 252-4114 Contact Us Argonne Educational Programs is committed to providing a learning environment that

  20. π-tangle of a Jaynes-Cummings System and an Isolated Atom

    NASA Astrophysics Data System (ADS)

    Zhang, Hua-Ping; Qiang, Wen-Chao

    2018-04-01

    Using the π-tangle, we investigate entanglement properties of a quantum system consisted of a Jaynes-Cummings system and an isolated atom. We obtain analytical expressions of one-tangle, two-tangle and the π-tangle. Entanglement behaviors of the system are analyzed according to the analytical results. We find that the one-tangles have some relations with geometrical discord and entanglement sudden death never occurs in the total system.

  1. Intracellular calcium dynamics permit a Purkinje neuron model to perform toggle and gain computations upon its inputs

    PubMed Central

    Forrest, Michael D.

    2014-01-01

    Without synaptic input, Purkinje neurons can spontaneously fire in a repeating trimodal pattern that consists of tonic spiking, bursting and quiescence. Climbing fiber input (CF) switches Purkinje neurons out of the trimodal firing pattern and toggles them between a tonic firing and a quiescent state, while setting the gain of their response to Parallel Fiber (PF) input. The basis to this transition is unclear. We investigate it using a biophysical Purkinje cell model under conditions of CF and PF input. The model can replicate these toggle and gain functions, dependent upon a novel account of intracellular calcium dynamics that we hypothesize to be applicable in real Purkinje cells. PMID:25191262

  2. Non-Maximal Tripartite Entanglement Degradation of Dirac and Scalar Fields in Non-Inertial Frames

    NASA Astrophysics Data System (ADS)

    Salman, Khan; Niaz, Ali Khan; M. K., Khan

    2014-03-01

    The π-tangle is used to study the behavior of entanglement of a nonmaximal tripartite state of both Dirac and scalar fields in accelerated frame. For Dirac fields, the degree of degradation with acceleration of both one-tangle of accelerated observer and π-tangle, for the same initial entanglement, is different by just interchanging the values of probability amplitudes. A fraction of both one-tangles and the π-tangle always survives for any choice of acceleration and the degree of initial entanglement. For scalar field, the one-tangle of accelerated observer depends on the choice of values of probability amplitudes and it vanishes in the range of infinite acceleration, whereas for π-tangle this is not always true. The dependence of π-tangle on probability amplitudes varies with acceleration. In the lower range of acceleration, its behavior changes by switching between the values of probability amplitudes and for larger values of acceleration this dependence on probability amplitudes vanishes. Interestingly, unlike bipartite entanglement, the degradation of π-tangle against acceleration in the case of scalar fields is slower than for Dirac fields.

  3. Toggle mechanism for pinching metal tubes

    NASA Technical Reports Server (NTRS)

    Stengard, E. O. (Inventor)

    1979-01-01

    A toggle mechanism pinches a metal tube and maintains the tube in a pinched condition, without fracturing. The toggle mechanism includes a plunger translatable along a longitudinal axis, as well as a pair of links pivoted about a common axis extending through an end of the plunger. One of the links also pivots about a fixed axis. A free end of the other link carries a push link which the other link translates at right angles to the plunger longitudinal axis. First and second sides of the tube bear against a first stop block and are engaged by the push link when a compression spring, attached to the plunger, is suddenly released to irreversibly drive the plunger along its longitudinal axis so the pivot point of the two links is driven to an over travel position.

  4. Easily-wired toggle switch

    NASA Technical Reports Server (NTRS)

    Dean, W. T.; Stringer, E. J.

    1979-01-01

    Crimp-type connectors reduce assembly and disassembly time. With design, no switch preparation is necessary and socket contracts are crimped to wires inserted in module attached to back of toggle switch engaging pins inside module to make electrical connections. Wires are easily removed with standard detachment tool. Design can accommodate wires of any gage and as many terminals can be placed on switch as wire gage and switch dimensions will allow.

  5. Rapid convergence of optimal control in NMR using numerically-constructed toggling frames

    NASA Astrophysics Data System (ADS)

    Coote, Paul; Anklin, Clemens; Massefski, Walter; Wagner, Gerhard; Arthanari, Haribabu

    2017-08-01

    We present a numerical method for rapidly solving the Bloch equation for an arbitrary time-varying spin-1/2 Hamiltonian. The method relies on fast, vectorized computations such as summation and quaternion multiplication, rather than slow computations such as matrix exponentiation. A toggling frame is constructed in which the Hamiltonian is time-invariant, and therefore has a simple analytical solution. The key insight is that constructing this frame is faster than solving the system dynamics in the original frame. Rapidly solving the Bloch equations for an arbitrary Hamiltonian is particularly useful in the context of NMR optimal control. Optimal control theory can be used to design pulse shapes for a range of tasks in NMR spectroscopy. However, it requires multiple simulations of the Bloch equations at each stage of the algorithm, and for each relevant set of parameters (e.g. chemical shift frequencies). This is typically time consuming. We demonstrate that by working in an appropriate toggling frame, optimal control pulses can be generated much faster. We present a new alternative to the well-known GRAPE algorithm to continuously update the toggling-frame as the optimal pulse is generated, and demonstrate that this approach is extremely fast. The use and benefit of rapid optimal pulse generation is demonstrated for 19F fragment screening experiments.

  6. A novel image toggle tool for comparison of serial mammograms: automatic density normalization and alignment-development of the tool and initial experience.

    PubMed

    Honda, Satoshi; Tsunoda, Hiroko; Fukuda, Wataru; Saida, Yukihisa

    2014-12-01

    The purpose is to develop a new image toggle tool with automatic density normalization (ADN) and automatic alignment (AA) for comparing serial digital mammograms (DMGs). We developed an ADN and AA process to compare the images of serial DMGs. In image density normalization, a linear interpolation was applied by taking two points of high- and low-brightness areas. The alignment was calculated by determining the point of the greatest correlation while shifting the alignment between the current and prior images. These processes were performed on a PC with a 3.20-GHz Xeon processor and 8 GB of main memory. We selected 12 suspected breast cancer patients who had undergone screening DMGs in the past. Automatic processing was retrospectively performed on these images. Two radiologists subjectively evaluated them. The process of the developed algorithm took approximately 1 s per image. In our preliminary experience, two images could not be aligned approximately. When they were aligned, image toggling allowed detection of differences between examinations easily. We developed a new tool to facilitate comparative reading of DMGs on a mammography viewing system. Using this tool for toggling comparisons might improve the interpretation efficiency of serial DMGs.

  7. Immunocytochemical Studies of Neurofibrillary Tangles

    PubMed Central

    Yen, Shu-Hui C.; Gaskin, Felicia; Terry, Robert D.

    1981-01-01

    The molecular nature of neurofibrillary tangles of senile dementia of the Alzheimer type (SDAT) was studied by immunoperoxidase and immunofluorescence techniques. Five antiserums, including anti-humanbrain-2-cycle-purified-microtubule-fractions (2 × MT), anti-calf-brain-2 × MT, anti-sea-urchin-egg-tubulin, antibeef-brain-tubulin, and anti-human-brain-neurofilament(NF)-210-kilodalton(kd)-protein were tested for their binding to neurofibrillary tangles. The antihuman-2 × MT serum stained structures resembling neurofibrillary tangles, neurites of neuritic plaques, and microglialike cells in SDAT brains, but no such staining pattern was detected in normal brain sections. In neurons isolated from SDAT brains, about 40% of the tangles were labeled by the anti-human-2×MT serum with an identical pattern. Other antiserums tested did not preferentially bind tanglelike structures in tissue sections and bound to less than 5% of the tangles in isolated neurons. These results suggest that the antigenic sites of tubulin and NF proteins are not shared by neurofibrillary tangles. Different from the calf preparation, the human-2 × MT fractions contained a prominent protein band that was identical to ferritin in molecular weight and cross-reacted with anti-human-2 × MT and anti-human-ferritin serums. However, antiserums to this ferritinlike protein, or anti-ferritin, did not stain neurofibrillary tangles. Although neither the calf 2 × MT nor two other human MT fractions failed to elicit an antiserum that stained tangles, these fractions were able to remove the antihuman-2 × MT serum activity that binds to tangles. The data suggest that the protein (or proteins) that makes up neurofibrillary tangles of SDAT is present in various quantities in microtubule fractions of normal brain. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11Figure 12Figure 13Figure 14Figure 15Figure 16 PMID:7020426

  8. Whole-brain perfusion CT using a toggling table technique to predict final infarct volume in acute ischemic stroke.

    PubMed

    Schrader, I; Wilk, D; Jansen, O; Riedel, C

    2013-09-01

    To evaluate how accurately final infarct volume in acute ischemic stroke can be predicted with perfusion CT (PCT) using a 64-MDCT unit and the toggling table technique. Retrospective analysis of 89 patients with acute ischemic stroke who underwent CCT, CT angiography (CTA) and PCT using the "toggling table" technique within the first three hours after symptom onset. In patients with successful thrombolytic therapy (n = 48) and in those without effective thrombolytic therapy (n = 41), the infarct volume and the volume of the penumbra on PCT were compared to the infarct size on follow-up images (CT or MRI) performed within 8 days. The feasibility of complete infarct volume prediction by 8 cm cranio-caudal coverage was evaluated. The correlation between the volume of hypoperfusion on PCT defined by cerebral blood volume reduction and final infarct volume was strongest in patients with successful thrombolytic therapy with underestimation of the definite infarct volume by 8.5 ml on average. The CBV map had the greatest prognostic value. In patients without successful thrombolytic therapy, the final infarct volume was overestimated by 12.1 ml compared to the MTT map on PCT. All infarcts were detected completely. There were no false-positive or false-negative results. Using PCT and the "toggling table" technique in acute stroke patients is helpful for the rapid and accurate quantification of the minimal final infarct and is therefore a prognostic parameter which has to be evaluated in further studies to assess its impact on therapeutic decision. ▶ Using PCT and the “toggling table technique” allows accurate quantification of the infarct core and penumbra. ▶ It is possible to record dynamic perfusion parameters quickly and easily of almost the entire supratentorial brain volume on a 64-slice MDCT unit. ▶ The technique allows identification of those patients who could profit from thrombolytic therapy outside the established time intervals. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Continuity of neuropil threads with tangle-bearing and tangle-free neurons in Alzheimer disease cortex. A confocal laser scanning microscopy study.

    PubMed

    Schmidt, M L; Murray, J M; Trojanowski, J Q

    1993-04-01

    Neuropil threads (NTs) are abnormal processes that are associated with tangle-bearing neurons in gray matter areas of Alzheimer disease (AD) brains. Although NTs contain paired helical filaments (PHFs) and share multiple tau epitopes with neurobrillary tangles (NFTs), the relationship between NTs and tangle-bearing neurons is unclear. For this reason, we assessed the continuity of NTs with tangle-bearing and tangle-free neurons. Since astrocytes express low levels of tau and rarely have been shown to contain PHFs, we also examined the relationship of NTs to cortical astrocytes. This was done using histochemical and immunochemical methods in conjunction with confocal laser scanning microscopy to examine NTs in amygdala and entorhinal cortex of seven AD brains. Only a small fraction of NTs (< 1%) in 3.5 x 10(6) microns 3 of amygdala and entorhinal cortex could be traced to local neurons with NFTs or to neurons that did not contain NFTs, and no NTs were continuous with cortical astrocytes. These results indicate that only a very small percentage of NTs in entorhinal cortex and amygdala occur in the most proximal segments of processes that emanate from tangle-bearing or tangle-free neurons. This implies that the majority of NTs reside in the distal parts of dendrites and/or the terminal arborizations of axons or that NTs are discontinuous abnormalities. Taken together, these data suggest that NTs could disrupt local and long distance neuronal circuitry and thereby contribute to the cognitive impairments seen in AD patients.

  10. Toggling Bistable Atoms via Mechanical Switching of Bond Angle

    NASA Astrophysics Data System (ADS)

    Sweetman, Adam; Jarvis, Sam; Danza, Rosanna; Bamidele, Joseph; Gangopadhyay, Subhashis; Shaw, Gordon A.; Kantorovich, Lev; Moriarty, Philip

    2011-04-01

    We reversibly switch the state of a bistable atom by direct mechanical manipulation of bond angle using a dynamic force microscope. Individual buckled dimers at the Si(100) surface are flipped via the formation of a single covalent bond, actuating the smallest conceivable in-plane toggle switch (two atoms) via chemical force alone. The response of a given dimer to a flip event depends critically on both the local and nonlocal environment of the target atom—an important consideration for future atomic scale fabrication strategies.

  11. Methylene blue does not reverse existing neurofibrillary tangle pathology in the rTg4510 mouse model of tauopathy.

    PubMed

    Spires-Jones, Tara L; Friedman, Taylor; Pitstick, Rose; Polydoro, Manuela; Roe, Allyson; Carlson, George A; Hyman, Bradley T

    2014-03-06

    Alzheimer's disease is characterized pathologically by aggregation of amyloid beta into senile plaques and aggregation of pathologically modified tau into neurofibrillary tangles. While changes in amyloid processing are strongly implicated in disease initiation, the recent failure of amyloid-based therapies has highlighted the importance of tau as a therapeutic target. "Tangle busting" compounds including methylene blue and analogous molecules are currently being evaluated as therapeutics in Alzheimer's disease. Previous studies indicated that methylene blue can reverse tau aggregation in vitro after 10 min, and subsequent studies suggested that high levels of drug reduce tau protein levels (assessed biochemically) in vivo. Here, we tested whether methylene blue could remove established neurofibrillary tangles in the rTg4510 model of tauopathy, which develops robust tangle pathology. We find that 6 weeks of methylene blue dosing in the water from 16 months to 17.5 months of age decreases soluble tau but does not remove sarkosyl insoluble tau, or histologically defined PHF1 or Gallyas positive tangle pathology. These data indicate that methylene blue treatment will likely not rapidly reverse existing tangle pathology. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  12. Methylene blue does not reverse existing neurofibrillary tangle pathology in the rTg4510 mouse model of tauopathy

    PubMed Central

    Spires-Jones, Tara L; Friedman, Taylor; Pitstick, Rose; Polydoro, Manuela; Roe, Allyson; Carlson, George A; Hyman, Bradley T

    2014-01-01

    Alzheimer's disease is characterized pathologically by aggregation of amyloid beta into senile plaques and aggregation of pathologically modified tau into neurofibrillary tangles. While changes in amyloid processing are strongly implicated in disease initiation, the recent failure of amyloid-based therapies has highlighted the importance of tau as a therapeutic target. “Tangle busting” compounds including methylene blue and analogous molecules are currently being evaluated as therapeutics in Alzheimer's disease. Previous studies indicated that methylene blue can reverse tau aggregation in vitro after 10 minutes, and subsequent studies suggested that high levels of drug reduce tau protein levels (assessed biochemically) in vivo. Here, we tested whether methylene blue could remove established neurofibrillary tangles in the rTg4510 model of tauopathy, which develops robust tangle pathology. We find that 6 weeks of methylene blue dosing in the water from 16 months to 17.5 months of age decreases soluble tau but does not remove sarkosyl insoluble tau, or histologically defined PHF1 or Gallyas positive tangle pathology. These data indicate that methylene blue treatment will likely not rapidly reverse existing tangle pathology. PMID:24462887

  13. Oh What a Tangled Biofilm Web Bacteria Weave

    MedlinePlus

    ... What a Tangled Biofilm Web Bacteria Weave Inside Life Science View All Articles | Inside Life Science Home Page Oh What a Tangled Biofilm Web ... Cellular Conversations Learning from Bacterial Chatter This Inside Life Science article also appears on LiveScience . Learn about related ...

  14. On monogamy of four-qubit entanglement

    NASA Astrophysics Data System (ADS)

    Sharma, S. Shelly; Sharma, N. K.

    2018-07-01

    Our main result is a monogamy inequality satisfied by the entanglement of a focus qubit (one-tangle) in a four-qubit pure state and entanglement of subsystems. Analytical relations between three-tangles of three-qubit marginal states, two-tangles of two-qubit marginal states and unitary invariants of four-qubit pure state are used to obtain the inequality. The contribution of three-tangle to one-tangle is found to be half of that suggested by a simple extension of entanglement monogamy relation for three qubits. On the other hand, an additional contribution due to a two-qubit invariant which is a function of three-way correlations is found. We also show that four-qubit monogamy inequality conjecture of Regula et al. (Phys Rev Lett 113:110501, 2014), in which three-tangles are raised to the power 3/2, does not estimate the residual correlations, correctly, for certain subsets of four-qubit states. A lower bound on residual four-qubit correlations is obtained.

  15. Two forms for 3-uniform states of eight-qubits

    NASA Astrophysics Data System (ADS)

    Zha, Xinwei; Da, Zhang; Ahmed, Irfan; Zhang, Yanpeng

    2018-05-01

    In this paper, we study the relations between average bipartite entanglement and the n-tangle of eight-qubits. We have derived two forms for 3-uniform states of eight-qubits. One form has the n-tangle equal to zero; the other form has the n-tangle equal to unity.

  16. OPERATIONS TOGGLE, ARBOR and BEDROCK Events: DIAMOND SCULLS, DIDO QUEEN, HUSKY ACE, MING BLADE, HYBLA FAIR and DINING CAR, 20 July 1972 - 5 April 1975

    DTIC Science & Technology

    1987-11-30

    1975 to study weapons effects . All six were tunnel-type nuclear tests. The following table summarizes data on these events: OPERATION TOGGLE ARBOR...194 nuclear device tests conducted, 161 were for weapons related or effects purposes, and 33 were safety ex- periments. An additional 22 nuclear...on 25 April 1962 until the last atmospheric test on 4 November 1962, 40 weapons development and weapons effects tests were conducted as part of

  17. Inducing Autophagy by Rapamycin Before, but Not After, the Formation of Plaques and Tangles Ameliorates Cognitive Deficits

    PubMed Central

    Majumder, Smita; Richardson, Arlan; Strong, Randy; Oddo, Salvatore

    2011-01-01

    Previous studies have shown that inducing autophagy ameliorates early cognitive deficits associated with the build-up of soluble amyloid-β (Aβ). However, the effects of inducing autophagy on plaques and tangles are yet to be determined. While soluble Aβ and tau represent toxic species in Alzheimer's disease (AD) pathogenesis, there is well documented evidence that plaques and tangles also are detrimental to normal brain function. Thus, it is critical to assess the effects of inducing autophagy in an animal model with established plaques and tangles. Here we show that rapamycin, when given prophylactically to 2-month-old 3xTg-AD mice throughout their life, induces autophagy and significantly reduces plaques, tangles and cognitive deficits. In contrast, inducing autophagy in 15-month-old 3xTg-AD mice, which have established plaques and tangles, has no effects on AD-like pathology and cognitive deficits. In conclusion, we show that autophagy induction via rapamycin may represent a valid therapeutic strategy in AD when administered early in the disease progression. PMID:21980451

  18. Novel toggle-rate based energy-efficient scheme for heavy load real-time IM-DD OFDM-PON with ONU LLID identification in time-domain using amplitude decision.

    PubMed

    Qin, Youxiang; Zhang, Junjie

    2017-07-10

    A novel low complexity and energy-efficient scheme by controlling the toggle-rate of ONU with time-domain amplitude identification is proposed for a heavy load downlink in an intensity-modulation and direct-detection orthogonal frequency division multiplexing passive optical network (IM-DD OFDM-PON). In a conventional OFDM-PON downlink, all ONUs have to perform demodulation for all the OFDM frames in a broadcast way no matter whether the frames are targeted to or not, which causes a huge energy waste. However, in our scheme, the optical network unit (ONU) logical link identifications (LLIDs) are inserted into each downlink OFDM frame in time-domain at the optical line terminal (OLT) side. At the ONU side, the LLID is obtained with a low complexity and high precision amplitude identification method. The ONU sets the toggle-rate of demodulation module to zero when the frames are not targeted to, which avoids unnecessary digital signal processing (DSP) energy consumption. Compared with the sleep-mode methods consisting of clock recovery and synchronization, toggle-rate shows its advantage in fast changing, which is more suitable for the heavy load scenarios. Moreover, for the first time to our knowledge, the characteristics of the proposed scheme are investigated in a real-time IM-DD OFDM system, which performs well at the received optical power as low as -21dBm. The experimental results show that 25.1% energy consumption can be saved in the receiver compared to the conventional configurations.

  19. Combining a Toggle Switch and a Repressilator within the AC-DC Circuit Generates Distinct Dynamical Behaviors.

    PubMed

    Perez-Carrasco, Ruben; Barnes, Chris P; Schaerli, Yolanda; Isalan, Mark; Briscoe, James; Page, Karen M

    2018-04-25

    Although the structure of a genetically encoded regulatory circuit is an important determinant of its function, the relationship between circuit topology and the dynamical behaviors it can exhibit is not well understood. Here, we explore the range of behaviors available to the AC-DC circuit. This circuit consists of three genes connected as a combination of a toggle switch and a repressilator. Using dynamical systems theory, we show that the AC-DC circuit exhibits both oscillations and bistability within the same region of parameter space; this generates emergent behaviors not available to either the toggle switch or the repressilator alone. The AC-DC circuit can switch on oscillations via two distinct mechanisms, one of which induces coherence into ensembles of oscillators. In addition, we show that in the presence of noise, the AC-DC circuit can behave as an excitable system capable of spatial signal propagation or coherence resonance. Together, these results demonstrate how combinations of simple motifs can exhibit multiple complex behaviors. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

  20. Pretangles and neurofibrillary changes: similarities and differences between AD and CBD based on molecular and morphological evolution.

    PubMed

    Uchihara, Toshiki

    2014-12-01

    Pretangles are cytoplasmic tau immunoreactivity in neurons without apparent formation of fibrillary structures. In Alzheimer disease, such tau deposition is considered to represent a premature state prior to fibril formation (AD-pretangles), later to form neurofibrillary tangles and finally ghost tangles. This morphological evolution from pretangles to ghost tangles is in parallel with their profile shift from four repeat (4R) tau-positive pretangles to three repeat (3R) tau-positive ghost tangles with both positive neurofibrillary tangles in between. This complementary shift of tau profile from 4R to 3R suggests that these tau epitopes are represented interchangeably along tangle evolution. Similar tau immunoreactivity without fibril formation is also observed in corticobasal degeneration (CBD-pretangles). CBD-pretangles and AD-pretangles share: (i) selective 4R tau immunoreactivity without involvement of 3R tau; and (ii) argyrophilia with Gallyas silver impregnation. However, CBD-pretangles neither evolve into ghost tangles nor exhibit 3R tau immunoreactivity even at the advanced stage. Because electron microscopic studies on these pretangles are quite limited, it remains to be clarified whether such differences in later evolution are related to their primary ultrastructures, potentially distinct between AD and CBD. As double staining for 3R and 4R tau clarified complementary shift from 4R to 3R tau along evolution from pretangles to ghost tangles, double immunoelectron microscopy, if possible, may clarify similar profile shifts in relation to each tau fibril at the ultrastructural dimension. This will provide a unique viewpoint on how molecular (epitope) representations are related to pathogenesis of fibrillary components. © 2014 Japanese Society of Neuropathology.

  1. Quickly Removable Valve

    NASA Technical Reports Server (NTRS)

    Robbins, John S.

    1988-01-01

    Unit removed with minimal disturbance. Valve inlet and outlet ports adjacent to each other on same side of valve body. Ports inserted into special manifold on fluid line. Valve body attached to manifold by four bolts or, alternatively, by toggle clamps. Electromechanical actuator moves in direction parallel to fluid line to open and close valve. When necessary to clean valve, removed simply by opening bolts or toggle clamps. No need to move or separate ports of fluid line. Valve useful where disturbance of fluid line detrimental or where fast maintenance essential - in oil and chemical industries, automotive vehicles, aircraft, and powerplants.

  2. Abnormally phosphorylated tau protein in senile dementia of Lewy body type and Alzheimer disease: evidence that the disorders are distinct.

    PubMed

    Strong, C; Anderton, B H; Perry, R H; Perry, E K; Ince, P G; Lovestone, S

    1995-01-01

    The relationship between Alzheimer disease (AD) and dementia with Lewy bodies (senile dementia Lewy body type, or SDLT) and dementia in Parkinson's disease is unclear. AD pathology is characterised by both amyloid deposition and abnormal phosphorylation of tau in paired helical filaments (PHF-tau). In AD, abnormally phosphorylated PHF-tau is present in neurofibrillary tangles, in neuritic processes of senile plaques, and also in neuropil threads dispersed throughout the cerebral cortex. Cortical homogenates from 12 cases each of AD and SDLT, 13 cases of Parkinson's disease, and 11 normal controls were examined by Western blot analysis with antibodies that detect PHF-tau. No PHF-tau was found in Parkinson's disease or control cortex. No PHF-tau was found in SDLT cases without histological evidence of tangles. PHF-tau was detectable in SDLT cases with a low density of tangles, and large amounts of PHF-tau were present in AD cases. This study demonstrates that abnormally phosphorylated PHF-tau is only present where tangles are found and not in SDLT cases without tangles or with only occasional tangles. It is concluded that Lewy body dementias are distinct at a molecular level from AD.

  3. Beta amyloid deposition and neurofibrillary tangles spontaneously occur in the brains of captive cheetahs (Acinonyx jubatus).

    PubMed

    Serizawa, S; Chambers, J K; Une, Y

    2012-03-01

    Alzheimer disease is a dementing disorder characterized pathologically by Aβ deposition, neurofibrillary tangles, and neuronal loss. Although aged animals of many species spontaneously develop Aβ deposits, only 2 species (chimpanzee and wolverine) have been reported to develop Aβ deposits and neurofibrillary tangles in the same individual. Here, the authors demonstrate the spontaneous occurrence of Aβ deposits and neurofibrillary tangles in captive cheetahs (Acinonyx jubatus). Among 22 cheetahs examined in this study, Aβ deposits were observed in 13. Immunostaining (AT8) revealed abnormal intracellular tau immunoreactivity in 10 of the cheetahs with Aβ deposits, and they were mainly distributed in the parahippocampal cortex and CA1 in a fashion similar to that in human patients with Alzheimer disease. Ultrastructurally, bundles of straight filaments filled the neuronal somata and axons, consistent with tangles. Interestingly, 2 of the cheetahs with the most severe abnormal tau immunoreactivity showed clinical cognitive dysfunction. The authors conclude that cheetahs spontaneously develop age-related neurodegenerative disease with pathologic changes similar to Alzheimer disease.

  4. Tau pathology does not affect experience-driven single-neuron and network-wide Arc/Arg3.1 responses.

    PubMed

    Rudinskiy, Nikita; Hawkes, Jonathan M; Wegmann, Susanne; Kuchibhotla, Kishore V; Muzikansky, Alona; Betensky, Rebecca A; Spires-Jones, Tara L; Hyman, Bradley T

    2014-06-10

    Intraneuronal neurofibrillary tangles (NFTs) - a characteristic pathological feature of Alzheimer's and several other neurodegenerative diseases - are considered a major target for drug development. Tangle load correlates well with the severity of cognitive symptoms and mouse models of tauopathy are behaviorally impaired. However, there is little evidence that NFTs directly impact physiological properties of host neurons. Here we used a transgenic mouse model of tauopathy to study how advanced tau pathology in different brain regions affects activity-driven expression of immediate-early gene Arc required for experience-dependent consolidation of long-term memories. We demonstrate in vivo that visual cortex neurons with tangles are as likely to express comparable amounts of Arc in response to structured visual stimulation as their neighbors without tangles. Probability of experience-dependent Arc response was not affected by tau tangles in both visual cortex and hippocampal pyramidal neurons as determined postmortem. Moreover, whole brain analysis showed that network-wide activity-driven Arc expression was not affected by tau pathology in any of the brain regions, including brain areas with the highest tangle load. Our findings suggest that intraneuronal NFTs do not affect signaling cascades leading to experience-dependent gene expression required for long-term synaptic plasticity.

  5. The occult aftermath of boxing.

    PubMed Central

    Roberts, G W; Allsop, D; Bruton, C

    1990-01-01

    The repeated head trauma experienced by boxers can lead to the development of dementia pugilistica (DP)--punch drunk syndrome. The neuropathology of DP in a classic report by Corsellis et al describes the presence of numerous neurofibrillary tangles in the absence of plaques, in contrast to the profusion of tangles and plaques seen in Alzheimer's disease (AD). The DP cases used in that report were re-investigated with immunocytochemical methods and an antibody raised to the beta-protein present in AD plaques. We found that all DP cases with substantial tangle formation showed evidence of extensive beta-protein immunoreactive deposits (plaques). These diffuse "plaques" were not visible with Congo-red or standard silver stains. The degree of beta-protein deposition was comparable to that seen in AD. Our data indicate that the present neuropathological description of DP (tangles but no plaques) should be altered to acknowledge the presence of substantial beta-protein deposition (plaques). The molecular markers present in the plaques and tangles of DP are the same as those in AD. Similarities in clinical symptoms, distribution of pathology and neurochemical deficits also exist. Epidemiological studies have shown that head injury is a risk factor in AD. It is probable that DP and AD share common pathogenic mechanisms leading to tangle and plaque formation. Images PMID:2191084

  6. Joint for deployable structures

    NASA Technical Reports Server (NTRS)

    Craighead, N. D., II; Preliasco, R. J.; Hult, T. D. (Inventor)

    1985-01-01

    A joint is described for connecting a pair of beams to pivot them between positions in alignment or beside one another, which is of light weight and which operates in a controlled manner. The joint includes a pair of fittings and at least one center link having opposite ends pivotally connected to opposite fittings and having axes that pass through centerplates of the fittings. A control link having opposite ends pivotally connected to the different fittings controls their relative orientations, and a toggle assemly holds the fittings in the deployed configuration wherein they are aligned. The fittings have stops that lie on one side of the centerplane opposite the toggle assembly.

  7. Membrane-bound MinDE complex acts as a toggle switch that drives Min oscillation coupled to cytoplasmic depletion of MinD

    PubMed Central

    Vecchiarelli, Anthony G.; Li, Min; Mizuuchi, Michiyo; Hwang, Ling Chin; Seol, Yeonee; Neuman, Keir C.; Mizuuchi, Kiyoshi

    2016-01-01

    The Escherichia coli Min system self-organizes into a cell-pole to cell-pole oscillator on the membrane to prevent divisions at the cell poles. Reconstituting the Min system on a lipid bilayer has contributed to elucidating the oscillatory mechanism. However, previous in vitro patterns were attained with protein densities on the bilayer far in excess of those in vivo and failed to recapitulate the standing wave oscillations observed in vivo. Here we studied Min protein patterning at limiting MinD concentrations reflecting the in vivo conditions. We identified “burst” patterns—radially expanding and imploding binding zones of MinD, accompanied by a peripheral ring of MinE. Bursts share several features with the in vivo dynamics of the Min system including standing wave oscillations. Our data support a patterning mechanism whereby the MinD-to-MinE ratio on the membrane acts as a toggle switch: recruiting and stabilizing MinD on the membrane when the ratio is high and releasing MinD from the membrane when the ratio is low. Coupling this toggle switch behavior with MinD depletion from the cytoplasm drives a self-organized standing wave oscillator. PMID:26884160

  8. Membrane-bound MinDE complex acts as a toggle switch that drives Min oscillation coupled to cytoplasmic depletion of MinD.

    PubMed

    Vecchiarelli, Anthony G; Li, Min; Mizuuchi, Michiyo; Hwang, Ling Chin; Seol, Yeonee; Neuman, Keir C; Mizuuchi, Kiyoshi

    2016-03-15

    The Escherichia coli Min system self-organizes into a cell-pole to cell-pole oscillator on the membrane to prevent divisions at the cell poles. Reconstituting the Min system on a lipid bilayer has contributed to elucidating the oscillatory mechanism. However, previous in vitro patterns were attained with protein densities on the bilayer far in excess of those in vivo and failed to recapitulate the standing wave oscillations observed in vivo. Here we studied Min protein patterning at limiting MinD concentrations reflecting the in vivo conditions. We identified "burst" patterns--radially expanding and imploding binding zones of MinD, accompanied by a peripheral ring of MinE. Bursts share several features with the in vivo dynamics of the Min system including standing wave oscillations. Our data support a patterning mechanism whereby the MinD-to-MinE ratio on the membrane acts as a toggle switch: recruiting and stabilizing MinD on the membrane when the ratio is high and releasing MinD from the membrane when the ratio is low. Coupling this toggle switch behavior with MinD depletion from the cytoplasm drives a self-organized standing wave oscillator.

  9. Tuning stochastic transition rates in a bistable genetic network.

    NASA Astrophysics Data System (ADS)

    Chickarmane, Vijay; Peterson, Carsten

    2009-03-01

    We investigate the stochastic dynamics of a simple genetic network, a toggle switch, in which the system makes transitions between the two alternative states. Our interest is in exploring whether such stochastic transitions, which occur due to the intrinsic noise such as transcriptional and degradation events, can be slowed down/speeded up, without changing the mean expression levels of the two genes, which comprise the toggle network. Such tuning is achieved by linking a signaling network to the toggle switch. The signaling network comprises of a protein, which can exist either in an active (phosphorylated) or inactive (dephosphorylated) form, and where its state is determined by one of the genetic network components. The active form of the protein in turn feeds back on the dynamics of the genetic network. We find that the rate of stochastic transitions from one state to the other, is determined essentially by the speed of phosphorylation, and hence the rate can be modulated by varying the phosphatase levels. We hypothesize that such a network architecture can be implemented as a general mechanism for controlling transition rates and discuss applications in population studies of two differentiated cell lineages, ex: the myeloid/erythroid lineage in hematopoiesis.

  10. Entorhinal Cortex: Antemortem Cortical Thickness and Postmortem Neurofibrillary Tangles and Amyloid Pathology.

    PubMed

    Thaker, A A; Weinberg, B D; Dillon, W P; Hess, C P; Cabral, H J; Fleischman, D A; Leurgans, S E; Bennett, D A; Hyman, B T; Albert, M S; Killiany, R J; Fischl, B; Dale, A M; Desikan, R S

    2017-05-01

    The entorhinal cortex, a critical gateway between the neocortex and hippocampus, is one of the earliest regions affected by Alzheimer disease-associated neurofibrillary tangle pathology. Although our prior work has automatically delineated an MR imaging-based measure of the entorhinal cortex, whether antemortem entorhinal cortex thickness is associated with postmortem tangle burden within the entorhinal cortex is still unknown. Our objective was to evaluate the relationship between antemortem MRI measures of entorhinal cortex thickness and postmortem neuropathological measures. We evaluated 50 participants from the Rush Memory and Aging Project with antemortem structural T1-weighted MR imaging and postmortem neuropathologic assessments. Here, we focused on thickness within the entorhinal cortex as anatomically defined by our previously developed MR imaging parcellation system (Desikan-Killiany Atlas in FreeSurfer). Using linear regression, we evaluated the association between entorhinal cortex thickness and tangles and amyloid-β load within the entorhinal cortex and medial temporal and neocortical regions. We found a significant relationship between antemortem entorhinal cortex thickness and entorhinal cortex ( P = .006) and medial temporal lobe tangles ( P = .002); we found no relationship between entorhinal cortex thickness and entorhinal cortex ( P = .09) and medial temporal lobe amyloid-β ( P = .09). We also found a significant association between entorhinal cortex thickness and cortical tangles ( P = .003) and amyloid-β ( P = .01). We found no relationship between parahippocampal gyrus thickness and entorhinal cortex ( P = .31) and medial temporal lobe tangles ( P = .051). Our findings indicate that entorhinal cortex-associated in vivo cortical thinning may represent a marker of postmortem medial temporal and neocortical Alzheimer disease pathology. © 2017 by American Journal of Neuroradiology.

  11. TANGLE: Two-Level Support Vector Regression Approach for Protein Backbone Torsion Angle Prediction from Primary Sequences

    PubMed Central

    Song, Jiangning; Tan, Hao; Wang, Mingjun; Webb, Geoffrey I.; Akutsu, Tatsuya

    2012-01-01

    Protein backbone torsion angles (Phi) and (Psi) involve two rotation angles rotating around the Cα-N bond (Phi) and the Cα-C bond (Psi). Due to the planarity of the linked rigid peptide bonds, these two angles can essentially determine the backbone geometry of proteins. Accordingly, the accurate prediction of protein backbone torsion angle from sequence information can assist the prediction of protein structures. In this study, we develop a new approach called TANGLE (Torsion ANGLE predictor) to predict the protein backbone torsion angles from amino acid sequences. TANGLE uses a two-level support vector regression approach to perform real-value torsion angle prediction using a variety of features derived from amino acid sequences, including the evolutionary profiles in the form of position-specific scoring matrices, predicted secondary structure, solvent accessibility and natively disordered region as well as other global sequence features. When evaluated based on a large benchmark dataset of 1,526 non-homologous proteins, the mean absolute errors (MAEs) of the Phi and Psi angle prediction are 27.8° and 44.6°, respectively, which are 1% and 3% respectively lower than that using one of the state-of-the-art prediction tools ANGLOR. Moreover, the prediction of TANGLE is significantly better than a random predictor that was built on the amino acid-specific basis, with the p-value<1.46e-147 and 7.97e-150, respectively by the Wilcoxon signed rank test. As a complementary approach to the current torsion angle prediction algorithms, TANGLE should prove useful in predicting protein structural properties and assisting protein fold recognition by applying the predicted torsion angles as useful restraints. TANGLE is freely accessible at http://sunflower.kuicr.kyoto-u.ac.jp/~sjn/TANGLE/. PMID:22319565

  12. Theoretical Bounds of Direct Binary Search Halftoning.

    PubMed

    Liao, Jan-Ray

    2015-11-01

    Direct binary search (DBS) produces the images of the best quality among half-toning algorithms. The reason is that it minimizes the total squared perceived error instead of using heuristic approaches. The search for the optimal solution involves two operations: (1) toggle and (2) swap. Both operations try to find the binary states for each pixel to minimize the total squared perceived error. This error energy minimization leads to a conjecture that the absolute value of the filtered error after DBS converges is bounded by half of the peak value of the autocorrelation filter. However, a proof of the bound's existence has not yet been found. In this paper, we present a proof that shows the bound existed as conjectured under the condition that at least one swap occurs after toggle converges. The theoretical analysis also indicates that a swap with a pixel further away from the center of the autocorrelation filter results in a tighter bound. Therefore, we propose a new DBS algorithm which considers toggle and swap separately, and the swap operations are considered in the order from the edge to the center of the filter. Experimental results show that the new algorithm is more efficient than the previous algorithm and can produce half-toned images of the same quality as the previous algorithm.

  13. Fusion of infrared polarization and intensity images based on improved toggle operator

    NASA Astrophysics Data System (ADS)

    Zhu, Pan; Ding, Lei; Ma, Xiaoqing; Huang, Zhanhua

    2018-01-01

    Integration of infrared polarization and intensity images has been a new topic in infrared image understanding and interpretation. The abundant infrared details and target from infrared image and the salient edge and shape information from polarization image should be preserved or even enhanced in the fused result. In this paper, a new fusion method is proposed for infrared polarization and intensity images based on the improved multi-scale toggle operator with spatial scale, which can effectively extract the feature information of source images and heavily reduce redundancy among different scale. Firstly, the multi-scale image features of infrared polarization and intensity images are respectively extracted at different scale levels by the improved multi-scale toggle operator. Secondly, the redundancy of the features among different scales is reduced by using spatial scale. Thirdly, the final image features are combined by simply adding all scales of feature images together, and a base image is calculated by performing mean value weighted method on smoothed source images. Finally, the fusion image is obtained by importing the combined image features into the base image with a suitable strategy. Both objective assessment and subjective vision of the experimental results indicate that the proposed method obtains better performance in preserving the details and edge information as well as improving the image contrast.

  14. Medial Patellofemoral Ligament Reconstruction Procedure Using a Suspensory Femoral Fixation System

    PubMed Central

    Nakagawa, Shuji; Arai, Yuji; Kan, Hiroyuki; Ueshima, Keiichiro; Ikoma, Kazuya; Terauchi, Ryu; Kubo, Toshikazu

    2013-01-01

    Recurrent patellar dislocation has recently been treated with anatomic medial patellofemoral ligament (MPFL) reconstruction using a semitendinosus muscle tendon. Although it is necessary to add tension to fix the tendon graft without loading excess stress on the patellofemoral joint, adjustment of the tension can be difficult. To resolve this problem, we developed an MPFL reconstruction procedure using the ToggleLoc Fixation Device (Biomet, Warsaw, IN), in which the semitendinosus muscle tendon is folded and used as a double-bundle tendon graft and 2 bone tunnels and 1 bone tunnel are made on the patellar and femoral sides, respectively. The patellar side of the tendon graft is fixed with an EndoButton (Smith & Nephew, London, England), and the femoral side is fixed with the ToggleLoc. Stepless adjustment of tension of the tendon graft is possible by reducing the size of the loop of the ToggleLoc hung onto the tendon graft. It may be useful to position the patella in the center of the femoral sulcus by confirming the patellofemoral joint fitting. Stability can be confirmed by loading lateral stress on the patella in the extended knee joint. This procedure is less invasive because opening of the lateral side of the femur is not necessary, and it may be useful for MPFL reconstruction. PMID:24892014

  15. Heteroclinic tangle phenomena in nanomagnets subject to time-harmonic excitations

    NASA Astrophysics Data System (ADS)

    Serpico, C.; Quercia, A.; Bertotti, G.; d'Aquino, M.; Mayergoyz, I.; Perna, S.; Ansalone, P.

    2015-05-01

    Magnetization dynamics in uniformly magnetized nanomagnets excited by time-harmonic (AC) external fields or spin-polarized injected currents is considered. The analysis is focused on the behaviour of the AC-excited dynamics near saddle equilibria. It turns out that this dynamics has a chaotic character at moderately low power level. This chaotic and fractal nature is due to the phenomenon of heteroclinic tangle which is produced by the combined effect of AC-excitations and saddle type dynamics. By using the perturbation technique based on Melnikov function, analytical formulas for the threshold AC excitation amplitudes necessary to create the heteroclinic tangle are derived. Both the cases of AC applied fields and AC spin-polarized injected currents are treated. Then, by means of numerical simulations, we show how heteroclinic tangle is accompanied by the erosion of the safe basin around the stable regimes.

  16. Interaction of Neuritic Plaques and Education Predicts Dementia

    PubMed Central

    Roe, Catherine M.; Xiong, Chengjie; Miller, J. Phillip; Cairns, Nigel J.; Morris, John C.

    2009-01-01

    In exploring the cognitive reserve hypothesis in persons with substantial Alzheimer disease neuropathology, we aimed to determine the extent to which educational attainment and densities of diffuse plaques, neuritic plaques, and neurofibrillary tangles predict dementia. Participants were 1563 individuals aged 65 years or above who were assessed for dementia within 1 year of death. Generalized linear mixed models were used to examine whether education and density ratings of diffuse plaques and neuritic plaques, and neurofibrillary tangle stage were associated with a dementia diagnosis. Education interacted with densities of neuritic plaques to predict dementia. Tangle density independently predicted dementia, but did not interact with education. Diffuse plaque density was unrelated to dementia when adjusted for densities of neuritic plaques and tangles. Among individuals with Alzheimer disease neuropathology, educational attainment, as a surrogate of cognitive reserve, modifies the influence of neuritic, but not diffuse, plaque neuropathology on the expression of dementia. PMID:18525294

  17. Immunization Program

    Science.gov Websites

    Department home page Immunizations Search: Search Toggle navigation Medical Services Disease Control Facebook Contacts CoverageRates Diseases Immunization Homepage Immunization Honor Roll HPV NDIIS Medical Providers

  18. Selective Neurodegeneration, Without Neurofibrillary Tangles, in a Mouse Model of Niemann-Pick C Disease

    PubMed Central

    German, Dwight C.; Quintero, E. Matthew; Liang, Chang-Lin; Ng, Benton; Punia, Surender; Xie, Chonglun; Dietschy, John M.

    2012-01-01

    The BALB/c mouse model of Niemann-Pick type C (NPC) disease exhibits neuropathological similarities to the human condition. There is an age-related cerebral atrophy, demyelination of the corpus callosum, and degeneration of cerebellar Purkinje cells in the NPC mouse. In human NPC, many cortical and subcortical neurons contain neurofibrillary tangles, which are thought by some investigators to play an important role in the neurodegenerative process. The purpose of the present study was to determine whether neurodegeneration occurs in the NPC mouse, in brain regions other than the cerebellum and whether the degeneration is related to the presence of neurofibrillary tangles. Using light microscopic methods with immunohistochemistry, electron microscopy, and cell counting methods, 11-week-old NPC+/+ and NPC−/− animals were examined. In the NPC−/− mice, there were 96% fewer Purkinje cells, 28% fewer neurons in the prefrontal cortex, 20% fewer neurons in the thalamus, and 63% fewer glial cells in the corpus callosum. On the other hand, previous studies indicate normal numbers of neurons and glial cells in these same neuroanatomical regions in young NPC−/− mice. There were normal numbers of cholinergic neurons in sections assessed in the striatum and basal forebrain in the 11-week-old animals and no evidence of neurofibrillary tangles within cells. The present data indicate that both neurons and glial cells die in the NPC mouse but that all cells are not equally vulnerable. There was no evidence for neurofibrillary tangles in the NPC mouse, and therefore the degenerative process in the mouse is unrelated to the neurofibrillary tangle. PMID:11298365

  19. Reconnection Dynamics and Mutual Friction in Quantum Turbulence

    NASA Astrophysics Data System (ADS)

    Laurie, Jason; Baggaley, Andrew W.

    2015-07-01

    We investigate the behaviour of the mutual friction force in finite temperature quantum turbulence in He, paying particular attention to the role of quantized vortex reconnections. Through the use of the vortex filament model, we produce three experimentally relevant types of vortex tangles in steady-state conditions, and examine through statistical analysis, how local properties of the tangle influence the mutual friction force. Finally, by monitoring reconnection events, we present evidence to indicate that vortex reconnections are the dominant mechanism for producing areas of high curvature and velocity leading to regions of high mutual friction, particularly for homogeneous and isotropic vortex tangles.

  20. Protease inhibitors and indoleamines selectively inhibit cholinesterases in the histopathologic structures of Alzheimer disease.

    PubMed Central

    Wright, C I; Guela, C; Mesulam, M M

    1993-01-01

    Neurofibrillary tangles and amyloid plaques express acetylcholinesterase and butyrylcholinesterase activity in Alzheimer disease. We previously reported that traditional acetylcholinesterase inhibitors such as BW284C51, tacrine, and physostigmine were more potent inhibitors of the acetylcholinesterase in normal axons and cell bodies than of the acetylcholinesterase in plaques and tangles. We now report that the reverse pattern is seen with indoleamines (such as serotonin and its precursor 5-hydroxytryptophan), carboxypeptidase inhibitor, and the nonspecific protease inhibitor bacitracin. These substances are more potent inhibitors of the cholinesterases in plaques and tangles than of those in normal axons and cell bodies. These results show that the enzymatic properties of plaque and tangle-associated cholinesterases diverge from those of normal axons and cell bodies. The selective susceptibility to bacitracin and carboxypeptidase inhibitor indicates that the catalytic sites of plaque and tangle-bound cholinesterases are more closely associated with peptidase or protease-like properties than the catalytic sites of cholinesterases in normal axons and cell bodies. This shift in enzymatic affinity may lead to the abnormal protein processing that is thought to play a major role in the pathogenesis of Alzheimer disease. The availability of pharmacological and dietary means for altering brain indoleamines raises therapeutic possibilities for inhibiting the abnormal cholinesterase activity associated with Alzheimer disease. Images PMID:8421706

  1. Spinal Infections

    MedlinePlus

    Toggle navigation CONDITIONS Low Back Pain Acute Low Back Pain Chronic Low Back Pain SI Joint Pain Other Scoliosis Back Pain and Emotional Distress Muscle Spasms Pinched Nerve Discitis Degenerative Conditions Bulge vs ...

  2. Inclusion and Diversity | NREL

    Science.gov Websites

    deep-seeded belief held by our leadership team. Listen to NREL Director Martin Keller share his . Toggle navigation Overall Senior Leadership Research Management Research Staff Postdocs & Interns

  3. Behind the curtain of tauopathy: a show of multiple players orchestrating tau toxicity.

    PubMed

    Huang, Yunpeng; Wu, Zhihao; Zhou, Bing

    2016-01-01

    tau, a microtubule-associated protein, directly binds with microtubules to dynamically regulate the organization of cellular cytoskeletons, and is especially abundant in neurons of the central nervous system. Under disease conditions such as Pick's disease, progressive supranuclear palsy, frontotemporal dementia, parkinsonism linked to chromosome 17 and Alzheimer's disease, tau proteins can self-assemble to paired helical filaments progressing to neurofibrillary tangles. In these diseases, collectively referred to as "tauopathies", alterations of diverse tau modifications including phosphorylation, metal ion binding, glycosylation, as well as structural changes of tau proteins have all been observed, indicating the complexity and variability of factors in the regulation of tau toxicity. Here, we review our current knowledge and hypotheses from relevant studies on tau toxicity, emphasizing the roles of phosphorylations, metal ions, folding and clearance control underlining tau etiology and their regulations. A summary of clinical efforts and associated findings of drug candidates under development is also presented. It is hoped that a more comprehensive understanding of tau regulation will provide us with a better blueprint of tau networking in neuronal cells and offer hints for the design of more efficient strategies to tackle tau-related diseases in the future.

  4. A new TAO kinase inhibitor reduces tau phosphorylation at sites associated with neurodegeneration in human tauopathies.

    PubMed

    Giacomini, Caterina; Koo, Chuay-Yeng; Yankova, Natalia; Tavares, Ignatius A; Wray, Selina; Noble, Wendy; Hanger, Diane P; Morris, Jonathan D H

    2018-05-07

    In Alzheimer's disease (AD) and related tauopathies, the microtubule-associated protein tau is highly phosphorylated and aggregates to form neurofibrillary tangles that are characteristic of these neurodegenerative diseases. Our previous work has demonstrated that the thousand-and-one amino acid kinases (TAOKs) 1 and 2 phosphorylate tau on more than 40 residues in vitro. Here we show that TAOKs are phosphorylated and active in AD brain sections displaying mild (Braak stage II), intermediate (Braak stage IV) and advanced (Braak stage VI) tau pathology and that active TAOKs co-localise with both pre-tangle and tangle structures. TAOK activity is also enriched in pathological tau containing sarkosyl-insoluble extracts prepared from AD brain. Two new phosphorylated tau residues (T123 and T427) were identified in AD brain, which appear to be targeted specifically by TAOKs. A new small molecule TAOK inhibitor (Compound 43) reduced tau phosphorylation on T123 and T427 and also on additional pathological sites (S262/S356 and S202/T205/S208) in vitro and in cell models. The TAOK inhibitor also decreased tau phosphorylation in differentiated primary cortical neurons without affecting markers of synapse and neuron health. Notably, TAOK activity also co-localised with tangles in post-mortem frontotemporal lobar degeneration (FTLD) brain tissue. Furthermore, the TAOK inhibitor decreased tau phosphorylation in induced pluripotent stem cell derived neurons from FTLD patients, as well as cortical neurons from a transgenic mouse model of tauopathy (Tau35 mice). Our results demonstrate that abnormal TAOK activity is present at pre-tangles and tangles in tauopathies and that TAOK inhibition effectively decreases tau phosphorylation on pathological sites. Thus, TAOKs may represent a novel target to reduce or prevent tau-associated neurodegeneration in tauopathies.

  5. Sore Throats

    MedlinePlus

    ... Marketplace ENT Careers Marketplace Log in b Search form Log in Toggle navigation b Join Now Donate ... matter in the air from the burning of fossil fuels, as well as common household chemicals, can ...

  6. Molecular and Genetic Investigation of Tau in Chronic Traumatic Encephalopthy

    DTIC Science & Technology

    2016-10-01

    Very wide blood vessels, but no gliosis, macrophages, or tangles. 6 Controls Heavy retraction around vessels and high amounts of cell shrinkage...neocortical pyramidal neuron. (B) This neuron contains a mature intracellular tangle. (C) In the white matter, scattered small granular retraction balls

  7. Stability of knotted vortices in wave chaos

    NASA Astrophysics Data System (ADS)

    Taylor, Alexander; Dennis, Mark

    Large scale tangles of disordered filaments occur in many diverse physical systems, from turbulent superfluids to optical volume speckle to liquid crystal phases. They can exhibit particular large scale random statistics despite very different local physics. We have previously used the topological statistics of knotting and linking to characterise the large scale tangling, using the vortices of three-dimensional wave chaos as a universal model system whose physical lengthscales are set only by the wavelength. Unlike geometrical quantities, the statistics of knotting depend strongly on the physical system and boundary conditions. Although knotting patterns characterise different systems, the topology of vortices is highly unstable to perturbation, under which they may reconnect with one another. In systems of constructed knots, these reconnections generally rapidly destroy the knot, but for vortex tangles the topological statistics must be stable. Using large scale simulations of chaotic eigenfunctions, we numerically investigate the prevalence and impact of reconnection events, and their effect on the topology of the tangle.

