DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Dong-Yang; Wen, Jing-Ji; Bai, Cheng-Hua
2015-09-15
An effective scheme is proposed to generate the singlet state with three four-level atoms trapped in three distant cavities connected with each other by three optical fibers, respectively. After a series of appropriate atom–cavity interactions, which can be arbitrarily controlled via the selective pairing of Raman transitions and corresponding optical switches, a three-atom singlet state can be successfully generated. The influence of atomic spontaneous decay, photon leakage of cavities and optical fibers on the fidelity of the state is numerically simulated showing that the three-atom singlet state can be generated with high fidelity by choosing the experimental parameters appropriately.
Shunts to divert aqueous humor to distant epithelialized cavities after keratoprosthesis surgery.
Dohlman, Claes H; Grosskreutz, Cynthia L; Chen, Teresa C; Pasquale, Louis R; Rubin, Peter A D; Kim, Eva C; Durand, Marlene
2010-02-01
Glaucoma is a frequent and often severe problem in patients needing keratoprosthesis (KPro) surgery. Standard glaucoma shunts in these cases often develop a very dense capsule that obstructs flow and causes intraocular pressure elevation. Therefore, we developed shunts that deliver aqueous to distant epithelialized cavities where an obstructing capsule is less likely to form. In this retroactive study of such shunts, the risk of postoperative infection (especially endophthalmitis) has been assessed. Ahmed shunts were connected with a tube to the lacrimal sac or ethmoid sinuses. In subsequent designs the polypropylene plate was eliminated, the valve was enclosed and a distal tube added (New World Medical Inc, Rancho Cucamonga, CA). The latter shunts were connected to the maxillary sinus or lower lid fornix. Between 2001 and 2005 the devices were implanted in 34 patients with very severe ocular disease. (31 had KPro implanted). Thus, the distal tube was led to the lacrimal sac (2 cases), to the ethmoid sinuses (6), to the maxillary sinus (16 cases), and to the lower lid fornix (10 cases). The patients were followed for cumulatively 145 shunt years, with a mean follow-up of 4 years and 3 months. They were instructed to administer low-dose topical antibiotics indefinitely. Only 1 case of acute bacterial endophthalmitis occurred, thus an incidence of 0.7% per shunt year. A slow-growing Mycobacterium was cultured in a disintegrating eye and 1 bacterial maxillary sinusitis occurred, both in autoimmune diseases. Three valves became exposed and had to be removed (1 replaced). Four eyes developed hypotony, probably from valve failure. The shunt arrangement, which connects the anterior chamber to potentially microbe-populated cavities or to the lower lid fornix and its flora, might be suspected to allow rapid retrograde invasion of infective agents, resulting in endophthalmitis. In this series of KPro patients, however, the incidence of severe infection was very low, in fact comparable to that after standard trabeculectomy.
Cavity Mediated Manipulation of Distant Spin Currents Using a Cavity-Magnon-Polariton.
Bai, Lihui; Harder, Michael; Hyde, Paul; Zhang, Zhaohui; Hu, Can-Ming; Chen, Y P; Xiao, John Q
2017-05-26
Using electrical detection of a strongly coupled spin-photon system comprised of a microwave cavity mode and two magnetic samples, we demonstrate the long distance manipulation of spin currents. This distant control is not limited by the spin diffusion length, instead depending on the interplay between the local and global properties of the coupled system, enabling systematic spin current control over large distance scales (several centimeters in this work). This flexibility opens the door to improved spin current generation and manipulation for cavity spintronic devices.
Driving many distant atoms into high-fidelity steady state entanglement via Lyapunov control.
Li, Chuang; Song, Jie; Xia, Yan; Ding, Weiqiang
2018-01-22
Based on Lyapunov control theory in closed and open systems, we propose a scheme to generate W state of many distant atoms in the cavity-fiber-cavity system. In the closed system, the W state is generated successfully even when the coupling strength between the cavity and fiber is extremely weak. In the presence of atomic spontaneous emission or cavity and fiber decay, the photon-measurement and quantum feedback approaches are proposed to improve the fidelity, which enable efficient generation of high-fidelity W state in the case of large dissipation. Furthermore, the time-optimal Lyapunov control is investigated to shorten the evolution time and improve the fidelity in open systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kang, Chung-Jan; Head and Neck Oncology Group, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan; Lin, Chien-Yu
2011-11-15
Purpose: The objective of this retrospective study was twofold: (1) to investigate prognostic factors for clinical outcomes in patients with poorly differentiated oral cavity squamous cell carcinoma and (2) to identify specific prognostic subgroups that may help to guide treatment decisions. Methods and Materials: We examined 102 patients with poorly differentiated oral cavity squamous cell carcinoma. All patients were followed for at least 24 months after surgery or until death. The 5-year rates of local control, neck control, distant metastasis, disease-free, disease-specific, and overall survival served as main outcome measures. Results: The 5-year rates were as follows: local control (79%),more » neck control (64%), distant metastases (27%), disease-free survival (48%), disease-specific survival (52%), and overall survival (42%). Multivariable analysis showed that the number of pathologically positive nodes ({>=}4 vs. {<=}3) was a significant predictor of neck control, distant metastasis, and disease-free, disease-specific, and overall survival rates. In addition, the presence of tumor depth of {>=}11 mm (vs. <11 mm) was a significant predictor of distant metastasis, disease-specific survival, and overall survival rates. The combination of the two predictors (26.5%, 27/102) was independently associated with poorer neck control (p = 0.0319), distant metastasis (p < 0.0001), and disease-free (p < 0.0001), disease-specific (p < 0.0001), and overall survival (p < 0.0001) rates. Conclusions: In patients with poorly differentiated oral cavity squamous cell carcinoma, the presence of at least 4 pathologically positive lymph nodes and of a pathological tumor depth {>=}11 mm identifies a subset of subjects with poor clinical outcomes. Patients carrying both risk factors are suitable candidates for the development of novel therapeutic approaches.« less
Remote entanglement stabilization for modular quantum computing
NASA Astrophysics Data System (ADS)
Didier, Nicolas; Shankar, S.; Mirrahimi, M.
Quantum information processing in a modular architecture requires to distribute and stabilize entanglement in a qubit network. We present autonomous entanglement stabilization protocols between two qubits that are coupled to distant cavities. The cavities coupling is mediated and controlled via a three-wave mixing device that generates either a delocalized mode or a two-mode squeezed state between the remote cavities depending on the pump frequency. Local drives on the qubits and the cavities steer and maintain the system to the desired qubit Bell state. We show that these reservoir-engineering based protocols stabilize entanglement in presence of qubit-cavity asymmetries and losses. Most spectacularly, even a weakly-squeezed state can stabilize a maximally entangled Bell state of two distant qubits through entanglement accumulation. This research was supported by the Agence Nationale de la Recherche under Grant ANR-14-CE26-0018, by Inria's DPEI under the TAQUILLA associated team and by ARO under Grant No. W911NF-14-1-0011.
Li, Chuang; Yang, Sen; Song, Jie; Xia, Yan; Ding, Weiqiang
2017-05-15
In this paper, a scheme for the generation of long-living entanglement between two distant Λ-type three-level atoms separately trapped in two dissipative cavities is proposed. In this scheme, two dissipative cavities are coupled to their own non-Markovian environments and two three-level atoms are driven by the classical fields. The entangled state between the two atoms is produced by performing Bell state measurement (BSM) on photons leaving the dissipative cavities. Using the time-dependent Schördinger equation, we obtain the analytical results for the evolution of the entanglement. It is revealed that, by manipulating the detunings of classical field, the long-living stationary entanglement between two atoms can be generated in the presence of dissipation.
Deterministic quantum state transfer between remote qubits in cavities
NASA Astrophysics Data System (ADS)
Vogell, B.; Vermersch, B.; Northup, T. E.; Lanyon, B. P.; Muschik, C. A.
2017-12-01
Performing a faithful transfer of an unknown quantum state is a key challenge for enabling quantum networks. The realization of networks with a small number of quantum links is now actively pursued, which calls for an assessment of different state transfer methods to guide future design decisions. Here, we theoretically investigate quantum state transfer between two distant qubits, each in a cavity, connected by a waveguide, e.g., an optical fiber. We evaluate the achievable success probabilities of state transfer for two different protocols: standard wave packet shaping and adiabatic passage. The main loss sources are transmission losses in the waveguide and absorption losses in the cavities. While special cases studied in the literature indicate that adiabatic passages may be beneficial in this context, it remained an open question under which conditions this is the case and whether their use will be advantageous in practice. We answer these questions by providing a full analysis, showing that state transfer by adiabatic passage—in contrast to wave packet shaping—can mitigate the effects of undesired cavity losses, far beyond the regime of coupling to a single waveguide mode and the regime of lossless waveguides, as was proposed so far. Furthermore, we show that the photon arrival probability is in fact bounded in a trade-off between losses due to non-adiabaticity and due to coupling to off-resonant waveguide modes. We clarify that neither protocol can avoid transmission losses and discuss how the cavity parameters should be chosen to achieve an optimal state transfer.
Cancer Salivary Biomarkers for Tumours Distant to the Oral Cavity
Rapado-González, Óscar; Majem, Blanca; Muinelo-Romay, Laura; López-López, Rafa; Suarez-Cunqueiro, María Mercedes
2016-01-01
The analysis of saliva as a diagnostic approach for systemic diseases was proposed just two decades ago, but recently great interest in the field has emerged because of its revolutionary potential as a liquid biopsy and its usefulness as a non-invasive sampling method. Multiple molecules isolated in saliva have been proposed as cancer biomarkers for diagnosis, prognosis, drug monitoring and pharmacogenetic studies. In this review, we focus on the current status of the salivary diagnostic biomarkers for different cancers distant to the oral cavity, noting their potential use in the clinic and their applicability in personalising cancer therapies. PMID:27626410
Davy, John L
2012-08-01
The author has published equations for predicting the air borne sound transmission of double leaf cavity walls due to the structure borne sound transmission across the air cavity via (possibly resilient) line connections, but has never published the full derivation of these equations. The author also derived equations for the case when the connections are rigid point connections but has never used them or published them or their derivations. This paper will present the full derivation of the author's theory of the air borne sound transmission of double leaf cavity walls due to the structure borne sound transmission across the air cavity via point or line connections which are modeled as four pole networks. The theoretical results will be compared with experimental results on wooden stud cavity walls from the National Research Council of Canada because the screw spacing is given for these results. This enables connections via studs and screws to be modeled as point connections and avoids the need to make any assumptions about the compliance of the equivalent point or line connections.
Epicenters of dynamic connectivity in the adaptation of the ventral visual system.
Prčkovska, Vesna; Huijbers, Willem; Schultz, Aaron; Ortiz-Teran, Laura; Peña-Gomez, Cleofe; Villoslada, Pablo; Johnson, Keith; Sperling, Reisa; Sepulcre, Jorge
2017-04-01
Neuronal responses adapt to familiar and repeated sensory stimuli. Enhanced synchrony across wide brain systems has been postulated as a potential mechanism for this adaptation phenomenon. Here, we used recently developed graph theory methods to investigate hidden connectivity features of dynamic synchrony changes during a visual repetition paradigm. Particularly, we focused on strength connectivity changes occurring at local and distant brain neighborhoods. We found that connectivity reorganization in visual modal cortex-such as local suppressed connectivity in primary visual areas and distant suppressed connectivity in fusiform areas-is accompanied by enhanced local and distant connectivity in higher cognitive processing areas in multimodal and association cortex. Moreover, we found a shift of the dynamic functional connections from primary-visual-fusiform to primary-multimodal/association cortex. These findings suggest that repetition-suppression is made possible by reorganization of functional connectivity that enables communication between low- and high-order areas. Hum Brain Mapp 38:1965-1976, 2017. © 2017 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Qin, Wei; Wang, Xin; Miranowicz, Adam; Zhong, Zhirong; Nori, Franco
2017-07-01
Heralded near-deterministic multiqubit controlled-phase gates with integrated error detection have recently been proposed by Borregaard et al. [Phys. Rev. Lett. 114, 110502 (2015), 10.1103/PhysRevLett.114.110502]. This protocol is based on a single four-level atom (a heralding quartit) and N three-level atoms (operational qutrits) coupled to a single-resonator mode acting as a cavity bus. Here we generalize this method for two distant resonators without the cavity bus between the heralding and operational atoms. Specifically, we analyze the two-qubit controlled-Z gate and its multiqubit-controlled generalization (i.e., a Toffoli-like gate) acting on the two-lowest levels of N qutrits inside one resonator, with their successful actions being heralded by an auxiliary microwave-driven quartit inside the other resonator. Moreover, we propose a circuit-quantum-electrodynamics realization of the protocol with flux and phase qudits in linearly coupled transmission-line resonators with dissipation. These methods offer a quadratic fidelity improvement compared to cavity-assisted deterministic gates.
Cavity-Mediated Coherent Coupling between Distant Quantum Dots
NASA Astrophysics Data System (ADS)
Nicolí, Giorgio; Ferguson, Michael Sven; Rössler, Clemens; Wolfertz, Alexander; Blatter, Gianni; Ihn, Thomas; Ensslin, Klaus; Reichl, Christian; Wegscheider, Werner; Zilberberg, Oded
2018-06-01
Scalable architectures for quantum information technologies require one to selectively couple long-distance qubits while suppressing environmental noise and cross talk. In semiconductor materials, the coherent coupling of a single spin on a quantum dot to a cavity hosting fermionic modes offers a new solution to this technological challenge. Here, we demonstrate coherent coupling between two spatially separated quantum dots using an electronic cavity design that takes advantage of whispering-gallery modes in a two-dimensional electron gas. The cavity-mediated, long-distance coupling effectively minimizes undesirable direct cross talk between the dots and defines a scalable architecture for all-electronic semiconductor-based quantum information processing.
Quantum non-demolition detection of an itinerant microwave photon
NASA Astrophysics Data System (ADS)
Kono, S.; Koshino, K.; Tabuchi, Y.; Noguchi, A.; Nakamura, Y.
2018-06-01
Photon detectors are an elementary tool to measure electromagnetic waves at the quantum limit1,2 and are heavily demanded in the emerging quantum technologies such as communication3, sensing4 and computing5. Of particular interest is a quantum non-demolition (QND)-type detector, which projects an electromagnetic wave onto the photon-number basis6-10. This is in stark contrast to conventional photon detectors2 that absorb a photon to trigger a `click'. The long-sought QND detection of a flying photon was recently demonstrated in the optical domain using a single atom in a cavity11,12. However, the counterpart for microwaves has been elusive despite the recent progress in microwave quantum optics using superconducting circuits13-19. Here, we implement a deterministic entangling gate between a superconducting qubit and an itinerant microwave photon reflected by a cavity containing the qubit. Using the entanglement and the high-fidelity qubit readout, we demonstrate a QND detection of a single photon with the quantum efficiency of 0.84 and the photon survival probability of 0.87. Our scheme can serve as a building block for quantum networks connecting distant qubit modules as well as a microwave-photon-counting device for multiple-photon signals.
NASA Astrophysics Data System (ADS)
Veiga, José P.; Wamiti, Wanyoike; Polo, Vicente; Muchai, Muchane
2013-09-01
Although competition is usually assumed to be the most common interaction between closely related organisms that share limiting resources, the relationships linking distant taxa that use the same nesting sites are poorly understood. In the present study, we examine the interactions among social hymenopterans (honeybees and wasps) and vertebrates in tropical ecosystems of East Africa. By analysing the preferences of these three groups for nest boxes that were empty or previously occupied by a different taxon, we try to establish whether the relationships among them are commensal, mutualistic, competitive or amensal. Vertebrates and honeybees selected nest boxes that had previously been occupied by the other, which suggests that each obtains some benefit from the other. This relationship can be considered mutualistic, although a mutual preference for each others' nests does not exclude a competitive interaction. Vertebrates and wasps preferred nest boxes not previously occupied by the other, which suggests that they compete for tree cavities. Finally, wasps seemed to completely refuse cavities previously used by honeybees, while the bees occupied cavities regardless of whether they had been previously used by wasps, an apparently amensal relationship. These results indicate that the interdependence between distantly related taxa is stronger and more complex than previously described, which may have important implications for population dynamics and community structure.
Method and apparatus for varying accelerator beam output energy
Young, Lloyd M.
1998-01-01
A coupled cavity accelerator (CCA) accelerates a charged particle beam with rf energy from a rf source. An input accelerating cavity receives the charged particle beam and an output accelerating cavity outputs the charged particle beam at an increased energy. Intermediate accelerating cavities connect the input and the output accelerating cavities to accelerate the charged particle beam. A plurality of tunable coupling cavities are arranged so that each one of the tunable coupling cavities respectively connect an adjacent pair of the input, output, and intermediate accelerating cavities to transfer the rf energy along the accelerating cavities. An output tunable coupling cavity can be detuned to variably change the phase of the rf energy reflected from the output coupling cavity so that regions of the accelerator can be selectively turned off when one of the intermediate tunable coupling cavities is also detuned.
Marcos-Vidal, Luis; Martínez-García, Magdalena; Pretus, Clara; Garcia-Garcia, David; Martínez, Kenia; Janssen, Joost; Vilarroya, Oscar; Castellanos, Francisco X; Desco, Manuel; Sepulcre, Jorge; Carmona, Susanna
2018-06-01
Previous studies have associated Attention-Deficit/Hyperactivity Disorder (ADHD) with a maturational lag of brain functional networks. Functional connectivity of the human brain changes from primarily local to more distant connectivity patterns during typical development. Under the maturational lag hypothesis, we expect children with ADHD to exhibit increased local connectivity and decreased distant connectivity compared with neurotypically developing (ND) children. We applied a graph-theory method to compute local and distant connectivity levels and cross-sectionally compared them in a sample of 120 children with ADHD and 120 age-matched ND children (age range = 7-17 years). In addition, we measured if potential group differences in local and distant connectivity were stable across the age range considered. Finally, we assessed the clinical relevance of observed group differences by correlating the connectivity levels and ADHD symptoms severity separately for each group. Children with ADHD exhibited more local connectivity than age-matched ND children in multiple brain regions, mainly overlapping with default mode, fronto-parietal and ventral attentional functional networks (p < .05- threshold free-cluster enhancement-family-wise error). We detected an atypical developmental pattern of local connectivity in somatomotor regions, that is, decreases with age in ND children, and increases with age in children with ADHD. Furthermore, local connectivity within somatomotor areas correlated positively with clinical severity of ADHD symptoms, both in ADHD and ND children. Results suggest an immature functional state of multiple brain networks in children with ADHD. Whereas the ADHD diagnosis is associated with the integrity of the system comprising the fronto-parietal, default mode and ventral attentional networks, the severity of clinical symptoms is related to atypical functional connectivity within somatomotor areas. Additionally, our findings are in line with the view of ADHD as a disorder of deviated maturational trajectories, mainly affecting somatomotor areas, rather than delays that normalize with age. © 2018 Wiley Periodicals, Inc.
Integrated circuit cooled turbine blade
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Ching-Pang; Jiang, Nan; Um, Jae Y.
A turbine rotor blade includes at least two integrated cooling circuits that are formed within the blade that include a leading edge circuit having a first cavity and a second cavity and a trailing edge circuit that includes at least a third cavity located aft of the second cavity. The trailing edge circuit flows aft with at least two substantially 180-degree turns at the tip end and the root end of the blade providing at least a penultimate cavity and a last cavity. The last cavity is located along a trailing edge of the blade. A tip axial cooling channelmore » connects to the first cavity of the leading edge circuit and the penultimate cavity of the trailing edge circuit. At least one crossover hole connects the penultimate cavity to the last cavity substantially near the tip end of the blade.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Minniti, Giuseppe, E-mail: gminniti@ospedalesantandrea.it; Department of Neurological Sciences, Scientific Institute IRCCS Neuromed, Pozzilli; Esposito, Vincenzo
2013-07-15
Purpose: To evaluate the clinical outcomes with linear accelerator-based multidose stereotactic radiosurgery (SRS) to large postoperative resection cavities in patients with large brain metastases. Methods and Materials: Between March 2005 to May 2012, 101 patients with a single brain metastasis were treated with surgery and multidose SRS (9 Gy × 3) for large resection cavities (>3 cm). The target volume was the resection cavity with the inclusion of a 2-mm margin. The median cavity volume was 17.5 cm{sup 3} (range, 12.6-35.7 cm{sup 3}). The primary endpoint was local control. Secondary endpoints were survival and distant failure rates, cause of death,more » performance measurements, and toxicity of treatment. Results: With a median follow-up of 16 months (range, 6-44 months), the 1-year and 2-year actuarial survival rates were 69% and 34%, respectively. The 1-year and 2-year local control rates were 93% and 84%, with respective incidences of new distant brain metastases of 50% and 66%. Local control was similar for radiosensitive (non-small cell lung cancer and breast cancer) and radioresistant (melanoma and renal cell cancer) brain metastases. On multivariate Cox analysis stable extracranial disease, breast cancer histology, and Karnofsky performance status >70 were associated with significant survival benefit. Brain radionecrosis occurred in 9 patients (9%), being symptomatic in 5 patients (5%). Conclusions: Adjuvant multidose SRS to resection cavity represents an effective treatment option that achieves excellent local control and defers the use of whole-brain radiation therapy in selected patients with large brain metastases.« less
NASA Astrophysics Data System (ADS)
Gong, Z. R.; Ian, H.; Zhou, Lan; Sun, C. P.
2008-11-01
We study the coherent scattering process of a single photon confined in an one-dimensional (1D) coupled cavity-array, where a Λ -type three-level atom is placed inside one of the cavities in the array and behaves as a functional quantum node (FQN). We show that, through the electromagnetically-induced-transparency mechanism, the Λ -type FQN bears complete control over the reflection and transmission of the incident photon along the cavity array. We also demonstrate the emergence of a quasibound state of the single photon inside a secondary cavity constructed by two distant FQN’s as two end mirrors, from which we are motivated to design an all-optical single photon storage device of quantum coherence.
Hua, Ming; Tao, Ming-Jie; Deng, Fu-Guo; Lu Long, Gui
2015-01-01
We propose a scheme to construct the controlled-phase (c-phase) gate on distant transmon qutrits hosted in different resonators inter-coupled by a connected transmon qutrit. Different from previous works for entanglement generation and information transfer on two distant qubits in a dispersive regime in the similar systems, our gate is constructed in the resonant regime with one step. The numerical simulation shows that the fidelity of our c-phase gate is 99.5% within 86.3 ns. As an interesting application of our c-phase gate, we propose an effective scheme to complete a conventional square lattice of two-dimensional surface code layout for fault-tolerant quantum computing on the distant transmon qutrits. The four-step coupling between the nearest distant transmon qutrits, small coupling strengths of the distant transmon qutrits, and the non-population on the connection transmon qutrit can reduce the interactions among different parts of the layout effectively, which makes the layout be integrated with a large scale in an easier way. PMID:26486426
Beucke, Jan C; Sepulcre, Jorge; Buhlmann, Ulrike; Kathmann, Norbert; Moody, Teena; Feusner, Jamie D
2016-10-01
Individuals with body dysmorphic disorder (BDD) and obsessive-compulsive disorder (OCD) are categorized within the same major diagnostic group and both show regional brain hyperactivity in the orbitofrontal cortex (OFC) and the basal ganglia during symptom provocation. While recent studies revealed that degree connectivity of these areas is abnormally high in OCD and positively correlates with symptom severity, no study has investigated degree connectivity in BDD. We used functional magnetic resonance imaging (fMRI) to compare the local and distant degree of functional connectivity in all brain areas between 28 unmedicated BDD participants and 28 demographically matched healthy controls during a face-processing task. Correlational analyses tested for associations between degree connectivity and symptom severity assessed by the BDD version of the Yale-Brown obsessive-compulsive scale (BDD-Y-BOCS). Reduced local amygdalar connectivity was found in participants with BDD. No differences in distant connectivity were found. BDD-Y-BOCS scores significantly correlated with the local connectivity of the posterior-lateral OFC, and distant connectivity of the posterior-lateral and post-central OFC, respectively. These findings represent preliminary evidence that individuals with BDD exhibit brain-behavioral associations related to obsessive thoughts and compulsive behaviors that are highly similar to correlations previously found in OCD, further underscoring their related pathophysiology. This relationship could be further elucidated through investigation of resting-state functional connectivity in BDD, ideally in direct comparison with OCD and other obsessive-compulsive and related disorders. Copyright © 2016 Elsevier B.V. and ECNP. All rights reserved.
Effective optical path length for tandem diffuse cubic cavities as gas absorption cell
NASA Astrophysics Data System (ADS)
Yu, J.; Gao, Q.; Zhang, Y. G.; Zhang, Z. G.; Wu, S. H.
2014-12-01
Tandem diffuse cubic cavities designed by connecting two single diffuse cubic-shaped cavities, A and B, with an aperture (port fraction fap) in the middle of the connecting baffle was developed as a gas absorption cell. The effective optical path length (EOPL) was evaluated by comparing the oxygen absorption signal in the cavity and in air based on tunable diode laser absorption spectroscopy (TDLAS). Experimental results manifested an enhancement of EOPL for the tandem diffuse cubic cavities as the decrease of fap and can be expressed as the sum of EOPL of two single cubic cavities at fap < 0.01, which coincided well with theoretical analysis. The simulating EOPL was smaller than experimental results at fap > 0.01, which indicated that back scattering light from cavity B to cavity A cannot be ignored at this condition.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fang Baolong; Department of Mathematics and Physics, Hefei University, Hefei, 230022; Song Qingming
We present a scheme to realize a special quantum cloning machine in separate cavities. The quantum cloning machine can copy the quantum information from a photon pulse to two distant atoms. Choosing the different parameters, the method can perform optimal symmetric (asymmetric) universal quantum cloning and optimal symmetric (asymmetric) phase-covariant cloning.
Quantum State Transfer via Noisy Photonic and Phononic Waveguides
NASA Astrophysics Data System (ADS)
Vermersch, B.; Guimond, P.-O.; Pichler, H.; Zoller, P.
2017-03-01
We describe a quantum state transfer protocol, where a quantum state of photons stored in a first cavity can be faithfully transferred to a second distant cavity via an infinite 1D waveguide, while being immune to arbitrary noise (e.g., thermal noise) injected into the waveguide. We extend the model and protocol to a cavity QED setup, where atomic ensembles, or single atoms representing quantum memory, are coupled to a cavity mode. We present a detailed study of sensitivity to imperfections, and apply a quantum error correction protocol to account for random losses (or additions) of photons in the waveguide. Our numerical analysis is enabled by matrix product state techniques to simulate the complete quantum circuit, which we generalize to include thermal input fields. Our discussion applies both to photonic and phononic quantum networks.
Oral Microbiome: A New Biomarker Reservoir for Oral and Oropharyngeal Cancers
Lim, Yenkai; Totsika, Makrina; Morrison, Mark; Punyadeera, Chamindie
2017-01-01
Current biomarkers (DNA, RNA and protein) for oral cavity and oropharyngeal cancers demonstrate biological variations between individuals, rendering them impractical for clinical translation. Whilst these biomarkers originate from the host, there is not much information in the literature about the influence of oral microbiota on cancer pathogenesis, especially in oral cancers. Oral microbiotas are known to participate in disease initiation and progression not only limited to the oral cavity, but also at other distant sites. Due to the close proximity of oral microbiota and oral cavity and oropharyngeal tumours, abundance changes in oral microbiota may provide useful information on tumourigenesis. This review aims to highlight information on the role of oral microbiota in oral cavity and oropharyngeal cancers. An in-depth analysis into the oral microbiota may provide a new avenue to diagnose and treat these patients. PMID:29158828
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aceves, Salvador M.; Ledesma-Orozco, Elias Rigoberto; Espinosa-Loza, Francisco
A pressure vessel apparatus for cryogenic capable storage of hydrogen or other cryogenic gases at high pressure includes an insert with a parallel inlet duct, a perpendicular inlet duct connected to the parallel inlet. The perpendicular inlet duct and the parallel inlet duct connect the interior cavity with the external components. The insert also includes a parallel outlet duct and a perpendicular outlet duct connected to the parallel outlet duct. The perpendicular outlet duct and the parallel outlet duct connect the interior cavity with the external components.
Undercut feature recognition for core and cavity generation
NASA Astrophysics Data System (ADS)
Yusof, Mursyidah Md; Salman Abu Mansor, Mohd
2018-01-01
Core and cavity is one of the important components in injection mould where the quality of the final product is mostly dependent on it. In the industry, with years of experience and skill, mould designers commonly use commercial CAD software to design the core and cavity which is time consuming. This paper proposes an algorithm that detect possible undercut features and generate the core and cavity. Two approaches are presented; edge convexity and face connectivity approach. The edge convexity approach is used to recognize undercut features while face connectivity is used to divide the faces into top and bottom region.
Apparatus for connecting aligned abutted tubes
Williams, R.E.
1984-11-29
An apparatus for connecting abutted tubes and for maintaining their rotary alignment during connection. The apparatus comprises first and second tubes, a rotation prevention element, a collar and a retainer. Each tube has inside and outside walls, and first and second ends, each end having an inside and outside edge. The first tube has portions defining a first plurality of cavities located at the outside edge of its first end. An external threaded portion is on the outside wall of the first tube and next to the first plurality of cavities. The second tube has portions defining a second plurality of cavities located at the outside edge of its first end. The first plurality has a different number than the second plurality. The first ends of the first and second tubes have substantially the same outside diameter and are abutted during connection so that an orifice is formed whenever first and second tube cavities substantially overlap. A rotation prevension element is placed in the orifice to prevent rotation of the first and second tubes. A collar with an internal threaded portion is slidably disposed about the second tube. The internal threaded portion engages the external threaded portion of the first tube to connect the tubes. A lip connected to the collar prevents separation of the collar from the second tube.
Measurement of electrodynamics characteristics of higher order modes for harmonic cavity at 2400 MHz
NASA Astrophysics Data System (ADS)
Shashkov, Ya V.; Sobenin, N. P.; Gusarova, M. A.; Lalayan, M. V.; Bazyl, D. S.; Donetskiy, R. V.; Orlov, A. I.; Zobov, M. M.; Zavadtsev, A. A.
2016-09-01
In the frameworks of the High Luminosity Large Hadron Collider (HL-LHC) upgrade program an application of additional superconducting harmonic cavities operating at 800 MHz is currently under discussion. As a possible candidate, an assembly of two cavities with grooved beam pipes connected by a drift tube and housed in a common cryomodule, was proposed. In this article we discuss measurements of loaded Q-factors of higher order modes (HOM) performed on a scaled aluminium single cell cavity prototype with the fundamental frequency of 2400 MHz and on an array of two such cavities connected by a narrow beam pipe. The measurements were performed for the system with and without the matching load in the drift tube..
Modular Apparatus and Method for Attaching Multiple Devices
NASA Technical Reports Server (NTRS)
Okojie, Robert S (Inventor)
2015-01-01
A modular apparatus for attaching sensors and electronics is disclosed. The modular apparatus includes a square recess including a plurality of cavities and a reference cavity such that a pressure sensor can be connected to the modular apparatus. The modular apparatus also includes at least one voltage input hole and at least one voltage output hole operably connected to each of the plurality of cavities such that voltage can be applied to the pressure sensor and received from the pressure sensor.
Efficient teleportation between remote single-atom quantum memories.
Nölleke, Christian; Neuzner, Andreas; Reiserer, Andreas; Hahn, Carolin; Rempe, Gerhard; Ritter, Stephan
2013-04-05
We demonstrate teleportation of quantum bits between two single atoms in distant laboratories. Using a time-resolved photonic Bell-state measurement, we achieve a teleportation fidelity of (88.0 ± 1.5)%, largely determined by our entanglement fidelity. The low photon collection efficiency in free space is overcome by trapping each atom in an optical cavity. The resulting success probability of 0.1% is almost 5 orders of magnitude larger than in previous experiments with remote material qubits. It is mainly limited by photon propagation and detection losses and can be enhanced with a cavity-based deterministic Bell-state measurement.
A DISTANT ECHO OF MILKY WAY CENTRAL ACTIVITY CLOSES THE GALAXY’s BARYON CENSUS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nicastro, F.; Senatore, F.; Krongold, Y.
2016-09-01
We report on the presence of large amounts of million-degree gas in the Milky Way’s interstellar and circum-galactic medium. This gas (1) permeates both the Galactic plane and the halo, (2) extends to distances larger than 60–200 kpc from the center, and (3) its mass is sufficient to close the Galaxy’s baryon census. Moreover, we show that a vast, ∼6 kpc radius, spherically symmetric central region of the Milky Way above and below the 0.16 kpc thick plane has either been emptied of hot gas or the density of this gas within the cavity has a peculiar profile, increasing frommore » the center up to a radius of ∼6 kpc, and then decreasing with a typical halo density profile. This, and several other converging pieces of evidence, suggest that the current surface of the cavity, at 6 kpc from the Galaxy’s center, traces the distant echo of a period of strong nuclear activity of our supermassive black hole, occurring about 6 Myr ago.« less
Functional connectivity in the developing brain: A longitudinal study from 4 to 9 months of age
Damaraju, E.; Caprihan, A.; Lowe, J.R.; Allen, E.A.; Calhoun, V.D.; Phillips, J.P.
2013-01-01
We characterize the development of intrinsic connectivity networks (ICNs) from 4 to 9 months of age with resting state magnetic resonance imaging performed on sleeping infants without sedative medication. Data is analyzed with independent component analysis (ICA). Using both low (30 components) and high (100 components) ICA model order decompositions, we find that the functional network connectivity (FNC) map is largely similar at both 4 and 9 months. However at 9 months the connectivity strength decreases within local networks and increases between more distant networks. The connectivity within the default-mode network, which contains both local and more distant nodes, also increases in strength with age. The low frequency power spectrum increases with age only in the posterior cingulate cortex and posterior default mode network. These findings are consistent with a general developmental pattern of increasing longer distance functional connectivity over the first year of life and raise questions regarding the developmental importance of the posterior cingulate at this age. PMID:23994454
Functional connectivity in the developing brain: a longitudinal study from 4 to 9months of age.
Damaraju, E; Caprihan, A; Lowe, J R; Allen, E A; Calhoun, V D; Phillips, J P
2014-01-01
We characterize the development of intrinsic connectivity networks (ICNs) from 4 to 9months of age with resting state magnetic resonance imaging performed on sleeping infants without sedative medication. Data is analyzed with independent component analysis (ICA). Using both low (30 components) and high (100 components) ICA model order decompositions, we find that the functional network connectivity (FNC) map is largely similar at both 4 and 9months. However at 9months the connectivity strength decreases within local networks and increases between more distant networks. The connectivity within the default-mode network, which contains both local and more distant nodes, also increases in strength with age. The low frequency power spectrum increases with age only in the posterior cingulate cortex and posterior default mode network. These findings are consistent with a general developmental pattern of increasing longer distance functional connectivity over the first year of life and raise questions regarding the developmental importance of the posterior cingulate at this age. © 2013.
Vacuum holding fixture and method for fabricating piezoelectric polymer acoustic sensors
NASA Technical Reports Server (NTRS)
Hall, E. Thomas, Jr. (Inventor); Bryant, Timothy D. (Inventor)
1994-01-01
An apparatus and method for bonding a first film to a second film to form a sensor. The first and second films are piezoelectric films. A base section has a mating surface for holding the first film. A top section has a mating surface for holding the second film, the top section and base section being mateable together to form a cavity between the top section mating surface and the base section mating surface with the first film and the second film pressed together inside the cavity to bond the first film to the second film. An internal connection port forming mechanism forms an internal connection port between the first film and the second film when the base section and top section are mated together with the first film and the second film pressed together inside the cavity. Alternately, an internal connection tab forming mechanism can be used to form a sensor having an internal connection tab between the first and second film, instead of having an internal connection port.
High-density percutaneous chronic connector for neural prosthetics
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shah, Kedar G.; Bennett, William J.; Pannu, Satinderpall S.
2015-09-22
A high density percutaneous chronic connector, having first and second connector structures each having an array of magnets surrounding a mounting cavity. A first electrical feedthrough array is seated in the mounting cavity of the first connector structure and a second electrical feedthrough array is seated in the mounting cavity of the second connector structure, with a feedthrough interconnect matrix positioned between a top side of the first electrical feedthrough array and a bottom side of the second electrical feedthrough array to electrically connect the first electrical feedthrough array to the second electrical feedthrough array. The two arrays of magnetsmore » are arranged to attract in a first angular position which connects the first and second connector structures together and electrically connects the percutaneously connected device to the external electronics, and to repel in a second angular position to facilitate removal of the second connector structure from the first connector structure.« less
Access channels to the buried active site control substrate specificity in CYP1A P450 enzymes.
Urban, Philippe; Truan, Gilles; Pompon, Denis
2015-04-01
A cytochrome P450 active site is buried within the protein molecule and several channels connect the catalytic cavity to the protein surface. Their role in P450 catalysis is still matter of debate. The aim of this study was to understand the possible relations existing between channels and substrate specificity. Time course studies were carried out with a collection of polycyclic substrates of increasing sizes assayed with a library of wild-type and chimeric CYP1A enzymes. This resulted in a matrix of activities sufficiently large to allow statistical analysis. Multivariate statistical tools were used to decipher the correlation between observed activity shifts and sequence segment swaps. The global kinetic behavior of CYP1A enzymes toward polycyclic substrates is significantly different depending on the size of the substrate. Mutations which are close or lining the P450 channels significantly affect this discrimination, whereas mutations distant from the P450 channels do not. Size discrimination is taking place for polycyclic substrates at the entrance of the different P450 access channels. It is thus hypothesized that channels differentiate small from large substrates in CYP1A enzymes, implying that residues located at the surface of the protein may be implied in this differential recognition. Catalysis thus occurs after a two-step recognition process, one at the surface of the protein and the second within the catalytic cavity in enzymes with a buried active site. Copyright © 2014 Elsevier B.V. All rights reserved.
Cavity-based quantum networks with single atoms and optical photons
NASA Astrophysics Data System (ADS)
Reiserer, Andreas; Rempe, Gerhard
2015-10-01
Distributed quantum networks will allow users to perform tasks and to interact in ways which are not possible with present-day technology. Their implementation is a key challenge for quantum science and requires the development of stationary quantum nodes that can send and receive as well as store and process quantum information locally. The nodes are connected by quantum channels for flying information carriers, i.e., photons. These channels serve both to directly exchange quantum information between nodes and to distribute entanglement over the whole network. In order to scale such networks to many particles and long distances, an efficient interface between the nodes and the channels is required. This article describes the cavity-based approach to this goal, with an emphasis on experimental systems in which single atoms are trapped in and coupled to optical resonators. Besides being conceptually appealing, this approach is promising for quantum networks on larger scales, as it gives access to long qubit coherence times and high light-matter coupling efficiencies. Thus, it allows one to generate entangled photons on the push of a button, to reversibly map the quantum state of a photon onto an atom, to transfer and teleport quantum states between remote atoms, to entangle distant atoms, to detect optical photons nondestructively, to perform entangling quantum gates between an atom and one or several photons, and even provides a route toward efficient heralded quantum memories for future repeaters. The presented general protocols and the identification of key parameters are applicable to other experimental systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doria, Alberto; Gitti, Myriam; Brighenti, Fabrizio
2012-07-01
We present a study of the cavity system in the galaxy cluster RBS 797 based on Chandra and Very Large Array (VLA) data. RBS 797 (z = 0.35) is one of the most distant galaxy clusters in which two pronounced X-ray cavities have been discovered. The Chandra data confirm the presence of a cool core and indicate a higher metallicity along the cavity directions. This is likely due to the active galactic nucleus outburst, which lifts cool metal-rich gas from the center along the cavities, as seen in other systems. We find indications that the cavities are hotter than themore » surrounding gas. Moreover, the new Chandra images show bright rims contrasting with the deep, X-ray deficient cavities. The likely cause is that the expanding 1.4 GHz radio lobes have displaced the gas, compressing it into a shell that appears as bright cool arms. Finally, we show that the large-scale radio emission detected with our VLA observations may be classified as a radio mini-halo, powered by the cooling flow, as it nicely follows the trend P{sub radio} versus P{sub CF} predicted by the reacceleration model.« less
Foreign Body in the Oral Cavity Mimicking a Benign Connective Tissue Tumor
Ram, Saravanan; Sedghizadeh, Parish P.
2013-01-01
Foreign bodies may be embedded in the oral cavity either by traumatic injury or iatrogenically. The commonly encountered iatrogenic foreign bodies are restorative materials like amalgam, obturation materials, broken instruments, needles, and impression materials. This paper describes an asymptomatic presentation of a foreign body in the oral mucosa which clinically appeared like a benign connective tissue tumor. PMID:23634307
Foreign body in the oral cavity mimicking a benign connective tissue tumor.
Puliyel, Divya; Balouch, Amir; Ram, Saravanan; Sedghizadeh, Parish P
2013-01-01
Foreign bodies may be embedded in the oral cavity either by traumatic injury or iatrogenically. The commonly encountered iatrogenic foreign bodies are restorative materials like amalgam, obturation materials, broken instruments, needles, and impression materials. This paper describes an asymptomatic presentation of a foreign body in the oral mucosa which clinically appeared like a benign connective tissue tumor.
James T. Anderson; Karen A. Riesz
2013-01-01
Wildlife habitats connected with forested islands and their back channels (areas where commercial traffic is prohibited) on the Ohio River are valuable to diverse species. However, quantitative data on the importance of these areas to cavity-nesting birds are lacking. We compared cavity-nesting bird use and habitat between back and navigational channel sides of islands...
Phonon Routing in Integrated Optomechanical Cavity-waveguide Systems
2015-08-20
optomechanical crystal cavities connected by a dispersion-engineered phonon waveguide. Pulsed and continuous- wave measurements are first used to char- acterize...device layer of a silicon-on-insulator wafer (see App. A), and consists of several parts: an op- tomechanical cavity with co- localized optical and acous... localized cavity mode and the nearly- resonant phonon waveguide modes. The optical coupling waveg- uide is fabricated in the near-field of the nanobeam
Buttram, M.T.; Ginn, J.W.
1988-06-21
A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.
Lian, B; Cui, C L; Zhou, L; Song, X; Zhang, X S; Wu, D; Si, L; Chi, Z H; Sheng, X N; Mao, L L; Wang, X; Tang, B X; Yan, X Q; Kong, Y; Dai, J; Li, S M; Bai, X; Zheng, N; Balch, C M; Guo, J
2017-04-01
We examined whether mucosal melanomas are different in their clinical course and patterns of metastases when arising from different anatomic sites. Our hypothesis was that metastatic behavior would differ from primary mucosal melanomas at different anatomical sites. Clinical and pathological data from 706 patients were compared for their stage distribution, patterns of metastases, CKIT/BRAF mutation status, and overall survival for different anatomical sites. The anatomic sites of the primary mucosal melanomas were from the lower GI tract (26.5%), nasal cavity and paranasal sinuses (23%), gynecological sites (22.5%), oral cavity (15%), urological sites (5%), upper GI tract (5%), and other sites (3.0%). At initial diagnosis, 14.5% were stage I disease, 41% Stage II, 21.5% Stage III, and 23.0% stage IV. Predominant metastatic sites were regional lymph nodes (21.5%), lung (21%), liver (18.5%), and distant nodes (9%). Oral cavity mucosal melanoma had a higher incidence of regional nodal metastases (31.7% versus 19.8%, P = 0.009), and a higher incidence of lung metastases (32.5% versus 18.5%, P = 0.007) compared to other primary mucosal melanomas. There was a 10% incidence of CKIT mutation and 12% BRAF mutation. Mucosal melanomas from nasal pharyngeal and oral, gastrointestinal, gynecological, and urological had a similar survival with a 1-year survival rate (88%, 83%, 86%), 2-year survival rate (66%, 57%, 61%), 5-year survival rate (27%, 16%, 20%), respectively. The largest sample size allows, for the first time, a comparison of primary melanoma stage and patterns of metastases across anatomical sites. With few exceptions, the presenting stages, incidence of nodal and distant metastases, the site of predilection of distant metastases, or overall survival were similar despite different primary anatomic sites. These findings suggest that clinical trials involving mucosal melanomas and the administration of systemic therapy can be applied equally to mucosal melanomas regardless of their primary anatomic site. © The Author 2016. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kjems, Julie; Gothelf, Anita B.; Håkansson, Katrin
Purpose: The delineation of elective clinical target volumes in head and neck cancer (HNC) is important; however, the extent of lymph node levels necessary to include is debated. A comprehensive analysis of recurrence patterns in a large cohort of patients with HNC was performed, with an emphasis on recurrence in the retropharyngeal region and level IB. Methods and Materials: From 2005 to 2012, 942 patients with oropharyngeal, hypopharyngeal, laryngeal or oral cavity carcinomas were curatively treated with primary radiation therapy. The median follow-up period was 34 months, and 77% of the patients underwent intensity modulated radiation therapy. The retropharyngeal region wasmore » only routinely included in cases of involvement of the posterior pharynx wall and level IB only in cases of involvement of the oral cavity. In patients with regional recurrence, the anatomic site of the recurrence was assessed from the surgical descriptions or computed tomography scans and compared with the original radiation treatment plan (available from 2007 onward). The p16 status was available for 282 oropharynx carcinoma cases, with 65% p16-positive. Results: Of the 942 patients, 376 (40%) developed recurrences: 228 (24.2%) local, 123 (13.1%) regional, and 109 (11.6%) distant. In 700 patients with available treatment plans, retropharyngeal and level IB recurrence was observed in 2 and 7 patients, respectively. Eight patients (1.1%) had recurrence in a lymph node level not included in their primary treatment plan. For oropharynx carcinoma, the locoregional control rate (90% vs 70%) but not distant control rate (92% vs 87%), was significantly better in the p16-positive than in the p16-negative patients. Although fewer recurrences developed in the p16-positive group, patients with recurrence of p16-positive tumors were more likely to develop recurrence in distant sites. Conclusions: Retropharyngeal or level IB recurrence after primary HNC radiation therapy is rare. Thus, inclusion of these regions in the elective treatment volumes should be limited to patients with involvement of the posterior pharyngeal wall or oral cavity.« less
Long-term effects of musical training and functional plasticity in salience system.
Luo, Cheng; Tu, Shipeng; Peng, Yueheng; Gao, Shan; Li, Jianfu; Dong, Li; Li, Gujing; Lai, Yongxiu; Li, Hong; Yao, Dezhong
2014-01-01
Musicians undergoing long-term musical training show improved emotional and cognitive function, which suggests the presence of neuroplasticity. The structural and functional impacts of the human brain have been observed in musicians. In this study, we used data-driven functional connectivity analysis to map local and distant functional connectivity in resting-state functional magnetic resonance imaging data from 28 professional musicians and 28 nonmusicians. Compared with nonmusicians, musicians exhibited significantly greater local functional connectivity density in 10 regions, including the bilateral dorsal anterior cingulate cortex, anterior insula, and anterior temporoparietal junction. A distant functional connectivity analysis demonstrated that most of these regions were included in salience system, which is associated with high-level cognitive control and fundamental attentional process. Additionally, musicians had significantly greater functional integration in this system, especially for connections to the left insula. Increased functional connectivity between the left insula and right temporoparietal junction may be a response to long-term musical training. Our findings indicate that the improvement of salience network is involved in musical training. The salience system may represent a new avenue for exploration regarding the underlying foundations of enhanced higher-level cognitive processes in musicians.
Incidence and sites of distant metastases from head and neck cancer.
Ferlito, A; Shaha, A R; Silver, C E; Rinaldo, A; Mondin, V
2001-01-01
The incidence of distant metastases in head and neck squamous cell carcinoma (SCC) is relatively small in comparison to other malignancies. Distant metastases adversely impact survival and may significantly affect treatment planning. The incidence of distant metastases is influenced by location of the primary tumor, initial T and N stage of the neoplasm, and the presence or absence of regional control above the clavicle. Patients with advanced nodal disease have a high incidence of distant metastases, particularly in the presence of jugular vein invasion or extensive soft tissue disease in the neck. Primary tumors of advanced T stages in the hypopharynx, oropharynx and oral cavity are associated with the highest incidence of distant metastases. Pulmonary metastases are the most frequent in SCC, accounting for 66% of distant metastases. It may be difficult to distinguish pulmonary metastasis from a new primary tumor, particularly if solitary. Other metastatic sites include bone (22%), liver (10%), skin, mediastinum and bone marrow. An important question remains as to how intensely pre- and postoperative screening for distant metastases should be performed. Preoperative chest X-ray is warranted in all cases. If the primary tumor and nodal status place the patient at high risk for pulmonary metastasis, then preoperative computed tomography scan of the chest should be done. Screening for distant metastases at other sites is usually not indicated in SCC of the upper aerodigestive tract. Postoperatively, annual X-rays of the chest are usually sufficient, but in high-risk situations a chest X-ray performed every 3-6 months may be beneficial. Certain histologic types of primary tumor have greater or lesser propensity to metastasize distantly, and have a different natural history. Adenoid cystic carcinoma metastasizes frequently, even in the absence of extensive local or regional disease. Basaloid squamous cell carcinoma and neuroendocrine carcinomas also metastasize widely. Extensive evaluation for distant metastases is justified for these tumors. Knowledge of the natural history of various neoplasms and the factors that contribute to distant metastases as well as good judgement are essential for cost-effective treatment planning and decision-making with regard to pre- and postoperative evaluation for distant metastases in cancer of the head and neck. Copyright 2001 S. Karger AG, Basel
NASA Astrophysics Data System (ADS)
Tamura, Shuhei; Ikeda, Kohei; Okamura, Kotaro; Yoshii, Kazumichi; Hong, Feng-Lei; Horikiri, Tomoyuki; Kosaka, Hideo
2018-06-01
Long-distance quantum communication requires entanglement between distant quantum memories. For this purpose, photon transmission is necessary to connect the distant memories. Here, for the first time, we develop a two-step frequency conversion process (from a visible wavelength to a telecommunication wavelength and back) involving the use of independent two-frequency conversion media where the target quantum memories are nitrogen-vacancy centers in diamonds (with an emission/absorption wavelength of 637.2 nm), and experimentally characterize the performance of this process acting on light from an attenuated CW laser. A total conversion efficiency of approximately 7% is achieved. The noise generated in the frequency conversion processes is measured, and the signal-to-noise ratio is estimated for a single photon signal emitted by a nitrogen-vacancy (NV) center. The developed frequency conversion system has future applications via transmission through a long optical fiber channel at a telecommunication wavelength for a quantum repeater network.
Pre-conceptual design of the Z-LLE accelerator.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stygar, William A.
We begin with a model of 20 LTD modules, connected in parallel. We assume each LTD module consists of 10 LTD cavities, connected in series. We assume each cavity includes 20 LTD bricks, in parallel. Each brick is assumed to have a 40-nF capacitance and a 160-nH inductance. We use for this calculation the RLC-circuit model of an LTD system that was developed by Mazarakis and colleagues.
Microscopic Investigation of Materials Limitations of Superconducting RF Cavities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anlage, Steven
2017-08-04
Our overall goal is to contribute to the understanding of defects that limit the high accelerating gradient performance of Nb SRF cavities. Our approach is to develop a microscopic connection between materials defects and SRF performance. We developed a near-field microwave microscope to establish this connection. The microscope is based on magnetic hard drive write heads, which are designed to create very strong rf magnetic fields in very small volumes on a surface.
Customizing vacuum fluctuations for enhanced entanglement creation
NASA Astrophysics Data System (ADS)
Wang, Jin
2018-07-01
This paper connects the creation of entanglement through cavity enhanced decay rate with practical design parameters such as cavity dimension and cavity mirror reflectivity. The clarification of specific physical parameters on cavity enhanced emission in relation to entanglement creation is discussed. It is found that entanglement increases as the size of the cavity decreases, or the reflectivity of the cavity mirrors increases. Additionally, the negative effect of individual qubit decoherence on the entanglement is discussed. These results can be used to design or choose a practical system for implementing entanglement between two qubits for quantum computation and information processing.
Linear induction accelerator and pulse forming networks therefor
Buttram, Malcolm T.; Ginn, Jerry W.
1989-01-01
A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities.
Gyrotron cavity resonator with an improved value of Q
Stone, David S.; Shively, James F.
1982-10-26
A gyrotron cavity resonator is connected smoothly and directly to an output waveguide with a very gradually tapered wall so that values of external Q lower than twice the diffraction limit are obtainable.
Hohimer, John P.; Craft, David C.
1994-01-01
Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction.
Flow through the nasal cavity of the spiny dogfish, Squalus acanthias
NASA Astrophysics Data System (ADS)
Timm-Davis, L. L.; Fish, F. E.
2015-12-01
The nasal cavity of spiny dogfish is a blind capsule with no internal connection to the oral cavity. Water is envisioned to flow through the cavity in a smooth, continuous flow pattern; however, this assumption is based on previous descriptions of the morphology of the olfactory cavity. No experimentation on the flow through the internal nasal cavity has been reported. Morphology of the head of the spiny dogfish ( Squalus acanthias) does not suggest a close external connection between the oral and nasal systems. However, dye visualization showed that there was flow through the nasal apparatus and from the excurrent nostril to the mouth when respiratory flows were simulated. The hydrodynamic flow through the nasal cavity was observed from flow tank experiments. The dorsum of the nasal cavity of shark heads from dead animals was exposed by dissection and a glass plate was glued over of the exposed cavity. When the head was placed in a flow, dye was observed to be drawn passively into the cavity showing a complex, three-dimensional hydrodynamic flow. Dye entered the incurrent nostril, flowed through the nasal lamellae, crossed over and under the nasal valve, and circulated around the nasal valve before exiting the excurrent nostril. When the nasal valve was removed, the dye became stagnant and back flowed out through the incurrent nostril. The single nasal valve has a hydrodynamic function that organizes a coherent flow of water through the cavity without disruption. The results suggest that the morphology of the nasal apparatus in concert with respiratory flow and ambient flows from active swimming can be used to draw water through the olfactory cavity of the shark.
Resonant-cavity antenna for plasma heating
Perkins, Jr., Francis W.; Chiu, Shiu-Chu; Parks, Paul; Rawls, John M.
1987-01-01
Disclosed is a resonant coil cavity wave launcher for energizing a plasma immersed in a magnetic field. Energization includes launching fast Alfven waves to excite ion cyclotron frequency resonances in the plasma. The cavity includes inductive and capacitive reactive members spaced no further than one-quarter wavelength from a first wall confinement chamber of the plasma. The cavity wave launcher is energized by connection to a waveguide or transmission line carrying forward power from a remote radio frequency energy source.
Aubert, J.H.; Chapman, R.N.; Kraynik, A.M.
1983-06-30
A helical screw viscometer for the measurement of the viscosity of Newtonian and non-Newtonian fluids comprising an elongated cylindrical container closed by end caps defining a circular cylindrical cavity within the container, a cylindrical rotor member having a helical screw or ribbon flight carried by the outer periphery thereof rotatably carried within the cavity whereby the fluid to be measured is confined in the cavity filling the space between the rotor and the container wall. The rotor member is supported by axle members journaled in the end caps, one axle extending through one end cap and connectable to a drive source. A pair of longitudinally spaced ports are provided through the wall of the container in communication with the cavity and a differential pressure meter is connected between the ports for measuring the pressure drop caused by the rotation of the helical screw rotor acting on the confined fluid for computing viscosity.
Cliques of Neurons Bound into Cavities Provide a Missing Link between Structure and Function.
Reimann, Michael W; Nolte, Max; Scolamiero, Martina; Turner, Katharine; Perin, Rodrigo; Chindemi, Giuseppe; Dłotko, Paweł; Levi, Ran; Hess, Kathryn; Markram, Henry
2017-01-01
The lack of a formal link between neural network structure and its emergent function has hampered our understanding of how the brain processes information. We have now come closer to describing such a link by taking the direction of synaptic transmission into account, constructing graphs of a network that reflect the direction of information flow, and analyzing these directed graphs using algebraic topology. Applying this approach to a local network of neurons in the neocortex revealed a remarkably intricate and previously unseen topology of synaptic connectivity. The synaptic network contains an abundance of cliques of neurons bound into cavities that guide the emergence of correlated activity. In response to stimuli, correlated activity binds synaptically connected neurons into functional cliques and cavities that evolve in a stereotypical sequence toward peak complexity. We propose that the brain processes stimuli by forming increasingly complex functional cliques and cavities.
Frontal lobe connectivity and cognitive impairment in pediatric frontal lobe epilepsy.
Braakman, Hilde M H; Vaessen, Maarten J; Jansen, Jacobus F A; Debeij-van Hall, Mariette H J A; de Louw, Anton; Hofman, Paul A M; Vles, Johan S H; Aldenkamp, Albert P; Backes, Walter H
2013-03-01
Cognitive impairment is frequent in children with frontal lobe epilepsy (FLE), but its etiology is unknown. With functional magnetic resonance imaging (fMRI), we have explored the relationship between brain activation, functional connectivity, and cognitive functioning in a cohort of pediatric patients with FLE and healthy controls. Thirty-two children aged 8-13 years with FLE of unknown cause and 41 healthy age-matched controls underwent neuropsychological assessment and structural and functional brain MRI. We investigated to which extent brain regions activated in response to a working memory task and assessed functional connectivity between distant brain regions. Data of patients were compared to controls, and patients were grouped as cognitively impaired or unimpaired. Children with FLE showed a global decrease in functional brain connectivity compared to healthy controls, whereas brain activation patterns in children with FLE remained relatively intact. Children with FLE complicated by cognitive impairment typically showed a decrease in frontal lobe connectivity. This decreased frontal lobe connectivity comprised both connections within the frontal lobe as well as connections from the frontal lobe to the parietal lobe, temporal lobe, cerebellum, and basal ganglia. Decreased functional frontal lobe connectivity is associated with cognitive impairment in pediatric FLE. The importance of impairment of functional integrity within the frontal lobe network, as well as its connections to distant areas, provides new insights in the etiology of the broad-range cognitive impairments in children with FLE. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.
AUTOMATIC FREQUENCY CONTROL SYSTEM
Hansen, C.F.; Salisbury, J.D.
1961-01-10
A control is described for automatically matching the frequency of a resonant cavity to that of a driving oscillator. The driving oscillator is disconnected from the cavity and a secondary oscillator is actuated in which the cavity is the frequency determining element. A low frequency is mixed with the output of the driving oscillator and the resultant lower and upper sidebands are separately derived. The frequencies of the sidebands are compared with the secondary oscillator frequency. deriving a servo control signal to adjust a tuning element in the cavity and matching the cavity frequency to that of the driving oscillator. The driving oscillator may then be connected to the cavity.
Koyama, Satoshi; Nakamura, Yosuke; Yokoyama, Yuko; Morisaki, Tsuyoshi; Fukuhara, Takahiro; Fujiwara, Kazunori; Kitano, Hiroya; Takeuchi, Hiromi
2017-10-01
Basaloid squamous cell carcinoma (BSCC) is a histologically distinctive variant of squamous cell carcinoma comprising basal cell carcinoma and squamous cell carcinoma. BSCC is aggressive and shows a poor prognosis because of frequent lymph node invasion and distant metastases. BSCC preferentially occurs in the cervix, thymus, and esophagus and is uncommonly found in the head and neck region. BSCC in the nasal cavity or paranasal sinus is particularly rare. Inverted papilloma is an uncommon, benign tumor with a propensity to be associated with malignancy; however, BSCC arising in an inverted papilloma has never been reported. Here we report a case of a 56-year-old woman with BSCC arising in an inverted papilloma in the nasal cavity. The woman was referred to our hospital for epistaxis, nasal congestion, and dysphagia. A tumor was observed to completely occupy the left nasal cavity. The biopsy specimen was histologically diagnosed as papilloma. Computed tomography demonstrated a tumor with heterogeneous contrast effect occupying the left nasal cavity; however, extra-nasal tract extension was not observed. We performed endoscopic excision of the tumor. Microscopic findings confirmed the diagnosis of BSCC arising from an inverted papilloma. No tumor recurrence has been observed for 13 months after surgery. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Campbell, Gene K.
1983-01-01
A pumping system is described for pumping fluids, such as water with entrained mud and small rocks, out of underground cavities such as drilled wells, which can effectively remove fluids down to a level very close to the bottom of the cavity and which can operate solely by compressed air pumped down through the cavity. The system utilizes a subassembly having a pair of parallel conduit sections (44, 46) adapted to be connected onto the bottom of a drill string utilized for drilling the cavity, the drill string also having a pair of coaxially extending conduits. The subassembly includes an upper portion which has means for connection onto the drill string and terminates the first conduit of the drill string in a plenum (55). A compressed air-driven pump (62) is suspended from the upper portion. The pump sucks fluids from the bottom of the cavity and discharges them into the second conduit. Compressed air pumped down through the first conduit (46) to the plenum powers the compressed air-driven pump and aerates the fluid in the second conduit to lift it to the earth's surface.
Patikoglou, Georgia A; Westblade, Lars F; Campbell, Elizabeth A; Lamour, Valérie; Lane, William J; Darst, Seth A
2007-09-21
The Escherichia coli Rsd protein binds tightly and specifically to the RNA polymerase (RNAP) sigma(70) factor. Rsd plays a role in alternative sigma factor-dependent transcription by biasing the competition between sigma(70) and alternative sigma factors for the available core RNAP. Here, we determined the 2.6 A-resolution X-ray crystal structure of Rsd bound to sigma(70) domain 4 (sigma(70)(4)), the primary determinant for Rsd binding within sigma(70). The structure reveals that Rsd binding interferes with the two primary functions of sigma(70)(4), core RNAP binding and promoter -35 element binding. Interestingly, the most highly conserved Rsd residues form a network of interactions through the middle of the Rsd structure that connect the sigma(70)(4)-binding surface with three cavities exposed on distant surfaces of Rsd, suggesting functional coupling between sigma(70)(4) binding and other binding surfaces of Rsd, either for other proteins or for as yet unknown small molecule effectors. These results provide a structural basis for understanding the role of Rsd, as well as its ortholog, AlgQ, a positive regulator of Pseudomonas aeruginosa virulence, in transcription regulation.
Crystal structure of the Escherichia coli regulator of σ70, Rsd, in complex with σ70 domain 4
Patikoglou, Georgia A.; Westblade, Lars F.; Campbell, Elizabeth A.; Lamour, Valérie; Lane, William J.; Darst, Seth A.
2007-01-01
Summary The Escherichia coli Rsd protein binds tightly and specifically to the RNA polymerase (RNAP) σ70 factor. Rsd plays a role in alternative σ factor-dependent transcription by biasing the competition between σ70 and alternative σ factors for the available core RNAP. Here, we determined the 2.6 Å-resolution X-ray crystal structure of Rsd bound to σ70 domain 4 (σ704), the primary determinant for Rsd binding within σ70. The structure reveals that Rsd binding interferes with the two primary functions of σ704, core RNAP binding and promoter –35 element binding. Interestingly, the most highly conserved Rsd residues form a network of interactions through the middle of the Rsd structure that connect the σ704-binding surface with three cavities exposed on distant surfaces of Rsd, suggesting functional coupling between σ704 binding and other binding surfaces of Rsd, either for other proteins or for as yet unknown small molecule effectors. These results provide a structural basis for understanding the role of Rsd, as well as its ortholog, AlgQ, a positive regulator of Pseudomonas aeruginosa virulence, in transcription regulation. PMID:17681541
DOE Office of Scientific and Technical Information (OSTI.GOV)
Patikoglou,G.; Westblade, L.; Campbell, E.
The Escherichia coli Rsd protein binds tightly and specifically to the RNA polymerase (RNAP) {sigma}{sup 70} factor. Rsd plays a role in alternative {sigma} factor-dependent transcription by biasing the competition between {sigma}{sup 70} and alternative {sigma} factors for the available core RNAP. Here, we determined the 2.6 {angstrom}-resolution X-ray crystal structure of Rsd bound to {sigma}{sup 70} domain 4 ({sigma}{sup 70}{sub 4}), the primary determinant for Rsd binding within {sigma}{sup 70}. The structure reveals that Rsd binding interferes with the two primary functions of {sigma}{sup 70}{sub 4}, core RNAP binding and promoter -35 element binding. Interestingly, the most highly conservedmore » Rsd residues form a network of interactions through the middle of the Rsd structure that connect the {sigma}{sup 70}{sub 4}-binding surface with three cavities exposed on distant surfaces of Rsd, suggesting functional coupling between {sigma}{sup 70}{sub 4} binding and other binding surfaces of Rsd, either for other proteins or for as yet unknown small molecule effectors. These results provide a structural basis for understanding the role of Rsd, as well as its ortholog, AlgQ, a positive regulator of Pseudomonas aeruginosa virulence, in transcription regulation.« less
Hohimer, J.P.; Craft, D.C.
1994-09-20
Unidirectional ring lasers formed by integrating nonreciprocal optical elements into the resonant ring cavity is disclosed. These optical elements either attenuate light traveling in a nonpreferred direction or amplify light traveling in a preferred direction. In one preferred embodiment the resonant cavity takes the form of a circle with an S-shaped crossover waveguide connected to two points on the interior of the cavity such that light traveling in a nonpreferred direction is diverted from the cavity into the crossover waveguide and reinjected out of the other end of the crossover waveguide into the cavity as light traveling in the preferred direction. 21 figs.
NASA NASA CONNECT: Special World Space Congress. [Videotape].
ERIC Educational Resources Information Center
National Aeronautics and Space Administration, Hampton, VA. Langley Research Center.
NASA CONNECT is an annual series of free integrated mathematics, science, and technology instructional distance learning programs for students in grades 5-8. This video presents the World Space Congress 2002, the meeting of the decade for space professionals. Topics discussed range from the discovery of distant planets to medical advancements,…
Geometric controls of the flexural gravity waves on the Ross Ice Shelf
NASA Astrophysics Data System (ADS)
Sergienko, O. V.
2017-12-01
Long-period ocean waves, formed locally or at distant sources, can reach sub-ice-shelf cavities and excite coupled motion in the cavity and the ice shelf - flexural gravity waves. Three-dimensional numerical simulations of the flexural gravity waves on the Ross Ice Shelf show that propagation of these waves is strongly controlled by the geometry of the system - the cavity shape, its water-column thickness and the ice-shelf thickness. The results of numerical simulations demonstrate that propagation of the waves is spatially organized in beams, whose orientation is determined by the direction of the of the open ocean waves incident on the ice-shelf front. As a result, depending on the beams orientation, parts of the Ross Ice Shelf experience significantly larger flexural stresses compared to other parts where the flexural gravity beams do not propagate. Very long-period waves can propagate farther away from the ice-shelf front exciting flexural stresses in the vicinity of the grounding line.
Oral Bacterial and Fungal Microbiome Impacts Colorectal Carcinogenesis.
Klimesova, Klara; Jiraskova Zakostelska, Zuzana; Tlaskalova-Hogenova, Helena
2018-01-01
Host's physiology is significantly influenced by microbiota colonizing the epithelial surfaces. Complex microbial communities contribute to proper mucosal barrier function, immune response, and prevention of pathogen invasion and have many other crucial functions. The oral cavity and large intestine are distant parts of the digestive tract, both heavily colonized by commensal microbiota. Nevertheless, they feature different proportions of major bacterial and fungal phyla, mostly due to distinct epithelial layers organization and different oxygen levels. A few obligate anaerobic strains inhabiting the oral cavity are involved in the pathogenesis of oral diseases. Interestingly, these microbiota components are also enriched in gut inflammatory and tumor tissue. An altered microbiota composition - dysbiosis - and formation of polymicrobial biofilms seem to play important roles in the development of oral diseases and colorectal cancer. In this review, we describe the differences in composition of commensal microbiota in the oral cavity and large intestine and the mechanisms by which microbiota affect the inflammatory and carcinogenic response of the host.
Doré, M; Martin, S; Delpon, G; Clément, K; Campion, L; Thillays, F
2017-02-01
To evaluate local control and adverse effects after postoperative hypofractionated stereotactic radiosurgery in patients with brain metastasis. We reviewed patients who had hypofractionated stereotactic radiosurgery (7.7Gy×3 prescribed to the 70% isodose line, with 2mm planning target volume margin) following resection from March 2008 to January 2014. The primary endpoint was local failure defined as recurrence within the surgical cavity. Secondary endpoints were distant failure rates and the occurrence of radionecrosis. Out of 95 patients, 39.2% had metastatic lesions from a non-small cell lung cancer primary tumour. The median Graded Prognostic Assessment score was 3 (48% of patients). One-year local control rates were 84%. Factors associated with improved local control were no cavity enhancement on pre-radiation MRI (P<0.00001), planning target volume less than 12cm 3 (P=0.005), Graded Prognostic Assessment score 2 or above (P=0.009). One-year distant cerebral control rates were 56%. Thirty-three percent of patients received whole brain radiation therapy. Histologically proven radionecrosis of brain tissue occurred in 7.2% of cases. The size of the preoperative lesion and the volume of healthy brain tissue receiving 21Gy (V 21 ) were both predictive of the incidence of radionecrosis (P=0.010 and 0.036, respectively). Adjuvant hypofractionated stereotactic radiosurgery to the postoperative cavity in patients with brain metastases results in excellent local control in selected patients, helps delay the use of whole brain radiation, and is associated with a relatively low risk of radionecrosis. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.
ISM abundances and history: a 3D, solar neighborhood view
NASA Astrophysics Data System (ADS)
Lallement, R.; Vergely, J.-L.; Puspitarini, L.
For observational reasons, the solar neighborhood is particularly suitable for the study of the multi-phase interstellar (IS) medium and the search for traces of its temporal evolution. On the other hand, by a number of aspects it seems to be a peculiar region. We use recent 3D maps of the IS dust based on color excess data as well as former maps of the gas to illustrate how such maps can be used to shed additional light on the specificity of the local medium, its history and abundance pattern. 3D maps reveal a gigantic cavity located in the third quadrant and connected to the Local Bubble, the latter itself running into an elongated cavity toward l≃ 70°. Most nearby cloud complexes of the so-called Gould belt but also more distant clouds seem to border a large fraction of this entire structure. The IS medium with the large cavity appears ionized and dust-poor, as deduced from ionized calcium and neutral sodium to dust ratios. The geometry favors the proposed scenario of Gould belt-Local Arm formation through the braking of a supercloud by interaction with a spiral density wave \\citep{olano01}. The highly variable D/H ratio in the nearby IS gas may also be spatially related to the global structure. We speculate about potential consequences of the supercloud encounter and dust-gas decoupling during its braking, in particular the formation of strong inhomogeneities in both the dust to gas abundance ratio and the dust characteristics: (i) during the ≃ 500 Myrs prior to the collision, dust within the supercloud may have been gradually, strongly enriched in D due to an absence of strong stellar formation and preferential adsorption of D \\citep{jura82,draine03} ; (ii) during its interaction with the Plane and the braking dust-rich and dust-poor regions may have formed due to differential gas drag, the dust being more concentrated in the dense areas; strong radiation pressure from OB associations at the boundary of the left-behind giant cavity may have also helped in emptying the cavity from its dust at the profit of the central parts of the supercloud ; (iii) present D/H variations could be due to the combination of those dust inhomogeneities and posterior, localized deuterium release by grains in recent star forming regions. In this case, the true local D/H ratio has an intermediate value within the observed range.
Video-mediated communication to support distant family connectedness.
Furukawa, Ryoko; Driessnack, Martha
2013-02-01
It can be difficult to maintain family connections with geographically distant members. However, advances in computer-human interaction (CHI) systems, including video-mediated communication (VMC) are emerging. While VMC does not completely substitute for physical face-to-face communication, it appears to provide a sense of virtual copresence through the addition of visual and contextual cues to verbal communication between family members. The purpose of this study was to explore current patterns of VMC use, experiences, and family functioning among self-identified VMC users separated geographically from their families. A total of 341 participants (ages 18 to above 70) completed an online survey and Family APGAR. Ninty-six percent of the participants reported that VMC was the most common communication method used and 60% used VMC at least once/week. The most common reason cited for using VMC over other methods of communication was the addition of visual cues. A significant difference between the Family APGAR scores and the number of positive comments about VMC experience was also found. This exploratory study provides insight into the acceptance of VMC and its usefulness in maintaining connections with distant family members.
Circuit QED with qutrits: Coupling three or more atoms via virtual-photon exchange
NASA Astrophysics Data System (ADS)
Zhao, Peng; Tan, Xinsheng; Yu, Haifeng; Zhu, Shi-Liang; Yu, Yang
2017-10-01
We present a model to describe a generic circuit QED system which consists of multiple artificial three-level atoms, namely, qutrits, strongly coupled to a cavity mode. When the state transition of the atoms disobeys the selection rules the process that does not conserve the number of excitations can happen determinatively. Therefore, we can realize coherent exchange interaction among three or more atoms mediated by the exchange of virtual photons. In addition, we generalize the one-cavity-mode mediated interactions to the multicavity situation, providing a method to entangle atoms located in different cavities. Using experimentally feasible parameters, we investigate the dynamics of the model including three cyclic-transition three-level atoms, for which the two lowest energy levels can be treated as qubits. Hence, we have found that two qubits can jointly exchange excitation with one qubit in a coherent and reversible way. In the whole process, the population in the third level of atoms is negligible and the cavity photon number is far smaller than 1. Our model provides a feasible scheme to couple multiple distant atoms together, which may find applications in quantum information processing.
Acoustoelasticity. [sound-structure interaction
NASA Technical Reports Server (NTRS)
Dowell, E. H.
1977-01-01
Sound or pressure variations inside bounded enclosures are investigated. Mathematical models are given for determining: (1) the interaction between the sound pressure field and the flexible wall of a Helmholtz resonator; (2) coupled fluid-structural motion of an acoustic cavity with a flexible and/or absorbing wall; (3) acoustic natural modes in multiple connected cavities; and (4) the forced response of a cavity with a flexible and/or absorbing wall. Numerical results are discussed.