  8. Lumbar (Open) Microscopic Discectomy

    MedlinePlus

    Toggle navigation CONDITIONS Low Back Pain Acute Low Back Pain Chronic Low Back Pain SI Joint Pain Other Scoliosis Back Pain and Emotional Distress Muscle Spasms Pinched Nerve Discitis Degenerative Conditions Bulge vs ...

  9. Down Syndrome: Education

    MedlinePlus

    ... content Toggle navigation Home Our Story Mission Say Hello to Our Team Financial Information NDSS History About ... Events Shop NDSS Home Our Story Mission Say Hello to Our Team Financial Information NDSS History About ...

  10. NCIS publicdefault

    Science.gov Websites

    SERVICE SUBMIT A TIP CONNECT Facebook Logo Twitter Logo YouTube Logo Toggle navigation ABOUT NCIS MISSION Twitter Logo YouTube Logo CONNECT Privacy Policy Notice | Diversity Policy | Accessibility/Section 508

  11. Alzheimer's disease: neuritic plaques and neurofibrillary tangles in human brain identified by FTIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Choo, Lin-P'ing; Jackson, Michael; Halliday, William C.; Mantsch, Henry H.

    1994-01-01

    The abnormal abundance of (beta) -amyloid plaques and neurofibrillary tangles are the hallmark of Alzheimer's disease (AD). Human central nervous system (CNS) grey matter was probed for characteristics arising from these pathological features. In AD but not normal grey matter, an IR band at 1615 cm-1 is seen, characteristic of a protein in an aggregated state. We speculate that this band arises from (beta) A4-amyloid protein. AD, and 18q- grey matter spectra show increased intensity of phosphate bands in accordance with known hyperphosphorylation of proteins found in neurofibrillary tangles. These spectral features may be useful in the diagnosis of AD.

  12. Types of Stem Cells

    MedlinePlus

    ... Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

  13. Learn About Stem Cells

    MedlinePlus

    ... Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... Home > Learn About Stem Cells > Stem Cell Basics Cells in the human body The human body comprises ...

  14. Retrospective evaluation of milk production and culling risk following either surgical, toggle-pin suture or conservative treatment of left displaced abomasum in Chilean dairy cows.

    PubMed

    Melendez, P; Romero, C; Pithua, P; Marin, M P; Pinedo, P; Duchens, M

    2017-11-01

    AIMS To describe milk yield and culling risk in cows diagnosed with left displacement of abomasum (LDA) treated either conservatively, by right flank pyloric omentopexy, or rolling and toggling, compared with normal herdmates from four Chilean dairy herds. METHODS Historical records were obtained from four commercial dairy farms located in Central Chile for cows with a history of LDA between 2010 and 2012, and healthy herdmates. Cows with LDA were categorised into three groups: cows treated with right omentopexy (ST, n=58), cows treated by toggle suturing (TT, n=15) and cows treated conservatively (CT, n=56). Control cows (n=129) were selected from unaffected cows, matched by days in milk (DIM), parity and herd with affected cows. Groups were compared for risk of culling up to 300 DIM and for milk production up to 5 months of lactation using survival and Cox proportional hazard models and mixed models for repeated measures, respectively. RESULTS Compared with cows in the Control group, the risk of being culled up to 300 DIM was 9.1 (SE 0.62) times greater in ST cows, 10.4 (SE 0.68) times greater in TT cows, and 37.3 (SE 0.61) times greater in CT cows (p<0.01). In the first 5 months of lactation, compared with cows in the Control group, mean daily milk production was 23.3 (SE 1.5) kg less in ST cows, 15.3 (SE 1.6) kg less in TT cows, and 30.1 (SE 1.3) kg less in CT cows (p<0.001). CONCLUSIONS AND CLINICAL RELEVANCE Cows in four dairy herds in central Chile diagnosed and treated for LDA produced significantly less milk and had a higher risk of culling than healthy herdmates. Although cows treated surgically or with toggle suture never recovered to the extent of healthy cows, they produced more milk than cows treated conservatively. However, the retrospective nature of the data, the inclusion of only four herds and the non-random allocation to treatments means that these conclusions cannot be extrapolated to the overall dairy cattle population in Chile.

  15. Tangled Threads: Mentoring within a Community of Practice

    ERIC Educational Resources Information Center

    Tarr, Patricia

    2010-01-01

    Tangled Threads, a case study of a group of women art educators, examines the nature of mentoring relationships within the context of a professional association. Grounded in literature on "community of practice," relational and peer mentoring, and an ethic of care, the study uncovers the complex interconnections between women's professional and…

  16. Down Syndrome: Co-Occuring Conditions

    MedlinePlus

    ... content Toggle navigation Home Our Story Mission Say Hello to Our Team Financial Information NDSS History About ... Events Shop NDSS Home Our Story Mission Say Hello to Our Team Financial Information NDSS History About ...

  17. HubbleSite - Out of the ordinary...out of this world.

    Science.gov Websites

    Toggle navigation Home News Images Videos Blogs Explore Discoveries Astronomy Technology Education ! Email list: Inbox Astronomy Servicing Missions Reference Desk eBooks WebbTelescope Amazing Space

  18. Interstitial Cystitis Association

    MedlinePlus

    ... Donor Resources My Profile Login Social Media Twitter YouTube Facebook Pinterest Community ShareThis Google Search Toggle navigation ... Resources for Donors Corporate Contributions Social Media Twitter YouTube Facebook Pinterest Community ShareThis Google Search Home About ...

  19. American Orthopaedic Society for Sports Medicine

    MedlinePlus

    ... Upcoming Meetings Online Education Archived Meetings Faculty Resources Sports Medicine Fellowships Traveling Fellowship Submit an Abstract Submit ... Support AOSSM Research Publications Toggle American Journal of Sports Medicine Sports Health: A Multidisciplinary Approach Orthopaedic Journal ...

  20. An electrically actuated molecular toggle switch

    NASA Astrophysics Data System (ADS)

    Gerhard, Lukas; Edelmann, Kevin; Homberg, Jan; Valášek, Michal; Bahoosh, Safa G.; Lukas, Maya; Pauly, Fabian; Mayor, Marcel; Wulfhekel, Wulf

    2017-03-01

    Molecular electronics is considered a promising approach for future nanoelectronic devices. In order that molecular junctions can be used as electrical switches or even memory devices, they need to be actuated between two distinct conductance states in a controlled and reproducible manner by external stimuli. Here we present a tripodal platform with a cantilever arm and a nitrile group at its end that is lifted from the surface. The formation of a coordinative bond between the nitrile nitrogen and the gold tip of a scanning tunnelling microscope can be controlled by both electrical and mechanical means, and leads to a hysteretic switching of the conductance of the junction by more than two orders of magnitude. This toggle switch can be actuated with high reproducibility so that the forces involved in the mechanical deformation of the molecular cantilever can be determined precisely with scanning tunnelling microscopy.

  1. Neuropil threads occur in dendrites of tangle-bearing nerve cells.

    PubMed

    Braak, H; Braak, E

    1988-01-01

    Transparent Golgi preparations counterstained for Alzheimer's neurofibrillary changes rendered possible the demonstration of neuropil threads in defined cellular processes. Only dendrites of tangle-bearing cortical nerve cells were found to contain neuropil threads. Processes of glial cells as well as axons present in the material were devoid of neuropil threads.

  2. Tangled Narratives and Wicked Problems: A Complex Case of Positioning and Politics in a Diverse School Community

    ERIC Educational Resources Information Center

    Nguyen, Thu Suong Thi; Scribner, Samantha M. Paredes; Crow, Gary M.

    2012-01-01

    The case of Allen Elementary School presents tangled narratives and wicked problems describing the multidimensionality of school community work. Using multiple converging and diverging vignettes, the case points to the distinctiveness of individual experience in schools; the ways institutionalized organizational narratives become cultural…

  3. Principal Facts for 463 Gravity Stations in the Vicinity of Tangle Lakes, East-Central Alaska

    USGS Publications Warehouse

    Morin, Robert L.; Glen, Jonathan M.G.

    2002-01-01

    During the summer of 2001, a gravity survey was conducted in the vicinity of Tangle Lakes, east-central Alaska. Measurements of 87 gravity stations were made. The Tangle Lakes area is located about 25 km west of Paxson and north of the Denali Highway. The gravity survey is located on the southwest corner of the Mt. Hayes and the northwest corner of the Gulkana 1:250,000 scale USGS topographic maps. The boundaries of the study area are 62 deg 30' to 63 deg 30' N. latitude and 145 deg 30' to 147 deg 00' W. longitude. A map showing the location of the study area is shown in figure 1. One gravity base station was used for control for this survey. This base station, TLIN is located at the Tangle Lakes Inn. The observed gravity of this station was calculated based on multiple ties to base stations ANCU in Anchorage, PALH in Palmer, BD27 in Gulkana, and base stations D42, and D57 along the Denali Highway.

  4. Symplectic homoclinic tangles of the ideal separatrix of the DIII-D from type I ELMs

    NASA Astrophysics Data System (ADS)

    Punjabi, Alkesh; Ali, Halima

    2012-10-01

    The ideal separatrix of the divertor tokamaks is a degenerate manifold where both the stable and unstable manifolds coincide. Non-axisymmetric magnetic perturbations remove the degeneracy; and split the separatrix manifold. This creates an extremely complex topological structure, called homoclinic tangles. The unstable manifold intersects the stable manifold and creates alternating inner and outer lobes at successive homoclinic points. The Hamiltonian system must preserve the symplectic topological invariance, and this controls the size and radial extent of the lobes. Very recently, lobes near the X-point have been experimentally observed in MAST [A. Kirk et al, PRL 108, 255003 (2012)]. We have used the DIII-D map [A. Punjabi, NF 49, 115020 (2009)] to calculate symplectic homoclinic tangles of the ideal separatrix of the DIII-D from the type I ELMs represented by the peeling-ballooning modes (m,n)=(30,10)+(40,10). The DIII-D map is symplectic, accurate, and is in natural canonical coordinates which are invertible to physical coordinates [A. Punjabi and H. Ali, POP 15, 122502 (2008)]. To our knowledge, we are the first to symplectically calculate these tangles in physical space. Homoclinic tangles of separatrix can cause radial displacement of mobile passing electrons and create sheared radial electric fields and currents, resulting in radial flows, drifts, differential spinning, and reduction in turbulence, and other effects. This work is supported by the grants DE-FG02-01ER54624 and DE-FG02-04ER54793.

  5. Amyloid mediates the association of apolipoprotein E e4 allele to cognitive function in older people

    PubMed Central

    Bennett, D; Schneider, J; Wilson, R; Bienias, J; Berry-Kravis, E; Arnold, S

    2005-01-01

    Background: The neurobiological changes underlying the association of the apolipoprotein E (APOE) e4 allele with level of cognition are poorly understood. Objective: To test the hypothesis that amyloid load can account for (mediate) the association of the APOE e4 allele with level of cognition assessed proximate to death. Methods: There were 44 subjects with clinically diagnosed Alzheimer's disease and 50 without dementia, who had participated in the Religious Orders Study. They underwent determination of APOE allele status, had comprehensive cognitive testing in the last year of life, and brain autopsy at death. The percentage area of cortex occupied by amyloid beta and the density of tau positive neurofibrillary tangles were quantified from six brain regions and averaged to yield summary measures of amyloid load and neurofibrillary tangles. Multiple regression analyses were used to examine whether amyloid load could account for the effect of allele status on level of cognition, controlling for age, sex, and education. Results: Possession of at least one APOE e4 allele was associated with lower level of cognitive function proximate to death (p = 0.04). The effect of the e4 allele was reduced by nearly 60% and was no longer significant after controlling for the effect of amyloid load, whereas there was a robust inverse association between amyloid and cognition (p = 0.001). Because prior work had suggested that neurofibrillary tangles could account for the association of amyloid on cognition, we next examined whether amyloid could account for the effect of allele status on tangles. In a series of regression analyses, e4 was associated with density of tangles (p = 0.002), but the effect of the e4 allele was reduced by more than 50% and was no longer significant after controlling for the effect of amyloid load. Conclusion: These findings are consistent with a sequence of events whereby the e4 allele works through amyloid deposition and subsequent tangle formation to cause cognitive impairment. PMID:16107349

  6. Nine Things to Know About Stem Cell Treatments

    MedlinePlus

    ... Toggle Nav Nine Things To Know About Stem Cell Treatments Home > Stem Cells and Medicine > Nine Things ... About Stem Cell Treatments Many clinics offering stem cell treatments make claims that are not supported by ...

  7. Accelerated Cure Project for Multiple Sclerosis

    MedlinePlus

    ... main content Accelerating research toward a cure for multiple sclerosis Toggle navigation Search form Search Connect Volunteer Donate ... is to accelerate efforts toward a cure for multiple sclerosis by rapidly advancing research that determines its causes ...

  8. Capacitive Trans-Impedance Amplifier Circuit with Charge Injection Compensation

    NASA Technical Reports Server (NTRS)

    Milkov, Mihail M. (Inventor); Gulbransen, David J. (Inventor)

    2016-01-01

    A capacitive trans-impedance amplifier circuit with charge injection compensation is provided. A feedback capacitor is connected between an inverting input port and an output port of an amplifier. A MOS reset switch has source and drain terminals connected between the inverting input and output ports of the amplifier, and a gate terminal controlled by a reset signal. The reset switch is open or inactive during an integration phase, and closed or active to electrically connect the inverting input port and output port of the amplifier during a reset phase. One or more compensation capacitors are provided that are not implemented as gate oxide or MOS capacitors. Each compensation capacitor has a first port connected to a compensation signal that is a static signal or a toggling compensation signal that toggles between two compensation voltage values, and a second port connected to the inverting input port of the amplifier.

  9. Tangled Hierarchies: Teachers as Professionals and the Management of School. The Jossey-Bass Education Series.

    ERIC Educational Resources Information Center

    Shedd, Joseph B.; Bacharach, Samuel B.

    Teachers need flexibility to adapt to the uncertain situations and unique needs they confront in their classrooms. Most efforts to reform public education address the needs of teachers at the expense of administration--and vice versa--reinforcing the tangled relationships and patterns of compromise and conflict they are meant to solve. This book…

  10. Analysis of the effect of attachment point bias during large space debris removal using a tethered space tug

    NASA Astrophysics Data System (ADS)

    Chu, Zhongyi; Di, Jingnan; Cui, Jing

    2017-10-01

    Space debris occupies a valuable orbital resource and is an inevitable and urgent problem, especially for large space debris because of its high risk and the possible crippling effects of a collision. Space debris has attracted much attention in recent years. A tethered system used in an active debris removal scenario is a promising method to de-orbit large debris in a safe manner. In a tethered system, the flexibility of the tether used in debris removal can possibly induce tangling, which is dangerous and should be avoided. In particular, attachment point bias due to capture error can significantly affect the motion of debris relative to the tether and increase the tangling risk. Hence, in this paper, the effect of attachment point bias on the tethered system is studied based on a dynamic model established based on a Newtonian approach. Next, a safety metric of avoiding a tangle when a tether is tensioned with attachment point bias is designed to analyse the tangling risk of the tethered system. Finally, several numerical cases are established and simulated to validate the effects of attachment point bias on a space tethered system.

  11. Habits and customs of crab catchers in southern Bahia, Brazil.

    PubMed

    Firmo, Angélica M S; Tognella, Mônica M P; Tenório, Gabrielle D; Barboza, Raynner R D; Alves, Rômulo R N

    2017-08-23

    Brazilian mangrove forests are widely distributed along the coast and exploited by groups of people with customs and habits as diverse as the biology of the mangrove ecosystems. This study identifies different methods of extracting crabs that inhabit the mangrove belts; some of these activities, such as catching individual crabs by hand, are aimed at maintaining natural stocks of this species in Mucuri (south Bahia), Brazil. In the studied community, illegal hunting activities that violate Brazilian legislation limiting the use of tangle-netting in mangrove ecosystem were observed. According to our observations, fishermen, to catch individual crabs, use the tangle-netting technique seeking to increase income and are from families that have no tradition of extraction. This analysis leads us to conclude that catchers from economically marginalised social groups enter mangroves for purposes of survival rather than for purposes of subsistence, because the catching by tangle-netting is a predatory technique. Tangle-netting  technique increase caught but also increases their mortality rate. We emphasise that traditional catching methods are unique to Brazil and that manual capturing of crab should be preserved through public policies aimed at maintaining the crab population.

  12. Optical Coherence Tomography Angiography Reveals Mature, Tangled Vascular Networks in Eyes With Neovascular Age-Related Macular Degeneration Showing Resistance to Geographic Atrophy.

    PubMed

    Dansingani, Kunal K; Freund, K Bailey

    2015-10-01

    To demonstrate a vascular pattern seen on optical coherence tomography angiography (OCTA) that appears to correlate with reduced rates of geographic atrophy (GA) in eyes receiving long-term anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (AMD). Non-consecutive, retrospective cohort study. Patients were included if they had received more than 50 anti-VEGF injections during a period of at least 4 years for neovascular AMD in at least one eye, with absence or minimal progression of GA. Clinical charts and imaging were reviewed retrospectively; study eyes underwent OCTA. Nine eyes of eight patients were included. Mean age was 82 years, and mean follow-up of study eyes 9.1 years; study eyes received a mean of 65.8 injections. OCTA revealed tangled networks of neovessels associated with type 1 lesions. With prolonged anti-VEGF treatment, GA appears to occur less commonly in eyes with type 1 neovascularization. OCTA shows mature tangled vessels with substantial flow within type 1 lesions. Mature, tangled networks may be associated with a decreased likelihood of developing GA despite the presence of choriocapillaris atrophy. Copyright 2015, SLACK Incorporated.

  13. Website Policies / Important Links | DOepatents

    Science.gov Websites

    Global to push GA events into Global to push GA events into skip to main content PATENTS Toggle Science Resources: SciTech Connect DOE PAGES More DOE Collections » U.S. / Global Science Resources

  14. Videos | NOAA Gulf Spill Restoration

    Science.gov Websites

    Skip to main content Home Home Toggle navigation Search form Search Search the web Search NOAA Gulf Spill Restoration Search Home About Us Trustees Contact Us How We Restore Planning Damage Assessment

  15. Homoclinic tangle of the ideal separatrix in the DIII-D tokamak from (30, 10) + (40, 10) perturbation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Punjabi, Alkesh

    Trajectories of magnetic field lines are a 1½ degree of freedom Hamiltonian system. The perturbed separatrix in a divertor tokamak is radically different from the unperturbed one. This is because magnetic asymmetries cause the separatrix to form extremely complicated structures called homoclinic tangles. The shape of flux surfaces in the edge region of divertor tokamaks such as the DIII (J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)) is fundamentally different from near-circular. Recently, a new method is developed to calculate the homoclinic tangle and lobes of the separatrix of divertor tokamaks in physical space (A. Punjabimore » and A. Boozer, Phys. Lett. A 378, 2410 (2014)). This method is based on three elements: preservation of the two invariants—symplectic and topological neighborhood—and a new set of canonical coordinates called the natural canonical coordinates. The very complicated shape of edge surfaces can be represented very accurately and very realistically in these new coordinates (A. Punjabi and H. Ali, Phys. Plasmas 15, 122502 (2008); A. Punjabi, Nucl. Fusion 49, 115020 (2009)). A symplectic map in the new coordinates can advance the separatrix manifold forward and backward in time. Every time the two manifolds meet in a fixed poloidal plane, they intersect and form homoclinic tangle to preserve the two invariants. The new coordinates can be mapped to physical space and the dynamical evolution of the homoclinic tangle can be seen and pictured in physical space. Here, the new method is applied to the DIII-D tokamak to study the basic features of the homoclinic tangle of the unperturbed separatrix from two Fourier components, which represent the peeling-ballooning modes of equal amplitude and no radial dependence, and the results are analyzed. Homoclinic tangle has a very complicated structure and becomes extremely complicated for as the lines take more toroidal turns, especially near the X-point. Homoclinic tangle is the most complicated near the X-point and forms the largest lobes there. On average, the field lines cover a distance of about 9 m per turn. Poloidal rotation of the lines has large gradients in the poloidal direction. The average normal displacement of the lines on the separatrix varies from 5 mm to 7 cm. Average outward displacement of the lines is considerably larger than the inward displacement; however, on the average more lines are displaced inside than outside of the separatrix. The field line diffusion normal to the separatrix has extremely wide variation and very large poloidal gradients. Half of all the lines are lost in less than 6 turns. Complicated electric potentials will be required to maintain the neutrality of the plasma, and the E × B drifts from these fields can modify plasma confinement and influence the edge physics (A. Punjabi and A. Boozer, Phys. Lett. A 378, 2410 (2014))« less

  16. Homoclinic tangle of the ideal separatrix in the DIII-D tokamak from (30, 10) + (40, 10) perturbation

    NASA Astrophysics Data System (ADS)

    Punjabi, Alkesh

    2014-12-01

    Trajectories of magnetic field lines are a 1½ degree of freedom Hamiltonian system. The perturbed separatrix in a divertor tokamak is radically different from the unperturbed one. This is because magnetic asymmetries cause the separatrix to form extremely complicated structures called homoclinic tangles. The shape of flux surfaces in the edge region of divertor tokamaks such as the DIII (J. L. Luxon and L. G. Davis, Fusion Technol. 8, 441 (1985)) is fundamentally different from near-circular. Recently, a new method is developed to calculate the homoclinic tangle and lobes of the separatrix of divertor tokamaks in physical space (A. Punjabi and A. Boozer, Phys. Lett. A 378, 2410 (2014)). This method is based on three elements: preservation of the two invariants—symplectic and topological neighborhood—and a new set of canonical coordinates called the natural canonical coordinates. The very complicated shape of edge surfaces can be represented very accurately and very realistically in these new coordinates (A. Punjabi and H. Ali, Phys. Plasmas 15, 122502 (2008); A. Punjabi, Nucl. Fusion 49, 115020 (2009)). A symplectic map in the new coordinates can advance the separatrix manifold forward and backward in time. Every time the two manifolds meet in a fixed poloidal plane, they intersect and form homoclinic tangle to preserve the two invariants. The new coordinates can be mapped to physical space and the dynamical evolution of the homoclinic tangle can be seen and pictured in physical space. Here, the new method is applied to the DIII-D tokamak to study the basic features of the homoclinic tangle of the unperturbed separatrix from two Fourier components, which represent the peeling-ballooning modes of equal amplitude and no radial dependence, and the results are analyzed. Homoclinic tangle has a very complicated structure and becomes extremely complicated for as the lines take more toroidal turns, especially near the X-point. Homoclinic tangle is the most complicated near the X-point and forms the largest lobes there. On average, the field lines cover a distance of about 9 m per turn. Poloidal rotation of the lines has large gradients in the poloidal direction. The average normal displacement of the lines on the separatrix varies from 5 mm to 7 cm. Average outward displacement of the lines is considerably larger than the inward displacement; however, on the average more lines are displaced inside than outside of the separatrix. The field line diffusion normal to the separatrix has extremely wide variation and very large poloidal gradients. Half of all the lines are lost in less than 6 turns. Complicated electric potentials will be required to maintain the neutrality of the plasma, and the E × B drifts from these fields can modify plasma confinement and influence the edge physics (A. Punjabi and A. Boozer, Phys. Lett. A 378, 2410 (2014)).

  17. Environmental Compliance | NOAA Gulf Spill Restoration

    Science.gov Websites

    Skip to main content Home Home Toggle navigation Search form Search Search the web Search NOAA Gulf Spill Restoration Search Home About Us Trustees Contact Us How We Restore Planning Damage Assessment

  18. Rapid Neurofibrillary Tangle Formation after Localized Gene Transfer of Mutated Tau

    PubMed Central

    Klein, Ronald L.; Lin, Wen-Lang; Dickson, Dennis W.; Lewis, Jada; Hutton, Michael; Duff, Karen; Meyer, Edwin M.; King, Michael A.

    2004-01-01

    Neurofibrillary pathology was produced in the brains of adult rats after localized gene transfer of human tau carrying the P301L mutation, which is associated with frontotemporal dementia with parkinsonism. Within 1 month of in situ transfection of the basal forebrain region of normal rats, tau-immunoreactive and argyrophilic neuronal lesions formed. The fibrillar lesions had features of neurofibrillary tangles and tau immunoreactivity at light and electron microscopic levels. In addition to neurofibrillary tangles, other tau pathology, including pretangles and neuropil threads, was abundant and widespread. Tau gene transfer to the hippocampal region of amyloid-depositing transgenic mice produced pretangles and threads, as well as intensely tau-immunoreactive neurites in amyloid plaques. The ability to produce neurofibrillary pathology in adult rodents makes this a useful method to study tau-related neurodegeneration. PMID:14695347

  19. Quick action clamp

    NASA Technical Reports Server (NTRS)

    Calco, Frank S. (Inventor)

    1991-01-01

    A quick release toggle clamp that utilizes a spring that requires a deliberate positive action for disengagement is presented. The clamp has a sliding bolt that provides a latching mechanism. The bolt is moved by a handle that tends to remain in an engaged position while under tension.

  20. IARC - Illinois Accelerator Research Center | Pilot Program

    Science.gov Websites

    Toggle navigation Pilot Program Agenda Directions Registration Illinois Accelerator Research Center National Laboratory present Accelerator Stewardship Test Facility Pilot Program Use accelerator technology , energy and environment. With this pilot program, the DOE Office of Science National Laboratories are

  1. Design, synthesis and biological evaluation of trimethine cyanine dyes as fluorescent probes for the detection of tau fibrils in Alzheimer's disease brain and olfactory epithelium.

    PubMed

    Gu, Jiamin; Anumala, Upendra Rao; Heyny-von Haußen, Roland; Hölzer, Jana; Goetschy-Meyer, Valérie; Mall, Gerhard; Hilger, Ingrid; Czech, Christian; Schmidt, Boris

    2013-06-01

    Shedding light on grey matter: Fluorescent trimethine cyanines were evaluated as imaging probes for neurofibrillary tangles in post-mortem brain sections of Alzheimer's disease patients. These probes bind to neurofibrillary tangles with high contrast and selectivity over amyloid β plaques. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Materials for Adaptive Structural Acoustic Control. Volume 1

    DTIC Science & Technology

    1993-04-06

    FOLLOWING PAGE 14. SUBJECT TERMS 15. NUMBER OF PAGES 16. PRICE CODE 17. SECURITY CLASSIFICATION 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION 20...375 Rubber is a highly nonlinear clastic medium. In the unstressed compliant state, the molecules ate coiled and tangled . but under stress the molecules...one-dimensional system, \\\\here tangle (solid dots) and the oblique (open circle) states are the shaded area represents the level of thermal energy

  3. Effect of Spinal Manipulation of Upper Cervical Vertebrae on Blood Pressure: Results of a Pilot Sham-Controlled Trial.

    PubMed

    Goertz, Christine M; Salsbury, Stacie A; Vining, Robert D; Long, Cynthia R; Pohlman, Katherine A; Weeks, William B; Lamas, Gervasio A

    2016-06-01

    The purpose of this pilot sham-controlled clinical trial was to estimate the treatment effect and safety of toggle recoil spinal manipulation for blood pressure management. Fifty-one participants with prehypertension or stage 1 hypertension (systolic blood pressure ranging from 135 to 159 mm Hg or diastolic blood pressure ranging from 85 to 99 mm Hg) were allocated by an adaptive design to 2 treatments: toggle recoil spinal manipulation or a sham procedure. Participants were seen by a doctor of chiropractic twice weekly for 6 weeks and remained on their antihypertensive medications, as prescribed, throughout the trial. Blood pressure was assessed at baseline and after study visits 1, 6 (week 3), and 12 (week 6), with the primary end point at week 6. Analysis of covariance was used to compare mean blood pressure changes from baseline between groups at each end point, controlling for sex, age, body mass index, and baseline blood pressure. Adjusted mean change from baseline to week 6 was greater in the sham group (systolic, -4.2 mm Hg; diastolic, -1.6 mm Hg) than in the spinal manipulation group (systolic, 0.6 mm Hg; diastolic, 0.7 mm Hg), but the difference was not statistically significant. No serious and few adverse events were noted. Six weeks of toggle recoil spinal manipulation did not lower systolic or diastolic blood pressure when compared with a sham procedure. No serious adverse events from either treatment were reported. Our results do not support a larger clinical trial. Further research to understand the potential mechanisms of action involving upper cervical manipulation on blood pressure is warranted before additional clinical investigations are conducted. Copyright © 2016. Published by Elsevier Inc.

  4. Division of Agriculture

    Science.gov Websites

    Department of Natural Resources logo, color scheme Department of Natural Resources Division of Agriculture Search Search DNR's site DNR State of Alaska Toggle main menu visibility Agriculture Home Programs Asset Disposals Alaska Caps Progam Board of Agriculture & Conservation Farm To School Program Grants

  5. DIRECT operational field test evaluation natural use study. Part 4, Recommendations for expanded deployment

    DOT National Transportation Integrated Search

    1998-08-01

    The DIRECT project compared four low-cost driver information systems. Of the four that were : compared, the RDS approach proved superior to the others in toggling reliability and voice quality. The DIRECT project planned to expand the implementation ...

  6. Mojave Desert Ecosystem Program

    Science.gov Websites

    Toggle navigation logo garis Home About Search Contact About Us History The Mojave Desert Ecosystem providing dynamic, sustainable, land management decision-making at the ecosystem level. Its numerous mission of the Mojave Desert Ecosystem Program is to provide government agencies throughout the Mojave

  7. Determination of capacity of single-toggle jaw crusher, taking into account parameters of kinematics of its working mechanism

    NASA Astrophysics Data System (ADS)

    Golikov, N. S.; Timofeev, I. P.

    2018-05-01

    Efficiency increase of jaw crushers makes the foundation of rational kinematics and stiffening of the elements of the machine possible. Foundation of rational kinematics includes establishment of connection between operation mode parameters of the crusher and its technical characteristics. The main purpose of this research is just to establish such a connection. Therefore this article shows analytical procedure of getting connection between operation mode parameters of the crusher and its capacity. Theoretical, empirical and semi-empirical methods of capacity determination of a single-toggle jaw crusher are given, taking into account physico-mechanical properties of crushed material and kinematics of the working mechanism. When developing a mathematical model, the method of closed vector polygons by V. A. Zinoviev was used. The expressions obtained in the article give an opportunity to solve important scientific and technical problems, connected with finding the rational kinematics of the jaw crusher mechanism, carrying out a comparative assessment of different crushers and giving the recommendations about updating the available jaw crushers.

  8. Multi-scale kinetics of a field-directed colloidal phase transition.

    PubMed

    Swan, James W; Vasquez, Paula A; Whitson, Peggy A; Fincke, E Michael; Wakata, Koichi; Magnus, Sandra H; De Winne, Frank; Barratt, Michael R; Agui, Juan H; Green, Robert D; Hall, Nancy R; Bohman, Donna Y; Bunnell, Charles T; Gast, Alice P; Furst, Eric M

    2012-10-02

    Polarizable colloids are expected to form crystalline equilibrium phases when exposed to a steady, uniform field. However, when colloids become localized this field-induced phase transition arrests and the suspension persists indefinitely as a kinetically trapped, percolated structure. We anneal such gels formed from magneto-rheological fluids by toggling the field strength at varied frequencies. This processing allows the arrested structure to relax periodically to equilibrium--colloid-rich, cylindrical columns. Two distinct growth regimes are observed: one in which particle domains ripen through diffusive relaxation of the gel, and the other where the system-spanning structure collapses and columnar domains coalesce apparently through field-driven interactions. There is a stark boundary as a function of magnetic field strength and toggle frequency distinguishing the two regimes. These results demonstrate how kinetic barriers to a colloidal phase transition are subverted through measured, periodic variation of driving forces. Such directed assembly may be harnessed to create unique materials from dispersions of colloids.

  9. Neuropathological Alterations in Alzheimer Disease

    PubMed Central

    Serrano-Pozo, Alberto; Frosch, Matthew P.; Masliah, Eliezer; Hyman, Bradley T.

    2011-01-01

    The neuropathological hallmarks of Alzheimer disease (AD) include “positive” lesions such as amyloid plaques and cerebral amyloid angiopathy, neurofibrillary tangles, and glial responses, and “negative” lesions such as neuronal and synaptic loss. Despite their inherently cross-sectional nature, postmortem studies have enabled the staging of the progression of both amyloid and tangle pathologies, and, consequently, the development of diagnostic criteria that are now used worldwide. In addition, clinicopathological correlation studies have been crucial to generate hypotheses about the pathophysiology of the disease, by establishing that there is a continuum between “normal” aging and AD dementia, and that the amyloid plaque build-up occurs primarily before the onset of cognitive deficits, while neurofibrillary tangles, neuron loss, and particularly synaptic loss, parallel the progression of cognitive decline. Importantly, these cross-sectional neuropathological data have been largely validated by longitudinal in vivo studies using modern imaging biomarkers such as amyloid PET and volumetric MRI. PMID:22229116

  10. Ultrastructural localization of acetylcholinesterase in neurofibrillary tangles, neuropil threads and senile plaques in aged and Alzheimer's brain.

    PubMed

    Gomez-Ramos, P; Mufson, E J; Moran, M A

    1992-01-13

    Acetylcholinesterase (AChE) histochemistry was used to evaluate the accumulation of this enzyme in senile plaques, neurofibrillary tangles and neuropil threads using light and electron microscopy in Alzheimer's disease as well as non-demented aged brains. Under the electron microscope, a crystalline-like AChE precipitate was localized over paired helical filaments and straight filaments in both neurofibrillary tangles and neuropil threads. AChE reaction product also decorated the amyloid fibrils in diffuse plaques as well as the halo and the heavy accumulation of amyloid which forms the core of classical plaques. In both diffuse plaques and the halo of classical plaques, we found AChE-positive structures resembling cell processes, which in some cases appeared to contain amyloid fibrils. The possible origin and significance of AChE localized over paired helical filaments, straight filaments and amyloid is discussed.

  11. Ising Model on Tangled Chain, Some Thermodynamic Properties

    NASA Astrophysics Data System (ADS)

    Mejdani, R.

    1996-09-01

    In this paper we consider an Ising model on tangled chain, where some additional bonds compared to a pure Ising chain are presented. To understand the behavior of this system and the competition between ferromagnetic bonds J along the chain and antiferromagnetic bonds J' across the chain, we have studied in detail analytically and iteratively some of the thermodynamic quantities. Particularly interesting is, in the zero-field and zero-temperature limit, the behavior of the magnetization and the susceptibility closely related to the ground-state configurations and their degeneracies. This degeneracy, presented at the condition J' ≤ -J between J and J', explains, also, the existence of nonzero entropy at zero temperature. This model applied as a lattice gas model defined on a tangled chain could be also useful for the experimental investigations in studying the saturation curves for the enzyme kinetics or the melting curves for DNA-denaturation.

  12. Vortex knots in tangled quantum eigenfunctions

    PubMed Central

    Taylor, Alexander J.; Dennis, Mark R.

    2016-01-01

    Tangles of string typically become knotted, from macroscopic twine down to long-chain macromolecules such as DNA. Here, we demonstrate that knotting also occurs in quantum wavefunctions, where the tangled filaments are vortices (nodal lines/phase singularities). The probability that a vortex loop is knotted is found to increase with its length, and a wide gamut of knots from standard tabulations occur. The results follow from computer simulations of random superpositions of degenerate eigenstates of three simple quantum systems: a cube with periodic boundaries, the isotropic three-dimensional harmonic oscillator and the 3-sphere. In the latter two cases, vortex knots occur frequently, even in random eigenfunctions at relatively low energy, and are constrained by the spatial symmetries of the modes. The results suggest that knotted vortex structures are generic in complex three-dimensional wave systems, establishing a topological commonality between wave chaos, polymers and turbulent Bose–Einstein condensates. PMID:27468801

  13. Clinicopathologic and 11C-Pittsburgh compound B implications of Thal amyloid phase across the Alzheimer’s disease spectrum

    PubMed Central

    Lowe, Val J.; Graff-Radford, Neill R.; Liesinger, Amanda M.; Cannon, Ashley; Przybelski, Scott A.; Rawal, Bhupendra; Parisi, Joseph E.; Petersen, Ronald C.; Kantarci, Kejal; Ross, Owen A.; Duara, Ranjan; Knopman, David S.; Jack, Clifford R.; Dickson, Dennis W.

    2015-01-01

    Thal amyloid phase, which describes the pattern of progressive amyloid-β plaque deposition in Alzheimer’s disease, was incorporated into the latest National Institute of Ageing – Alzheimer’s Association neuropathologic assessment guidelines. Amyloid biomarkers (positron emission tomography and cerebrospinal fluid) were included in clinical diagnostic guidelines for Alzheimer’s disease dementia published by the National Institute of Ageing – Alzheimer’s Association and the International Work group. Our first goal was to evaluate the correspondence of Thal amyloid phase to Braak tangle stage and ante-mortem clinical characteristics in a large autopsy cohort. Second, we examined the relevance of Thal amyloid phase in a prospectively-followed autopsied cohort who underwent ante-mortem 11C-Pittsburgh compound B imaging; using the large autopsy cohort to broaden our perspective of 11C-Pittsburgh compound B results. The Mayo Clinic Jacksonville Brain Bank case series (n = 3618) was selected regardless of ante-mortem clinical diagnosis and neuropathologic co-morbidities, and all assigned Thal amyloid phase and Braak tangle stage using thioflavin-S fluorescent microscopy. 11C-Pittsburgh compound B studies from Mayo Clinic Rochester were available for 35 participants scanned within 2 years of death. Cortical 11C-Pittsburgh compound B values were calculated as a standard uptake value ratio normalized to cerebellum grey/white matter. In the high likelihood Alzheimer’s disease brain bank cohort (n = 1375), cases with lower Thal amyloid phases were older at death, had a lower Braak tangle stage, and were less frequently APOE-ε4 positive. Regression modelling in these Alzheimer’s disease cases, showed that Braak tangle stage, but not Thal amyloid phase predicted age at onset, disease duration, and final Mini-Mental State Examination score. In contrast, Thal amyloid phase, but not Braak tangle stage or cerebral amyloid angiopathy predicted 11C-Pittsburgh compound B standard uptake value ratio. In the 35 cases with ante-mortem amyloid imaging, a transition between Thal amyloid phases 1 to 2 seemed to correspond to 11C-Pittsburgh compound B standard uptake value ratio of 1.4, which when using our pipeline is the cut-off point for detection of clear amyloid-positivity regardless of clinical diagnosis. Alzheimer’s disease cases who were older and were APOE-ε4 negative tended to have lower amyloid phases. Although Thal amyloid phase predicted clinical characteristics of Alzheimer’s disease patients, the pre-mortem clinical status was driven by Braak tangle stage. Thal amyloid phase correlated best with 11C-Pittsburgh compound B values, but not Braak tangle stage or cerebral amyloid angiopathy. The 11C-Pittsburgh compound B cut-off point value of 1.4 was approximately equivalent to a Thal amyloid phase of 1–2. PMID:25805643

  14. Center for Interface Science and Catalysis | Theory

    Science.gov Websites

    & Stanford School of Engineering Toggle navigation Home Research Publications People About Academic to overcome challenges associated with the atomic-scale design of catalysts for chemical computational methods we are developing a quantitative description of chemical processes at the solid-gas and

  15. HubbleSite: News

    Science.gov Websites

    HubbleSite Toggle navigation Home News Images Videos Blogs Explore Discoveries Astronomy Technology stars, and yet, star formation is still a vexing question in astronomy. To piece together a more with this form. Inbox Astronomy Subscribe Sign up to receive the latest news, images, and discoveries

  16. Office of Diversity Management and Equal Opportunity

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Office of Diversity Management and Equal Opportunity Search Search ODMEO: Search Search ODMEO: Search Office of Diversity Management and Equal Opportunity Office of Diversity Management and Equal Opportunity Home About ODMEO Leadership Documents News

  17. Office of Water Prediction

    Science.gov Websites

    Toggle navigation National Water Center Home (current) Visualize Map Image Viewer What's New About National Water Center National Water Model National Weather Service National Oceanic and Atmospheric Administration Welcome to the Office of Water Prediction Scientific excellence and innovation driving water

  18. Defense Human Resources Activity > PERSEREC

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Defense Human Resources Activity Search Search Defense Human Resources Activity: Search Search Defense Human Resources Activity: Search Defense Human Resources Activity U.S. Department of Defense Defense Human Resources Activity Overview

  19. Ion Viscosity Mediated by Tangled Magnetic Fields: An Application to Black Hole Accretion Disks

    NASA Technical Reports Server (NTRS)

    Subramanian, Prasad; Becker, Peter A.; Kafatos, Menas

    1996-01-01

    We examine the viscosity associated with the shear stress exerted by ions in the presence of a tangled magnetic field. As an application, we consider the effect of this mechanism on the structure of black hole accretion disks. We do not attempt to include a self-consistent description of the magnetic field. Instead, we assume the existence of a tangled field with coherence length lambda(sub coh), which is the average distance between the magnetic 'kinks' that scatter the particles. For simplicity, we assume that the field is self-similar, and take lambda(sub coh) to be a fixed fraction zeta of the local disk height H. Ion viscosity in the presence of magnetic fields is generally taken to be the cross-field viscosity, wherein the effective mean free path is the ion Larmor radius lambda(sub L), which is much less than the ion-ion Coulomb mean free path A(sub ii) in hot accretion disks. However, we arrive at a formulation for a 'hybrid' viscosity in which the tangled magnetic field acts as an intermediary in the transfer of momentum between different layers in the shear flow. The hybrid viscosity greatly exceeds the standard cross-field viscosity when (lambda/lambda(sub L)) much greater than (lambda(sub L)/lambda(sub ii)), where lambda = ((lambda(sub ii)(sup -1) + lambda(sub (coh)(sup -1))(sup -1) is the effective mean free path for the ions. This inequality is well satisfied in hot accretion disks, which suggests that the ions may play a much larger role in the momentum transfer process in the presence of magnetic fields than was previously thought. The effect of the hybrid viscosity on the structure of a steady-state, two-temperature, quasi-Keplerian accretion disk is analyzed. The hybrid viscosity is influenced by the degree to which the magnetic field is tangled (represented by zeta = lambda(sub coh)), and also by the relative accretion rate M/M(sub E), where M(sub E) = L(sub E)/c(sup 2) and L(sub E) is the Eddington luminosity. We find that ion viscosity in the presence of magnetic fields (hybrid viscosity) can dominate over conventional magnetic viscosity for fields that are tangled on sufficiently small scales.

  20. The Helms-Burton Act: A Strategic Critique.

    DTIC Science & Technology

    1998-03-31

    Sänger, "U.S.- Canadian Split on Cuba Tangles Wal-Mart’s Pajamas ," The New York Times, 6 March 1997, Sec. A, pi. An unintended consequence of the...organizational framework; without strategy, tactics, or historical perspective; without a language, library, data bank , complete intelligence...Sänger, David E. "U.S.-Canadian Split on Cuba Tangles Wal-Mart’s Pajamas ." The New York Times, Sec. A, pi. "Saying Boo to Helms-Burton." The

  1. The influence of phospho-τ on dendritic spines of cortical pyramidal neurons in patients with Alzheimer's disease.

    PubMed

    Merino-Serrais, Paula; Benavides-Piccione, Ruth; Blazquez-Llorca, Lidia; Kastanauskaite, Asta; Rábano, Alberto; Avila, Jesús; DeFelipe, Javier

    2013-06-01

    The dendritic spines on pyramidal cells represent the main postsynaptic elements of cortical excitatory synapses and they are fundamental structures in memory, learning and cognition. In the present study, we used intracellular injections of Lucifer yellow in fixed tissue to analyse over 19 500 dendritic spines that were completely reconstructed in three dimensions along the length of the basal dendrites of pyramidal neurons in the parahippocampal cortex and CA1 of patients with Alzheimer's disease. Following intracellular injection, sections were immunostained for anti-Lucifer yellow and with tau monoclonal antibodies AT8 and PHF-1, which recognize tau phosphorylated at Ser202/Thr205 and at Ser396/404, respectively. We observed that the diffuse accumulation of phospho-tau in a putative pre-tangle state did not induce changes in the dendrites of pyramidal neurons, whereas the presence of tau aggregates forming intraneuronal neurofibrillary tangles was associated with progressive alteration of dendritic spines (loss of dendritic spines and changes in their morphology) and dendrite atrophy, depending on the degree of tangle development. Thus, the presence of phospho-tau in neurons does not necessarily mean that they suffer severe and irreversible effects as thought previously but rather, the characteristic cognitive impairment in Alzheimer's disease is likely to depend on the relative number of neurons that have well developed tangles.

  2. Dynamics of the density of quantized vortex lines in counterflow turbulence: Experimental investigation

    NASA Astrophysics Data System (ADS)

    Varga, E.; Skrbek, L.

    2018-02-01

    Recently the interest in thermal counterflow of superfluid 4He, the most extensively studied form of quantum turbulence, has been renewed. Particularly, an intense theoretical debate has arisen about what form, if any, of the so-called Vinen equation accurately captures the dynamics of vortex line density, L . We address this problem experimentally, in a 21 cm long channel of square 7 ×7 mm2 cross section. Based on large statistics of second-sound data measured in nonequilibrium square-wave modulated thermally induced counterflow we investigate the phase portrait of the general form of the governing dynamical equation and conclude that for sparse tangles (L ≲105cm-2) all proposed forms of this equation based on the concept of a homogeneous random tangle of quantized vortices provide equally adequate descriptions of the growth of L , while for dense tangles (L >105cm-2) none of them is satisfactory or able to account for the significant slow-down in tangle growth rate as the steady state is approached. We claim, however, that agreement with theory is recovered if the geometrical parameter c2 introduced in numerical studies by K. W. Schwarz [Phys. Rev. B 38, 2398 (1988), 10.1103/PhysRevB.38.2398] is allowed to vary with vortex line density which also greatly improves the prediction of the observed early decay rate.

  3. Review: Tau in biofluids - relation to pathology, imaging and clinical features.

    PubMed

    Zetterberg, H

    2017-04-01

    Tau is a microtubule-binding protein that is important for the stability of neuronal axons. It is normally expressed within neurons and is also secreted into the brain interstitial fluid that communicates freely with cerebrospinal fluid (CSF) and, in a more restricted manner, blood via the glymphatic clearance system of the brain. In Alzheimer's disease (AD), neuroaxonal degeneration results in increased release of tau from neurons. Furthermore, tau is truncated and phosphorylated, which leads to aggregation of tau in neurofibrillary tangles of the proximal axoplasm. Neuroaxonal degeneration and tangle formation are reflected by increased concentrations of total tau (T-tau, measured using assays that detect most forms of tau) and phospho-tau (P-tau, measured using assays with antibodies specific to phosphorylated forms of tau). In AD CSF, both T-tau and P-tau concentrations are increased. In stroke and other CNS disorders with neuroaxonal injury but without tangles, T-tau is selectively increased, whereas P-tau concentration often stays normal. In tauopathies (diseases with both neurodegeneration and neurofibrillary tangles) other than AD, CSF T-tau and P-tau concentrations are typically unaltered, which is a puzzling result that warrants further investigation. In the current review, I discuss the association of T-tau and P-tau concentrations in body fluids with neuropathological changes, imaging findings and clinical features in AD and other CNS diseases. © 2017 British Neuropathological Society.

  4. Tau proteins in the cerebrospinal fluid of patients with subacute sclerosing panencephalitis.

    PubMed

    Yuksel, Deniz; Yilmaz, Deniz; Uyar, Neval Y; Senbil, Nesrin; Gurer, Yavuz; Anlar, Banu

    2010-06-01

    Neurodegenerative diseases characterized by cytoskeletal deformation and neurofibrillary tangles are associated with altered levels of tau and related proteins in cerebrospinal fluid (CSF). Neuronal or glial fibrillary tangles have been shown in 20% of subacute sclerosing panencephalitis (SSPE) patients. We therefore investigated CSF samples from 60 newly diagnosed SSPE and 31 neurological control patients for total tau (t-tau), phosphorylated tau (p-tau), and S100-B levels by ELISA. There was no difference between patient and control groups in t-tau and S100-B levels. p-Tau was lower in the SSPE group (p=0.009). Past history of measles infection, measles immunization status, latent period between measles and onset of SSPE, duration of symptoms, frequency of myoclonia, neurological deficit index, stage and progression rate of the disease, CSF glucose levels and cell counts, CSF and serum measles IgG titer, distribution of lesions on brain magnetic resonance imaging were not related to t-tau, p-tau and S100-B levels. Mental status and age were negatively correlated with t-tau, and male gender and EEG abnormalities were associated with higher t-tau levels. The levels of tau proteins in our patients suggest there is no, or only scarce and immature, neurofibrillary tangle formation in SSPE. Autopsy studies showing neurofibrillary tangles might have examined older patients with longer disease and more parenchymal involvement. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  5. Department of Defense Senior Intelligence Oversight Official

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Department of Defense Senior Intelligence Intelligence Oversight Official Department of Defense Senior Intelligence Oversight Official Home About DOD Defense Senior Intelligence Oversight Official Website Michael T. Mahar, DoD SIOO Click here for DoD SIOO

  6. Defense Contract Management Agency

    Science.gov Websites

    , May 24. Click the photo above for more information. Members of the Defense Contract Management Agency for more information. Members of the Defense Contract Management Agency International Region conduct Skip to main content (Press Enter). Toggle navigation Defense Contract Management Agency Search

  7. Alaska Department of Natural Resources

    Science.gov Websites

    Information Information Resource Management Information Resource Management (IRM) maintains the department's DNR's site DNR State of Alaska Toggle main menu visibility Home Contact Us Information Resource Management Recorder's Office/UCC Recorder's Office Recorder's Office Search Uniform Commercial Code (UCC) UCC

  8. III: Trying Something New

    ERIC Educational Resources Information Center

    Rosenfeld, Malke; Rufo, David; Makol, Suzanne; Greco, Ardina; Flores, Chio; Redman, Jeff

    2014-01-01

    The last two sections (EJ1039315 and EJ1039319) presented stories about specific moments or lessons. Also, situations infused with complexity where the writers had to toggle back and forth between providing the larger context and the details that support readers' understanding of that big picture were presented. In this section each story is…

  9. X-ray ptychography, fluorescence microscopy combo sheds new light on trace

    Science.gov Websites

    Research Divisions Computing, Environment and Life Sciences BIOBiosciences CPSComputational Science DSLData CEESCenter for Electrochemical Energy Science CTRCenter for Transportation Research CRIChain Reaction Navigation Toggle Search Energy Environment National Security User Facilities Science Work with Us About

  10. Data from: Solving the Robot-World Hand-Eye(s) Calibration Problem with

    Science.gov Websites

    Iterative Methods | National Agricultural Library Skip to main content Home National Agricultural Library United States Department of Agriculture Ag Data Commons Beta Toggle navigation Datasets . License U.S. Public Domain Funding Source(s) National Science Foundation IOS-1339211 Agricultural Research

  11. Clean Cities Technical Assistance | State, Local, and Tribal Governments |

    Science.gov Websites

    NREL Toggle navigation Menu Technical Assistance Technical Assistance States Tribes Clean » State, Local, and Tribal Governments » Clean Cities Technical Assistance Clean Cities Technical reduce petroleum use in transportation by providing technical assistance, educational and outreach

  12. Non-Back-Drivable, Freewheeling Coupling

    NASA Technical Reports Server (NTRS)

    Llewellin, W.

    1986-01-01

    Cables reeled in and out with less risk of tangling. Opposing teeth engage with clockwise rotation and disengage with clockwise rotation of crank. Driving plate moves axially with respect to driven plate on ball points to engage and disengage. Clutch developed for reeling and unreeling tether line used to link astronaut to space vehicle. Allows line pulled out freely and helps to prevent line from tangling in reel housing when crank is turned backward. New clutch concept also applicable to fishing reels, toys, and safety-line mechanisms.

  13. Decision making on fitness landscapes

    NASA Astrophysics Data System (ADS)

    Arthur, R.; Sibani, P.

    2017-04-01

    We discuss fitness landscapes and how they can be modified to account for co-evolution. We are interested in using the landscape as a way to model rational decision making in a toy economic system. We develop a model very similar to the Tangled Nature Model of Christensen et al. that we call the Tangled Decision Model. This is a natural setting for our discussion of co-evolutionary fitness landscapes. We use a Monte Carlo step to simulate decision making and investigate two different decision making procedures.

  14. Motor cortex embeds muscle-like commands in an untangled population response

    PubMed Central

    Russo, Abigail A.; Bittner, Sean R.; Perkins, Sean M.; Seely, Jeffrey S.; London, Brian M.; Lara, Antonio H.; Miri, Andrew; Marshall, Najja J.; Kohn, Adam; Jessell, Thomas M.; Abbott, Laurence F.; Cunningham, John P.; Churchland, Mark M.

    2018-01-01

    Summary Primate motor cortex projects to spinal interneurons and motor neurons, suggesting that motor cortex activity may be dominated by muscle-like commands. Extensive observations during reaching lend support to this view, but evidence remains ambiguous and much-debated. To provide a different perspective, we employed a novel behavioral paradigm that affords extensive comparison between time-evolving neural and muscle activity. We found that single motor cortex neurons displayed many muscle-like properties, but the structure of population activity was not muscle-like. Unlike muscle activity, neural activity was structured to avoid ‘tangling’: moments where similar activity patterns led to dissimilar future patterns. Avoidance of tangling was present across tasks and species. Network models revealed a potential reason for this consistent feature: low tangling confers noise robustness. Finally, we were able to predict motor cortex activity from muscle activity alone, by leveraging the hypothesis that muscle-like commands are embedded in additional structure that yields low tangling. PMID:29398358

  15. Memory complaints are related to Alzheimer disease pathology in older persons.

    PubMed

    Barnes, L L; Schneider, J A; Boyle, P A; Bienias, J L; Bennett, D A

    2006-11-14

    To study the relationship between Alzheimer disease (AD) pathology and memory complaints proximate to death. A group of 90 older persons underwent detailed clinical evaluations and brain autopsy at death. The evaluations included administration of questions on subjective memory complaints and clinical classification of dementia and AD. On postmortem examination, neuritic plaques, diffuse plaques, and neurofibrillary tangles in tissue samples from five cortical regions were counted, and a summary measure of overall AD pathology was derived. In addition, amyloid load and tau tangles were quantified in eight regions. In multiple linear regression models adjusted for age, sex, and education, memory complaints were associated with AD pathology, including both amyloid and tau tangles. Subsequent analyses demonstrated that the relationship between memory complaints and AD pathology was present in those with and without dementia, and could not be explained by the potentially confounding effects of depressive symptoms or coexisting common chronic health problems. Memory complaints in older persons may indicate self awareness of a degenerative process.

  16. A Note on the Propagation of Quantized Vortex Rings Through a Quantum Turbulence Tangle: Energy Transport or Energy Dissipation?

    NASA Astrophysics Data System (ADS)

    Laurie, Jason; Baggaley, Andrew W.

    2015-07-01

    We investigate quantum vortex ring dynamics at scales smaller than the inter-vortex spacing in quantum turbulence. Through geometrical arguments and high-resolution numerical simulations, we examine the validity of simple estimates for the mean free path and the structure of vortex rings post-reconnection. We find that a large proportion of vortex rings remain coherent objects where approximately of their energy is preserved. This leads us to consider the effectiveness of energy transport in turbulent tangles. Moreover, we show that in low density tangles, appropriate for the ultra-quantum regime, ring emission cannot be ruled out as an important mechanism for energy dissipation. However at higher vortex line densities, typically associated with the quasi-classical regime, loop emission is expected to make a negligible contribution to energy dissipation, even allowing for the fact that our work shows rings can survive multiple reconnection events. Hence the Kelvin wave cascade seems the most plausible mechanism leading to energy dissipation.

  17. Magnetospheric Multiscale Satellites Observations of Parallel Electric Fields Associated with Magnetic Reconnection

    NASA Technical Reports Server (NTRS)

    Ergun, R. E.; Goodrich, K. A.; Wilder, F. D.; Holmes, J. C.; Stawarz, J. E.; Eriksson, S.; Sturner, A. P.; Malaspina, D. M.; Usanova, M. E.; Torbert, R. B.; hide

    2016-01-01

    We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E (sub parallel)) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E (sub parallel) events near the electron diffusion region have amplitudes on the order of 100 millivolts per meter, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E (sub parallel) events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E (sub parallel) events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.

  18. Tangle-Free Finite Element Mesh Motion for Ablation Problems

    NASA Technical Reports Server (NTRS)

    Droba, Justin

    2016-01-01

    Mesh motion is the process by which a computational domain is updated in time to reflect physical changes in the material the domain represents. Such a technique is needed in the study of the thermal response of ablative materials, which erode when strong heating is applied to the boundary. Traditionally, the thermal solver is coupled with a linear elastic or biharmonic system whose sole purpose is to update mesh node locations in response to altering boundary heating. Simple mesh motion algorithms rely on boundary surface normals. In such schemes, evolution in time will eventually cause the mesh to intersect and "tangle" with itself, causing failure. Furthermore, such schemes are greatly limited in the problems geometries on which they will be successful. This paper presents a comprehensive and sophisticated scheme that tailors the directions of motion based on context. By choosing directions for each node smartly, the inevitable tangle can be completely avoided and mesh motion on complex geometries can be modeled accurately.

  19. Cdk5: one of the links between senile plaques and neurofibrillary tangles?

    PubMed

    Lee, Ming-Sum; Tsai, Li-Huei

    2003-04-01

    The relationship between amyloid plaques and neurofibrillary tangles, the two pathologic hallmarks of Alzheimer's disease (AD), is an unknown and controversial subject. However, emerging evidence from genetic and biochemical studies suggests that accumulation of amyloid beta peptides may play a causative role in AD pathogenesis. This led to the amyloid hypothesis, which proposes that amyloid beta peptides disrupt neuronal metabolic and ionic homeostasis and cause aberrant activation of kinases and/or inhibition of phosphatases. The resulting alteration in kinase and phosphatase activities ultimately leads to hyperphosphorylation of tau and formation of neurofibrillary tangles. Cyclin-dependent kinase 5 (Cdk5) is a tau kinase whose activity is induced by amyloid beta peptides. Its deregulation may represent one of the signal transduction pathways that connect amyloid beta toxicity to tau hyperphosphorylation. This article reviews the functions and regulation of Cdk5. Evidence that suggests deregulation of Cdk5 activity in AD by virtue of calpain cleavage of its activator p35 to p25 will be discussed.

  20. Magnetospheric Multiscale Satellites Observations of Parallel Electric Fields Associated with Magnetic Reconnection.

    PubMed

    Ergun, R E; Goodrich, K A; Wilder, F D; Holmes, J C; Stawarz, J E; Eriksson, S; Sturner, A P; Malaspina, D M; Usanova, M E; Torbert, R B; Lindqvist, P-A; Khotyaintsev, Y; Burch, J L; Strangeway, R J; Russell, C T; Pollock, C J; Giles, B L; Hesse, M; Chen, L J; Lapenta, G; Goldman, M V; Newman, D L; Schwartz, S J; Eastwood, J P; Phan, T D; Mozer, F S; Drake, J; Shay, M A; Cassak, P A; Nakamura, R; Marklund, G

    2016-06-10

    We report observations from the Magnetospheric Multiscale satellites of parallel electric fields (E_{∥}) associated with magnetic reconnection in the subsolar region of the Earth's magnetopause. E_{∥} events near the electron diffusion region have amplitudes on the order of 100  mV/m, which are significantly larger than those predicted for an antiparallel reconnection electric field. This Letter addresses specific types of E_{∥} events, which appear as large-amplitude, near unipolar spikes that are associated with tangled, reconnected magnetic fields. These E_{∥} events are primarily in or near a current layer near the separatrix and are interpreted to be double layers that may be responsible for secondary reconnection in tangled magnetic fields or flux ropes. These results are telling of the three-dimensional nature of magnetopause reconnection and indicate that magnetopause reconnection may be often patchy and/or drive turbulence along the separatrix that results in flux ropes and/or tangled magnetic fields.

  1. Persistent tangled vortex rings in generic excitable media.

    PubMed

    Winfree, A T

    1994-09-15

    Excitable media are exemplified by a range of living systems, such as mammalian heart muscle and its cells and Xenopus eggs. They also occur in non-living systems such as the autocatalytic Belousov-Zhabotinsky reaction. In most of these systems, activity patterns, such as concentration waves, typically radiate as spiral waves from a vortex of excitation created by some nonuniform stimulus. In three-dimensional systems, the vortex is commonly a line, and these vortex lines can form linked and knotted rings which contract into compact, particle-like bundles. In most previous work these stable 'organizing centres' have been found to be symmetrical and can be classified topologically. Here I show through numerical studies of a generic excitable medium that the more general configuration of vortex lines is a turbulent tangle, which is robust against changes in the parameters of the system or perturbations to it. In view of their stability, I suggest that these turbulent tangles should be observable in any of the many known excitable media.

  2. Rapunzel Loves Merida: Melodramatic Expressions of Lesbian Girlhood and Teen Romance in Tangled, Brave, and Femslash.

    PubMed

    Kapurch, Katie

    2015-01-01

    This article explores the melodramatic expression of lesbian girlhood and teen romance in Disney's Tangled (2010) and Disney Pixar's Brave (2012), as well as "Meripunzel" femslash, fan-authored romantic pairings of the animations' female protagonists. First, Anne Sexton's poem, "Rapunzel," offers a literary precedent for exploring lesbian themes in the fairy tale. The next section shows how Tangled and Brave invoke the narrative conventions of the family melodrama. This generic association reveals the films' uses of rhetoric familiar to youth coming-out narratives, as well as other visual and aural coding suggestive of queer styles. The last section shows how Meripunzel femslash taps into the films' existing melodramatic narrative forms and visual aesthetics, rehearsing their coming-out rhetoric while addressing the pleasures of and problems facing lesbian teen romance. I conclude by problematizing the often conventional expressions of lesbian girlhood in femslash, ultimately arguing for their empowering potential, especially as they indicate revised definitions of "princess."

  3. Dipeptidyl Peptidase 10 (DPP10789): A Voltage Gated Potassium Channel Associated Protein Is Abnormally Expressed in Alzheimer's and Other Neurodegenerative Diseases

    PubMed Central

    Gai, Wei-Ping; Abbott, Catherine A.

    2014-01-01

    The neuropathological features associated with Alzheimer's disease (AD) include the presence of extracellular amyloid-β peptide-containing plaques and intracellular tau positive neurofibrillary tangles and the loss of synapses and neurons in defined regions of the brain. Dipeptidyl peptidase 10 (DPP10) is a protein that facilitates Kv4 channel surface expression and neuronal excitability. This study aims to explore DPP10789 protein distribution in human brains and its contribution to the neurofibrillary pathology of AD and other tauopathies. Immunohistochemical analysis revealed predominant neuronal staining of DPP10789 in control brains, and the CA1 region of the hippocampus contained strong reactivity in the distal dendrites of the pyramidal cells. In AD brains, robust DPP10789 reactivity was detected in neurofibrillary tangles and plaque-associated dystrophic neurites, most of which colocalized with the doubly phosphorylated Ser-202/Thr-205 tau epitope. DPP10789 positive neurofibrillary tangles and plaque-associated dystrophic neurites also appeared in other neurodegenerative diseases such as frontotemporal lobar degeneration, diffuse Lewy body disease, and progressive supranuclear palsy. Occasional DPP10789 positive neurofibrillary tangles and neurites were seen in some aged control brains. Western blot analysis showed both full length and truncated DPP10789 fragments with the later increasing significantly in AD brains compared to control brains. Our results suggest that DPP10789 is involved in the pathology of AD and other neurodegenerative diseases. PMID:25025038

  4. Tangled nonlinear driven chain reactions of all optical singularities

    NASA Astrophysics Data System (ADS)

    Vasil'ev, V. I.; Soskin, M. S.

    2012-03-01

    Dynamics of polarization optical singularities chain reactions in generic elliptically polarized speckle fields created in photorefractive crystal LiNbO3 was investigated in details Induced speckle field develops in the tens of minutes scale due to photorefractive 'optical damage effect' induced by incident beam of He-Ne laser. It was shown that polarization singularities develop through topological chain reactions of developing speckle fields driven by photorefractive nonlinearities induced by incident laser beam. All optical singularities (C points, optical vortices, optical diabolos,) are defined by instantaneous topological structure of the output wavefront and are tangled by singular optics lows. Therefore, they have develop in tangled way by six topological chain reactions driven by nonlinear processes in used nonlinear medium (photorefractive LiNbO3:Fe in our case): C-points and optical diabolos for right (left) polarized components domains with orthogonally left (right) polarized optical vortices underlying them. All elements of chain reactions consist from loop and chain links when nucleated singularities annihilated directly or with alien singularities in 1:9 ratio. The topological reason of statistics was established by low probability of far enough separation of born singularities pair from existing neighbor singularities during loop trajectories. Topology of developing speckle field was measured and analyzed by dynamic stokes polarimetry with few seconds' resolution. The hierarchy of singularities govern scenario of tangled chain reactions was defined. The useful space-time data about peculiarities of optical damage evolution were obtained from existence and parameters of 'islands of stability' in developing speckle fields.

  5. Catalytic ionic hydrogenation of ketones using tungsten or molybdenum organometallic species

    DOEpatents

    Voges, Mark; Bullock, R. Morris

    2000-01-01

    The present invention is a process for the catalytic hydrogenation of ketones and aldehydes to alcohols at low temperatures and pressures using organometallic molybdenum and tungsten complexes. The functional group is selected from groups represented by the formulas R(C.dbd.O)R' and R(C.dbd.O)H, wherein R and R' are selected from hydrogen or any alkyl or aryl group. The active catalyst for the process has the form: [CpM(CO).sub.2 (PR*.sub.3) L].sup.+ A.sup.-, where Cp=.eta..sup.5 -R.sup..tangle-solidup..sub.m C.sub.5 H.sub.5-m and R.sup..tangle-solidup. represents an alkyl group or a halogen (F, Cl, Br, I) or R.sup..tangle-solidup. =OR' (where R'=H, an alkyl group or an aryl group) or R.sup..tangle-solidup. =CO.sub.2 R' (where R'=H, an alkyl group or an aryl group) and m=0 to 5; M represents a molybdenum atom or a tungsten atom; R*.sub.3 represents three hydrocarbon groups selected from a cyclohexyl group (C.sub.6 H.sub.11), a methyl group (CH.sub.3), and a phenyl group (C.sub.6 H.sub.5) and all three R* groups can be the same or different or two of the three groups can be the same; L represents a ligand; and A.sup.- represents an anion. In another embodiment, one, two or three of the R* groups can be an OR*.

  6. Non-Lethal Weapons Program

    Science.gov Websites

    ), 26th Marine Expeditionary Unit (MEU), practice non-lethal control techniques during a non-lethal Skip to main content (Press Enter). Toggle navigation Non-Lethal Weapons Program Search Search JNLWP: Search Search JNLWP: Search Non-Lethal Weapons Program U.S. Department of Defense Non-Lethal

  7. Modulation of starch digestion for slow glucose release through "toggling" of activities of mucosal "alpha"-glucosidases

    USDA-ARS?s Scientific Manuscript database

    Starch digestion involves the breakdown by alpha-amylase to small linear and branched malto-oligosaccharides, which are in turn hydrolyzed to glucose by the mucosal alpha-glucosidases, maltase-glucoamylase (MGAM) and sucrase-isomaltase (SI). MGAM and SI are anchored to the small intestinal brush-bor...

  8. 40 CFR 63.5460 - What definitions apply to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... use include: toggling, hanging, pasting, and vacuum drying. Finish add-on means the amount of solid material deposited on the leather substrate due to finishing operations. Typically, the solid deposition is a dye or other chemical used to enhance the color and performance of the leather. Finish add-on is...

  9. 40 CFR 63.5460 - What definitions apply to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... use include: toggling, hanging, pasting, and vacuum drying. Finish add-on means the amount of solid material deposited on the leather substrate due to finishing operations. Typically, the solid deposition is a dye or other chemical used to enhance the color and performance of the leather. Finish add-on is...

  10. U.S. Northern Command > Newsroom > Press Releases

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation U.S. Northern Command Search Search USNORTHCOM: Search Search USNORTHCOM: Search U.S. Northern Command U.S. Northern Command Home Leadership , 2018 NORAD and USNORTHCOM to host change of command ceremony Nov. 30, 2017 United States, Mexico to

  11. Crashworthy Troop Seat Testing Program

    DTIC Science & Technology

    1977-11-01

    19 ’rest 4 . . . . . . . . . .. . 29 | Detail Design’Finalization. .... 29 Vertical Wire - Bending Energy Attenuator 32 Toggle Latch...Strut Wire - Bending Attenuator Force Deflection. . . . ................... 28 15 Notched Wire and Pin Anchorage Test Specimen . 30 16 Quick-Disconnect...and Hold-Down Cable ......... 31 17 Failed Hold-Down Cable ...... . . . . 31 18 Wire - Bending Tension/Compression Energy Attenuator

  12. Chief Information Officer > DoDSection508

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  13. Biographies of Senior Defense Officials

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  14. Chief Information Officer > Library

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  15. Chief Information Officer > In the News

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  16. Chief Information Officer > About DoD CIO

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  17. Ferguson Troubleshoots GPC 3

    NASA Image and Video Library

    2011-07-11

    S135-E-007350 (11 July 2011) --- NASA astronaut Chris Ferguson, STS-135 mission commander, toggles switches on the overhead panel of the forward flight deck of the space shuttle Atlantis. The image was recorded during the mission's fourth day of activities in Earth orbit and second day while being docked with the International Space Station. Photo credit: NASA

  18. outreach | News

    Science.gov Websites

    . Photo: Elliott McCrory On March 3, 71 local high school students graduated from the winter session of Figures STEM program for local students February 20, 2018 | Sarah Lawhun After watching short videos on Students and teachers Media News Navbar Toggle Newsroom News and features Press releases Fermilab in the

  19. Gulf Dolphins Slideshow | NOAA Gulf Spill Restoration

    Science.gov Websites

    Skip to main content Home Home Toggle navigation Search form Search Search the web Search NOAA Gulf Spill Restoration Search Home About Us Trustees Contact Us How We Restore Planning Damage Assessment Archive Home Gulf Dolphins Slideshow Gulf Dolphins Slideshow share Posted on March 23, 2012 | Assessment

  20. Christmas Light Display

    NASA Astrophysics Data System (ADS)

    Ross, Arthur; Renfro, Timothy

    2012-03-01

    The Digital Electronics class at McMurry University created a Christmas light display that toggles the power of different strands of lights, according to what frequencies are played in a song, as an example of an analog to digital circuit. This was accomplished using a BA3830S IC six-band audio filter and six solid-state relays.

  1. Fermilab | Science | Questions for the Universe | Einstein's Dream of

    Science.gov Websites

    Navbar Toggle Search Search Home About Science Jobs Contact Phone Book Newsroom Newsroom News and Tevatron experiments Tevatron operation Shutdown process For the media Video of shutdown event Guest book Home Contact Phone Book Fermilab at Work For Industry Jobs Interact Facebook Twitter Instagram Google

  2. The Better World Project - Home

    Science.gov Websites

    Toggle navigation Featured Stories Past Reports FAQ Background Information 500 Better World Stories ... and Counting! Thanks to the hard work of AUTM members around the world, the Better World Project Better World Project Database. Simply type in the criteria you're looking for. Add Your Story to the

  3. The Relationship between Software Design and Children's Engagement

    ERIC Educational Resources Information Center

    Buckleitner, Warren

    2006-01-01

    This study was an attempt to measure the effects of praise and reinforcement on children in a computer learning setting. A sorting game was designed to simulate 2 interaction styles. One style, called high computer control, provided frequent praise and coaching. The other, called high child control, had narration and praise toggled off. A…

  4. ::: American Indians of the Pacific Northwest Collection :::

    Science.gov Websites

    Ask Us! University of Washington Libraries Digital Collections Toggle navigation Browse Special learn from the images and writings of the time...This site provides an extensive digital collection of digital databases includes over 2,300 original photographs as well as over 1,500 pages from the Annual

  5. Aversive Learning and Appetitive Motivation Toggle Feed-Forward Inhibition in the Drosophila Mushroom Body.

    PubMed

    Perisse, Emmanuel; Owald, David; Barnstedt, Oliver; Talbot, Clifford B; Huetteroth, Wolf; Waddell, Scott

    2016-06-01

    In Drosophila, negatively reinforcing dopaminergic neurons also provide the inhibitory control of satiety over appetitive memory expression. Here we show that aversive learning causes a persistent depression of the conditioned odor drive to two downstream feed-forward inhibitory GABAergic interneurons of the mushroom body, called MVP2, or mushroom body output neuron (MBON)-γ1pedc>α/β. However, MVP2 neuron output is only essential for expression of short-term aversive memory. Stimulating MVP2 neurons preferentially inhibits the odor-evoked activity of avoidance-directing MBONs and odor-driven avoidance behavior, whereas their inhibition enhances odor avoidance. In contrast, odor-evoked activity of MVP2 neurons is elevated in hungry flies, and their feed-forward inhibition is required for expression of appetitive memory at all times. Moreover, imposing MVP2 activity promotes inappropriate appetitive memory expression in food-satiated flies. Aversive learning and appetitive motivation therefore toggle alternate modes of a common feed-forward inhibitory MVP2 pathway to promote conditioned odor avoidance or approach. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. Analysis and design of a genetic circuit for dynamic metabolic engineering.

    PubMed

    Anesiadis, Nikolaos; Kobayashi, Hideki; Cluett, William R; Mahadevan, Radhakrishnan

    2013-08-16

    Recent advances in synthetic biology have equipped us with new tools for bioprocess optimization at the genetic level. Previously, we have presented an integrated in silico design for the dynamic control of gene expression based on a density-sensing unit and a genetic toggle switch. In the present paper, analysis of a serine-producing Escherichia coli mutant shows that an instantaneous ON-OFF switch leads to a maximum theoretical productivity improvement of 29.6% compared to the mutant. To further the design, global sensitivity analysis is applied here to a mathematical model of serine production in E. coli coupled with a genetic circuit. The model of the quorum sensing and the toggle switch involves 13 parameters of which 3 are identified as having a significant effect on serine concentration. Simulations conducted in this reduced parameter space further identified the optimal ranges for these 3 key parameters to achieve productivity values close to the maximum theoretical values. This analysis can now be used to guide the experimental implementation of a dynamic metabolic engineering strategy and reduce the time required to design the genetic circuit components.

  7. Off and back-on again: a tumor suppressor's tale.

    PubMed

    Acosta, Jonuelle; Wang, Walter; Feldser, David M

    2018-06-01

    Tumor suppressor genes play critical roles orchestrating anti-cancer programs that are both context dependent and mechanistically diverse. Beyond canonical tumor suppressive programs that control cell division, cell death, and genome stability, unexpected tumor suppressor gene activities that regulate metabolism, immune surveillance, the epigenetic landscape, and others have recently emerged. This diversity underscores the important roles these genes play in maintaining cellular homeostasis to suppress cancer initiation and progression, but also highlights a tremendous challenge in discerning precise context-specific programs of tumor suppression controlled by a given tumor suppressor. Fortunately, the rapid sophistication of genetically engineered mouse models of cancer has begun to shed light on these context-dependent tumor suppressor activities. By using techniques that not only toggle "off" tumor suppressor genes in nascent tumors, but also facilitate the timely restoration of gene function "back-on again" in disease specific contexts, precise mechanisms of tumor suppression can be revealed in an unbiased manner. This review discusses the development and implementation of genetic systems designed to toggle tumor suppressor genes off and back-on again and their potential to uncover the tumor suppressor's tale.

  8. Programmable cells: Interfacing natural and engineered gene networks

    NASA Astrophysics Data System (ADS)

    Kobayashi, Hideki; Kærn, Mads; Araki, Michihiro; Chung, Kristy; Gardner, Timothy S.; Cantor, Charles R.; Collins, James J.

    2004-06-01

    Novel cellular behaviors and characteristics can be obtained by coupling engineered gene networks to the cell's natural regulatory circuitry through appropriately designed input and output interfaces. Here, we demonstrate how an engineered genetic circuit can be used to construct cells that respond to biological signals in a predetermined and programmable fashion. We employ a modular design strategy to create Escherichia coli strains where a genetic toggle switch is interfaced with: (i) the SOS signaling pathway responding to DNA damage, and (ii) a transgenic quorum sensing signaling pathway from Vibrio fischeri. The genetic toggle switch endows these strains with binary response dynamics and an epigenetic inheritance that supports a persistent phenotypic alteration in response to transient signals. These features are exploited to engineer cells that form biofilms in response to DNA-damaging agents and cells that activate protein synthesis when the cell population reaches a critical density. Our work represents a step toward the development of "plug-and-play" genetic circuitry that can be used to create cells with programmable behaviors. heterologous gene expression | synthetic biology | Escherichia coli

  9. Action of Molecular Switches in GPCRs - Theoretical and Experimental Studies

    PubMed Central

    Trzaskowski, B; Latek, D; Yuan, S; Ghoshdastider, U; Debinski, A; Filipek, S

    2012-01-01

    G protein coupled receptors (GPCRs), also called 7TM receptors, form a huge superfamily of membrane proteins that, upon activation by extracellular agonists, pass the signal to the cell interior. Ligands can bind either to extracellular N-terminus and loops (e.g. glutamate receptors) or to the binding site within transmembrane helices (Rhodopsin-like family). They are all activated by agonists although a spontaneous auto-activation of an empty receptor can also be observed. Biochemical and crystallographic methods together with molecular dynamics simulations and other theoretical techniques provided models of the receptor activation based on the action of so-called “molecular switches” buried in the receptor structure. They are changed by agonists but also by inverse agonists evoking an ensemble of activation states leading toward different activation pathways. Switches discovered so far include the ionic lock switch, the 3-7 lock switch, the tyrosine toggle switch linked with the nPxxy motif in TM7, and the transmission switch. The latter one was proposed instead of the tryptophan rotamer toggle switch because no change of the rotamer was observed in structures of activated receptors. The global toggle switch suggested earlier consisting of a vertical rigid motion of TM6, seems also to be implausible based on the recent crystal structures of GPCRs with agonists. Theoretical and experimental methods (crystallography, NMR, specific spectroscopic methods like FRET/BRET but also single-molecule-force-spectroscopy) are currently used to study the effect of ligands on the receptor structure, location of stable structural segments/domains of GPCRs, and to answer the still open question on how ligands are binding: either via ensemble of conformational receptor states or rather via induced fit mechanisms. On the other hand the structural investigations of homo- and heterodimers and higher oligomers revealed the mechanism of allosteric signal transmission and receptor activation that could lead to design highly effective and selective allosteric or ago-allosteric drugs. PMID:22300046

  10. Action of molecular switches in GPCRs--theoretical and experimental studies.

    PubMed

    Trzaskowski, B; Latek, D; Yuan, S; Ghoshdastider, U; Debinski, A; Filipek, S

    2012-01-01

    G protein coupled receptors (GPCRs), also called 7TM receptors, form a huge superfamily of membrane proteins that, upon activation by extracellular agonists, pass the signal to the cell interior. Ligands can bind either to extracellular N-terminus and loops (e.g. glutamate receptors) or to the binding site within transmembrane helices (Rhodopsin-like family). They are all activated by agonists although a spontaneous auto-activation of an empty receptor can also be observed. Biochemical and crystallographic methods together with molecular dynamics simulations and other theoretical techniques provided models of the receptor activation based on the action of so-called "molecular switches" buried in the receptor structure. They are changed by agonists but also by inverse agonists evoking an ensemble of activation states leading toward different activation pathways. Switches discovered so far include the ionic lock switch, the 3-7 lock switch, the tyrosine toggle switch linked with the nPxxy motif in TM7, and the transmission switch. The latter one was proposed instead of the tryptophan rotamer toggle switch because no change of the rotamer was observed in structures of activated receptors. The global toggle switch suggested earlier consisting of a vertical rigid motion of TM6, seems also to be implausible based on the recent crystal structures of GPCRs with agonists. Theoretical and experimental methods (crystallography, NMR, specific spectroscopic methods like FRET/BRET but also single-molecule-force-spectroscopy) are currently used to study the effect of ligands on the receptor structure, location of stable structural segments/domains of GPCRs, and to answer the still open question on how ligands are binding: either via ensemble of conformational receptor states or rather via induced fit mechanisms. On the other hand the structural investigations of homoand heterodimers and higher oligomers revealed the mechanism of allosteric signal transmission and receptor activation that could lead to design highly effective and selective allosteric or ago-allosteric drugs.

  11. Toggling of seismicity by the 1997 Kagoshima earthquake couplet: A demonstration of time-dependent stress transfer

    USGS Publications Warehouse

    Toda, S.; Stein, R.

    2003-01-01

    Two M ??? 6 well-recorded strike-slip earthquakes struck just 4 km and 48 days apart in Kagoshima prefecture, Japan, in 1997, providing an opportunity to study earthquake interaction. Aftershocks are abundant where the Coulomb stress is calculated to have been increased by the first event, and they abruptly stop where the stress is dropped by the second event. This ability of the main shocks to toggle seismicity on and off argues that static stress changes play a major role in exciting aftershocks, whereas the dynamic Coulomb stresses, which should only promote seismicity, appear to play a secondary role. If true, the net stress changes from a sequence of earthquakes might be expected to govern the subsequent seismicity distribution. However, adding the stress changes from the two Kagoshima events does not fully capture the ensuing seismicity, such as its rate change, temporal decay, or migration away from the ends of the ruptures. We therefore implement a stress transfer model that incorporates rate/state friction, in which seismicity is treated as a sequence of independent nucleation events that are dependent on the fault slip, slip rate, and elapsed time since the last event. The model reproduces the temporal response of seismicity to successive stress changes, including toggling, decay, and aftershock migration. Nevertheless, the match of observed to predicted seismicity is quite imperfect, due perhaps to inadequate knowledge of several model parameters. However, to demonstrate the potential of this approach, we build a probabilistic forecast of larger earthquakes on the expected rate of small aftershocks, taking advantage of the large statistical sample the small shocks afford. Not surprisingly, such probabilities are highly time- and location-dependent: During the first decade after the main shocks, the seismicity rate and the chance of successive large shocks are about an order of magnitude higher than the background rate and are concentrated exclusively in the stress triggering zones. Copyright 2003 by the American Geophysical Uion.

  12. Ultralow contact angle hysteresis and no-aging effects in superhydrophobic tangled nanofiber structures generated by controlling the pore size of a 99.5% aluminum foil

    NASA Astrophysics Data System (ADS)

    Lee, Sangmin; Hwang, Woonbong

    2009-03-01

    Superhydrophobic surfaces designed to improve hydrophobicity have high advancing contact angles corresponding to the Cassie state, but these surfaces also exhibit high contact angle hysteresis. We report here a simple and inexpensive method for fabricating superhydrophobic tangled nanofiber structures with ultralow contact angle hysteresis and no-aging degradation, based on a widening process. The resulting nanostructures are suitable for diverse applications including microfluidic devices for biological studies and industrial self-cleaning products for automobiles, ships and houses.

  13. Upper bound on three-tangles of reduced states of four-qubit pure states

    NASA Astrophysics Data System (ADS)

    Sharma, S. Shelly; Sharma, N. K.

    2017-06-01

    Closed formulas for upper bounds on three-tangles of three-qubit reduced states in terms of three-qubit-invariant polynomials of pure four-qubit states are obtained. Our results offer tighter constraints on total three-way entanglement of a given qubit with the rest of the system than those used by Regula et al. [Phys. Rev. Lett. 113, 110501 (2014), 10.1103/PhysRevLett.113.110501 and Phys. Rev. Lett. 116, 049902(E) (2016)], 10.1103/PhysRevLett.116.049902 to verify monogamy of four-qubit quantum entanglement.

  14. Chief Information Officer > About DoD CIO > Organization > DCIO R&A

    Science.gov Websites

    provide strategy, leadership, and guidance to create a unified information management and technology Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department

  15. 49 CFR Appendix A to Part 180 - Internal Self-closing Stop Valve Emergency Closure Test for Liquefied Compressed Gases

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Test for Liquefied Compressed Gases A Appendix A to Part 180 Transportation Other Regulations Relating... Compressed Gases 1. In performing this test, all internal self-closing stop valves must be opened. Each.... 2. On pump-actuated pressure differential internal valves, the three-way toggle valve handle or its...

  16. Information Technology Exchange Program (ITEP) - U.S. Department of Defense

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  17. Web and Internet-based Capabilities (IbC) Policies - U.S. Department of

    Science.gov Websites

    Defense Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4

  18. Chief Information Officer > About DoD CIO > Organization > DCIO IE

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  19. Learn More at Public Meetings | NOAA Gulf Spill Restoration

    Science.gov Websites

    Skip to main content Home Home Toggle navigation Search form Search Search the web Search NOAA Gulf Spill Restoration Search Home About Us Trustees Contact Us How We Restore Planning Damage Assessment Archive Home Learn More at Public Meetings Learn More at Public Meetings Get Involved in Restoring the

  20. Study of Man-Machine Communications Systems for Disabled Persons (The Handicapped). Volume VII. Final Report.

    ERIC Educational Resources Information Center

    Kafafian, Haig

    Teaching instructions, lesson plans, and exercises are provided for severely physically and/or neurologically handicapped persons learning to use the Cybertype electric writing machine with a tongue-body keyboard. The keyboard, which has eight double-throw toggle switches and a three-position state-selector switch, is designed to be used by…

  1. Fermilab | Science | Questions for the Universe | Einstein's Dream of

    Science.gov Websites

    Toggle Search Search Home About Science Jobs Contact Phone Book Newsroom Newsroom News and features Press process For the media Video of shutdown event Guest book Tevatron Impact June 11, 2012 About the symposium Office of Science Security, Privacy, Legal Use of Cookies Quick Links Home Contact Phone Book Fermilab at

  2. About | DOE Data Explorer

    Science.gov Websites

    skip to main content DDE Toggle Navigation Home About DDE FAQs DOE Data ID Service Data ID Service Data ID Service Workshops Contact Us dataexplorer Search For Terms: + Advanced Search × Advanced /Simulations Figures/Plots Genome/Genetics Data Interactive Data Map(s) Multimedia Numeric Data Specialized Mix

  3. “End-Stage” Neurofibrillary Tangle Pathology in Preclinical Alzheimer's Disease: Fact or Fiction?

    PubMed Central

    Abner, Erin L.; Kryscio, Richard J.; Schmitt, Frederick A.; SantaCruz, Karen S.; Jicha, Gregory A.; Lin, Yushun; Neltner, Janna M.; Smith, Charles D.; Van Eldik, Linda J.; Nelson, Peter T.

    2011-01-01

    Among individuals who were cognitively intact before death, autopsies may reveal some Alzheimer's disease-type pathology. The presence of end-stage pathology in cognitively intact persons would support the hypothesis that pathological markers are epiphenomena. We assessed advanced neurofibrillary (Braak stages V and VI) pathology focusing on nondemented individuals. Data from the National Alzheimer's Coordinating Center database (n = 4,690 included initially) and from the Nun Study (n = 526 included initially) were analyzed, with antemortem information about global cognition and careful postmortem studies available from each case. Global cognition (final Mini-Mental State Examination scores [MMSE] and clinical ‘dementia’ status) was correlated with neuropathology, including the severity of neurofibrillary pathology (Braak stages and neurofibrillary tangle counts in cerebral neocortex). Analyses support three major findings: 1. Braak stage V cases and Braak VI cases are significantly different from each other in terms of associated antemortem cognition; 2. There is an appreciable range of pathology within the category of Braak stage VI based on tangle counts such that brains with the most neurofibrillary tangles in neocortex always had profound antemortem cognitive impairment; and 3. There was no nondemented case with final MMSE score of 30 within a year of life and Braak stage VI pathology. It may be inappropriate to combine Braak stages V and VI cases, particularly in patients with early cognitive dysfunction, since the two pathological stages appear to differ dramatically in terms of both pathological severity and antemortem cognitive status. There is no documented example of truly end-stage neurofibrillary pathology coexisting with intact cognition. PMID:21471646

  4. Universal statistics of vortex tangles in three-dimensional random waves

    NASA Astrophysics Data System (ADS)

    Taylor, Alexander J.

    2018-02-01

    The tangled nodal lines (wave vortices) in random, three-dimensional wavefields are studied as an exemplar of a fractal loop soup. Their statistics are a three-dimensional counterpart to the characteristic random behaviour of nodal domains in quantum chaos, but in three dimensions the filaments can wind around one another to give distinctly different large scale behaviours. By tracing numerically the structure of the vortices, their conformations are shown to follow recent analytical predictions for random vortex tangles with periodic boundaries, where the local disorder of the model ‘averages out’ to produce large scale power law scaling relations whose universality classes do not depend on the local physics. These results explain previous numerical measurements in terms of an explicit effect of the periodic boundaries, where the statistics of the vortices are strongly affected by the large scale connectedness of the system even at arbitrarily high energies. The statistics are investigated primarily for static (monochromatic) wavefields, but the analytical results are further shown to directly describe the reconnection statistics of vortices evolving in certain dynamic systems, or occurring during random perturbations of the static configuration.

  5. Visualizing Pure Quantum Turbulence in Superfluid 3He: Andreev Reflection and its Spectral Properties.

    PubMed

    Baggaley, A W; Tsepelin, V; Barenghi, C F; Fisher, S N; Pickett, G R; Sergeev, Y A; Suramlishvili, N

    2015-07-03

    Superfluid 3He-B in the zero-temperature limit offers a unique means of studying quantum turbulence by the Andreev reflection of quasiparticle excitations by the vortex flow fields. We validate the experimental visualization of turbulence in 3He-B by showing the relation between the vortex-line density and the Andreev reflectance of the vortex tangle in the first simulations of the Andreev reflectance by a realistic 3D vortex tangle, and comparing the results with the first experimental measurements able to probe quantum turbulence on length scales smaller than the intervortex separation.

  6. Tempo and mode of evolution in the tangled nature model.

    PubMed

    Jones, Dominic; Jensen, Henrik Jeldtoft; Sibani, Paolo

    2010-09-01

    The fossil record has been interpreted as exhibiting a gradual decrease in the extinction rate. We use the individual based Tangled Nature model of evolutionary ecology to study the mechanisms behind this kind of nonstationary macrodynamics. We demonstrate that the long time aging in the system (manifested as a slowing down of the rate of large jumps, or quakes, that the system undergoes) is related to decreasing fluctuations in the offspring probability. The scenario is reminiscent of relaxation in a quenched spin glass but purely dynamical in nature since no energy barriers can be defined.

  7. Oh what a tangled web it weaves: BRCA1 and DNA decatenation.

    PubMed

    Ashworth, Alan

    2005-08-01

    BRCA1 has significant roles in DNA repair and cell cycle checkpoint control, and is important in the maintenance of genomic stability. Defects in these pathways likely underpin the cancer susceptibility of BRCA1 mutation carriers. Now, a new function for BRCA1 in DNA decatenation--removing the tangles introduced into chromosomes as a consequence of DNA replication--is suggested in a new paper by Lou et al. (2005) in Nature Structural and Molecular Biology. Ineffective DNA decatenation may lead to chromosome breakage and inappropriate repair, adding to the roll call of defects in BRCA1 mutant cells.

  8. Holocene pollen and sediment record from the tangle lakes area, central Alaska

    USGS Publications Warehouse

    Ager, Thomas A.; Sims, John D.

    1981-01-01

    Pollen and sediments have been analyzed from a 5.5 meter‐length core of lacustrine sediments from Tangle Lakes, in the Gulkana Upland south of the Alaska Range (63 ° 01 ‘ 46”; N. latitude, 146° 03 ‘ 48 “ W. longitude). Radiocarbon ages indicate that the core spans the last 4700 years. The core sediments are sandy silt and silty clay; the core shows distinct rhythmic laminations in the lower 398 cm. The laminae appear to be normally graded; peat fibers and macerated plant debris are more abundant near the tops of the laminae. Six volcanic‐ash layers are present in the upper 110 cm of the core.Present‐day vegetation of the Tangle Lakes area is mesic shrub tundra and open spruce woodland, with scattered patches of shrub willow (Salix), balsam poplar (P. balsamifera), spruce (Picea), paper birch (Betula papyrifera), and alder (Alnus). Pollen analysis of 27 core samples suggests that this vegetation type has persisted throughout the past 4700 years, except for an apparently substantial increase in Picea beginning about 3500 years B.P. Percentages of Picea pollen are very low (generally 1–3 percent) in the lower 2 meters of core (ca. 4700 to 3500 years B.P.), but rise to 13–18 percent in the upper 3.4 meters (ca. 3500 years B.P. to present). Previously reported data from this area indicate that Picea trees initially arrived in the Tangle Lakes area about 9100 years B.P., at least 2.5 to 3 thousand years after deglaciation of the region. The present investigation suggests that Picea trees became locally scarce or died out sometime after about 9000 years B.P. but before 4700 years B.P., then reinvaded the area about 3500 years B.P. If this extrapolated age for the Picea reinvasion is accurate it suggests that local expansion of the Picea population coincides with the onset of a Neoglacial interval of cooler, moister climate. This is an unexpected result, because intervals of cooler climate generally coincide with lowering of the altitudinal limit of trees. In this case, improved moisture conditions may have promoted spruce growth and reproduction in spite of somewhat cooler temperatures.Previous pollen records from Alaska suggest that Artemisia pollen contributed little to the pollen rain of most taiga and tundra sites during Holocene time. The pollen record from Tangle Lakes, however shows rather high percentages (7–13 percent) of Artemisia deposited during the approximate time interval 4700 to 3500 years B.P. Local habitats that have well‐drained soils derived from glacial deposits support patches of Artemisia telesii and other Artemisia species. These local habitats may account for the source of Artemisiapollen deposited in the Tangle Lakes area during Holocene time.

  9. 76 FR 73667 - Notice of Inventory Completion: U.S. Department of Defense, Army Corps of Engineers, Walla Walla...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-29

    .... No known individuals were identified. The three associated funerary objects are 1 bone whistle from... associated funerary objects are 4 adze blades, 1 awl, 2 beaver incisors, 2 bone needles, 1 bone point, 1 bone toggle, 1 incised bird bone, 3 pieces of incised bone, 3 pestles, 3 polished bone items, 3 polished...

  10. Chief Information Officer > About DoD CIO > Organization > DCIO C4&IIC

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  11. Radar channel balancing with commutation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Doerry, Armin Walter

    2014-02-01

    When multiple channels are employed in a pulse-Doppler radar, achieving and maintaining balance between the channels is problematic. In some circumstances the channels may be commutated to achieve adequate balance. Commutation is the switching, trading, toggling, or multiplexing of the channels between signal paths. Commutation allows modulating the imbalance energy away from the balanced energy in Doppler, where it can be mitigated with filtering.

  12. The bacterial nanorecorder: engineering E. coli to function as a chemical recording device.

    PubMed

    Bhomkar, Prasanna; Materi, Wayne; Wishart, David S

    2011-01-01

    Synthetic biology is an emerging branch of molecular biology that uses synthetic genetic constructs to create man-made cells or organisms that are capable of performing novel and/or useful applications. Using a synthetic chemically sensitive genetic toggle switch to activate appropriate fluorescent protein indicators (GFP, RFP) and a cell division inhibitor (minC), we have created a novel E. coli strain that can be used as a highly specific, yet simple and inexpensive chemical recording device. This biological "nanorecorder" can be used to determine both the type and the time at which a brief chemical exposure event has occurred. In particular, we show that the short-term exposure (15-30 min) of cells harboring this synthetic genetic circuit to small molecule signals (anhydrotetracycline or IPTG) triggered long-term and uniform cell elongation, with cell length being directly proportional to the time elapsed following a brief chemical exposure. This work demonstrates that facile modification of an existing genetic toggle switch can be exploited to generate a robust, biologically-based "nanorecorder" that could potentially be adapted to detect, respond and record a wide range of chemical stimuli that may vary over time and space.

  13. A three-dimensional human neural cell culture model of Alzheimer's disease.

    PubMed

    Choi, Se Hoon; Kim, Young Hye; Hebisch, Matthias; Sliwinski, Christopher; Lee, Seungkyu; D'Avanzo, Carla; Chen, Hechao; Hooli, Basavaraj; Asselin, Caroline; Muffat, Julien; Klee, Justin B; Zhang, Can; Wainger, Brian J; Peitz, Michael; Kovacs, Dora M; Woolf, Clifford J; Wagner, Steven L; Tanzi, Rudolph E; Kim, Doo Yeon

    2014-11-13

    Alzheimer's disease is the most common form of dementia, characterized by two pathological hallmarks: amyloid-β plaques and neurofibrillary tangles. The amyloid hypothesis of Alzheimer's disease posits that the excessive accumulation of amyloid-β peptide leads to neurofibrillary tangles composed of aggregated hyperphosphorylated tau. However, to date, no single disease model has serially linked these two pathological events using human neuronal cells. Mouse models with familial Alzheimer's disease (FAD) mutations exhibit amyloid-β-induced synaptic and memory deficits but they do not fully recapitulate other key pathological events of Alzheimer's disease, including distinct neurofibrillary tangle pathology. Human neurons derived from Alzheimer's disease patients have shown elevated levels of toxic amyloid-β species and phosphorylated tau but did not demonstrate amyloid-β plaques or neurofibrillary tangles. Here we report that FAD mutations in β-amyloid precursor protein and presenilin 1 are able to induce robust extracellular deposition of amyloid-β, including amyloid-β plaques, in a human neural stem-cell-derived three-dimensional (3D) culture system. More importantly, the 3D-differentiated neuronal cells expressing FAD mutations exhibited high levels of detergent-resistant, silver-positive aggregates of phosphorylated tau in the soma and neurites, as well as filamentous tau, as detected by immunoelectron microscopy. Inhibition of amyloid-β generation with β- or γ-secretase inhibitors not only decreased amyloid-β pathology, but also attenuated tauopathy. We also found that glycogen synthase kinase 3 (GSK3) regulated amyloid-β-mediated tau phosphorylation. We have successfully recapitulated amyloid-β and tau pathology in a single 3D human neural cell culture system. Our unique strategy for recapitulating Alzheimer's disease pathology in a 3D neural cell culture model should also serve to facilitate the development of more precise human neural cell models of other neurodegenerative disorders.

  14. Fine tangled pili expressed by Haemophilus ducreyi are a novel class of pili.

    PubMed Central

    Brentjens, R J; Ketterer, M; Apicella, M A; Spinola, S M

    1996-01-01

    Haemophilus ducreyi synthesizes fine, tangled pili composed predominantly of a protein whose apparent molecular weight is 24,000 (24K). A hybridoma, 2D8, produced a monoclonal antibody (MAb) that bound to a 24K protein in H. ducreyi strains isolated from diverse geographic locations. A lambda gt11 H. ducreyi library was screened with MAb 2D8. A 3.5-kb chromosomal insert from one reactive plaque was amplified and ligated into the pCRII vector. The recombinant plasmid, designated pHD24, expressed a 24K protein in Escherichia coli INV alpha F that bound MAb 2D8. The coding sequence of the 24K gene was localized by exonuclease III digestion. The insert contained a 570-bp open reading frame, designated ftpA (fine, tangled pili). Translation of ftpA predicted a polypeptide with a molecular weight of 21.1K. The predicted N-terminal amino acid sequence of the polypeptide encoded by ftpA was identical to the N-terminal amino acid sequence of purified pilin and lacked a cleavable signal sequence. Primer extension analysis of ftpA confirmed the lack of a leader peptide. The predicted amino acid sequence lacked homology to known pilin sequences but shared homology with the sequences of E. coli Dps and Treponema pallidum antigen TpF1 or 4D, proteins which associate to form ordered rings. An isogenic pilin mutant, H. ducreyi 35000ftpA::mTn3(Cm), was constructed by shuttle mutagenesis and did not contain pili when examined by electron microscopy. We conclude that H. ducreyi synthesizes fine, tangled pili that are composed of a unique major subunit, which may be exported by a signal sequence independent mechanism. PMID:8550517

  15. Anisotropic Invariance and the Distribution of Quantum Correlations.

    PubMed

    Cheng, Shuming; Hall, Michael J W

    2017-01-06

    We report the discovery of two new invariants for three-qubit states which, similarly to the three-tangle, are invariant under local unitary transformations and permutations of the parties. These quantities have a direct interpretation in terms of the anisotropy of pairwise spin correlations. Applications include a universal ordering of pairwise quantum correlation measures for pure three-qubit states; trade-off relations for anisotropy, three-tangle and Bell nonlocality; strong monogamy relations for Bell inequalities, Einstein-Podolsky-Rosen steering inequalities, geometric discord and fidelity of remote state preparation (including results for arbitrary three-party states); and a statistical and reference-frame-independent form of quantum secret sharing.

  16. Cosmic microwave background polarization signals from tangled magnetic fields.

    PubMed

    Seshadri, T R; Subramanian, K

    2001-09-03

    Tangled, primordial cosmic magnetic fields create small rotational velocity perturbations on the last scattering surface of the cosmic microwave background radiation. For fields which redshift to a present value of B0 = 3 x 10(-9) G, these vector modes are shown to generate polarization anisotropies of order 0.1-4 microK on small angular scales (500

  17. Anisotropic Invariance and the Distribution of Quantum Correlations

    NASA Astrophysics Data System (ADS)

    Cheng, Shuming; Hall, Michael J. W.

    2017-01-01

    We report the discovery of two new invariants for three-qubit states which, similarly to the three-tangle, are invariant under local unitary transformations and permutations of the parties. These quantities have a direct interpretation in terms of the anisotropy of pairwise spin correlations. Applications include a universal ordering of pairwise quantum correlation measures for pure three-qubit states; trade-off relations for anisotropy, three-tangle and Bell nonlocality; strong monogamy relations for Bell inequalities, Einstein-Podolsky-Rosen steering inequalities, geometric discord and fidelity of remote state preparation (including results for arbitrary three-party states); and a statistical and reference-frame-independent form of quantum secret sharing.

  18. The role of curvature in entanglement

    NASA Astrophysics Data System (ADS)

    Buck, Gregory

    2015-10-01

    Which tangles more readily: curly hair or straight hair? A perhaps natural thought, supported by some theoretical evidence, is to associate curvature and entanglement, and assume that they would grow together-that an increase in one fosters an increase in the other. However we have biological examples such as DNA in the chromosome, and mechanical examples such as coiled telephone cords, in which much more curvature is employed than is required for the packing, and in which tangling is presumably detrimental. We offer a resolution to this conundrum. We show, that at least for simple but generally applicable models, the relationship between curvature and entanglement is subtle: if we keep filament density constant and increase curvature, the entanglement initially increases, passes through a maximum, then decreases, so there is a regime where increasing curvature increases entanglement, and there is also a regime where increasing curvature decreases entanglement. This has implications for filament packing in many circumstances, and in particular for the compaction structure of DNA in the cell-it provides a straightforward argument for the view that one purpose of DNA coiling and supercoiling is to inhibit entanglement. It also tells us to expect that wavy hair-neither the straightest nor the curliest-tangles most readily.

  19. Stochastic local operations and classical communication (SLOCC) and local unitary operations (LU) classifications of n qubits via ranks and singular values of the spin-flipping matrices

    NASA Astrophysics Data System (ADS)

    Li, Dafa

    2018-06-01

    We construct ℓ -spin-flipping matrices from the coefficient matrices of pure states of n qubits and show that the ℓ -spin-flipping matrices are congruent and unitary congruent whenever two pure states of n qubits are SLOCC and LU equivalent, respectively. The congruence implies the invariance of ranks of the ℓ -spin-flipping matrices under SLOCC and then permits a reduction of SLOCC classification of n qubits to calculation of ranks of the ℓ -spin-flipping matrices. The unitary congruence implies the invariance of singular values of the ℓ -spin-flipping matrices under LU and then permits a reduction of LU classification of n qubits to calculation of singular values of the ℓ -spin-flipping matrices. Furthermore, we show that the invariance of singular values of the ℓ -spin-flipping matrices Ω 1^{(n)} implies the invariance of the concurrence for even n qubits and the invariance of the n-tangle for odd n qubits. Thus, the concurrence and the n-tangle can be used for LU classification and computing the concurrence and the n-tangle only performs additions and multiplications of coefficients of states.