1991-05-01
Knox, 1974). Studies have demonstrated the presence of streptococci and lactobacilli throughout the oral cavity , as well as in developing dental... oral cavity , it is apparent that these compounds have the potential to play a role in the initiation and progression of inflammatory oral disease...junctional epithelium and into the gingival sulcus and oral cavity . The perivascular connective tissue matrix becomes altered most likely by
NASA Technical Reports Server (NTRS)
Athavale, M. M.; Przekwas, A. J.; Hendricks, R. C.; Steinetz, B. M.
1995-01-01
A numerical analysis methodology and solutions of the interaction between the power stream and multiply-connected multi-cavity sealed secondary flow fields are presented. Flow solutions for a multi-cavity experimental rig were computed and compared with experimental data of Daniels and Johnson. The flow solutions illustrate the complex coupling between the main-path and the cavity flows as well as outline the flow thread that exists throughout the subplatform multiple cavities and seals. The analysis also shows that the de-coupled solutions on single cavities is inadequate. The present results show trends similar to the T-700 engine data that suggests the changes in the CDP seal altered the flow fields throughout the engine and affected the engine performance.
Quantized mode of a leaky cavity
NASA Astrophysics Data System (ADS)
Dutra, S. M.; Nienhuis, G.
2000-12-01
We use Thomson's classical concept of mode of a leaky cavity to develop a quantum theory of cavity damping. This theory generalizes the conventional system-reservoir theory of high-Q cavity damping to arbitrary Q. The small system now consists of damped oscillators corresponding to the natural modes of the leaky cavity rather than undamped oscillators associated with the normal modes of a fictitious perfect cavity. The formalism unifies semiclassical Fox-Li modes and the normal modes traditionally used for quantization. It also lays the foundations for a full quantum description of excess noise. The connection with Siegman's semiclassical work is straightforward. In a wider context, this theory constitutes a radical departure from present models of dissipation in quantum mechanics: unlike conventional models, system and reservoir operators no longer commute with each other. This noncommutability is an unavoidable consequence of having to use natural cavity modes rather than normal modes of a fictitious perfect cavity.
Prominence Mass Supply and the Cavity
NASA Technical Reports Server (NTRS)
Schmit, Donald J.; Gibson, S.; Luna, M.; Karpen, J.; Innes, D.
2013-01-01
A prevalent but untested paradigm is often used to describe the prominence-cavity system; the cavity is under-dense because it it evacuated by supplying mass to the condensed prominence. The thermal non-equilibrium (TNE) model of prominence formation offers a theoretical framework to predict the thermodynamic evolutin of the prominence and the surrounding corona. We examine the evidence for a prominence-cavity connection by comparing the TNE model and diagnostics of dynamic extreme ultraviolet (EUV) emission surrounding the prominence, specifically prominence horns. Horns are correlated extensions of prminence plasma and coronal plasma which appear to connect the prominence and cavity. The TNE model predicts that large-scale brightenings will occur in the Solar Dynamics Observatory Atmospheric Imaging Assembly 171 A badpass near he prominence that are associated with the cooling phase of condensation formation. In our simulations, variations in the magnitude of footpoint heating lead to variations in the duration, spatial scale, and temporal offset between emission enhancements in the other EUV bandpasses. While these predictions match well a subset of the horn observations, the range of variations in the observed structures is not captured by the model. We discuss the implications of one-dimensional loop simulations for the three-dimensional time-averaged equilibrium in the prominence and the cavity. Evidence suggests that horns are likely caused by condensing prominence plasma, but the larger question of whether this process produces a density-depleted cavity requires a more tightly constrained model of heating and better knowledge of the associated magnetic structure.
Schaefer, Christopher E.; Beer, Robert C.; McCall, Mark D.
2000-01-01
A high power connection system adapted for automotive environments which provides environmental and EMI shielding includes a female connector, a male connector, and a panel mount. The female connector includes a female connector base and a snap fitted female connector cover. The male connector includes a male connector base and a snap fitted male connector cover. The female connector base has at least one female power terminal cavity for seatably receiving a respective female power terminal. The male connector base has at least one male power terminal cavity for seatably receiving a respective male power terminal. The female connector is covered by a cover seal and a conductive shroud. A pair of lock arms protrude outward from the front end of the male connector base, pass through the panel mount and interface with a lever of a lever rotatably connected to the shroud to thereby mechanically assist mating of the male and female connectors. Safety terminals in the male and female connectors provide a last-to-connect-first-to-break connection with an HVIL circuit.
Integration of photoactive and electroactive components with vertical cavity surface emitting lasers
Bryan, R.P.; Esherick, P.; Jewell, J.L.; Lear, K.L.; Olbright, G.R.
1997-04-29
A monolithically integrated optoelectronic device is provided which integrates a vertical cavity surface emitting laser and either a photosensitive or an electrosensitive device either as input or output to the vertical cavity surface emitting laser either in parallel or series connection. Both vertical and side-by-side arrangements are disclosed, and optical and electronic feedback means are provided. Arrays of these devices can be configured to enable optical computing and neural network applications. 9 figs.
Integration of photoactive and electroactive components with vertical cavity surface emitting lasers
Bryan, Robert P.; Esherick, Peter; Jewell, Jack L.; Lear, Kevin L.; Olbright, Gregory R.
1997-01-01
A monolithically integrated optoelectronic device is provided which integrates a vertical cavity surface emitting laser and either a photosensitive or an electrosensitive device either as input or output to the vertical cavity surface emitting laser either in parallel or series connection. Both vertical and side-by-side arrangements are disclosed, and optical and electronic feedback means are provided. Arrays of these devices can be configured to enable optical computing and neural network applications.
Casting Apparatus Including A Gas Driven Molten Metal Injector And Method
Trudel, David R.; Meyer, Thomas N.; Kinosz, Michael J.; Arnaud, Guy; Bigler, Nicolas
2003-06-17
The filtering molten metal injector system includes a holder furnace, a casting mold supported above the holder furnace, and at least one molten metal injector supported from a bottom side of the casting mold. The holder furnace contains a supply of molten metal. The mold defines a mold cavity for receiving the molten metal from the holder furnace. The molten metal injector projects into the holder furnace. The molten metal injector includes a cylinder defining a piston cavity housing a reciprocating piston for pumping the molten metal upward from the holder furnace to the mold cavity. The cylinder and piston are at least partially submerged in the molten metal when the holder furnace contains the molten metal. The cylinder or the piston includes a molten metal intake for receiving the molten metal into the piston cavity when the holder furnace contains molten metal. A conduit connects the piston cavity to the mold cavity. A molten metal filter is located in the conduit for filtering the molten metal passing through the conduit during the reciprocating movement of the piston. The molten metal intake may be a valve connected to the cylinder, a gap formed between the piston and an open end of the cylinder, an aperture defined in the sidewall of the cylinder, or a ball check valve incorporated into the piston. A second molten metal filter preferably covers the molten metal intake to the injector.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prabhu, Roshan; Shu, Hui-Kuo; Winship Cancer Institute, Emory University, Atlanta, GA
2012-05-01
Purpose: To describe the use of radiosurgery (RS) alone to the resection cavity after resection of brain metastases as an alternative to adjuvant whole-brain radiotherapy (WBRT). Methods and Materials: Sixty-two patients with 64 cavities were treated with linear accelerator-based RS alone to the resection cavity after surgical removal of brain metastases between March 2007 and August 2010. Fifty-two patients (81%) had a gross total resection. Median cavity volume was 8.5 cm{sup 3}. Forty-four patients (71%) had a single metastasis. Median marginal and maximum doses were 18 Gy and 20.4 Gy, respectively. Sixty-one cavities (95%) had gross tumor volume to planningmore » target volume expansion of {>=}1 mm. Results: Six-month and 1-year actuarial local recurrence rates were 14% and 22%, respectively, with a median follow-up period of 9.7 months. Six-month and 1-year actuarial distant brain recurrence, total intracranial recurrence, and freedom from WBRT rates were 31% and 51%, 41% and 63%, and 91% and 74%, respectively. The symptomatic cavity radiation necrosis rate was 8%, with 2 patients (3%) undergoing surgery. Of the 11 local failures, 8 were in-field, 1 was marginal, and 2 were both (defined as in-field if {>=}90% of recurrence within the prescription isodose and marginal if {>=}90% outside of the prescription isodose). Conclusions: The high rate of in-field cavity failure suggests that geographic misses with highly conformal RS are not a major contributor to local recurrence. The current dosing regimen derived from Radiation Therapy Oncology Group protocol 90-05 should be optimized in this patient population before any direct comparison with WBRT.« less
Climatic similarity and biological exchange in the worldwide airline transportation network
Tatem, Andrew J; Hay, Simon I
2007-01-01
Recent increases in the rates of biological invasion and spread of infectious diseases have been linked to the continued expansion of the worldwide airline transportation network (WAN). Here, the global structure of the WAN is analysed in terms of climatic similarity to illuminate the risk of deliberate or accidental movements of climatically sensitive organisms around the world. From over 44 000 flight routes, we show, for each month of an average year, (i) those scheduled routes that link the most spatially distant but climatically similar airports, (ii) the climatically best-connected airports, and (iii) clusters of airports with similar climatic features. The way in which traffic volumes alter these findings is also examined. Climatic similarity across the WAN is skewed (most geographically close airports are climatically similar) but heavy-tailed (there are considerable numbers of geographically distant but climatically similar airports), with climate similarity highest in the June–August period, matching the annual peak in air traffic. Climatically matched, geographically distant airports form subnetworks within the WAN that change throughout the year. Further, the incorporation of passenger and freight traffic data highlight at greater risk of invasion those airports that are climatically well connected by numerous high capacity routes. PMID:17426013
Turbo-alternator-compressor design for supercritical high density working fluids
Wright, Steven A.; Fuller, Robert L.
2013-03-19
Techniques for generating power are provided. Such techniques involve a thermodynamic system including a housing, a turbine positioned in a turbine cavity of the housing, a compressor positioned in a compressor cavity of the housing, and an alternator positioned in a rotor cavity between the turbine and compressor cavities. The compressor has a high-pressure face facing an inlet of the compressor cavity and a low-pressure face on an opposite side thereof. The alternator has a rotor shaft operatively connected to the turbine and compressor, and is supported in the housing by bearings. Ridges extending from the low-pressure face of the compressor may be provided for balancing thrust across the compressor. Seals may be positioned about the alternator for selectively leaking fluid into the rotor cavity to reduce the temperature therein.
Baker, W.R.
1958-05-01
A protective system for high-energy resonant cavities is described. It is particularly directed to the discharging of resonant cavities for preventing energy back flow through associated equipment as a result of faults. The invention in general provides means defining a spark gap communicating with the interior of a cavity or waveguide adapted for high-power energization or an evacuated chamber containing an electrode having a large power differential from the wall or other electrode. A control or trigger circuit is connected between a power supply energizing the cavity and the spark gap whereby reverse current flow in the power supply circuit instantaneously triggers the spark gap to initiate discharge within the cavity, whereupon cavity energy discharges across the gap, or with an electrode present the electrode discharges to one of the spark gap elements.
He, You; Chen, Xiao-Yong; Xiao, Ti-Qao; Yang, Jun-Xing
2013-10-01
Sinocyclocheilus is a cave-dwelling cyprinid genus endemic to southwest China. Several species possess a conspicuous horn on their head, which has been suggested as a constructive troglomorphic trait but lacks substantial evidence. We used non-invasive, high spatial resolution synchrotron X-ray microtomography to investigate the three-dimensional (3D) morphology of the horn of Sinocyclocheilus hyalinus, one of eight such troglobiotic species. 3D renderings demonstrated the osteological components, which were comprised of a rear wall comprised of the supraoccipital bone, a remaining frontal wall with numerous fenestrae, and the bottom continuous with the parietal and epiotic. A horn cavity occurred within the horn. The fenestrae in the frontal wall were continuous in the horn cavity and showed elaborate channeling, and were, connected to the cranial cavity by soft tissue. We tentatively called this configuration the "otocornual connection" due to its anatomic and putative functional similarity to the otolateralic connection in clupeids and loricariids, which provide an indirect pathway to enhance perception of underwater sound signals. This study provides a functional morphology context for further histological and physiological investigations of such horn structures in Sinocyclocheilus cavefish, and we suggest that the horn might enhance acoustic perception to compensate for visual loss in subterranean life, which warrants future physiological examination as lab-reared S. hyalinus become available. Sinocyclocheilus is a cave-dwelling cyprinid genus endemic to southwest China. Several species possess a conspicuous horn on their head, which has been suggested as a constructive troglomorphic trait but lacks substantial evidence. We used non-invasive, high spatial resolution synchrotron X-ray microtomography to investigate the three-dimensional (3D) morphology of the horn of Sinocyclocheilus hyalinus , one of eight such troglobiotic species. 3D renderings demonstrated the osteological components, which were comprised of a rear wall comprised of the supraoccipital bone, a remaining frontal wall with numerous fenestrae, and the bottom continuous with the parietal and epiotic. A horn cavity occurred within the horn. The fenestrae in the frontal wall were continuous in the horn cavity and showed elaborate channeling, and were, connected to the cranial cavity by soft tissue. We tentatively called this configuration the "otocornual connection" due to its anatomic and putative functional similarity to the otolateralic connection in clupeids and loricariids, which provide an indirect pathway to enhance perception of underwater sound signals. This study provides a functional morphology context for further histological and physiological investigations of such horn structures in Sinocyclocheilus cavefish, and we suggest that the horn might enhance acoustic perception to compensate for visual loss in subterranean life, which warrants future physiological examination as lab-reared S. hyalinus become available.
NASA Astrophysics Data System (ADS)
Shi, Deyong; Song, Wenyan; Wang, Yuhang; Wang, Yanhua
2017-08-01
In this work, the effects of cavity flameholder configurations on flameholding and performances of kerosene fueled scramjet combustor were studied experimentally and numerically. For experiments, a directly connected ground facility was used and clean high enthalpy air, with a total temperature of 800 K and a total pressure of 800 Kpa, was provided by an electricity resistance heater. To investigate the effects of cavity configurations on flameholding capacity and reacting-flow characteristics, three different flameholders, one single cavity flameholder and two tandem cavity flameholders, were used in experiments. For the two combustors with tandem cavity flameholders, the location and configurations of its up-stream cavity were same with the single cavity flameholder, and the length-to-depth ratios for down-stream cavities were 9 and 11 respectively. The experimental results showed that stabilize kerosene combustion were achieved for combustor with tandem cavity flameholders mounted, and none for that with single cavity flameholder. The none-reacting and reacting flows of combustor models with tandem cavity flameholders were compared and studied with numerical and experimental results. The results showed that higher combustion efficiencies and pressure recovery ratios were achieved for the combustor with down-stream cavity length-to-depth ratio of 9.
Low cost impulse compatible wideband antenna
Rosenbury, Erwin T.; Burke, Gerald J.; Nelson, Scott D.; Stever, Robert D.; Governo, George K.; Mullenhoff, Donald J.
2002-01-01
An antenna apparatus and method for building the antenna is disclosed. Impulse signals travel through a feed point of the antenna with respect to a ground plane. A geometric fin structure is connected to the feed point, and through a termination resistance to the ground plane. A geometric ridge structure connected to the ground is positioned with respect to the fin in order to receive and radiate electromagnetic energy from the impulse signal at a predetermined impedance and over a predetermined set of frequencies. The fin and ridge can be either a wire or a planar surface. The fin and ridge may be disposed within a radiation cavity such as a horn. The radiation cavity is constructed of stamped and etched metal sheets bent and then soldered together. The fin and ridge are also formed from metal sheets or wires. The fin is attached to the feed point and then to the cavity through a termination resistance. The ridge is attached to the cavity and disposed with respect to the fin in order to achieve a particular set of antenna characteristics.
NASA Astrophysics Data System (ADS)
Mohamed, Abdel-Baset A.
2018-04-01
In this paper, some non-classical correlations are investigated for bipartite partitions of two qubits trapped in two spatially separated cavities connected by an optical fiber. The results show that the trace distance discord and Bell's non-locality introduce other quantum correlations beyond the entanglement. Moreover, the correlation functions of the trace distance discord and the Bell's non-locality are very sensitive to the initial correlations, the coupling strengths, and the dissipation rates of the cavities. The fluctuations of the correlation functions between their initial values and gained (loss) values appear due to the unitary evolution of the system. These fluctuations depend on the chosen initial correlations between the two subsystems. The maximal violations of Bell's inequality occur when the logarithmic negativity and the trace distance discord reach certain values. It is shown that the robustness of the non-classical correlations, against the dissipation rates of the cavities, depends on the bipartite partitions reduced density matrices of the system, and is also greatly enhanced by choosing appropriate coupling strengths.
Tian, Feng; Sumikura, Hisashi; Kuramochi, Eiichi; Taniyama, Hideaki; Takiguchi, Masato; Notomi, Masaya
2016-11-28
Optomechanical control of on-chip emitters is an important topic related to integrated all-optical circuits. However, there is neither a realization nor a suitable optomechanical structure for this control. The biggest obstacle is that the emission signal can hardly be distinguished from the pump light because of the several orders' power difference. In this study, we designed and experimentally verified an optomechanical oscillation system, in which a lumped mechanical oscillator connected two optically isolated pairs of coupled one-dimensional photonic crystal cavities. As a functional device, the two pairs of coupled cavities were respectively used as an optomechanical pump for the lumped oscillator (cavity pair II, wavelengths were designed to be within a 1.5 μm band) and a modulation target of the lumped oscillator (cavity pair I, wavelengths were designed to be within a 1.2 μm band). By conducting finite element method simulations, we found that the lumped-oscillator-supported configurations of both cavity pairs enhance the optomechanical interactions, especially for higher order optical modes, compared with their respective conventional side-clamped configurations. Besides the desired first-order in-plane antiphase mechanical mode, other mechanical modes of the lumped oscillator were investigated and found to possibly have optomechanical applications with a versatile degree of freedom. In experiments, the oscillator's RF spectra were probed using both cavity pairs I and II, and the results matched those of the simulations. Dynamic detuning of the optical spectrum of cavity pair I was then implemented with a pumped lumped oscillator. This was the first demonstration of an optomechanical lumped oscillator connecting two optically isolated pairs of coupled cavities, whose biggest advantage is that one cavity pair can be modulated with an lumped oscillator without interference from the pump light in the other cavity pair. Thus, the oscillator is a suitable platform for optomechanical control of integrated lasers, cavity quantum electrodynamics, and spontaneous emission. Furthermore, this device may open the door on the study of interactions between photons, phonons, and excitons in the quantum regime.
Taggar, Amandeep; MacKenzie, Joanna; Li, Haocheng; Lau, Harold; Lim, Gerald; Nordal, Robert; Hudson, Alana; Khan, Rao; Spencer, David; Voroney, Jon-Paul
2016-05-17
To audit outcomes after introducing frameless stereotactic radiosurgery (SRS) for brain metastases, including co-interventions: neurosurgery, systemic therapy, and whole brain radiotherapy (WBRT). We report median overall survival (MS), local failure, and distant brain failure. We hypothesized patients treated with SRS would have clinically meaningful improved MS compared with historic institutional values. We further hypothesized that patients treated with co-interventions would have clinically meaningful improved MS compared with patients treated with SRS alone. One hundred twenty patients (N = 120) with limited intracranial disease underwent 130 frameless SRS sessions from April 2010 to May 2013. Median follow-up was 11 months. MS was measured from brain metastases diagnosis, local failure, and distant brain failure from the time of first SRS. Practice pattern during the first year of the study favored upfront WBRT (79%) over SRS (21%) while upfront SRS (45%) was almost as common as upfront WBRT (55%) in the last year of the study. MS was 18 months; 37% received SRS alone as initial radiotherapy (MS 12 months); 63% received WBRT prior to SRS (MS 19 months); 50% received systemic therapy post-SRS (MS 21 months); and 26% had tumor resection then SRS to the surgical cavity (MS 42 months). Local failure occurred in 10% of lesions and radio-necrosis occurred in 4%. Differences in distant brain failure among patients treated with upfront SRS (40% rate), WBRT followed by SRS (33% rate) or systemic therapy post-SRS (37% rate) were not statistically significant. Frameless SRS effectively treats surgical cavities, persistent tumors post-WBRT, and can be used as an upfront treatment of brain metastases. Surgery, systemic therapy, and WBRT are associated with longer MS. Patients can live for years while receiving multiple therapies. Systemic therapy for patients with brain metastases is increasingly common, palliative care occurs earlier and improves survival, and WBRT use is not routine. Modern series sometimes produce unexpectedly good results. Classification and treatment protocols are evolving. This practice audit is note-worthy for (i) high median overall survival, (ii) systemic therapy after radiosurgery for patients with tumors treated by radiosurgery, (iii) distant brain failure not significantly related to WBRT, and (iv) neurosurgery, systemic therapy, and WBRT are independently associated with improved MS.
Cerutti, Aude; Jauneau, Alain; Auriac, Marie-Christine; Lauber, Emmanuelle; Martinez, Yves; Chiarenza, Serge
2017-01-01
Hydathodes are water pores found on leaves of a wide range of vascular plants and are the sites of guttation. We report here on the detailed anatomy of cauliflower (Brassica oleracea) and Arabidopsis (Arabidopsis thaliana) hydathodes. Hydathode surface presents pores resembling stomata giving access to large cavities. Beneath, the epithem is composed of a lacunar and highly vascularized parenchyma offering a direct connection between leaf surface and xylem vessels. Arabidopsis hydathode pores were responsive to ABA and light similar to stomata. The flg22 flagellin peptide, a well-characterized elicitor of plant basal immunity, did not induce closure of hydathode pores in contrast to stomata. Because hydathodes are natural infection routes for several pathogens, we investigated hydathode infection by the adapted vascular phytopathogenic bacterium Xanthomonas campestris pv campestris (Xcc), the causal agent of black rot disease of Brassicaceae. Microscopic observations of hydathodes six days postinoculation indicated a digestion of the epithem cells and a high bacterial multiplication. Postinvasive immunity was shown to limit pathogen growth in the epithem and is actively suppressed by the type III secretion system and its effector proteins. Altogether, these results give a detailed anatomic description of Brassicaceae hydathodes and highlight the efficient use of this tissue as an initial niche for subsequent vascular systemic dissemination of Xcc in distant plant tissues. PMID:28184011
Reviewing and Reconsidering Invasion Assays in Head and Neck Cancer
Inglehart, Ronald C.; Scanlon, Christina S.; D’Silva, Nisha J.
2014-01-01
Head and neck squamous cell carcinomas (HNSCC) are malignant tumors that arise from the surface epithelium of the oral cavity, oropharynx and larynx, primarily due to exposure to chemical carcinogens or the human papilloma virus. Due to their location, dental practitioners are well-positioned to detect the lesions. Deadlier than lymphoma or melanoma, HNSCC is incompletely understood. For these reasons, dental practitioners and researchers are focused on understanding HNSCC and the processes driving it. One of these critical processes is invasion, the degradation of the basement membrane by HNSCC cells with subsequent movement into the underlying connective tissue, blood vessels or nerves. Cancer cells metastasize to distant sites via the blood vessels, lymphatics and nerves. Metastasis is associated with poor survival. Since invasion is essential for development and metastasis of HNSCC, it is essential to understand the mechanism(s) driving this process. Elucidation of the mechanisms involved will facilitate the development of targeted treatment, thereby accelerating development of precision/ personalized medicine to treat HNSCC. Robust in vitro and in vivo assays are required to investigate the mechanistic basis of invasion. This review will focus on in vitro and in vivo assays used to study invasion in HNSCC, with special emphasis on some of the latest assays to study HNSCC. PMID:25448226
Fluid pump having magnetic drive
Phillips, Benjamin A.; Roeder, Jr., John; Harvey, Michael N.
1996-10-15
A pump includes a housing defining a cavity, an axial bore coaxially communicating with the cavity, at least one radial bore radially extending between the cavity and an outlet, and an inlet communicating with the radial bore intermediate to the cavity and the outlet. A crankshaft having a longitudinal axis is disposed in the axial bore for rotation about the axis and includes an eccentric portion disposed in the cavity. A piston having a base is disposed in the cavity, and has a head disposed in the radial bore for slidable reciprocation between a discharge position proximate the outlet and an intake position at the inlet between the cavity and the outlet. A cage structure including a cage and a slider block connects the piston base to the eccentric portion of the crankshaft for transforming rotation of the eccentric portion in the cavity to reciprocation of the piston in the radial bore. A valve structure opens and closes the outlet in response to movement of the piston head between the discharge position to the intake position.
Loading a single photon into an optical cavity
NASA Astrophysics Data System (ADS)
Du, Shengwang; Liu, Chang; Sun, Yuan; Zhao, Luwei; Zhang, Shanchao; Loy, M. M. T.
2015-05-01
Confining and manipulating single photons inside a reflective optical cavity is an essential task of cavity quantum electrodynamics (CQED) for probing the quantum nature of light quanta. Such systems are also elementary building blocks for many protocols of quantum network, where remote cavity quantum nodes are coupled through flying photons. The connectivity and scalability of such a quantum network strongly depends on the efficiency of loading a single photon into cavity. In this work we demonstrate that a single photon with an optimal temporal waveform can be efficiently loaded into a cavity. Using heralded narrow-band single photons with exponential growth wave packet whose time constant matches the photon lifetime in the cavity, we demonstrate a loading efficiency of more than 87 percent from free space to a single-sided Fabry-Perot cavity. Our result and approach may enable promising applications in realizing large-scale CQED-based quantum networks. The work was supported by the Hong Kong RGC (Project No. 601411).
Fritz, Robert J.
1986-01-01
A flowmeter is provided which uses the sidetones generated in a cavity formed in the wall of a flowpipe or the like in response to fluid flowing past the cavity to provide a measure of the flow velocity of that fluid. The dimensions of the cavity are such as to provide a dominant vibratory frequency which is sensed by a pressure sensor. The flowmeter is adapted for use for a range of frequencies in which the Strouhal number is constant and under these conditions the vibratory frequency is directly related to the flow rate. The tone generator cavity and pressure transducer form a unit which is connected in-line in the flowpipe.
Fritz, R.J.
1983-11-03
A flowmeter is provided which uses the sidetones generated in a cavity formed in the wall of a flowpipe or the like in response to fluid flowing past the cavity to provide a measure of the flow velocity of that fluid. The dimensions of the cavity are such as to provide a dominant vibratory frequency which is sensed by a pressure sensor. The flowmeter is adapted for use for a range of frequencies in which the Strouhal number is constant and under these conditions the vibratory frequency is directly related to the flow rate. The tone generator cavity and pressure transducer form a unit which is connected in-line in the flowpipe.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi, Clara Y.H.; Chang, Steven D.; Gibbs, Iris C.
2012-10-01
Purpose: Given the neurocognitive toxicity associated with whole-brain irradiation (WBRT), approaches to defer or avoid WBRT after surgical resection of brain metastases are desirable. Our initial experience with stereotactic radiosurgery (SRS) targeting the resection cavity showed promising results. We examined the outcomes of postoperative resection cavity SRS to determine the effect of adding a 2-mm margin around the resection cavity on local failure (LF) and toxicity. Patients and Methods: We retrospectively evaluated 120 cavities in 112 patients treated from 1998-2009. Factors associated with LF and distant brain failure (DF) were analyzed using competing risks analysis, with death as a competingmore » risk. The overall survival (OS) rate was calculated by the Kaplan-Meier product-limit method; variables associated with OS were evaluated using the Cox proportional hazards and log rank tests. Results: The 12-month cumulative incidence rates of LF and DF, with death as a competing risk, were 9.5% and 54%, respectively. On univariate analysis, expansion of the cavity with a 2-mm margin was associated with decreased LF; the 12-month cumulative incidence rates of LF with and without margin were 3% and 16%, respectively (P=.042). The 12-month toxicity rates with and without margin were 3% and 8%, respectively (P=.27). On multivariate analysis, melanoma histology (P=.038) and number of brain metastases (P=.0097) were associated with higher DF. The median OS time was 17 months (range, 2-114 months), with a 12-month OS rate of 62%. Overall, WBRT was avoided in 72% of the patients. Conclusion: Adjuvant SRS targeting the resection cavity of brain metastases results in excellent local control and allows WBRT to be avoided in a majority of patients. A 2-mm margin around the resection cavity improved local control without increasing toxicity compared with our prior technique with no margin.« less
Suárez, Carlos; Barnes, Leon; Silver, Carl E.; Rodrigo, Juan P.; Shah, Jatin P.; Triantafyllou, Asterios; Rinaldo, Alessandra; Cardesa, Antonio; Pitman, Karen T.; Kowalski, Luiz P.; Robbins, K. Thomas; Hellquist, Henrik; Medina, Jesus E.; de Bree, Remco; Takes, Robert P.; Coca-Pelaz, Andrés; Bradley, Patrick J.; Gnepp, Douglas R.; Teymoortash, Afshin; Strojan, Primož; Mendenhall, William M.; Eloy, Jean Anderson; Bishop, Justin A.; Devaney, Kenneth O.; Thompson, Lester D.R.; Hamoir, Marc; Slootweg, Pieter J.; Poorten, Vincent Vander; Williams, Michelle D.; Wenig, Bruce M.; Skálová, Alena; Ferlito, Alfio
2016-01-01
The purpose of this study was to establish general guidelines in the management of the N0 neck of oral cavity and oropharyngeal adenoid cystic carcinoma (AdCC) in order to improve the survival of these patients and/or reduce the risk of neck recurrences. The incidence of cervical node metastasis at diagnosis of head and neck AdCC is variable, and ranges between 3% and 16%. Metastasis to the cervical lymph nodes of intraoral and oropharyngeal AdCC varies from 2% to 43%, with the lower rates pertaining to palatal AdCC and the higher rates to base of the tongue. Neck node recurrence may happen after treatment in 0–14% of AdCC, is highly dependent on the extent of the treatment and is very rare in patients who have been treated with therapeutic or elective neck dissections, or elective neck irradiation. Lymph node involvement with or without extracapsular extension in AdCC has been shown in most reports to be independently associated with decreased overall and cause-specific survival, probably because lymph node involvement is a risk factor for subsequent distant metastasis. The overall rate of occult neck metastasis in patients with head and neck AdCC ranges from 15% to 44%, but occult neck metastasis from oral cavity and/or oropharynx seems to occur more frequently than from other locations such as the sinonasal tract and major salivary glands. Nevertheless, the benefit of elective neck dissection (END) in AdCC is not comparable to that of squamous cell carcinoma, because the main cause of failure is not related to neck or local recurrence, but rather, to distant failure. Therefore, END should be considered in patients with a cN0 neck with AdCC in some high risk oral and oropharyngeal locations when postoperative RT is not planned, or the rare AdCC-high grade transformation. PMID:27017314
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dirix, Piet; Nuyts, Sandra; Geussens, Yasmyne
Purpose: To evaluate the long-term clinical outcome and toxicity of conventional and three-dimensional conformal radiotherapy for malignancies of the nasal cavity and paranasal sinuses. Methods and Materials: Between January 1976 and February 2003, 127 patients with histologically proven cancer of the paranasal sinuses (n = 119) or nasal cavity (n = 8) were treated with preoperative (n = 61), postoperative (n = 51), or primary (n = 15) radiotherapy, using conventional (n = 74) or three-dimensional conformal (n = 53) techniques. No elective neck irradiation of the cervical lymph nodes was performed in N0 patients. Results: Median follow-up was 5.6more » years (range, 3-307 months) for all patients, and 7.3 years (range, 47-307 months) for patients still alive at the close-out date. The actuarial 5-year local control, overall survival, and disease-free survival rates were 53%, 54%, and 37%, respectively. Only 6 (5%) of all 127 patients and 4 (3%) of 122 originally N0 patients developed a regional failure in the neck. Distant metastasis occurred in 20% of patients. Both primary tumor extent and lymph node involvement were the most important prognostic factors, together with squamous cell carcinoma histology. Conclusion: Local failure remains the dominant cause of poor outcome for patients with sinonasal cancer, despite aggressive local treatment with combined surgery and radiotherapy in operable patients. Distant metastasis and certainly regional relapse were much less common sites of failure. Overall survival remains poor, suggesting the need for more efficacious local and possibly systemic therapy.« less
Sarcomas of nasal cavity and paranasal sinuses: chondrosarcoma, osteosarcoma and fibrosarcoma.
Koka, V; Vericel, R; Lartigau, E; Lusinchi, A; Schwaab, G
1994-11-01
Forty-two patients were treated for sarcoma of the nasal cavity and paranasal sinuses at the Institut Gustave Roussy, Paris, between 1960 and 1993. Twelve patients had chondrosarcoma (CS), 14 had osteosarcoma (OS) and 16 had fibrosarcoma (FS). Ten patients had grade I, six grade II and 26 grade III tumours. All but 10 patients had surgery for the primary tumour. A significantly increased risk of local failure was associated with the male sex (p < 0.01), grade III tumours (p < 0.02) and patients excluded from surgery (p < 0.04). The overall incidence of local and distant failure was 76 and 12 per cent respectively. Overall survival was 28 per cent at three years and 23 per cent at five years. Eight patients (20 per cent) were alive more than 10 years later. The factors significantly influencing survival were sex (p < 0.01), grade (p < 0.05) and local failure (p < 0.01).
Molecular evolution of gas cavity in [NiFeSe] hydrogenases resurrected in silico
NASA Astrophysics Data System (ADS)
Tamura, Takashi; Tsunekawa, Naoki; Nemoto, Michiko; Inagaki, Kenji; Hirano, Toshiyuki; Sato, Fumitoshi
2016-01-01
Oxygen tolerance of selenium-containing [NiFeSe] hydrogenases (Hases) is attributable to the high reducing power of the selenocysteine residue, which sustains the bimetallic Ni-Fe catalytic center in the large subunit. Genes encoding [NiFeSe] Hases are inherited by few sulphate-reducing δ-proteobacteria globally distributed under various anoxic conditions. Ancestral sequences of [NiFeSe] Hases were elucidated and their three-dimensional structures were recreated in silico using homology modelling and molecular dynamic simulation, which suggested that deep gas channels gradually developed in [NiFeSe] Hases under absolute anaerobic conditions, whereas the enzyme remained as a sealed edifice under environmental conditions of a higher oxygen exposure risk. The development of a gas cavity appears to be driven by non-synonymous mutations, which cause subtle conformational changes locally and distantly, even including highly conserved sequence regions.
Dissipation induced asymmetric steering of distant atomic ensembles
NASA Astrophysics Data System (ADS)
Cheng, Guangling; Tan, Huatang; Chen, Aixi
2018-04-01
The asymmetric steering effects of separated atomic ensembles denoted by the effective bosonic modes have been explored by the means of quantum reservoir engineering in the setting of the cascaded cavities, in each of which an atomic ensemble is involved. It is shown that the steady-state asymmetric steering of the mesoscopic objects is unconditionally achieved via the dissipation of the cavities, by which the nonlocal interaction occurs between two atomic ensembles, and the direction of steering could be easily controlled through variation of certain tunable system parameters. One advantage of the present scheme is that it could be rather robust against parameter fluctuations, and does not require the accurate control of evolution time and the original state of the system. Furthermore, the double-channel Raman transitions between the long-lived atomic ground states are used and the atomic ensembles act as the quantum network nodes, which makes our scheme insensitive to the collective spontaneous emission of atoms.
Update on primary head and neck mucosal melanoma
López, Fernando; Rodrigo, Juan P.; Cardesa, Antonio; Triantafyllou, Asterios; Devaney, Kenneth O.; Mendenhall, William M.; Haigentz, Missak; Strojan, Primož; Pellitteri, Phillip K.; Bradford, Carol R.; Shaha, Ashok R.; Hunt, Jennifer L.; de Bree, Remco; Takes, Robert P.; Rinaldo, Alessandra; Ferlito, Alfio
2016-01-01
Primary mucosal melanomas (PMMs) of the head and neck are uncommon malignancies that arise mainly in the nasal cavity and paranasal sinuses, followed by the oral cavity. The mainstay of treatment is radical surgical resection followed by adjuvant radiotherapy in selected patients with high-risk features. Multimodality therapy has not been well studied and is not standardized. Adjuvant radiotherapy seems to improve locoregional control but does not improve overall survival (OS). Elective neck dissection is advocated in patients with oral PMM. Systemic therapy should be considered only for patients with metastatic or unresectable locoregional disease. Despite improvements in the field of surgery, radiotherapy, and systemic therapy, patients with PMM still face a very unfavorable prognosis (5-year disease-free survival [DFS] <20%) with high rates of locoregional recurrence and distant metastasis. The present review aims to summarize the current state of knowledge on the molecular biology, pathological diagnosis, and management of this disease. PMID:25242350
Kerley, P.L.
1959-01-01
A small-size antenna having a doughnut-shaped field pattern and which can act both as an antenna and a resonant circuit is described. The antenna is of the slotted type and comprises a resonant cavity with a center hole. A circular slot is provided in one wall of the cavity concentric with the hole and a radio frequency source is connected across the slot. The pattern and loading of the antenna are adjusted by varying the position and shape of a center element slidably disposed within the hole and projecting from the slotted side of the resonant cavity. The disclosed structure may also be used to propagate the oscillator signal down a transniission line by replacing the center element with one leg of the transmission line in a spaced relation from the walls of the cavity.