  20. Tangle-Free Finite Element Mesh Motion for Ablation Problems

    NASA Technical Reports Server (NTRS)

    Droba, Justin

    2016-01-01

    In numerical simulations involving boundaries that evolve in time, the primary challenge is updating the computational mesh to reflect the physical changes in the domain. In particular, the fundamental objective for any such \\mesh motion" scheme is to maintain mesh quality and suppress unphysical geometric anamolies and artifacts. External to a physical process of interest, mesh motion is an added component that determines the specifics of how to move the mesh given certain limited information from the main system. This paper develops a set of boundary conditions designed to eliminate tangling and internal collision within the context of PDE-based mesh motion (linear elasticity). These boundary conditions are developed for two- and three-dimensional meshes. The paper presents detailed algorithms for commonly occuring topological scenarios and explains how to apply them appropriately. Notably, the techniques discussed herein make use of none of the specifics of any particular formulation of mesh motion and thus are more broadly applicable. The two-dimensional algorithms are validated by an extensive verification procedure. Finally, many examples of diverse geometries in both two- and three-dimensions are shown to showcase the capabilities of the tangle-free boundary conditions.

  1. A mitocentric view of Alzheimer's disease suggests multi-faceted treatments.

    PubMed

    Gibson, Gary E; Shi, Qingli

    2010-01-01

    Alzheimer's disease (AD) is defined by senile plaques made of amyloid-beta peptide (Abeta), neurofibrillary tangles made of hyperphosphorylated tau proteins, and memory deficits. Thus, the events initiating the cascade leading to these end points may be more effective therapeutic targets than treating each facet individually. In the small percentage of cases of AD that are genetic (or animal models that reflect this form of AD), the factor initiating AD is clear (e.g., genetic mutations lead to high Abeta1-42 or hyperphosphorylated tau proteins). In the vast majority of AD cases, the cause is unknown. Substantial evidence now suggests that abnormalities in glucose metabolism/mitochondrial function/oxidative stress (GMO) are an invariant feature of AD and occur at an early stage of the disease process in both genetic and non-genetic forms of AD. Indeed, decreases in brain glucose utilization are diagnostic for AD. Changes in calcium homeostasis also precede clinical manifestations of AD. Abnormal GMO can lead to plaques, tangles, and the calcium abnormalities that accompany AD. Abnormalities in GMO diminish the ability of the brain to adapt. Therapies targeting mitochondria may ameliorate abnormalities in plaques, tangles, calcium homeostasis, and cognition that comprise AD.

  2. Chief Information Officer > DoDSection508 > Std_Stmt

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  3. Chief Information Officer - U.S. Department of Defense

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  4. Voice/Natural Language Interfacing for Robotic Control.

    DTIC Science & Technology

    1987-11-01

    THIS PAGE REPORT DOCUMENTATION PAGE Is. REPORT SECURITY CLASSIFICATION lb . RESTRICTIVE MARKINGS UNCLASSIFIED 2a. SECURITY CLASSIFICATION AUTHORITY 3...until major computing power can be profitably allocated to the speech recognition process, off-the- shelf units will never have sufficient intelligence to...coordinate transformation for a location, and opening or closing the gripper’s toggles. External to world operations, each joint may be rotated

  5. Walheim Troubleshoots GPC 3

    NASA Image and Video Library

    2011-07-11

    S135-E-007351 (11 July 2011) --- NASA astronaut Rex Walheim, STS-135 mission specialist, watches as astronaut Chris Ferguson (out of frame at right) toggles switches on the overhead panel of the forward flight deck of the space shuttle Atlantis. The action came during the mission's fourth day of activities in Earth orbit and second day while being docked with the International Space Station. Photo credit: NASA

  6. A Compendium of Arctic Environmental Information

    DTIC Science & Technology

    1986-03-01

    warn- ing of possible future ice invasions during petroleum drill - ing operations in open-water conditions. Development of sea ice Several basic...tubes, triple beam balance snow temperature thermistor and bridge ice ttiicl^ness hand auger, electric drill with auger, tape with toggle ice...fluids, 8 quarts daily. Acidify urine by drink- ing cranberry juice, taking Vitamin C, etc. Machines All machinery in the Arctic (engines, drills

  7. Single event effects in pulse width modulation controllers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Penzin, S.H.; Crain, W.R.; Crawford, K.B.

    1996-12-01

    SEE testing was performed on pulse width modulation (PWM) controllers which are commonly used in switching mode power supply systems. The devices are designed using both Set-Reset (SR) flip-flops and Toggle (T) flip-flops which are vulnerable to single event upset (SEU) in a radiation environment. Depending on the implementation of the different devices the effect can be significant in spaceflight hardware.

  8. Mind the GAP: A Novel Tumor-Promoting Mechanism | Center for Cancer Research

    Cancer.gov

    RAS proteins, like light switches, toggle between an “on” conformation where they promote cell growth, survival, and/or the formation of blood vessels (known as angiogenesis) and an “off” conformation in which they are unable to stimulate their target effector proteins. Nearly one-third of human tumors express a mutated RAS gene, which encodes a protein locked permanently in

  9. Enhancing poly-γ-glutamic acid production in Bacillus amyloliquefaciens by introducing the glutamate synthesis features from Corynebacterium glutamicum.

    PubMed

    Feng, Jun; Quan, Yufen; Gu, Yanyan; Liu, Fenghong; Huang, Xiaozhong; Shen, Haosheng; Dang, Yulei; Cao, Mingfeng; Gao, Weixia; Lu, Xiaoyun; Wang, Yi; Song, Cunjiang; Wang, Shufang

    2017-05-22

    Poly-γ-glutamic acid (γ-PGA) is a valuable polymer with glutamate as its sole precursor. Enhancement of the intracellular glutamate synthesis is a very important strategy for the improvement of γ-PGA production, especially for those glutamate-independent γ-PGA producing strains. Corynebacterium glutamicum has long been used for industrial glutamate production and it exhibits some unique features for glutamate synthesis; therefore introduction of these metabolic characters into the γ-PGA producing strain might lead to increased intracellular glutamate availability, and thus ultimate γ-PGA production. In this study, the unique glutamate synthesis features from C. glutamicum was introduced into the glutamate-independent γ-PGA producing Bacillus amyloliquefaciens NK-1 strain. After introducing the energy-saving NADPH-dependent glutamate dehydrogenase (NADPH-GDH) pathway, the NK-1 (pHT315-gdh) strain showed slightly increase (by 9.1%) in γ-PGA production. Moreover, an optimized metabolic toggle switch for controlling the expression of ɑ-oxoglutarate dehydrogenase complex (ODHC) was introduced into the NK-1 strain, because it was previously shown that the ODHC in C. glutamicum was completely inhibited when glutamate was actively produced. The obtained NK-PO1 (pHT01-xylR) strain showed 66.2% higher γ-PGA production than the NK-1 strain. However, the further combination of these two strategies (introducing both NADPH-GDH pathway and the metabolic toggle switch) did not lead to further increase of γ-PGA production but rather the resultant γ-PGA production was even lower than that in the NK-1 strain. We proposed new metabolic engineering strategies to improve the γ-PGA production in B. amyloliquefaciens. The NK-1 (pHT315-gdh) strain with the introduction of NADPH-GDH pathway showed 9.1% improvement in γ-PGA production. The NK-PO1 (pHT01-xylR) strain with the introduction of a metabolic toggle switch for controlling the expression of ODHC showed 66.2% higher γ-PGA production than the NK-1 strain. This work proposed a new strategy for improving the target product in microbial cell factories.

  10. A Circadian Clock-Regulated Toggle Switch Explains AtGRP7 and AtGRP8 Oscillations in Arabidopsis thaliana

    PubMed Central

    Schmal, Christoph; Reimann, Peter; Staiger, Dorothee

    2013-01-01

    The circadian clock controls many physiological processes in higher plants and causes a large fraction of the genome to be expressed with a 24h rhythm. The transcripts encoding the RNA-binding proteins AtGRP7 (Arabidopsis thaliana Glycine Rich Protein 7) and AtGRP8 oscillate with evening peaks. The circadian clock components CCA1 and LHY negatively affect AtGRP7 expression at the level of transcription. AtGRP7 and AtGRP8, in turn, negatively auto-regulate and reciprocally cross-regulate post-transcriptionally: high protein levels promote the generation of an alternative splice form that is rapidly degraded. This clock-regulated feedback loop has been proposed to act as a molecular slave oscillator in clock output. While mathematical models describing the circadian core oscillator in Arabidopsis thaliana were introduced recently, we propose here the first model of a circadian slave oscillator. We define the slave oscillator in terms of ordinary differential equations and identify the model's parameters by an optimization procedure based on experimental results. The model successfully reproduces the pertinent experimental findings such as waveforms, phases, and half-lives of the time-dependent concentrations. Furthermore, we obtain insights into possible mechanisms underlying the observed experimental dynamics: the negative auto-regulation and reciprocal cross-regulation via alternative splicing could be responsible for the sharply peaking waveforms of the AtGRP7 and AtGRP8 mRNA. Moreover, our results suggest that the AtGRP8 transcript oscillations are subordinated to those of AtGRP7 due to a higher impact of AtGRP7 protein on alternative splicing of its own and of the AtGRP8 pre-mRNA compared to the impact of AtGRP8 protein. Importantly, a bifurcation analysis provides theoretical evidence that the slave oscillator could be a toggle switch, arising from the reciprocal cross-regulation at the post-transcriptional level. In view of this, transcriptional repression of AtGRP7 and AtGRP8 by LHY and CCA1 induces oscillations of the toggle switch, leading to the observed high-amplitude oscillations of AtGRP7 mRNA. PMID:23555221

  11. Factors influencing tackle injuries in rugby union football

    PubMed Central

    Garraway, W. M.; Lee, A. J.; Macleod, D. A.; Telfer, J. W.; Deary, I. J.; Murray, G. D.

    1999-01-01

    OBJECTIVES: To assess the influence of selected aspects of lifestyle, personality, and other player related factors on injuries in the tackle. To describe the detailed circumstances in which these tackles occurred. METHODS: A prospective case-control study was undertaken in which the tackling and tackled players ("the cases") involved in a tackle injury were each matched with "control" players who held the same respective playing positions in the opposing teams. A total of 964 rugby matches involving 71 senior clubs drawn from all districts of the Scottish Rugby Union (SRU) were observed by nominated linkmen who administered self report questionnaires to the players identified as cases and controls. Information on lifestyle habits, match preparation, training, and coaching experience was obtained. A validated battery of psychological tests assessed players' trait anger and responses to anger and hostility. The circumstances of the tackles in which injury occurred were recorded by experienced SRU coaching staff in interviews with involved players after the match. RESULTS: A total of 71 tackle injury episodes with correct matching of cases and controls were studied. The following player related factors did not contribute significantly to tackle injuries: alcohol consumption before the match, feeling "below par" through minor illness, the extent of match preparation, previous coaching, or practising tackling. Injured and non- injured players in the tackle did not differ in their disposition toward, or expression of, anger or hostility. Some 85% of tackling players who were injured were three quarters, and 52% of injuries occurred when the tackle came in behind the tackled player or within his peripheral vision. Either the tackling or tackled player was sprinting or running in all of these injury episodes. One third of injuries occurred in differential speed tackles--that is, when one player was travelling much faster than the other at impact. The player with the lower momentum was injured in 80% of these cases. Forceful or crunching tackles resulting in injury mostly occurred head on or within the tackled player's side vision. CONCLUSIONS: Attention should be focused on high speed tackles going in behind the tackled player's line of vision. Comparative information on the circumstances of the vast majority of tackles in which no injury occurs is required before any changes are considered to reduce injuries in the tackle. 


 PMID:10027056

  12. 3D printed cat tongue is a self-cleaning, tangle-teasing brush

    NASA Astrophysics Data System (ADS)

    Noel, Alexis; Hu, David

    A cat's tongue is covered in an array of spines called papillae. These spines are thought to be used in grooming and rasping meat from bones of prey, although no mechanism has been given. We use high-speed video to film a cat grooming. We show that the spines on the tongue act as low pass filters for tangles in hair. The tongue itself is highly elastic, while the spines are rigid. We 3D print a cat tongue mimic and show that the nonlinear force applied by the spines helps to increase efficacy of grooming. The tongue also provides frictional anisotropy with backward-facing spines, allowing for self-cleaning properties post-groom.

  13. Non-sanctioning of illegal tackles in South African youth community rugby.

    PubMed

    Brown, J C; Boucher, S J; Lambert, M; Viljoen, W; Readhead, C; Hendricks, S; Kraak, W J

    2018-06-01

    The tackle event in rugby union ('rugby') contributes to the majority of players' injuries. Referees can reduce this risk by sanctioning dangerous tackles. A study in elite adult rugby suggests that referees only sanction a minority of illegal tackles. The aim of this study was to assess if this finding was similar in youth community rugby. Observational study. Using EncodePro, 99 South African Rugby Union U18 Youth Week tournament matches were coded between 2011 and 2015. All tackles were coded by a researcher and an international referee to ensure that laws were interpreted correctly. The inter- and intra-rater reliabilities were 0.97-1.00. A regression analysis compared the non-sanctioned rates over time. In total, 12 216 tackles were coded, of which less than 1% (n=113) were 'illegal'. The majority of the 113 illegal tackles were front-on (75%), high tackles (72%) and occurred in the 2nd/4th quarters (29% each). Of the illegal tackles, only 59% were sanctioned. The proportions of illegal tackles and sanctioning of these illegal tackles to all tackles improved by 0.2% per year from 2011-2015 (p<0.05). In these youth community rugby players, 59% of illegal tackles were not sanctioned appropriately. This was better than a previous study in elite adult rugby, where only 7% of illegal tackles were penalised. Moreover, the rates of illegal tackles and non-sanctioned illegal tackles both improved over time. However, it is critical that referees consistently enforce all laws to enhance injury prevention efforts. Further studies should investigate the reasons for non-sanctioning. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  14. Chief Information Officer > About DoD CIO > Organization > DCIO CS

    Science.gov Websites

    Skip to main content (Press Enter). Toggle navigation Chief Information Officer Search Search Chief Information Officer: Search Search Chief Information Officer: Search Chief Information Officer U.S. Department of Defense Chief Information Officer Home About DoD CIO Bios Organization DCIO C4&IIC DCIO IE

  15. Influenza (Flu) | North Carolina Department of Health and Human Services

    Science.gov Websites

    Toggle navigation Home Statistics Providers FAQs Information Contact Don't Be a Shot Dodger! Meet , the flu knocks everyone off their game. Don't be a Shot Dodger! Contact your health care provider or Clinicians (PDF, 31KB) - UPDATED 09/27/17 Novel Influenza Information N.C. Memo to Clinicians on Influenza A

  16. Robotic Vehicle Communications Interoperability

    DTIC Science & Technology

    1988-08-01

    starter (cold start) X X Fire suppression X Fording control X Fuel control X Fuel tank selector X Garage toggle X Gear selector X X X X Hazard warning...optic Sensors Sensor switch Video Radar IR Thermal imaging system Image intensifier Laser ranger Video camera selector Forward Stereo Rear Sensor control...optic sensors Sensor switch Video Radar IR Thermal imaging system Image intensifier Laser ranger Video camera selector Forward Stereo Rear Sensor

  17. Fermilab | Science | Questions for the Universe | The Particle World | What

    Science.gov Websites

    is dark matter? How can we make it in the laboratory? Fermilab Search Toggle Fermilab Navbar Fermilab and the LHC Dark matter and dark energy ADMX Muons More fundamental particles and forces Theory there so many kinds of particles? What is dark matter? How can we make it in the laboratory? What are

  18. Tackle mechanisms and match characteristics in women's elite football tournaments.

    PubMed

    Tscholl, P; O'Riordan, D; Fuller, C W; Dvorak, J; Junge, A

    2007-08-01

    Several tools have been used for assessing risk situations and for gathering tackle information from international football matches for men but not for women. To analyse activities in women's football and to identify the characteristics and risk potentials of tackles. Retrospective video analysis. Video recordings of 24 representative matches from six women's top-level tournaments were analysed for tackle parameters and their risk potential. 3531 tackles were recorded. Tackles in which the tackling player came from the side and stayed on her feet accounted for nearly half of all challenges for the ball in which body contact occurred. 2.7% of all tackles were classified as risk situations, with sliding-in tackles from behind and the side having the highest risk potential. Match referees sanctioned sliding-in tackles more often than other tackles (20% v 17%, respectively). Tackle parameters did not change in the duration of a match; however, there was an increase in the number of injury risk situations and foul plays towards the end of each half. Match properties provide valuable information for a better understanding of injury situations in football. Staying on feet and jumping vertically tackle actions leading to injury were sanctioned significantly more times by the referee than those not leading to injury (p<0.001), but no such difference was seen for sliding-in tackles (previously reported to have the highest injury potential in women's football). Therefore, either the laws of the game are not adequate or match referees in women's football are not able to distinguish between sliding-in tackles leading to and those not leading to injury.

  19. Correlation of Alzheimer Disease Neuropathologic Changes With Cognitive Status: A Review of the Literature

    PubMed Central

    Nelson, Peter T.; Alafuzoff, Irina; Bigio, Eileen H.; Bouras, Constantin; Braak, Heiko; Cairns, Nigel J.; Castellani, Rudolph J.; Crain, Barbara J.; Davies, Peter; Del Tredici, Kelly; Duyckaerts, Charles; Frosch, Matthew P.; Haroutunian, Vahram; Hof, Patrick R.; Hulette, Christine M.; Hyman, Bradley T.; Iwatsubo, Takeshi; Jellinger, Kurt A.; Jicha, Gregory A.; Kövari, Enikö; Kukull, Walter A.; Leverenz, James B.; Love, Seth; Mackenzie, Ian R.; Mann, David M.; Masliah, Eliezer; McKee, Ann C.; Montine, Thomas J.; Morris, John C.; Schneider, Julie A.; Sonnen, Joshua A.; Thal, Dietmar R.; Trojanowski, John Q.; Troncoso, Juan C.; Wisniewski, Thomas; Woltjer, Randall L.; Beach, Thomas G.

    2013-01-01

    Clinicopathologic correlation studies are critically important for the field of Alzheimer disease (AD) research. Studies on human subjects with autopsy confirmation entail numerous potential biases that affect both their general applicability and the validity of the correlations. Many sources of data variability can weaken the apparent correlation between cognitive status and AD neuropathologic changes. Indeed, most persons in advanced old age have significant non-AD brain lesions that may alter cognition independently of AD. Worldwide research efforts have evaluated thousands of human subjects to assess the causes of cognitive impairment in the elderly, and these studies have been interpreted in different ways. We review the literature focusing on the correlation of AD neuropathologic changes (i.e. β-amyloid plaques and neurofibrillary tangles) with cognitive impairment. We discuss the various patterns of brain changes that have been observed in elderly individuals to provide a perspective for understanding AD clinicopathologic correlation and conclude that evidence from many independent research centers strongly supports the existence of a specific disease, as defined by the presence of Aβ plaques and neurofibrillary tangles. Although Aβ plaques may play a key role in AD pathogenesis, the severity of cognitive impairment correlates best with the burden of neocortical neurofibrillary tangles. PMID:22487856

  20. Indexing and retrieving motions of characters in close contact.

    PubMed

    Ho, Edmond S L; Komura, Taku

    2009-01-01

    Human motion indexing and retrieval are important for animators due to the need to search for motions in the database which can be blended and concatenated. Most of the previous researches of human motion indexing and retrieval compute the Euclidean distance of joint angles or joint positions. Such approaches are difficult to apply for cases in which multiple characters are closely interacting with each other, as the relationships of the characters are not encoded in the representation. In this research, we propose a topology-based approach to index the motions of two human characters in close contact. We compute and encode how the two bodies are tangled based on the concept of rational tangles. The encoded relationships, which we define as TangleList, are used to determine the similarity of the pairs of postures. Using our method, we can index and retrieve motions such as one person piggy-backing another, one person assisting another in walking, and two persons dancing / wrestling. Our method is useful to manage a motion database of multiple characters. We can also produce motion graph structures of two characters closely interacting with each other by interpolating and concatenating topologically similar postures and motion clips, which are applicable to 3D computer games and computer animation.

  1. Abnormal tau phosphorylation in the thorny excrescences of CA3 hippocampal neurons in patients with Alzheimer's disease.

    PubMed

    Blazquez-Llorca, Lidia; Garcia-Marin, Virginia; Merino-Serrais, Paula; Ávila, Jesús; DeFelipe, Javier

    2011-01-01

    A key symptom in the early stages of Alzheimer's disease (AD) is the loss of declarative memory. The anatomical substrate that supports this kind of memory involves the neural circuits of the medial temporal lobe, and in particular, of the hippocampal formation and adjacent cortex. A main feature of AD is the abnormal phosphorylation of the tau protein and the presence of tangles. The sequence of cellular changes related to tau phosphorylation and tangle formation has been studied with an antibody that binds to diffuse phosphotau (AT8). Moreover, another tau antibody (PHF-1) has been used to follow the pathway of neurofibrillary (tau aggregation) degeneration in AD. We have used a variety of quantitative immunocytochemical techniques and confocal microscopy to visualize and characterize neurons labeled with AT8 and PHF-1 antibodies. We present here the rather unexpected discovery that in AD, there is conspicuous abnormal phosphorylation of the tau protein in a selective subset of dendritic spines. We identified these spines as the typical thorny excrescences of hippocampal CA3 neurons in a pre-tangle state. Since thorny excrescences represent a major synaptic target of granule cell axons (mossy fibers), such aberrant phosphorylation may play an essential role in the memory impairment typical of AD patients.

  2. Plastic Deformation Behavior of Ti Foil Under Ultrasonic Vibration in Tension

    NASA Astrophysics Data System (ADS)

    Jiang, Shaosong; Jia, Yong; Zhang, Hongbin; Du, Zhihao; Lu, Zhen; Zhang, Kaifeng; He, Yushi; Wang, Ruizhuo

    2017-04-01

    The benefits of ultrasonic vibration auxiliary metal forming have been shown by many studies. In this study, a series of experiments were carried out to investigate the deformation behavior of Ti foils under ultrasonic vibration in tension, and the tensile properties of Ti foils with/without the application of ultrasonic vibration were investigated. Then, the microstructure of different tensile samples was analyzed by transmission electron microscopy (TEM). The results of the tensile experiments showed that the tensile strength of tensile samples was reduced when ultrasonic vibration was applied, while the elongation of these samples increased. The flow stress increased with increasing strain without applying ultrasonic vibration, while it decreased steeply when the ultrasonic vibration was applied, and this reduction of flow stress demonstrated the effect of acoustic softening on the properties of the material. Additionally, the range of flow stress reduction was inversely proportional to the time for which ultrasonic vibration was applied. The TEM images showed that there were remarkable differences in dislocation distribution and tangles with/without ultrasonic vibration. The dislocation distribution was inhomogeneous, and copious dislocation tangles were discovered without ultrasonic vibration. When it was applied, the parallel re-arrangement of dislocations could be observed and the mass of dislocation tangles was mostly absent.

  3. Tangle-Free Mesh Motion for Ablation Simulations

    NASA Technical Reports Server (NTRS)

    Droba, Justin

    2016-01-01

    Problems involving mesh motion-which should not be mistakenly associated with moving mesh methods, a class of adaptive mesh redistribution techniques-are of critical importance in numerical simulations of the thermal response of melting and ablative materials. Ablation is the process by which material vaporizes or otherwise erodes due to strong heating. Accurate modeling of such materials is of the utmost importance in design of passive thermal protection systems ("heatshields") for spacecraft, the layer of the vehicle that ensures survival of crew and craft during re-entry. In an explicit mesh motion approach, a complete thermal solve is first performed. Afterwards, the thermal response is used to determine surface recession rates. These values are then used to generate boundary conditions for an a posteriori correction designed to update the location of the mesh nodes. Most often, linear elastic or biharmonic equations are used to model this material response, traditionally in a finite element framework so that complex geometries can be simulated. A simple scheme for moving the boundary nodes involves receding along the surface normals. However, for all but the simplest problem geometries, evolution in time following such a scheme will eventually bring the mesh to intersect and "tangle" with itself, inducing failure. This presentation demonstrates a comprehensive and sophisticated scheme that analyzes the local geometry of each node with help from user-provided clues to eliminate the tangle and enable simulations on a wide-class of difficult problem geometries. The method developed is demonstrated for linear elastic equations but is general enough that it may be adapted to other modeling equations. The presentation will explicate the inner workings of the tangle-free mesh motion algorithm for both two and three-dimensional meshes. It will show abstract examples of the method's success, including a verification problem that demonstrates its accuracy and correctness. The focus of the presentation will be on the algorithm; specifics on how the techniques may be used in spacecraft design will be not discussed.

  4. At-vessel mortality of skates (Rajidae) taken in coastal fisheries and evidence of longer-term survival.

    PubMed

    Ellis, J R; Burt, G J; Grilli, G; McCully Phillips, S R; Catchpole, T L; Maxwell, D L

    2018-06-01

    Data on the vigour and at-vessel mortality (AVM) of 6798 skates (comprising Raja clavata n = 6295; R. brachyura n = 208; R. undulata n = 185, R. montagui n = 98 and R. microocellata n = 12) captured by commercial fishing vessels in the inshore waters of the southern North Sea and English Channel were recorded. AVM in longline fisheries averaged 0·44% across five vessels (0-1·47%), although skates were usually unhooked manually and did not usually pass through a bait-stripper. AVM in otter trawls averaged 0·76% (0-2·35%), from four vessels fishing with tow durations of <1·5 h (southern North Sea) or 1-4 h (English Channel). No AVM was noted for skates taken as a by-catch in drift trammel nets (soak times <4 h). Anchored tangle nets resulted in an overall AVM of 2·0-2·7%, but increased from 1·47% (13-28 h soak time) to 6·16% (42-53 h soak time). There were significant differences in the vigour of skates between gears, with R. clavata caught by longline and tangle nets in better condition than those captured by otter trawl or drift trammel net. Similarly, R. undulata caught by tangle net were in better condition than those caught by otter trawl. The vigour of R. undulata was also found to be higher than other skate species for both trawl and tangle net. In total, 5283 skates were tagged with Petersen discs and released, with recapture rates for the various combinations of vessel and gear ranging up to 24·8% for R. clavata. Whilst confirming a degree of post-release survival, quantitative estimates of post-release mortality for skates remain unknown. © 2018 Crown Copyright. Journal of Fish Biology © 2018 The Fisheries Society of the British Isles.

  5. [F-18]-AV-1451 binding correlates with postmortem neurofibrillary tangle Braak staging.

    PubMed

    Marquié, Marta; Siao Tick Chong, Michael; Antón-Fernández, Alejandro; Verwer, Eline E; Sáez-Calveras, Nil; Meltzer, Avery C; Ramanan, Prianca; Amaral, Ana C; Gonzalez, Jose; Normandin, Marc D; Frosch, Matthew P; Gómez-Isla, Teresa

    2017-10-01

    [F-18]-AV-1451, a PET tracer specifically developed to detect brain neurofibrillary tau pathology, has the potential to facilitate accurate diagnosis of Alzheimer's disease (AD), staging of brain tau burden and monitoring disease progression. Recent PET studies show that patients with mild cognitive impairment and AD dementia exhibit significantly higher in vivo [F-18]-AV-1451 retention than cognitively normal controls. Importantly, PET patterns of [F-18]-AV-1451 correlate well with disease severity and seem to match the predicted topographic Braak staging of neurofibrillary tangles (NFTs) in AD, although this awaits confirmation. We studied the correlation of autoradiographic binding patterns of [F-18]-AV-1451 and the stereotypical spatiotemporal pattern of progression of NFTs using legacy postmortem brain samples representing different Braak NFT stages (I-VI). We performed [F-18]-AV-1451 phosphor-screen autoradiography and quantitative tau measurements (stereologically based NFT counts and biochemical analysis of tau pathology) in three brain regions (entorhinal cortex, superior temporal sulcus and visual cortex) in a total of 22 cases: low Braak (I-II, n = 6), intermediate Braak (III-IV, n = 7) and high Braak (V-VI, n = 9). Strong and selective [F-18]-AV-1451 binding was detected in all tangle-containing regions matching precisely the observed pattern of PHF-tau immunostaining across the different Braak stages. As expected, no signal was detected in the white matter or other non-tangle containing regions. Quantification of [F-18]-AV-1451 binding was very significantly correlated with the number of NFTs present in each brain region and with the total tau and phospho-tau content as reported by Western blot and ELISA. [F-18]-AV-1451 is a promising biomarker for in vivo quantification of brain tau burden in AD. Neuroimaging-pathologic studies conducted on postmortem material from individuals imaged while alive are now needed to confirm these observations.

  6. A sequence of cytoskeleton changes related to the formation of neurofibrillary tangles and neuropil threads.

    PubMed

    Braak, E; Braak, H; Mandelkow, E M

    1994-01-01

    Frontal sections of the temporal lobe including the transentorhinal/entorhinal region, amygdala, and/or hippocampus from human adult brains are studied for cytoskeleton changes using immunostaining with the antibodies AT8 and Alz-50 and selective silver impregnation methods for neurofibrillary changes of the Alzheimer type. For the purpose of correlation, the two methods are carried out one after the other on the same section. Layer pre-alpha in the transentorhinal/entorhinal region harbours nerve cells which are among the first nerve cells in the entire brain to show the development of neurofibrillary changes. This presents the opportunity for study of both early events in the destruction of the cytoskeleton in individual neurons, and to relate changes which occur in the neuronal processes in the absence of alterations in their immediate surroundings to those happening in the soma. Immunoreactions with the AT8 antibody in particular reveal a clear sequence of changes in the neuronal cytoskeleton. Group 1 neurons present initial cytoskeleton changes in that the soma, dendrites, and axon are completely marked by granular AT8 immunoreactive material. These neurons appear quite normal and turn out to be devoid of argyrophilic material when observed in silver-stained sections. Group 2 neurons show changes in the cellular processes. The terminal tuft of the apical dendrite is replaced by tortuous varicose fibres and coarse granules. The distal portions of the dendrites are curved and show appendages and thickened portions. Intensely homogeneously immunostained rod-like inclusions are encountered in these thickened portions and in the soma. A number of these rod-like inclusions are visible after silver staining, as well. Group 3 neurons display even more pronounced alterations of their distal--most dendritic portions. The intermediate dendritic parts lose immunoreactivity, but the soma is homogeneously immunostained. Silver staining reveals in most of the distal dendritic parts neuropil threads, and in the soma a classic neurofibrillary tangle. Group 4 structures are marked by accumulations of coarse AT8-immunoreactive granules. Silver staining provides evidence that the fibrillary material has become an extraneuronal, "early" ghost tangle. Finally, group 5 structures present "late" ghost tangles in silver-stained sections but fail to demonstrate AT8 immunoreactivity. It is suggested that the altered tau protein shown by the antibody AT8 represents an early cytoskeleton change which eventually leads to the formation of argyrophilic neurofibrillary tangles and neuropil threads.

  7. Tackle and impact detection in elite Australian football using wearable microsensor technology.

    PubMed

    Gastin, Paul B; McLean, Owen C; Breed, Ray V P; Spittle, Michael

    2014-01-01

    The effectiveness of a wearable microsensor device (MinimaxX(TM) S4, Catapult Innovations, Melbourne, VIC, Australia) to automatically detect tackles and impact events in elite Australian football (AF) was assessed during four matches. Video observation was used as the criterion measure. A total of 352 tackles were observed, with 78% correctly detected as tackles by the manufacturer's software. Tackles against (i.e. tackled by an opponent) were more accurately detected than tackles made (90% v 66%). Of the 77 tackles that were not detected at all, the majority (74%) were categorised as low-intensity. In contrast, a total of 1510 "tackle" events were detected, with only 18% of these verified as tackles. A further 57% were from contested ball situations involving player contact. The remaining 25% were in general play where no contact was evident; these were significantly lower in peak Player Load™ than those involving player contact (P < 0.01). The tackle detection algorithm, developed primarily for rugby, was not suitable for tackle detection in AF. The underlying sensor data may have the potential to detect a range of events within contact sports such as AF, yet to do so is a complex task and requires sophisticated sport and event-specific algorithms.

  8. ApoE and Sex Bias in Cerebrovascular Aging of Men and Mice

    PubMed Central

    Finch, Caleb E.; Shams, Sara

    2016-01-01

    Alzheimer disease (AD) research has mainly focused on neurodegenerative processes associated with the classic neuropathologic markers of senile plaques and neurofibrillary tangles. Additionally, cerebrovascular contributions to dementia are increasingly recognized, particularly from cerebral small vessel disease (SVD). Remarkably, in AD brains, the ApoE ε4 allele shows male excess for cerebral microbleeds (CMB), a marker of SVD, which is opposite to the female excess of plaques and tangles. Mouse transgenic models add further complexities to sex-ApoE ε4 allele interactions, with female excess of CMBs and brain amyloid. We conclude that brain aging and AD pathogenesis cannot be understood in humans without addressing major gaps in the extent of sex differences in cerebrovascular pathology. PMID:27546867

  9. Distribution of lead in the brain tissues from DNTC patients using synchrotron radiation microbeams

    NASA Astrophysics Data System (ADS)

    Ide-Ektessabi, Ari; Ota, Yukihide; Ishihara, Ryoko; Mizuno, Yutaka; Takeuchi, Tohru

    2005-12-01

    Diffuse neurofibrillary tangles with calcification (DNTC) is a form of dementia with certain characteristics. Its pathology is characterized by cerebrum atrophy, calcification on globus pallidus and dentate nucleus and diffuse neurofibrillary tangles without senile plaques. In the present study brain tissues were prepared from patients with patients DNTC, calcified and non-calcified Alzheimer's disease (AD) patients. The brain tissues were examined non-destructively by X-ray fluorescence (XRF) spectroscopy using synchrotron radiation (SR) microbeams for trace metallic elements Ca, Fe, Cu, Zn and Pb. The XRF analysis showed that there were Pb concentrations in the calcified areas in the brain tissues with both DNTC and AD but there was none in those with non-calcified AD.

  10. Phylogenetic tree and community structure from a Tangled Nature model.

    PubMed

    Canko, Osman; Taşkın, Ferhat; Argın, Kamil

    2015-10-07

    In evolutionary biology, the taxonomy and origination of species are widely studied subjects. An estimation of the evolutionary tree can be done via available DNA sequence data. The calculation of the tree is made by well-known and frequently used methods such as maximum likelihood and neighbor-joining. In order to examine the results of these methods, an evolutionary tree is pursued computationally by a mathematical model, called Tangled Nature. A relatively small genome space is investigated due to computational burden and it is found that the actual and predicted trees are in reasonably good agreement in terms of shape. Moreover, the speciation and the resulting community structure of the food-web are investigated by modularity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Time-dependent extinction rate and species abundance in a tangled-nature model of biological evolution.

    PubMed

    Hall, Matt; Christensen, Kim; di Collobiano, Simone A; Jensen, Henrik Jeldtoft

    2002-07-01

    We present a model of evolutionary ecology consisting of a web of interacting individuals, a tangle-nature model. The reproduction rate of individuals characterized by their genome depends on the composition of the population in genotype space. Ecological features such as the taxonomy and the macroevolutionary mode of the dynamics are emergent properties. The macrodynamics exhibit intermittent two-mode switching with a gradually decreasing extinction rate. The generated ecologies become gradually better adapted as well as more complex in a collective sense. The form of the species abundance curve compares well with observed functional forms. The model's error threshold can be understood in terms of the characteristics of the two dynamical modes of the system.

  12. Negativity and strong monogamy of multiparty quantum entanglement beyond qubits

    NASA Astrophysics Data System (ADS)

    Choi, Jin Hyuk; Kim, Jeong San

    2015-10-01

    We propose the square of convex-roof extended negativity (SCREN) as a powerful candidate to characterize strong monogamy of multiparty quantum entanglement. We first provide a strong monogamy inequality of multiparty entanglement using SCREN and show that the tangle-based multiqubit strong-monogamy inequality can be rephrased by SCREN. We further show that the SCREN strong-monogamy inequality is still true for the counterexamples that violate tangle-based the strong-monogamy inequality in higher-dimensional quantum systems other than qubits. We also analytically show that SCREN strong-monogamy inequality is true for a large class of multiqudit states, a superposition of multiqudit generalized W -class states and vacuums. Thus SCREN is a good alternative to characterize the strong monogamy of entanglement even in multiqudit systems.

  13. Tackler’s head position relative to the ball carrier is highly correlated with head and neck injuries in rugby

    PubMed Central

    Hasegawa, Yoshinori; Shiota, Yuki; Ota, Chihiro; Yoneda, Takeshi; Tahara, Shigeyuki; Maki, Nobukazu; Matsuura, Takahiro; Sekiguchi, Masahiro; Itoigawa, Yoshiaki; Tateishi, Tomohiko; Kaneko, Kazuo

    2018-01-01

    Objectives To characterise the tackler’s head position during one-on-one tackling in rugby and to determine the incidence of head, neck and shoulder injuries through analysis of game videos, injury records and a questionnaire completed by the tacklers themselves. Methods We randomly selected 28 game videos featuring two university teams in competitions held in 2015 and 2016. Tackles were categorised according to tackler’s head position. The ‘pre-contact phase’ was defined; its duration and the number of steps taken by the ball carrier prior to a tackle were evaluated. Results In total, 3970 tackles, including 317 (8.0%) with the tackler’s head incorrectly positioned (ie, in front of the ball carrier) were examined. Thirty-two head, neck or shoulder injuries occurred for an injury incidence of 0.8% (32/3970). The incidence of injury in tackles with incorrect head positioning was 69.4/1000 tackles; the injury incidence with correct head positioning (ie, behind or to one side of the ball carrier) was 2.7/1000 tackles. Concussions, neck injuries, ‘stingers’ and nasal fractures occurred significantly more often during tackles with incorrect head positioning than during tackles with correct head positioning. Significantly fewer steps were taken before tackles with incorrect head positioning that resulted in injury than before tackles that did not result in injury. Conclusion Tackling with incorrect head position relative to the ball carrier resulted in a significantly higher incidence of concussions, neck injuries, stingers and nasal fractures than tackling with correct head position. Tackles with shorter duration and distance before contact resulted in more injuries. PMID:29162618

  14. Tackle characteristics and injury in a cross section of rugby union football.

    PubMed

    McIntosh, Andrew S; Savage, Trevor N; McCrory, Paul; Fréchède, Bertrand O; Wolfe, Rory

    2010-05-01

    The tackle is the game event in rugby union most associated with injury. This study's main aims were to measure tackle characteristics from video using a qualitative protocol, to assess whether the characteristics differed by level of play, and to measure the associations between tackle characteristics and injury. A cohort study was undertaken. The cohort comprised male rugby players in the following levels: younger than 15 yr, 18 yr, and 20 yr, grade, and elite (Super 12 and Wallabies). All tackle events and technique characteristics were coded in 77 game halves using a standardized qualitative protocol. Game injuries and missed-game injuries were identified and correlated with tackle events. A total of 6618 tackle events, including 81 resulting in a game injury, were observed and coded in the 77 game halves fully analyzed (145 tackle events per hour). An increase in the proportion of active shoulder tackles was observed from younger than 15 yr (13%) to elite (31%). Younger players engaged in more passive tackles and tended to stay on their feet more than experienced players. Younger than 15 yr rugby players had a significantly lower risk of tackle game injury compared with elite players. No specific tackle technique was observed to be associated with a significantly increased risk of game injury. There was a greater risk of game injury associated with two or more tacklers involved in the tackle event, and the greatest risk was associated with simultaneous contact by tacklers, after adjusting for level of play. Tackle characteristics differed between levels of play. The number of tacklers and the sequence of tackler contact with the ball carrier require consideration from an injury prevention perspective.

  15. 46 CFR 184.300 - Ground tackle and mooring lines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Ground tackle and mooring lines. 184.300 Section 184.300... Ground tackle and mooring lines. A vessel must be fitted with ground tackle and mooring lines necessary for the vessel to be safely anchored or moored. The ground tackle and mooring lines provided must be...

  16. 46 CFR 184.300 - Ground tackle and mooring lines.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Ground tackle and mooring lines. 184.300 Section 184.300... Ground tackle and mooring lines. A vessel must be fitted with ground tackle and mooring lines necessary for the vessel to be safely anchored or moored. The ground tackle and mooring lines provided must be...

  17. Stability and Multiattractor Dynamics of a Toggle Switch Based on a Two-Stage Model of Stochastic Gene Expression

    PubMed Central

    Strasser, Michael; Theis, Fabian J.; Marr, Carsten

    2012-01-01

    A toggle switch consists of two genes that mutually repress each other. This regulatory motif is active during cell differentiation and is thought to act as a memory device, being able to choose and maintain cell fate decisions. Commonly, this switch has been modeled in a deterministic framework where transcription and translation are lumped together. In this description, bistability occurs for transcription factor cooperativity, whereas autoactivation leads to a tristable system with an additional undecided state. In this contribution, we study the stability and dynamics of a two-stage gene expression switch within a probabilistic framework inspired by the properties of the Pu/Gata toggle switch in myeloid progenitor cells. We focus on low mRNA numbers, high protein abundance, and monomeric transcription-factor binding. Contrary to the expectation from a deterministic description, this switch shows complex multiattractor dynamics without autoactivation and cooperativity. Most importantly, the four attractors of the system, which only emerge in a probabilistic two-stage description, can be identified with committed and primed states in cell differentiation. To begin, we study the dynamics of the system and infer the mechanisms that move the system between attractors using both the quasipotential and the probability flux of the system. Next, we show that the residence times of the system in one of the committed attractors are geometrically distributed. We derive an analytical expression for the parameter of the geometric distribution, therefore completely describing the statistics of the switching process and elucidate the influence of the system parameters on the residence time. Moreover, we find that the mean residence time increases linearly with the mean protein level. This scaling also holds for a one-stage scenario and for autoactivation. Finally, we study the implications of this distribution for the stability of a switch and discuss the influence of the stability on a specific cell differentiation mechanism. Our model explains lineage priming and proposes the need of either high protein numbers or long-term modifications such as chromatin remodeling to achieve stable cell fate decisions. Notably, we present a system with high protein abundance that nevertheless requires a probabilistic description to exhibit multistability, complex switching dynamics, and lineage priming. PMID:22225794

  18. Examination of the Clinicopathologic Continuum of Alzheimer Disease in the Autopsy Cohort of the National Alzheimer Coordinating Center

    PubMed Central

    Serrano-Pozo, Alberto; Qian, Jing; Monsell, Sarah E.; Frosch, Matthew P.; Betensky, Rebecca A.; Hyman, Bradley T.

    2014-01-01

    To test the hypothesis that Alzheimer disease (AD) is a clinical and pathologic continuum between normal aging and end-stage dementia, we selected a convenience sample of subjects from the National Alzheimer Coordinating Center 2005 to 2012 autopsy cohort (n = 2,083) with the last clinical evaluation within 2 years before autopsy and no other primary neuropathologic diagnosis. Demographic and neuropathologic characteristics were correlated with the Clinical Dementia Rating–Sum of Boxes in the 835 subjects meeting these criteria. Both neuritic plaques and neurofibrillary tangles independently predicted Clinical Dementia Rating–Sum of Boxes. Severe small-vessel disease, severe amyloid angiopathy, and hippocampal sclerosis were also independently associated with the degree of cognitive impairment. By contrast, education was a strong independent protective factor against cognitive deficits. The cause of mild to moderate dementia remained uncertain in 14% of the patients. Inverse probability weighting suggests the generalizability of these results to nonautopsied cohorts. These data indicate that plaques and tangles independently contribute to cognitive impairment, that concurrent vascular disease strongly correlates with cognitive dysfunction even in a sample selected to represent the AD pathologic continuum, and that education further modifies clinical expression. Thus, multiple concomitant etiologies of brain damage and premorbid characteristics contribute to the uncertainty of AD clinicopathologic correlations based only on tangles and plaques. PMID:24226270

  19. Association of Cancer History with Alzheimer's Disease Dementia and Neuropathology.

    PubMed

    Yarchoan, Mark; James, Bryan D; Shah, Raj C; Arvanitakis, Zoe; Wilson, Robert S; Schneider, Julie; Bennett, David A; Arnold, Steven E

    2017-01-01

    Cancer and Alzheimer's disease (AD) are common diseases of aging and share many risk factors. Surprisingly, however, epidemiologic data from several recent independent cohort studies suggest that there may be an inverse association between these diseases. To determine the relationship between history of cancer and odds of dementia proximate to death and neuropathological indices of AD. Using data from two separate clinical-pathologic cohort studies of aging and AD, the Religious Orders Study (ROS) and the Rush Memory and Aging Project (MAP), we compared odds of AD dementia proximate to death among participants with and without a history of cancer. We then examined the relation of history of cancer with measures of AD pathology at autopsy, i.e., paired helical filament tau (PHFtau) neurofibrillary tangles and amyloid-β load. Participants reporting a history of cancer had significantly lower odds of AD (OR 0.70 [0.55-0.89], p = 0.0040) proximate to death as compared to participants reporting no prior history of cancer. The results remained significant after adjusting for multiple risk factors including age, sex, race, education, and presence of an APOEɛ4 allele. At autopsy, participants with a history of cancer had significantly fewer PHFtau tangles (p < 0.001) than participants without a history of cancer, but similar levels of amyloid-β. Cancer survivors have reduced odds of developing AD and a lower burden of neurofibrillary tangle deposition.

  20. Examination of the clinicopathologic continuum of Alzheimer disease in the autopsy cohort of the National Alzheimer Coordinating Center.

    PubMed

    Serrano-Pozo, Alberto; Qian, Jing; Monsell, Sarah E; Frosch, Matthew P; Betensky, Rebecca A; Hyman, Bradley T

    2013-12-01

    To test the hypothesis that Alzheimer disease (AD) is a clinical and pathologic continuum between normal aging and end-stage dementia, we selected a convenience sample of subjects from the National Alzheimer Coordinating Center 2005 to 2012 autopsy cohort (n = 2,083) with the last clinical evaluation within 2 years before autopsy and no other primary neuropathologic diagnosis. Demographic and neuropathologic characteristics were correlated with the Clinical Dementia Rating-Sum of Boxes in the 835 subjects meeting these criteria. Both neuritic plaques and neurofibrillary tangles independently predicted Clinical Dementia Rating-Sum of Boxes. Severe small-vessel disease, severe amyloid angiopathy, and hippocampal sclerosis were also independently associated with the degree of cognitive impairment. By contrast, education was a strong independent protective factor against cognitive deficits. The cause of mild to moderate dementia remained uncertain in 14% of the patients. Inverse probability weighting suggests the generalizability of these results to nonautopsied cohorts. These data indicate that plaques and tangles independently contribute to cognitive impairment, that concurrent vascular disease strongly correlates with cognitive dysfunction even in a sample selected to represent the AD pathologic continuum, and that education further modifies clinical expression. Thus, multiple concomitant etiologies of brain damage and premorbid characteristics contribute to the uncertainty of AD clinicopathologic correlations based only on tangles and plaques.

  1. Altered expression levels of the protein phosphatase 2A ABalphaC enzyme are associated with Alzheimer disease pathology.

    PubMed

    Sontag, Estelle; Luangpirom, Ampa; Hladik, Christa; Mudrak, Ingrid; Ogris, Egon; Speciale, Samuel; White, Charles L

    2004-04-01

    The formation of amyloid-containing senile plaques and tau-rich neurofibrillary tangles are central events in Alzheimer disease (AD) pathogenesis. Significantly, ABalphaC, a major protein phosphatase 2A (PP2A) holoenzyme, specifically binds to and dephosphorylates tau. Deregulation of PP2A results in tau hyperphosphorylation in vivo. Here, we compared the expression levels and distribution of PP2A subunits in various brain regions from autopsy cases of AD and aged controls with or without histological evidence of age-related neurofibrillary degeneration. Immunoblotting analyses revealed that there was a significant reduction in the total amounts of ABalphaC in AD frontal and temporal cortices that matched the decrease in PP2A activity measured in the same brain homogenates. Immunohistochemical studies showed that neuronal ABalphaC expression levels were significantly and selectively decreased in AD-affected regions and in tangle-bearing neurons, but not in AD cerebellum and in non-AD dementias. Reduced neuronal ABalphaC immunoreactivity closely correlated with tangle load, but not plaque burden, suggesting that ABalphaC dysfunction contributes to AD tau pathology. Glial cells within senile plaques were also positive for ABalphaC. Increased glial PP2A immunoreactivity was observed in both AD and non-AD cases and may play a role in the brain's response to general inflammatory processes and amyloidogenesis.

  2. Investigating Interventions in Alzheimer's Disease with Computer Simulation Models

    PubMed Central

    Proctor, Carole J.; Boche, Delphine; Gray, Douglas A.; Nicoll, James A. R.

    2013-01-01

    Progress in the development of therapeutic interventions to treat or slow the progression of Alzheimer's disease has been hampered by lack of efficacy and unforeseen side effects in human clinical trials. This setback highlights the need for new approaches for pre-clinical testing of possible interventions. Systems modelling is becoming increasingly recognised as a valuable tool for investigating molecular and cellular mechanisms involved in ageing and age-related diseases. However, there is still a lack of awareness of modelling approaches in many areas of biomedical research. We previously developed a stochastic computer model to examine some of the key pathways involved in the aggregation of amyloid-beta (Aβ) and the micro-tubular binding protein tau. Here we show how we extended this model to include the main processes involved in passive and active immunisation against Aβ and then demonstrate the effects of this intervention on soluble Aβ, plaques, phosphorylated tau and tangles. The model predicts that immunisation leads to clearance of plaques but only results in small reductions in levels of soluble Aβ, phosphorylated tau and tangles. The behaviour of this model is supported by neuropathological observations in Alzheimer patients immunised against Aβ. Since, soluble Aβ, phosphorylated tau and tangles more closely correlate with cognitive decline than plaques, our model suggests that immunotherapy against Aβ may not be effective unless it is performed very early in the disease process or combined with other therapies. PMID:24098635

  3. Business Planning Model Programmer’s Guide

    DTIC Science & Technology

    1993-12-01

    BPMREPI.PRG 847 temnpupgrade BPMOPEN.PRG 163 te - da -org BPMWHA2.PRG 1949 te tot BPMWHA2.PRG 1912 tgzzoggle BPMWHA2.PRG 349 tlbr UTILITY.PRG 921 toggle...closewindowIdispcapital get-totals disp capital. openwindow disp capital pad disp capital showeditinsg disp__capital tlbr disp capital wr-arr disp capital wr-dulsUdisp_...showeditnisg disp__contract tlbr disp contract wr -arrIdisp_ contract wr -duls disp contract wr uls disp__contract wrjyears disp expense closewindow

  4. Optomechanically induced spontaneous symmetry breaking

    NASA Astrophysics Data System (ADS)

    Miri, Mohammad-Ali; Verhagen, Ewold; Alú, Andrea

    2017-05-01

    We explore the dynamics of spontaneous breakdown of mirror symmetry in a pair of identical optomechanical cavities symmetrically coupled to a waveguide. Large optical intensities enable optomechanically induced nonlinear detuning of the optical resonators, resulting in a pitchfork bifurcation. We investigate the stability of this regime and explore the possibility of inducing multistability. By injecting proper trigger pulses, the proposed structure can toggle between two asymmetric stable states, thus serving as a low-noise nanophotonic all-optical switch or memory element.

  5. Variable-Reluctance Motor For Electric Vehicles

    NASA Technical Reports Server (NTRS)

    Lang, Jeffrey H.

    1987-01-01

    Report describes research on variable-reluctance electric-motor drive for eventual use in electric-vehicle propulsion. Primary design and performance criteria were torque and power output per unit mass of motor, cost, and drive efficiency. For each criterion, optimized drive design developed, and designs unified to yield single electric-vehicle drive. Scaled-down motor performed as expected. Prototype of paraplegic lift operated by toggle switch and joystick. Lift plugs into household electrical outlet for recharging when not in use.

  6. Fluid circulating pump operated by same incident solar energy which heats energy collection fluid

    NASA Technical Reports Server (NTRS)

    Collins, E. R.

    1980-01-01

    The application of using a spacecraft solar powered pump terrestrially to reduce or eliminate the need for fossil fuel generated electricity for domestic solar hot water systems was investigated. A breadboard prototype model was constructed utilizing bimetals to convert thermal energy into mechanical motion by means of a toggle operated shutter mechanism. Although it did not meet expected thermal efficiency, the prototype model was sufficient to demonstrate the mechanical concept.

  7. Glove box on vehicular instrument panel

    DOEpatents

    Atarashi, Kazuya

    1985-01-01

    A glove box for the upper surface of an automobile dashboard whereby it may be positioned close to the driver. The glove box lid is pivotally supported by arms extending down either side to swing forwardly for opening. A hook is pivotally support adjacent an arm and weighted to swing into engagement with the arm to prevent opening of the lid during abrupt deceleration. A toggle spring assists in maintaining the lid in either the open or closed position.

  8. A Multistate Toggle Switch Defines Fungal Cell Fates and Is Regulated by Synergistic Genetic Cues

    PubMed Central

    Anderson, Matthew Z.; Porman, Allison M.; Wang, Na; Mancera, Eugenio; Bennett, Richard J.

    2016-01-01

    Heritable epigenetic changes underlie the ability of cells to differentiate into distinct cell types. Here, we demonstrate that the fungal pathogen Candida tropicalis exhibits multipotency, undergoing stochastic and reversible switching between three cellular states. The three cell states exhibit unique cellular morphologies, growth rates, and global gene expression profiles. Genetic analysis identified six transcription factors that play key roles in regulating cell differentiation. In particular, we show that forced expression of Wor1 or Efg1 transcription factors can be used to manipulate transitions between all three cell states. A model for tristability is proposed in which Wor1 and Efg1 are self-activating but mutually antagonistic transcription factors, thereby forming a symmetrical self-activating toggle switch. We explicitly test this model and show that ectopic expression of WOR1 can induce white-to-hybrid-to-opaque switching, whereas ectopic expression of EFG1 drives switching in the opposite direction, from opaque-to-hybrid-to-white cell states. We also address the stability of induced cell states and demonstrate that stable differentiation events require ectopic gene expression in combination with chromatin-based cues. These studies therefore experimentally test a model of multistate stability and demonstrate that transcriptional circuits act synergistically with chromatin-based changes to drive cell state transitions. We also establish close mechanistic parallels between phenotypic switching in unicellular fungi and cell fate decisions during stem cell reprogramming. PMID:27711197

  9. Stochastic models for regulatory networks of the genetic toggle switch.

    PubMed

    Tian, Tianhai; Burrage, Kevin

    2006-05-30

    Bistability arises within a wide range of biological systems from the lambda phage switch in bacteria to cellular signal transduction pathways in mammalian cells. Changes in regulatory mechanisms may result in genetic switching in a bistable system. Recently, more and more experimental evidence in the form of bimodal population distributions indicates that noise plays a very important role in the switching of bistable systems. Although deterministic models have been used for studying the existence of bistability properties under various system conditions, these models cannot realize cell-to-cell fluctuations in genetic switching. However, there is a lag in the development of stochastic models for studying the impact of noise in bistable systems because of the lack of detailed knowledge of biochemical reactions, kinetic rates, and molecular numbers. In this work, we develop a previously undescribed general technique for developing quantitative stochastic models for large-scale genetic regulatory networks by introducing Poisson random variables into deterministic models described by ordinary differential equations. Two stochastic models have been proposed for the genetic toggle switch interfaced with either the SOS signaling pathway or a quorum-sensing signaling pathway, and we have successfully realized experimental results showing bimodal population distributions. Because the introduced stochastic models are based on widely used ordinary differential equation models, the success of this work suggests that this approach is a very promising one for studying noise in large-scale genetic regulatory networks.

  10. Stochastic models for regulatory networks of the genetic toggle switch

    PubMed Central

    Tian, Tianhai; Burrage, Kevin

    2006-01-01

    Bistability arises within a wide range of biological systems from the λ phage switch in bacteria to cellular signal transduction pathways in mammalian cells. Changes in regulatory mechanisms may result in genetic switching in a bistable system. Recently, more and more experimental evidence in the form of bimodal population distributions indicates that noise plays a very important role in the switching of bistable systems. Although deterministic models have been used for studying the existence of bistability properties under various system conditions, these models cannot realize cell-to-cell fluctuations in genetic switching. However, there is a lag in the development of stochastic models for studying the impact of noise in bistable systems because of the lack of detailed knowledge of biochemical reactions, kinetic rates, and molecular numbers. In this work, we develop a previously undescribed general technique for developing quantitative stochastic models for large-scale genetic regulatory networks by introducing Poisson random variables into deterministic models described by ordinary differential equations. Two stochastic models have been proposed for the genetic toggle switch interfaced with either the SOS signaling pathway or a quorum-sensing signaling pathway, and we have successfully realized experimental results showing bimodal population distributions. Because the introduced stochastic models are based on widely used ordinary differential equation models, the success of this work suggests that this approach is a very promising one for studying noise in large-scale genetic regulatory networks. PMID:16714385

  11. Conformational Toggling of Yeast Iso-1-Cytochrome c in the Oxidized and Reduced States

    PubMed Central

    Yang, Zhongzheng; Zhu, Jing; Ying, Tianlei; Jiang, Xianwang; Zhang, Xu; Wu, Houming; Liu, Maili; Tan, Xiangshi; Cao, Chunyang; Huang, Zhong-Xian

    2011-01-01

    To convert cyt c into a peroxidase-like metalloenzyme, the P71H mutant was designed to introduce a distal histidine. Unexpectedly, its peroxidase activity was found even lower than that of the native, and that the axial ligation of heme iron was changed to His71/His18 in the oxidized state, while to Met80/His18 in the reduced state, characterized by UV-visible, circular dichroism, and resonance Raman spectroscopy. To further probe the functional importance of Pro71 in oxidation state dependent conformational changes occurred in cyt c, the solution structures of P71H mutant in both oxidation states were determined. The structures indicate that the half molecule of cyt c (aa 50–102) presents a kind of “zigzag riveting ruler” structure, residues at certain positions of this region such as Pro71, Lys73 can move a big distance by altering the tertiary structure while maintaining the secondary structures. This finding provides a molecular insight into conformational toggling in different oxidation states of cyt c that is principle significance to its biological functions in electron transfer and apoptosis. Structural analysis also reveals that Pro71 functions as a key hydrophobic patch in the folding of the polypeptide of the region (aa 50–102), to prevent heme pocket from the solvent. PMID:22087268

  12. Advances in methods to characterize ligand-induced ionic lock and rotamer toggle molecular switch in G protein-coupled receptors.

    PubMed

    Xie, Xiang-Qun; Chowdhury, Ananda

    2013-01-01

    Structural biology of GPCRs has made significant progress upon recently developed technologies for GPCRs expression/purification and elucidation of GPCRs crystal structures. The crystal structures provide a snapshot of the receptor structural disposition of GPCRs itself or with cocrystallized ligands, and the results are congruent with biophysical and computer modeling studies reported about GPCRs conformational and dynamics flexibility, regulated activation, and the various stabilizing interactions, such as "molecular switches." The molecular switches generally constitute the most conserved domains within a particular GPCR superfamily. Often agonist-induced receptor activation proceeds by the disruption of majority of these interactions, while antagonist and inverse agonist act as blockers and structural stabilizers, respectively. Several elegant studies, particularly for the β2AR, have demonstrated the relationship between ligand structure, receptor conformational changes, and corresponding pharmacological outcomes. Thus, it is of great importance to understand GPCRs activation related to cell signaling pathways. Herein, we summarize the steps to produce functional GPCRs, generate suitably fluorescent labeled GPCRs and the procedure to use that to understand if ligand-induced activation can proceed by activation of the GPCRs via ionic lock switch and/or rotamer toggle switch mechanisms. Such understanding of ligand structure and mechanism of receptor activation will provide great insight toward uncovering newer pathways of GPCR activation and aid in structure-based drug design. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Extracellular neurofibrillary tangles associated with degenerating neurites and neuropil threads in Alzheimer-type dementia.

    PubMed

    Yamaguchi, H; Nakazato, Y; Kawarabayashi, T; Ishiguro, K; Ihara, Y; Morimatsu, M; Hirai, S

    1991-01-01

    We examined the cellular components of extracellular neurofibrillary tangles (E-NFT) in the hippocampal areas in cases with Alzheimer-type dementia. Immunohistochemically, the E-NFT were labeled for the C terminus of tau and glial fibrillary acidic protein. Moreover, the majority of the E-NFT was associated with intensely argyrophilic rods and with tau- and ubiquitin-immunoreactive dots. Ultrastructurally, the E-NFT consisted mainly of extracellular paired helical filaments (PHF) and astroglial processes. The extracellular PHF tended to be straighter and thinner. One third of the E-NFT was associated with small degenerating neurites containing many dense bodies and with neuropil threads containing PHF. These findings suggested that extracellular PHF promote both intense astroglial reaction and neuritic alteration, and that the E-NFT are continuously changing their morphology.

  14. Computational Study of Pseudo-phosphorylation of the Microtubule associated Protein Tau

    NASA Astrophysics Data System (ADS)

    Prokopovich, Dmitriy; Larini, Luca

    This computational study focuses on the effect of pseudo-phosphorylation on the aggregation of the microtubule associated protein tau. In the axon of the neuron, tau regulates the assembly of microtubules in the cytoskeleton. This is important for both stabilization of and transport across the microtubules. One of the hallmarks of the Alzheimer's disease is that tau is hyper-phosphorylated and aggregates into neurofibrillary tangles that lay waste to the neurons. It is not known if hyper-phosphorylation directly causes the aggregation of tau into tangles. Experimentally, pseudo-phosphorylation mimics the effects of phosphorylation by mutating certain residues of the protein chain into charged residues. In this study, we will consider the fragment called PHF43 that belongs to the microtubule binding region and has been shown to readily aggregate.

  15. Experimental verification of a new Bell-type inequality

    NASA Astrophysics Data System (ADS)

    Zhao, Jia-Qiang; Cao, Lian-Zhen; Yang, Yang; Li, Ying-De; Lu, Huai-Xin

    2018-05-01

    Arpan Das et al. proposed a set of new Bell inequalities (Das et al., 2017 [16]) for a three-qubit system and claimed that each inequality within this set is violated by all generalized Greenberger-Horne-Zeilinger (GGHZ) states. We investigate experimentally the new inequalities in the three-photon GGHZ class states. Since the inequalities are symmetric under the identical particles system, we chose one Bell-type inequality from the set arbitrarily. The experimental data well verified the theoretical prediction. Moreover, the experimental results show that the amount of violation of the new Bell inequality against locality realism increases monotonically following the increase of the tangle of the GGHZ state. The most profound physical essence revealed by the results is that the nonlocality of GGHZ state correlate with three tangles directly.

  16. Apolipoprotein E and Sex Bias in Cerebrovascular Aging of Men and Mice.

    PubMed

    Finch, Caleb E; Shams, Sara

    2016-09-01

    Alzheimer disease (AD) research has mainly focused on neurodegenerative processes associated with the classic neuropathologic markers of senile plaques and neurofibrillary tangles. Additionally, cerebrovascular contributions to dementia are increasingly recognized, particularly from cerebral small vessel disease (SVD). Remarkably, in AD brains, the apolipoprotein E (ApoE) ɛ4 allele shows male excess for cerebral microbleeds (CMBs), a marker of SVD, which is opposite to the female excess of plaques and tangles. Mouse transgenic models add further complexities to sex-ApoE ɛ4 allele interactions, with female excess of both CMBs and brain amyloid. We conclude that brain aging and AD pathogenesis cannot be understood in humans without addressing major gaps in the extent of sex differences in cerebrovascular pathology. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. γ-Aminobutyric Acid (GABA) Production and Angiotensin-I Converting Enzyme (ACE) Inhibitory Activity of Fermented Soybean Containing Sea Tangle by the Co-Culture of Lactobacillus brevis with Aspergillus oryzae.

    PubMed

    Jang, Eun Kyeong; Kim, Nam Yeun; Ahn, Hyung Jin; Ji, Geun Eog

    2015-08-01

    To enhance the γ-aminobutyric acid (GABA) content, the optimized fermentation of soybean with added sea tangle extract was evaluated at 30°C and pH 5.0. The medium was first inoculated with Aspergillus oryzae strain FMB S46471 and fermented for 3 days, followed by the subsequent inoculation with Lactobacillus brevis GABA 100. After fermentation for 7 days, the fermented soybean showed approximately 1.9 g/kg GABA and exhibited higher ACE inhibitory activity than the traditional soybean product. Furthermore, several peptides in the fraction containing the highest ACE inhibitory activity were identified. The novel fermented soybean enriched with GABA and ACE inhibitory components has great pharmaceutical and functional food values.

  18. Forecasting transitions in systems with high-dimensional stochastic complex dynamics: a linear stability analysis of the tangled nature model.

    PubMed

    Cairoli, Andrea; Piovani, Duccio; Jensen, Henrik Jeldtoft

    2014-12-31

    We propose a new procedure to monitor and forecast the onset of transitions in high-dimensional complex systems. We describe our procedure by an application to the tangled nature model of evolutionary ecology. The quasistable configurations of the full stochastic dynamics are taken as input for a stability analysis by means of the deterministic mean-field equations. Numerical analysis of the high-dimensional stability matrix allows us to identify unstable directions associated with eigenvalues with a positive real part. The overlap of the instantaneous configuration vector of the full stochastic system with the eigenvectors of the unstable directions of the deterministic mean-field approximation is found to be a good early warning of the transitions occurring intermittently.

  19. Pathological conformations involving the amino terminus of tau occur early in Alzheimer’s disease and are differentially detected by monoclonal antibodies

    PubMed Central

    Combs, Benjamin; Hamel, Chelsey; Kanaan, Nicholas M.

    2016-01-01

    Conformational changes involving the amino terminus of the tau protein are among the earliest alterations associated with tau pathology in Alzheimer’s disease and other tauopathies. This region of tau contains a phosphatase-activating domain (PAD) that is aberrantly exposed in pathological forms of the protein, an event that is associated with disruptions in anterograde fast axonal transport. We utilized four antibodies that recognize the amino terminus of tau, TNT1, TNT2 (a novel antibody), Tau12, and Tau13, to further study this important region. Using scanning alanine mutations in recombinant tau proteins, we refined the epitopes of each antibody. We examined the antibodies’ relative abilities to specifically label pathological tau in non-denaturing and denaturing assays to gain insight into some of the mechanistic details of PAD exposure. We then determined the pattern of tau pathology labeled by each antibody in human hippocampal sections at various disease stages in order to characterize PAD exposure in the context of disease progression. The characteristics of reactivity for the antibodies fell into two groups. TNT1 and TNT2 recognized epitopes within amino acids 7–12 and specifically identified recombinant tau aggregates and pathological tau from Alzheimer’s disease brains in a conformation-dependent manner. These antibodies labeled early pre-tangle pathology from neurons in early Braak stages and colocalized with thiazine red, a marker of fibrillar pathology, in classic neurofibrillary tangles. However, late tangles were negative for TNT1 and TNT2 indicating a loss of the epitope in later stages of tangle evolution. In contrast, Tau12 and Tau13 both identified discontinuous epitopes in the amino terminus and were unable to differentiate between normal and pathological tau in biochemical and tissue immunohistological assays. Despite the close proximity of these epitopes, the antibodies demonstrated remarkably different abilities to identify pathological changes in tau indicating that detection of conformational alterations involving PAD exposure is not achieved by all N-terminal tau antibodies and that a relatively discrete region of the N-terminus (i.e., amino acids 7–12, the TNT1 and TNT2 epitope) is central to the differences between normal and pathological tau. The appearance of PAD in early tau pathology and its disappearance in late-stage tangles suggest that toxic forms of tau are associated with the earliest forms of tau deposits. Collectively, these findings demonstrate that the TNT antibodies are useful markers for early conformational display of PAD and provide information regarding conformational changes that have potential implications in the toxic mechanisms of tau pathology. PMID:27260838

  20. Ethical Considerations of Community-based Participatory Research: Contextual Underpinnings for Developing Countries

    PubMed Central

    Jamshidi, Ensiyeh; Morasae, Esmaeil Khedmati; Shahandeh, Khandan; Majdzadeh, Reza; Seydali, Elham; Aramesh, Kiarash; Abknar, Nina Loori

    2014-01-01

    Background: The nature of community-based participatory research (CBPR) poses distinctive ethical challenges. In the absence of organized guidelines, a remarkable amount of researchers’ time and energy will be spent tackling these ethical challenges. The study aimed to explore ethical issues and principles potentially arising when conducting CBPR. Methods: This qualitative study conducted in CBPR Center of Tehran University of Medical Sciences. Required data were gathered through systematic literature review and semi-structured interviews. Representatives of community, academia, and nongovernmental organizations (NGOs) participated in our study. Ten interviews with representatives of partner organizations, four group interviews with academic staff, and four with representatives of community were conducted. Repeated thematic analysis was used to elicit ethics-related overarching themes from transcribed interviews. As recommendations, these themes were then organized into a set of CBPR-related ethical issues and principles. Results: Four CBPR ethical guidelines (including 173 articles) were selected from a systematic review. Overarching themes relating to ethical principles which emerged from interviews were as follows: Trust, transparency and accountability, equity and inclusion, power imbalance, tolerance and conflict management, and attention to cultural sensitivity. Practical principles that emerged included: Consensus rather than informed consent, ownership of data and research achievements, and sustainability and maintenance of relationships. According to findings and in comparison to international guidelines, the present study put more emphasis on cultural sensitivity and sustainability as CBPR ethical tangles. Conclusions: Community-based participatory research ethical challenges are of the same kind in most parts of the world. However, some discrepancies exist that calls for local scrutiny. Future use and critic of current explored ethical issues and principles are highly encouraged. PMID:25400893

  1. Camarada on middeck

    NASA Image and Video Library

    2005-08-04

    S114-E-7003 (4 August 2005) --- Astronaut Charles J. Camarda, STS-114 mission specialist, performs a middeck evaluation of the mechanical "plug" option for Reinforced Carbon-Carbon (RCC) repair aboard the Space Shuttle Discovery. Camarda used special pre-designated tools to accomplish the procedure, along with round thin, flexible 7-inch-diamter carbon-silicon cover plates designed to flex up to 0.25 inch to conform to the wing leading edge RCC panels, a hardware attachment mechanism similar to a toggle bolt and sealant.

  2. Let's Use Cognitive Science to Create Collaborative Workstations.

    PubMed

    Reicher, Murray A; Wolfe, Jeremy M

    2016-05-01

    When informed by an understanding of cognitive science, radiologists' workstations could become collaborative to improve radiologists' performance and job satisfaction. The authors review relevant literature and present several promising areas of research, including image toggling, eye tracking, cognitive computing, intelligently restricted messaging, work habit tracking, and innovative input devices. The authors call for more research in "perceptual design," a promising field that can complement advances in computer-aided detection. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  3. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Milkov, Mihail M.

    A comparator circuit suitable for use in a column-parallel single-slope analog-to-digital converter comprises a comparator, an input voltage sampling switch, a sampling capacitor arranged to store a voltage which varies with an input voltage when the sampling switch is closed, and a local ramp buffer arranged to buffer a global voltage ramp applied at an input. The comparator circuit is arranged such that its output toggles when the buffered global voltage ramp exceeds the stored voltage. Both DC- and AC-coupled comparator embodiments are disclosed.

  4. Genuine four tangle for four qubit states

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sharma, S. Shelly; Sharma, N. K.

    We report a four qubit polynomial invariant that quantifies genuine four-body correlations. The four qubit invariants are obtained from transformation properties of three qubit invariants under a local unitary on the fourth qubit.

  5. 2-Styrylindolium based fluorescent probes visualize neurofibrillary tangles in Alzheimer's disease.

    PubMed

    Gu, Jiamin; Anumala, Upendra Rao; Lo Monte, Fabio; Kramer, Thomas; Heyny von Haußen, Roland; Hölzer, Jana; Goetschy-Meyer, Valérie; Mall, Gerhard; Hilger, Ingrid; Czech, Christian; Schmidt, Boris

    2012-12-15

    We evaluated 2-styrylindolium derivatives (6-11) as novel and selective probes for neurofibrillary tangles (NFTs) on brain sections of AD patients. The staining experiments indicated that these compounds may bind selectively to NFTs in the presence of ß-amyloid (Aß) plaques. Cell free binding assays confirmed that 2-[2-[4-(1-pyrrolidinyl)phenyl]ethenyl]-1,3,3-trimethyl-3H-indolium iodide (9) and 2-[2-[4-(diethylamino)phenyl]ethenyl]-1-butyl-3,3-dimethyl-3H-indolium iodide (11) display excellent affinities to Tau-aggregates (IC(50) values of 5.1 and 1.4 nM, respectively) in the displacement of Thiazin Red R. These probes have good solubility in distilled water and low or no cytotoxicity in zebrafish embryo and liver hepatocellular carcinoma cell assays. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Nanoflare Heating of Solar and Stellar Coronae

    NASA Technical Reports Server (NTRS)

    Klimchuk, James A.

    2010-01-01

    A combination of observational and theoretical evidence suggests that much, and perhaps most, of the Sun's corona is heated by small unresolved bursts of energy called nanoflares. It seems likely that stellar coronae are heated in a similar fashion. Kanoflares are here taken to mean any impulsive heating that occurs within a magnetic flux strand. Many mechanisms have this property, including waves, but we prefer Parker's picture of tangled magnetic fields. The tangling is caused by turbulent convection at the stellar surface, and magnetic energy is released when the stresses reach a critical level. We suggest that the mechanism of energy release is the "secondary instability" of electric current sheets that are present at the boundaries between misaligned strands. I will discuss the collective evidence for solar and stellar nanoflares and hopefully present new results from the Solar Dynamics Observatory that was just launched.

  7. Camelid single-domain antibodies: A versatile tool for in vivo imaging of extracellular and intracellular brain targets.

    PubMed

    Li, Tengfei; Vandesquille, Matthias; Koukouli, Fani; Dudeffant, Clémence; Youssef, Ihsen; Lenormand, Pascal; Ganneau, Christelle; Maskos, Uwe; Czech, Christian; Grueninger, Fiona; Duyckaerts, Charles; Dhenain, Marc; Bay, Sylvie; Delatour, Benoît; Lafaye, Pierre

    2016-12-10

    Detection of intracerebral targets with imaging probes is challenging due to the non-permissive nature of blood-brain barrier (BBB). The present work describes two novel single-domain antibodies (VHHs or nanobodies) that specifically recognize extracellular amyloid deposits and intracellular tau neurofibrillary tangles, the two core lesions of Alzheimer's disease (AD). Following intravenous administration in transgenic mouse models of AD, in vivo real-time two-photon microscopy showed gradual extravasation of the VHHs across the BBB, diffusion in the parenchyma and labeling of amyloid deposits and neurofibrillary tangles. Our results demonstrate that VHHs can be used as specific BBB-permeable probes for both extracellular and intracellular brain targets and suggest new avenues for therapeutic and diagnostic applications in neurology. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Frequent coexistence of Lewy bodies and neurofibrillary tangles in the same neurons of patients with diffuse Lewy body disease.

    PubMed

    Iseki, E; Marui, W; Kosaka, K; Uéda, K

    1999-04-09

    We examined the frequency of neurons with coexistent Lewy bodies (LB) and neurofibrillary tangles (NFT) in diffuse Lewy body disease brains, by a double-immunostaining method using MDV2 and Human tau. Double-positive neurons were frequently observed in the limbic areas. These neurons mostly revealed the feature of intermingled MDV2- and Human tau-positive substances. Immunoelectron microscopically, the MDV2-positive components were not in continuity with the MDV2-negative paired helical filaments (PHF). The MDV2-positive LB were surrounded by the small PHF bundles, frequently accompanied by the randomly oriented PHF within LB. In the intermingled neurons, MDV2-positive non-filamentous components without LB were found among the large PHF bundles. These non-filamentous components may represent the early stage of LB formation.

  9. Improvements in Alzheimer's disease diagnosis using principle components analysis (PCA) in combination with Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Archer, John K. J.; Sudworth, Caroline D.; Williams, Rachel; How, Thien; Stone, Nicholas; Mann, David; Black, Richard A.

    2007-07-01

    The significant achievements of medical science over the last century are evident in the increasing age of the global population, however this now brings new problems, the most prominent being the growth in the number of people suffering from dementia. Over half the people with dementia in the UK are sufferers of Alzheimer's disease, a condition in which intraneuronal neurofibrillary tangles and extraneuronal senile tangles take over neurons prompting their death. A definitive diagnosis is still only currently available post-mortem, whilst current symptom based processes of elimination are far from perfect, especially when the only treatments available are symptom inhibiting drugs. Principal component analysis (PCA) of the Raman spectra taken from brain tissue has proved to be a potential tool in the diagnosis. However, this work now has to be refined in order to progress to tissue less associated with the symptoms of Alzheimer's disease. The first step of this has already been taken in progressing from frontal tissue to occipital tissue point spectra taken at random positions from bulk tissue. Now we present initial work into acquiring Raman spectral maps from across a tissue area, in pursuit of identifying unique plaque and tangle spectra. These spectra are presented alongside synthetic β-Amyloid spectra, in a study of the role that the peptide plays in the biomarker spectra, and how this information can aid the PCA of bulk tissue, and point towards a Raman spectroscopic test on less sensitive tissue, such as blood.

  10. The Effects of Verbal Instruction and Shaping to Improve Tackling by High School Football Players

    ERIC Educational Resources Information Center

    Harrison, Antonio M.; Pyles, David A.

    2013-01-01

    We evaluated verbal instruction and shaping using TAG (teaching with acoustical guidance) to improve tackling by 3 high school football players. Verbal instruction and shaping improved tackling for all 3 participants. In addition, performance was maintained as participants moved more quickly through the tackling procedure.

  11. Technical determinants of tackle and ruck performance in International rugby union.

    PubMed

    Hendricks, Sharief; van Niekerk, Tiffany; Sin, Drew Wade; Lambert, Mike; den Hollander, Steve; Brown, James; Maree, Willie; Treu, Paul; Till, Kevin; Jones, Ben

    2018-03-01

    The most frequently occurring contact events in rugby union are the tackle and ruck. The ability repeatedly to engage and win the tackle and ruck has been associated with team success. To win the tackle and ruck, players have to perform specific techniques. These techniques have not been studied at the highest level of rugby union. Therefore, the purpose of this study was to identify technical determinants of tackle and ruck performance at the highest level of rugby union. A total of 4479 tackle and 2914 ruck events were coded for the Six Nations and Championship competitions. Relative risk ratio (RR), the ratio of the probability of an outcome occurring when a characteristic was observed (versus the non-observed characteristic), was determined using multinomial logistic regression. Executing front-on tackles reduced the likelihood of offloads and tackle breaks in both competitions (Six Nations RR 3.0 Behind tackle, 95% confidence interval [95% CI]: 1.9-4.6, effect size [ES] = large, P < 0.001); Championship RR 2.9 Jersey tackle, 95% CI: 1.3-6.4, ES = moderate, P = 0.01). Fending during contact increased the chances of offloading and breaking the tackle in both competitions (Six Nations RR 4.5 Strong, 95% CI: 2.2-9.2, ES = large, P = P < 0.001; Championship RR 5.1 Moderate, 95% CI: 3.5-7.4, ES = large, P < 0.001). For the ruck, actively placing the ball increased the probability of maintaining possession (Six Nations RR 2.2, 95% CI: 1.1-4.3, ES = moderate, P = 0.03); Championship RR 4.0, 95% CI: 1.3-11.8, ES = large, P = 0.01). The techniques identified in this study should be incorporated and emphasised during training to prepare players for competition. Furthermore, these techniques need to be added to coaching manuals for the tackle and ruck.

  12. Tackle technique and tackle-related injuries in high-level South African Rugby Union under-18 players: real-match video analysis.

    PubMed

    Burger, Nicholas; Lambert, Michael I; Viljoen, Wayne; Brown, James C; Readhead, Clint; Hendricks, Sharief

    2016-08-01

    The high injury rate associated with rugby union is primarily due to the tackle, and poor contact technique has been identified as a risk factor for injury. We aimed to determine whether the tackle technique proficiency scores were different in injurious tackles versus tackles that did not result in injury using real-match scenarios in high-level youth rugby union. Injury surveillance was conducted at the under-18 Craven Week tournaments (2011-2013). Tackle-related injury information was used to identify injury events in the match video footage and non-injury events were identified for the injured player cohort. Injury and non-injury events were scored for technique proficiency and Cohen's effect sizes were calculated and the Student t test (p<0.05) was performed to compare injury versus non-injury scores. The overall mean score for front-on ball-carrier proficiency was 7.17±1.90 and 9.02±2.15 for injury and non-injury tackle events, respectively (effect size=moderate; p<0.05). The overall mean score for side/behind ball-carrier proficiency was 4.09±2.12 and 7.68±1.72 for injury and non-injury tackle events, respectively (effect size=large; p<0.01). The overall mean score for front-on tackler proficiency was 7.00±1.95 and 9.35±2.56 for injury and non-injury tackle events, respectively (effect size=moderate; p<0.05). The overall mean score for side/behind tackler proficiency was 5.47±1.60 and 8.14±1.75 for injury and non-injury tackle events, respectively (effect size=large; p<0.01). Higher overall mean and criterion-specific tackle-related technique scores were associated with a non-injury outcome. The ability to perform well during tackle events may decrease the risk of injury and may manifest in superior performance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  13. 46 CFR 121.300 - Ground tackle and mooring lines.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Ground tackle and mooring lines. 121.300 Section 121.300... MISCELLANEOUS SYSTEMS AND EQUIPMENT Mooring and Towing Equipment § 121.300 Ground tackle and mooring lines. A vessel must be fitted with ground tackle and mooring lines necessary for the vessel to be safely anchored...

  14. 46 CFR 121.300 - Ground tackle and mooring lines.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Ground tackle and mooring lines. 121.300 Section 121.300... MISCELLANEOUS SYSTEMS AND EQUIPMENT Mooring and Towing Equipment § 121.300 Ground tackle and mooring lines. A vessel must be fitted with ground tackle and mooring lines necessary for the vessel to be safely anchored...

  15. Nonlatching positive feedback enables robust bimodality by decoupling expression noise from the mean

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Razooky, Brandon S.; Cao, Youfang; Hansen, Maike M. K.

    Fundamental to biological decision-making is the ability to generate bimodal expression patterns where two alternate expression states simultaneously exist. Here in this study, we use a combination of single-cell analysis and mathematical modeling to examine the sources of bimodality in the transcriptional program controlling HIV’s fate decision between active replication and viral latency. We find that the HIV Tat protein manipulates the intrinsic toggling of HIV’s promoter, the LTR, to generate bimodal ON-OFF expression, and that transcriptional positive feedback from Tat shifts and expands the regime of LTR bimodality. This result holds for both minimal synthetic viral circuits and full-lengthmore » virus. Strikingly, computational analysis indicates that the Tat circuit’s non-cooperative ‘non-latching’ feedback architecture is optimized to slow the promoter’s toggling and generate bimodality by stochastic extinction of Tat. In contrast to the standard Poisson model, theory and experiment show that non-latching positive feedback substantially dampens the inverse noise-mean relationship to maintain stochastic bimodality despite increasing mean-expression levels. Given the rapid evolution of HIV, the presence of a circuit optimized to robustly generate bimodal expression appears consistent with the hypothesis that HIV’s decision between active replication and latency provides a viral fitness advantage. More broadly, the results suggest that positive-feedback circuits may have evolved not only for signal amplification but also for robustly generating bimodality by decoupling expression fluctuations (noise) from mean expression levels.« less

  16. NTM stabilization by alternating O-point EC current drive using a high-power diplexer

    NASA Astrophysics Data System (ADS)

    Kasparek, W.; Doelman, N.; Stober, J.; Maraschek, M.; Zohm, H.; Monaco, F.; Eixenberger, H.; Klop, W.; Wagner, D.; Schubert, M.; Schütz, H.; Grünwald, G.; Plaum, B.; Munk, R.; Schlüter, K. H.; ASDEX Upgrade Team

    2016-12-01

    At the tokamak ASDEX Upgrade, experiments to stabilize neoclassical tearing modes (NTMs) by electron cyclotron (EC) heating and current drive in the O-points of the magnetic islands were performed. For the first time, injection into the O-points of the revolving islands was performed via a fast directional switch, which toggled the EC power between two launchers synchronously to the island rotation. The switching was performed by a resonant diplexer employing a sharp resonance in the transfer function, and a small frequency modulation of the feeding gyrotron around the slope of the resonance. Thus, toggling of the power between the two outputs of the diplexer connected to two articulating launchers was possible. Phasing and control of the modulation were performed via a set of Mirnov coils and appropriate signal processing. In the paper, technological issues, the design of the diplexer, the tracking of the diplexer resonance to the gyrotron frequency, the generation and processing of control signals for the gyrotron, and the typical performance concerning switching contrast and efficiency are discussed. The plasma scenario is described, and plasma experiments are presented, where the launchers scanned the region of the resonant surface continuously and also where the launchers were at a fixed position near to the q  =  1.5-surface. In the second case, complete stabilization of a 3/2 NTM could be reached. These experiments are also seen as a technical demonstration for the applicability of diplexers in large-scale ECRH systems.

  17. Comparison of design and torque measurements of various manual wrenches.

    PubMed

    Neugebauer, Jörg; Petermöller, Simone; Scheer, Martin; Happe, Arndt; Faber, Franz-Josef; Zoeller, Joachim E

    2015-01-01

    Accurate torque application and determination of the applied torque during surgical and prosthetic treatment is important to reduce complications. A study was performed to determine and compare the accuracy of manual wrenches, which are available in different designs with a large range of preset torques. Thirteen different wrench systems with a variety of preset torques ranging from 10 to 75 Ncm were evaluated. Three different designs were available, with a spring-in-coil or toggle design as an active mechanism or a beam as a passive mechanism, to select the preset torque. To provide a clinically relevant analysis, a total of 1,170 torque measurements in the range of 10 to 45 Ncm were made in vitro using an electronic torque measurement device. The absolute deviations in Ncm and percent deviations across all wrenches were small, with a mean of -0.24 ± 2.15 Ncm and -0.84% ± 11.72% as a shortfall relative to the preset value. The greatest overage was 8.2 Ncm (82.5%), and the greatest shortfall was 8.47 Ncm (46%). However, extreme values were rare, with 95th-percentile values of -1.5% (lower value) and -0.16% (upper value). A comparison with respect to wrench design revealed significantly higher deviations for coil and toggle-style wrenches than for beam wrenches. Beam wrenches were associated with a lower risk of rare extreme values thanks to their passive mechanism of achieving the selected preset torque, which minimizes the risk of harming screw connections.

  18. An investigation of shoulder forces in active shoulder tackles in rugby union football.

    PubMed

    Usman, Juliana; McIntosh, Andrew S; Fréchède, Bertrand

    2011-11-01

    In rugby union football the tackle is the most frequently executed skill and one most associated with injury, including shoulder injury to the tackler. Despite the importance of the tackle, little is known about the magnitude of shoulder forces in the tackle and influencing factors. The objectives of the study were to measure the shoulder force in the tackle, as well as the effects of shoulder padding, skill level, side of body, player size, and experimental setting on shoulder force. Experiments were conducted in laboratory and field settings using a repeated measures design. Thirty-five participants were recruited to the laboratory and 98 to the field setting. All were male aged over 18 years with rugby experience. The maximum force applied to the shoulder in an active shoulder tackle was measured with a custom built forceplate incorporated into a 45 kg tackle bag. The overall average maximum shoulder force was 1660 N in the laboratory and 1997 N in the field. This difference was significant. The shoulder force for tackling without shoulder pads was 1684 N compared to 1635 N with shoulder pads. There was no difference between the shoulder forces on the dominant and non-dominant sides. Shoulder force reduced with tackle repetition. No relationship was observed between player skill level and size. A substantial force can be applied to the shoulder and to an opponent in the tackle. This force is within the shoulder's injury tolerance range and is unaffected by shoulder pads. Copyright © 2011 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  19. Catastrophic rugby injuries of the spinal cord: changing patterns of injury.

    PubMed Central

    Scher, A T

    1991-01-01

    In reports from the UK and New Zealand, it is noted that the incidence of rugby injuries to the cervical spinal cord has dropped and that the percentage of players injured in the tackle has similarly decreased. In contrast, this does not appear to be the pattern in South Africa and an analysis has therefore been made of 40 rugby players sustaining injuries to the spinal cord during the period 1985 to 1989. The radiological appearances on admission have been correlated with the circumstances of injury, associated orthopaedic injuries and neurological deficits. The tackle was responsible for the majority of injuries, causing more than the scrum. Tackles were also responsible for more cases of complete, permanent quadriplegia than the scrum. The commonest cause of injury in players being tackled was the high tackle around the neck, while the commonest cause of injury in players making the tackle was the dive tackle. This survey has shown that the tackle is now the major cause of spinal cord injury in South African rugby, in contrast to earlier analyses in which the scrum was identified as the most common cause. Images Figure 1 Figure 2 PMID:1913034

  20. Principal facts for 408 gravity stations in the vicinity of the Talkeetna Mountains, south-central Alaska

    USGS Publications Warehouse

    Morin, Robert L.; Glen, Jonathan M.G.

    2003-01-01

    Gravity data were collected between 1999 and 2002 along transects in the Talkeetna Mountains of south-central Alaska as part of a geological and geophysical study of the framework geology of the region. The study area lies between 61° 30’ and 63° 45’ N. latitude and 145° and 151° W. longitude. This data set includes 408 gravity stations. These data, combined with the pre-existing 3,286 stations, brings the total data in this area to 3,694 gravity stations. Principal facts for the 408 new gravity stations and the 15 gravity base stations used for control are listed in this report. During the summer of 1999, a gravity survey was conducted in the western Talkeetna Mountains. Measurements at 55 gravity stations were made. One gravity base station was used for control for this survey. This base station, STEP, is located at the Stephan Lake Lodge on Stephan Lake. The observed gravity of this station was calculated based on an indirect tie to base station ANCL in Anchorage. The temporary base used to tie between STEP and ANCL was REGL in Anchorage. During the summer of 2000, a gravity survey was conducted in the western Talkeetna Mountains. Measurements at 56 gravity stations were made. One gravity base station was used for control for this survey. This base station, GRHS, is located at the Gracious House Lodge on the Denali Highway. The observed gravity of this station was calculated based on multiple ties to base stations D87, and D57 along the Denali Highway. During the summer of 2001, a gravity survey was conducted in the western Talkeetna Mountains. Measurements at 90 gravity stations were made. One gravity base station was used for control for this survey. This base station, HLML, is located at the High Lake Lodge. The observed gravity of this station was calculated based on multiple ties to base stations ANCU in Anchorage, PALH in Palmer, WASA in Wasilla, and TLKM in Talkeetna. Also during the summer of 2001, a gravity survey was conducted in the vicinity of Tangle Lakes. Measurements at 86 gravity stations were made. The Tangle Lakes area is located about 25 km west of Paxson and north of the Denali Highway. One gravity base station was used for control for this survey. This base station, TLIN, is located at the Tangle Lakes Inn. The observed gravity of this station was calculated based on multiple ties to base stations ANCU in Anchorage, PALH in Palmer, BD27 in Gulkana, B-07 on the Richardson Highway, and base stations D42, and D57 along the Denali Highway. During the summer of 2002, measurements at an additional 107 gravity stations were made in the vicinity of Tangle Lakes. Base station TLIN at the Tangle Lakes Inn was again used for control. Additional ties to base stations ANCU and B-07 were made.

  1. Class, Gender, and Mobility: Unraveling the "Tangled Things."

    ERIC Educational Resources Information Center

    Cookson, Peter W., Jr.

    1990-01-01

    Reviews Sara Delamont's "Knowledgeable Women: Structuralism and the Reproduction of Elites" (1989), a feminist examination of the education of elite women which provides many insights into how gender and class operate within the dominant classes. (DM)

  2. Mechanisms of Protein Seeding in Neurodegenerative Diseases

    PubMed Central

    Walker, Lary C.; Diamond, Marc I.; Duff, Karen E.; Hyman, Bradley T.

    2013-01-01

    Most age-associated neurodegenerative diseases involve the aggregation of specific proteins within the nervous system. In Alzheimer’s disease, the insidious pathogenic process begins many years before the symptoms emerge, and the lesions that characterize the disease – senile plaques and neurofibrillary tangles – ramify systematically through the brain. We review evidence that the β-amyloid and tau proteins, which aggregate to form senile plaques and neurofibrillary tangles, respectively, are induced to misfold and self-assemble by a process of templated conformational change that amplifies a toxic species. Recent data also indicate that the spread of these lesions from one site to another is mediated by the cellular uptake, transport and release of endogenous seeds formed by the cognate proteins. This simple pathogenic principle suggests that the formation, trafficking and metabolism of pathogenic protein seeds are promising therapeutic targets for Alzheimer’s disease and other neurodegenerative disorders. PMID:23599928

  3. Hydrodynamical model of anisotropic, polarized turbulent superfluids. I: constraints for the fluxes

    NASA Astrophysics Data System (ADS)

    Mongiovì, Maria Stella; Restuccia, Liliana

    2018-02-01

    This work is the first of a series of papers devoted to the study of the influence of the anisotropy and polarization of the tangle of quantized vortex lines in superfluid turbulence. A thermodynamical model of inhomogeneous superfluid turbulence previously formulated is here extended, to take into consideration also these effects. The model chooses as thermodynamic state vector the density, the velocity, the energy density, the heat flux, and a complete vorticity tensor field, including its symmetric traceless part and its antisymmetric part. The relations which constrain the constitutive quantities are deduced from the second principle of thermodynamics using the Liu procedure. The results show that the presence of anisotropy and polarization in the vortex tangle affects in a substantial way the dynamics of the heat flux, and allow us to give a physical interpretation of the vorticity tensor here introduced, and to better describe the internal structure of a turbulent superfluid.

  4. Quantum teleportation and Birman-Murakami-Wenzl algebra

    NASA Astrophysics Data System (ADS)

    Zhang, Kun; Zhang, Yong

    2017-02-01

    In this paper, we investigate the relationship of quantum teleportation in quantum information science and the Birman-Murakami-Wenzl (BMW) algebra in low-dimensional topology. For simplicity, we focus on the two spin-1/2 representation of the BMW algebra, which is generated by both the Temperley-Lieb projector and the Yang-Baxter gate. We describe quantum teleportation using the Temperley-Lieb projector and the Yang-Baxter gate, respectively, and study teleportation-based quantum computation using the Yang-Baxter gate. On the other hand, we exploit the extended Temperley-Lieb diagrammatical approach to clearly show that the tangle relations of the BMW algebra have a natural interpretation of quantum teleportation. Inspired by this interpretation, we construct a general representation of the tangle relations of the BMW algebra and obtain interesting representations of the BMW algebra. Therefore, our research sheds a light on a link between quantum information science and low-dimensional topology.

  5. A New Probe of Line-of-sight Magnetic Field Tangling

    NASA Astrophysics Data System (ADS)

    Clark, S. E.

    2018-04-01

    The Galactic neutral hydrogen (H I ) sky at high Galactic latitudes is suffused with linear structure. Particularly prominent in narrow spectral intervals, these linear H I features are well aligned with the plane-of-sky magnetic field orientation as measured with optical starlight polarization and polarized thermal dust emission. We analyze the coherence of the orientation of these features with respect to line-of-sight velocity, and propose a new metric to quantify this H I coherence. We show that H I coherence is linearly correlated with the polarization fraction of 353 GHz dust emission. H I coherence constitutes a novel method for measuring the degree of magnetic field tangling along the line of sight in the diffuse interstellar medium. We propose applications of this property for H I -based models of the polarized dust emission in diffuse regions, and for studies of frequency decorrelation in the polarized dust foreground to the cosmic microwave background (CMB).

  6. Anisotropic Formation of Quantum Turbulence Generated by a Vibrating Wire in Superfluid {}4{He}

    NASA Astrophysics Data System (ADS)

    Yano, H.; Ogawa, K.; Chiba, Y.; Obara, K.; Ishikawa, O.

    2017-06-01

    To investigate the formation of quantum turbulence in superfluid {}4{He}, we have studied the emission of vortex rings with a ring size of larger than 38 μm in diameter from turbulence generated by a vibrating wire. The emission rate of vortex rings from a turbulent region remains low until the beginning of high-rate emissions, suggesting that some of the vortex lines produced by the wire combine to form a vortex tangle, until an equilibrium is established between the rate of vortex line combination with the tangle and dissociation. The formation times of equilibrium turbulence are proportional to ɛ ^{-1.2} and ɛ ^{-0.6} in the directions perpendicular and parallel to the vibrating direction of the generator, respectively, indicating the anisotropic formation of turbulence. Here, ɛ is the generation power of the turbulence. This power dependence may be associated with the characteristics of quantum turbulence with a constant energy flux.

  7. Tau Pathology Induces Excitatory Neuron Loss, Grid Cell Dysfunction and Spatial Memory Deficits Reminiscent of Early Alzheimer's Disease

    PubMed Central

    Fu, Hongjun; Rodriguez, Gustavo A.; Herman, Mathieu; Emrani, Sheina; Nahmani, Eden; Barrett, Geoffrey; Figueroa, Helen Y.; Goldberg, Eliana

    2017-01-01

    Summary The earliest stages of Alzheimer's disease (AD) are characterized by the formation of mature tangles in the entorhinal cortex and disorientation and confusion navigating familiar places. The medial entorhinal cortex (MEC) contains specialized neurons called grid cells that form part of the spatial navigation system. Here we show in a transgenic mouse model expressing mutant human tau predominantly in the EC that the formation of mature tangles in old mice was associated with excitatory cell loss and deficits in grid cell function, including destabilized grid fields and reduced firing rates, as well as altered network activity. Overt tau pathology in the aged mice was accompanied by spatial memory deficits. Therefore, tau pathology initiated in the entorhinal cortex could lead to deficits in grid cell firing and underlie the deterioration of spatial cognition seen in human AD. PMID:28111080

  8. Brachistochrone of entanglement for spin chains

    NASA Astrophysics Data System (ADS)

    Carlini, Alberto; Koike, Tatsuhiko

    2017-03-01

    We analytically investigate the role of entanglement in time-optimal state evolution as an application of the quantum brachistochrone, a general method for obtaining the optimal time-dependent Hamiltonian for reaching a target quantum state. As a model, we treat two qubits indirectly coupled through an intermediate qubit that is directly controllable, which represents a typical situation in quantum information processing. We find the time-optimal unitary evolution law and quantify residual entanglement by the two-tangle between the indirectly coupled qubits, for all possible sets of initial pure quantum states of a tripartite system. The integrals of the motion of the brachistochrone are determined by fixing the minimal time at which the residual entanglement is maximized. Entanglement plays a role for W and Greenberger-Horne-Zeilinger (GHz) initial quantum states, and for the bi-separable initial state in which the indirectly coupled qubits have a nonzero value of the 2-tangle.

  9. Tripartite entanglement versus tripartite nonlocality in three-qubit Greenberger-Horne-Zeilinger-class states.

    PubMed

    Ghose, S; Sinclair, N; Debnath, S; Rungta, P; Stock, R

    2009-06-26

    We analyze the relationship between tripartite entanglement and genuine tripartite nonlocality for three-qubit pure states in the Greenberger-Horne-Zeilinger class. We consider a family of states known as the generalized Greenberger-Horne-Zeilinger states and derive an analytical expression relating the three-tangle, which quantifies tripartite entanglement, to the Svetlichny inequality, which is a Bell-type inequality that is violated only when all three qubits are nonlocally correlated. We show that states with three-tangle less than 1/2 do not violate the Svetlichny inequality. On the other hand, a set of states known as the maximal slice states does violate the Svetlichny inequality, and exactly analogous to the two-qubit case, the amount of violation is directly related to the degree of tripartite entanglement. We discuss further interesting properties of the generalized Greenberger-Horne-Zeilinger and maximal slice states.

  10. Momentum and Kinetic Energy Before the Tackle in Rugby Union

    PubMed Central

    Hendricks, Sharief; Karpul, David; Lambert, Mike

    2014-01-01

    Understanding the physical demands of a tackle in match situations is important for safe and effective training, developing equipment and research. Physical components such as momentum and kinetic energy, and it relationship to tackle outcome is not known. The aim of this study was to compare momenta between ball-carrier and tackler, level of play (elite, university and junior) and position (forwards vs. backs), and describe the relationship between ball-carrier and tackler mass, velocity and momentum and the tackle outcome. Also, report on the ball-carrier and tackler kinetic energy before contact and the estimated magnitude of impact (energy distributed between ball-carrier and tackler upon contact). Velocity over 0.5 seconds before contact was determined using a 2-dimensional scaled version of the field generated from a computer alogorithm. Body masses of players were obtained from their player profiles. Momentum and kinetic energy were subsequently calculated for 60 tackle events. Ball-carriers were heavier than the tacklers (ball-carrier 100 ± 14 kg vs. tackler 93 ± 11 kg, d = 0.52, p = 0.0041, n = 60). Ball-carriers as forwards had a significantly higher momentum than backs (forwards 563 ± 226 Kg.m.s-1 n = 31 vs. backs 438 ± 135 Kg.m.s-1, d = 0.63, p = 0.0012, n = 29). Tacklers dominated 57% of tackles and ball-carriers dominated 43% of tackles. Despite the ball-carrier having a mass advantage before contact more frequently than the tackler, momentum advantage and tackle dominance between the ball-carrier and tackler was proportionally similar. These findings may reflect a characteristic of the modern game of rugby where efficiently heavier players (particularly forwards) are tactically predetermined to carry the ball in contact. Key Points First study to quantify momentum, kinetic energy, and magnitude of impact in rugby tackles across different levels in matches without a device attached to a player. Physical components alone, of either ball-carrier or tackler, are not good predictors of tackle dominance. The range of magnitudes of impact of injury free tackles observed in this study provides evidence for the physical tolerance of players during the tackle. PMID:25177182

  11. Momentum and kinetic energy before the tackle in rugby union.

    PubMed

    Hendricks, Sharief; Karpul, David; Lambert, Mike

    2014-09-01

    Understanding the physical demands of a tackle in match situations is important for safe and effective training, developing equipment and research. Physical components such as momentum and kinetic energy, and it relationship to tackle outcome is not known. The aim of this study was to compare momenta between ball-carrier and tackler, level of play (elite, university and junior) and position (forwards vs. backs), and describe the relationship between ball-carrier and tackler mass, velocity and momentum and the tackle outcome. Also, report on the ball-carrier and tackler kinetic energy before contact and the estimated magnitude of impact (energy distributed between ball-carrier and tackler upon contact). Velocity over 0.5 seconds before contact was determined using a 2-dimensional scaled version of the field generated from a computer alogorithm. Body masses of players were obtained from their player profiles. Momentum and kinetic energy were subsequently calculated for 60 tackle events. Ball-carriers were heavier than the tacklers (ball-carrier 100 ± 14 kg vs. tackler 93 ± 11 kg, d = 0.52, p = 0.0041, n = 60). Ball-carriers as forwards had a significantly higher momentum than backs (forwards 563 ± 226 Kg(.)m(.)s(-1) n = 31 vs. backs 438 ± 135 Kg(.)m(.)s(-1), d = 0.63, p = 0.0012, n = 29). Tacklers dominated 57% of tackles and ball-carriers dominated 43% of tackles. Despite the ball-carrier having a mass advantage before contact more frequently than the tackler, momentum advantage and tackle dominance between the ball-carrier and tackler was proportionally similar. These findings may reflect a characteristic of the modern game of rugby where efficiently heavier players (particularly forwards) are tactically predetermined to carry the ball in contact. Key PointsFirst study to quantify momentum, kinetic energy, and magnitude of impact in rugby tackles across different levels in matches without a device attached to a player.Physical components alone, of either ball-carrier or tackler, are not good predictors of tackle dominance.The range of magnitudes of impact of injury free tackles observed in this study provides evidence for the physical tolerance of players during the tackle.