Cavity-backed, micro-strip dipole antenna array
NASA Technical Reports Server (NTRS)
Ellis, H., Jr. (Inventor)
1981-01-01
A flush-mounted antenna assembly includes a generally rectangular, conductive, box structure open along one face to form a cavity. Within the cavity a pair of mutually orthogonal dielectric plane surfaces in an "egg crate" arrangement are mounted normal to the plane of the open face, each diagonally within the cavity. Each dielectric plane supports a pair of printed circuit dipoles typically each fed from the opposite side of the dielectric plane by a printed "cone-shaped" feed line trace which also serve as an impedance matching device and functions as a balun connected from an unbalanced strip line external feed. The open face of the conductive cavity can be flush mounted with a randome thereover, the assembly thereby being flush with the skin of a aircraft or space vehicle.
Cavity-backed, micro-strip dipole antenna array
NASA Astrophysics Data System (ADS)
Ellis, H., Jr.
1981-09-01
A flush-mounted antenna assembly includes a generally rectangular, conductive, box structure open along one face to form a cavity. Within the cavity a pair of mutually orthogonal dielectric plane surfaces in an "egg crate" arrangement are mounted normal to the plane of the open face, each diagonally within the cavity. Each dielectric plane supports a pair of printed circuit dipoles typically each fed from the opposite side of the dielectric plane by a printed "cone-shaped" feed line trace which also serve as an impedance matching device and functions as a balun connected from an unbalanced strip line external feed. The open face of the conductive cavity can be flush mounted with a randome thereover, the assembly thereby being flush with the skin of a aircraft or space vehicle.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Webb, Aaron P.; Carlson, Charles T.; Weaver, William T.
A mask alignment system for providing precise and repeatable alignment between ion implantation masks and workpieces. The system includes a mask frame having a plurality of ion implantation masks loosely connected thereto. The mask frame is provided with a plurality of frame alignment cavities, and each mask is provided with a plurality of mask alignment cavities. The system further includes a platen for holding workpieces. The platen may be provided with a plurality of mask alignment pins and frame alignment pins configured to engage the mask alignment cavities and frame alignment cavities, respectively. The mask frame can be lowered ontomore » the platen, with the frame alignment cavities moving into registration with the frame alignment pins to provide rough alignment between the masks and workpieces. The mask alignment cavities are then moved into registration with the mask alignment pins, thereby shifting each individual mask into precise alignment with a respective workpiece.« less
Beam steering via resonance detuning in coherently coupled vertical cavity laser arrays
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, Matthew T., E-mail: matthew.johnson.9@us.af.mil; Siriani, Dominic F.; Peun Tan, Meng
2013-11-11
Coherently coupled vertical-cavity surface-emitting laser arrays offer unique advantages for nonmechanical beam steering applications. We have applied dynamic coupled mode theory to show that the observed temporal phase shift between vertical-cavity surface-emitting array elements is caused by the detuning of their resonant wavelengths. Hence, a complete theoretical connection between the differential current injection into array elements and the beam steering direction has been established. It is found to be a fundamentally unique beam-steering mechanism with distinct advantages in efficiency, compactness, speed, and phase-sensitivity to current.
Huang, Xiao-Bin; Chen, Ye-Hong; Wang, Zhe
2016-05-24
In this paper, we propose an efficient scheme to fast generate three-qubit Greenberger-Horne-Zeilinger (GHZ) state by constructing shortcuts to adiabatic passage (STAP) based on the "Lewis-Riesenfeld (LR) invariants" in spatially separated cavities connected by optical fibers. Numerical simulations illustrate that the scheme is not only fast, but robust against the decoherence caused by atomic spontaneous emission, cavity losses and the fiber photon leakages. This might be useful to realize fast and noise-resistant quantum information processing for multi-qubit systems.
Parametric resonance in tunable superconducting cavities
NASA Astrophysics Data System (ADS)
Wustmann, Waltraut; Shumeiko, Vitaly
2013-05-01
We develop a theory of parametric resonance in tunable superconducting cavities. The nonlinearity introduced by the superconducting quantum interference device (SQUID) attached to the cavity and damping due to connection of the cavity to a transmission line are taken into consideration. We study in detail the nonlinear classical dynamics of the cavity field below and above the parametric threshold for the degenerate parametric resonance, featuring regimes of multistability and parametric radiation. We investigate the phase-sensitive amplification of external signals on resonance, as well as amplification of detuned signals, and relate the amplifier performance to that of linear parametric amplifiers. We also discuss applications of the device for dispersive qubit readout. Beyond the classical response of the cavity, we investigate small quantum fluctuations around the amplified classical signals. We evaluate the noise power spectrum both for the internal field in the cavity and the output field. Other quantum-statistical properties of the noise are addressed such as squeezing spectra, second-order coherence, and two-mode entanglement.
Efthimion, Philip C.; Helfritch, Dennis J.
1989-11-28
An apparatus and method for creating high temperature plasmas for enhanced chemical processing of gaseous fluids, toxic chemicals, and the like, at a wide range of pressures, especially at atmospheric and high pressures includes an electro-magnetic resonator cavity, preferably a reentrant cavity, and a wave guiding structure which connects an electro-magnetic source to the cavity. The cavity includes an intake port and an exhaust port, each having apertures in the conductive walls of the cavity sufficient for the intake of the gaseous fluids and for the discharge of the processed gaseous fluids. The apertures are sufficiently small to prevent the leakage of the electro-magnetic radiation from the cavity. Gaseous fluid flowing from the direction of the electro-magnetic source through the guiding wave structure and into the cavity acts on the plasma to push it away from the guiding wave structure and the electro-magnetic source. The gaseous fluid flow confines the high temperature plasma inside the cavity and allows complete chemical processing of the gaseous fluids at a wide range of pressures.
High reflected cubic cavity as long path absorption cell for infrared gas sensing
NASA Astrophysics Data System (ADS)
Yu, Jia; Gao, Qiang; Zhang, Zhiguo
2014-10-01
One direct and efficient method to improve the sensitivity of infrared gas sensors is to increase the optical path length of gas cells according to Beer-Lambert Law. In this paper, cubic shaped cavities with high reflected inner coating as novel long path absorption cells for infrared gas sensing were developed. The effective optical path length (EOPL) for a single cubic cavity and tandem cubic cavities were investigated based on Tunable Diode Laser Absorption Spectroscopy (TDLAS) measuring oxygen P11 line at 763 nm. The law of EOPL of a diffuse cubic cavity in relation with the reflectivity of the coating, the port fraction and side length of the cavity was obtained. Experimental results manifested an increase of EOPL for tandem diffuse cubic cavities as the decrease of port fraction of the connecting aperture f', and the EOPL equaled to the sum of that of two single cubic cavities at f'<0.01. The EOPL spectra at infrared wavelength range for different inner coatings including high diffuse coatings and high reflected metallic thin film coatings were deduced.
Dutta, Pinaki R; Riaz, Nadeem; McBride, Sean; Morris, Luc G; Patel, Snehal; Ganly, Ian; Wong, Richard J; Palmer, Frank; Schöder, Heiko; Lee, Nancy
2016-04-01
The purpose of this study was for us to present our evaluation of the effectiveness of positron emission tomography (PET)/CT imaging in postoperative patients with oral cavity squamous cell carcinoma (SCC) before initiating adjuvant radiation therapy. Treatment planning PET/CT scans were obtained in 44 patients with oral cavity SCC receiving adjuvant radiation. We identified target areas harboring macroscopic disease requiring higher radiation doses or additional surgery. Fourteen PET/CT scans were abnormal. Thirteen patients underwent surgery and/or biopsy, increased radiation dose, and/or addition of chemotherapy. Eleven patients received higher radiation doses. Patients undergoing imaging >8 weeks were more likely to have abnormal results (p = .01). One-year distant metastases-free survival was significantly worse in patients with positive PET/CT scans (61.5% vs 92.7%; p = .01). The estimated positive predictive value (PPV) was 38% for postoperative PET/CT scanning. We demonstrated that 32% of patients have abnormal PET/CT scans resulting in management changes. Patients may benefit from postoperative PET/CT imaging to optimize adjuvant radiation treatment planning. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1285-E1293, 2016. © 2015 Wiley Periodicals, Inc.
Hermetic fiber optic-to-metal connection technique
Kramer, Daniel P.
1992-09-01
A glass-to-glass hermetic sealing technique is disclosed which can be used to splice lengths of glass fibers together. A solid glass preform is inserted into the cavity of a metal component which is then heated to melt the glass. An end of an optical fiber is then advanced into the molten glass and the entire structure cooled to solidify the glass in sealing engagement with the optical fiber end and the metal cavity. The surface of the re-solidified glass may be machined for mating engagement with another component to make a spliced fiber optic connection. The resultant structure has a helium leak rate of less than 1.times.10.sup.-8 cm.sup.3 /sec.
NASA Astrophysics Data System (ADS)
Antoniuk, Oleg; Sprik, Rudolf
2010-03-01
We developed a random matrix model to describe the statistics of resonances in an acoustic cavity with broken time-reversal invariance. Time-reversal invariance braking is achieved by connecting an amplified feedback loop between two transducers on the surface of the cavity. The model is based on approach [1] that describes time- reversal properties of the cavity without a feedback loop. Statistics of eigenvalues (nearest neighbor resonance spacing distributions and spectral rigidity) has been calculated and compared to the statistics obtained from our experimental data. Experiments have been performed on aluminum block of chaotic shape confining ultrasound waves. [1] Carsten Draeger and Mathias Fink, One-channel time- reversal in chaotic cavities: Theoretical limits, Journal of Acoustical Society of America, vol. 105, Nr. 2, pp. 611-617 (1999)
32 CFR 199.13 - TRICARE Dental Program.
Code of Federal Regulations, 2011 CFR
2011-07-01
..., beneficiary pre-authorization and marketing procedures, and care for beneficiaries residing in distant areas... examinations; and (iii) Diagnostic laboratory tests and examinations provided in connection with other dental...) Initial determination. A formal written decision on a TDP claim, a request for TDP benefit pre...
32 CFR 199.13 - TRICARE Dental Program.
Code of Federal Regulations, 2010 CFR
2010-07-01
..., beneficiary pre-authorization and marketing procedures, and care for beneficiaries residing in distant areas... examinations; and (iii) Diagnostic laboratory tests and examinations provided in connection with other dental...) Initial determination. A formal written decision on a TDP claim, a request for TDP benefit pre...
Method for forming cooperative binary ionic solids
Shelnutt, John A.; Martin, Kathleen E.; Wang, Zhongchun; Medforth, Craig J.
2013-03-05
A nanostructured molecular unit and method for forming is described where a cationic porphyrin having an ethanolic substituent species and a metal in the porphyrin cavity is combined with an anionic porphyrin having a sulfonate substituent species and a metal in the porphyrin cavity to form by self-assembly a nanostructured molecular unit with a morphology comprising four dendritic elements connected at a central node.
Method for forming cooperative binary ionic solids
Shelnutt, John A.; Martin, Kathleen E.; Wang, Zhongchun; Medforth, Craig J.
2014-09-09
A nanostructured molecular unit and method for forming is described where a cationic porphyrin having an ethanolic substituent species and a metal in the porphyrin cavity is combined with an anionic porphyrin having a sulfonate substituent species and a metal in the porphyrin cavity to form by self-assembly a nanostructured molecular unit with a morphology comprising four dendritic elements connected at a central node.
Detachable connection for a nuclear reactor fuel assembly
Christiansen, D.W.; Karnesky, R.A.
1983-08-29
A locking connection for releasably attaching a handling socket to the duct tube of a fuel assembly for a nuclear reactor. The connection comprises a load pad housing mechanically attached to the duct tube and a handling socket threadably secured within the housing. A retaining ring is interposed between the housing and the handling socket and is formed with a projection and depression engagable within a cavity and groove of the housing and handling socket, respectively, to form a detachable interlocked connection assembly.
Detachable connection for a nuclear reactor fuel assembly
Christiansen, David W.; Karnesky, Richard A.
1986-01-01
A locking connection for releasably attaching a handling socket to the duct tube of a fuel assembly for a nuclear reactor. The connection comprises a load pad housing mechanically attached to the duct tube and a handling socket threadably secured within the housing. A retaining ring is interposed between the housing and the handling socket and is formed with a projection and depression engageable within a cavity and groove of the housing and handling socket, respectively, to form a detachable interlocked connection assembly.
Comparison of higher order modes damping techniques for 800 MHz single cell superconducting cavities
NASA Astrophysics Data System (ADS)
Shashkov, Ya. V.; Sobenin, N. P.; Petrushina, I. I.; Zobov, M. M.
2014-12-01
At present, applications of 800 MHz harmonic cavities in both bunch lengthening and shortening regimes are under consideration and discussion in the framework of the High Luminosity LHC project. In this paper we study electromagnetic characteristics of high order modes (HOMs) for a single cell 800 MHz superconducting cavity and arrays of such cavities connected by drifts tubes. Different techniques for the HOMs damping such as beam pipe grooves, coaxial-notch loads, fluted beam pipes etc. are investigated and compared. The influence of the sizes and geometry of the drift tubes on the HOMs damping is analyzed. The problems of a multipacting discharge in the considered structures are discussed and the operating frequency detuning due to the Lorentz force is evaluated.
Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes
Palmer, Robert B.
1991-01-01
An accelerating cavity having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps.
The Connection Between Solar Coronal Cavities and Solar Filaments
NASA Astrophysics Data System (ADS)
Zawadzki, B.; Karna, N.; Prchlik, J.; Reeves, K.; Kempton, D.; Angryk, R.
2017-12-01
Filaments are structures in the solar corona made up of relatively cool, dense, partially ionized plasma. Coronal cavities, circular or elliptical regions of low plasma density, are observed above prominences on the solar limb when viewed in EUV and white light coronal images. Since most filament/cavity eruptions lead to a coronal mass ejection (CME), determining the likelihood of an eruption event will improve our ability to predict space weather. We examine SDO/AIA cavity metadata and HEK filament metadata to determine which cavities are associated with which filaments from 2012 to 2015. Our study involved 140 cavities and 368 filaments that appeared poleward of +-30 degrees. We categorized the cavities and filaments based on the stability of the structures, defined by whether or not the cavity and filament exist long enough to track fully across the solar disk. Using these categories we perform a statistical study on various filament qualities within the metadata. Our findings indicate that filaments with cavities are observed more often at high latitude in compared to filaments without cavities. Moreover, our study indicates that a statistically significant difference exists between the filament length and tilt distributions for certain categories. This work supported by the NSF-REU solar physics program at SAO, grant number AGS-1560313, and the NSF-DIBBS project, grant number ACI-1443061.
Code of Federal Regulations, 2014 CFR
2014-10-01
... button or radio control when such switch is protected by distant switch indicators, switch point... units are connected so that they may be operated from a single control stand. Locomotive means, for... one or more propelling motors designed for moving other equipment; (2) With one or more propelling...
Time evolution of the one-dimensional Jaynes-Cummings-Hubbard Hamiltonian
DOE Office of Scientific and Technical Information (OSTI.GOV)
Makin, M. I.; Hill, Charles D.; Greentree, Andrew D.
2009-10-15
The Jaynes-Cummings-Hubbard (JCH) system describes a network of single-mode photonic cavities connected via evanescent coupling. Each cavity contains a single two-level system which can be tuned in resonance with the cavity. Here, we explore the behavior of single excitations (where an excitation can be either photonic or atomic) in the linear JCH system, which describes a coupled cavity waveguide. We use direct, analytic diagonalization of the Hamiltonian to study cases where intercavity coupling is either uniform or varies parabolically along the chain. Both excitations located in a single cavity, as well as one excitation as a Gaussian pulse spread overmore » many cavities, are investigated as initial states. We predict unusual behavior of this system in the time domain, including slower than expected propagation of the excitation and also splitting of the excitation into two distinct pulses, which travel at distinct speeds. In certain limits, we show that the JCH system mimics two Heisenberg spin chains.« less
An Experimental Study of Vortex Flow Formation and Dynamics in Confined Microcavities
NASA Astrophysics Data System (ADS)
Khojah, Reem; di Carlo, Dino
2017-11-01
New engineering solutions for bioparticle separation invites revisiting classic fluid dynamics problems. Previous studies investigated cavity vortical flow that occurs in 2D with the formation of a material flux boundary or separatrix between the main flow and cavity flow. We demonstrate the concept of separatrix breakdown, in which the cavity flow becomes connected to the main flow, occurs as the cavity is confined in 3D, and is implicated in particle capture and rapid mass exchange in cavities. Understanding the convective flux between the channel and a side cavity provides insight into size-dependent particle capture and release from the cavity flow. The process of vortex formation and separatrix breakdown between the main channel to the side cavity is Reynolds number dependent and can be described by dissecting the flow streamlines from the main channel that enter and spiral out of the cavity. Laminar streamlines from incremented initial locations in the main flow are observed inside the cavity under different flow conditions. Experimentally, we provide the Reynolds number threshold to generate certain flow geometry. We found the optimal flow conditions that enable rapid convective transfer through the cavity flow and exposure and interaction between soluble factors with captured cells. By tuning which fraction of the main flow has solute, we can create a dynamic gate between the cavity and channel flow that potentially serves as a time-dependent fluid exchange approach for objects within the cavity.
An Ultra-Sensitive Electrometer based on the Cavity-Embedded Cooper-Pair Transistor
NASA Astrophysics Data System (ADS)
Li, Juliang; Miller, Marco; Rimberg, Alex
2015-03-01
We discuss use of a cavity-embedded Cooper-pair transistor (cCPT) as a potentially quantum-limited electrometer. The cCPT consists of a Cooper pair transistor placed at the voltage antinode of a 5.7 GHz shorted quarter-wave resonator so that the CPT provides a galvanic connection between the cavity's central conductor and ground plane. The quantum inductance of the CPT, which appears in parallel with the effective inductance of the cavity resonance, can be modulated by application of either a gate voltage to the CPT island or a flux bias to the CPT/cavity loop. Changes in the CPT inductance shift the cavity resonant frequency, and therefore the phase of a microwave signal reflected from the cavity. The reflected wave is amplified by both SLUG and HEMT amplifiers before its phase is measured. Results of recent measurements on the cCPT electrometer will be compared with theoretical predictions. This work was supported by the NSF under Grant No. DMR-1104821, by the ARO under Contract No, W911NF-13-1-0377 and by AFOSR/DARPA under Agreement No. FA8750-12-2-0339.
Local-Scale Simulations of Nucleate Boiling on Micrometer Featured Surfaces: Preprint
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sitaraman, Hariswaran; Moreno, Gilberto; Narumanchi, Sreekant V
2017-08-03
A high-fidelity computational fluid dynamics (CFD)-based model for bubble nucleation of the refrigerant HFE7100 on micrometer-featured surfaces is presented in this work. The single-fluid incompressible Navier-Stokes equations, along with energy transport and natural convection effects are solved on a featured surface resolved grid. An a priori cavity detection method is employed to convert raw profilometer data of a surface into well-defined cavities. The cavity information and surface morphology are represented in the CFD model by geometric mesh deformations. Surface morphology is observed to initiate buoyancy-driven convection in the liquid phase, which in turn results in faster nucleation of cavities. Simulationsmore » pertaining to a generic rough surface show a trend where smaller size cavities nucleate with higher wall superheat. This local-scale model will serve as a self-consistent connection to larger device scale continuum models where local feature representation is not possible.« less
Local-Scale Simulations of Nucleate Boiling on Micrometer-Featured Surfaces
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sitaraman, Hariswaran; Moreno, Gilberto; Narumanchi, Sreekant V
2017-07-12
A high-fidelity computational fluid dynamics (CFD)-based model for bubble nucleation of the refrigerant HFE7100 on micrometer-featured surfaces is presented in this work. The single-fluid incompressible Navier-Stokes equations, along with energy transport and natural convection effects are solved on a featured surface resolved grid. An a priori cavity detection method is employed to convert raw profilometer data of a surface into well-defined cavities. The cavity information and surface morphology are represented in the CFD model by geometric mesh deformations. Surface morphology is observed to initiate buoyancy-driven convection in the liquid phase, which in turn results in faster nucleation of cavities. Simulationsmore » pertaining to a generic rough surface show a trend where smaller size cavities nucleate with higher wall superheat. This local-scale model will serve as a self-consistent connection to larger device scale continuum models where local feature representation is not possible.« less
Noise switching at a dynamical critical point in a cavity-conductor hybrid
NASA Astrophysics Data System (ADS)
Armour, Andrew D.; Kubala, Björn; Ankerhold, Joachim
2017-12-01
Coupling a mesoscopic conductor to a microwave cavity can lead to fascinating feedback effects which generate strong correlations between the dynamics of photons and charges. We explore the connection between cavity dynamics and charge transport in a model system consisting of a voltage-biased Josephson junction embedded in a high-Q cavity, focusing on the behavior as the system is tuned through a dynamical critical point. On one side of the critical point the noise is strongly suppressed, signaling the existence of a regime of highly coherent transport, but on the other side it switches abruptly to a much larger value. Using a semiclassical approach we show that this behavior arises because of the strongly nonlinear cavity drive generated by the Cooper pairs. We also uncover an equivalence between charge and photonic current noise in the system which opens up a route to detecting the critical behavior through straightforward microwave measurements.
Microwave Detection of Chemical Agents: A Review
1986-06-01
Health (NIOSH).8’l1 This instrument was designed to detect acetonitrile, acetaldehyde , acetone, carbonyl sulfide, ethanol, ethylene oxide , isopropyl...absolute temperature mij - the dipole matrix element connecting the upper and lower energy states vo = the absorption line center v - transition...from multiple reflections through the cell. The Q of a cavity is defined as the electro - magnetic energy in the cavity divided by the energy lost per
Cerutti, Aude; Jauneau, Alain; Auriac, Marie-Christine; Lauber, Emmanuelle; Martinez, Yves; Chiarenza, Serge; Leonhardt, Nathalie; Berthomé, Richard; Noël, Laurent D
2017-06-01
Hydathodes are water pores found on leaves of a wide range of vascular plants and are the sites of guttation. We report here on the detailed anatomy of cauliflower ( Brassica oleracea ) and Arabidopsis ( Arabidopsis thaliana ) hydathodes. Hydathode surface presents pores resembling stomata giving access to large cavities. Beneath, the epithem is composed of a lacunar and highly vascularized parenchyma offering a direct connection between leaf surface and xylem vessels. Arabidopsis hydathode pores were responsive to ABA and light similar to stomata. The flg22 flagellin peptide, a well-characterized elicitor of plant basal immunity, did not induce closure of hydathode pores in contrast to stomata. Because hydathodes are natural infection routes for several pathogens, we investigated hydathode infection by the adapted vascular phytopathogenic bacterium Xanthomonas campestris pv campestris ( Xcc ), the causal agent of black rot disease of Brassicaceae. Microscopic observations of hydathodes six days postinoculation indicated a digestion of the epithem cells and a high bacterial multiplication. Postinvasive immunity was shown to limit pathogen growth in the epithem and is actively suppressed by the type III secretion system and its effector proteins. Altogether, these results give a detailed anatomic description of Brassicaceae hydathodes and highlight the efficient use of this tissue as an initial niche for subsequent vascular systemic dissemination of Xcc in distant plant tissues. © 2017 American Society of Plant Biologists. All Rights Reserved.
Pulmonary nocardiosis in patients with connective tissue disease: A report of two cases
Hagiwara, Shinya; Tsuboi, Hiroto; Hagiya, Chihiro; Yokosawa, Masahiro; Hirota, Tomoya; Ebe, Hiroshi; Takahashi, Hiroyuki; Ogishima, Hiroshi; Asashima, Hiromitsu; Kondo, Yuya; Umeda, Naoto; Suzuki, Takeshi; Hitomi, Shigemi; Matsumoto, Isao; Sumida, Takayuki
2014-01-01
Summary Reported here are 2 patients with connective tissue disease who developed pulmonary nocardiosis. Case 1 involved a 73-year-old man with malignant rheumatoid arthritis treated with prednisolone 25 mg/day. Chest X-rays revealed a pulmonary cavity and bronchoscopy detected Nocardia species. The patient was successfully treated with trimethoprim/sulfamethoxazole. Case 2 involved a 41-year-old woman with systemic lupus erythematosus. The patient received remission induction therapy with 50 mg/day of prednisolone and tacrolimus. Six weeks later, a chest CT scan revealed a pulmonary cavity; bronchoscopy resulted in a diagnosis of pulmonary nocardiosis. The patient had difficulty tolerating trimethoprim/sulfamethoxazole, so she was switched to and successfully treated with imipenem/cilastatin and amikacin. PMID:25343123
Boundary Recovery For Delaunay Tetrahedral Meshes Using Local Topological Transformations
Ghadyani, Hamid; Sullivan, John; Wu, Ziji
2009-01-01
Numerous high-quality, volume mesh-generation systems exist. However, no strategy can address all geometry situations without some element qualities being compromised. Many 3D mesh generation algorithms are based on Delaunay tetrahedralization which frequently fails to preserve the input boundary surface topology. For biomedical applications, this surface preservation can be critical as they usually contain multiple material regions of interest coherently connected. In this paper we present an algorithm as a post-processing method that optimizes local regions of compromised element quality and recovers the original boundary surface facets (triangles) regardless of the original mesh generation strategy. The algorithm carves out a small sub-volume in the vicinity of the missing boundary facet or compromised element, creating a cavity. If the task is to recover a surface boundary facet, a natural exit hole in the cavity will be present. This hole is patched with the missing boundary surface face first followed by other patches to seal the cavity. If the task was to improve a compromised region, then the cavity is already sealed. Every triangular facet of the cavity shell is classified as an active face and can be connected to another shell node creating a tetrahedron. In the process the base of the tetrahedron is removed from the active face list and potentially 3 new active faces are created. This methodology is the underpinnings of our last resort method. Each active face can be viewed as the trunk of a tree. An exhaustive breath and depth search will identify all possible tetrahedral combinations to uniquely fill the cavity. We have streamlined this recursive process reducing the time complexity by orders of magnitude. The original surfaces boundaries (internal and external) are fully restored and the quality of compromised regions improved. PMID:20305743
The cable catapult - Putting it there and keeping it there
NASA Technical Reports Server (NTRS)
Forward, Robert L.; Conley, Buford R.; Stanek, Clay; Ramsey, William
1992-01-01
The cable catapult is the previously proposed method of using long space tethers for high speed interplanetary transport. A long conductive multistrand cable would be connected to a power supply and pointed in the desired direction. A linear motor would pull itself along the powered cable strands and launch a payload capsule toward a distant planet, where it would be caught and decelerated by another cable catapult positioned there. In this paper it is shown how cable catapults can be used to transport themselves to a distant planet and keep themselves in position near the planet despite the tendency of the payload capsule momentum transfer to push them apart.
The cable catapult - Putting it there and keeping it there
NASA Astrophysics Data System (ADS)
Forward, Robert L.; Conley, Buford R.; Stanek, Clay; Ramsey, William
1992-07-01
The cable catapult is the previously proposed method of using long space tethers for high speed interplanetary transport. A long conductive multistrand cable would be connected to a power supply and pointed in the desired direction. A linear motor would pull itself along the powered cable strands and launch a payload capsule toward a distant planet, where it would be caught and decelerated by another cable catapult positioned there. In this paper it is shown how cable catapults can be used to transport themselves to a distant planet and keep themselves in position near the planet despite the tendency of the payload capsule momentum transfer to push them apart.
Irizarry, Daniel; Wadman, Michael C; Bernhagen, Mary A; Miljkovic, Nikola; Boedeker, Ben H
2012-01-01
This work describes the use of Adobe Connect software along with algorithm software to provide the necessary audio visual communication platform for telementoring a complex medical procedure to novice providers located at a distant site.
Relativistic quantum Darwinism in Dirac fermion and graphene systems
NASA Astrophysics Data System (ADS)
Ni, Xuan; Huang, Liang; Lai, Ying-Cheng; Pecora, Louis
2012-02-01
We solve the Dirac equation in two spatial dimensions in the setting of resonant tunneling, where the system consists of two symmetric cavities connected by a finite potential barrier. The shape of the cavities can be chosen to yield both regular and chaotic dynamics in the classical limit. We find that certain pointer states about classical periodic orbits can exist, which are signatures of relativistic quantum Darwinism (RQD). These localized states suppress quantum tunneling, and the effect becomes less severe as the underlying classical dynamics in the cavity is chaotic, leading to regularization of quantum tunneling. Qualitatively similar phenomena have been observed in graphene. A physical theory is developed to explain relativistic quantum Darwinism and its effects based on the spectrum of complex eigenenergies of the non-Hermitian Hamiltonian describing the open cavity system.
Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes
Palmer, R.B.
1991-05-21
An accelerating cavity is disclosed having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps. 17 figures.
Malik, Dharmender; Jois, Abhiram; Singh, Harmandeep; Bora, Girdhar S; Basher, Rajender Kumar; Mittal, Bhagwant Rai
2017-09-01
We report a case of 23-year-old man who presented with complaints of progressive abdominal distension for the past 3 months along with the loss of appetite and weight and had a large solid cystic mass in the left half of the abdominal cavity revealed on ultrasonography and contrast-enhanced CT of the abdomen. Subsequent biopsy and histopathology revealed it to be neuroblastoma. Ga-DOTANOC PET/CT scan performed to rule out distant metastasis showed intense radiotracer uptake distributed throughout the skeleton, mimicking a super scan.
Merkel Cell Carcinoma Metastatic to Pleural Fluid: A Case Report.
Rhee, Ye-Young; Kim, Soo Hee; Kim, Eun Kyung; Kim, Se Hoon
2018-05-01
Merkel cell carcinoma (MCC) is a rare aggressive neuroendocrine carcinoma of the skin that shows locoregional or distant metastasis. Metastasis of MCC to body cavity effusion is extremely rare; only three cases have been reported so far. Metastatic MCC in effusion cytology shows small blue round cells with fine stippled chromatin like other small blue round cell tumors such as small cell lung carcinoma or lymphoma. The diagnosis of metastatic MCC can grant patients good chances at recently advanced therapeutic options. Here, we present a case of metastatic MCC to pleural effusion with characteristic single file-like pattern.
Wang, Che-Chuan; Floyd, Scott R; Chang, Chin-Hong; Warnke, Peter C; Chio, Chung-Ching; Kasper, Ekkehard M; Mahadevan, Anand; Wong, Eric T; Chen, Clark C
2012-02-01
Development of hypofractionated stereotactic radiosurgery (HSRS) has expanded the size of lesion that can be safely treated by focused radiation in a limited number of treatment sessions. However, clinical data regarding the efficacy and morbidity of HSRS in the treatment of cerebral metastasis is lacking. Here, we review our experience with CyberKnife(®) HSRS for this indication. From 2005 to 2010, we identified 37 patients with large (>3 cm in diameter) cerebral metastases resection cavity that was treated with HSRS. This constituted approximately 8% of all treated resection cavities. We reviewed dose regimens, local control, distal control, and treatment associated morbidities. Primary sites for the metastatic lesions included: lung (n = 10), melanoma (n = 12), breast (n = 9), kidney (n = 4), and colon (n = 2). All patients underwent resection of the cerebral metastasis and received 800 cGy × 3 daily fractions to the resection cavity. Of the 37 patients treated, one-year follow-up data was available for 35 patients. The median survival was 5.5 months. Actuarial local control rate at 6 months was 80%. Local failures did not correlate with prior WBRT, or tumor histology. Distant recurrence occurred in 7 of the 35 patients. Morbidities associated with HSRS totaled 9%, including radiation necrosis (n = 1, 2.9%), prolonged steroid use (n = 1, 2.9%), and new-onset seizures (n = 1, 2.9%). This study demonstrates the safety and efficacy of an 800 cGy × 3 daily fractions CyberKnife(®) HSRS regimen for irradiation of large resection cavity. The efficacy compares favorably to historical data derived from patients undergoing WBRT, SRS, or brachytherapy.
Microfluidic chest cavities reveal that transmural pressure controls the rate of lung development.
Nelson, Celeste M; Gleghorn, Jason P; Pang, Mei-Fong; Jaslove, Jacob M; Goodwin, Katharine; Varner, Victor D; Miller, Erin; Radisky, Derek C; Stone, Howard A
2017-12-01
Mechanical forces are increasingly recognized to regulate morphogenesis, but how this is accomplished in the context of the multiple tissue types present within a developing organ remains unclear. Here, we use bioengineered 'microfluidic chest cavities' to precisely control the mechanical environment of the fetal lung. We show that transmural pressure controls airway branching morphogenesis, the frequency of airway smooth muscle contraction, and the rate of developmental maturation of the lungs, as assessed by transcriptional analyses. Time-lapse imaging reveals that branching events are synchronized across distant locations within the lung, and are preceded by long-duration waves of airway smooth muscle contraction. Higher transmural pressure decreases the interval between systemic smooth muscle contractions and increases the rate of morphogenesis of the airway epithelium. These data reveal that the mechanical properties of the microenvironment instruct crosstalk between different tissues to control the development of the embryonic lung. © 2017. Published by The Company of Biologists Ltd.
Oral metastasis from primary transitional cell carcinoma of the renal pelvis: report of a case.
Zhang, Y; Gu, Z-Y; Tian, Z; Yang, C; Cai, X-Y
2010-07-01
Transitional cell carcinoma of the renal pelvis is initially a slow growing tumor arising from the transitional epithelium of the mucous membrane of the renal pelvis. Recurrences occur in two forms: superficial bladder cancer and distant metastases. The common metastasis is in the lung, liver, brain and bone. Oral metastasis is seldom reported. The authors report an unusual case of transitional cell carcinoma of the renal pelvis metastasized to the oral cavity and lung simultaneously in a 74-year-old man, which occurred 1 year after a left nephroureterectomy. The patient underwent six courses of chemotherapy (gemcitabine, oxaliplatin, fluorouracil and nedaplatin), and received radiotherapy for the oral lesion. The symptoms were alleviated, but the tumor recurred in the oral cavity 2 years later. Brain and liver metastases were confirmed by CT. Repeated radiotherapy for oral metastasis was performed, but the patient died 4 years after the initial nephroureterectomy due to multiple metastases. Copyright 2010 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Zhang, Ruiliang; Qu, Yanchen; Zhao, Weijiang; Liu, Chuang; Chen, Zhenlei
2017-06-01
We demonstrate a terahertz-wave parametric oscillator (TPO) with an asymmetrical porro-prism (PP) resonator configuration, consisting of a close PP corner reflector and a distant output mirror relative to the MgO:LiNbO3 crystal. Based on this cavity, frequency tuning of Stokes and the accompanied terahertz (THz) waves is realized just by rotating the plane mirror. Furthermore, THz output with high efficiency and wide tuning range is obtained. Compared with a conventional TPO employing a plane-parallel resonator of the same cavity length and output loss, the low end of the frequency tuning range is extended to 0.96 THz from 1.2 THz. The highest output obtained at 1.28 THz is enhanced by about 25%, and the oscillation threshold pump energy measured at 1.66 THz is reduced by about 4.5%. This resonator configuration also shows some potential to simplify the structure and application for intracavity TPOs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hensen, Matthias; Heilpern, Tal; Gray, Stephen K.
Establishing strong coupling between spatially separated and thus selectively addressable quantum emitters is a key ingredient to complex quantum optical schemes in future technologies. Insofar as many plasmonic nanostructures are concerned, however, the energy transfer and mutual interaction strength between distant quantum emitters can fail to provide strong coupling. Here, based on mode hybridization, the longevity and waveguide character of an elliptical plasmon cavity are combined with intense and highly localized field modes of suitably designed nanoantennas. Based on FDTD simulations a quantum emitter-plasmon coupling strength hg = 16.7 meV is reached while simultaneously keeping a small plasmon resonance linemore » width h gamma(s) = 33 meV. This facilitates strong coupling, and quantum dynamical simulations reveal an oscillatory exchange of excited state population arid a notable degree of entanglement between the quantum emitters spatially separated by 1.8 mu m, i.e., about twice the operating wavelength.« less
Radiotherapy after surgical resection for head and neck mucosal melanoma.