  12. Does player time-in-game affect tackle technique in elite level rugby union?

    PubMed

    Tierney, Gregory J; Denvir, Karl; Farrell, Garreth; Simms, Ciaran K

    2018-02-01

    It has been hypothesised that fatigue may be a major factor in tackle-related injury risk in rugby union and hence more injuries occur in the later stages of a game. The aim of this study is to identify changes in ball carrier or tackler proficiency characteristics, using elite level match video data, as player time-in-game increases. Qualitative observational cohort study. Three 2014/15 European Rugby Champions Cup games were selected for ball carrier and tackler proficiency analysis. Analysis was only conducted on players who started and remained on the field for the entire game. A separate analysis was conducted on 10 randomly selected 2014/15 European Rugby Champions Cup/Pro 12 games to assess the time distribution of tackles throughout a game. A Chi-square test and one-way way ANOVA with post-hoc testing was conducted to identify significant differences (p<0.05) for proficiency characteristics and tackle counts between quarters in the game, respectively. Player time-in-game did not affect tackle proficiency for both the ball carrier and tackler. Any results that showed statistical significance did not indicate a trend of deterioration in proficiency with increased player time-in-game. The time distribution of tackles analysis indicated that more tackles occurring in the final quarter of the game than the first (p=0.04) and second (p=<0.01). It appears that player time-in-game does not affect tackler or ball carrier tackle technique proficiency at the elite level. More tackles occurring in the final quarter of a game provides an alternative explanation to more tackle-related injuries occurring at this stage. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  13. High-order computer-assisted estimates of topological entropy

    NASA Astrophysics Data System (ADS)

    Grote, Johannes

    The concept of Taylor Models is introduced, which offers highly accurate C0-estimates for the enclosures of functional dependencies, combining high-order Taylor polynomial approximation of functions and rigorous estimates of the truncation error, performed using verified interval arithmetic. The focus of this work is on the application of Taylor Models in algorithms for strongly nonlinear dynamical systems. A method to obtain sharp rigorous enclosures of Poincare maps for certain types of flows and surfaces is developed and numerical examples are presented. Differential algebraic techniques allow the efficient and accurate computation of polynomial approximations for invariant curves of certain planar maps around hyperbolic fixed points. Subsequently we introduce a procedure to extend these polynomial curves to verified Taylor Model enclosures of local invariant manifolds with C0-errors of size 10-10--10 -14, and proceed to generate the global invariant manifold tangle up to comparable accuracy through iteration in Taylor Model arithmetic. Knowledge of the global manifold structure up to finite iterations of the local manifold pieces enables us to find all homoclinic and heteroclinic intersections in the generated manifold tangle. Combined with the mapping properties of the homoclinic points and their ordering we are able to construct a subshift of finite type as a topological factor of the original planar system to obtain rigorous lower bounds for its topological entropy. This construction is fully automatic and yields homoclinic tangles with several hundred homoclinic points. As an example rigorous lower bounds for the topological entropy of the Henon map are computed, which to the best knowledge of the authors yield the largest such estimates published so far.

  14. Primary age-related tauopathy (PART): a common pathology associated with human aging

    PubMed Central

    Crary, John F.; Trojanowski, John Q.; Schneider, Julie A.; Abisambra, Jose F.; Abner, Erin L.; Alafuzoff, Irina; Arnold, Steven E.; Attems, Johannes; Beach, Thomas G.; Bigio, Eileen H.; Cairns, Nigel J.; Dickson, Dennis W.; Gearing, Marla; Grinberg, Lea T.; Hof, Patrick R.; Hyman, Bradley T.; Jellinger, Kurt; Jicha, Gregory A.; Kovacs, Gabor G.; Knopman, David S.; Kofler, Julia; Kukull, Walter A.; Mackenzie, Ian R.; Masliah, Eliezer; McKee, Ann; Montine, Thomas J.; Murray, Melissa E.; Neltner, Janna H.; Santa-Maria, Ismael; Seeley, William W.; Serrano-Pozo, Alberto; Shelanski, Michael L.; Stein, Thor; Takao, Masaki; Thal, Dietmar R.; Toledo, Jonathan B.; Troncoso, Juan C.; Vonsattel, Jean Paul; White, Charles L.; Wisniewski, Thomas; Woltjer, Randall L.; Yamada, Masahito; Nelson, Peter T.

    2014-01-01

    We recommend a new term, “primary age-related tauopathy” (PART), to describe a pathology that is commonly observed in the brains of aged individuals. Many autopsy studies have reported brains with neurofibrillary tangles (NFT) that are indistinguishable from those of Alzheimer's disease (AD), in the absence of amyloid (Aβ) plaques. For these “NFT+/Aβ−” brains, for which formal criteria for AD neuropathologic changes are not met, the NFT are mostly restricted to structures in the medial temporal lobe, basal forebrain, brainstem, and olfactory areas (bulb and cortex). Symptoms in persons with PART usually range from normal to amnestic cognitive changes, with only a minority exhibiting profound impairment. Because cognitive impairment is often mild, existing clinicopathologic designations, such as “tangle-only dementia” and “tangle-predominant senile dementia”, are imprecise and not appropriate for most subjects. PART is almost universally detectable at autopsy among elderly individuals, yet this pathological process cannot be specifically identified pre-mortem at the present time. Improved biomarkers and tau imaging may enable diagnosis of PART in clinical settings in the future. Indeed, recent studies have identified a common biomarker profile consisting of temporal lobe atrophy and tauopathy without evidence of Aβ accumulation. For both researchers and clinicians, a revised nomenclature will raise awareness of this extremely common pathologic change while providing a conceptual foundation for future studies. Prior reports that have elucidated features of the pathologic entity we refer to as PART are discussed, and working neuropathological diagnostic criteria are proposed. PMID:25348064

  15. Camarada and Thomas on middeck

    NASA Image and Video Library

    2005-08-07

    S114-E-7001 (4 August 2005) --- Astronaut Andrew S. W. Thomas, STS-114 mission specialist, photographs a middeck evaluation of the mechanical "plug" option for Reinforced Carbon-Carbon (RCC) repair aboard the Space Shuttle Discovery. Astronaut Charles J. Camarda, mission specialist, uses special pre-designated tools to accomplish the procedure, along with round thin, flexible 7-inch-diamter carbon-silicon cover plates designed to flex up to 0.25 inch to conform to the wing leading edge RCC panels, a hardware attachment mechanism similar to a toggle bolt and sealant.

  16. Thomas and Camarda on middeck

    NASA Image and Video Library

    2005-08-04

    S114-E-7005 (4 August 2005) --- Astronaut Andrew S. W. Thomas, STS-114 mission specialist, photographs a middeck evaluation of the mechanical "plug" option for Reinforced Carbon-Carbon (RCC) repair aboard the Space Shuttle Discovery. Astronaut Charles J. Camarda, mission specialist, uses special pre-designated tools to accomplish the procedure, along with round thin, flexible 7-inch-diamter carbon-silicon cover plates designed to flex up to 0.25 inch to conform to the wing leading edge RCC panels, a hardware attachment mechanism similar to a toggle bolt and sealant.

  17. Mind the GAP: A Novel Tumor-Promoting Mechanism | Center for Cancer Research

    Cancer.gov

    RAS proteins, like light switches, toggle between an “on” conformation where they promote cell growth, survival, and/or the formation of blood vessels (known as angiogenesis) and an “off” conformation in which they are unable to stimulate their target effector proteins. Nearly one-third of human tumors express a mutated RAS gene, which encodes a protein locked permanently in the active state. Other tumors, including liver hepatocellular carcinomas (HCCs), display aberrant RAS pathway signaling but lack RAS gene mutations, suggesting alternative mechanisms for this excessive RAS activity.

  18. Liver Hemangioma

    MedlinePlus

    Liver hemangioma Overview A liver hemangioma (he-man-jee-O-muh) is a noncancerous (benign) mass in the liver. A liver hemangioma is made up of a tangle of blood vessels. Other terms for a liver hemangioma are hepatic hemangioma and cavernous hemangioma. Most ...

  19. Association between Traumatic Brain Injury and Late Life Neurodegenerative Conditions and Neuropathological Findings

    PubMed Central

    Crane, Paul K.; Gibbons, Laura E.; Dams-O’Connor, Kristen; Trittschuh, Emily; Leverenz, James B.; Keene, C. Dirk; Sonnen, Joshua; Montine, Thomas J.; Bennett, David A.; Leurgans, Sue; Schneider, Julie A.; Larson, Eric B.

    2016-01-01

    IMPORTANCE There is great interest in the late effects of traumatic brain injury (TBI). OBJECTIVE To determine whether TBI with loss of consciousness (LOC) is associated with increased risk for clinical and neuropathological findings of Alzheimer’s disease, Parkinson’s disease, and other dementias. Our primary hypothesis was that TBI with LOC would be associated with increased risk for Alzheimer’s disease and neurofibrillary tangles. DESIGN Prospective cohort studies which follow all participants (Religious Orders Study and the Memory and Aging Project, ROS and MAP) or all consenting participants (Adult Changes in Thought, ACT) to autopsy. Studies performed annual (ROS and MAP) or biennial (ACT) cognitive and clinical testing to identify incident cases of dementia and Alzheimer’s disease. SETTING Members of a Seattle-area healthcare delivery system (ACT); priests and nuns living in orders across the US (ROS), and Chicago-area adults in retirement communities (MAP). PARTICIPANTS 7,130 older adults; 1,589 came to autopsy. EXPOSURE Self reported TBI reported when free of dementia, categorized as <1 hour vs. > 1 hour of LOC. MAIN OUTCOMES AND MEASURES Clinical: incident all-cause dementia, Alzheimer’s disease, and Parkinson’s disease (all studies), and incident mild cognitive impairment and progression of parkinsonian signs (ROS and MAP). Neuropathology: neurofibrillary tangles, neuritic plaques, microinfarcts, cystic infarcts, Lewy bodies, and hippocampal sclerosis (all studies). RESULTS 865 participants reported a history of TBI with LOC. In >45,000 person-years of follow-up, there were 1,537 incident dementia and 117 incident Parkinson’s disease cases. There was no association between TBI with LOC and incident dementia or Alzheimer’s disease. There were associations between TBI with LOC and incident Parkinson’s disease and progression of parkinsonian signs. There was no association between TBI with LOC and neurofibrillary tangles or neuritic plaques. There was an association between TBI with LOC and Lewy bodies, and with microinfarcts, though numbers of people with these findings were small. CONCLUSIONS AND RELEVANCE Pooled clinical and neuropathology data from three prospective cohort studies indicate that TBI with LOC is associated with risk of Lewy body accumulation, progression of parkinsonism, and Parkinson’s disease, but not dementia, Alzheimer’s disease, neuritic plaques, or neurofibrillary tangles. PMID:27400367

  20. TSCA Section 21 Petition Requesting EPA to Regulate Lead in Fishing Tackle

    EPA Pesticide Factsheets

    This petition requests EPA to promulgate regulations under section 6 of TSCA to protect the environment from fishing tackle containing lead including fishing weights, sinkers, lures, jigs, and/or other tackle.

  1. In Search of the Object: Historiography and Adult Education.

    ERIC Educational Resources Information Center

    Welton, Michael R.

    1993-01-01

    Historical inquiry in adult education is tangled up with contemporary debates about the nature of the field as a discipline. The problem of object and the problem of usability must be considered for historical insights to inform the field. (SK)

  2. Tackling antibiotic resistance in India.

    PubMed

    Wattal, Chand; Goel, Neeraj

    2014-12-01

    Infectious diseases are major causes of mortality in India. This is aggravated by the increasing prevalence of antimicrobial resistance (AMR) both in the community and in hospitals. Due to the emergence of resistance to all effective antibiotics in nosocomial pathogens, the situation calls for emergency measures to tackle AMR in India. India has huge challenges in tackling AMR, ranging from lack of surveillance mechanisms for monitoring AMR and use; effective hospital control policies; sanitation and non-human use of antimicrobial. The Ministry of Health and Family Welfare of Govt. of India has taken initiatives to tackle AMR. Extensive guidelines have been drafted and a model worksheet has been developed as a roadmap to tackle AMR.

  3. Comparative short-term effects of two thoracic spinal manipulation techniques in subjects with chronic mechanical neck pain: a randomized controlled trial.

    PubMed

    Casanova-Méndez, Amaloha; Oliva-Pascual-Vaca, Angel; Rodriguez-Blanco, Cleofás; Heredia-Rizo, Alberto Marcos; Gogorza-Arroitaonandia, Kristobal; Almazán-Campos, Ginés

    2014-08-01

    Spinal Manipulation (SM) has been purported to decrease pain and improve function in subjects with non-specific neck pain. Previous research has investigated which individuals with non-specific neck pain will be more likely to benefit from SM. It has not yet been proven whether or not the effectiveness of thoracic SM depends on the specific technique being used. This double-blind randomized trial has compared the short-term effects of two thoracic SM maneuvers in subjects with chronic non-specific neck pain. Sixty participants were distributed randomly into two groups. One group received the Dog technique (n = 30), with the subject in supine position, and the other group underwent the Toggle-Recoil technique (n = 30), with the participant lying prone, T4 being the targeted area in both cases. Evaluations were made of self-reported neck pain (Visual Analogue Scale); neck mobility (Cervical Range of Motion); and pressure pain threshold at the cervical and thoracic levels (C4 and T4 spinous process) and over the site described for location of tense bands of the upper trapezius muscle. Measurements were taken before intervention, immediately afterward, and 20 min later. Both maneuvers improved neck mobility and mechanosensitivity and reduced pain in the short term. No major or clinical differences were found between the groups. In the between-groups comparison slightly better results were observed in the Toggle-Recoil group only for cervical extension (p = 0.009), right lateral flexion (p = 0.004) and left rotation (p < 0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Operating principles of tristable circuits regulating cellular differentiation

    NASA Astrophysics Data System (ADS)

    Jia, Dongya; Jolly, Mohit Kumar; Harrison, William; Boareto, Marcelo; Ben-Jacob, Eshel; Levine, Herbert

    2017-06-01

    Many cell-fate decisions during embryonic development are governed by a motif comprised of two transcription factors (TFs) A and B that mutually inhibit each other and may self-activate. This motif, called as a self-activating toggle switch (SATS), can typically have three stable states (phenotypes)—two corresponding to differentiated cell fates, each of which has a much higher level of one TF than the other—≤ft(A,~B\\right)=≤ft(1,~0\\right) or ≤ft(0,~1\\right) —and the third state corresponding to an ‘undecided’ stem-like state with similar levels of both A and B—≤ft(A,~B\\right)=≤ft(1/2,1/2\\right) . Furthermore, two or more SATSes can be coupled together in various topologies in different contexts, thereby affecting the coordination between multiple cellular decisions. However, two questions remain largely unanswered: (a) what governs the co-existence and relative stability of these three stable states? (b) What orchestrates the decision-making of coupled SATSes? Here, we first demonstrate that the co-existence and relative stability of the three stable states in an individual SATS can be governed by the relative strength of self-activation, external signals activating and/or inhibiting A and B, and mutual degradation between A and B. Simultaneously, we investigate the effects of these factors on the decision-making of two coupled SATSes. Our results offer novel understanding into the operating principles of individual and coupled tristable self-activating toggle switches (SATSes) regulating cellular differentiation and can yield insights into synthesizing three-way genetic circuits and understanding of cellular reprogramming.

  5. Loads Bias Genetic and Signaling Switches in Synthetic and Natural Systems

    PubMed Central

    Medford, June; Prasad, Ashok

    2014-01-01

    Biological protein interactions networks such as signal transduction or gene transcription networks are often treated as modular, allowing motifs to be analyzed in isolation from the rest of the network. Modularity is also a key assumption in synthetic biology, where it is similarly expected that when network motifs are combined together, they do not lose their essential characteristics. However, the interactions that a network module has with downstream elements change the dynamical equations describing the upstream module and thus may change the dynamic and static properties of the upstream circuit even without explicit feedback. In this work we analyze the behavior of a ubiquitous motif in gene transcription and signal transduction circuits: the switch. We show that adding an additional downstream component to the simple genetic toggle switch changes its dynamical properties by changing the underlying potential energy landscape, and skewing it in favor of the unloaded side, and in some situations adding loads to the genetic switch can also abrogate bistable behavior. We find that an additional positive feedback motif found in naturally occurring toggle switches could tune the potential energy landscape in a desirable manner. We also analyze autocatalytic signal transduction switches and show that a ubiquitous positive feedback switch can lose its switch-like properties when connected to a downstream load. Our analysis underscores the necessity of incorporating the effects of downstream components when understanding the physics of biochemical network motifs, and raises the question as to how these effects are managed in real biological systems. This analysis is particularly important when scaling synthetic networks to more complex organisms. PMID:24676102

  6. Risk factors for head injury events in professional rugby union: a video analysis of 464 head injury events to inform proposed injury prevention strategies.

    PubMed

    Tucker, Ross; Raftery, Martin; Kemp, Simon; Brown, James; Fuller, Gordon; Hester, Ben; Cross, Matthew; Quarrie, Ken

    2017-08-01

    The tackle is responsible for the majority of head injuries during rugby union. In order to address head injury risk, risk factors during the tackle must first be identified. This study analysed tackle characteristics in the professional game in order to inform potential interventions. 464 tackles resulting in a head injury assessment (HIA) were analysed in detail, with tackle type, direction, speed, acceleration, nature of head contact and player body position the characteristics of interest. Propensity to cause an HIA was significantly greater for active shoulder tackles, front-on tackles, high speeder tackles and an accelerating tackler. Head contact between a tackler's head and ball carrier's head or shoulder was significantly more likely to cause an HIA than contact below the level of the shoulder (incident rate ratio (IRR) 4.25, 95%-CI 3.38 to 5.35). The tackler experiences the majority (78%) of HIAs when head-to-head contact occurs. An upright tackler was 1.5 times more likely to experience an HIA than a bent at the waist tackler (IRR 1.44, 95% CI 1.18 to 1.76). This study confirms that energy transfer in the tackle is a risk factor for head injury, since direction, type and speed all influence HIA propensity. The study provides evidence that body position and the height of tackles should be a focus for interventions, since lowering height and adopting a bent at the waist body position is associated with reduced risk for both tacklers and ball carriers. To this end, World Rugby has implemented law change based on the present data. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  7. The Tangle of Student Allowances.

    ERIC Educational Resources Information Center

    Thomson, Norman J.

    1980-01-01

    A discussion of the distribution of student financial aid in Australia focuses on these issues: direct vs. indirect payment to students; inequality in living allowances given to secondary and postsecondary students; and distribution of expense allowances by state government and living allowances by the Commonwealth. (MSE)

  8. Baby Steps.

    ERIC Educational Resources Information Center

    Jones, Wendell H.

    1997-01-01

    A harried school counselor describes a tangled web of domestic discord and agency miscoordination (complicated by an unintelligible restraining order and a birth certificate mix-up) that try his patience and leave a young girl bereft of family. Dakota Stages's gutsiness and resiliency impress this counselor immensely. (MLH)

  9. Vertical leadership in highly complex and unpredictable health systems.

    PubMed

    Till, Alex; Dutta, Nina; McKimm, Judy

    2016-08-02

    This article explores how the concept of vertical leadership development might help health organizations cope with and thrive within highly complex and unpredictable health systems, looking at concepts of VUCA (volatility, uncertainty, complexity and ambiguity) and RUPT (rapid, unpredictable, paradoxical and tangled).

  10. Ultrastructural characteristics of tau filaments in tauopathies: immuno-electron microscopic demonstration of tau filaments in tauopathies.

    PubMed

    Arima, Kunimasa

    2006-10-01

    The microtubule-associated protein tau aggregates into filaments in the form of neurofibrillary tangles, neuropil threads and argyrophilic grains in neurons, in the form of variable astrocytic tangles in astrocytes and in the form of coiled bodies and argyrophilic threads in oligodendrocytes. These tau filaments may be classified into two types, straight filaments or tubules with 9-18 nm diameters and "twisted ribbons" composed of two parallel aligned components. In the same disease, the fine structure of tau filaments in glial cells roughly resembles that in neurons. In sporadic tauopathies, individual tau filaments show characteristic sizes, shapes and arrangements, and therefore contribute to neuropathologic differential diagnosis. In frontotemporal dementias caused by tau gene mutations, variable filamentous profiles were observed in association with mutation sites and insoluble tau isoforms, including straight filaments or tubules, paired helical filament-like filaments, and twisted ribbons. Pre-embedding immunoelectron microscopic studies were carried out using anti-3-repeat tau and anti-4-repeat tau specific antibodies, RD3 and RD4. Straight tubules in neuronal and astrocytic Pick bodies were immunolabeled by the anti-3-repeat tau antibody. The anti-4-repeat tau antibody recognized abnormal tubules comprising neurofibrillary tangles, coiled bodies and argyrophilic threads in progressive supranuclear palsy (PSP) and corticobasal degeneration. In the pre-embedding immunoelectron microscopic study using the phosphorylated tau AT8 antibody, tuft-shaped astrocytes of PSP were found to be composed of bundles of abnormal tubules in processes and perikarya of protoplasmic astrocytes. In this study, the 3-repeat tau or 4-repeat tau epitope was detected in situ at the ultrastructural level in abnormal tubules in representative pathological lesions in Pick's disease, PSP and corticobasal degeneration.

  11. Age- and disease-dependent increase of the mitophagy marker phospho-ubiquitin in normal aging and Lewy body disease.

    PubMed

    Hou, Xu; Fiesel, Fabienne C; Truban, Dominika; Castanedes Casey, Monica; Lin, Wen-Lang; Soto, Alexandra I; Tacik, Pawel; Rousseau, Linda G; Diehl, Nancy N; Heckman, Michael G; Lorenzo-Betancor, Oswaldo; Ferrer, Isidre; Arbelo, José M; Steele, John C; Farrer, Matthew J; Cornejo-Olivas, Mario; Torres, Luis; Mata, Ignacio F; Graff-Radford, Neill R; Wszolek, Zbigniew K; Ross, Owen A; Murray, Melissa E; Dickson, Dennis W; Springer, Wolfdieter

    2018-06-27

    Although exact causes of Parkinson disease (PD) remain enigmatic, mitochondrial dysfunction is increasingly appreciated as a key determinant of dopaminergic neuron susceptibility in both familial and sporadic PD. Two genes associated with recessive, early-onset PD encode the ubiquitin (Ub) kinase PINK1 and the E3 Ub ligase PRKN/PARK2/Parkin, which together orchestrate a protective mitochondrial quality control (mitoQC) pathway. Upon stress, both enzymes cooperatively identify and decorate damaged mitochondria with phosphorylated poly-Ub (p-S65-Ub) chains. This specific label is subsequently recognized by autophagy receptors that further facilitate mitochondrial degradation in lysosomes (mitophagy). Here, we analyzed human post-mortem brain specimens and identified distinct pools of p-S65-Ub-positive structures that partially colocalized with markers of mitochondria, autophagy, lysosomes and/or granulovacuolar degeneration bodies. We further quantified levels and distribution of the 'mitophagy tag' in 2 large cohorts of brain samples from normal aging and Lewy body disease (LBD) cases using unbiased digital pathology. Somatic p-S65-Ub structures independently increased with age and disease in distinct brain regions and enhanced levels in LBD brain were age- and Braak tangle stage-dependent. Additionally, we observed significant correlations of p-S65-Ub with LBs and neurofibrillary tangle levels in disease. The degree of co-existing p-S65-Ub signals and pathological PD hallmarks increased in the pre-mature stage, but decreased in the late stage of LB or tangle aggregation. Altogether, our study provides further evidence for a potential pathogenic overlap among different forms of PD and suggests that p-S65-Ub can serve as a biomarker for mitochondrial damage in aging and disease.

  12. Cerebral amyloid-beta protein accumulation with aging in cotton-top tamarins: a model of early Alzheimer's disease?

    PubMed

    Lemere, Cynthia A; Oh, Jiwon; Stanish, Heather A; Peng, Ying; Pepivani, Imelda; Fagan, Anne M; Yamaguchi, Haruyasu; Westmoreland, Susan V; Mansfield, Keith G

    2008-04-01

    Alzheimer's disease (AD) is the most common progressive form of dementia in the elderly. Two major neuropathological hallmarks of AD include cerebral deposition of amyloid-beta protein (Abeta) into plaques and blood vessels, and the presence of neurofibrillary tangles in brain. In addition, activated microglia and reactive astrocytes are often associated with plaques and tangles. Numerous other proteins are associated with plaques in human AD brain, including Apo E and ubiquitin. The amyloid precursor protein and its shorter fragment, Abeta, are homologous between humans and non-human primates. Cerebral Abeta deposition has been reported previously for rhesus monkeys, vervets, squirrel monkeys, marmosets, lemurs, cynomologous monkeys, chimpanzees, and orangutans. Here we report, for the first time, age-related neuropathological changes in cotton-top tamarins (CTT, Saguinus oedipus), an endangered non-human primate native to the rainforests of Colombia and Costa Rica. Typical lifespan is 13-14 years of age in the wild and 15-20+ years in captivity. We performed detailed immunohistochemical analyses of Abeta deposition and associated pathogenesis in archived brain sections from 36 tamarins ranging in age from 6-21 years. Abeta plaque deposition was observed in 16 of the 20 oldest tamarins (>12 years). Plaques contained mainly Abeta42, and in the oldest animals, were associated with reactive astrocytes, activated microglia, Apo E, and ubiquitin-positive dystrophic neurites, similar to human plaques. Vascular Abeta was detected in 14 of the 20 aged tamarins; Abeta42 preceded Abeta40 deposition. Phospho-tau labeled dystrophic neurites and tangles, typically present in human AD, were absent in the tamarins. In conclusion, tamarins may represent a model of early AD pathology.

  13. Neuropathologic features associated with Alzheimer disease diagnosis

    PubMed Central

    Grinberg, L.T.; Miller, B.; Kawas, C.; Yaffe, K.

    2011-01-01

    Objective: To examine whether the association between clinical Alzheimer disease (AD) diagnosis and neuropathology and the precision by which neuropathology differentiates people with clinical AD from those with normal cognition varies by age. Methods: We conducted a cross-sectional analysis of 2,014 older adults (≥70 years at death) from the National Alzheimer's Coordinating Center database with clinical diagnosis of normal cognition (made ≤1 year before death, n = 419) or AD (at ≥65 years, n = 1,595) and a postmortem neuropathologic examination evaluating AD pathology (neurofibrillary tangles, neuritic plaques) and non-AD pathology (diffuse plaques, amyloid angiopathy, Lewy bodies, macrovascular disease, microvascular disease). We used adjusted logistic regression to analyze the relationship between clinical AD diagnosis and neuropathologic features, area under the receiver operating characteristic curve (c statistic) to evaluate how precisely neuropathology differentiates between cognitive diagnoses, and an interaction to identify effect modification by age group. Results: In a model controlling for coexisting neuropathologic features, the relationship between clinical AD diagnosis and neurofibrillary tangles was significantly weaker with increasing age (p < 0.001 for interaction). The aggregate of all neuropathologic features more strongly differentiated people with clinical AD from those without in younger age groups (70–74 years: c statistic, 95% confidence interval: 0.93, 0.89–0.96; 75–84 years: 0.95, 0.87–0.95; ≥85 years: 0.83, 0.80–0.87). Non-AD pathology significantly improved precision of differentiation across all age groups (p < 0.004). Conclusion: Clinical AD diagnosis was more weakly associated with neurofibrillary tangles among the oldest old compared to younger age groups, possibly due to less accurate clinical diagnosis, better neurocompensation, or unaccounted pathology among the oldest old. PMID:22031532

  14. Regional Geochemical Results from Analyses of Stream-Water, Stream-Sediment, Soil, Soil-Water, Bedrock, and Vegetation Samples, Tangle Lakes District, Alaska

    USGS Publications Warehouse

    Wang, Bronwen; Gough, L.P.; Wanty, R.B.; Lee, G.K.; Vohden, James; O'Neill, J. M.; Kerin, L.J.

    2008-01-01

    We report chemical analyses of stream-water, stream-sediment, soil, soil-water, bedrock, and vegetation samples collected from the headwaters of the Delta River (Tangle Lakes District, Mount Hayes 1:250,000-scale quadrangle) in east-central Alaska for the period June 20-25, 2006. Additionally, we present mineralogic analyses of stream sediment, concentrated by panning. The study area includes the southwestward extent of the Bureau of Land Management (BLM) Delta River Mining District (Bittenbender and others, 2007), including parts of the Delta River Archeological District, and encompasses an area of about 500 km2(approximately bordered by the Denali Highway to the south, near Round Tangle Lake, northward to the foothills of the Alaska Range (fig. 1). The primary focus of this study was the chemical characterization of native materials, especially surface-water and sediment samples, of first-order streams from the headwaters of the Delta River. The impetus for this work was the need, expressed by the Alaska Department of Natural Resources (ADNR), for an inventory of geochemical and hydrogeochemical baseline information about the Delta River Mining District. This information is needed because of a major upturn in exploration, drilling, and general mineral-resources assessments in the region since the late 1990s. Currently, the study area, called the 'MAN Project' area is being explored by Pure Nickel, Inc. (http://www.purenickel.com/s/MAN_Alaska.asp), and includes both Cu-Au-Ag and Ni-Cu-PGE (Pt-Pd-Au-Ag) mining claims. Geochemical data on surface-water, stream-sediment, soil, soil-water, grayleaf willow (Salix glauca L.), and limited bedrock samples are provided along with the analytical methodologies used and panned-concentrate mineralogy. We are releasing the data at this time with only minimal interpretation.

  15. Evaluation of 8-week body weight control program including sea tangle (Laminaria japonica) supplementation in Korean female college students

    PubMed Central

    You, Jeong Soon; Sung, Min Jung

    2009-01-01

    This study was conducted to evaluate the effects of a body weight control program with supplementation of sea tangle (20 g/day) on 22 female college students. The contents of the program for 8 weeks contained diet therapy, exercise and behavioral modification through nutrition education. Body composition, dietary habit scores, serum lipid profiles, daily nutrient intakes and the quality of life were assessed at the beginning and at the end of the program. Average age of subjects and height were 20.8 years and 161.9 cm, respectively. After 8 weeks, there were significant reductions in body weight, body fat mass, percent body fat, waist-hip ratio and BMI. The dietary habit score such as a balanced diet, regularity of mealtime, overeating, eating while watching TV or using the computer and eating salty food were increased significantly. Serum lipid levels such as total cholesterol level, LDL-cholesterol level and triglyceride level were decreased but not significantly. There were decreases in intake of energy, protein and fat and increases in intakes of dietary fiber, folic acid, calcium and potassium from the beginning to the end of the program. There were significant improvements on subcomponents of quality of life; physical functioning, general-health and vitality. The limitation of this study was the fact that there was no control group, but an overall evaluation suggests the 8-week body weight control program consisting of diet therapy, exercise and behavioral modification with supplementation of sea tangle would be helpful to improve the body composition, dietary habits, daily nutrient intakes and quality of life in Korean female college students. PMID:20098584

  16. IS THE SMALL-SCALE MAGNETIC FIELD CORRELATED WITH THE DYNAMO CYCLE?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karak, Bidya Binay; Brandenburg, Axel, E-mail: bbkarak@nordita.org

    2016-01-01

    The small-scale magnetic field is ubiquitous at the solar surface—even at high latitudes. From observations we know that this field is uncorrelated (or perhaps even weakly anticorrelated) with the global sunspot cycle. Our aim is to explore the origin, and particularly the cycle dependence, of such a phenomenon using three-dimensional dynamo simulations. We adopt a simple model of a turbulent dynamo in a shearing box driven by helically forced turbulence. Depending on the dynamo parameters, large-scale (global) and small-scale (local) dynamos can be excited independently in this model. Based on simulations in different parameter regimes, we find that, when onlymore » the large-scale dynamo is operating in the system, the small-scale magnetic field generated through shredding and tangling of the large-scale magnetic field is positively correlated with the global magnetic cycle. However, when both dynamos are operating, the small-scale field is produced from both the small-scale dynamo and the tangling of the large-scale field. In this situation, when the large-scale field is weaker than the equipartition value of the turbulence, the small-scale field is almost uncorrelated with the large-scale magnetic cycle. On the other hand, when the large-scale field is stronger than the equipartition value, we observe an anticorrelation between the small-scale field and the large-scale magnetic cycle. This anticorrelation can be interpreted as a suppression of the small-scale dynamo. Based on our studies we conclude that the observed small-scale magnetic field in the Sun is generated by the combined mechanisms of a small-scale dynamo and tangling of the large-scale field.« less

  17. Severe and Catastrophic Neck Injuries Resulting from Tackle Football

    ERIC Educational Resources Information Center

    Torg, Joseph S.; And Others

    1977-01-01

    Use of the spring-loaded blocking and tackling devices should be discontinued due to severe neck injuries resulting from their use; employment of the head and helmet as the primary assault weapon in blocking, tackling, and head butting should be condemned for the same reason. (MJB)

  18. Sellers holds up a bundle of tangled audio cables during STS-121 / Expedition 13 joint operations

    NASA Image and Video Library

    2006-07-15

    S121-E-07791 (15 July 2006) --- Astronaut Piers J. Sellers, STS-121 mission specialist, works with cables on the middeck of Space Shuttle Discovery as the shuttle crew prepares to undock from the International Space Station.

  19. 7 CFR 29.6027 - Nested.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INSPECTION Standards Definitions § 29.6027 Nested. Any tobacco which has been loaded, packed, or arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior tobacco, any of...

  20. 7 CFR 29.6027 - Nested.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INSPECTION Standards Definitions § 29.6027 Nested. Any tobacco which has been loaded, packed, or arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior tobacco, any of...

  1. 7 CFR 29.6027 - Nested.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INSPECTION Standards Definitions § 29.6027 Nested. Any tobacco which has been loaded, packed, or arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior tobacco, any of...

  2. 7 CFR 29.6027 - Nested.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INSPECTION Standards Definitions § 29.6027 Nested. Any tobacco which has been loaded, packed, or arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior tobacco, any of...

  3. T-Shirt Tangle.

    ERIC Educational Resources Information Center

    Clark, Wilma

    1986-01-01

    Describes an exercise in which students cut out T-shirt drawings, sort the T-shirts into groups, and "write" a classification essay by pasting the T-shirts on sheet of paper. The T-shirts in each group become the examples used in one body paragraph of the classification essay. (HTH)

  4. 7 CFR 30.8 - Scrap.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.8 Scrap. A byproduct from handling leaf tobacco in both the unstemmed and stemmed forms, consisting of loose and tangled portions of tobacco leaves, floor sweepings, and all other tobacco materials (except stems...

  5. 7 CFR 30.8 - Scrap.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.8 Scrap. A byproduct from handling leaf tobacco in both the unstemmed and stemmed forms, consisting of loose and tangled portions of tobacco leaves, floor sweepings, and all other tobacco materials (except stems...

  6. 7 CFR 30.8 - Scrap.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.8 Scrap. A byproduct from handling leaf tobacco in both the unstemmed and stemmed forms, consisting of loose and tangled portions of tobacco leaves, floor sweepings, and all other tobacco materials (except stems...

  7. 7 CFR 30.8 - Scrap.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.8 Scrap. A byproduct from handling leaf tobacco in both the unstemmed and stemmed forms, consisting of loose and tangled portions of tobacco leaves, floor sweepings, and all other tobacco materials (except stems...

  8. 7 CFR 30.8 - Scrap.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... AND STANDARDS Classification of Leaf Tobacco Covering Classes, Types and Groups of Grades § 30.8 Scrap. A byproduct from handling leaf tobacco in both the unstemmed and stemmed forms, consisting of loose and tangled portions of tobacco leaves, floor sweepings, and all other tobacco materials (except stems...

  9. Tangled trios? Characterizing a hybrid zone in Castilleja (Orobanchaceae)

    Treesearch

    Erika l. Hersch-Green; Richard Cronn

    2009-01-01

    Hybridization and polyploidization are exceedingly important processes because both influence the ecological envelope and evolutionary trajectory of land plants. These processes are frequently invoked for Castilleja (Indian paintbrushes) as contributors to morphological and genetic novelty and as complicating factors in species delimitations. Here...

  10. Probing the correlation of neuronal loss, neurofibrillary tangles, and cell death markers across the Alzheimer's disease Braak stages: a quantitative study in humans.

    PubMed

    Theofilas, Panos; Ehrenberg, Alexander J; Nguy, Austin; Thackrey, Julia M; Dunlop, Sara; Mejia, Maria B; Alho, Ana T; Paraizo Leite, Renata Elaine; Rodriguez, Roberta Diehl; Suemoto, Claudia K; Nascimento, Camila F; Chin, Marcus; Medina-Cleghorn, Daniel; Cuervo, Ana Maria; Arkin, Michelle; Seeley, William W; Miller, Bruce L; Nitrini, Ricardo; Pasqualucci, Carlos Augusto; Filho, Wilson Jacob; Rueb, Udo; Neuhaus, John; Heinsen, Helmut; Grinberg, Lea T

    2018-01-01

    Clarifying the mechanisms connecting neurofibrillary tangle (NFT) neurotoxicity to neuronal dysfunction in humans is likely to be pivotal for developing effective treatments for Alzheimer's disease (AD). To model the temporal progression of AD in humans, we used a collection of brains with controls and individuals from each Braak stage to quantitatively investigate the correlation between intraneuronal caspase activation or macroautophagy markers, NFT burden, and neuronal loss, in the dorsal raphe nucleus and locus coeruleus, the earliest vulnerable areas to NFT accumulation. We fit linear regressions with each count as outcomes, with Braak score and age as the predictors. In progressive Braak stages, intraneuronal active caspase-6 positivity increases both alone and overlapping with NFTs. Likewise, the proportion of NFT-bearing neurons showing autophagosomes increases. Overall, caspases may be involved in upstream cascades in AD and are associated with higher NFTs. Macroautophagy changes correlate with increasing NFT burden from early AD stages. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Long-term biopersistence of tangled oxidized carbon nanotubes inside and outside macrophages in rat subcutaneous tissue

    NASA Astrophysics Data System (ADS)

    Sato, Yoshinori; Yokoyama, Atsuro; Nodasaka, Yoshinobu; Kohgo, Takao; Motomiya, Kenichi; Matsumoto, Hiroaki; Nakazawa, Eiko; Numata, Tomoko; Zhang, Minfang; Yudasaka, Masako; Hara, Hideyuki; Araki, Rikita; Tsukamoto, Osamu; Saito, Hiroaki; Kamino, Takeo; Watari, Fumio; Tohji, Kazuyuki

    2013-08-01

    Because of their mechanical strength, chemical stability, and low molecular weight, carbon nanotubes (CNTs) are attractive biological implant materials. Biomaterials are typically implanted into subcutaneous tissue or bone; however, the long-term biopersistence of CNTs in these tissues is unknown. Here, tangled oxidized multi-walled CNTs (t-ox-MWCNTs) were implanted into rat subcutaneous tissues and structural changes in the t-ox-MWCNTs located inside and outside of macrophages were studied for 2 years post-implantation. The majority of the large agglomerates were present in the intercellular space, maintained a layered structure, and did not undergo degradation. By contrast, small agglomerates were found inside macrophages, where they were gradually degraded in lysosomes. None of the rats displayed symptoms of cancer or severe inflammatory reactions such as necrosis. These results indicate that t-ox-MWCNTs have high biopersistence and do not evoke adverse events in rat subcutaneous tissue in vivo, demonstrating their potential utility as implantable biomaterials.

  12. The Tangled Branches (Las Ramas Enredadas): Sexual Risk, Substance Abuse, and Intimate Partner Violence Among Hispanic Men who Have Sex with Men

    PubMed Central

    De Santis, Joseph P.; Gonzalez-Guarda, Rosa; Provencio-Vasquez, Elias; Deleon, Diego A.

    2012-01-01

    Hispanic men who have sex with men (MSM) experience a number of health disparities including high rates of HIV infection from high risk sex, substance abuse, and intimate partner violence. Although some research is available to document the relationships of these health disparities in the literature, few studies have explored the intersection of these disparities and the factors that influence them. The purpose of this study was to explore the experiences that Hispanic MSM residing in South Florida have with high risk sex, substance abuse, and intimate partner violence. Focus groups were conducted and analyzed using grounded theory methodology until data saturation was reached (n = 20). Two core categories with subcategories emerged from the data: The Roots of Risk (Los raices del riesgo) and The Tangled Branches (Las Ramas Enredadas). The results of the study provided some important clinical implications as well as directions for future research with Hispanic MSM. PMID:24084703

  13. Tangled up Active Region

    NASA Image and Video Library

    2017-12-08

    This close-up image of the sun presents an active region in profile as it rotated out of view. We can observe both the bright arching field lines and smaller pieces of darker matter in their midst being pulled back and forth just above the Sun's surface over about 36 hours (July 20-22, 2011). Both of these physical responses were caused by strong, tangled magnetic forces that are constantly evolving and reorganizing within the active region. Other active regions can be seen in the foreground as well. The image and movie were taken in extreme ultraviolet light of ionized iron heated to one million degrees. To view a hd video of this event go here: www.flickr.com/photos/gsfc/6006013038 Credit: NASA/GSFC/SDO NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  14. Avalanche of entanglement and correlations at quantum phase transitions.

    PubMed

    Krutitsky, Konstantin V; Osterloh, Andreas; Schützhold, Ralf

    2017-06-16

    We study the ground-state entanglement in the quantum Ising model with nearest neighbor ferromagnetic coupling J and find a sequential increase of entanglement depth d with growing J. This entanglement avalanche starts with two-point entanglement, as measured by the concurrence, and continues via the three-tangle and four-tangle, until finally, deep in the ferromagnetic phase for J = ∞, arriving at a pure L-partite (GHZ type) entanglement of all L spins. Comparison with the two, three, and four-point correlations reveals a similar sequence and shows strong ties to the above entanglement measures for small J. However, we also find a partial inversion of the hierarchy, where the four-point correlation exceeds the three- and two-point correlations, well before the critical point is reached. Qualitatively similar behavior is also found for the Bose-Hubbard model, suggesting that this is a general feature of a quantum phase transition. This should be taken into account in the approximations starting from a mean-field limit.

  15. The Tangled Branches (Las Ramas Enredadas): sexual risk, substance abuse, and intimate partner violence among Hispanic men who have sex with men.

    PubMed

    De Santis, Joseph P; Gonzalez-Guarda, Rosa; Provencio-Vasquez, Elias; Deleon, Diego A

    2014-01-01

    Hispanic men who have sex with men (MSM) experience a number of health disparities including high rates of HIV infection from high-risk sex, substance abuse, and intimate partner violence. Although some research is available to document the relationships of these health disparities in the literature, few studies have explored the intersection of these disparities and the factors that influence them. The purpose of this study was to explore the experiences that Hispanic MSM residing in South Florida have with high-risk sex, substance abuse, and intimate partner violence. Focus groups were conducted and analyzed using grounded theory methodology until data saturation was reached (n = 20). Two core categories with subcategories emerged from the data: The Roots of Risk (Los raices del riesgo) and The Tangled Branches (Las Ramas Enredadas). The results of the study provided some important clinical implications as well as directions for future research with Hispanic MSM.

  16. Brain Tocopherols Related to Alzheimer Disease Neuropathology in Humans

    PubMed Central

    Morris, Martha Clare; Schneider, Julie A; Li, Hong; Tangney, Christy C; Nag, Sukrit; Bennett, David A; Honer, William G.; Barnes, Lisa

    2014-01-01

    Randomized trials of α-tocopherol supplements on cognitive decline are negative whereas studies of dietary tocopherols show benefit. We investigated these inconsistencies by analyzing the relations of α- and γ-tocopherol brain concentrations to Alzheimer disease (AD) neuropathology among 115 deceased participants of the prospective Rush Memory and Aging Project. Associations of amyloid load and neurofibrillary tangle severity with brain tocopherol concentrations were examined in separate adjusted linear regression models. γ-tocopherol concentrations were associated with lower amyloid load (β= −2.10; p=.002) and lower neurofibrillary tangle severity (β= −1.16; p=0.02). Concentrations of α-tocopherol were not associated with AD neuropathology except as modified by γ-tocopherol: high α-tocopherol was associated with higher amyloid load when γ-tocopherol levels were low and with lower amyloid levels when γ-tocopherol levels were high (P for interaction=0.03). Brain concentrations of γ- and α-tocopherols may be associated with AD neuropathology in interrelated, complex ways. Randomized trials should consider the contribution of γ-tocopherol. PMID:24589434

  17. Mammalian chiasma frequencies as a test of two theories of recombination.

    PubMed

    Burt, A; Bell, G

    A broad survey of asexuality in the animal kingdom is sufficient to reject all theories of sex and recombination except two: the Red Queen and the Tangled Bank. The Red Queen theory states that an organism's biotic environment tends to be 'contrary', consistently evolving to the detriment of the organism; sex and recombination result in progeny genetically distinct from their parents and grandparents and thus less susceptible to the antagonistic advances made during the previous generations, particularly by their parasites. The alternative theory, the Tangled Bank, states that sex and recombination function to diversify the progeny from each other, thus reducing competition between them. An extensive survey of mammalian recombination shows that the total number of chiasmata in excess of one per bivalent is strongly correlated with generation time but uncorrelated with fecundity. We conclude that crossing-over may function to combat antagonists with short generation times but does not function to reduce sib competition. Chromosome number is selectively neutral with respect to these factors.

  18. Vortex arrays and ciliary tangles underlie the feeding-swimming tradeoff in starfish larvae

    NASA Astrophysics Data System (ADS)

    Gilpin, William; Prakash, Vivek N.; Prakash, Manu

    2016-11-01

    Many marine invertebrates have larval stages covered in linear arrays of beating cilia, which propel the animal while simultaneously entraining planktonic prey. These bands are strongly conserved across taxa spanning four major superphyla, and they are responsible for the unusual morphologies of many invertebrates. However, few studies have investigated their underlying hydrodynamics. Here, we study the ciliary bands of starfish larvae, and discover a beautiful pattern of slowly-evolving vortices that surrounds the swimming animals. Closer inspection of the bands reveals unusual ciliary "tangles" analogous to topological defects that break-up and re-form as the animal adjusts its swimming stroke. Quantitative experiments and modeling demonstrate that these vortices create a physical tradeoff between feeding and swimming in heterogenous environments, which manifests as distinct flow patterns or "eigenstrokes" representing each behavior-potentially implicating neuronal control of cilia. This quantitative interplay between larval form and hydrodynamic function generalizes to other invertebrates, and illustrates the potential effects of active boundary conditions in other biological and synthetic systems.

  19. 46 CFR 121.300 - Ground tackle and mooring lines.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Ground tackle and mooring lines. 121.300 Section 121.300 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE... MISCELLANEOUS SYSTEMS AND EQUIPMENT Mooring and Towing Equipment § 121.300 Ground tackle and mooring lines. A...

  20. High pressure induced crossover between metal and insulator conductivity type in low dimensionality electron systems

    NASA Astrophysics Data System (ADS)

    Dizhur, E.; Voronovskii, A.; Kostyleva, I.; Kotel'nikov, I.; Zaitsev-Zotov, S.

    2011-12-01

    We report the results of our recent experimental studies concerned with electron systems of lower dimensionality the conductivity of which may be toggled between metallic and insulating regime appliing high pressure. The objects under present study include: a) tunneling through Shottky barrier into two-dimension (2D) electron system formed in the δ-doped layer in GaAs under hydrostatic pressure up to 3 GPa in a cylinder-piston cell; b) quasi-one-dimension (1D) `insulator' crystals NbS3 which obtain metallic conductivity type at pressures above 5.5 GPa in `toroid' anvils.

  1. Real-space mapping of Fano interference in plasmonic metamolecules.

    PubMed

    Alonso-Gonzalez, Pablo; Schnell, Martin; Sarriugarte, Paulo; Sobhani, Heidar; Wu, Chihhui; Arju, Nihal; Khanikaev, Alexander; Golmar, Federico; Albella, Pablo; Arzubiaga, Libe; Casanova, Felix; Hueso, Luis E; Nordlander, Peter; Shvets, Gennady; Hillenbrand, Rainer

    2011-09-14

    An unprecedented control of the spectral response of plasmonic nanoantennas has recently been achieved by designing structures that exhibit Fano resonances. This new insight is paving the way for a variety of applications, such as biochemical sensing and surface-enhanced Raman spectroscopy. Here we use scattering-type near-field optical microscopy to map the spatial field distribution of Fano modes in infrared plasmonic systems. We observe in real space the interference of narrow (dark) and broad (bright) plasmonic resonances, yielding intensity and phase toggling between different portions of the plasmonic metamolecules when either their geometric sizes or the illumination wavelength is varied.

  2. 7 CFR 29.3533 - Nested.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign... arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes: (a) Any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior...

  3. 7 CFR 29.3533 - Nested.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign... arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes: (a) Any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior...

  4. 7 CFR 29.3533 - Nested.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign... arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes: (a) Any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior...

  5. 7 CFR 29.3533 - Nested.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INSPECTION Standards Official Standard Grades for Dark Air-Cured Tobacco (u.s. Types 35, 36, 37 and Foreign... arranged to conceal foreign matter or tobacco of inferior grade, quality, or condition. Nested includes: (a) Any lot of tobacco which contains foreign matter or damaged, injured, tangled, or other inferior...

  6. "Mississippi Trial, 1955": Tangling with Text through Reading, Discussion, and Writing

    ERIC Educational Resources Information Center

    Grierson, Sirpa; Thursby, Jacqueline S.; Dean, Deborah; Crowe, Chris

    2007-01-01

    The authors proffer practical critical-reading strategies for teaching "Mississippi Trial, 1955" to increase students' vocabulary, comprehension, and background knowledge of historical eras. They use nonfiction, a PBS documentary, the Web, folklore, and picture books among other tools for inciting thoughtful discussion and writing.

  7. Can we make a new deal? Entitlement reform sounds alluring, but the reality is stark.

    PubMed

    Wagner, L

    1995-01-20

    After simmering for more than a decade, the Great Entitlement Debate promises to dominate the 1995 congressional agenda. But lost amid a tangle of conflicting parochial interests, voter confusion and searing partisan rhetoric are some harsh truths about our options.

  8. Geometrically controlled evolution of four-qubit states

    NASA Astrophysics Data System (ADS)

    Duy, Hoang Ngoc; Heydari, Hoshang

    2011-03-01

    In this paper the evolution of some states of four qubits in [1] under global bipartite unitary operation and controlled by local unitary operation using four-tangle [2] and the geometric invariants [3] is investigated. Particularly the entanglement distribution and properties of these four-qubit states are studied.

  9. 7 CFR 29.6022 - Leaf scrap.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Leaf scrap. 29.6022 Section 29.6022 Agriculture... INSPECTION Standards Definitions § 29.6022 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. ...

  10. 7 CFR 29.6022 - Leaf scrap.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.6022 Section 29.6022 Agriculture... INSPECTION Standards Definitions § 29.6022 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. ...

  11. 7 CFR 29.6022 - Leaf scrap.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Leaf scrap. 29.6022 Section 29.6022 Agriculture... INSPECTION Standards Definitions § 29.6022 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. ...

  12. 7 CFR 29.6022 - Leaf scrap.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Leaf scrap. 29.6022 Section 29.6022 Agriculture... INSPECTION Standards Definitions § 29.6022 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. ...

  13. 7 CFR 29.6022 - Leaf scrap.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Leaf scrap. 29.6022 Section 29.6022 Agriculture... INSPECTION Standards Definitions § 29.6022 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. ...

  14. Collapsed scrums and collision tackles: what is the injury risk?

    PubMed

    Roberts, Simon P; Trewartha, Grant; England, Mike; Stokes, Keith A

    2015-04-01

    To establish the propensity for specific contact events to cause injury in rugby union. Medical staff at participating English community-level rugby clubs reported any injury resulting in the absence for one match or more from the day of the injury during the 2009/2010 (n=46), 2010/2011 (n=67) and 2011/2012 (n=76) seasons. Injury severity was defined as the number of matches missed. Thirty community rugby matches were filmed and the number of contact events (tackles, collision tackles, rucks, mauls, lineouts and scrums) recorded. Of 370 (95% CI 364 to 378) contact events per match, 141 (137 to 145) were tackles, 115 (111 to 119) were rucks and 32 (30 to 33) were scrums. Tackles resulted in the greatest propensity for injury (2.3 (2.2 to 2.4) injuries/1000 events) and the greatest severity (16 (15 to 17) weeks missed/1000 events). Collision tackles (illegal tackles involving a shoulder charge) had a propensity for injury of 15 (12.4 to 18.3) injuries/1000 events and severity was 92 (75 to 112) weeks missed/1000 events, both of which were higher than any other event. Additional scrum analysis showed that only 5% of all scrums collapsed, but the propensity for injury was four times higher (2.9 (1.5 to 5.4) injuries/1000 events) and the severity was six times greater (22 (12 to 42) weeks missed/1000 events) than for non-collapsed scrums. Injury prevention in the tackle should focus on technique with strict enforcement of existing laws for illegal collision tackles. The scrum is a relatively controllable event and further attempts should be made to reduce the frequency of scrum collapse. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. Evaluating behavioral skills training to teach safe tackling skills to youth football players.

    PubMed

    Tai, Sharayah S M; Miltenberger, Raymond G

    2017-10-01

    With concussion rates on the rise for football players, there is a need for further research to increase skills and decrease injuries. Behavioral skills training is effective in teaching a wide variety of skills but has yet to be studied in the sports setting. We evaluated behavioral skills training to teach safer tackling techniques to six participants from a Pop Warner football team. Safer tackling techniques increased during practice and generalized to games for the two participants who had opportunities to tackle in games. © 2017 Society for the Experimental Analysis of Behavior.

  16. Airport Traffic Conflict Detection and Resolution Algorithm Evaluation

    NASA Technical Reports Server (NTRS)

    Jones, Denise R.; Chartrand, Ryan C.; Wilson, Sara R.; Commo, Sean A.; Ballard, Kathryn M.; Otero, Sharon D.; Barker, Glover D.

    2016-01-01

    Two conflict detection and resolution (CD&R) algorithms for the terminal maneuvering area (TMA) were evaluated in a fast-time batch simulation study at the National Aeronautics and Space Administration (NASA) Langley Research Center. One CD&R algorithm, developed at NASA, was designed to enhance surface situation awareness and provide cockpit alerts of potential conflicts during runway, taxi, and low altitude air-to-air operations. The second algorithm, Enhanced Traffic Situation Awareness on the Airport Surface with Indications and Alerts (SURF IA), was designed to increase flight crew awareness of the runway environment and facilitate an appropriate and timely response to potential conflict situations. The purpose of the study was to evaluate the performance of the aircraft-based CD&R algorithms during various runway, taxiway, and low altitude scenarios, multiple levels of CD&R system equipage, and various levels of horizontal position accuracy. Algorithm performance was assessed through various metrics including the collision rate, nuisance and missed alert rate, and alert toggling rate. The data suggests that, in general, alert toggling, nuisance and missed alerts, and unnecessary maneuvering occurred more frequently as the position accuracy was reduced. Collision avoidance was more effective when all of the aircraft were equipped with CD&R and maneuvered to avoid a collision after an alert was issued. In order to reduce the number of unwanted (nuisance) alerts when taxiing across a runway, a buffer is needed between the hold line and the alerting zone so alerts are not generated when an aircraft is behind the hold line. All of the results support RTCA horizontal position accuracy requirements for performing a CD&R function to reduce the likelihood and severity of runway incursions and collisions.

  17. Synthetic metabolic bypass for a metabolic toggle switch enhances acetyl-CoA supply for isopropanol production by Escherichia coli.

    PubMed

    Soma, Yuki; Yamaji, Taiki; Matsuda, Fumio; Hanai, Taizo

    2017-05-01

    Almost all synthetic pathways for biofuel production are designed to require endogenous metabolites in glycolysis, such as phosphoenolpyruvate, pyruvate, and acetyl-CoA. However, such metabolites are also required for bacterial cell growth. To reduce the metabolic imbalance between cell growth and target chemical production, we previously constructed a metabolic toggle switch (MTS) as a conditional flux redirection tool controlling metabolic flux of TCA cycle toward isopropanol production. This approach succeeded to improve the isopropanol production titer and yield while ensuring sufficient cell growth. However, excess accumulation of pyruvate, the precursor for acetyl-CoA synthesis, was also observed. In this study, for efficient conversation of pyruvate to acetyl-CoA (pyruvate oxidation), we designed a synthetic metabolic bypass composed of poxB and acs with the MTS for acetyl-CoA supply from the excess pyruvate. When this designed bypass was expressed at the appropriate expression level associated with the conditional metabolic flux redirection, pyruvate accumulation was prevented, and the isopropanol production titer and yield were improved. Final isopropanol production titer of strain harboring MTS with the synthetic metabolic bypass improved 4.4-fold compared with strain without metabolic flux regulation, and it was 1.3-fold higher than that of strain harboring the conventional MTS alone. Additionally, glucose consumption was also improved 1.7-fold compared with strain without metabolic flux regulation. On the other hand, introduction of the synthetic metabolic bypass alone showed no improvement in isopropanol production and glucose consumption. These results showed that the improvement in bio-production process caused by synergy between the MTS and the synthetic metabolic bypass. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  18. LabVIEW Task Manager v. 1.10.0

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vargo, Timothy D.

    LabVIEW Task Manager is a debugging tool for use during code development in the National Instruments (NI) LabVIEW® IDE. While providing a dynamic & big-picture view of running code, an expandable/collapsible tree diagram displays detailed information (both static and dynamic) on all VIs in memory, belonging to a selected project/target. It allows for interacting with single or multiple selected VIs at a time, providing significant benefits while troubleshooting, and has the following features: Look & Feel similar to Windows® Task Manager; Selection of project/target; Lists all VIs in memory, grouped by class/library; Searches for and enumerates clones in memory; DropInmore » VI for including dynamically referenced clones (Clone Beacon); 'Refresh Now' (F5) re-reads all VIs in memory and adds new ones to the tree; Displays VI name, owning class/library, state, path, data size & code size; Displays VI FP Behavior, Reentrant?, Reentrancy Type, Paused? & Highlight?; Sort by any column, including by library name; Filter by item types vi, ctl, and vit/ctt; Filter out vi.lib and global VIs; Tracking of, and ability to toggle, execution highlighting on multiple selected VIs; Tracking of paused VIs with ability to Pause/Resume/TogglePause multiple selected VIs; DropIn VI for pausing on a condition; If a clone initiates a pause, a different pause symbol is used for all clones of that same reentrant original VI; Select multiple VIs and open or close their FPs or BDs; Double Click a VI from the tree to bring the BD (first choice) or FP to front, if already open; and Select multiple top-level VIs and Abort them.« less

  19. 7 CFR 29.3652 - Scrap (S Group).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Scrap (S Group). 29.3652 Section 29.3652 Agriculture... INSPECTION Standards Grades § 29.3652 Scrap (S Group). A byproduct of stemmed and unstemmed tobacco. Scrap... stemmeries. Grades Grade name and specifications S Scrap. Loose, tangled, whole, or broken unstemmed leaves...

  20. 7 CFR 29.2666 - Scrap (S Group).

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Scrap (S Group). 29.2666 Section 29.2666 Agriculture... INSPECTION Standards Grades § 29.2666 Scrap (S Group). A byproduct of unstemmed and stemmed tobacco. Scrap... stemmeries. Grades Grade names and specifications S Scrap. Tangled, whole, or broken unstemmed leaves, or the...

  1. Pedagogy Meets Digital Media: A Tangle of Teachers, Strategies, and Tactics

    ERIC Educational Resources Information Center

    Rust, Julie

    2017-01-01

    Although increasingly encouraged to incorporate digital media into classrooms to prepare students for engaged participation in a digital world, teachers are often taken by surprise when paradigm clashes arise between traditional school expectations and the affordances of these new spaces. Through data gathered from ethnographic methodologies…

  2. Does the dye Aquashade reduce pond production of sunshine bass fingerlings?

    USDA-ARS?s Scientific Manuscript database

    Rooted macrophytes make harvesting fingerling sunshine bass Morone chrysops × M. saxatilis difficult because they tangle in the seines and increase fish stress. Aquashade(c), a dye, is used to reduce macrophyte growth. Fingerling culturists are reluctant to use it because it may reduce phytoplank...

  3. A Tangled Path: Negotiating Leadership for, in, of, and with Diverse Communities

    ERIC Educational Resources Information Center

    Goddard, J. Tim

    2015-01-01

    This article addresses issues of educational leadership in postcolonial and post-conflict environments. The focus relates to large-scale testing protocols, diversity in schools, asset-based community development, and communications technology. The article highlights the importance of context to the tenets of social justice, equitable human…

  4. Approaching messy problems: strategies for environmental analysis

    Treesearch

    L. M. Reid; R. R. Ziemer; T. E. Lisle

    1996-01-01

    Environmental problems are never neatly defined. Instead, each is a tangle of interacting processes whose manifestation and interpretation are warped by the vagaries of time, weather, expectation, and economics. Each problem involves livelihoods, values, and numerous specialized disciplines. Nevertheless, federal agencies in the Pacific Northwest have been given the...

  5. Money, Policy Tangled in Wisconsin Labor Feud

    ERIC Educational Resources Information Center

    Cavanagh, Sean

    2011-01-01

    Gov. Scott Walker's sweeping proposal to scale back collective bargaining rights for most public employees in Wisconsin has sparked a rancorous standoff with teachers across the state--and fueled speculation about whether similar plans will gain traction in other parts of the country. But as massive demonstrations played out in Madison--an…

  6. Somewhere over the Verde Rainbow

    ERIC Educational Resources Information Center

    Ekart, Donna F.

    2008-01-01

    When the electronic resource management system (ERM) at Kansas State University Libraries suffered a horrible data loss, the "contract db" presented a challenge for the librarians responsible for electronic resources. It was a decent data repository, but it had no ability to manage the tangled process of licensing, acquiring, activating,…

  7. Untangling the Tangled Webs We Weave: A Team Approach to Cyberspace.

    ERIC Educational Resources Information Center

    Broidy, Ellen; And Others

    Working in a cooperative team environment across libraries and job classifications, librarians and support staff at the University of California at Irvine (UCI) have mounted several successful web projects, including two versions of the Libraries' home page, a virtual reference collection, and Science Library "ANTswer Machine." UCI's…

  8. More Needed for Coherent System

    ERIC Educational Resources Information Center

    Field, John

    2004-01-01

    From a learner's standpoint, Scotland's education system often looks less like a neat set of pathways than a tangled jungle. Since devolution, Scottish policymakers and the education community have set out to create a coherent and transparent set of opportunities for adult learners, of a quality to match Scotland's oft-praised unified system of…

  9. Moving toward a Coherent School Finance System

    ERIC Educational Resources Information Center

    Rose, Heather

    2013-01-01

    California's current school finance system is a tangled web of funding programs, restrictions, inequities and confusion. Building a stronger finance system to benefit from resources is an important step in strengthening California's K-12 education system and better meeting the needs of its students. Gov. Brown has recently proposed the Local…

  10. 7 CFR 29.3526 - Leaf scrap.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Leaf scrap. 29.3526 Section 29.3526 Agriculture... Type 95) § 29.3526 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [30 FR 9207, July 23, 1965...

  11. 7 CFR 29.3526 - Leaf scrap.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Leaf scrap. 29.3526 Section 29.3526 Agriculture... Type 95) § 29.3526 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [30 FR 9207, July 23, 1965...

  12. 7 CFR 29.3526 - Leaf scrap.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.3526 Section 29.3526 Agriculture... Type 95) § 29.3526 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [30 FR 9207, July 23, 1965...

  13. 7 CFR 29.3034 - Leaf scrap.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Leaf scrap. 29.3034 Section 29.3034 Agriculture... Leaf scrap. A by-product of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [24 FR 8771, Oct. 29, 1959. Redesignated at 49 FR...

  14. 7 CFR 29.3034 - Leaf scrap.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Leaf scrap. 29.3034 Section 29.3034 Agriculture... Leaf scrap. A by-product of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [24 FR 8771, Oct. 29, 1959. Redesignated at 49 FR...

  15. 7 CFR 29.3526 - Leaf scrap.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Leaf scrap. 29.3526 Section 29.3526 Agriculture... Type 95) § 29.3526 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [30 FR 9207, July 23, 1965...

  16. 7 CFR 29.3034 - Leaf scrap.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Leaf scrap. 29.3034 Section 29.3034 Agriculture... Leaf scrap. A by-product of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [24 FR 8771, Oct. 29, 1959. Redesignated at 49 FR...

  17. 7 CFR 29.3034 - Leaf scrap.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Leaf scrap. 29.3034 Section 29.3034 Agriculture... Leaf scrap. A by-product of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [24 FR 8771, Oct. 29, 1959. Redesignated at 49 FR...

  18. 7 CFR 29.3034 - Leaf scrap.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.3034 Section 29.3034 Agriculture... Leaf scrap. A by-product of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [24 FR 8771, Oct. 29, 1959. Redesignated at 49 FR...

  19. 7 CFR 29.3526 - Leaf scrap.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Leaf scrap. 29.3526 Section 29.3526 Agriculture... Type 95) § 29.3526 Leaf scrap. A byproduct of unstemmed tobacco Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or broken leaves. [30 FR 9207, July 23, 1965...

  20. Parallel logic gates in synthetic gene networks induced by non-Gaussian noise.

    PubMed

    Xu, Yong; Jin, Xiaoqin; Zhang, Huiqing

    2013-11-01

    The recent idea of logical stochastic resonance is verified in synthetic gene networks induced by non-Gaussian noise. We realize the switching between two kinds of logic gates under optimal moderate noise intensity by varying two different tunable parameters in a single gene network. Furthermore, in order to obtain more logic operations, thus providing additional information processing capacity, we obtain in a two-dimensional toggle switch model two complementary logic gates and realize the transformation between two logic gates via the methods of changing different parameters. These simulated results contribute to improve the computational power and functionality of the networks.

  1. Toggle switch from optical bistability to multistability via an elliptically polarized field

    NASA Astrophysics Data System (ADS)

    Yan, Xiang-An; Ren, Bo-Quan; Wang, Li-Qiang; Liu, Yao-Wu; Yu, Hua-Wa

    2017-06-01

    In this paper, we propose a scheme for manipulating the behavior of optical bistability (OB) and optical multistability (OM) in an N-type four-level atomic system. In the scheme, quantum interference is optimized by the left-handed and the right-handed fields of an elliptically polarized field (EPF). The threshold and the hysteresis cycle shape of OB and OM can be controlled by modulating the intensity of the EPF. Especially, the transition from OB to OM or vice versa can also be easily realized by proper tuning the phase difference between the left-handed and right-handed polarized fields under the optimal intensity of the EPF.

  2. When Education Research Matters. Education Outlook, No. 1

    ERIC Educational Resources Information Center

    Hess, Frederick M.

    2008-01-01

    The tangled relationship between education research and policy has received little serious scrutiny, even as paeans to "scientifically based research" and "evidence-based practice" have become a staple of education policymaking in recent years. For all the attention devoted to the five-year-old Institute of Education Sciences, to No Child Left…

  3. Facebook-Driven Newark Overhaul Lurches Forward

    ERIC Educational Resources Information Center

    Gewertz, Catherine

    2010-01-01

    What began as a swashbuckling move by the mayor of Newark, New Jersey, the state's governor, and a newly minted billionaire to reshape the beleaguered Newark school system has turned into a tangle of blowback and counterpunches as skeptics contend the plan would violate state law. At issue is the power-sharing arrangement proposed by the three…

  4. Length Dependent Foam-Like Mechanical Response of Axially Indented Vertically Oriented Carbon Nanotube Arrays

    DTIC Science & Technology

    2011-01-01

    Sands T, Xu X, Fisher T. Dendrimer -assisted controlled growth of carbon nanotubes for enhanced thermal interface conductance. Nanotechnology 2007;18...surfaces. Rev Sci Instrum 2006;77(9):095105-1–3. [11] Allaoui A, Hoa S, Evesque P, Bai J. Electronic transport in carbon nanotube tangles under compression

  5. Citizenship, Nationalism, Human Rights and Democracy: A Tangling of Terms in the Kuwaiti Curriculum

    ERIC Educational Resources Information Center

    Al-Nakib, Rania

    2011-01-01

    Background: Citizenship, nationalism, human rights and democracy are four terms and concepts that are inextricably linked. In Kuwait, the status of citizen is based on nationality, gender and age, with women, children, naturalised citizens, expatriates and "bidoon" (stateless people) denied many freedoms, rights and services. Citizenship…

  6. Tangled up in Blue: Boosting Mental Health Services at Community Colleges

    ERIC Educational Resources Information Center

    Finkel, Ed

    2016-01-01

    In a recent survey of 4,000 community college students, half reported experiencing a mental health condition. American College Counseling Association's (ACCA) fifth annual survey of personal and mental health counseling at community colleges provides some data from 159 professionals at two-year colleges in 41 states and Puerto Rico. Among the…

  7. Tangled Webs: Tracing the Connections between Genes and Cognition

    ERIC Educational Resources Information Center

    Fisher, Simon E.

    2006-01-01

    The rise of molecular genetics is having a pervasive influence in a wide variety of fields, including research into neurodevelopmental disorders like dyslexia, speech and language impairments, and autism. There are many studies underway which are attempting to determine the roles of genetic factors in the aetiology of these disorders. Beyond the…

  8. Sketches in Democracy: Notes from an Urban Classroom

    ERIC Educational Resources Information Center

    DeLorenzo, Lisa

    2012-01-01

    "Sketches of Democracy" is a captivating book that chronicles the first year in the life of a new urban high school. Based on journal entries and educational literature, this book traces the author's challenging journey toward creating a democratic community of learners within a tangle of socio-economic and political issues. An experienced public…

  9. "A Complicated Tangle of Circumstances"

    ERIC Educational Resources Information Center

    Miller, Carole; Saxton, Juliana

    2009-01-01

    The post-modern curriculum, drawing on chaos and complexity theory, recognises the realities of a world in flux and posits that the teacher and the class are always teetering "in the midst" of chaos, "not linked by chains of causality but [by] layers of meaning, recursive dynamics, non-linear effects and chance" (Osberg 2008,…

  10. Credit Squeeze Exposes Weaknesses in Investments

    ERIC Educational Resources Information Center

    Blumenstyk, Goldie; Field, Kelly

    2008-01-01

    This article reports that the credit crisis tying global financing systems into knots has left hundreds of colleges scrambling for cash to pay their bills and to cover the spiking interest on their debts. While it is still unclear to what extent the federal government's new $700-billion bailout package will help unwind the credit tangle, the…

  11. The Tangled Web: Delinquency, Deception, and Parental Attachment

    ERIC Educational Resources Information Center

    Warr, Mark

    2007-01-01

    Delinquent youth display weaker attachment to their parents than do other youth, but the reasons for this remain unclear. One explanation is that delinquent youth poison their relations with parents by lying to them about their friends, behavior, whereabouts, and more. Analysis of data from the National Longitudinal Study of Adolescent Health…

  12. The Principal's Quick-Reference Guide to School Law: Reducing Liability, Litigation, and Other Potential Legal Tangles.

    ERIC Educational Resources Information Center

    Dunklee, Dennis R.; Shoop, Robert J.

    This book is designed to inform school administrators regarding school law. As a resource, it provides suggested, easy-to-understand guidelines for the avoidance of litigation. Subjects include preventive law and risk management; constitutional and statutory foundations of staff selection, contracting, and evaluation; negligent hiring, defamation,…

  13. 7 CFR 29.2529 - Leaf scrap.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Leaf scrap. 29.2529 Section 29.2529 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2529 Leaf scrap. A byproduct of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or...

  14. 7 CFR 29.2529 - Leaf scrap.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Leaf scrap. 29.2529 Section 29.2529 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2529 Leaf scrap. A byproduct of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or...

  15. 7 CFR 29.2529 - Leaf scrap.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Leaf scrap. 29.2529 Section 29.2529 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2529 Leaf scrap. A byproduct of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or...

  16. 7 CFR 29.2529 - Leaf scrap.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Leaf scrap. 29.2529 Section 29.2529 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2529 Leaf scrap. A byproduct of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or...

  17. 7 CFR 29.2529 - Leaf scrap.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Leaf scrap. 29.2529 Section 29.2529 Agriculture...-Cured Tobacco (u.s. Types 22, 23, and Foreign Type 96) § 29.2529 Leaf scrap. A byproduct of unstemmed tobacco. Leaf scrap results from handling unstemmed tobacco and consists of loose and tangled whole or...

  18. Hard Labour and Punitive Welfare: The Unemployed Body at Work in Participatory Performance

    ERIC Educational Resources Information Center

    Bartley, Sarah

    2017-01-01

    This article addresses the performance of labour in participatory arts projects and considers the implications of such activity on perceptions of the unemployed in the UK. Utilising a combination of biopolitical and necropolitical understandings of governance and drawing on two examples of theatre practice, Tangled Feet's "One Million"…

  19. Dietary supplementation with non-prey food enhances fitness of a predatory arthropod

    USDA-ARS?s Scientific Manuscript database

    Uncertainties exist about the value of non-prey food for natural enemies that are commonly food limited, and the dietary conditions where non-prey foods are beneficial for carnivorous species. We examined the nutritional role of a non-prey food using a ground dwelling, tangle web-building spider tha...

  20. Fluorescent rhodanine-3-acetic acids visualize neurofibrillary tangles in Alzheimer's disease brains.

    PubMed

    Anumala, Upendra Rao; Gu, Jiamin; Lo Monte, Fabio; Kramer, Thomas; Heyny-von Haußen, Roland; Hölzer, Jana; Goetschy-Meyer, Valerie; Schön, Christian; Mall, Gerhard; Hilger, Ingrid; Czech, Christian; Herms, Jochen; Schmidt, Boris

    2013-09-01

    There is a high demand for the development of an imaging agent for neurofibrillary tangles (NFTs) detection in Alzheimer's diagnosis. In the present study, a series of rhodanine-3-acetic acids was synthesized and evaluated for fluorescence imaging of NFTs in brain tissues of AD patients. Five out of seven probes have shown excellent binding affinity to NFTs over amyloid plaques in the Thiazine red R displacement assay. However, the selectivity in this in vitro assay is not confirmed by the histopathological evaluation, which indicates significant differences in the binding sites in the assays. Probe 6 showed binding affinity (IC50=19nM) to tau aggregates which is the highest among this series. Probes 2, 3, 4 and 5 display IC50 values of lower than 100nM to tau aggregates to displace Thiazine red R. Evaluation of the cytotoxicity of these five probes with human liver carcinoma cells revealed that these compounds excert negligible cytotoxicity. The in vivo studies with zebrafish embryos confirmed negligible cytotoxicity at 24 and 72h post fertilization. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Is synaptic loss a unique hallmark of Alzheimer's disease?

    PubMed Central

    Scheff, Stephen W.; Neltner, Janna H.; Nelson, Peter T.

    2014-01-01

    Synapses may represent a key nidus for dementia including Alzheimer's disease (AD) pathogenesis. Here we review published studies and present new ideas related to the question of the specificity of synapse loss in AD. Currently, AD is defined by the regional presence of neuritic plaques and neurofibrillary tangles in the brain. The severity of involvement by those pathological hallmarks tends to correlate both with antemortem cognitive status, and also with synapse loss in multiple brain areas. Recent studies from large autopsy series have led to a new standard of excellence with regard to clinical–pathological correlation and to improved comprehension of the numerous brain diseases of the elderly. These studies have provided evidence that it is the rule rather than the exception for brains of aged individuals to demonstrate pathologies (often multiple) other than AD plaques and tangles. For many of these comorbid pathologies, the extent of synapse loss is imperfectly understood but could be substantial. These findings indicate that synapse loss is probably not a hallmark specific to AD but rather a change common to many diseases associated with dementia. PMID:24412275

  2. Caspase-6 activity in the CA1 region of the hippocampus induces age-dependent memory impairment

    PubMed Central

    LeBlanc, A C; Ramcharitar, J; Afonso, V; Hamel, E; Bennett, D A; Pakavathkumar, P; Albrecht, S

    2014-01-01

    Active Caspase-6 is abundant in the neuropil threads, neuritic plaques and neurofibrillary tangles of Alzheimer disease brains. However, its contribution to the pathophysiology of Alzheimer disease is unclear. Here, we show that higher levels of Caspase-6 activity in the CA1 region of aged human hippocampi correlate with lower cognitive performance. To determine whether Caspase-6 activity, in the absence of plaques and tangles, is sufficient to cause memory deficits, we generated a transgenic knock-in mouse that expresses a self-activated form of human Caspase-6 in the CA1. This Caspase-6 mouse develops age-dependent spatial and episodic memory impairment. Caspase-6 induces neuronal degeneration and inflammation. We conclude that Caspase-6 activation in mouse CA1 neurons is sufficient to induce neuronal degeneration and age-dependent memory impairment. These results indicate that Caspase-6 activity in CA1 could be responsible for the lower cognitive performance of aged humans. Consequently, preventing or inhibiting Caspase-6 activity in the aged may provide an efficient novel therapeutic approach against Alzheimer disease. PMID:24413155

  3. Exact zeros of entanglement for arbitrary rank-two mixtures derived from a geometric view of the zero polytope

    NASA Astrophysics Data System (ADS)

    Osterloh, Andreas

    2016-12-01

    Here I present a method for how intersections of a certain density matrix of rank 2 with the zero polytope can be calculated exactly. This is a purely geometrical procedure which thereby is applicable to obtaining the zeros of SL- and SU-invariant entanglement measures of arbitrary polynomial degree. I explain this method in detail for a recently unsolved problem. In particular, I show how a three-dimensional view, namely, in terms of the Bloch-sphere analogy, solves this problem immediately. To this end, I determine the zero polytope of the three-tangle, which is an exact result up to computer accuracy, and calculate upper bounds to its convex roof which are below the linearized upper bound. The zeros of the three-tangle (in this case) induced by the zero polytope (zero simplex) are exact values. I apply this procedure to a superposition of the four-qubit Greenberger-Horne-Zeilinger and W state. It can, however, be applied to every case one has under consideration, including an arbitrary polynomial convex-roof measure of entanglement and for arbitrary local dimension.

  4. Dual action of memantine in Alzheimer disease: a hypothesis.

    PubMed

    Wu, Tzong-Yuan; Chen, Chih-Ping

    2009-09-01

    In this study, we proposed a hypothesis to explain the mechanisms of memantine action in treating Alzheimer disease (AD). Memantine may reduce the expression of amyloid precursor protein and tau protein, as well as acting as an antagonist of N-methyl-D-aspartate receptors in the brain. Two neuropathologic characteristics of AD are neuritic plaques and neurofibrillary tangles. The major molecular components of the plaques and tangles are amyloid-beta peptide and tau, respectively. Drugs able to reduce the expression of amyloid-beta and tau protein provide potential pharmaceutical treatments for AD. We found that memantine inhibited internal ribosome entry site-mediated translation initiation in COS-1 cells. This suggests that the memantine may not only inhibit neuronal excitotoxicity, but also act as an inhibitor of the internal ribosome entry site, to block the expression of amyloid precursor protein and tau in neurons. Memantine may function not only as an antagonist of N-methyl-D-aspartate receptors, but also as an inhibitor of the internal ribosome entry site to block the expression of amyloid precursor protein and tau, and so ameliorate the symptoms of AD.

  5. KSC00padig013

    NASA Image and Video Library

    2000-04-22

    KENNEDY SPACE CENTER, FLA. -- At left, a manipulator arm on a one-man submarine demonstrates its ability to cut tangled parachute riser lines and place a Diver Operator Plug (top right) inside a mock solid rocket booster nozzle (center). Known as DeepWorker 2000, the sub is being tested on its ability to duplicate the sometimes hazardous job United Space Alliance (USA) divers perform to recover the expended boosters in the ocean after a launch. The boosters splash down in an impact area about 140 miles east of Jacksonville and after recovery are towed back to KSC for refurbishment by the specially rigged recovery ships. DeepWorker 2000 will be used in a demonstration during retrieval operations after the upcoming STS-101 launch. The submarine pilot will demonstrate capabilities to cut tangled parachute riser lines using a manipulator arm and attach the DOP to extract water and provide flotation for the booster. DeepWorker 2000 was built by Nuytco Research Ltd., North Vancouver, British Columbia. It is 8.25 feet long, 5.75 feet high, and weighs 3,800 pounds. USA is a prime contractor to NASA for the Space Shuttle program

  6. KSC-00padig013

    NASA Image and Video Library

    2000-04-22

    KENNEDY SPACE CENTER, FLA. -- At left, a manipulator arm on a one-man submarine demonstrates its ability to cut tangled parachute riser lines and place a Diver Operator Plug (top right) inside a mock solid rocket booster nozzle (center). Known as DeepWorker 2000, the sub is being tested on its ability to duplicate the sometimes hazardous job United Space Alliance (USA) divers perform to recover the expended boosters in the ocean after a launch. The boosters splash down in an impact area about 140 miles east of Jacksonville and after recovery are towed back to KSC for refurbishment by the specially rigged recovery ships. DeepWorker 2000 will be used in a demonstration during retrieval operations after the upcoming STS-101 launch. The submarine pilot will demonstrate capabilities to cut tangled parachute riser lines using a manipulator arm and attach the DOP to extract water and provide flotation for the booster. DeepWorker 2000 was built by Nuytco Research Ltd., North Vancouver, British Columbia. It is 8.25 feet long, 5.75 feet high, and weighs 3,800 pounds. USA is a prime contractor to NASA for the Space Shuttle program

  7. The Structure of Coronal Loops

    NASA Technical Reports Server (NTRS)

    Antiochos, Spiro K.

    2009-01-01

    It is widely believed that the simple coronal loops observed by XUV imagers, such as EIT, TRACE, or XRT, actually have a complex internal structure consisting of many (perhaps hundreds) of unresolved, interwoven "strands". According to the nanoflare model, photospheric motions tangle the strands, causing them to reconnect and release the energy required to produce the observed loop plasma. Although the strands, themselves, are unresolved by present-generation imagers, there is compelling evidence for their existence and for the nanoflare model from analysis of loop intensities and temporal evolution. A problem with this scenario is that, although reconnection can eliminate some of the strand tangles, it cannot destroy helicity, which should eventually build up to observable scales. we consider, therefore, the injection and evolution of helicity by the nanoflare process and its implications for the observed structure of loops and the large-scale corona. we argue that helicity does survive and build up to observable levels, but on spatial and temporal scales larger than those of coronal loops. we discuss the implications of these results for coronal loops and the corona, in general .

  8. Microinfarcts are common and strongly related to dementia in the oldest-old: The 90+ study.

    PubMed

    Corrada, María M; Sonnen, Joshua A; Kim, Ronald C; Kawas, Claudia H

    2016-08-01

    We estimated the prevalence of microinfarcts and their association with dementia in a cohort of oldest-old participants. Participants were from The 90+ Study, a population-based study of people 90 years and older. Dementia diagnoses were assigned postmortem during a consensus conference. Microinfarcts were evaluated in six brain regions. At death, the 213 participants were on average 97 years old, 69% were women, and 52% had dementia. Of the participants, 51% had microinfarcts and 17% had 3+ microinfarcts. The odds ratio (OR) for dementia was similar for 3+ microinfarcts (OR = 4.75, P < .01) and tangle stage V-VI (OR = 4.70, P < .001). Only microinfarcts in cortical regions (other than occipital) were associated to dementia. In this oldest-old cohort, microinfarcts are common and contribute independently and similarly in magnitude to dementia as tangles. As risk factors for microinfarcts and other dementing pathologies are likely to differ, identifying these factors is crucial to developing prevention strategies for dementia in the oldest-old. Copyright © 2016 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.

  9. Dissociation and Re-Aggregation of Multicell-Ensheathed Fragments Responsible for Rapid Production of Massive Clumps of Leptothrix Sheaths

    PubMed Central

    Kunoh, Tatsuki; Nagaoka, Noriyuki; McFarlane, Ian R.; Tamura, Katsunori; El-Naggar, Mohamed Y.; Kunoh, Hitoshi; Takada, Jun

    2016-01-01

    Species of the Fe/Mn-oxidizing bacteria Leptothrix produce tremendous amounts of microtubular, Fe/Mn-encrusted sheaths within a few days in outwells of groundwater that can rapidly clog water systems. To understand this mode of rapid sheath production and define the timescales involved, behaviors of sheath-forming Leptothrix sp. strain OUMS1 were examined using time-lapse video at the initial stage of sheath formation. OUMS1 formed clumps of tangled sheaths. Electron microscopy confirmed the presence of a thin layer of bacterial exopolymer fibrils around catenulate cells (corresponding to the immature sheath). In time-lapse videos, numerous sheath filaments that extended from the periphery of sheath clumps repeatedly fragmented at the apex of the same fragment, the fragments then aggregated and again elongated, eventually forming a large sheath clump comprising tangled sheaths within two days. In this study, we found that fast microscopic fragmentation, dissociation, re-aggregation and re-elongation events are the basis of the rapid, massive production of Leptothrix sheaths typically observed at macroscopic scales. PMID:27490579

  10. Vortex arrays and ciliary tangles underlie the feeding-swimming trade-off in starfish larvae

    NASA Astrophysics Data System (ADS)

    Gilpin, William; Prakash, Vivek N.; Prakash, Manu

    2017-04-01

    Many marine invertebrates have larval stages covered in linear arrays of beating cilia, which propel the animal while simultaneously entraining planktonic prey. These bands are strongly conserved across taxa spanning four major superphyla, and they are responsible for the unusual morphologies of many invertebrate larvae. However, few studies have investigated their underlying hydrodynamics. Here, we study the ciliary bands of starfish larvae, and discover a beautiful pattern of slowly evolving vortices that surrounds the swimming animals. Closer inspection of the bands reveals unusual ciliary `tangles' analogous to topological defects that break up and re-form as the animal adjusts its swimming stroke. Quantitative experiments and modelling demonstrate that these vortices create a physical trade-off between feeding and swimming in heterogeneous environments, which manifests as distinct flow patterns or `eigenstrokes' representing each behaviour--potentially implicating neuronal control of cilia. This quantitative interplay between larval form and hydrodynamic function may generalize to other invertebrates with ciliary bands, and illustrates the potential effects of active boundary conditions in other biological and synthetic systems.

  11. Kelp Gulls (Larus dominicanus) killed and injured by discarded monofilament lines at a marine recreational fishery in northern Patagonia.

    PubMed

    Yorio, Pablo; Marinao, Cristian; Suárez, Nicolás

    2014-08-15

    Among marine debris, monofilament fishing lines often result in negative impacts on marine organisms. We characterized marine debris and incidence of lost and discarded monofilament lines along beaches used by recreational fishers, and report the impact of lines on Kelp Gulls (Larus dominicanus) at the Bahía San Blas protected area, site of one of the main shore-based recreational fisheries of the southwestern Atlantic. Over 55% of the marine debris recorded originated from recreational fishing activities. Balls of tangled monofilament lines were found at a rate of 40.5 items per km. A total of 27 adult Kelp Gulls were found entangled with monofilament. All individuals were tangled to vegetation within colony boundaries. Four of the gulls had a monofilament line protruding from the bill, showing that they may be also killed when trying to obtain bait. Our results indicate that lost or discarded monofilament lines in the Bahía San Blas recreational fishing area result in undesired impacts on coastal wildlife. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Non-Alzheimer's contributions to dementia and cognitive resilience in The 90+ Study.

    PubMed

    Robinson, John L; Corrada, Maria M; Kovacs, Gabor G; Dominique, Myrna; Caswell, Carrie; Xie, Sharon X; Lee, Virginia M-Y; Kawas, Claudia H; Trojanowski, John Q

    2018-06-18

    The diagnosis of Alzheimer's disease (AD) in the oldest-old is complicated by the increasing prevalence of age-related neurofibrillary tangles, plaques and non-AD pathologies such as cerebrovascular disease (CVD), hippocampal sclerosis (HS), aging-related tau astrogliopathy (ARTAG), as well as TDP-43 and Lewy pathology. The contribution of these non-AD pathologies to dementia and cognitive resilience is unclear. We assessed the level of AD neuropathologic change (ADNPC) and non-AD pathology in 185 participants enrolled in The 90+ Study with available cognitive assessments and brain tissue. Logistic regression models-adjusting for age, sex and education-determined the association between each pathology and dementia or between subgroups. 53% had dementia, primarily AD or mixed AD; 23% had cognitive impairment without dementia (CIND); 23% were not impaired. Both AD and non-AD pathology was prevalent. 100% had tangles, 81% had plaques, and both tangles and plaques associated with dementia. ARTAG distributed across limbic (70%), brainstem (39%) and cortical regions (24%). 49% had possible CVD and 26% had definite CVD, while HS was noted in 15%. Cortical ARTAG, CVD and HS were each associated with dementia, but limbic and brainstem ARTAGs were not. TDP-43 and Lewy pathologies were found in 36 and 17% and both associated with dementia. No pathology distinguished CIND and the not impaired. By NIA-AA criteria and dementia status, the cohort was subdivided into four groups: those with minimal ADNPC included the not dementia (ND) and Not AD dementia groups; and those with significant ADNPC included the Resilient without dementia and AD dementia groups. Compared to the ND group, the Not AD dementia group had more HS, cortical ARTAG, TDP-43, and Lewy pathology. Compared to the AD dementia group, the Resilient group had less CVD, no HS and less cortical ARTAG, TDP-43 and Lewy pathology. Our findings imply that reductions in non-AD pathologies including CVD contribute to cognitive resilience in the oldest-old.

  13. Modifiable Risk Factors and Brain PET Measures of Amyloid and Tau in Non-Demented Adults with Memory Complaints

    PubMed Central

    Merrill, David A.; Siddarth, Prabha; Raji, Cyrus A.; Emerson, Natacha D.; Rueda, Florangel; Ercoli, Linda M.; Miller, Karen J.; Lavretsky, Helen; Harris, Laurel M.; Burggren, Alison C.; Bookheimer, Susan Y.; Barrio, Jorge R.; Small, Gary W.

    2016-01-01

    Objective Exercise and diet impact body composition, but their age-related brain effects are unclear at the molecular imaging level. To address these issues, we determined whether body mass index (BMI), physical activity, and diet relate to brain positron emission tomography (PET) of amyloid plaques and tau tangles using 2-(1-(6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl)ethylidene)malononitrile (FDDNP). Methods Volunteers (n = 44, mean age = 62.6 ± 10.7 years) with subjective memory impairment (n = 24) or mild cognitive impairment (MCI; n = 20) were recruited by soliciting for memory complaints. Levels of physical activity and extent of following a Mediterranean-type diet were self-reported. FDDNP-PET scans assessed plaque/tangle binding in Alzheimer’s disease (AD)-associated regions (frontal, parietal, medial and lateral temporal, posterior cingulate). Mixed models controlling for known covariates examined BMI, physical activity, and diet in relation to FDDNP-PET. Results MCI subjects with above normal BMI (>25) had higher FDDNP-PET binding compared to those with normal BMI (1.11(.03) vs 1.08(.03), ES=1.04, t(35)=3.3, p=.002). Greater physical activity was associated with lower FDDNP-PET binding in MCI subjects (1.07(.03) vs 1.11(.03), ES=1.13, t(35) =−3.1, p=.004) but not in subjects with subjective memory impairment (1.07 (.03) vs 1.07(.03), ES=.02, t(35)=−0.1, p=.9). Healthier diet related to lower FDDNP-PET binding, regardless of cognitive status (1.07(.03) vs 1.09(.02), ES=0.72, t(35)=−2.1, p = .04). Conclusion and Relevance These preliminary findings are consistent with a relationship between risk modifiers and brain plaque/tangle deposition in non-demented individuals and supports maintenance of normal body weight, regular physical activity, and healthy diet adherence to protect the brain during aging. PMID:27421618

  14. Quench dynamics of the three-dimensional U(1) complex field theory: Geometric and scaling characterizations of the vortex tangle.

    PubMed

    Kobayashi, Michikazu; Cugliandolo, Leticia F

    2016-12-01

    We present a detailed study of the equilibrium properties and stochastic dynamic evolution of the U(1)-invariant relativistic complex field theory in three dimensions. This model has been used to describe, in various limits, properties of relativistic bosons at finite chemical potential, type II superconductors, magnetic materials, and aspects of cosmology. We characterize the thermodynamic second-order phase transition in different ways. We study the equilibrium vortex configurations and their statistical and geometrical properties in equilibrium at all temperatures. We show that at very high temperature the statistics of the filaments is the one of fully packed loop models. We identify the temperature, within the ordered phase, at which the number density of vortex lengths falls off algebraically and we associate it to a geometric percolation transition that we characterize in various ways. We measure the fractal properties of the vortex tangle at this threshold. Next, we perform infinite rate quenches from equilibrium in the disordered phase, across the thermodynamic critical point, and deep into the ordered phase. We show that three time regimes can be distinguished: a first approach toward a state that, within numerical accuracy, shares many features with the one at the percolation threshold; a later coarsening process that does not alter, at sufficiently low temperature, the fractal properties of the long vortex loops; and a final approach to equilibrium. These features are independent of the reconnection rule used to build the vortex lines. In each of these regimes we identify the various length scales of the vortices in the system. We also study the scaling properties of the ordering process and the progressive annihilation of topological defects and we prove that the time-dependence of the time-evolving vortex tangle can be described within the dynamic scaling framework.

  15. [Lessons from Guam ALS/PDC study].

    PubMed

    Asao, Hirano

    2007-11-01

    An extraordinarily high incidence of amyotrophic lateral sclerosis (ALS) and parkinsonism-dementia complex (PDC) affecting the native population was discovered on the island of Guam a half century ago. Guam ALS is identical to classic ALS clinically and pathologically while PDC is marked by progressive parkinsonism and dementia. The unusual histological finding in these fetal neurodegenerative diseases is the presence of numerous neurofibrillary tangles in a selective topographic distribution unassociated with senile plaques. There have been remarkable advances in field of age-associated neurodegenerative disease after our initial study of Guam cases. Four noteworthy topics are presented in this communication. 1) Clinically, the coexistence of parkinsonism and dementia was frequently recognized in Parkinson disease and Alzheimer disease. Some other new disease entities characterized by coexistence of parkinsonism and dementia have been reported. These include progressive supranuclear palsy, frontotemporal dementia and parkinsonism linked to chromosome 17. 2) Neuropathologically, abundant neurofibrillary tangles unassociated with senile plaques were demonstrated in many diseases such as aftermath of boxing and tangle-only dementia. Furthermore, tau-positive structures were recognized not only in neurons but in glial cells in certain diseases. Tauopathy is one of the current hot research subjects. 3) Familial aggregation of Guam ALS patients provoked investigation of familial ALS elsewhere. Familial motor neuron disease with SOD1 mutation is the target of worldwide intense investigation at the present time. SOD1 gene mutation is, however, not found in Guam ALS. 4) The most striking findings of the Guam study is the gradual decline in the incidence of ALS on Guam during a quarter century and virtual disappearance of new patients. This may be linked to a remarkable change in environment and life style of the Chamorro population. The etiology of ALS is still unknown and no new treatment is available. Guam ALS/PDC is certainly one of the most mysterious riddles among age-associated neurodegenerative diseases during the last half a century.

  16. A Qualitative Study of Confusing Experiences among Japanese Adult Patients with Type 1 Diabetes

    PubMed Central

    Nishio, Ikuko; Chujo, Masami; Kataoka, Hideyuki

    2016-01-01

    Background In this study, we investigated the powerlessness of patients with type 1 diabetes (T1D), and described the structure of powerlessness that these individuals experienced. In order for patients to recover from this state, we recommend that they take steps to regain their power. Methods Fifteen Japanese adults with T1D participated in this study. Data were collected from all subjects between July 2013 and March 2014 via in-depth semi-structured interviews. Qualitative data analysis was conducted according to a grounded theory approach. Finally, the core category was identified, which allowed us to build a new powerlessness structure for T1D. Results The results suggested a core category, ‘Wandering a tangled path,’ comprising four categories, eight subcategories, and twenty-six concepts. These four categories were as follows: ‘being burdened by T1D,’ ‘suffering from insulin-related troubles,’ ‘being unable to cope with difficulties in self-management,’ and ‘facing social prejudice.’ In the state of powerlessness, negative emotional experiences snowballed, with patients feeling more and more depressed until they ultimately reached ‘rock bottom.’ Conclusion We found that as negative emotional experiences related to powerlessness increased, negative feelings intensified until the patients reached rock bottom. Powerlessness is like ‘wandering a tangled path,’ a state in which T1D patients struggle to cope with reality on their own when faced with both internal and external events. ‘Wandering a tangled path’ is at the core of powerlessness. A primary characteristic of the structure of powerlessness is suffering from confusing experiences. To help patients cope with T1D without being crushed by powerlessness, nurses must pay attention to signs of powerlessness. Powerlessness is not just an emotional state, but a combination of feelings, perceptions, and thoughts; therefore, it is important to comprehensively understand patients’ narratives. PMID:27046954

  17. Tackling in Youth Football.

    PubMed

    2015-11-01

    American football remains one of the most popular sports for young athletes. The injuries sustained during football, especially those to the head and neck, have been a topic of intense interest recently in both the public media and medical literature. The recognition of these injuries and the potential for long-term sequelae have led some physicians to call for a reduction in the number of contact practices, a postponement of tackling until a certain age, and even a ban on high school football. This statement reviews the literature regarding injuries in football, particularly those of the head and neck, the relationship between tackling and football-related injuries, and the potential effects of limiting or delaying tackling on injury risk. Copyright © 2015 by the American Academy of Pediatrics.

  18. Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study.

    PubMed

    Burger, Nicholas; Lambert, Mike I; Viljoen, Wayne; Brown, James C; Readhead, Clint; Hendricks, Sharief

    2014-08-12

    The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of tackle-related injuries in South African youth rugby union players representing their provinces at national tournaments. Observational cohort study. Four South African Youth Week tournaments (under-13 Craven Week, under-16 Grant Khomo Week, under-18 Academy Week, under-18 Craven Week). Injury data were collected from 3652 youth rugby union players (population at risk) in 2011 and 2012. Tackle-related injury severity ('time-loss' and 'medical attention'), type and location, injury rate per 1000 h (including 95% CIs). Injury rate ratios (IRR) were calculated and modelled using a Poisson regression. A χ(2) analysis was used to detect linear trends between injuries and increasing match quarters. The 2012 under-13 Craven Week had a significantly greater 'time-loss' injury rate when compared with the 2012 under-18 Academy Week (IRR=4.43; 95% CI 2.13 to 9.21, p<0.05) and under-18 Craven Week (IRR=3.52; 95% CI 1.54 to 8.00, p<0.05). The Poisson regression also revealed a higher probability of 'overall' ('time-loss' and 'medical attention' combined) and 'time-loss' tackle-related injuries occurring at the under-13 Craven Week. The proportion of 'overall' and 'time-loss' injuries increased significantly with each quarter of the match when all four tournaments were combined (p<0.05). There was a difference in the tackle-related injury rate between the under-13 tournament and the two under-18 tournaments, and the tackle-related injury rate was higher in the final quarter of matches. Ongoing injury surveillance is required to better interpret these findings. Injury prevention strategies targeting the tackle may only be effective once the rate and nature of injuries have been accurately determined. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  19. Tackle-related injury rates and nature of injuries in South African Youth Week tournament rugby union players (under-13 to under-18): an observational cohort study

    PubMed Central

    Burger, Nicholas; Lambert, Mike I; Viljoen, Wayne; Brown, James C; Readhead, Clint; Hendricks, Sharief

    2014-01-01

    Objectives The tackle situation is most often associated with the high injury rates in rugby union. Tackle injury epidemiology in rugby union has previously been focused on senior cohorts but less is known about younger cohorts. The aim of this study was to report on the nature and rates of tackle-related injuries in South African youth rugby union players representing their provinces at national tournaments. Design Observational cohort study. Setting Four South African Youth Week tournaments (under-13 Craven Week, under-16 Grant Khomo Week, under-18 Academy Week, under-18 Craven Week). Participants Injury data were collected from 3652 youth rugby union players (population at risk) in 2011 and 2012. Outcome measures Tackle-related injury severity (‘time-loss’ and ‘medical attention’), type and location, injury rate per 1000 h (including 95% CIs). Injury rate ratios (IRR) were calculated and modelled using a Poisson regression. A χ2 analysis was used to detect linear trends between injuries and increasing match quarters. Results The 2012 under-13 Craven Week had a significantly greater ‘time-loss’ injury rate when compared with the 2012 under-18 Academy Week (IRR=4.43; 95% CI 2.13 to 9.21, p<0.05) and under-18 Craven Week (IRR=3.52; 95% CI 1.54 to 8.00, p<0.05). The Poisson regression also revealed a higher probability of ‘overall’ (‘time-loss’ and ‘medical attention’ combined) and ‘time-loss’ tackle-related injuries occurring at the under-13 Craven Week. The proportion of ‘overall’ and ‘time-loss’ injuries increased significantly with each quarter of the match when all four tournaments were combined (p<0.05). Conclusions There was a difference in the tackle-related injury rate between the under-13 tournament and the two under-18 tournaments, and the tackle-related injury rate was higher in the final quarter of matches. Ongoing injury surveillance is required to better interpret these findings. Injury prevention strategies targeting the tackle may only be effective once the rate and nature of injuries have been accurately determined. PMID:25116454

  20. Subjective Well-Being in Obese Individuals: The Multiple Roles of Exercise

    ERIC Educational Resources Information Center

    Berger, Bonnie G.

    2004-01-01

    This paper focuses on the tangled web of obesity and exercise as it relates to subjective well-being. Many overweight individuals have low levels of subjective well-being as a reflection of "anti-fat" biases and sociocultural considerations. Since exercise helps balance the energy intake-output equation and is associated with mood benefits,…

  1. "It Takes at Least Two to Tangle"

    ERIC Educational Resources Information Center

    Walker, Janice M.

    2010-01-01

    Despite past lessons, book-banning continues to exist at all levels within our democratic society. This case presents a realistic scenario when the school district, facing a book challenge by a concerned parent, responds by removing the book from the library. On the basis of a true story, the study features a parent of an elementary child…

  2. One Stroke at a Time

    ERIC Educational Resources Information Center

    Hollibaugh, Molly

    2012-01-01

    At first glance, a Zentangle creation can seem intricate and complicated. But, when you learn how it is done, you realize how simple it is. Zentangles are patterns, or "tangles," that have been reduced to a simple sequence of elemental strokes. When you learn to focus on each stroke you find yourself capable of things that you may have once…

  3. The Other Memex: The Tangled Career of Vannevar Bush's Information Machine, the Rapid Selector.

    ERIC Educational Resources Information Center

    Burke, Colin

    1992-01-01

    Presents an historical overview of Vannevar Bush's efforts to develop a machine for free-form indexing and computerized information retrieval. Descriptions of the Memex concept and two related machines--the Rapid Selector and the Comparator--are provided; and the shift in emphasis to a device for business or cryptanalytic purposes is discussed.…

  4. The Reformulation of National Identity in the New Taiwanese Citizenship Curriculum through the Lens of Curriculum Reformers

    ERIC Educational Resources Information Center

    Hung, Cheng-Yu

    2017-01-01

    The national curriculum reformers, regarded as members of the social elites and intellectuals, projected their vision of identity onto the curriculum which they constructed and influenced the next generation's national consciousness. In the tangled relationship between politics and education, the selection of the reformers in a sense dictates the…

  5. A Rural Math, Science, and Technology Elementary School Tangled up in Global Networks of Practice

    ERIC Educational Resources Information Center

    Carlone, Heidi B.; Kimmel, Sue; Tschida, Christina

    2010-01-01

    This is an ethnographic study of a newly created math, science, and technology elementary magnet school in a rural community fiercely committed to cultural preservation while facing unprecedented economic instability brought on by massive loss of manufacturing jobs. Our goal was to understand global- and community-level contexts that influenced…

  6. Conflicted Worlds of Multilingual Communities in Africa: Literacy Tangled in Words

    ERIC Educational Resources Information Center

    Maganda, Dainess

    2016-01-01

    Drawing from a sociocultural perspective of literacy, with the goal to promote the use of African Native Languages (ANL) in schools, I conducted a Participatory Action Research in one multilingual primary school community in North West Tanzania. For three weeks, 19 teachers, 19 parents and 119 6th grade students collaborated with each other in a…

  7. "The Most Annoying Assignment Ever": Helping Composition Students Navigate New Vocabulary

    ERIC Educational Resources Information Center

    McKnight, Heal

    2010-01-01

    Almost all of the author's community college students feel self-conscious about their vocabulary. She thinks that their resistance to expanding their vocabulary has many tangled roots: sometimes the students seem nervous about what they leave behind as they notch their vocabulary up to a more formal, college level. This article discusses how the…

  8. Unraveling the Administrative Tangles in JMU's Speech Communication and General Education Programs.

    ERIC Educational Resources Information Center

    Emmert, Philip; Smilowitz, Michael

    What has transpired at James Madison University provides a model for the successful implementation of a basic communication education program required of all first-year students. This paper provides an accounting of the efforts that made possible the commitment to the development of the program. The paper is first divided into two columns. One…

  9. The Many-Headed Hydra of Theory vs. the Unifying Mission of Teaching.

    ERIC Educational Resources Information Center

    Gregory, Marshall

    1997-01-01

    Argues that students offer English departments a way of bypassing the tangle of theoretical disagreements and of gluing the fragmented pieces of the discipline back together again. Proposes that agreeing about principles of pedagogy is more urgent than agreeing about literary theory. Argues that English departments need to at least agree about…

  10. AspectAssay: A Technique for Expanding the Pool of Available Aspect Mining Test Data Using Concern Seeding

    ERIC Educational Resources Information Center

    Moore, David G., Jr.

    2013-01-01

    Aspect-oriented software design (AOSD) enables better and more complete separation of concerns in software-intensive systems. By extracting aspect code and relegating crosscutting functionality to aspects, software engineers can improve the maintainability of their code by reducing code tangling and coupling of code concerns. Further, the number…

  11. Herbicide treaments can improve your forest

    Treesearch

    James H. Miller

    1989-01-01

    When you plant a young pine stand after harvest, you mimic nature's seeding of the area. Then we often stand back and let nature take its course. Newly planted seedlings must divide their meager energy on two battlefronts: They must push and weave their roots through the tangle already there. At the same time, they must precariously struggle up through layers...