Wu, Abraham J; Gomez, Jennifer; Zhung, Joanne E; Chan, Kelvin; Gomez, Daniel R; Wolden, Suzanne L; Zelefsky, Michael J; Wolchok, Jedd D; Carvajal, Richard D; Chapman, Paul B; Wong, Richard J; Shaha, Ashok R; Kraus, Dennis H; Shah, Jatin P; Lee, Nancy Y
2010-06-01
To present our single-institution experience with postoperative radiotherapy for mucosal melanoma of the head and neck. Between 1992 and 2007, 27 patients with mucosal melanoma of the head and neck underwent surgical resection followed by postoperative radiotherapy. Median age was 68 years (range: 45-89 years). Sites included were sinonasal in 24 patients, oral cavity in 2, and oropharynx in 1. All but 2 patients had stage I disease. Twenty-two patients received hypofractionated radiation. Radiation techniques were intensity-modulated radiation therapy in 13, 3-dimensional conformal in 4, and conventional in 10. The median follow-up for living patients was 45 months (range: 24-122 months). The 3- and 5-year estimates of local progression-free, loco-regional progression-free, distant metastasis-free, and overall survival were: 47% and 35%; 34% and 22%; 30% and 24%; and 40% and 33%, respectively. Median time to local failure and distant metastasis was 32 and 14 months, respectively. Acute toxicities included 19% with grade 2 or higher mucositis. No late complications related to the optic structures were seen. Modern radiotherapeutic techniques including intensity-modulated radiation therapy appear feasible and well-tolerated in the postoperative treatment of head and neck mucosal melanoma. Unusual or serious late complications have not been observed despite extensive use of hypofractionated regimens. However, rates of local and distant failure remain high.
A Novel Fabry-Perot Cavity Fiber Sensor
NASA Astrophysics Data System (ADS)
Lin, Chun; Huang, Yuan Qing; Lei, Wang; Ye, Xiao Juan
Fabry-Perot (F-P) cavity fiber sensors are often used in acceleration, vibration and pressure measurement. When the structure of sensors are similar, there are the same disadvantages exist. A novel design of Fabry-Perot (F-P) cavity fiber sensor is described in this paper, which is composed by a non-coating end-face and a holophote. Triple beams interference is formed in the sensor and shows higher sensitivity. In order to demodulate interference signal in great background noise, two photodiodes are connected in series to form short circuit current which delimits the common mode signal. Experimental results are described for the sensor signal responding to the vibration excited by PZT.^p
NASA Astrophysics Data System (ADS)
Davidovikj, D.; Bouwmeester, D.; van der Zant, H. S. J.; Steeneken, P. G.
2018-07-01
We report on the development of a pneumatically coupled graphene membrane system, comprising of two circular cavities connected by a narrow trench. Both cavities and the trench are covered by a thin few-layer graphene membrane to form a sealed dumbbell-shaped chamber. Local electrodes at the bottom of each cavity allow for actuation of each membrane separately, enabling electrical control and manipulation of the gas flow inside the channel. Using laser interferometry, we measure the displacement of each drum at atmospheric pressure as a function of the frequency of the electrostatic driving force and provide a proof-of-principle of using graphene membranes to pump attolitre quantities of gases at the nanoscale.
Apparatus for testing skin samples or the like
Holland, J.M.
1982-08-31
An apparatus for testing the permeability of living skin samples has a flat base with a plurality of sample-holding cavities formed in its upper surface, the samples being placed in counterbores in the cavities with the epidermis uppermost. O-rings of Teflon washers are respectively placed on the samples and a flat cover is connected to the base to press the rings against the upper surfaces of the samples. Media to maintain tissue viability and recovery of metabolites is introduced into the lower portion of the sample-holding cavities through passages in the base. Test materials are introduced through holes in the cover plate after assembly of the chamber.
Fujimoto, Kayo; Coghill, Lyndon M; Weier, Christopher A; Hwang, Lu-Yu; Kim, Ju Yeong; Schneider, John A; Metzker, Michael L; Brown, Jeremy M
2017-09-01
We explore the phylogenetic relationships among HIV sequences sampled from young adult black men who have sex with men (YAB-MSM), who are connected through peer referral/social ties and who attend common venues. Using 196 viral sequences sampled from the peripheral blood mononuclear cells of 10 individuals, our preliminary phylogenetic results indicate that these socially connected YAB-MSM are infected with distantly related viruses and provide no evidence for viral transmission between network members. Our results suggest that HIV-prevention strategies that target young adult MSM should extend beyond their network members and local community.
Dual Check Valve and Method of Controlling Flow Through the Same
NASA Technical Reports Server (NTRS)
Corallo, Roger (Inventor)
2016-01-01
A dual check valve includes, a housing having a cavity fluidically connecting three ports, a movable member movably engaged within the cavity from at least a first position occluding a first port of the three ports, a second position occluding a second port of the three ports, and a third position allowing flow between both the first port, the second port and a third port of the three ports.
Cognitive Profile in Low, Medium and High Creative Students
ERIC Educational Resources Information Center
Ferrando, Mercedes; Bermejo, Rosario; Sainz, Marta; Ferrandiz, Carmen; Prieto, Maria Dolores; Soto, Gloria
2012-01-01
Introduction: The aim of the present work is to advance in the study of creativity-intelligence relationship looking into the students' cognitive profiles. It is hypothesized that, if creative ideas emerge as result of connecting distant concepts, and a balanced cognitive profile (without significant differences between ability levels) can…
Design and Analysis of a Forging Die for Manufacturing of Multiple Connecting Rods
NASA Astrophysics Data System (ADS)
Megharaj, C. E.; Nagaraj, P. M.; Jeelan Pasha, K.
2016-09-01
This paper demonstrates to utilize the hammer capacity by modifying the die design such that forging hammer can manufacture more than one connecting rod in a given forging cycle time. To modify the die design study is carried out to understand the parameters that are required for forging die design. By considering these parameters, forging die is designed using design modelling tool solid edge. This new design now can produce two connecting rods in same capacity hammer. The new design is required to validate by verifying complete filing of metal in die cavities without any defects in it. To verify this, analysis tool DEFORM 3D is used in this project. Before start of validation process it is require to convert 3D generated models in to. STL file format to import the models into the analysis tool DEFORM 3D. After importing these designs they are analysed for material flow into the cavities and energy required to produce two connecting rods in new forging die design. It is found that the forging die design is proper without any defects and also energy graph shows that the forging energy required to produce two connecting rods is within the limit of that hammer capacity. Implementation of this project increases the production of connecting rods by 200% in less than previous cycle time.
Green, Adam E; Kraemer, David J M; Fugelsang, Jonathan A; Gray, Jeremy R; Dunbar, Kevin N
2010-01-01
Solving problems often requires seeing new connections between concepts or events that seemed unrelated at first. Innovative solutions of this kind depend on analogical reasoning, a relational reasoning process that involves mapping similarities between concepts. Brain-based evidence has implicated the frontal pole of the brain as important for analogical mapping. Separately, cognitive research has identified semantic distance as a key characteristic of the kind of analogical mapping that can support innovation (i.e., identifying similarities across greater semantic distance reveals connections that support more innovative solutions and models). However, the neural substrates of semantically distant analogical mapping are not well understood. Here, we used functional magnetic resonance imaging (fMRI) to measure brain activity during an analogical reasoning task, in which we parametrically varied the semantic distance between the items in the analogies. Semantic distance was derived quantitatively from latent semantic analysis. Across 23 participants, activity in an a priori region of interest (ROI) in left frontopolar cortex covaried parametrically with increasing semantic distance, even after removing effects of task difficulty. This ROI was centered on a functional peak that we previously associated with analogical mapping. To our knowledge, these data represent a first empirical characterization of how the brain mediates semantically distant analogical mapping.
Abnormal brain synchrony in Down Syndrome☆
Anderson, Jeffrey S.; Nielsen, Jared A.; Ferguson, Michael A.; Burback, Melissa C.; Cox, Elizabeth T.; Dai, Li; Gerig, Guido; Edgin, Jamie O.; Korenberg, Julie R.
2013-01-01
Down Syndrome is the most common genetic cause for intellectual disability, yet the pathophysiology of cognitive impairment in Down Syndrome is unknown. We compared fMRI scans of 15 individuals with Down Syndrome to 14 typically developing control subjects while they viewed 50 min of cartoon video clips. There was widespread increased synchrony between brain regions, with only a small subset of strong, distant connections showing underconnectivity in Down Syndrome. Brain regions showing negative correlations were less anticorrelated and were among the most strongly affected connections in the brain. Increased correlation was observed between all of the distributed brain networks studied, with the strongest internetwork correlation in subjects with the lowest performance IQ. A functional parcellation of the brain showed simplified network structure in Down Syndrome organized by local connectivity. Despite increased interregional synchrony, intersubject correlation to the cartoon stimuli was lower in Down Syndrome, indicating that increased synchrony had a temporal pattern that was not in response to environmental stimuli, but idiosyncratic to each Down Syndrome subject. Short-range, increased synchrony was not observed in a comparison sample of 447 autism vs. 517 control subjects from the Autism Brain Imaging Exchange (ABIDE) collection of resting state fMRI data, and increased internetwork synchrony was only observed between the default mode and attentional networks in autism. These findings suggest immature development of connectivity in Down Syndrome with impaired ability to integrate information from distant brain regions into coherent distributed networks. PMID:24179822
Static latching arrangement and method
Morrison, Larry
1988-01-01
A latching assembly for use in latching a cable to and unlatching it from a given object in order to move an object from one location to another is disclosed herein. This assembly includes a weighted sphere mounted to one end of a cable so as to rotate about a specific diameter of the sphere. The assembly also includes a static latch adapted for connection with the object to be moved. This latch includes an internal latching cavity for containing the sphere in a latching condition and a series of surfaces and openings which cooperate with the sphere in order to move the sphere into and out of the latching cavity and thereby connect the cable to and disconnect it from the latch without using any moving parts on the latch itself.
Outcome Analysis of Patients With Oral Cavity Cancer and Extracapsular Spread in Neck Lymph Nodes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liao, Chun-Ta, E-mail: liaoct@adm.cgmh.org.tw; Department of Head and Neck Oncology Group, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan; Lee, Li-Yu
Purpose: Extracapsular spread (ECS) in neck lymph nodes is a major adverse prognostic factor in patients with oral cavity squamous cell carcinoma (OSCC). We conducted a retrospective analysis of prognostic factors in this patient group and tried to identify a subset of patients with a worse prognosis suitable for more aggressive therapeutic interventions. Methods and Materials: Enrolled in the study were 255 OSCC patients with ECS in neck nodes and without evidence of distant metastasis. All participants were followed-up for at least 2 years or censored at last follow-up. The 5-year rates of control, distant metastasis, and survival were themore » main outcome measures. Results: Level IV/V lymph node metastases and tumor depth {>=}12 mm were independent predictors of 5-year survival and identified three prognostic groups. In the low-risk group (no level IV/V metastases and tumor depth <12 mm), the 5-year disease-free, disease-specific, and overall survival rates were 60%, 66%, and 50%, respectively. In the intermediate-risk group (no level IV/V metastases and tumor depth {>=}12 mm), the 5-year disease-free, disease-specific, and overall survival rates were 39%, 41%, and 28%, respectively. In the high-risk group (evidence of level IV/V metastases), the 5-year disease-free, disease-specific, and overall survival rates were 14%, 12%, and 10%, respectively. Conclusions: Among OSCC patients with ECS, those with level IV/V metastases appear to have the worst prognosis followed by without level IV/V metastases and tumor depth {>=}12 mm. An aggressive therapeutic approach may be suitable for intermediate- and high-risk patients.« less
Patel, Kirtesh R; Prabhu, Roshan S; Kandula, Shravan; Oliver, Daniel E; Kim, Sungjin; Hadjipanayis, Constantinos; Olson, Jeffery J; Oyesiku, Nelson; Curran, Walter J; Khan, Mohammad K; Shu, Hui-Kuo; Crocker, Ian
2014-12-01
The aim of this study was to compare outcomes of postoperative whole brain radiation therapy (WBRT) to stereotactic radiosurgery (SRS) alone in patients with resected brain metastases (BM). We reviewed records of patients who underwent surgical resection of BM followed by WBRT or SRS alone between 2003 and 2013. Local control (LC) of the treated resected cavity, distant brain control (DBC), leptomeningeal disease (LMD), overall survival (OS), and radiographic leukoencephalopathy rates were estimated by the Kaplan-Meier method. One-hundred thirty-two patients underwent surgical resection for 141 intracranial metastases: 36 (27 %) patients received adjuvant WBRT and 96 (73 %) received SRS alone to the resection cavity. One-year OS (56 vs. 55 %, p = 0.64) and LC (83 vs. 74 %, p = 0.31) were similar between patients receiving WBRT and SRS. After controlling for number of BM, WBRT was associated with higher 1-year DBC compared with SRS (70 vs. 48 %, p = 0.03); single metastasis and WBRT were the only significant predictors for reduced distant brain recurrence in multi-variate analysis. Freedom from LMD was higher with WBRT at 18 months (87 vs. 69 %, p = 0.045), while incidence of radiographic leukoencephalopathy was higher with WBRT at 12 months (47 vs. 7 %, p = 0.001). One-year freedom from WBRT in the SRS alone group was 86 %. Compared with WBRT for patients with resected BM, SRS alone demonstrated similar LC, higher rates of LMD and inferior DBC, after controlling for the number of BM. However, OS was similar between groups. The results of ongoing clinical trials are needed to confirm these findings.
Amit, Moran; Yen, Tzu-Chen; Liao, Chun-Ta; Chaturvedi, Pankaj; Agarwal, Jai Prakash; Kowalski, Luiz P; Ebrahimi, Ardalan; Clark, Jonathan R; Kreppel, Matthias; Zöller, Joachim; Fridman, Eran; Bolzoni, Villaret A; Shah, Jatin P; Binenbaum, Yoav; Patel, Snehal G; Gil, Ziv
2013-12-15
An association between the survival of patients with oral cavity squamous cell carcinoma (OCSCC) and advancements in diagnosis and therapy has not been established. This was a retrospective, longitudinal, international, population-based study of 2738 patients who underwent resection of OCSCC during 2 different decades. Characteristics of patients from 7 international cancer centers who received treatment between 1990 and 2000 (group A; n = 735) were compared with patients who received treatment between 2001 and 2011 (group B; n = 2003). Patients in group B had more advanced tumors and tended to develop distant metastases more frequently than patients in group A (P = .005). More group B patients underwent selective neck dissection and received adjuvant radiotherapy (P < .001). Outcome analysis revealed a significant improvement in 5-year overall survival, from 59% for group A to 70% for group B (P < .001). There was also a significant improvement in disease-specific survival associated with operations performed before and after 2000 (from 69% to 81%, respectively; P < .001). Surgery after 2000, negative margins, adjuvant treatment, and early stage disease were independent predictors of a better outcome in multivariate analysis. The decade of treatment was an independent prognostic factor for cancer-specific mortality (hazard ratio, 0.42; 95% confidence interval, 0.3-0.6). The survival rate of patients with OCSCC improved significantly during the past 2 decades despite older age, more advanced disease stage, and a higher rate of distant metastases. The current results suggest that the prognosis for patients with OCSCC has improved over time, presumably because of advances in imaging and therapy. © 2013 American Cancer Society.
NASA Astrophysics Data System (ADS)
Perreard, S.; Wildner, E.
1994-12-01
Many processes are controlled by experts using some kind of mental model to decide on actions and make conclusions. This model, based on heuristic knowledge, can often be represented by rules and does not have to be particularly accurate. Such is the case for the problem of conditioning high voltage RF cavities; the expert has to decide, by observing some criteria, whether to increase or to decrease the voltage and by how much. A program has been implemented which can be applied to a class of similar problems. The kernel of the program is a small rule base, which is independent of the kind of cavity. To model a specific cavity, we use fuzzy logic which is implemented as a separate routine called by the rule base, to translate from numeric to symbolic information.
NASA Astrophysics Data System (ADS)
Artemenko, S. N.; Samoylenko, G. M.
2016-11-01
We study the processes of radiation output from a microwave storage cavity through a superconducting interference switch, which is based on a H-junction with a superconducting switching cavity connected to the side branch of the junction for various ways of controlling the parameters of the switching cavity. It is shown that efficient control over radiation output in such a switch can be achieved by varying the resonance frequency or Q-factor of the switching cavity, as well as by varying these parameters simultaneously. It is found that in the case of controlling the resonance frequency of the switching cavity, there exists an optimal interval of the frequency variation, within which the total efficiency and extraction efficiency are maximum. When the Q-factor of the switching cavity changes, the dependence of the total efficiency and extraction efficiency on the Q-factor has the monotonic character. The mixed regime of radiation output control is also studied. The envelopes of the output compressor pulses are plotted on the basis of recurrent relationships between the amplitudes of the waves in the system for three regimes of switch operation. It is shown that pulses with an almost rectangular shape of the envelope can be formed in the regime of controlling the switching cavity by varying the Q-factor. An example of possible realization of the switching cavity is considered.
Integrated Cavity QED in a linear Ion Trap Chip for Enhanced Light Collection
NASA Astrophysics Data System (ADS)
Benito, Francisco; Jonathan, Sterk; Boyan, Tabakov; Haltli, Raymond; Tigges, Chris; Stick, Daniel; Balin, Matthew; Moehring, David
2012-06-01
Realizing a scalable trapped-ion quantum information processor may require integration of tools to manipulate qubits into trapping devices. We present efforts towards integrating a 1 mm optical cavity into a microfabricated surface ion trap to efficiently connect nodes in a quantum network. The cavity is formed by a concave mirror and a flat coated silicon mirror around a linear trap where ytterbium ions can be shuttled in and out of the cavity mode. By utilizing the Purcell effect to increase the rate of spontaneous emission into the cavity mode, we expect to collect up to 13% of the emitted photons. This work was supported by Sandia's Laboratory Directed Research and Development (LDRD) and the Intelligence Advanced Research Projects Activity (IARPA). Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
McIntyre, Timothy J.
1994-01-01
A system and method for generating a desired displacement of an object, i.e., a target, from a reference position with ultra-high accuracy utilizes a Fabry-Perot etalon having an expandable tube cavity for resolving, with an Iodine stabilized laser, displacements with high accuracy and for effecting (as an actuator) displacements of the target. A mechanical amplifier in the form of a micropositioning stage has a platform and a frame which are movable relative to one another, and the tube cavity of the etalon is connected between the platform and frame so that an adjustment in length of the cavity effects a corresponding, amplified movement of the frame relative to the cavity. Therefore, in order to provide a preselected magnitude of displacement of the stage frame relative to the platform, the etalon tube cavity is adjusted in length by a corresponding amount. The system and method are particularly well-suited for use when calibrating a high accuracy measuring device.
Hot interstellar tunnels. 1: Simulation of interacting supernova remnants
NASA Technical Reports Server (NTRS)
Smith, B. W.
1976-01-01
The theory required to build a numerical simulation of interacting supernova remnants is developed. The hot cavities within a population of remnants will become connected, with varying ease and speed, for a variety of assumed conditions in the outer shells of old remnants. Apparently neither radiative cooling nor thermal conduction in a large-scale galactic magnetic field can destroy hot cavity regions, if they grow, faster than they are reheated by supernova shock waves, but interstellar mass motions disrupt the contiguity of extensive cavities necessary for the dispersal of these shocks over a wide volume. Monte Carlo simulations show that a quasi-equilibrium is reached in the test space within 10 million yrs of the first supernova and is characterized by an average cavity filling fraction of the interstellar volume. Aspects of this equilibrium are discussed for a range of supernova rates. Two predictions are not confirmed within this range: critical growth of hot regions to encompass the entire medium, and the efficient quenching of a remnant's expansion by interaction with other cavities.
Samstein, Robert M; Carvajal, Richard D; Postow, Michael A; Callahan, Margaret K; Shoushtari, Alexander N; Patel, Snehal G; Lee, Nancy Y; Barker, Christopher A
2016-09-01
Sinonasal mucosal melanoma is a rare neoplasm with a poor prognosis. Retrospective analysis was conducted on 78 patients with localized sinonasal mucosal melanoma treated at Memorial Sloan Kettering Cancer Center (MSKCC from 1998-2013). Demographic, tumor, imaging, and treatment factors were recorded and survival and disease-control outcomes were analyzed. Median overall survival (OS) and disease-specific survival (DSS) were 32 and 50 months, respectively. Median locoregional recurrence-free survival (LRFS) and distant recurrence-free survival (DRFS) were 43 and 12 months, respectively. Multivariate analysis demonstrated greater OS in nasal cavity tumors and earlier T classification. Radiotherapy (RT) was associated with significantly greater LRFS (5-years; 35% vs 59%; p = .01), but no difference in OS. Post-RT positron emission tomography (PET) response was associated with greater OS. Distant metastasis is the predominant mode of recurrence in sinonasal mucosal melanoma, but local recurrence remains common. RT is associated with improved local control, but no survival benefit. The prognostic value of post-RT PET imaging warrants further investigation. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1310-1317, 2016. © 2016 Wiley Periodicals, Inc.
Dielectric supported radio-frequency cavities
Yu, David U. L.; Lee, Terry G.
2000-01-01
A device which improves the electrical and thermomechanical performance of an RF cavity, for example, in a disk-loaded accelerating structure. A washer made of polycrystalline diamond is brazed in the middle to a copper disk washer and at the outer edge to the plane wave transformer tank wall, thus dissipating heat from the copper disk to the outer tank wall while at the same time providing strong mechanical support to the metal disk. The washer structure eliminates the longitudinal connecting rods and cooling channels used in the currently available cavities, and as a result minimizes problems such as shunt impedance degradation and field distortion in the plane wave transformer, and mechanical deflection and uneven cooling of the disk assembly.
Using Online Surveys to Engage a School Community
ERIC Educational Resources Information Center
Ayers, Steven
2012-01-01
In the not-too-distant past, using surveys to gauge public opinion was a costly and time-consuming activity that districts generally had to outsource. Today, with the advent of online survey tools such as Survey Monkey and Zoomerang and an increasingly Internet-connected society, surveys have become a useful and accessible tool for school…
Using Compressed Video To Coach/Mentor Distant Teacher Interns.
ERIC Educational Resources Information Center
Hakes, Barbara; And Others
Wyoming, a rural state with a small population scattered over vast geographic areas, brought a compressed digital video network online to connect the University of Wyoming and the State's seven community colleges. The College of Education at the University received a grant to develop a coaching/mentoring model for teacher interns over distance.…
ERIC Educational Resources Information Center
Weinberger, A.; Clark, D. B.; Haekkinen, P.; Tamura, Y.; Fischer, F.
2007-01-01
In recent years, information and communication technology has established new opportunities to participate in online learning environments around the globe. These opportunities include the dissemination of specific online learning environments as well as opportunities for learners to connect to online learning environments in distant locations.…
Extensive cortical rewiring after brain injury.
Dancause, Numa; Barbay, Scott; Frost, Shawn B; Plautz, Erik J; Chen, Daofen; Zoubina, Elena V; Stowe, Ann M; Nudo, Randolph J
2005-11-02
Previously, we showed that the ventral premotor cortex (PMv) underwent neurophysiological remodeling after injury to the primary motor cortex (M1). In the present study, we examined cortical connections of PMv after such lesions. The neuroanatomical tract tracer biotinylated dextran amine was injected into the PMv hand area at least 5 months after ischemic injury to the M1 hand area. Comparison of labeling patterns between experimental and control animals demonstrated extensive proliferation of novel PMv terminal fields and the appearance of retrogradely labeled cell bodies within area 1/2 of the primary somatosensory cortex after M1 injury. Furthermore, evidence was found for alterations in the trajectory of PMv intracortical axons near the site of the lesion. The results suggest that M1 injury results in axonal sprouting near the ischemic injury and the establishment of novel connections within a distant target. These results support the hypothesis that, after a cortical injury, such as occurs after stroke, cortical areas distant from the injury undergo major neuroanatomical reorganization. Our results reveal an extraordinary anatomical rewiring capacity in the adult CNS after injury that may potentially play a role in recovery.
NASA Astrophysics Data System (ADS)
Mason, J. M.; Fahy, F. J.
1986-10-01
The effectiveness of tuned Helmholtz resonators connected to the partition cavity in double-leaf partitions utilized in situations requiring low weight structures with high transmission loss is investigated as a method of improving sound transmission loss. This is demonstrated by a simple theoretical model and then experimentally verified. Results show that substantial improvements may be obtained at and around the mass-air-mass frequency for a total resonator volume 15 percent of the cavity volume.
Apparatus for Leak Testing Pressurized Hoses
NASA Technical Reports Server (NTRS)
Underwood, Steve D. (Inventor); Garrison, Steve G. (Inventor); Gant, Bobby D. (Inventor); Palmer, John R. (Inventor)
2015-01-01
A hose-attaching apparatus for leak-testing a pressurized hose may include a hose-attaching member. A bore may extend through the hose-attaching member. An internal annular cavity may extend coaxially around the bore. At least one of a detector probe hole and a detector probe may be connected to the internal annular cavity. At least a portion of the bore may have a diameter which is at least one of substantially equal to and less than a diameter of a hose to be leak-tested.
Storage and retrieval of quantum information with a hybrid optomechanics-spin system
NASA Astrophysics Data System (ADS)
Feng, Zhi-Bo; Zhang, Jian-Qi; Yang, Wan-Li; Feng, Mang
2016-08-01
We explore an efficient scheme for transferring the quantum state between an optomechanical cavity and an electron spin of diamond nitrogen-vacancy center. Assisted by a mechanical resonator, quantum information can be controllably stored (retrieved) into (from) the electron spin by adjusting the external field-induced detuning or coupling. Our scheme connects effectively the cavity photon and the electron spin and transfers quantum states between two regimes with large frequency difference. The experimental feasibility of our protocol is justified with accessible laboratory parameters.
Micro-sonicator for spore lysis
Miles, Robin R.; Belgrader, Phillip; Nasarabadi, Shanavaz L.
2000-01-01
A micro-sonicator for spore lysis. Using micromachining technology, the micro-sonicator uses ultrasonic excitation of spores to perform spore and cell lysis. The micro-sonicator comprises a container with a cavity therein for retaining the sample in an ultrasonic transmission medium, the cavity being closed by a silicon membrane to which an electrode and piezoelectric material are attached, with the electrode and piezoelectric material being electrically connected to an AC signal generator which causes the membrane to flex and vibrate at the frequency of the applied voltage.
Near wall cooling for a highly tapered turbine blade
Liang, George [Palm City, FL
2011-03-08
A turbine blade having a pressure sidewall and a suction sidewall connected at chordally spaced leading and trailing edges to define a cooling cavity. Pressure and suction side inner walls extend radially within the cooling cavity and define pressure and suction side near wall chambers. A plurality of mid-chord channels extend radially from a radially intermediate location on the blade to a tip passage at the blade tip for connecting the pressure side and suction side near wall chambers in fluid communication with the tip passage. In addition, radially extending leading edge and trailing edge flow channels are located adjacent to the leading and trailing edges, respectively, and cooling fluid flows in a triple-pass serpentine path as it flows through the leading edge flow channel, the near wall chambers and the trailing edge flow channel.
Evaluation of mast cell counts and microvessel density in reactive lesions of the oral cavity.
Kouhsoltani, Maryam; Moradzadeh Khiavi, Monir; Tahamtan, Shabnam
2016-01-01
Background. Reliable immunohistochemical assays to assess the definitive role of mast cells (MCs) and angiogenesis in the pathogenesis of oral reactive lesions are generally not available. The aim of the present study was to evaluate mast cell counts (MCC) and microvessel density (MVD) in oral reactive lesions and determine the correlation between MCC and MVD. Methods. Seventy-five cases of reactive lesions of the oral cavity, including pyogenic granuloma, fibroma, peripheral giant cell granuloma, inflammatory fibrous hyperplasia, peripheral ossifying fibroma (15 for each category) were immunohisto-chemically stained with MC tryptase and CD31. Fifteen cases of normal gingival tissue were considered as the control group. The mean MCC and MVD in superficial and deep connective tissues were assessed and total MCC and MVD was computed for each lesion. Results . Statistically significant differences were observed in MCC and MVD between the study groups (P < 0.001). MC tryptase and CD31 expression increased in the superficial connective tissue of each lesion in comparison to the deep con-nective tissue. A significant negative correlation was not found between MCC and MVD in oral reactive lesions (P < 0.001, r = -0.458). Conclusion. Although MCs were present in the reactive lesions of the oral cavity, a direct correlation between MCC and MVD was not found in these lesions. Therefore, a significant interaction between MCs and endothelial cells and an active role for MCs in the growth of oral reactive lesions was not found in this study.
Locality preserving non-negative basis learning with graph embedding.
Ghanbari, Yasser; Herrington, John; Gur, Ruben C; Schultz, Robert T; Verma, Ragini
2013-01-01
The high dimensionality of connectivity networks necessitates the development of methods identifying the connectivity building blocks that not only characterize the patterns of brain pathology but also reveal representative population patterns. In this paper, we present a non-negative component analysis framework for learning localized and sparse sub-network patterns of connectivity matrices by decomposing them into two sets of discriminative and reconstructive bases. In order to obtain components that are designed towards extracting population differences, we exploit the geometry of the population by using a graphtheoretical scheme that imposes locality-preserving properties as well as maintaining the underlying distance between distant nodes in the original and the projected space. The effectiveness of the proposed framework is demonstrated by applying it to two clinical studies using connectivity matrices derived from DTI to study a population of subjects with ASD, as well as a developmental study of structural brain connectivity that extracts gender differences.
Piston pump and method of reducing vapor lock
Phillips, Benjamin A.; Harvey, Michael N.
2000-02-15
A pump includes a housing defining a cavity, at least one bore, a bore inlet, and a bore outlet. The bore extends from the cavity to the outlet and the inlet communicates with the bore at a position between the cavity and the outlet. A crankshaft is mounted in supports and has an eccentric portion disposed in the cavity. The eccentric portion is coupled to a piston so that rotation of the crankshaft reciprocates the piston in the bore between a discharge position an intake position. The bore may be offset from an axis of rotation to reduce bending of the piston during crankshaft rotation. During assembly of the pump, separate parts of the housing can be connected together to facilitate installation of internal pumping components. Also disclosed is a method of reducing vapor lock by mixing vapor and liquid portions of a substance and introducing the mixture into a piston bore.
Piston pump and method of reducing vapor lock
Phillips, Benjamin A.; Harvey, Michael N.
2001-01-30
A pump includes a housing defining a cavity, at least one bore, a bore inlet, and a bore outlet. The bore extends from the cavity to the outlet and the inlet communicates with the bore at a position between the cavity and the outlet. A crankshaft is mounted in supports and has an eccentric portion disposed in the cavity. The eccentric portion is coupled to a piston so that rotation of the crankshaft reciprocates the piston in the bore between a discharge position an intake position. The bore may be offset from an axis of rotation to reduce bending of the piston during crankshaft rotation. During assembly of the pump, separate parts of the housing can be connected together to facilitate installation of internal pumping components. Also disclosed is a method of reducing vapor lock by mixing vapor and liquid portions of a substance and introducing the mixture into a piston bore.
Suppression of Higher Order Modes in an Array of Cavities Using Waveguides
NASA Astrophysics Data System (ADS)
Shashkov, Ya. V.; Sobenin, N. P.; Bazyl, D. S.; Kaminskiy, V. I.; Mitrofanov, A. A.; Zobov, M. M.
An application of additional harmonic cavities operating at multiplies of the main RF system frequency of 400 MHz is currently under discussionin the framework of the High Luminosity LHC upgrade program [1,2]. A structure consisting of two 800 MHz single cell superconducting cavities with grooved beam pipes coupled by drift tubes has been suggested for implementation. However, it is desirable to increase the number of single cells installed in one cryomodule in order to decrease the number of transitions between "warm" and "cold" parts of the collider vacuum chamber. Unfortunately, it can lead to the appearance of higher order modes (HOM) trapped between the cavities. In order to solve this problem the methods of HOM damping with rectangular waveguides connected to the drift tubes were investigated and compared. We describe the results obtained for arrays of 2, 4 and 8 cavitiesin this paper.
Side-branch resonators modelling with Green's function methods
NASA Astrophysics Data System (ADS)
Perrey-Debain, E.; Maréchal, R.; Ville, J. M.
2014-09-01
This paper deals with strategies for computing efficiently the propagation of sound waves in ducts containing passive components. In many cases of practical interest, these components are acoustic cavities which are connected to the duct. Though standard Finite Element software could be used for the numerical prediction of sound transmission through such a system, the method is known to be extremely demanding, both in terms of data preparation and computation, especially in the mid-frequency range. To alleviate this, a numerical technique that exploits the benefit of the FEM and the BEM approach has been devised. First, a set of eigenmodes is computed in the cavity to produce a numerical impedance matrix connecting the pressure and the acoustic velocity on the duct wall interface. Then an integral representation for the acoustic pressure in the main duct is used. By choosing an appropriate Green's function for the duct, the integration procedure is limited to the duct-cavity interface only. This allows an accurate computation of the scattering matrix of such an acoustic system with a numerical complexity that grows very mildly with the frequency. Typical applications involving Helmholtz and Herschel-Quincke resonators are presented.
Steady Flow Generated by a Core Oscillating in a Rotating Spherical Cavity
NASA Astrophysics Data System (ADS)
Kozlov, V. G.; Subbotin, S. V.
2018-01-01
Steady flow generated by oscillations of an inner solid core in a fluid-filled rotating spherical cavity is experimentally studied. The core with density less than the fluid density is located near the center of the cavity and is acted upon by a centrifugal force. The gravity field directed perpendicular to the rotation axis leads to a stationary displacement of the core from the rotation axis. As a result, in the frame of reference attached to the cavity, the core performs circular oscillation with frequency equal to the rotation frequency, and its center moves along a circular trajectory in the equatorial plane around the center of the cavity. For the differential rotation of the core to be absent, one of the poles of the core is connected to the nearest pole of the cavity with a torsionally elastic, flexible fishing line. It is found that the oscillation of the core generates axisymmetric azimuthal fluid flow in the cavity which has the form of nested liquid columns rotating with different angular velocities. Comparison with the case of a free oscillating core which performs mean differential rotation suggests the existence of two mechanisms of flow generation (due to the differential rotation of the core in the Ekman layer and due to the oscillation of the core in the oscillating boundary layers).
Ultrasensitive Electrometry with a Cavity-Embedded Cooper Pair Transistor
NASA Astrophysics Data System (ADS)
Rimberg, A. J.; Li, Juliang
In this experiment a cavity-embedded Cooper-pair transistor (cCPT) is used as a potentially quantum-limited electrometer. The cCPT consists of a Cooper pair transistor placed at the voltage antinode of a 5.7 GHz shorted quarter-wave resonator so that the CPT provides a galvanic connection between the cavity's central conductor and ground plane. The quantum inductance of the CPT, which appears in parallel with the effective inductance of the cavity resonance, can be modulated by application of either a gate voltage to the CPT island or a flux bias to the CPT/cavity loop. Changes in the CPT inductance shift the cavity resonant frequency, and therefore the phase of a microwave signal reflected from the cavity. The reflected wave is amplified by both SLUG and HEMT amplifiers before its phase is measured. The cCPT can also be operated as a Josephson parametric amplifier (JPA). A pump tone at 11.4 GHz sent into the flux bias line has been shown to provide about 10dB gain. The possibility of parametrically amplifying the side bands produced by a charge detection measurement, thereby increasing the overall sensitivity of the cCPT, will also be investigated. Supported by Grants ARO W911NF-13-10377 and NSF DMR 1507400.
A Theoretical Investigation of the Input Characteristics of a Rectangular Cavity-Backed Slot Antenna
NASA Technical Reports Server (NTRS)
Cockrell, C. R.
1975-01-01
Equations which represent the magnetic and electric stored energies are derived for an infinite section of rectangular waveguide and a rectangular cavity. These representations which are referred to as being physically observable are obtained by considering the difference in the volume integrals appearing in the complex Poynting theorem. It is shown that the physically observable stored energies are determined by the field components that vanish in a reference plane outside the aperture. These physically observable representations are used to compute the input admittance of a rectangular cavity-backed slot antenna in which a single propagating wave is assumed to exist in the cavity. The slot is excited by a voltage source connected across its center; a sinusoidal distribution is assumed in the slot. Input-admittance calculations are compared with measured data. In addition, input-admittance curves as a function of electrical slot length are presented for several size cavities. For the rectangular cavity backed slot antenna, the quality factor and relative bandwidth were computed independently by using these energy relationships. It is shown that the asymptotic relationship which is usually assumed to exist between the quality bandwidth and the reciprocal of relative bandwidth is equally valid for the rectangular cavity backed slot antenna.
[The development of a distribution system for medical lasers and its clinical application].
Okae, S; Ishiguchi, T; Ishigaki, T; Sakuma, S
1991-02-25
We developed a new laser beam generator system which can deliver laser beam to multiple terminals in distant clinical therapy rooms. The system possesses the distribution equipment by which Nd-YAG laser power is distributed to 8 output terminals under the computer control. Distributed laser beam is delivered to each distant terminal with clinical informations through the optical fiber. In the fundamental studies, possibility of distant transportation of laser beam (30 m) only with 10% loss of energy and without dangerous heating at the connection parts was shown. There seems to be no disadvantage associated with distribution laser beam. In the clinical study, the system was applied to five patients with the symptoms including hemosputum, esophageal stenosis, hemorrhage, lip ulcer and pain. Clinical usefulness of the system was proved. The advantages of the system are as follows: 1. Benefit of cost reduction due to multiple use of single laser source. 2. No necessity of transport of the equipment. 3. No requirement of a wide space to install the equipment in the distant room. 4. Efficient management and maintenance of the system by centralization. Further improvements, e.g., simultaneous use at multiple terminals and elongation of transportation up to 340 m, make the system more useful for clinical application.