  12. Healthcare Crisis: Do Nurses Help or Hurt?

    PubMed

    Karnick, Paula M

    2017-01-01

    Healthcare is becoming a tangled web of dead ends, refusal of treatments by insurance companies who continue to report incredible profits, leaving many of the middle class and underserved without benefits, treatment, and care. The nursing profession must rise to this catastrophic state and strive for both in unison and individually so patients receive the care they need and deserve.

  13. Tangled Up in Views: Beliefs in the Nature of Science and Responses to Socioscientific Dilemmas.

    ERIC Educational Resources Information Center

    Zeidler, Dana L.; Walker, Kimberly A.; Ackett, Wayne A.; Simmons, Michael L.

    2002-01-01

    Investigates the relationship between students' conceptions of the nature of science and their reactions to evidence that challenged their beliefs about socioscientific issues. Stimulates students to reflect on their own beliefs and defend their opinions and suggests that the reaction of students to anomalous socioscientific data are varied and…

  14. Portrait of a molecule.

    PubMed

    Ball, Philip

    2003-01-23

    The double helix is idealized for its aesthetic elegant structure, but the reality of DNA's physical existence is quite different. Most DNA in the cell is compressed into a tangled package that somehow still exposes itself to meticulous gene-regulatory control. Philip Ball holds a mirror up to what we truly know about the mysteries of DNA's life inside a cell.

  15. Getting Tangled in the Web: A Systems Theory Approach to Supervision

    ERIC Educational Resources Information Center

    Orr, Penelope P.; Gussak, David E.

    2005-01-01

    The purpose of art therapy supervision in an educational setting has traditionally been seen as an opportunity to help interns adjust to and learn from their placement sites, understand their clients, develop an understanding of themselves in relation to their work, and translate theory into practice (Dye & Borders, 1990; Hawkins & Shoret, 1989;…

  16. The Tangled Web: Investigating Academics' Views of Plagiarism at the University of Cape Town

    ERIC Educational Resources Information Center

    de Jager, Karin; Brown, Cheryl

    2010-01-01

    This article considers the problematic question of student plagiarism, its causes and manifestations, and how it is addressed in academic environments. A literature survey was conducted to establish how higher education institutions approach these issues, and a twofold investigation was conducted at the University of Cape Town. Data was gathered…

  17. To No Avail: A Critical Look at the Charter School Debate

    ERIC Educational Resources Information Center

    Raymond, Margaret E.

    2014-01-01

    Maligned and revered, exemplified or reviled, almost every discussion about charter schools involves a tangle of differing histories, theories, values, and facts. Worse, many times the parties to the discussion aren't even aware they're operating on different planes of discourse. A sort of mental gridlock often results. But by separating…

  18. Tangled trends for temperate rain forests as temperatures tick up

    Treesearch

    Noreen Parks; Tara Barrett

    2013-01-01

    Climate change is altering growing conditions in the temperate rain forest region that extends from northern California to the Gulf of Alaska. Longer, warmer growing seasons are generally increasing the overall potential for forest growth in the region. However, species differ in their ability to adapt to changing conditions. For example, researchers with Pacific...

  19. Turning the Educability Narrative: Samuel A. Kirk at the Intersection of Learning Disability and "Mental Retardation"

    ERIC Educational Resources Information Center

    Danforth, Scot; Slocum, Laura; Dunkle, Jennifer

    2010-01-01

    It is often assumed that current disability constructs exist in conceptual isolation from one another. This article explores the tangled historical relationship between "mental retardation" and learning disability in the writings and speeches of special education pioneer Samuel A. Kirk. Beginning in the 1950s, Kirk repeatedly told an educability…

  20. Articulation to and from the Applied Associate Degree: Challenges and Opportunities

    ERIC Educational Resources Information Center

    Ignash, Jan M.

    2012-01-01

    This chapter discusses the "tangled knot" of articulating associate degrees in applied fields and reviews sample programs from applied associate (A.A.S.) to baccalaureate degrees using three distinct pathways, comparing the resulting A.A.S. to baccalaureate degree pathways to similar B.A. or B.S. programs. It focuses predominantly on curricular…

  1. Specific tackling situations affect the biomechanical demands experienced by rugby union players.

    PubMed

    Seminati, Elena; Cazzola, Dario; Preatoni, Ezio; Trewartha, Grant

    2017-03-01

    Tackling in Rugby Union is an open skill which can involve high-speed collisions and is the match event associated with the greatest proportion of injuries. This study aimed to analyse the biomechanics of rugby tackling under three conditions: from a stationary position, with dominant and non-dominant shoulder, and moving forward, with dominant shoulder. A specially devised contact simulator, a 50-kg punch bag instrumented with pressure sensors, was translated towards the tackler (n = 15) to evaluate the effect of laterality and tackling approach on the external loads absorbed by the tackler, on head and trunk motion, and on trunk muscle activities. Peak impact force was substantially higher in the stationary dominant (2.84 ± 0.74 kN) than in the stationary non-dominant condition (2.44 ± 0.64 kN), but lower than in the moving condition (3.40 ± 0.86 kN). Muscle activation started on average 300 ms before impact, with higher activation for impact-side trapezius and non-impact-side erector spinae and gluteus maximus muscles. Players' technique for non-dominant-side tackles was less compliant with current coaching recommendations in terms of cervical motion (more neck flexion and lateral bending in the stationary non-dominant condition) and players could benefit from specific coaching focus on non-dominant-side tackles.

  2. 46 CFR 160.061-5 - Marking.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Fishing Tackle Kits, Emergency, for Merchant Vessels § 160.061-5... FISHING TACKLE KIT OPEN ONLY FOR ACTUAL EMERGENCY USE NOT FOR INSPECTION (b) [Reserved] ...

  3. 46 CFR 160.061-5 - Marking.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Fishing Tackle Kits, Emergency, for Merchant Vessels § 160.061-5... FISHING TACKLE KIT OPEN ONLY FOR ACTUAL EMERGENCY USE NOT FOR INSPECTION (b) [Reserved] ...

  4. 46 CFR 160.061-5 - Marking.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Fishing Tackle Kits, Emergency, for Merchant Vessels § 160.061-5... FISHING TACKLE KIT OPEN ONLY FOR ACTUAL EMERGENCY USE NOT FOR INSPECTION (b) [Reserved] ...

  5. 46 CFR 160.061-5 - Marking.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Fishing Tackle Kits, Emergency, for Merchant Vessels § 160.061-5... FISHING TACKLE KIT OPEN ONLY FOR ACTUAL EMERGENCY USE NOT FOR INSPECTION (b) [Reserved] ...

  6. 46 CFR 160.061-5 - Marking.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...: SPECIFICATIONS AND APPROVAL LIFESAVING EQUIPMENT Fishing Tackle Kits, Emergency, for Merchant Vessels § 160.061-5... FISHING TACKLE KIT OPEN ONLY FOR ACTUAL EMERGENCY USE NOT FOR INSPECTION (b) [Reserved] ...

  7. Physical Allergy

    MedlinePlus

    ... Fall Allergies Before Tackling the Leaves (News) Can Trees Curb Asthma Flare-Ups in Polluted Cities? (News) ... Allergies Before Tackling the Leaves News HealthDay Can Trees Curb Asthma Flare-Ups in Polluted Cities? News ...

  8. Broadband, Low-Loss Phase Shifters Based on Thin Ferroelectric Films

    NASA Technical Reports Server (NTRS)

    Romanofsky, Robert

    2004-01-01

    Several different types of microwave transmission line phase shifters based on thin ferroelectic films have been developed at the NASA Glenn Research Center. These include a series of coupled microstrip lines, slotline incorporating Marchand balms, odd-mode coplanar strips, and hybrid devices incorporating a switch to toggle the output termination between an open and virtual short circuit. A review of the theory of operation of each of these devices will be presented along with measured performance. Also, devices of the first variety have been subjected to total dose (proton) radiation exposure using a 200 MeV beam energy with a total dose up to nearly 1 kRad (Si). Results of these radiation tests will be discussed.

  9. Mammalian synthetic biology: emerging medical applications

    PubMed Central

    Kis, Zoltán; Pereira, Hugo Sant'Ana; Homma, Takayuki; Pedrigi, Ryan M.; Krams, Rob

    2015-01-01

    In this review, we discuss new emerging medical applications of the rapidly evolving field of mammalian synthetic biology. We start with simple mammalian synthetic biological components and move towards more complex and therapy-oriented gene circuits. A comprehensive list of ON–OFF switches, categorized into transcriptional, post-transcriptional, translational and post-translational, is presented in the first sections. Subsequently, Boolean logic gates, synthetic mammalian oscillators and toggle switches will be described. Several synthetic gene networks are further reviewed in the medical applications section, including cancer therapy gene circuits, immuno-regulatory networks, among others. The final sections focus on the applicability of synthetic gene networks to drug discovery, drug delivery, receptor-activating gene circuits and mammalian biomanufacturing processes. PMID:25808341

  10. Inaccessible Masturbation, Impossible Mourning: Collective Melancholia, the Prohibition on Female Sexual Subjects in India, and Masturbation Fantasy as a Zone of the Strange.

    PubMed

    Narayanan, A

    2015-12-01

    This paper explores a subjective experience-and identification-that a cohort of Indian women identifies as "home." This experience of "home" provides an attachment to a collective melancholia that keeps in place a prohibited female sexual subjectivity. The paper provides a brief historical overview of the prohibition of female sexual subjectivity and erotic agency in India. Following this, it discusses women's masturbation fantasies that illustrate the toggle between women's permitted and prohibited identifications. A clinical case example is presented to illustrate the hopelessness and mourning inherent in the psychoanalytic journey into subjectivity, a journey involving a departure from a shared cultural history.

  11. What Are Islet Cells?

    MedlinePlus

    ... to put the cells What is Islet Transplantation? Sustainability - Tackling the immune system Supply - Creating more cells ... to put the cells What is Islet Transplantation? Sustainability - Tackling the immune system Supply - Creating more cells ...

  12. A Tangled Web of Terms: The Overlap and Unique Contribution of Involvement, Engagement, and Integration to Understanding College Student Success

    ERIC Educational Resources Information Center

    Wolf-Wendel, Lisa; Ward, Kelly; Kinzie, Jillian

    2009-01-01

    Established theories and constructs long associated with student success, including involvement, engagement, and integration, provide common language and a body of knowledge to inform understanding of the challenges currently facing higher education. This paper examines how the theories and terms have evolved, explores how the terms are currently…

  13. Teaching with Crystal Structures: Helping Students Recognize and Classify the Smallest Repeating Particle in a Given Substance

    ERIC Educational Resources Information Center

    Smithenry, Dennis W.

    2009-01-01

    Classifying a particle requires an understanding of the type of bonding that exists within and among the particles, which requires an understanding of atomic structure and electron configurations, which requires an understanding of the elements of periodic properties, and so on. Rather than getting tangled up in all of these concepts at the start…

  14. The effect of the dye Aquashade(c) on water quality, phytoplankton, zooplankton, and sunshine bass fingerling production in fertilized culture ponds

    USDA-ARS?s Scientific Manuscript database

    Rooted macrophytes make harvesting fingerling sunshine bass from ponds difficult because they can smother fish or tangle in the seines and increase fish stress by increasing time needed to retrieve the fingerlings from the net. Aquashade® is a dye that is used to reduce macrophyte growth by reducin...

  15. Stimulus Patching Budgets: Local Officials Crying Foul as Governors Grab for Aid

    ERIC Educational Resources Information Center

    McNell, Michele

    2009-01-01

    Desperate for cash to fill growing budget deficits, state governments are starting to tangle with federal and local officials over a $39.8 billion pot of economic-stimulus money that was designed to prop up the budgets of local school districts, but is increasingly being eyed as a patch for states' own financial woes. Vague language and loopholes…

  16. Archaeology and astronomy

    NASA Astrophysics Data System (ADS)

    2009-10-01

    MEETING REPORT The interaction between archaeology and astronomy has a long, tangled and not entirely creditable history, marred by misunderstandings on both sides. But statistics and cultural awareness are bringing a better picture of how and why lasting monuments such as Stonehenge were built. Sue Bowler reports on a joint meeting of the Royal Astronomical Society and the Prehistoric Society, held at Jodrell Bank on 17 July 2009.

  17. A Tangled Weave: Tracing Outcomes of Education in Rural Women's Lives in North India

    ERIC Educational Resources Information Center

    Ghose, Malini; Mullick, Disha

    2015-01-01

    This paper is based on the findings of a research study which traced 56 rural women learners 15 years after they had participated in an empowerment and education programme in North India. It attempts to understand, from the perspectives of women from marginalised communities, the ways in which participating in the programme had been empowering for…

  18. 46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

  19. 46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

  20. 46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

  1. 46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

  2. 46 CFR 173.025 - Additional intact stability standards: Counterballasted vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of heel. T=angle of heel. EC01MR91.028 Where— GZ(1) is the righting arm curve at the displacement corresponding to the vessel without hooking load. GZ(2) is the righting arm curve at the displacement... of the hook load and the counterballast at the displacement with hook load. HA(2) is the heeling arm...

  3. The Tangled World of Teacher Debt: Clashing Rules and Uncertain Benefits for Federal Student-Loan Subsidies

    ERIC Educational Resources Information Center

    Delisle, Jason; Holt, Alexander

    2017-01-01

    The world of student loans and debt forgiveness for teachers is a patchwork of overlapping programs, contradictory regulations, and expensive subsidies that date back to Dwight D. Eisenhower's signing of the National Defense Education Act of 1958. The 60-year experiment in using federal loan dollars to encourage students to become teachers could…

  4. Collaborative Decision Making in METOC

    DTIC Science & Technology

    2002-01-01

    desired effect (Eagly, & Chaiken, 1993). Arguably, artificial intelligence is representative of the best of approaches in rational decision - making ...2001), The quantum of social action and the function of emotion in decision - making , Emotional and Intelligent II: The Tangled Knot of Social...Collaborative decision making in METOC W.F. Lawless Paine College, Departments of Mathematics and Psychology Augusta, GA 30901-3182 ph: 706

  5. Race to Top Round Two Heating Up

    ERIC Educational Resources Information Center

    McNeil, Michele

    2010-01-01

    With the second-round deadline for federal Race to the Top Fund grants less than six weeks away, states are rushing to raise the stakes on their education reform plans as they fight over the remaining $3.4 billion in prize money. But in doing so, states from Massachusetts to Colorado are tangling with their teachers' unions as they test how far…

  6. Lycopene Supplementation in the Complementary Management of PSA Failure: A Randomized Placebo-Controlled Trial for Prostate Cancer Survivors

    DTIC Science & Technology

    2007-01-01

    Morris JC, Hulette C, Schmechel D, Reiman EM, Rogers J, Stephan DA. (2005). Gene expression correlates of neurofibrillary tangles in Alzheimer’s...Walker DG, Lafleur BJ, Coon KD, Brown KM, Caselli R, Kukull W, Higdon R, McKeel D, Morris JC, Hulette C, Schmechel D, Reiman EM, Rogers J, Stephan

  7. Make a Path for Evaluation: 10 Stepping Stones Help Leaders Build Solid Practices

    ERIC Educational Resources Information Center

    Champion, Robby

    2015-01-01

    If professional learning leaders are looking for a clear path lined with models of best program evaluation practices, they will become tangled in the weeds. After working for several decades to help professional learning leaders and their teams improve programs and evaluations, the author has observed several habits of mind and work that can make…

  8. Beyond City Limits: Cross-System Collaboration to Reengage Disconnected Youth

    ERIC Educational Resources Information Center

    Moore, Andrew

    2007-01-01

    For young people who have dropped out of school, are out of work, or lack connections to family or other caring adults, there are often no easy answers. Their hopes for a better life are frequently no different than those harbored by their more advantaged peers, but their path to adulthood is rendered more difficult by tangled combinations of…

  9. A new one-man submarine is tested as vehicle for solid rocket booster retrieval

    NASA Technical Reports Server (NTRS)

    2000-01-01

    At left, a manipulator arm on a one-man submarine demonstrates its ability to cut tangled parachute riser lines and place a Diver Operator Plug (top right) inside a mock solid rocket booster nozzle (center). Known as DeepWorker 2000, the sub is being tested on its ability to duplicate the sometimes hazardous job United Space Alliance (USA) divers perform to recover the expended boosters in the ocean after a launch. The boosters splash down in an impact area about 140 miles east of Jacksonville and after recovery are towed back to KSC for refurbishment by the specially rigged recovery ships. DeepWorker 2000 will be used in a demonstration during retrieval operations after the upcoming STS-101 launch. The submarine pilot will demonstrate capabilities to cut tangled parachute riser lines using a manipulator arm and attach the DOP to extract water and provide flotation for the booster. DeepWorker 2000 was built by Nuytco Research Ltd., North Vancouver, British Columbia. It is 8.25 feet long, 5.75 feet high, and weighs 3,800 pounds. USA is a prime contractor to NASA for the Space Shuttle program.

  10. The APOE4 allele shows opposite sex bias in microbleeds and Alzheimer’s Disease of humans and mice

    PubMed Central

    Cacciottolo, Mafalda; Christensen, Amy; Moser, Alexandra; Liu, Jiahui; Pike, Christian J.; Sullivan, Patrick M.; Morgan, Todd E.; Dolzhenko, Egor; Charidimou, Andreas; Wahlund, Lars-Olaf; Wiberg, Maria Kristofferson; Shams, Sara; Chiang, Gloria Chia-Yi; Finch, Caleb E.

    2015-01-01

    The APOE4 allele confers greater risk of Alzheimer’s Disease (AD) for women than men, in conjunction with greater clinical deficits per unit of AD neuropathology (plaques, tangles). Cerebral microbleeds, which contribute to cognitive dysfunctions during AD, also show APOE4 excess, but sex-APOE allele interactions are not described. We report that elderly men diagnosed for mild cognitive impairment (MCI) and AD showed a higher risk of cerebral cortex microbleeds with APOE4 allele dose effect in two clinical cohorts (ADNI and KIDS). Sex-APOE interactions were further analyzed in EFAD mice carrying human APOE alleles and familial AD genes. At 7 months, E4FAD mice had cerebral cortex microbleeds with female excess, in contrast to humans. Cerebral amyloid angiopathy (CAA), plaques, and soluble Aβ also showed female excess. Both the cerebral microbleeds and CAA increased in proportion to individual Aβ load. In humans, the opposite sex bias of APOE4 allele for microbleeds vs the plaques and tangles is the first example of organ-specific, sex-linked APOE allele effects, and further shows AD as a uniquely human condition. PMID:26686669

  11. The APOE4 allele shows opposite sex bias in microbleeds and Alzheimer's disease of humans and mice.

    PubMed

    Cacciottolo, Mafalda; Christensen, Amy; Moser, Alexandra; Liu, Jiahui; Pike, Christian J; Smith, Conor; LaDu, Mary Jo; Sullivan, Patrick M; Morgan, Todd E; Dolzhenko, Egor; Charidimou, Andreas; Wahlund, Lars-Olof; Wiberg, Maria Kristofferson; Shams, Sara; Chiang, Gloria Chia-Yi; Finch, Caleb E

    2016-01-01

    The apolipoprotein APOE4 allele confers greater risk of Alzheimer's disease (AD) for women than men, in conjunction with greater clinical deficits per unit of AD neuropathology (plaques, tangles). Cerebral microbleeds, which contribute to cognitive dysfunctions during AD, also show APOE4 excess, but sex-APOE allele interactions are not described. We report that elderly men diagnosed for mild cognitive impairment and AD showed a higher risk of cerebral cortex microbleeds with APOE4 allele dose effect in 2 clinical cohorts (ADNI and KIDS). Sex-APOE interactions were further analyzed in EFAD mice carrying human APOE alleles and familial AD genes (5XFAD (+/-) /human APOE(+/+)). At 7 months, E4FAD mice had cerebral cortex microbleeds with female excess, in contrast to humans. Cerebral amyloid angiopathy, plaques, and soluble Aβ also showed female excess. Both the cerebral microbleeds and cerebral amyloid angiopathy increased in proportion to individual Aβ load. In humans, the opposite sex bias of APOE4 allele for microbleeds versus the plaques and tangles is the first example of organ-specific, sex-linked APOE allele effects, and further shows AD as a uniquely human condition. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. The neuropathology of chronic traumatic encephalopathy.

    PubMed

    McKee, Ann C; Stein, Thor D; Kiernan, Patrick T; Alvarez, Victor E

    2015-05-01

    Repetitive brain trauma is associated with a progressive neurological deterioration, now termed as chronic traumatic encephalopathy (CTE). Most instances of CTE occur in association with the play of sports, but CTE has also been reported in association with blast injuries and other neurotrauma. Symptoms of CTE include behavioral and mood changes, memory loss, cognitive impairment and dementia. Like many other neurodegenerative diseases, CTE is diagnosed with certainty only by neuropathological examination of brain tissue. CTE is a tauopathy characterized by the deposition of hyperphosphorylated tau (p-tau) protein as neurofibrillary tangles, astrocytic tangles and neurites in striking clusters around small blood vessels of the cortex, typically at the sulcal depths. Severely affected cases show p-tau pathology throughout the brain. Abnormalities in phosphorylated 43 kDa TAR DNA-binding protein are found in most cases of CTE; beta-amyloid is identified in 43%, associated with age. Given the importance of sports participation and physical exercise to physical and psychological health as well as disease resilience, it is critical to identify the genetic risk factors for CTE as well as to understand how other variables, such as stress, age at exposure, gender, substance abuse and other exposures, contribute to the development of CTE. © 2015 International Society of Neuropathology.

  13. Susceptibility to neurofibrillary tangles: role of the PTPRD locus and limited pleiotropy with other neuropathologies.

    PubMed

    Chibnik, L B; White, C C; Mukherjee, S; Raj, T; Yu, L; Larson, E B; Montine, T J; Keene, C D; Sonnen, J; Schneider, J A; Crane, P K; Shulman, J M; Bennett, D A; De Jager, P L

    2017-03-21

    Tauopathies, including Alzheimer's disease (AD) and other neurodegenerative conditions, are defined by a pathological hallmark: neurofibrillary tangles (NFTs). NFT accumulation is thought to be closely linked to cognitive decline in AD. Here, we perform a genome-wide association study for NFT pathologic burden and report the association of the PTPRD locus (rs560380, P=3.8 × 10 -8 ) in 909 prospective autopsies. The association is replicated in an independent data set of 369 autopsies. The association of PTPRD with NFT is not dependent on the accumulation of amyloid pathology. In contrast, we found that the ZCWPW1 AD susceptibility variant influences NFT accumulation and that this effect is mediated by an accumulation of amyloid β plaques. We also performed complementary analyses to identify common pathways that influence multiple neuropathologies that coexist with NFT and found suggestive evidence that certain loci may influence multiple different neuropathological traits, including tau, amyloid β plaques, vascular injury and Lewy bodies. Overall, these analyses offer an evaluation of genetic susceptibility to NFT, a common end point for multiple different pathologic processes.Molecular Psychiatry advance online publication, 21 March 2017; doi:10.1038/mp.2017.20.

  14. Cholinergic and dopaminergic activities in senile dementia of Lewy body type.

    PubMed

    Perry, E K; Marshall, E; Perry, R H; Irving, D; Smith, C J; Blessed, G; Fairbairn, A F

    1990-01-01

    Analyses of brain tissue in a recently identified group of elderly demented patients suggest a neurochemical basis for some of the clinical features. Senile dementia of the Lewy body type (SDLT) can be distinguished from classical Alzheimer disease (AD) clinically by its acute presentation with confusion frequently accompanied by visual hallucinations, and neuropathologically by the presence of Lewy bodies and senile plaques (but not generally neurofibrillary tangles) in the cerebral cortex. Reductions in the cortical cholinergic enzyme choline acetyltransferase were more pronounced in individuals with (80%) compared to those without (50%) hallucinations and correlated strongly with mental test scores in the group as a whole. In the caudate nucleus, dopamine levels were related to the number of neurons in the substantia nigra, there being a 40-60% loss of both in SDLT--probably accounting for mild extrapyramidal features in some of these cases--compared with an 80% loss in Parkinson disease and no change in AD. The cholinergic correlates of mental impairment in SDLT together with the relative absence of cortical neurofibrillary tangles and evidence for postsynaptic cholinergic receptor compensation raise the question of whether this type of dementia may be more amenable to cholinotherapy than classical AD.

  15. Modeling non-stationary, non-axisymmetric heat patterns in DIII-D tokamak

    DOE PAGES

    Ciro, D.; Evans, T. E.; Caldas, I. L.

    2016-10-27

    Non-axisymmetric stationary magnetic perturbations lead to the formation of homoclinic tangles near the divertor magnetic saddle in tokamak discharges. These tangles intersect the divertor plates in static helical structures that delimit the regions reached by open magnetic field lines reaching the plasma column and leading the charged particles to the strike surfaces by parallel transport. In this article we introduce a non-axisymmetric rotating magnetic perturbation to model the time evolution of the three-dimensional magnetic field of a singlenull DIII-D tokamak discharge developing a rotating tearing mode. The non-axiymmetric field is modeled using the magnetic signals to adjust the phases andmore » currents of a set of internal filamentary currents that approximate the magnetic field in the plasma edge region. The stable and unstable manifolds of the asymmetric magnetic saddle are obtained through an adaptive calculation providing the cuts at a given poloidal plane and the strike surfaces. Lastly, for the modeled shot, the experimental heat pattern and its time development are well described by the rotating unstable manifold, indicating the emergence of homoclinic lobes in a rotating frame due to the plasma instabilities.« less

  16. Modeling non-stationary, non-axisymmetric heat patterns in DIII-D tokamak

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ciro, D.; Evans, T. E.; Caldas, I. L.

    Non-axisymmetric stationary magnetic perturbations lead to the formation of homoclinic tangles near the divertor magnetic saddle in tokamak discharges. These tangles intersect the divertor plates in static helical structures that delimit the regions reached by open magnetic field lines reaching the plasma column and leading the charged particles to the strike surfaces by parallel transport. In this article we introduce a non-axisymmetric rotating magnetic perturbation to model the time evolution of the three-dimensional magnetic field of a singlenull DIII-D tokamak discharge developing a rotating tearing mode. The non-axiymmetric field is modeled using the magnetic signals to adjust the phases andmore » currents of a set of internal filamentary currents that approximate the magnetic field in the plasma edge region. The stable and unstable manifolds of the asymmetric magnetic saddle are obtained through an adaptive calculation providing the cuts at a given poloidal plane and the strike surfaces. Lastly, for the modeled shot, the experimental heat pattern and its time development are well described by the rotating unstable manifold, indicating the emergence of homoclinic lobes in a rotating frame due to the plasma instabilities.« less

  17. An inconspicuous, conspicuous new species of Asian pipesnake, genus Cylindrophis (Reptilia: Squamata: Cylindrophiidae), from the south coast of Jawa Tengah, Java, Indonesia, and an overview of the tangled taxonomic history of C. ruffus (Laurenti, 1768).

    PubMed

    Kieckbusch, Max; Mecke, Sven; Hartmann, Lukas; Ehrmantraut, Lisa; O'shea, Mark; Kaiser, Hinrich

    2016-03-20

    We describe a new species of Cylindrophis currently known only from Grabag, Purworejo Regency, Jawa Tengah Pro-vince (Central Java), Java, Indonesia. Cylindrophis subocularis sp. nov. can be distinguished from all congeners by the presence of a single, eponymous subocular scale between the 3rd and 4th or 4th and 5th supralabial, preventing contact between the 4th or 5th supralabial and the orbit, and by having the prefrontal in narrow contact with or separated from the orbit. We preface our description with a detailed account of the tangled taxonomic history of the similar and putatively wide-ranging species C. ruffus, which leads us to (1) remove the name Scytale scheuchzeri from the synonymy of C. ruffus, (2) list the taxon C. rufa var. javanica as species inquirenda, and (3) synonymize C. mirzae with C. ruffus. We provide additional evidence to confirm that the type locality of C. ruffus is Java. Cylindrophis subocularis sp. nov. is the second species of Asian pipesnake from Java.

  18. Anxiety-like behavior as an early endophenotype in the TgF344-AD rat model of Alzheimer's disease.

    PubMed

    Pentkowski, Nathan S; Berkowitz, Laura E; Thompson, Shannon M; Drake, Emma N; Olguin, Carlos R; Clark, Benjamin J

    2018-01-01

    Alzheimer's disease (AD) is characterized by progressive cognitive decline and the presence of aggregates of amyloid beta (plaques) and hyperphosphorylated tau (tangles). Early diagnosis through neuropsychological testing is difficult due to comorbidity of symptoms between AD and other types of dementia. As a result, there is a need to identify the range of behavioral phenotypes expressed in AD. In the present study, we utilized a transgenic rat (TgF344-AD) model that bears the mutated amyloid precursor protein as well as presenilin-1 genes, resulting in progressive plaque and tangle pathogenesis throughout the cortex. We tested young adult male and female TgF344-AD rats in a spatial memory task in the Morris water maze and for anxiety-like behavior in the elevated plus-maze. Results indicated that regardless of sex, TgF344-AD rats exhibited increased anxiety-like behavior in the elevated plus-maze, which occurred without significant deficits in the spatial memory. Together, these results indicate that enhanced anxiety-like behavior represents an early-stage behavioral marker in the TgF344-AD rat model. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. The Neuropathology of Chronic Traumatic Encephalopathy

    PubMed Central

    McKee, Ann C.; Stein, Thor D.; Kiernan, Patrick T.; Alvarez, Victor E.

    2015-01-01

    Repetitive brain trauma is associated with a progressive neurological deterioration, now termed as chronic traumatic encephalopathy (CTE). Most instances of CTE occur in association with the play of sports, but CTE has also been reported in association with blast injuries and other neurotrauma. Symptoms of CTE include behavioral and mood changes, memory loss, cognitive impairment and dementia. Like many other neurodegenerative diseases, CTE is diagnosed with certainty only by neuropathological examination of brain tissue. CTE is a tauopathy characterized by the deposition of hyperphosphorylated tau (p-tau) protein as neurofibrillary tangles, astrocytic tangles and neurites in striking clusters around small blood vessels of the cortex, typically at the sulcal depths. Severely affected cases show p-tau pathology throughout the brain. Abnormalities in phosphorylated 43 kDa TAR DNA-binding protein are found in most cases of CTE; beta-amyloid is identified in 43%, associated with age. Given the importance of sports participation and physical exercise to physical and psychological health as well as disease resilience, it is critical to identify the genetic risk factors for CTE as well as to understand how other variables, such as stress, age at exposure, gender, substance abuse and other exposures, contribute to the development of CTE. PMID:25904048

  20. Chronic Traumatic Encephalopathy in Athletes: Progressive Tauopathy following Repetitive Head Injury

    PubMed Central

    McKee, Ann C.; Cantu, Robert C.; Nowinski, Christopher J.; Hedley-Whyte, E. Tessa; Gavett, Brandon E.; Budson, Andrew E.; Santini, Veronica E.; Lee, Hyo-Soon; Kubilus, Caroline A.; Stern, Robert A.

    2009-01-01

    Since the 1920s, it has been known that the repetitive brain trauma associated with boxing may produce a progressive neurological deterioration, originally termed “dementia pugilistica” and more recently, chronic traumatic encephalopathy (CTE). We review the 47 cases of neuropathologically verified CTE recorded in the literature and document the detailed findings of CTE in 3 professional athletes: one football player and 2 boxers. Clinically, CTE is associated with memory disturbances, behavioral and personality changes, Parkinsonism, and speech and gait abnormalities. Neuropathologically, CTE is characterized by atrophy of the cerebral hemispheres, medial temporal lobe, thalamus, mammillary bodies, and brainstem, with ventricular dilatation and a fenestrated cavum septum pellucidum. Microscopically, there are extensive tau-immunoreactive neurofibrillary tangles, astrocytic tangles, and spindle-shaped and threadlike neurites throughout the brain. The neurofibrillary degeneration of CTE is distinguished from other tauopathies by preferential involvement of the superficial cortical layers, irregular, patchy distribution in the frontal and temporal cortices, propensity for sulcal depths, prominent perivascular, periventricular and subpial distribution, and marked accumulation of tau-immunoreactive astrocytes. Deposition of beta amyloid, most commonly as diffuse plaques, occurs in fewer than half the cases. CTE is a neuropathologically distinct, slowly progressive tauopathy with a clear environmental etiology. PMID:19535999

  1. Chronic Traumatic Encephalopathy: A Potential Late Effect of Sport-Related Concussive and Subconcussive Head Trauma1

    PubMed Central

    Gavett, Brandon E.; Stern, Robert A.; McKee, Ann C.

    2010-01-01

    Synopsis Chronic traumatic encephalopathy (CTE) is a form of neurodegeneration that is believed to result from repeated head injuries. Originally termed dementia pugilistica due to its association with boxing, the neuropathology of CTE was first described by Corsellis in 1973 in a case series of 15 retired boxers. CTE has recently been found to occur following other causes of repeated head trauma, suggesting that any repeated blows to the head, such as those that occur due to American football, hockey, soccer, professional wrestling, and physical abuse, can also lead to neurodegenerative changes. These changes often include cerebral atrophy, cavum septum pellucidum with fenestrations, shrinkage of the mammillary bodies, dense tau immunoreactive inclusions (neurofibrillary tangles, glial tangles, and neuropil neurites), diffuse axonal injury, and, in some cases, a TDP-43 proteinopathy. In association with these pathological changes, affected individuals often exhibit disordered memory and executive functioning, behavioral and personality disturbances (e.g., apathy, depression, irritability, impulsiveness, suicidality), parkinsonism, and, occasionally, motor neuron disease. At the present time, there are no formal clinical or pathological diagnostic criteria for CTE, but the distinctive neuropathological profile of the disorder lends promise for future research into its prevention, diagnosis, and treatment. PMID:21074091

  2. Mechanisms and Factors Associated With Tackle-Related Injuries in South African Youth Rugby Union Players.

    PubMed

    Burger, Nicholas; Lambert, Mike Ian; Viljoen, Wayne; Brown, James Craig; Readhead, Clint; den Hollander, Steve; Hendricks, Sharief

    2017-02-01

    The majority of injuries in rugby union occur during tackle events. The mechanisms and causes of these injuries are well established in senior rugby union. To use information from an injury database and assess video footage of tackle-related injuries in youth rugby union matches to identify environmental factors and mechanisms that are potentially confounding to these injuries. Descriptive epidemiological study. Injury surveillance was conducted at the under-18 Craven Week rugby tournament. Tackle-related injury information was used to identify injury events in match video footage (role-matched noninjury tackle events were identified for the cohort of injured players). Events were coded using match situational variables (precontact, contact, and postcontact). Relative risk ratio (RRR; ratio of probability of an injury or noninjury outcome occurring when a characteristic was observed) was reported by use of logistic regression. In comparison with the first quarter, injury risk was greater in the third (RRR = 9.75 [95% CI, 1.71-55.64]; P = .010) and fourth quarters (RRR = 6.97 [95% CI, 1.09-44.57]; P = .040) for ball carriers and in the fourth quarter (RRR = 9.63 [95% CI, 1.94-47.79]; P = .006) for tacklers. Ball carriers were less likely to be injured when they were aware of impending contact (RRR = 0.14 [95% CI, 0.03-0.66]; P = .012) or when they executed a moderate fend (hand-off) (RRR = 0.22 [95% CI, 0.06-0.84]; P = .026). Tacklers were less likely to be injured when performing shoulder tackles (same side as leading leg) in comparison to an arm-only tackle (RRR = 0.02 [95% CI, 0.001-0.79]; P = .037). Ball carriers (RRR = 0.09 [95% CI, 0.01-0.89]; P = .040) and tacklers (RRR = 0.02 [95% CI, 0.001-0.32]; P =.006) were less likely to be injured when initial contact was made with the tackler's shoulder/arm instead of his head/neck. The relative risk of tackle-related injury was higher toward the end of matches. Incorrect technique may contribute to increased injury risk. Implementing recovery strategies between matches, training safe and effective techniques, and improving levels of conditioning may counter the negative effects of fatigue. These findings may assist stakeholders in youth rugby to formulate injury prevention strategies and may improve the preparation of field-side medical staff for managing tackle-related injuries at these or similar tournaments.

  3. SU-F-19A-10: Recalculation and Reporting Clinical HDR 192-Ir Head and Neck Dose Distributions Using Model Based Dose Calculation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Carlsson Tedgren, A; Persson, M; Nilsson, J

    Purpose: To retrospectively re-calculate dose distributions for selected head and neck cancer patients, earlier treated with HDR 192Ir brachytherapy, using Monte Carlo (MC) simulations and compare results to distributions from the planning system derived using TG43 formalism. To study differences between dose to medium (as obtained with the MC code) and dose to water in medium as obtained through (1) ratios of stopping powers and (2) ratios of mass energy absorption coefficients between water and medium. Methods: The MC code Algebra was used to calculate dose distributions according to earlier actual treatment plans using anonymized plan data and CT imagesmore » in DICOM format. Ratios of stopping power and mass energy absorption coefficients for water with various media obtained from 192-Ir spectra were used in toggling between dose to water and dose to media. Results: Differences between initial planned TG43 dose distributions and the doses to media calculated by MC are insignificant in the target volume. Differences are moderate (within 4–5 % at distances of 3–4 cm) but increase with distance and are most notable in bone and at the patient surface. Differences between dose to water and dose to medium are within 1-2% when using mass energy absorption coefficients to toggle between the two quantities but increase to above 10% for bone using stopping power ratios. Conclusion: MC predicts target doses for head and neck cancer patients in close agreement with TG43. MC yields improved dose estimations outside the target where a larger fraction of dose is from scattered photons. It is important with awareness and a clear reporting of absorbed dose values in using model based algorithms. Differences in bone media can exceed 10% depending on how dose to water in medium is defined.« less

  4. Contact events in rugby union and their propensity to cause injury

    PubMed Central

    Fuller, Colin W; Brooks, John H M; Cancea, Rebecca J; Hall, John; Kemp, Simon P T

    2007-01-01

    Objective The objective of this study was to determine the incidence of contact events in professional rugby union matches and to assess their propensity to cause injury. Design The study was a two‐season (2003/2004 and 2005/2006) prospective cohort design. It included 645 professional rugby union players from 13 English Premiership rugby union clubs. The main outcome measures were: incidence of match contact events (events per game); incidence (injuries per 1000 player‐hours and per 1000 contact events), risk (days lost per 1000 player‐hours and per 1000 contact events) and diagnosis of injury; referee's decision. Risk factors were player–player contact, position on pitch and period of play. Results Tackles (221.0 events/game) and rucks (142.5 events/game) were the most common events and mauls (13.6%) and scrums (12.6%) the most penalised. Tackles (701.6 days/1000 player‐hours) were responsible for the greatest loss of time but scrums (213.2 days lost/1000 events) and collisions (199.8 days lost/1000 events) presented the highest risk per event. Conclusions Tackles were the game event responsible for the highest number of injuries and the greatest loss of time in rugby union because they were by far the most common contact event. Collisions were 70% more likely to result in an injury than a tackle and scrums carried a 60% greater risk of injury than a tackle. The relative propensities for contact events to cause injury were rated as: lineout – very low; ruck – low; maul and tackle – average; collision and scrum – high. PMID:17513332

  5. Contact events in rugby union and their propensity to cause injury.

    PubMed

    Fuller, Colin W; Brooks, John H M; Cancea, Rebecca J; Hall, John; Kemp, Simon P T

    2007-12-01

    The objective of this study was to determine the incidence of contact events in professional rugby union matches and to assess their propensity to cause injury. The study was a two-season (2003/2004 and 2005/2006) prospective cohort design. It included 645 professional rugby union players from 13 English Premiership rugby union clubs. The main outcome measures were: incidence of match contact events (events per game); incidence (injuries per 1000 player-hours and per 1000 contact events), risk (days lost per 1000 player-hours and per 1000 contact events) and diagnosis of injury; referee's decision. Risk factors were player-player contact, position on pitch and period of play. Tackles (221.0 events/game) and rucks (142.5 events/game) were the most common events and mauls (13.6%) and scrums (12.6%) the most penalised. Tackles (701.6 days/1000 player-hours) were responsible for the greatest loss of time but scrums (213.2 days lost/1000 events) and collisions (199.8 days lost/1000 events) presented the highest risk per event. Tackles were the game event responsible for the highest number of injuries and the greatest loss of time in rugby union because they were by far the most common contact event. Collisions were 70% more likely to result in an injury than a tackle and scrums carried a 60% greater risk of injury than a tackle. The relative propensities for contact events to cause injury were rated as: lineout--very low; ruck--low; maul and tackle--average; collision and scrum--high.

  6. 2. VIEW OF BLOCK AND TACKLE FOR MOVING CEDAR LOGS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW OF BLOCK AND TACKLE FOR MOVING CEDAR LOGS FROM POND TO JACK LADDER--AN ENDLESS CHAIN CONVEYOR THAT MOVES LOGS INTO MILL - Lester Shingle Mill, 1602 North Eighteenth Street, Sweet Home, Linn County, OR

  7. Theoretical Framework for Interaction Game Design

    DTIC Science & Technology

    2016-05-19

    the more is shared among the participants, the more empathy is gained. We believe that common ground, defined as presuppositions for conversation...shared among the participants, the more empathy is gained.” We have not tried to dive for the ultimate success—realization of a comprehensive...intentions tangle in a complex fashion. Participants were asked to annotate scenes by adding comments of eight types: clarification, confirmation, empathy

  8. 76 FR 16807 - Notice of Intent To Collect Fees on Public Land in Tangle Lakes, Alaska, Glennallen Field Office...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-25

    ... Denali Highway at milepost 21.5 and lies within the nationally designated Delta Wild and Scenic River... designated campsites with tables, tent or trailer space and fire rings, as well as a picnic area, parking... the update of the Delta Wild and Scenic River management plan. The public was provided details of the...

  9. The anatomy of the mermaid.

    PubMed

    Heppell, D

    Investigation of the anatomy of the mermaid and of mermaid lore has revealed a tangled web of stories, sightings and specimens of the most diverse nature, extending worldwide into the realms of folklore and legend, zoology and cryptozoology, anatomy, physiology, radiography and folk medicine, ethnography, social history and the history of science. The stereotype we know as the mermaid is surely a fit subject for further serious study

  10. An entropic model of Gaia.

    PubMed

    Arthur, R; Nicholson, A

    2017-10-07

    We modify the Tangled Nature Model of Christensen et. al. (2002) so that the agents affect the carrying capacity. This leads to a model of species-environment co-evolution where the system tends to have a larger carrying capacity with life than without. We discuss the model as an example of an entropic hierarchy and some implications for Gaia theory. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Tangled Up in Views: Beliefs in the Nature of Science and Responses to Socio-Scientific Dilemmas.

    ERIC Educational Resources Information Center

    Zeidler, Dana L.; Walker, Kimberly A.; Ackett, Wayne A.; Simmons, Michael L.

    The purpose of this study was to investigate the relationships between students' conceptions of the nature of science and their reactions to evidence that challenged their beliefs about socio-scientific issues. This study used 248 students from 9th and 10th grade general science classes, 11th and 12th grade honors biology, honors science, and…

  12. Effect of ultramafic intrusions and associated mineralized rocks on the aqueous geochemistry of the Tangle Lakes Area, Alaska: Chapter C in Studies by the U.S. Geological Survey in Alaska, 2011

    USGS Publications Warehouse

    Wang, Bronwen; Gough, Larry P.; Wanty, Richard B.; Lee, Gregory K.; Vohden, James; O’Neill, J. Michael; Kerin, L. Jack

    2013-01-01

    Stream water was collected at 30 sites within the Tangle Lakes area of the Delta mineral belt in Alaska. Sampling focused on streams near the ultramafic rocks of the Fish Lake intrusive complex south of Eureka Creek and the Tangle Complex area east of Fourteen Mile Lake, as well as on those within the deformed metasedimentary, metavolcanic, and intrusive rocks of the Specimen Creek drainage and drainages east of Eureka Glacier. Major, minor, and trace elements were analyzed in aqueous samples for this reconnaissance aqueous geochemistry effort. The lithologic differences within the study area are reflected in the major-ion chemistry of the water. The dominant major cation in streams draining mafic and ultramafic rocks is Mg2+; abundant Mg and low Ca in these streams reflect the abundance of Mg-rich minerals in these intrusions. Nickel and Cu are detected in 84 percent and 87 percent of the filtered samples, respectively. Nickel and Cu concentrations ranged from Ni <0.4 to 10.1 micrograms per liter (mg/L), with a median of 4.2 mg/L, and Cu <0.5 to 27 mg/L, with a median of 1.2 mg/L. Trace-element concentrations in water are generally low relative to U.S. Environmental Protection Agency freshwater aquatic-life criteria; however, Cu concentrations exceed the hardness-based criteria for both chronic and acute exposure at some sites. The entire rare earth element (REE) suite is found in samples from the Specimen Creek sites MH5, MH4, and MH6 and, with the exception of Tb and Tm, at site MH14. These samples were all collected within drainages containing or downstream from Tertiary gabbro, diabase, and metagabbro (Trgb) exposures. Chondrite and source rock fractionation profiles for the aqueous samples were light rare earth element depleted, with negative Ce and Eu anomalies, indicating fractionation of the REE during weathering. Fractionation patterns indicate that the REE are primarily in the dissolved, as opposed to colloidal, phase.

  13. Modifiable Risk Factors and Brain Positron Emission Tomography Measures of Amyloid and Tau in Nondemented Adults with Memory Complaints.

    PubMed

    Merrill, David A; Siddarth, Prabha; Raji, Cyrus A; Emerson, Natacha D; Rueda, Florangel; Ercoli, Linda M; Miller, Karen J; Lavretsky, Helen; Harris, Laurel M; Burggren, Alison C; Bookheimer, Susan Y; Barrio, Jorge R; Small, Gary W

    2016-09-01

    Exercise and diet impact body composition, but their age-related brain effects are unclear at the molecular imaging level. To address these issues, the authors determined whether body mass index (BMI), physical activity, and diet relate to brain positron emission tomography (PET) of amyloid plaques and tau tangles using 2-(1-(6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl)ethylidene)malononitrile (FDDNP). Volunteers (N = 44; mean age: 62.6 ± 10.7 years) with subjective memory impairment (N = 24) or mild cognitive impairment (MCI; N = 20) were recruited by soliciting for memory complaints. Levels of physical activity and extent of following a Mediterranean-type diet were self-reported. FDDNP-PET scans assessed plaque/tangle binding in Alzheimer disease-associated regions (frontal, parietal, medial and lateral temporal, posterior cingulate). Mixed models controlling for known covariates examined BMI, physical activity, and diet in relation to FDDNP-PET. MCI subjects with above normal BMI (>25) had higher FDDNP-PET binding compared with those with normal BMI (1.11(0.03) versus 1.08(0.03), ES = 1.04, t(35) = 3.3, p = 0.002). Greater physical activity was associated with lower FDDNP-PET binding in MCI subjects (1.07(0.03) versus 1.11(0.03), ES = 1.13, t(35) = -3.1, p = 0.004) but not in subjects with subjective memory impairment (1.07(0.03) versus 1.07(0.03), ES = 0.02, t(35) = -0.1, p = 0.9). Healthier diet related to lower FDDNP-PET binding, regardless of cognitive status (1.07(0.03) versus 1.09(0.02), ES = 0.72, t(35) = -2.1, p = 0.04). These preliminary findings are consistent with a relationship between risk modifiersand brain plaque/tangle deposition in nondemented individuals and supports maintenance of normal body weight, regular physical activity, and healthy diet to protect the brain during aging. (clinicaltrials.gov; NCT00355498). Copyright © 2016 American Association for Geriatric Psychiatry. Published by Elsevier Inc. All rights reserved.

  14. Dynamically variable spot size laser system

    NASA Technical Reports Server (NTRS)

    Gradl, Paul R. (Inventor); Hurst, John F. (Inventor); Middleton, James R. (Inventor)

    2012-01-01

    A Dynamically Variable Spot Size (DVSS) laser system for bonding metal components includes an elongated housing containing a light entry aperture coupled to a laser beam transmission cable and a light exit aperture. A plurality of lenses contained within the housing focus a laser beam from the light entry aperture through the light exit aperture. The lenses may be dynamically adjusted to vary the spot size of the laser. A plurality of interoperable safety devices, including a manually depressible interlock switch, an internal proximity sensor, a remotely operated potentiometer, a remotely activated toggle and a power supply interlock, prevent activation of the laser and DVSS laser system if each safety device does not provide a closed circuit. The remotely operated potentiometer also provides continuous variability in laser energy output.

  15. 10 K gate I(2)L and 1 K component analog compatible bipolar VLSI technology - HIT-2

    NASA Astrophysics Data System (ADS)

    Washio, K.; Watanabe, T.; Okabe, T.; Horie, N.

    1985-02-01

    An advanced analog/digital bipolar VLSI technology that combines on the same chip 2-ns 10 K I(2)L gates with 1 K analog devices is proposed. The new technology, called high-density integration technology-2, is based on a new structure concept that consists of three major techniques: shallow grooved-isolation, I(2)L active layer etching, and I(2)L current gain increase. I(2)L circuits with 80-MHz maximum toggle frequency have developed compatibly with n-p-n transistors having a BV(CE0) of more than 10 V and an f(T) of 5 GHz, and lateral p-n-p transistors having an f(T) of 150 MHz.

  16. Integrated circuit test-port architecture and method and apparatus of test-port generation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Teifel, John

    A method and apparatus are provided for generating RTL code for a test-port interface of an integrated circuit. In an embodiment, a test-port table is provided as input data. A computer automatically parses the test-port table into data structures and analyzes it to determine input, output, local, and output-enable port names. The computer generates address-detect and test-enable logic constructed from combinational functions. The computer generates one-hot multiplexer logic for at least some of the output ports. The one-hot multiplexer logic for each port is generated so as to enable the port to toggle between data signals and test signals. Themore » computer then completes the generation of the RTL code.« less

  17. Tackling the Triple-Threat Genome of Miscanthus x giganteus (2010 JGI User Meeting)

    ScienceCinema

    Moose, Steve

    2018-02-05

    Steve Moose from the University of Illinois at Urbana-Champaign and the Energy Biosciences Institute on "Tackling the Triple-Threat Genome of Miscanthus x giganteus" on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

  18. Tackling the Triple-Threat Genome of Miscanthus x giganteus (2010 JGI User Meeting)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moose, Steve

    2010-03-25

    Steve Moose from the University of Illinois at Urbana-Champaign and the Energy Biosciences Institute on "Tackling the Triple-Threat Genome of Miscanthus x giganteus" on March 25, 2010 at the 5th Annual DOE JGI User Meeting.

  19. Association between community socioeconomic characteristics and access to youth flag football.

    PubMed

    Kroshus, Emily; Sonnen, Aly J; Chrisman, Sara Pd; Rivara, Frederick P

    2018-01-12

    The American Academy of Pediatrics has recommended that opportunities for non-tackling American football (e.g., flag football) be expanded, given concerns about the risks of brain trauma from tackle football. This study tested the hypothesis that flag football would be more accessible in communities characterised by higher socioeconomic status residents. In July 2017, the locations of community-based organisations offering youth flag and tackle football for youth between the ages of 6 and 13 in two US states (Georgia and Washington) were aggregated (n=440). Organisations were coded in terms of the availability of tackle and/or flag football teams for youth at each year of age between 6 and 13. Multivariate logistic regression analyses were used to assess the odds of a community-based football organisation offering flag football, by community socioeconomic and demographic characteristics. In both states, communities with more educated residents were more likely to offer flag football for youth aged 6-12. For example, among 6 year-olds every 10% increase in the number of adult residents with a college education was associated with 1.51 times the odds of flag football availability (95% CI 1.22 to 1.86, P<0.001). These results suggest that youth living in communities characterised by low educational attainment are less likely than other youth to have the option of a lower contact alternative to tackle football. Relying on voluntary community-level adoption of lower contact alternatives to tackle football may result in inequitable access to such sport options. This may contribute to an inequitable burden of brain trauma from youth sport. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  20. Tackling racism in the NHS.

    PubMed

    Dean, Erin

    2016-11-30

    Essential facts Trade union Unite has developed a policy briefing on a new toolkit to combat racism in the NHS. It can help nurses and other staff tackle racial discrimination in health, with black and minority ethnic (BME) nurses often treated unequally compared with their white colleagues.

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