Axion searches with microwave filters: the RADES project
NASA Astrophysics Data System (ADS)
Álvarez Melcón, Alejandro; Arguedas Cuendis, Sergio; Cogollos, Cristian; Díaz-Morcillo, Alejandro; Döbrich, Babette; Gallego, Juan Daniel; Gimeno, Benito; Irastorza, Igor G.; José Lozano-Guerrero, Antonio; Malbrunot, Chloé; Navarro, Pablo; Peña Garay, Carlos; Redondo, Javier; Vafeiadis, Theodoros; Wuensch, Walter
2018-05-01
We propose, design and construct a variant of the conventional axion haloscope concept that could be competitive in the search for dark matter axions of masses in the decade 10–100 μeV. Theses masses are located somewhat above the mass range in which existing experiments have reached sensitivity to benchmark QCD axion models. Our haloscope consists of an array of small microwave cavities connected by rectangular irises, in an arrangement commonly used in radio-frequency filters. The size of the unit cavity determines the main resonant frequency, while the possibility to connect a large number of cavities allows to reach large detection volumes. We develop the theoretical framework of the detection concept, and present design prescriptions to optimize detection capabilities. We describe the design and realization of a first small-scale prototype of this concept, called Relic Axion Detector Exploratory Setup (RADES). It consists of a copper-coated stainless steel five-cavities microwave filter with the detecting mode operating at around 8.4 GHz. This structure has been electromagnetically characterized at 2 K and 298 K, and it is now placed in ultra-high vacuum in one of the twin-bores of the 9 T CAST dipole magnet at CERN. We describe the data acquisition system developed for relic axion detection, and present preliminary results of the electromagnetic properties of the microwave filter, which show the potential of filters to reach QCD axion window sensitivity at X-band frequencies.
Turbine engine component with cooling passages
Arrell, Douglas J [Oviedo, FL; James, Allister W [Orlando, FL
2012-01-17
A component for use in a turbine engine including a first member and a second member associated with the first member. The second member includes a plurality of connecting elements extending therefrom. The connecting elements include securing portions at ends thereof that are received in corresponding cavities formed in the first member to attach the second member to the first member. The connecting elements are constructed to space apart a first surface of the second member from a first surface of the first member such that at least one cooling passage is formed between adjacent connecting elements and the first surface of the second member and the first surface of the first member.
Measuring Brain Connectivity: Diffusion Tensor Imaging Validates Resting State Temporal Correlations
Skudlarski, Pawel; Jagannathan, Kanchana; Calhoun, Vince D.; Hampson, Michelle; Skudlarska, Beata A.; Pearlson, Godfrey
2015-01-01
Diffusion tensor imaging (DTI) and resting state temporal correlations (RSTC) are two leading techniques for investigating the connectivity of the human brain. They have been widely used to investigate the strength of anatomical and functional connections between distant brain regions in healthy subjects, and in clinical populations. Though they are both based on magnetic resonance imaging (MRI) they have not yet been compared directly. In this work both techniques were employed to create global connectivity matrices covering the whole brain gray matter. This allowed for direct comparisons between functional connectivity measured by RSTC with anatomical connectivity quantified using DTI tractography. We found that connectivity matrices obtained using both techniques showed significant agreement. Connectivity maps created for a priori defined anatomical regions showed significant correlation, and furthermore agreement was especially high in regions showing strong overall connectivity, such as those belonging to the default mode network. Direct comparison between functional RSTC and anatomical DTI connectivity, presented here for the first time, links two powerful approaches for investigating brain connectivity and shows their strong agreement. It provides a crucial multi-modal validation for resting state correlations as representing neuronal connectivity. The combination of both techniques presented here allows for further combining them to provide richer representation of brain connectivity both in the healthy brain and in clinical conditions. PMID:18771736
Skudlarski, Pawel; Jagannathan, Kanchana; Calhoun, Vince D; Hampson, Michelle; Skudlarska, Beata A; Pearlson, Godfrey
2008-11-15
Diffusion tensor imaging (DTI) and resting state temporal correlations (RSTC) are two leading techniques for investigating the connectivity of the human brain. They have been widely used to investigate the strength of anatomical and functional connections between distant brain regions in healthy subjects, and in clinical populations. Though they are both based on magnetic resonance imaging (MRI) they have not yet been compared directly. In this work both techniques were employed to create global connectivity matrices covering the whole brain gray matter. This allowed for direct comparisons between functional connectivity measured by RSTC with anatomical connectivity quantified using DTI tractography. We found that connectivity matrices obtained using both techniques showed significant agreement. Connectivity maps created for a priori defined anatomical regions showed significant correlation, and furthermore agreement was especially high in regions showing strong overall connectivity, such as those belonging to the default mode network. Direct comparison between functional RSTC and anatomical DTI connectivity, presented here for the first time, links two powerful approaches for investigating brain connectivity and shows their strong agreement. It provides a crucial multi-modal validation for resting state correlations as representing neuronal connectivity. The combination of both techniques presented here allows for further combining them to provide richer representation of brain connectivity both in the healthy brain and in clinical conditions.
Benett, William J.; Andreski, John T.; Dzenitis, John M.; Makarewicz, Anthony J.; Hadley, Dean R.; Pannu, Satinderpall S.
2014-07-15
A thermalcycler includes a first thermalcycler body section having a first face and a second thermalcycler body section having a second face. A cavity is formed by the first face and the second face. A thermalcycling unit is positioned in the cavity. A heater trace unit is connected to a support section, to the first thermalcycler body section, to the second thermalcycler body section, and to the thermalcycling unit. The first thermalcycler body section and the second thermalcycler body section are positioned together against the support section to enclose the thermalcycling unit and the heater trace unit.
Split ring floating air riding seal for a turbine
Mills, Jacob A
2015-11-03
A floating air riding seal for a gas turbine engine with a rotor and a stator, an annular piston chamber with an axial moveable annular piston assembly within the annular piston chamber, an annular cavity formed on the annular piston assembly that faces a seal surface on the rotor, and a central passage connecting the annular cavity to the annular piston chamber to supply compressed air to the seal face, where the annular piston assembly is a split piston assembly to maintain a tight seal as coning of the rotor disk occurs.
Code of Federal Regulations, 2010 CFR
2010-04-01
... INVESTMENT ACT Community Connections § 670.800 How do Job Corps centers and service providers become involved... Community Liaison designated by the director of the center to establish relationships with local and distant... businesses with employment opportunities in the local area and the areas to which students will return. (f...
Code of Federal Regulations, 2011 CFR
2011-04-01
... INVESTMENT ACT Community Connections § 670.800 How do Job Corps centers and service providers become involved... Community Liaison designated by the director of the center to establish relationships with local and distant... businesses with employment opportunities in the local area and the areas to which students will return. (f...
Exploring World Cultures with Music
ERIC Educational Resources Information Center
Erler, Mary Frances
2004-01-01
As a music teacher, this author was always looking for good cross-curricular connections. Because music is something that all children enjoy to some degree, it is a great way to open new doors to a subject area. Music is an integral part of every culture, so it can be part of any unit of study on a foreign country or distant continent. Music can…
Wearable wireless photoplethysmography sensors
NASA Astrophysics Data System (ADS)
Spigulis, Janis; Erts, Renars; Nikiforovs, Vladimirs; Kviesis-Kipge, Edgars
2008-04-01
Wearable health monitoring sensors may support early detection of abnormal conditions and prevention of their consequences. Recent designs of three wireless photoplethysmography monitoring devices embedded in hat, glove and sock, and connected to PC or mobile phone by means of the Bluetooth technology, are described. First results of distant monitoring of heart rate and pulse wave transit time using the newly developed devices are presented.
ERIC Educational Resources Information Center
Torres, Sergio; Powers, Judith L.
2009-01-01
In the exciting, "out of this world" activity described here, students measure the Earth using meter sticks while measuring their shadows in two distant locations. To obtain the size of the Earth, students discover the connection between the measurements of the shadows and a model of the spherical Earth following the method developed by…
Modeling the size of the very dynamic diamagnetic cavity of comet 67P/Churyumov-Gerasimenko
NASA Astrophysics Data System (ADS)
Timar, Aniko; Nemeth, Zoltan; Madanian, Hadi; Glassmeier, Karl-Heinz; Goetz, Charlotte; Richter, Ingo; Szego, Karoly
2017-04-01
After the first detection of the diamagnetic cavity of comet 67P/Churyumov-Gerasimenko (Goetz et al. 2015) it became apparent that the boundary of this plasma region is very dynamic. To date hundreds of short cavity crossing events were detected (Nemeth et al. 2016, Goetz et al. in press), none lasting longer than an hour. This intermittent set of short crossing events is very different from the classical cavity observation near 1P/Halley, where Giotto remained for a long time continuously inside the cavity. The distance of the boundary is larger than that predicted by recent models, so it was not clear whether these short cavity-like regions are connected to a global diamagnetic cavity, or they are due to some local effects causing similar magnetic and plasma signatures. Here we revisit the neutral-drag model of Cravens 1986 to provide a very good phenomenological approximation for the highly variable size of this dynamic region. The model uses the cometary neutral production rate and the solar wind dynamic pressure as inputs. For the production rate we use averaged and detrended data derived from ROSINA neutral density measurements (Hansen et al. 2016). The solar wind pressure comes from space weather models and independently from the magnetic field measurements of MAG derived by using a method proposed by Madanian et al. 2016. The changes in the production rate and the dynamic pressure allows us to accurately predict the size of the cavity. In addition we show that instead of the local neutral pressure, the global production rate drives the size of the cavity. We can also explain the observed asymmetry between inbound and outbound crossings of the cavity boundary.
NASA Astrophysics Data System (ADS)
Rounds, Eric
The urban lowland areas of Vietnam have been at the forefront of economic liberalization over the last 30 years, while the more remote mountainous areas of the country have lagged behind. Upland areas in the Northern and Central portions of Vietnam in particular remain largely impoverished and disconnected from broader national and regional markets. To address this economic inequality in the uplands, recent economic development efforts such as the East-West Economic Corridor (EWEC) have aimed at expanding road infrastructure to remote areas in Central Vietnam. This study examines the impact of road expansion in the EWEC on a single village in Quang Tri, Vietnam. It draws from social economic data gathered during fieldwork and a historical land cover analysis to address how land use, land cover, and livelihoods have changed in recent decades. Moreover, the paper discusses the distal and proximate drivers of these changes. Findings show that the improved road connectivity provided by new roads has facilitated the transmission of distant market-related drivers into the study area, and that these drivers have fostered significant changes in land use, land cover, and livelihoods.
NASA Astrophysics Data System (ADS)
Zhang, Chun-Ling; Liu, Wen-Wu
2018-05-01
In this paper, combining transitionless quantum driving and quantum Zeno dynamics, we propose an efficient scheme to fast implement a two-qubit quantum phase gate which can be used to generate cluster state of atoms trapped in distant cavities. The influence of various of various error sources including spontaneous emission and photon loss on the fidelity is analyzed via numerical simulation. The results show that this scheme not only takes less time than adiabatic scheme but also is not sensitive to both error sources. Additionally, a creation of N-atom cluster states is put forward as a typical example of the applications of the phase gates.
NASA Astrophysics Data System (ADS)
Mondal, Sukanta; Goswami, Tamal; Jana, Gourhari; Misra, Anirban; Chattaraj, Pratim Kumar
2018-01-01
In this letter, a possible reason behind selective host-guest organization in the initial stage of sI methane hydrate nucleation is provided, through density functional theory based calculations. In doing so, we have connected earlier experimental and theoretical observations on the structure and energetics of sI methane hydrate to our findings. Geometry and relative stability of small (H2O)5 and (H2O)6 clusters, presence of CH4 guest, integrity and cavity radius of (H2O)20 and (H2O)24, as well as the weak van der Waals type of forces, particularly dispersion interaction, are major factors responsible for initial formation of methane encapsulated dodecahedron cavity over tetrakaidecahedron.
Passive tire pressure sensor and method
Pfeifer, Kent Bryant; Williams, Robert Leslie; Waldschmidt, Robert Lee; Morgan, Catherine Hook
2006-08-29
A surface acoustic wave device includes a micro-machined pressure transducer for monitoring tire pressure. The device is configured having a micro-machined cavity that is sealed with a flexible conductive membrane. When an external tire pressure equivalent to the cavity pressure is detected, the membrane makes contact with ridges on the backside of the surface acoustic wave device. The ridges are electrically connected to conductive fingers of the device. When the detected pressure is correct, selected fingers on the device will be grounded producing patterned acoustic reflections to an impulse RF signal. When the external tire pressure is less than the cavity reference pressure, a reduced reflected signal to the receiver results. The sensor may further be constructed so as to identify itself by a unique reflected identification pulse series.
Passive tire pressure sensor and method
Pfeifer, Kent Bryant; Williams, Robert Leslie; Waldschmidt, Robert Lee; Morgan, Catherine Hook
2007-09-04
A surface acoustic wave device includes a micro-machined pressure transducer for monitoring tire pressure. The device is configured having a micro-machined cavity that is sealed with a flexible conductive membrane. When an external tire pressure equivalent to the cavity pressure is detected, the membrane makes contact with ridges on the backside of the surface acoustic wave device. The ridges are electrically connected to conductive fingers of the device. When the detected pressure is correct, selected fingers on the device will be grounded producing patterned acoustic reflections to an impulse RF signal. When the external tire pressure is less than the cavity reference pressure, a reduced reflected signal to the receiver results. The sensor may further be constructed so as to identify itself by a unique reflected identification pulse series.
Nucleoli and stress granules: connecting distant relatives.
Mahboubi, Hicham; Stochaj, Ursula
2014-10-01
Nucleoli and cytoplasmic stress granules (SGs) are subcellular compartments that modulate the response to endogenous and environmental signals to control cell survival. In our opinion, nucleoli and SGs are functionally linked; they are distant relatives that combine forces when cellular homeostasis is threatened. Several lines of evidence support this idea; nucleoli and SGs share molecular building blocks, are regulated by common signaling pathways and communicate when vital cellular functions become compromised. Together, nucleoli and SGs orchestrate physiological responses that are directly relevant to stress and human health. As both compartments have established roles in neurodegenerative diseases, cancer and virus infections, we propose that these conditions will benefit from therapeutic interventions that target simultaneously nucleoli and SGs. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
[Neuroeffector connections of multimodal neurons in the African snail (Achatina fulica)].
Bugaĭ, V V; Zhuravlev, V L; Safonova, T A
2004-02-01
Using a new method of animal preparation, the efferent connections of giant paired neurons on the dorsal surface of visceral and right parietal ganglia of snail, Achatina fulica, were examined. It was found that spikes in giant neurons d-VLN and d-RPLN evoke postjunctional potentials in different points of the snail body and viscerae (in the heart, in pericardium, in lung cavity and kidney walls, in mantle and body wall muscles, in tentacle retractors and in cephalic artery). The preliminary analysis of synaptic latency and facilitation suggests a direct connections between giant neurons and investigated efferents.
Pool boiling on surfaces with mini-fins and micro-cavities
NASA Astrophysics Data System (ADS)
Pastuszko, Robert; Piasecka, Magdalena
2012-11-01
The experimental studies presented here focused on pool boiling heat transfer on mini-fin arrays, mini-fins with perforated covering and surfaces with micro-cavities. The experiments were carried out for water and fluorinert FC-72 at atmospheric pressure. Mini-fins of 0.5 and 1 mm in height were uniformly spaced on the base surface. The copper foil with holes of 0.1 mm in diameter (pitch 0.2/0.4 mm), sintered with the fin tips, formed a system of connected perpendicular and horizontal tunnels. The micro-cavities were obtained through spark erosion. The maximal depth of the craters of these cavities was 15 - 30 μm and depended on the parameters of the branding-pen settings. At medium and small heat fluxes, structures with mini-fins showed the best boiling heat transfer performance both for water and FC-72. At medium and high heat fluxes (above 70 kW/m2 for water and 25 kW/m2 for FC-72), surfaces with mini-fins without porous covering and micro-cavities produced the highest heat transfer coefficients. The surfaces obtained with spark erosion require a proper selection of geometrical parameters for particular liquids - smaller diameters of cavities are suitable for liquids with lower surface tension (FC-72).
Davy, John L
2010-02-01
This paper presents a revised theory for predicting the sound insulation of double leaf cavity walls that removes an approximation, which is usually made when deriving the sound insulation of a double leaf cavity wall above the critical frequencies of the wall leaves due to the airborne transmission across the wall cavity. This revised theory is also used as a correction below the critical frequencies of the wall leaves instead of a correction due to Sewell [(1970). J. Sound Vib. 12, 21-32]. It is found necessary to include the "stud" borne transmission of the window frames when modeling wide air gap double glazed windows. A minimum value of stud transmission is introduced for use with resilient connections such as steel studs. Empirical equations are derived for predicting the effective sound absorption coefficient of wall cavities without sound absorbing material. The theory is compared with experimental results for double glazed windows and gypsum plasterboard cavity walls with and without sound absorbing material in their cavities. The overall mean, standard deviation, maximum, and minimum of the differences between experiment and theory are -0.6 dB, 3.1 dB, 10.9 dB at 1250 Hz, and -14.9 dB at 160 Hz, respectively.
Method of fabricating conductive electrodes on the front and backside of a thin film structure
Tabada, Phillipe J [Roseville, CA; Tabada, legal representative, Melody; Pannu, Satinderpall S [Pleasanton, CA
2011-05-22
A method of fabricating a thin film device having conductive front and backside electrodes or contacts. Top-side cavities are first formed on a first dielectric layer, followed by the deposition of a metal layer on the first dielectric layer to fill the cavities. Defined metal structures are etched from the metal layer to include the cavity-filled metal, followed by depositing a second dielectric layer over the metal structures. Additional levels of defined metal structures may be formed in a similar manner with vias connecting metal structures between levels. After a final dielectric layer is deposited, a top surface of a metal structure of an uppermost metal layer is exposed through the final dielectric layer to form a front-side electrode, and a bottom surface of a cavity-filled portion of a metal structure of a lowermost metal layer is also exposed through the first dielectric layer to form a back-side electrode.
Oral Bilateral Collagenous Fibroma: A previously unreported case and literature review.
Vasconcelos, Ana-Carolina; Gomes, Ana-Paula; Tarquinio, Sandra; Abduch-Rodrigues, Eduardo; Mesquita, Ricardo; Silva, Karine
2018-01-01
Collagenous fibroma, also known as desmoplastic fibroblastoma, is a rare benign slow growing tumor particularly uncommon in the oral cavity. The aim of this study was to analyze the clinical and histopathological features of an oral collagenous fibroma as well as to compare this data with those reported in an English-literature review. The thirteenth case of collagenous fibroma in the oral cavity and the first to present clinically as a bilateral mass was described. A 48-years-old female patient was referred to a School of Dentistry, complaining about an asymptomatic swelling on the hard palate, lasting around ten years. The intraoral examination revealed two well-defined mass, bilaterally in the hard palate. An excisional biopsy was performed. Microscopically, the connective tissue consisted of dense collagen bundles in which were seen scarcely distributed spindle-shaped to stellate fibroblastic cells. Blood vessels were few, as well as inflammatory cells. Immunohistochemical staining was positive for vimentin, α-smooth muscle actin and factor XIIIa and negative for S-100, CD68, CD34, HHF35, desmin and AE1/AE3. The patient remains disease-free 24 months after excision. In conclusion, oral collagenous fibroma should be included in the differential diagnosis of bilateral sessile nodules in the oral cavity. Key words: Connective tissue, mouth diseases, mouth neoplasms, oral diagnosis, oral pathology.
Microliter-sized ionization device and method
NASA Technical Reports Server (NTRS)
Simac, Robert M. (Inventor); Wernlund, Roger F. (Inventor); Cohen, Martin J. (Inventor)
1999-01-01
A microliter-sized metastable ionization device with a cavity, a sample gas inlet, a corona gas inlet and a gas outlet. A first electrode has a hollow and disposed in the cavity and is in fluid communication with the sample gas inlet. A second electrode is in fluid communication with the corona gas inlet and is disposed around the first electrode adjacent the hollow end thereof. A gap forming means forms a corona gap between the first and second electrodes. A first power supply is connected to the first electrode and the second power supply is connected to the second electrode for generating a corona discharge across the corona gap. A collector has a hollow end portion disposed in the cavity which is in fluid communications with the gas outlet for the outgassing and detection of ionized gases. The first electrode can be a tubular member aligned concentrically with a cylindrical second electrode. The gap forming means can be in annular disc projecting radially inwardly from the cylindrical second electrode. The collector can have a tubular opening aligned coaxially with the first electrode and has an end face spaced a short distance from an end face of the first electrode forming a small active volume therebetween for the generation and detection of small quantities of trace analytes.
ERIC Educational Resources Information Center
Northwest Regional Educational Lab., Portland, OR. Education, Career, and Community Program.
These guides are part of a toolkit designed to help young people make connections between the jobs they now hold, the classes they are taking, and the goals they may have for the near and distant future. The guides contain a variety of materials and activities appropriate for all skill levels. The activities in the student guide are grounded in…
Demonstration of acoustic resonances in a cylindrical cavity applying the photoacoustic technique
NASA Astrophysics Data System (ADS)
Barreiro, N. L.; Vallespi, A. S.; Zajarevich, N. M.; Peuriot, A. L.; Slezak, V. B.
2017-09-01
In this work we present some experiments which can be performed in college or on the first courses of university to acquire knowledge about resonant acoustical phenomena in closed cavities in a tangible way, through experiments based on the photoacoustic effect in gases. This phenomenon consists in the generation of acoustic waves after optical excitation of an absorbing gas and further local heating of the non-absorbing surrounding gas by energy exchange through collisions between molecules of both species. Simple experiments, performed with daily live elements, can be very useful for teachers and students to get in touch with the phenomenon of acoustic resonances with the addition of concepts about light-matter interaction. The setups consist of the resonant cavity, the illumination source and the signal detection-acquisition scheme. In this paper a closed glass test tube is used as the resonant cavity and is filled with a mixture of nitrogen dioxide and air. The illumination is performed by a pulsed power LED modulated at different resonant frequencies of the cavity. A microphone inside the tube is connected to an oscilloscope which displays the photoacoustic signal. The LED is moved along the tube showing how different resonant modes can be excited.
Equine nasal and paranasal sinus tumours: part 2: a contribution of 28 case reports.
Dixon, P M; Head, K W
1999-05-01
The clinical and pathological findings of 28 cases (27 horses, 1 donkey) of equid sinonasal tumours examined at the Edinburgh Veterinary School are presented and include: seven cases of squamous cell carcinoma (SCC); five adenocarcinomas; three undifferentiated carcinomas; two adenomas; five fibro-osseous and bone tumours; and single cases of ameloblastoma, fibroma, fibrosarcoma, undifferentiated sarcoma, melanoma and lymphosarcoma. The median ages of animals affected with epithelial, and fibro-osseous/bone tumours were 14 and 4 years, respectively. Unilateral purulent or mucopurulent nasal discharge (81% of cases) and gross facial swellings (82% of cases) were the most common presenting signs with sinonasal tumours, with epistaxis recorded in just 23% of cases. Radiology and endoscopy were the most useful ancillary diagnostic techniques. The maxillary area was the most common site of tumour origin, and only three cases were definitively identified as originating in the nasal cavity. Four of the maxillary SCC lesions originated within the nasal cavities or maxillary sinuses, while two originated in the oral cavity. Fourteen of 15 carcinomas, but only two of the 13 remaining tumours, spread to other sites in the head. Only three cases of sinonasal tumour had lymph node metastases, and none had distant metastases. In the long term, surgical treatment with seven malignant tumours was unsuccessful (6 months median survival post-operatively), but was successful with four out of five benign tumours (no regrowth at a median of 4 years post-operatively).
Sinonasal adenoid cystic carcinoma: a population-based analysis of 694 cases.
Unsal, Aykut A; Chung, Sei Y; Zhou, Albert H; Baredes, Soly; Eloy, Jean Anderson
2017-03-01
Currently, limited literature exists about sinonasal adenoid cystic carcinoma (SNACC). In this study, we analyze the demographics, survival, and treatment efficacy of this rare entity. Our study was a retrospective population-based analysis of SNACC in the Surveillance, Epidemiology, and End Results (SEER) database assessing the 40-year time-frame of 1973 to 2013. Six hundred ninety-four SNACC patients were identified; 53.2% were female and 46.8% were male. Caucasians were most commonly affected (77.1%). SNACC most often arose from the maxillary sinuses, followed by the nasal cavity. The majority of SNACC cases presented as stage IV disease. Nodal and distant metastases were present in 3.6% and 7.1% of all cases, respectively. Overall 5-, 10-, and 20-year disease-specific survival (DSS) rates were 66.5%, 41.1%, and 17.6%, respectively. The presence of distant metastasis dropped the 5-year DSS rate from 64.5% to 20.0%. Cases treated with combined surgery and adjuvant radiotherapy had a slightly improved 5-year DSS rate compared with surgery alone (73.5% vs 72.5%). Surgery alone resulted in higher 10- and 20-year DSS rates (54.2% and 36.8%, respectively) when compared with combined therapy (44.2% and 15.5%), radiotherapy alone (10.8% and 0%), and no surgery or radiotherapy (9.3% and 0%). This study represents the largest cohort of SNACC patients to date. Factors that confer a survival benefit in SNACC include M0 disease, and presentation primarily in the nasal cavity. Overall low rates of nodal metastasis may not warrant the use of elective neck dissections, unless there is clinical suspicion. Modalities of therapy that include surgery greatly improve survival. Adjuvant radiotherapy appears to slightly improve 5-year disease-free survival but does not impact long-term survival. © 2016 ARS-AAOA, LLC.
NASA Astrophysics Data System (ADS)
Ma, Cheng-Jiun; McNamara, B.; Nulsen, P.; Schaffer, R.
2011-09-01
X-ray observations of nearby clusters and galaxies have shown that energetic feedback from AGN is heating hot atmospheres and is probably the principal agent that is offsetting cooling flows. Here we examine AGN heating in distant X-ray clusters by cross correlating clusters selected from the 400 Square Degree X-ray Cluster survey with radio sources in the NRAO VLA Sky Survey. The jet power for each radio source was determined using scaling relations between radio power and cavity power determined for nearby clusters, groups, and galaxies with atmospheres containing X-ray cavities. Roughly 30% of the clusters show radio emission above a flux threshold of 3 mJy within the central 250 kpc that is presumably associated with the brightest cluster galaxy. We find no significant correlation between radio power, hence jet power, and the X-ray luminosities of clusters in redshift range 0.1 -- 0.6. The detection frequency of radio AGN is inconsistent with the presence of strong cooling flows in 400SD, but cannot rule out the presence of weak cooling flows. The average jet power of central radio AGN is approximately 2 10^{44} erg/s. The jet power corresponds to an average heating of approximately 0.2 keV/particle for gas within R_500. Assuming the current AGN heating rate remained constant out to redshifts of about 2, these figures would rise by a factor of two. Our results show that the integrated energy injected from radio AGN outbursts in clusters is statistically significant compared to the excess entropy in hot atmospheres that is required for the breaking of self-similarity in cluster scaling relations. It is not clear that central AGN in 400SD clusters are maintained by a self-regulated feedback loop at the base of a cooling flow. However, they may play a significant role in preventing the development of strong cooling flows at early epochs.
Displacement sensor based on intra-cavity tuning of dual-frequency gas laser
NASA Astrophysics Data System (ADS)
Niu, Haisha; Niu, Yanxiong; Liu, Ning; Li, Jiyang
2018-01-01
A nanometer-resolution displacement measurement instrument based on tunable cavity frequency-splitting method is presented. One beam is split into two orthogonally polarized beams when anisotropic element inserted in the cavity. The two beams with fixed frequency difference are modulated by the movement of the reflection mirror. The changing law of the power tuning curves between the total output and the two orthogonally polarized beams is researched, and a method splitting one tuning cycle to four equal parts is proposed based on the changing law, each part corresponds to one-eighth wavelength of displacement. A laser feedback interferometer (LFI) and piezoelectric ceramic are series connected to the sensor head to calibrate the displacement that less than one-eighth wavelength. The displacement sensor achieves to afford measurement range of 20mm with resolution of 6.93nm.
Comparative population structure of cavity-nesting sea ducks
Pearce, John M.; Eadie, John M.; Savard, Jean-Pierre L.; Christensen, Thomas K.; Berdeen, James; Taylor, Eric J.; Boyd, Sean; Einarsson, Árni
2014-01-01
A growing collection of mtDNA genetic information from waterfowl species across North America suggests that larger-bodied cavity-nesting species exhibit greater levels of population differentiation than smaller-bodied congeners. Although little is known about nest-cavity availability for these species, one hypothesis to explain differences in population structure is reduced dispersal tendency of larger-bodied cavity-nesting species due to limited abundance of large cavities. To investigate this hypothesis, we examined population structure of three cavity-nesting waterfowl species distributed across much of North America: Barrow's Goldeneye (Bucephala islandica), Common Goldeneye (B. clangula), and Bufflehead (B. albeola). We compared patterns of population structure using both variation in mtDNA control-region sequences and band-recovery data for the same species and geographic regions. Results were highly congruent between data types, showing structured population patterns for Barrow's and Common Goldeneye but not for Bufflehead. Consistent with our prediction, the smallest cavity-nesting species, the Bufflehead, exhibited the lowest level of population differentiation due to increased dispersal and gene flow. Results provide evidence for discrete Old and New World populations of Common Goldeneye and for differentiation of regional groups of both goldeneye species in Alaska, the Pacific Northwest, and the eastern coast of North America. Results presented here will aid management objectives that require an understanding of population delineation and migratory connectivity between breeding and wintering areas. Comparative studies such as this one highlight factors that may drive patterns of genetic diversity and population trends.
Choudhary, Deepanshu; Panjikar, Santosh; Anand, Ruchi
2013-01-01
Formylglycinamide ribonucleotide amidotransferase (FGAR-AT) is a 140 kDa bi-functional enzyme involved in a coupled reaction, where the glutaminase active site produces ammonia that is subsequently utilized to convert FGAR to its corresponding amidine in an ATP assisted fashion. The structure of FGAR-AT has been previously determined in an inactive state and the mechanism of activation remains largely unknown. In the current study, hydrophobic cavities were used as markers to identify regions involved in domain movements that facilitate catalytic coupling and subsequent activation of the enzyme. Three internal hydrophobic cavities were located by xenon trapping experiments on FGAR-AT crystals and further, these cavities were perturbed via site-directed mutagenesis. Biophysical characterization of the mutants demonstrated that two of these three voids are crucial for stability and function of the protein, although being ∼20 Å from the active centers. Interestingly, correlation analysis corroborated the experimental findings, and revealed that amino acids lining the functionally important cavities form correlated sets (co-evolving residues) that connect these regions to the amidotransferase active center. It was further proposed that the first cavity is transient and allows for breathing motion to occur and thereby serves as an allosteric hotspot. In contrast, the third cavity which lacks correlated residues was found to be highly plastic and accommodated steric congestion by local adjustment of the structure without affecting either stability or activity. PMID:24223728
High-power radio-frequency attenuation device
Kerns, Q.A.; Miller, H.W.
1981-12-30
A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.
The revised anatomy of the canals connecting the orbit with the cranial cavity.
Regoli, Marì; Bertelli, Eugenio
2017-04-01
Orbits are connected with the middle cranial fossa via the optic canal, the superior orbital fissure, the M-type orbitomeningeal foramen, the metoptic canal, an accessory anterior opening of the foramen rotundum, and Warwick's canal. They are also in communication with the anterior cranial fossa via the ethmoidal canals and the A-type orbitomeningeal foramen. The anatomy of these conduits has been recently enriched with several details that are summarized and reviewed in this article.
High power radio frequency attenuation device
Kerns, Quentin A.; Miller, Harold W.
1984-01-01
A resistor device for attenuating radio frequency power includes a radio frequency conductor connected to a series of fins formed of high relative magnetic permeability material. The fins are dimensional to accommodate the skin depth of the current conduction therethrough, as well as an inner heat conducting portion where current does not travel. Thermal connections for air or water cooling are provided for the inner heat conducting portions of each fin. Also disclosed is a resistor device to selectively alternate unwanted radio frequency energy in a resonant cavity.
A teleconference with three-dimensional surgical video presentation on the 'usual' Internet.
Obuchi, Toshiro; Moroga, Toshihiko; Nakamura, Hiroshige; Shima, Hiroji; Iwasaki, Akinori
2015-03-01
Endoscopic surgery employing three-dimensional (3D) video images, such as a robotic surgery, has recently become common. However, the number of opportunities to watch such actual 3D videos is still limited due to many technical difficulties associated with showing 3D videos in front of an audience. A teleconference with 3D video presentations of robotic surgeries was held between our institution and a distant institution using a commercially available telecommunication appliance on the 'usual' Internet. Although purpose-built video displays and 3D glasses were necessary, no technical problems occurred during the presentation and discussion. This high-definition 3D telecommunication system can be applied to discussions about and education on 3D endoscopic surgeries for many surgeons, even in distant places, without difficulty over the usual Internet connection.
Reciprocal Symbiont Sharing in the Lodging Mutualism between Walking Corals and Sipunculans.
Igawa, Momoko; Hata, Hiroki; Kato, Makoto
2017-01-01
Solitary scleractinian corals of the genera Heterocyathus and Heteropsammia inhabit soft marine bottoms without attaching to hard substrata. The corallums of these genera contain a coiled cavity inhabited by a sipunculan that roams the seafloor, carrying the host coral with it. The coral serves as a sturdy shelter that protects the sipunculan from possible predators. At the same time, the sipunculan maintains the coral in an upright position on the soft bottom. This coral-sipunculan association is unique because two phylogenetically distant coral genera have developed convergent associations with sipunculans. We investigate the process of convergent evolution of two coral species, Hc. aequicostatus and Hp. cochlea, in Okinawa, Japan, with their symbiotic sipunculans, using phylogenetic and morphological analyses. Phylogenetic analyses clarified that the symbiotic sipunculans comprise two distinct clades, surprisingly both of which are associated with both coral species. The bodily habitus of the sipunculan differed between coral species and fit the morphologies of the coiled cavities of their respective host corals. Our results suggest that the two coral species share two sipunculan clades and that sipunculan morphology is plastic and determined by the internal structure of their host corals.
Method and device for microwave sintering large ceramic articles
Kimrey, Jr., Harold D.
1990-01-01
A microwave sintering system and method are provided for extremely uniform sintering of large and/or irregular shaped ceramic articles at microwave frequencies of at least 28 GHz in the hundreds of kilowatts power range in an untuned cavity. A 28 GHz, 200 kw gyrotron with variable power output is used as the microwave source connected to an untuned microwave cavity formed of an electrically conductive housing through an overmoded waveguide arrangement which acts in conjunction with a mode promoter within the cavity to achieve unexpected field uniformity. The part to be sintered is placed in the cavity and supported on a removable high temperature table in a central location within the cavity. The part is surrounded by a microwave transparent bulk insulating material to reduce thermal heat loss at the part surfaces and maintain more uniform temperature. The cavity may be operated at a high vacuum to aid in preventing arcing. The system allows controlled increased heating rates of greater than 200.degree. C./min to provide rapid heating of a ceramic part to a selected sintering temperature where it is maintained by regulating the microwave power applied to the part. As a result of rapid heating, the extent of non-isothermal processes such as segregation of impurities to the grain boundaries are minimized and exaggerated grain growth is reduced, thereby strengthening the mechanical properties of the ceramic part being sintered.
Hadad, Bat-Sheva; Kimchi, Ruth
2006-11-01
In two experiments, visual search was used to study the grouping of shape on the basis of perceptual closure among participants 5-23 years of age. We first showed that young children, like adults, demonstrate an efficient search for a concave target among convex distractors for closed connected stimuli but an inefficient search for open stimuli. Reliable developmental differences, however, were observed in search for fragmented stimuli as a function of spatial proximity and collinearity between the closure-inducing fragments. When only closure was available, search for all the age groups was equally efficient for spatially close fragments and equally inefficient for spatially distant fragments. When closure and collinearity were available, search for spatially close fragments was equally efficient for all the age groups, but search for spatially distant fragments was inefficient for younger children and improved significantly between ages 5 and 10. These findings suggest that young children can utilize closure as efficiently as can adults for the grouping of shape for closed or nearly closed stimuli. When the closure-inducing fragments are spatially distant, only older children and adults, but not 5-year-olds, can utilize collinearity to enhance closure for the perceptual grouping of shape.
Electrocortical correlations between pairs of isolated people: A reanalysis
Radin, Dean
2017-01-01
A previously reported experiment collected electrocortical data recorded simultaneously in pairs of people separated by distance. Reanalysis of those data confirmed the presence of a time-synchronous, statistically significant correlation in brain electrical activity of these distant “sender-receiver” pairs. Given the sensory shielding employed in the original experiment to avoid mundane explanations for such a correlation, this outcome is suggestive of an anomalous intersubjective connection. PMID:28713556
ERIC Educational Resources Information Center
Muszkat-Barkan, Michal; Grant, Lisa D.
2015-01-01
This research explores the impact of a year studying in Israel on Hebrew Union College-Jewish Institute of Religion (HUC-JIR) rabbinical students' emotional connection toward and knowledge about the State of Israel and the Jewish People. We want to better understand the students' beliefs, ideas, and behaviors that emerge from their experience…
Hoppock, David C; Patiño-Echeverri, Dalia
2010-11-15
The best wind sites in the United States are often located far from electricity demand centers and lack transmission access. Local sites that have lower quality wind resources but do not require as much power transmission capacity are an alternative to distant wind resources. In this paper, we explore the trade-offs between developing new wind generation at local sites and installing wind farms at remote sites. We first examine the general relationship between the high capital costs required for local wind development and the relatively lower capital costs required to install a wind farm capable of generating the same electrical output at a remote site,with the results representing the maximum amount an investor should be willing to pay for transmission access. We suggest that this analysis can be used as a first step in comparing potential wind resources to meet a state renewable portfolio standard (RPS). To illustrate, we compare the cost of local wind (∼50 km from the load) to the cost of distant wind requiring new transmission (∼550-750 km from the load) to meet the Illinois RPS. We find that local, lower capacity factor wind sites are the lowest cost option for meeting the Illinois RPS if new long distance transmission is required to access distant, higher capacity factor wind resources. If higher capacity wind sites can be connected to the existing grid at minimal cost, in many cases they will have lower costs.
Birkefeld, Anja Britta; Bertermann, Rüdiger; Eckert, Hellmut; Pfleiderer, Bettina
2003-01-01
To investigate aging processes of silicone gel breast implants, which may include migration of free unreacted material from the gel and rubber to local (e.g. connective tissue capsule) or distant sites in the body, chemical alteration of the polymer and infiltration of body compounds, various approaches of multinuclear nuclear magnetic resonance (NMR) experiments (29Si, 13C, 1H) were evaluated. While 29Si, 13C, and 1H solid-state magic angle spinning (MAS) NMR techniques performed on virgin and explanted envelopes of silicone prostheses provided only limited information, high-resolution liquid-state NMR techniques of CDCl(3) extracts were highly sensitive analytical tools for the detection of aging related changes in the materials. Using 2D 1H, 1H correlation spectroscopy (COSY) and 29Si, 1H heteronuclear multiple bond coherence (HMBC) experiments with gradient selection, it was possible to detect lipids (mainly phospholipids) as well as silicone oligomer species in explanted envelopes and gels. Silicone oligomers were also found in connective tissue capsules, indicating that cyclic polysiloxanes can migrate from intact implants to adjacent and distant sites. Furthermore, lipids can permeate the implant and modify its chemical composition. Copyright 2002 Elsevier Science Ltd.
Transmission of live laparoscopic surgery over the Internet2.
Damore, L J; Johnson, J A; Dixon, R S; Iverson, M A; Ellison, E C; Melvin, W S
1999-11-01
Video broadcasting of surgical procedures is an important tool for education, training, and consultation. Current video conferencing systems are expensive and time-consuming and require preplanning. Real-time Internet video is known for its poor quality and relies on the equipment and the speed of the connection. The Internet2, a new high-speed (up to 2,048 Mbps), large bandwidth data network presently connects more than 100 universities and corporations. We have successfully used the Internet2 to broadcast the first real-time, high-quality audio/video program from a live laparoscopic operation to distant points. Video output of the laparoscopic camera and audio from a wireless microphone were broadcast to distant sites using a proprietary, PC-based implementation of H.320 video conferencing over a TCP/IP network connected to the Internet2. The receiving sites participated in two-way, real-time video and audio communications and graded the quality of the signal they received. On August 25, 1998, a laparoscopic Nissen fundoplication was transmitted to Internet2 stations in Colorado, Pennsylvania, and to an Internet station in New York. On September 28 and 29, 1998, we broadcast laparoscopic operations throughout both days to the Internet2 Fall Conference in San Francisco, California. Most recently, on February 24, 1999, we transmitted a laparoscopic Heller myotomy to the Abilene Network Launch Event in Washington, DC. The Internet2 is currently able to provide the bandwidth needed for a turn-key video conferencing system with high-resolution, real-time transmission. The system could be used for a variety of teaching and educational programs for experienced surgeons, residents, and medical students.
Fluid lubricated bearing assembly
Boorse, Henry A.; Boeker, Gilbert F.; Menke, John R.
1976-01-01
1. A support for a loaded rotatable shaft comprising in combination on a housing having a fluid-tight cavity encasing an end portion of said shaft, a thrust bearing near the open end of said cavity for supporting the axial thrust of said shaft, said thrust bearing comprising a thrust plate mounted in said housing and a thrust collar mounted on said shaft, said thrust plate having a central opening the peripheral portion of which is hermetically sealed to said housing at the open end of said cavity, and means for supplying a fluid lubricant to said thrust bearing, said thrust bearing having a lubricant-conducting path connecting said lubricant supplying means with the space between said thrust plate and collar intermediate the peripheries thereof, the surfaces of said plate and collar being constructed and arranged to inhibit radial flow of lubricant and, on rotation of said thrust collar, to draw lubricant through said path between the bearing surfaces and to increase the pressure therebetween and in said cavity and thereby exert a supporting force on said end portion of said shaft.
Fabry-Perot resonators with transverse coupling on SOI using loop mirrors
NASA Astrophysics Data System (ADS)
Saber, Md Ghulam; Abadía, Nicolás; Wang, Yun; Plant, David V.
2018-05-01
A novel integrated transversely coupled Fabry-Perot resonator using loop mirrors as the end reflectors are demonstrated via simulations and experiments on the silicon-on-insulator (SOI) platform. The resonator is formed by connecting two loop mirrors to the two output ports of a directional coupler to form the resonant cavity and utilizing the other two ports as the input and the output. Depending on which two ports of the directional coupler are mirrored, two configurations of the resonator can be achieved. The impacts of varying the cavity length and the coupling coefficient of the directional coupler on the output characteristics of the resonators are analyzed. A Q-factor of 28086 and an extinction ratio of 10.04 dB with an insertion loss of 1.9 dB is achieved experimentally for a 1038 μm cavity length and an extinction ratio of 18.14 dB and a Q-factor of 5120 with an insertion loss of 2.12 dB is obtained for a cavity length of 376 μm. The reported resonator offers additional freedom to tune the spectral characteristics.
Self-contained sub-millimeter wave rectifying antenna integrated circuit
NASA Technical Reports Server (NTRS)
Siegel, Peter H. (Inventor)
2004-01-01
The invention is embodied in a monolithic semiconductor integrated circuit in which is formed an antenna, such as a slot dipole antenna, connected across a rectifying diode. In the preferred embodiment, the antenna is tuned to received an electromagnetic wave of about 2500 GHz so that the device is on the order of a wavelength in size, or about 200 microns across and 30 microns thick. This size is ideal for mounting on a microdevice such as a microrobot for example. The antenna is endowed with high gain in the direction of the incident radiation by providing a quarter-wavelength (30 microns) thick resonant cavity below the antenna, the cavity being formed as part of the monolithic integrated circuit. Preferably, the integrated circuit consists of a thin gallium arsenide membrane overlying the resonant cavity and supporting an epitaxial Gallium Arsenide semiconductor layer. The rectifying diode is a Schottky diode formed in the GaAs semiconductor layer and having an area that is a very small fraction of the wavelength of the 2500 GHz incident radiation. The cavity provides high forward gain in the antenna and isolation from surrounding structure.
Three-dimensional reconstruction of rat knee joint using episcopic fluorescence image capture.
Takaishi, R; Aoyama, T; Zhang, X; Higuchi, S; Yamada, S; Takakuwa, T
2014-10-01
Development of the knee joint was morphologically investigated, and the process of cavitation was analyzed by using episcopic fluorescence image capture (EFIC) to create spatial and temporal three-dimensional (3D) reconstructions. Knee joints of Wister rat embryos between embryonic day (E)14 and E20 were investigated. Samples were sectioned and visualized using an EFIC. Then, two-dimensional image stacks were reconstructed using OsiriX software, and 3D reconstructions were generated using Amira software. Cavitations of the knee joint were constructed from five divided portions. Cavity formation initiated at multiple sites at E17; among them, the femoropatellar cavity (FPC) was the first. Cavitations of the medial side preceded those of the lateral side. Each cavity connected at E20 when cavitations around the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) were completed. Cavity formation initiated from six portions. In each portion, development proceeded asymmetrically. These results concerning anatomical development of the knee joint using EFIC contribute to a better understanding of the structural feature of the knee joint. Copyright © 2014 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Hardware-efficient fermionic simulation with a cavity-QED system
NASA Astrophysics Data System (ADS)
Zhu, Guanyu; Subaşı, Yiǧit; Whitfield, James D.; Hafezi, Mohammad
2018-03-01
In digital quantum simulation of fermionic models with qubits, non-local maps for encoding are often encountered. Such maps require linear or logarithmic overhead in circuit depth which could render the simulation useless, for a given decoherence time. Here we show how one can use a cavity-QED system to perform digital quantum simulation of fermionic models. In particular, we show that highly nonlocal Jordan-Wigner or Bravyi-Kitaev transformations can be efficiently implemented through a hardware approach. The key idea is using ancilla cavity modes, which are dispersively coupled to a qubit string, to collectively manipulate and measure qubit states. Our scheme reduces the circuit depth in each Trotter step of the Jordan-Wigner encoding by a factor of N2, comparing to the scheme for a device with only local connectivity, where N is the number of orbitals for a generic two-body Hamiltonian. Additional analysis for the Fermi-Hubbard model on an N × N square lattice results in a similar reduction. We also discuss a detailed implementation of our scheme with superconducting qubits and cavities.
Packing loops into annular cavities.
Sobral, T A; Gomes, M A F
2017-02-01
The continuous packing of a flexible rod in two-dimensional cavities yields a countable set of interacting domains that resembles nonequilibrium cellular systems and belongs to a new class of lightweight material. However, the link between the length of the rod and the number of domains requires investigation, especially in the case of non-simply connected cavities, where the number of avoided regions emulates an effective topological temperature. In the present article we report the results of an experiment of injection of a single flexible rod into annular cavities in order to find the total length needed to insert a given number of loops (domains of one vertex). Using an exponential model to describe the experimental data we quite minutely analyze the initial conditions, the intermediary behavior, and the tight packing limit. This method allows the observation of a new fluctuation phenomenon associated with instabilities in the dynamic evolution of the packing process. Furthermore, the fractal dimension of the global pattern enters the discussion under a novel point of view. A comparison with the classical problems of the random close packing of disks and jammed disk packings is made.
Packing loops into annular cavities
NASA Astrophysics Data System (ADS)
Sobral, T. A.; Gomes, M. A. F.
2017-02-01
The continuous packing of a flexible rod in two-dimensional cavities yields a countable set of interacting domains that resembles nonequilibrium cellular systems and belongs to a new class of lightweight material. However, the link between the length of the rod and the number of domains requires investigation, especially in the case of non-simply connected cavities, where the number of avoided regions emulates an effective topological temperature. In the present article we report the results of an experiment of injection of a single flexible rod into annular cavities in order to find the total length needed to insert a given number of loops (domains of one vertex). Using an exponential model to describe the experimental data we quite minutely analyze the initial conditions, the intermediary behavior, and the tight packing limit. This method allows the observation of a new fluctuation phenomenon associated with instabilities in the dynamic evolution of the packing process. Furthermore, the fractal dimension of the global pattern enters the discussion under a novel point of view. A comparison with the classical problems of the random close packing of disks and jammed disk packings is made.
DOE Office of Scientific and Technical Information (OSTI.GOV)
J.K. Sekutowicz, P. Kneisel
This paper reports about our efforts to develop a flangeable coaxial coupler for both HOM and fundamental coupling for 9-cell TESLA/ILC-type cavities. The cavities were designed in early 90‘s for pulsed operation with a low duty factor, less than 1 %. The proposed design of the coupler has been done in a way, that the magnetic flux B at the flange connection is minimized and only a field of <5 mT would be present at the accelerating field Eacc of ~ 36 MV/m (B =150 mT in the cavity). Even though we achieved reasonably high Q-values at low field, themore » cavity/coupler combination was limited in the cw mode to only ~ 7 MV/m, where a thermally initiated degradation occurred. We have improved the cooling conditions by initially drilling radial channels every 30 degrees, then every 15 degrees into the shorting plate. The modified prototype performed well up to 9 MV/m in cw mode. This paper reports about our experiences with the further modified coaxial coupler and about test results in cw and low duty cycle pulsed mode, similar to the TESLA/ILC operation conditions.« less
Connectivity in a Karst System Using Electrical Resistivity Tomography and Network Theory.
Gómez-Nicolás, Mariana; Rebolledo-Vieyra, Mario; Canto-Lugo, Efrain; Huerta-Quintanilla, Rodrigo; Ochoa-Sandoval, Pablo
2017-11-29
The Ring of Cenotes (RC) is an alignment of numerous cenotes (sinkholes) in a semicircular form (with a radius of 100 km) located in northwestern Yucatán, México. The formation roughly coincides with a concentric ring that corresponds to a buried structure, which has been identified as the product of a meteor impact, known as the Chicxulub crater. Secondary permeability generated by the fracturing and faulting of the sedimentary sequence in the Chicxulub crater has favored the karstification process and therefore the development of underground rivers that transport water from the mainland to the sea. This study implements the network theory to study the hydrological connectivity between a group of 11 cenotes within the RC. Eight electrical resistivity tomography transects were used as an empirical basis. Each transect was acquired directly in the field using the SuperSting R1/IP equipment with a dipole-dipole configuration. An adapted version of the reliability algorithm for communication networks was used as a theoretical model. We found evidence of the existence of water cavities in the study area. We made a network from the data and assigned connection probabilities among cenotes as a function of the separation length and the number of water cavities, as well as their size. © 2017, National Ground Water Association.
Orienting members in a preselected rotary alignment
Williams, Ray E.
1987-01-01
An apparatus for orienting members and for maintaining their rotary alignment during orienting members. The apparatus comprises first and second cylindrical elements, a rotation prevention element, a collar and a retainer. Each element has an outside wall, and first and second ends, each end having an outside edge. The first element has portions defining a first plurality of notches located at the outside edge of its first end. An external threaded portion is on the outside wall of the first element and next to the first plurality of notches. The second element has portions defining a second plurality of notches located at the outside edge of its first end. The first plurality has a different number than the second plurality. The first ends of the first and second tubes have substantially the same outside diameter and are abutted during connection so that a cavity is formed whenever first and second tube notches substantially overlap. A rotation prevention element is placed in the cavity to prevent rotation of the first and second elements. A collar with an internal threaded portion is slidably disposed about the second element. The internal threaded portion engages the external threaded portion of the first element to connect the elements. A lip connected to the collar prevents separation of the collar from the second element.
Assessment of thermal loads in the CERN SPS crab cavities cryomodule1
NASA Astrophysics Data System (ADS)
Carra, F.; Apeland, J.; Calaga, R.; Capatina, O.; Capelli, T.; Verdú-Andrés, S.; Zanoni, C.
2017-07-01
As a part of the HL-LHC upgrade, a cryomodule is designed to host two crab cavities for a first test with protons in the SPS machine. The evaluation of the cryomodule heat loads is essential to dimension the cryogenic infrastructure of the system. The current design features two cryogenic circuits. The first circuit adopts superfluid helium at 2 K to maintain the cavities in the superconducting state. The second circuit, based on helium gas at a temperature between 50 K and 70 K, is connected to the thermal screen, also serving as heat intercept for all the interfaces between the cold mass and the external environment. An overview of the heat loads to both circuits, and the combined numerical and analytical estimations, is presented. The heat load of each element is detailed for the static and dynamic scenarios, with considerations on the design choices for the thermal optimization of the most critical components.
Apparatus for detecting alpha radiation in difficult access areas
Steadman, Peter; MacArthur, Duncan W.
1997-09-02
An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure.
Wind turbine/generator set and method of making same
Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.
2013-06-04
A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.
Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.
2012-11-13
A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.
Wind turbine having a direct-drive drivetrain
Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.
2011-02-22
A wind turbine comprising an electrical generator that includes a rotor assembly. A wind rotor that includes a wind rotor hub is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle via a bearing assembly. The wind rotor hub includes an opening having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity inside the wind rotor hub. The spindle is attached to a turret supported by a tower. Each of the spindle, turret and tower has an interior cavity that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.
Apparatus and methods for splicing conduits and hoses subsea
DOE Office of Scientific and Technical Information (OSTI.GOV)
Slocum, Alexander Henry; Gutierrez, Luis Javier
A hose connection system comprises a body including an internal cavity and a port in fluid communication with a portion of the internal cavity. In addition, the system comprises a hose end fitting positioned in the cavity. The hose end fitting includes an inner tubular member and an outer tubular member concentrically disposed about the inner tubular member. The outer tubular member includes a plurality of circumferentially spaced axial slits. Further, the system comprises a plurality of wedge members arranged circumferentially about the outer tubular member. Still further, the system comprises an annular piston movably disposed within the internal cavitymore » of the body. An end of the piston has an inner frustoconical surface that slidingly engages the plurality of wedge members. The piston is configured to move axially through the body and compress the wedge members and the outer tubular member radially inward.« less
A numerical study of active structural acoustic control in a stiffened, double wall cylinder
NASA Technical Reports Server (NTRS)
Grosveld, Ferdinand W.; Coats, T. J.; Lester, H. C.; Silcox, R. J.
1994-01-01
It is demonstrated that active structural acoustic control of complex structural/acoustic coupling can be numerically modeled using finite element and boundary element techniques in conjunction with an optimization procedure to calculate control force amplitudes. Appreciable noise reduction is obtained when the structure is excited at a structural resonance of the outer shell or an acoustic resonance of the inner cavity. Adding ring stiffeners as a connection between the inner and outer shells provides an additional structural transmission path to the interior cavity and coupled the modal behavior of the inner and outer shells. For the case of excitation at the structural resonance of the unstiffened outer shell, adding the stiffeners raises the structural resonance frequencies. The effectiveness of the control forces is reduced due to the off resonance structural response. For excitation at an acoustic cavity resonance, the controller effectiveness is enhanced.
Finocchiaro, L M E; Glikin, G C
2008-02-01
We evaluated the safety, efficacy and anti-tumor effects of a surgery adjuvant treatment on canine patients with malignant melanoma. This approach combined suicide gene therapy with a subcutaneous vaccine composed by formolized tumor cells and irradiated xenogeneic cells producing human interleukin-2 and granulocyte-macrophage colony-stimulating factor. The post-surgical margin of the cavity was infiltrated with lipid-complexed thymidine kinase suicide gene coadministrated with ganciclovir. Toxicity was minimal or absent in all patients. With respect to surgery-treated controls (SC), this combined treatment (CT) significantly increased the fraction of patients local disease-free from 6 to 58% and distant metastases-free from 43 to 78% (Fisher's Exact test). In addition, CT significantly improved both SC overall 78 (23-540) and metastasis-free survival 112 (0-467) days to more than 1312 days (respective ranges: 43-1312 and 0-1312) (Kaplan-Meier analysis). In those patients subjected to partial surgery or presenting local recurrence, the efficacy of CT was verified by a 49% of objective responses that averaged 85% of tumor mass loss, while 22% displayed tumor progression as 94% of SC did. Therefore, surgery adjuvant CT controlled tumor growth, delaying or preventing post-surgical recurrence and distant metastasis, significantly extending survival and recovering the quality of life.
Altered Connectivity and Action Model Formation in Autism Is Autism
Mostofsky, Stewart H.; Ewen, Joshua B.
2014-01-01
Internal action models refer to sensory-motor programs that form the brain basis for a wide range of skilled behavior and for understanding others’ actions. Development of these action models, particularly those reliant on visual cues from the external world, depends on connectivity between distant brain regions. Studies of children with autism reveal anomalous patterns of motor learning and impaired execution of skilled motor gestures. These findings robustly correlate with measures of social and communicative function, suggesting that anomalous action model formation may contribute to impaired development of social and communicative (as well as motor) capacity in autism. Examination of the pattern of behavioral findings, as well as convergent data from neuroimaging techniques, further suggests that autism-associated action model formation may be related to abnormalities in neural connectivity, particularly decreased function of long-range connections. This line of study can lead to important advances in understanding the neural basis of autism and, more critically, can be used to guide effective therapies targeted at improving social, communicative, and motor function. PMID:21467306
Zou, Ling; Guo, Qian; Xu, Yi; Yang, Biao; Jiao, Zhuqing; Xiang, Jianbo
2016-04-29
Functional magnetic resonance imaging (fMRI) is an important tool in neuroscience for assessing connectivity and interactions between distant areas of the brain. To find and characterize the coherent patterns of brain activity as a means of identifying brain systems for the cognitive reappraisal of the emotion task, both density-based k-means clustering and independent component analysis (ICA) methods can be applied to characterize the interactions between brain regions involved in cognitive reappraisal of emotion. Our results reveal that compared with the ICA method, the density-based k-means clustering method provides a higher sensitivity of polymerization. In addition, it is more sensitive to those relatively weak functional connection regions. Thus, the study concludes that in the process of receiving emotional stimuli, the relatively obvious activation areas are mainly distributed in the frontal lobe, cingulum and near the hypothalamus. Furthermore, density-based k-means clustering method creates a more reliable method for follow-up studies of brain functional connectivity.
NASA Astrophysics Data System (ADS)
Dalesandro, Andrew A.; Theilacker, Jay; Van Sciver, Steven
2012-06-01
Safe operation of superconducting radio frequency (SRF) cavities require design consideration of a sudden catastrophic loss of vacuum (SCLV) adjacent with liquid helium (LHe) vessels and subsequent dangers. An experiment is discussed to test the longitudinal effects of SCLV along the beam line of a string of scaled SRF cavities. Each scaled cavity includes one segment of beam tube within a LHe vessel containing 2 K saturated LHe, and a riser pipe connecting the LHe vessel to a common gas header. At the beam tube inlet is a fast acting solenoid valve to simulate SCLV and a high/low range orifice plate flow-meter to measure air influx to the cavity. The gas header exit also has an orifice plate flow-meter to measure helium venting the system at the relief pressure of 0.4 MPa. Each cavity is instrumented with Validyne pressure transducers and Cernox thermometers. The purpose of this experiment is to quantify the time required to spoil the beam vacuum and the effects of transient heat and mass transfer on the helium system. Heat transfer data is expected to reveal a longitudinal effect due to the geometry of the experiment. Details of the experimental design criteria and objectives are presented.
A device for microwave sintering large ceramic articles
Kimrey, H.D. Jr.
1987-07-24
A microwave sintering system is provided for uniform sintering of large and/or irregular shapes ceramic articles at microwave frequencies of at least 28 GHz in the hundreds of kilowatts power range in an untuned cavity. A 28 GHz, 200 kw gyrotron with variable power output is used as the microwave source connected to an untuned microwave cavity formed of an electrically conductive housing. The part to be sintered is placed in the cavity and supported on a removable high temperature table in a central location within the cavity. The part is surrounded by a microwave transparent bulk insulating material to reduce thermal heat loss at the part surfaces and maintain more uniform temperature. The cavity may be operated at a high vacuum to aid in preventing arcing. The system allows controlled increased heating rates of greater than 200/degree/C/min to provide rapid heating of a ceramic part to a selected sintering temperature where it is maintained by regulating the microwave power applied to the part. As a result of rapid heating, the extent on non-isothermal processes such as segregation of impurities to the grain boundaries are minimized and exaggerated grain growth is reduced, thereby strengthening the mechanical properties of the ceramic part being sintered. 1 fig.
Proof-of-principle Experiment of a Ferroelectric Tuner for the 1.3 GHz Cavity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi,E.M.; Hahn, H.; Shchelkunov, S. V.
2009-01-01
A novel tuner has been developed by the Omega-P company to achieve fast control of the accelerator RF cavity frequency. The tuner is based on the ferroelectric property which has a variable dielectric constant as function of applied voltage. Tests using a Brookhaven National Laboratory (BNL) 1.3 GHz electron gun cavity have been carried out for a proof-of-principle experiment of the ferroelectric tuner. Two different methods were used to determine the frequency change achieved with the ferroelectric tuner (FT). The first method is based on a S11 measurement at the tuner port to find the reactive impedance change when themore » voltage is applied. The reactive impedance change then is used to estimate the cavity frequency shift. The second method is a direct S21 measurement of the frequency shift in the cavity with the tuner connected. The estimated frequency change from the reactive impedance measurement due to 5 kV is in the range between 3.2 kHz and 14 kHz, while 9 kHz is the result from the direct measurement. The two methods are in reasonable agreement. The detail description of the experiment and the analysis are discussed in the paper.« less
On the respiratory flow in the cuttlefish sepia officinalis.
Bone, Q; Brown, E; Travers, G
1994-09-01
The respiratory flow of water over the gills of the cuttlefish Sepia officinalis at rest is produced by the alternate activity of the radial muscles of the mantle and the musculature of the collar flaps; mantle circular muscle fibres are not involved. Inspiration takes place as the radial fibres contract, thinning the mantle and expanding the mantle cavity. The rise in mantle cavity pressure (up to 0.15 kPa), expelling water via the siphon during expiration, is brought about by inward movement of the collar flaps and (probably) mainly by elastic recoil of the mantle connective tissue network 'wound up' by radial fibre contraction during inspiration. Sepia also shows a second respiratory pattern, in which mantle cavity pressures during expiration are greater (up to 0.25 kPa). Here, the mantle circular fibres are involved, as they are during the large pressure transients (up to 10 kPa) seen during escape jetting. Active contraction of the muscles of the collar flaps is seen in all three patterns of expulsion of water from the mantle cavity, electrical activity increasing with increasing mantle cavity pressures. Respiratory expiration in the resting squid Loligo vulgaris is probably driven as in Sepia, whereas in the resting octopus Eledone cirrhosa, the mantle circular musculature is active during expiration. The significance of these observations is discussed.
Cooling for SC devices of test cryomodule for ADS Injector II at IMP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, L.; Wang, S. Y.; Sun, S.
2014-01-29
The superconducting half-wave resonance cavities connected in series with superconducting solenoids will be applied to the Injector II of the Accelerator Driven Sub-critical System (ADS) to be built at the Modern Physics Institute, China. A test system has been developed for the purpose of performance test of the HWR cavities as well as validating the relevant technique for cooling the cavity and the solenoids together. It mainly comprises a cryogenic valve box (TVB), a test cryomodule (TCM1) and transfer lines. The TCM1 includes one HWR cavity, two superconducting solenoids, one cold BPM and their cooling system. The design of themore » TCM1 cryostat was carried out by the Shanghai Institute of Applied Physics (SINAP), CAS. Both the cavity and the solenoids will work at 4.4 K by bath cooling. The fast cooling down for the cavity from around 100 K to 120 K is required to avoid degrading of the cavity performance. After cool down and before energization, the solenoids should be warmed up to above 10 K and re-cooled down for the purpose of degaussing. The TCM1 can not only be cooled by using the dewar-filling system, but also operated by the refrigerator system. For the purpose of reducing the heat loads to the cold mass at 4 K from room temperature, thermal radiation shields cooled by liquid nitrogen flowing in tubing were employed. This paper presents the design details of cooling circuits and thermal shields of the TCM1 as well as related calculations and analyses.« less
Cooling for SC devices of test cryomodule for ADS Injector II at IMP
NASA Astrophysics Data System (ADS)
Wang, L.; Wang, S. Y.; Sun, S.; Guo, X. L.; Wang, S. H.; Liu, Y. Y.
2014-01-01
The superconducting half-wave resonance cavities connected in series with superconducting solenoids will be applied to the Injector II of the Accelerator Driven Sub-critical System (ADS) to be built at the Modern Physics Institute, China. A test system has been developed for the purpose of performance test of the HWR cavities as well as validating the relevant technique for cooling the cavity and the solenoids together. It mainly comprises a cryogenic valve box (TVB), a test cryomodule (TCM1) and transfer lines. The TCM1 includes one HWR cavity, two superconducting solenoids, one cold BPM and their cooling system. The design of the TCM1 cryostat was carried out by the Shanghai Institute of Applied Physics (SINAP), CAS. Both the cavity and the solenoids will work at 4.4 K by bath cooling. The fast cooling down for the cavity from around 100 K to 120 K is required to avoid degrading of the cavity performance. After cool down and before energization, the solenoids should be warmed up to above 10 K and re-cooled down for the purpose of degaussing. The TCM1 can not only be cooled by using the dewar-filling system, but also operated by the refrigerator system. For the purpose of reducing the heat loads to the cold mass at 4 K from room temperature, thermal radiation shields cooled by liquid nitrogen flowing in tubing were employed. This paper presents the design details of cooling circuits and thermal shields of the TCM1 as well as related calculations and analyses.
A universal quantum module for quantum communication, computation, and metrology
NASA Astrophysics Data System (ADS)
Hanks, Michael; Lo Piparo, Nicolò; Trupke, Michael; Schmiedmayer, Jorg; Munro, William J.; Nemoto, Kae
2017-08-01
In this work, we describe a simple module that could be ubiquitous for quantum information based applications. The basic modules comprises a single NV- center in diamond embedded in an optical cavity, where the cavity mediates interactions between photons and the electron spin (enabling entanglement distribution and efficient readout), while the nuclear spins constitutes a long-lived quantum memories capable of storing and processing quantum information. We discuss how a network of connected modules can be used for distributed metrology, communication and computation applications. Finally, we investigate the possible use of alternative diamond centers (SiV/GeV) within the module and illustrate potential advantages.
Structure and symmetry in coherent perfect polarization rotation
NASA Astrophysics Data System (ADS)
Crescimanno, Michael; Zhou, Chuanhong; Andrews, James H.; Baker, Michael A.
2015-01-01
Theoretical investigations of different routes to coherent perfect polarization rotation illustrate its phenomenological connection with coherent perfect absorption. Our study of systems with broken parity, layering, combined Faraday rotation and optical activity, or a rotator-loaded optical cavity highlights their similarity and suggests alternate approaches to improving and miniaturizing optical devices.
Beaming into the News: A System for and Case Study of Tele-Immersive Journalism.
Kishore, Sameer; Navarro, Xavi; Dominguez, Eva; de la Pena, Nonny; Slater, Mel
2016-05-25
We show how a combination of virtual reality and robotics can be used to beam a physical representation of a person to a distant location, and describe an application of this system in the context of journalism. Full body motion capture data of a person is streamed and mapped in real time, onto the limbs of a humanoid robot present at the remote location. A pair of cameras in the robot's 'eyes' stream stereoscopic video back to the HMD worn by the visitor, and a two-way audio connection allows the visitor to talk to people in the remote destination. By fusing the multisensory data of the visitor with the robot, the visitor's 'consciousness' is transformed to the robot's body. This system was used by a journalist to interview a neuroscientist and a chef 900 miles distant, about food for the brain, resulting in an article published in the popular press.
Beaming into the News: A System for and Case Study of Tele-Immersive Journalism.
Kishore, Sameer; Navarro, Xavi; Dominguez, Eva; De La Pena, Nonny; Slater, Mel
2018-03-01
We show how a combination of virtual reality and robotics can be used to beam a physical representation of a person to a distant location, and describe an application of this system in the context of journalism. Full body motion capture data of a person is streamed and mapped in real time, onto the limbs of a humanoid robot present at the remote location. A pair of cameras in the robots eyes stream stereoscopic video back to the HMD worn by the visitor, and a two-way audio connection allows the visitor to talk to people in the remote destination. By fusing the multisensory data of the visitor with the robot, the visitors consciousness is transformed to the robots body. This system was used by a journalist to interview a neuroscientist and a chef 900 miles distant, about food for the brain, resulting in an article published in the popular press.
Neuroeffector connections of giant multimodal neurons in the African snail Achatina fulica.
Bugai, V V; Zhuravlev, V L; Safonova, T A
2005-07-01
A new method of making preparations was used to analyse the neuroeffector connections of the paired giant neurons of the African snail Achatina fulica. These neurons were found to induce postsynaptic potentials in the muscles of the mantle, heart, the wall of the pulmonary cavity, and the muscular elements of the renal complex, the pericardium, the sexual apparatus, the walls of the cerebral arteries, the filaments of the columellar muscles, the wall of the abdomen, and the tentacle retractor muscles. Rhythmic neuron activity led to the development of marked facilitation and long-term potentiation of synaptic potentials. The possible significance of the multiple neuroeffector connections of giant neurons is discussed.
Quiet planting in the locked constraints satisfaction problems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zdeborova, Lenka; Krzakala, Florent
2009-01-01
We study the planted ensemble of locked constraint satisfaction problems. We describe the connection between the random and planted ensembles. The use of the cavity method is combined with arguments from reconstruction on trees and first and second moment considerations; in particular the connection with the reconstruction on trees appears to be crucial. Our main result is the location of the hard region in the planted ensemble, thus providing hard satisfiable benchmarks. In a part of that hard region instances have with high probability a single satisfying assignment.
Waves and rays in plano-concave laser cavities: I. Geometric modes in the paraxial approximation
NASA Astrophysics Data System (ADS)
Barré, N.; Romanelli, M.; Lebental, M.; Brunel, M.
2017-05-01
Eigenmodes of laser cavities are studied theoretically and experimentally in two companion papers, with the aim of making connections between undulatory and geometric properties of light. In this first paper, we focus on macroscopic open-cavity lasers with localized gain. The model is based on the wave equation in the paraxial approximation; experiments are conducted with a simple diode-pumped Nd:YAG laser with a variable cavity length. After recalling fundamentals of laser beam optics, we consider plano-concave cavities with on-axis or off-axis pumping, with emphasis put on degenerate cavity lengths, where modes of different order resonate at the same frequency, and combine to form surprising transverse beam profiles. Degeneracy leads to the oscillation of so-called geometric modes whose properties can be understood, to a certain extent, also within a ray optics picture. We first provide a heuristic description of these modes, based on geometric reasoning, and then show more rigorously how to derive them analytically by building wave superpositions, within the framework of paraxial wave optics. The numerical methods, based on the Fox-Li approach, are described in detail. The experimental setup, including the imaging system, is also detailed and relatively simple to reproduce. The aim is to facilitate implementation of both the numerics and of the experiments, and to show that one can have access not only to the common higher-order modes but also to more exotic patterns.
Optimal directional volatile transport in retronasal olfaction
Ni, Rui; Michalski, Mark H.; Brown, Elliott; Doan, Ngoc; Zinter, Joseph; Ouellette, Nicholas T.; Shepherd, Gordon M.
2015-01-01
The ability of humans to distinguish the delicate differences in food flavors depends mostly on retronasal smell, in which food volatiles entrained into the airway at the back of the oral cavity are transported by exhaled air through the nasal cavity to stimulate the olfactory receptor neurons. Little is known whether food volatiles are preferentially carried by retronasal flow toward the nasal cavity rather than by orthonasal flow into the lung. To study the differences between retronasal and orthonasal flow, we obtained computed tomography (CT) images of the orthonasal airway from a healthy human subject, printed an experimental model using a 3D printer, and analyzed the flow field inside the airway. The results show that, during inhalation, the anatomical structure of the oropharynx creates an air curtain outside a virtual cavity connecting the oropharynx and the back of the mouth, which prevents food volatiles from being transported into the main stream toward the lung. In contrast, during exhalation, the flow preferentially sweeps through this virtual cavity and effectively enhances the entrainment of food volatiles into the main retronasal flow. This asymmetrical transport efficiency is also found to have a nonmonotonic Reynolds number dependence: The asymmetry peaks at a range of an intermediate Reynolds number close to 800, because the air curtain effect during inhalation becomes strongest in this range. This study provides the first experimental evidence, to our knowledge, for adaptations of the geometry of the human oropharynx for efficient transport of food volatiles toward the olfactory receptors in the nasal cavity. PMID:26553982
DOE Office of Scientific and Technical Information (OSTI.GOV)
Atalar, Banu; Modlin, Leslie A.; Choi, Clara Y.H.
Purpose: We sought to determine the risk of leptomeningeal disease (LMD) in patients treated with stereotactic radiosurgery (SRS) targeting the postsurgical resection cavity of a brain metastasis, deferring whole-brain radiation therapy (WBRT) in all patients. Methods and Materials: We retrospectively reviewed 175 brain metastasis resection cavities in 165 patients treated from 1998 to 2011 with postoperative SRS. The cumulative incidence rates, with death as a competing risk, of LMD, local failure (LF), and distant brain parenchymal failure (DF) were estimated. Variables associated with LMD were evaluated, including LF, DF, posterior fossa location, resection type (en-bloc vs piecemeal or unknown), andmore » histology (lung, colon, breast, melanoma, gynecologic, other). Results: With a median follow-up of 12 months (range, 1-157 months), median overall survival was 17 months. Twenty-one of 165 patients (13%) developed LMD at a median of 5 months (range, 2-33 months) following SRS. The 1-year cumulative incidence rates, with death as a competing risk, were 10% (95% confidence interval [CI], 6%-15%) for developing LF, 54% (95% CI, 46%-61%) for DF, and 11% (95% CI, 7%-17%) for LMD. On univariate analysis, only breast cancer histology (hazard ratio, 2.96) was associated with an increased risk of LMD. The 1-year cumulative incidence of LMD was 24% (95% CI, 9%-41%) for breast cancer compared to 9% (95% CI, 5%-14%) for non-breast histology (P=.004). Conclusions: In patients treated with SRS targeting the postoperative cavity following resection, those with breast cancer histology were at higher risk of LMD. It is unknown whether the inclusion of whole-brain irradiation or novel strategies such as preresection SRS would improve this risk or if the rate of LMD is inherently higher with breast histology.« less
Roesch-Ely, Mariana; Schnölzer, Martina; Nees, Matthias; Plinkert, Peter K; Bosch, Franz X
2010-01-01
We reasoned that micro-dissection of tumour cells for protein expression studies should be omitted since tumour-stroma interactions are an important part of the biology of solid tumours. To study such interactions in head and neck squamous cell carcinoma (HNSCC) development, we generated reference protein spectra for normal squamous epithelium and connective tissue by SELDI-TOF-MS. Calgranulins A and B, Annexin1 and Histone H4 were found to be strongly enriched in the epithelium. The alpha-defensins 1-3 and the haemoglobin subunits were identified in the connective tissue. Tumour-distant epithelia, representing early pre-malignant lesions, showed up-regulated expression of the stromal alpha-defensins, whereas the epithelial Annexin 1 was down-regulated. Thus, tumour microenvironment interactions occur very early in the carcinogenic process. These data demonstrate that omitting micro-dissection is actually beneficial for studying changes in protein expression during development and progression of solid tumours.
Development of the brain's functional network architecture.
Vogel, Alecia C; Power, Jonathan D; Petersen, Steven E; Schlaggar, Bradley L
2010-12-01
A full understanding of the development of the brain's functional network architecture requires not only an understanding of developmental changes in neural processing in individual brain regions but also an understanding of changes in inter-regional interactions. Resting state functional connectivity MRI (rs-fcMRI) is increasingly being used to study functional interactions between brain regions in both adults and children. We briefly review methods used to study functional interactions and networks with rs-fcMRI and how these methods have been used to define developmental changes in network functional connectivity. The developmental rs-fcMRI studies to date have found two general properties. First, regional interactions change from being predominately anatomically local in children to interactions spanning longer cortical distances in young adults. Second, this developmental change in functional connectivity occurs, in general, via mechanisms of segregation of local regions and integration of distant regions into disparate subnetworks.
Development of the Brain's Functional Network Architecture
Power, Jonathan D.; Petersen, Steven E.; Schlaggar, Bradley L.
2013-01-01
A full understanding of the development of the brain's functional network architecture requires not only an understanding of developmental changes in neural processing in individual brain regions but also an understanding of changes in inter-regional interactions. Resting state functional connectivity MRI (rs-fcMRI) is increasingly being used to study functional interactions between brain regions in both adults and children. We briefly review methods used to study functional interactions and networks with rs-fcMRI and how these methods have been used to define developmental changes in network functional connectivity. The developmental rs-fcMRI studies to date have found two general properties. First, regional interactions change from being predominately anatomically local in children to interactions spanning longer cortical distances in young adults. Second, this developmental change in functional connectivity occurs, in general, via mechanisms of segregation of local regions and integration of distant regions into disparate subnetworks. PMID:20976563
Synchronization and communication of cooperative sensors.
Chételat, Olivier; Rapin, Michael; Meier, Christophe; Bischof, André; Augustyniak, Marcin K
2015-01-01
Cooperative sensors are an emerging technology consisting of autonomous sensor units working in concert to measure physiological signals requiring distant sensing points, such as biopotential (e.g., ECG) or bioimpedance (e.g., EIT). Their advantage with respect to the state-of-the-art technology is that they do not require shielded and even insulated cables to measure best quality biopotential or bioimpedance signals. Moreover, as all sensors are simply connected to a single electrical connection (which can be for instance a conductive vest) there is no connecting limitation to the miniaturization of the system or to its extension to large numbers of sensors. This results in an increase of wearability and comfort, as well as in a decrease of costs and integration challenges. However, cooperative sensors must communicate to be synchronized and to centralize the data. This paper presents possible communication strategies and focuses on the implementation of one of them that is particularly well suited for biopotential and bioimpedance measurements.
Inflammatory breast metastases of ovarian cancer: a case report.
Kayikçioğlu, F; Boran, N; Ayhan, A; Güler, N
2001-12-01
Metastasis to the breast from extramammary malignancies is rare. A 35-year-old woman presented with bilaterally inflammatory breast involvement, 2 years after the diagnosis of stage IIIC epithelial ovarian cancer. Neoplastic tissue was immunohistochemically positive using antibodies against OC125 and negative for gross cystic disease fluid protein-15 (BRST-2) and estrogen receptor in biopsy material in the breast. Combination chemotherapy consisting of paclitaxel, cisplatin, and anthracycline was started. She died 18 months after the breast metastasis. Ovarian carcinoma usually presents with signs and symptoms related to the tumor burden within the abdominal cavity. The finding of isolated, distant metastases such as breast involvement without intraabdominal disease is extremely rare. Determining the origin of the primary tumor is important in directing the actual therapy. (c)2001 Elsevier Science.
Malignant ameloblastic fibro-odontoma in a dog.
Ueki, H; Sumi, A; Takaishi, H; Ito, H; Oyamada, T; Yoshikawa, H
2004-03-01
An 11-year-old male Collie was presented with a swelling of the face caused by tumor masses arising from the gingiva. Postmortem examination revealed metastases to the lymph nodes, lung, liver, and orbital cavity. Histologically, the tumor represented a combination of fibrosarcomatous proliferation, pulpal mesenchyme, and undifferentiated odontogenic epithelium, with a follicular or plexiform growth pattern. In addition, the follicular areas of the tumor showed a biphasic character, and there were numerous apoptotic cells in plexiform areas. Furthermore, acidophilic material resembling dysplastic dentine or enamel matrix was observed in the metastatic lesion in the lung. Based on the histological characters, the present case was diagnosed as malignant ameloblastic fibro-odontoma. This study is the first known description of a possible malignant ameloblastic fibro-odontoma in a dog with metastasis to distant organs.
Corona, S A; Borsatto, M; Dibb, R G; Ramos, R P; Brugnera, A; Pécora, J D
2001-01-01
This in vitro study compared the microleakage of Class V resin composite restorations placed in cavities prepared with a high-speed dental bur, air-abrasion or Er:YAG laser. Twenty sound extracted human third molars were selected and randomly assigned to four equal Groups (n=10): Group I, cavities were cut by dental drill at high-speed; Group II, aluminum oxide air-abrasion was used for cavity preparation, and in Groups III and IV, cavities were prepared by Er:YAG laser. Following cavity preparation, Groups I and II were acid-etched, Group III was treated only by Er:YAG laser and Group IV was conditioned by Er:YAG laser followed by acid-etching. Cavities were restored (Single Bond + Z-100) and the teeth stored for seven days in distilled water. Then, the restorations were polished and the specimens thermocycled, immersed in a 0.2% Rhodamine solution, sectioned and analyzed for leakage at the occlusal (enamel) and cervical (dentin/cementum) interfaces using an optical microscope connected to a video camera. The images were digitized and software was utilized for microleakage assessment. Upon analyzing the results, statistically significant differences (p<0.01) between the occlusal and cervical regions for all groups was observed, and, as a rule, there was better marginal sealing at the enamel margins. The highest degree of infiltration was observed for cavities prepared and treated exclusively by Er:YAG (Group III). The other experimental groups showed statistical similarities in the amount of marginal leakage at the enamel margins. However, at the cervical margins, there was a significant difference (p<0.05) between Group I and the remaining groups. None of the techniques completely eliminated marginal microleakage at the dentin/ cementum margins.
Microwave switching power divider. [antenna feeds
NASA Technical Reports Server (NTRS)
Stockton, R. J.; Johnson, R. W. (Inventor)
1981-01-01
A pair of parallel, spaced-apart circular ground planes define a microwave cavity with multi-port microwave power distributing switching circuitry formed on opposite sides of a thin circular dielectric substrate disposed between the ground planes. The power distributing circuitry includes a conductive disk located at the center of the substrate and connected to a source of microwave energy. A high speed, low insertion loss switching diode and a dc blocking capacitor are connected in series between the outer end of a transmission line and an output port. A high impedance, microwave blocking dc bias choke is connected between each switching diode and a source of switching current. The switching source forward biases the diodes to couple microwave energy from the conductive disk to selected output ports and, to associated antenna elements connected to the output ports to form a synthesized antenna pattern.
NASA Astrophysics Data System (ADS)
Lu, En; Ran, Zengling; Peng, Fei; Liu, Zhiwei; Xu, Fuguo
2012-03-01
Subcarrier technology and dual-wavelength demodulation method are combined for tracking the cavity length variation of a micro fiber-optic Fabry-Perot (F-P). Compared with conventional dual-wavelength demodulation method, two operation wavelengths for demodulation are modulated with two different carrier frequencies, respectively, and then injected into optical link connected with the F-P cavity. Light power reflected for the two wavelengths is obtained by interrogating the powers of Fast Fourier Transform (FFT) spectrum at their carrier frequencies. Because the light at the two wavelengths experiences the same optical and electrical routes, measurement deviation resulting from the drift of optical and electrical links can be entirely eliminated.
NASA Astrophysics Data System (ADS)
Ran, Zengling; Rao, Yunjiang; Liu, Zhiwei; Xu, Fuguo
2011-05-01
Subcarrier technology and dual-wavelength demodulation method are combined for tracking the cavity length variation of a micro fiber-optic fabry-periot (F-P). Compared with conventional dual-wavelength demodulation method, two operation wavelengths for demodulation are modulated with two different carrier frequencies, respectively, and then injected into optical link connected with the F-P cavity. Light power reflected for the two wavelengths is obtained by interrogating the powers of Fast Fourier Transform (FFT) spectrum at their carrier frequencies. Because the light at the two wavelengths experiences the same optical and electrical routes, measurement deviation resulting from the drift of optical and electrical links can be entirely eliminated.
Pathways of abdominal tumour spread: the role of the subperitoneal space
Newmark, Geraldine M.; Thakrar, Kiran H.; Mehta, Uday K.; Berlin, Jonathan W.
2009-01-01
Abstract The subperitoneal space is a large, unifying, anatomically continuous potential space that connects the peritoneal cavity with the retroperitoneum. This space is formed by the subserosal areolar tissue that lines the inner surfaces of the peritoneum and the musculature of the abdomen and pelvis. It contains the branches of the vascular, lymphatic, and nervous systems that supply the viscera. The subperitoneal space extends into the peritoneal cavity and is invested between the layers of the mesenteries and ligaments that support and interconnect the abdominal and pelvic organs. As such, it provides one large continuous space in which infectious, neoplastic, inflammatory, and hemorrhagic disease may spread in many directions. PMID:20080454
A population-based analysis of Head and Neck hemangiopericytoma.
Shaigany, Kevin; Fang, Christina H; Patel, Tapan D; Park, Richard Chan; Baredes, Soly; Eloy, Jean Anderson
2016-03-01
Hemangiopericytomas (HPC) are tumors that arise from pericytes. Hemangiopericytomas of the head and neck are rare and occur both extracranially and intracranially. This study analyzes the demographic, clinicopathologic, treatment modalities, and survival characteristics of extracranial head and neck hemangiopericytomas (HN-HPC) and compares them to HPCs at other body sites (Other-HPC). The Surveillance, Epidemiology, and End Results (SEER) database (1973-2012) was queried for HN-HPC (121 cases) and Other-HPC (510 cases). Data were analyzed comparatively with respect to various demographic and clinicopathologic factors. Disease-specific survival (DSS) was analyzed using the Kaplan-Meier model. There was no significant difference in age at time of diagnosis between HN-HPC and Other-HPC. Head and neck HPC was most commonly located in the connective and soft tissue (18.4%), followed by the nasal cavity and paranasal sinuses (8.5%). Head and neck HPCs were smaller than Other-HPC (P < 0.0001) and more likely to be a lower histologic grade (P < 0.0097). The primary treatment modality for HN-HPC was surgery alone, used in 55.8% of cases. The 5-, 10-, and 20-year DSS for HN-HPC were 84.0%, 79.4%, and 69.4%, respectfully. Higher histologic grade and the presence of distant metastases were poor prognostic factors for HN-HPC. Head and neck HPCs are rare tumors. This study represents the largest series of HN-HPCs to date. Surgery alone is the primary treatment modality for HN-HPC, with a favorable prognosis. Adjuvant radiotherapy does not appear to confer a survival benefit for any body site. 4. Laryngoscope, 126:643-650, 2016. © 2015 The American Laryngological, Rhinological and Otological Society, Inc.
Design and research of RF system for 10 MeV compact cyclotron
NASA Astrophysics Data System (ADS)
Li, Dong; Hu, TongNing; Liu, KaiFeng; Yang, Jun
2011-12-01
A 10 MeV compact cyclotron (CYCHU-10) has been developing in Huazhong University of Science and Technology (HUST). The RF system includes a 10 kW RF power generator and a resonance cavity. There is no automatic frequency tuning equipment in the cavity due to space limitations, so the generator must search and track the cavity resonant frequency. AD9850 synthesizer is used to generate RF signal in the experimental prototype, and a fine sinusoidal waveform around 99 MHz is obtained with the method of picking up a special aliased signal from the synthesizer's output, and the output power level can be set by regulating the resistor connected to the Pin ` R set'. The final stage amplifier based on tetrode operates in the grounded cathode configuration, and the schematic of the tetrode circuit is illustrated. The method of searching the resonant frequency is discussed in detail. For the sake of a compact and robust structure, the resonance cavity will adopt non-uniform characteristic impedance coaxial structure, and the magnet surface electroplated with copper will be used as dummy Dees. The precise shapes and dimensions of the cavity are designed and simulation results are carried out in this paper. The distributions of electromagnetic field are illustrated by means of numerical calculation analysis, and the wooden model test is preformed as well.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Casassus, S.; Marino, S.; Pérez, S.
2015-10-01
The finding of residual gas in the large central cavity of the HD 142527 disk motivates questions regarding the origin of its non-Keplerian kinematics and possible connections with planet formation. We aim to understand the physical structure that underlies the intra-cavity gaseous flows, guided by new molecular-line data in CO(6–5) with unprecedented angular resolutions. Given the warped structure inferred from the identification of scattered-light shadows cast on the outer disk, the kinematics are consistent, to first order, with axisymmetric accretion onto the inner disk occurring at all azimuths. A steady-state accretion profile, fixed at the stellar accretion rate, explains themore » depth of the cavity as traced in CO isotopologues. The abrupt warp and evidence for near free-fall radial flows in HD 142527 resemble theoretical models for disk tearing, which could be driven by the reported low-mass companion, whose orbit may be contained in the plane of the inner disk. The companion’s high inclination with respect to the massive outer disk could drive Kozai oscillations over long timescales; high-eccentricity periods may perhaps account for the large cavity. While shadowing by the tilted disk could imprint an azimuthal modulation in the molecular-line maps, further observations are required to ascertain the significance of azimuthal structure in the density field inside the cavity of HD 142527.« less
Katayama, Yukitoshi; Sakamoto, Tatsuya; Saito, Kazuhiro; Tsuchimochi, Hirotsugu; Kaiya, Hiroyuki; Watanabe, Taro; Pearson, James T; Takei, Yoshio
2018-01-12
Thirst aroused in the forebrain by angiotensin II (AngII) or buccal drying motivates terrestrial vertebrates to search for water, whereas aquatic fish can drink surrounding water only by reflex swallowing generated in the hindbrain. Indeed, AngII induces drinking through the hindbrain even after removal of the whole forebrain in aquatic fish. Here we show that AngII induces thirst also in the amphibious mudskipper goby without direct action on the forebrain, but through buccal drying. Intracerebroventricular injection of AngII motivated mudskippers to move into water and drink as with tetrapods. However, AngII primarily increased immunoreactive c-Fos at the hindbrain swallowing center where AngII receptors were expressed, as in other ray-finned fish, and such direct action on the forebrain was not found. Behavioural analyses showed that loss of buccal water on land by AngII-induced swallowing, by piercing holes in the opercula, or by water-absorptive gel placed in the cavity motivated mudskippers to move to water for refilling. Since sensory detection of water at the bucco-pharyngeal cavity like 'dry mouth' has recently been noted to regulate thirst in mammals, similar mechanisms seem to have evolved in distantly related species in order to solve osmoregulatory problems during terrestrialization.
Patient-specific connectivity pattern of epileptic network in frontal lobe epilepsy
Luo, Cheng; An, Dongmei; Yao, Dezhong; Gotman, Jean
2014-01-01
There is evidence that focal epilepsy may involve the dysfunction of a brain network in addition to the focal region. To delineate the characteristics of this epileptic network, we collected EEG/fMRI data from 23 patients with frontal lobe epilepsy. For each patient, EEG/fMRI analysis was first performed to determine the BOLD response to epileptic spikes. The maximum activation cluster in the frontal lobe was then chosen as the seed to identify the epileptic network in fMRI data. Functional connectivity analysis seeded at the same region was also performed in 63 healthy control subjects. Nine features were used to evaluate the differences of epileptic network patterns in three connection levels between patients and controls. Compared with control subjects, patients showed overall more functional connections between the epileptogenic region and the rest of the brain and higher laterality. However, the significantly increased connections were located in the neighborhood of the seed, but the connections between the seed and remote regions actually decreased. Comparing fMRI runs with interictal epileptic discharges (IEDs) and without IEDs, the patient-specific connectivity pattern was not changed significantly. These findings regarding patient-specific connectivity patterns of epileptic networks in FLE reflect local high connectivity and connections with distant regions differing from those of healthy controls. Moreover, the difference between the two groups in most features was observed in the strictest of the three connection levels. The abnormally high connectivity might reflect a predominant attribute of the epileptic network, which may facilitate propagation of epileptic activity among regions in the network. PMID:24936418
Dawson, Debra Ann; Lam, Jack; Lewis, Lindsay B.; Carbonell, Felix; Mendola, Janine D.
2016-01-01
Abstract Numerous studies have demonstrated functional magnetic resonance imaging (fMRI)-based resting-state functional connectivity (RSFC) between cortical areas. Recent evidence suggests that synchronous fluctuations in blood oxygenation level-dependent fMRI reflect functional organization at a scale finer than that of visual areas. In this study, we investigated whether RSFCs within and between lower visual areas are retinotopically organized and whether retinotopically organized RSFC merely reflects cortical distance. Subjects underwent retinotopic mapping and separately resting-state fMRI. Visual areas V1, V2, and V3, were subdivided into regions of interest (ROIs) according to quadrants and visual field eccentricity. Functional connectivity (FC) was computed based on Pearson's linear correlation (correlation), and Pearson's linear partial correlation (correlation between two time courses after the time courses from all other regions in the network are regressed out). Within a quadrant, within visual areas, all correlation and nearly all partial correlation FC measures showed statistical significance. Consistently in V1, V2, and to a lesser extent in V3, correlation decreased with increasing eccentricity separation. Consistent with previously reported monkey anatomical connectivity, correlation/partial correlation values between regions from adjacent areas (V1-V2 and V2-V3) were higher than those between nonadjacent areas (V1-V3). Within a quadrant, partial correlation showed consistent significance between regions from two different areas with the same or adjacent eccentricities. Pairs of ROIs with similar eccentricity showed higher correlation/partial correlation than pairs distant in eccentricity. Between dorsal and ventral quadrants, partial correlation between common and adjacent eccentricity regions within a visual area showed statistical significance; this extended to more distant eccentricity regions in V1. Within and between quadrants, correlation decreased approximately linearly with increasing distances separating the tested ROIs. Partial correlation showed a more complex dependence on cortical distance: it decreased exponentially with increasing distance within a quadrant, but was best fit by a quadratic function between quadrants. We conclude that RSFCs within and between lower visual areas are retinotopically organized. Correlation-based FC is nonselectively high across lower visual areas, even between regions that do not share direct anatomical connections. The mechanisms likely involve network effects caused by the dense anatomical connectivity within this network and projections from higher visual areas. FC based on partial correlation, which minimizes network effects, follows expectations based on direct anatomical connections in the monkey visual cortex better than correlation. Last, partial correlation-based retinotopically organized RSFC reflects more than cortical distance effects. PMID:26415043
Dawson, Debra Ann; Lam, Jack; Lewis, Lindsay B; Carbonell, Felix; Mendola, Janine D; Shmuel, Amir
2016-02-01
Numerous studies have demonstrated functional magnetic resonance imaging (fMRI)-based resting-state functional connectivity (RSFC) between cortical areas. Recent evidence suggests that synchronous fluctuations in blood oxygenation level-dependent fMRI reflect functional organization at a scale finer than that of visual areas. In this study, we investigated whether RSFCs within and between lower visual areas are retinotopically organized and whether retinotopically organized RSFC merely reflects cortical distance. Subjects underwent retinotopic mapping and separately resting-state fMRI. Visual areas V1, V2, and V3, were subdivided into regions of interest (ROIs) according to quadrants and visual field eccentricity. Functional connectivity (FC) was computed based on Pearson's linear correlation (correlation), and Pearson's linear partial correlation (correlation between two time courses after the time courses from all other regions in the network are regressed out). Within a quadrant, within visual areas, all correlation and nearly all partial correlation FC measures showed statistical significance. Consistently in V1, V2, and to a lesser extent in V3, correlation decreased with increasing eccentricity separation. Consistent with previously reported monkey anatomical connectivity, correlation/partial correlation values between regions from adjacent areas (V1-V2 and V2-V3) were higher than those between nonadjacent areas (V1-V3). Within a quadrant, partial correlation showed consistent significance between regions from two different areas with the same or adjacent eccentricities. Pairs of ROIs with similar eccentricity showed higher correlation/partial correlation than pairs distant in eccentricity. Between dorsal and ventral quadrants, partial correlation between common and adjacent eccentricity regions within a visual area showed statistical significance; this extended to more distant eccentricity regions in V1. Within and between quadrants, correlation decreased approximately linearly with increasing distances separating the tested ROIs. Partial correlation showed a more complex dependence on cortical distance: it decreased exponentially with increasing distance within a quadrant, but was best fit by a quadratic function between quadrants. We conclude that RSFCs within and between lower visual areas are retinotopically organized. Correlation-based FC is nonselectively high across lower visual areas, even between regions that do not share direct anatomical connections. The mechanisms likely involve network effects caused by the dense anatomical connectivity within this network and projections from higher visual areas. FC based on partial correlation, which minimizes network effects, follows expectations based on direct anatomical connections in the monkey visual cortex better than correlation. Last, partial correlation-based retinotopically organized RSFC reflects more than cortical distance effects.
Infrasonic harmonic tremor and degassing bursts from Halema'uma'u Crater, Kilauea Volcano, Hawaii
Fee, David; Garcés, Milton; Patrick, Matt; Chouet, Bernard; Dawson, Phil; Swanson, Donald A.
2010-01-01
The formation, evolution, collapse, and subsequent resurrection of a vent within Halema'uma'u Crater, Kilauea Volcano, produced energetic and varied degassing signals recorded by a nearby infrasound array between 2008 and early 2009. After 25 years of quiescence, a vent-clearing explosive burst on 19 March 2008 produced a clear, complex acoustic signal. Near-continuous harmonic infrasonic tremor followed this burst until 4 December 2008, when a period of decreased degassing occurred. The tremor spectra suggest volume oscillation and reverberation of a shallow gas-filled cavity beneath the vent. The dominant tremor peak can be sustained through Helmholtz oscillations of the cavity, while the secondary tremor peak and overtones are interpreted assuming acoustic resonance. The dominant tremor frequency matches the oscillation frequency of the gas emanating from the vent observed by video. Tremor spectra and power are also correlated with cavity geometry and dynamics, with the cavity depth estimated at ~219 m and volume ~3 x 106 m3 in November 2008. Over 21 varied degassing bursts were observed with extended burst durations and frequency content consistent with a transient release of gas exciting the cavity into resonance. Correlation of infrasound with seismicity suggests an open system connecting the atmosphere to the seismic excitation process at depth. Numerous degassing bursts produced very long period (0.03-0.1 Hz) infrasound, the first recorded at Kilauea, indicative of long-duration atmospheric accelerations. Kilauea infrasound appears controlled by the exsolution of gas from the magma, and the interaction of this gas with the conduits and cavities confining it.
Study on the Before Cavity Interaction in a Second Harmonic Gyrotron Using 3D CFDTD PIC Simulations
NASA Astrophysics Data System (ADS)
Lin, M. C.; Illy, S.; Thumm, M.; Jelonnek, J.
2016-10-01
A computational study on before cavity interaction (BCI) in a 28 GHz second harmonic (SH) gryotron for industrial applications has been performed using a 3-D conformal finite-difference time-domain (CFDTD) particle-in-cell (PIC) method. On the contrary to the after cavity interaction (ACI), i.e. beam wave interaction in the non-linear uptaper after the cavity, which has been widely investigated, the BCI, i.e. beam wave interaction in the non-linear downtaper before the cavity connected to the beam tunnel with an entrance, is less noticed and discussed. Usually the BCI might be considered easy to be eliminated. However, this is not always the case. As the SH gyrotron had been designed for SH TE12 mode operation, the first harmonic (FH) plays the main competition. In the 3-D CFDTD PIC simulations, a port boundary has been employed for the gyro-beam entrance of the gyrotron cavity instead of a metallic short one which is not reflecting a realistic situation as an FH backward wave oscillation (BWO) is competing with the desired SH generation. A numerical instability has been found and identified as a failure of the entrance port boundary caused by an evanescent wave or mode conversion. This indicates the entrance and downtaper are not fully cut-off for some oscillations. A further study shows that the undesired oscillation is the FH TE11 BWO mode concentrated around the beam tunnel entrance and downtaper. A mitigation strategy has been found to suppress this undesired BCI and avoid possible damage to the gun region.
Cavity hydration dynamics in cytochrome c oxidase and functional implications
Son, Chang Yun; Cui, Qiang
2017-01-01
Cytochrome c oxidase (CcO) is a transmembrane protein that uses the free energy of O2 reduction to generate the proton concentration gradient across the membrane. The regulation of competitive proton transfer pathways has been established to be essential to the vectorial transport efficiency of CcO, yet the underlying mechanism at the molecular level remains lacking. Recent studies have highlighted the potential importance of hydration-level change in an internal cavity that connects the proton entrance channel, the site of O2 reduction, and the putative proton exit route. In this work, we use atomistic molecular dynamics simulations to investigate the energetics and timescales associated with the volume fluctuation and hydration-level change in this central cavity. Extensive unrestrained molecular dynamics simulations (accumulatively ∼4 μs) and free energy computations for different chemical states of CcO support a model in which the volume and hydration level of the cavity are regulated by the protonation state of a propionate group of heme a3 and, to a lesser degree, the redox state of heme a and protonation state of Glu286. Markov-state model analysis of ∼2-μs trajectories suggests that hydration-level change occurs on the timescale of 100–200 ns before the proton-loading site is protonated. The computed energetic and kinetic features for the cavity wetting transition suggest that reversible hydration-level change of the cavity can indeed be a key factor that regulates the branching of proton transfer events and therefore contributes to the vectorial efficiency of proton transport. PMID:28973914
Assessment of thermal loads in the CERN SPS crab cavities cryomodule 1
Carra, F.; Apeland, J.; Calaga, R.; ...
2017-07-20
As a part of the HL-LHC upgrade, we designed a cryomodule to host two crab cavities for a first test with protons in the SPS machine. The evaluation of the cryomodule heat loads is essential to dimension the cryogenic infrastructure of the system. The current design features two cryogenic circuits. The first circuit adopts superfluid helium at 2 K to maintain the cavities in the superconducting state. The second circuit, based on helium gas at a temperature between 50 K and 70 K, is connected to the thermal screen, also serving as heat intercept for all the interfaces between themore » cold mass and the external environment. We present an overview of the heat loads to both circuits, and the combined numerical and analytical estimations. The heat load of each element is detailed for the static and dynamic scenarios, with considerations on the design choices for the thermal optimization of the most critical components.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marshall, J.R.; Hardin, R.T. Jr.
1987-07-07
This patent describes a nuclear reactor installation including means defining a fuel handling area and means defining a containment area separated from the fuel handling area and including a refuelling cavity; the improvement comprising: (a) a fuel transfer tube connecting the refuelling cavity with the fuel handling area; the fuel transfer tube having a first end in the fuel handling area and a second end in the refueling cavity; (b) valve means for opening and closing the first end; and (c) a hatch assembly mounted on the second end; the hatch assembly including (1) a hatch ring affixed to themore » fuel transfer tube at the second end the hatch ring has an integral annular seat surrounded by the hatch ring and defines a hatch opening in the second end of the fuel transfer tube; (2) a hatch cover adapts to be positioned on the annular seat for covering the hatch opening; (3) latching units are supported on the hatch ring about the hatch opening, each latching unit.« less
Wind turbine having a direct-drive drivetrain
Bevington, Christopher M.; Bywaters, Garrett L.; Coleman, Clint C.; Costin, Daniel P.; Danforth, William L.; Lynch, Jonathan A.; Rolland, Robert H.
2008-10-07
A wind turbine (100) comprising an electrical generator (108) that includes a rotor assembly (112). A wind rotor (104) that includes a wind rotor hub (124) is directly coupled to the rotor assembly via a simplified connection. The wind rotor and generator rotor assembly are rotatably mounted on a central spindle (160) via a bearing assembly (180). The wind rotor hub includes an opening (244) having a diameter larger than the outside diameter of the central spindle adjacent the bearing assembly so as to allow access to the bearing assembly from a cavity (380) inside the wind rotor hub. The spindle is attached to a turret (140) supported by a tower (136). Each of the spindle, turret and tower has an interior cavity (172, 176, 368) that permits personnel to traverse therethrough to the cavity of the wind rotor hub. The wind turbine further includes a frictional braking system (276) for slowing, stopping or keeping stopped the rotation of the wind rotor and rotor assembly.
Electro-thermo-optical simulation of vertical-cavity surface-emitting lasers
NASA Astrophysics Data System (ADS)
Smagley, Vladimir Anatolievich
Three-dimensional electro-thermal simulator based on the double-layer approximation for the active region was coupled to optical gain and optical field numerical simulators to provide a self-consistent steady-state solution of VCSEL current-voltage and current-output power characteristics. Methodology of VCSEL modeling had been established and applied to model a standard 850-nm VCSEL based on GaAs-active region and a novel intracavity-contacted 400-nm GaN-based VCSEL. Results of GaAs VCSEL simulation were in a good agreement with experiment. Correlations between current injection and radiative mode profiles have been observed. Physical sub-models of transport, optical gain and cavity optical field were developed. Carrier transport through DBRs was studied. Problem of optical fields in VCSEL cavity was treated numerically by the effective frequency method. All the sub-models were connected through spatially inhomogeneous rate equation system. It was shown that the conventional uncoupled analysis of every separate physical phenomenon would be insufficient to describe VCSEL operation.
Photon-Mediated Quantum Gate between Two Neutral Atoms in an Optical Cavity
NASA Astrophysics Data System (ADS)
Welte, Stephan; Hacker, Bastian; Daiss, Severin; Ritter, Stephan; Rempe, Gerhard
2018-02-01
Quantum logic gates are fundamental building blocks of quantum computers. Their integration into quantum networks requires strong qubit coupling to network channels, as can be realized with neutral atoms and optical photons in cavity quantum electrodynamics. Here we demonstrate that the long-range interaction mediated by a flying photon performs a gate between two stationary atoms inside an optical cavity from which the photon is reflected. This single step executes the gate in 2 μ s . We show an entangling operation between the two atoms by generating a Bell state with 76(2)% fidelity. The gate also operates as a cnot. We demonstrate 74.1(1.6)% overlap between the observed and the ideal gate output, limited by the state preparation fidelity of 80.2(0.8)%. As the atoms are efficiently connected to a photonic channel, our gate paves the way towards quantum networking with multiqubit nodes and the distribution of entanglement in repeater-based long-distance quantum networks.
Apparatus for detecting alpha radiation in difficult access areas
Steadman, P.; MacArthur, D.W.
1997-09-02
An electrostatic alpha radiation detector for measuring alpha radiation emitted from inside an enclosure comprising an electrically conductive expandable electrode for insertion into the enclosure is disclosed. After insertion, the electrically conductive expandable electrode is insulated from the enclosure and defines a decay cavity between the electrically conductive expandable electrode and the enclosure so that air ions generated in the decay cavity are electrostatically captured by the electrically conductive expandable electrode and the enclosure when an electric potential is applied between the electrically conductive expandable electrode and the enclosure. Indicator means are attached to the electrically conductive expandable electrode for indicating an electrical current produced by generation of the air ions generated in the decay cavity by collisions between air molecules and the alpha particles emitted from the enclosure. A voltage source is connected between the indicator means and the electrically conductive enclosure for creating an electric field between the electrically conductive expandable electrode and the enclosure. 4 figs.
EEG functional connectivity, axon delays and white matter disease.
Nunez, Paul L; Srinivasan, Ramesh; Fields, R Douglas
2015-01-01
Both structural and functional brain connectivities are closely linked to white matter disease. We discuss several such links of potential interest to neurologists, neurosurgeons, radiologists, and non-clinical neuroscientists. Treatment of brains as genuine complex systems suggests major emphasis on the multi-scale nature of brain connectivity and dynamic behavior. Cross-scale interactions of local, regional, and global networks are apparently responsible for much of EEG's oscillatory behaviors. Finite axon propagation speed, often assumed to be infinite in local network models, is central to our conceptual framework. Myelin controls axon speed, and the synchrony of impulse traffic between distant cortical regions appears to be critical for optimal mental performance and learning. Several experiments suggest that axon conduction speed is plastic, thereby altering the regional and global white matter connections that facilitate binding of remote local networks. Combined EEG and high resolution EEG can provide distinct multi-scale estimates of functional connectivity in both healthy and diseased brains with measures like frequency and phase spectra, covariance, and coherence. White matter disease may profoundly disrupt normal EEG coherence patterns, but currently these kinds of studies are rare in scientific labs and essentially missing from clinical environments. Copyright © 2014 International Federation of Clinical Neurophysiology. All rights reserved.
NASA Astrophysics Data System (ADS)
Zho, Chen-Chen; Farr, Erik P.; Glover, William J.; Schwartz, Benjamin J.
2017-08-01
We use one-electron non-adiabatic mixed quantum/classical simulations to explore the temperature dependence of both the ground-state structure and the excited-state relaxation dynamics of the hydrated electron. We compare the results for both the traditional cavity picture and a more recent non-cavity model of the hydrated electron and make definite predictions for distinguishing between the different possible structural models in future experiments. We find that the traditional cavity model shows no temperature-dependent change in structure at constant density, leading to a predicted resonance Raman spectrum that is essentially temperature-independent. In contrast, the non-cavity model predicts a blue-shift in the hydrated electron's resonance Raman O-H stretch with increasing temperature. The lack of a temperature-dependent ground-state structural change of the cavity model also leads to a prediction of little change with temperature of both the excited-state lifetime and hot ground-state cooling time of the hydrated electron following photoexcitation. This is in sharp contrast to the predictions of the non-cavity model, where both the excited-state lifetime and hot ground-state cooling time are expected to decrease significantly with increasing temperature. These simulation-based predictions should be directly testable by the results of future time-resolved photoelectron spectroscopy experiments. Finally, the temperature-dependent differences in predicted excited-state lifetime and hot ground-state cooling time of the two models also lead to different predicted pump-probe transient absorption spectroscopy of the hydrated electron as a function of temperature. We perform such experiments and describe them in Paper II [E. P. Farr et al., J. Chem. Phys. 147, 074504 (2017)], and find changes in the excited-state lifetime and hot ground-state cooling time with temperature that match well with the predictions of the non-cavity model. In particular, the experiments reveal stimulated emission from the excited state with an amplitude and lifetime that decreases with increasing temperature, a result in contrast to the lack of stimulated emission predicted by the cavity model but in good agreement with the non-cavity model. Overall, until ab initio calculations describing the non-adiabatic excited-state dynamics of an excess electron with hundreds of water molecules at a variety of temperatures become computationally feasible, the simulations presented here provide a definitive route for connecting the predictions of cavity and non-cavity models of the hydrated electron with future experiments.
Angiofibroma in a cockatiel (Nymphicus hollandicus).
Doss, G A; Miller, J L; Steinberg, H; Mans, C
2015-01-01
Human angiofibromas are rare and arise typically in the nasopharynx. In veterinary medicine they have only been described in the dog. Microscopically, angiofibromas consist of irregular groups of blood vessels within a stroma of connective tissue, with oedema and secondary inflammation often present. A cockatiel (Nymphicus hollandicus) was presented with an oral mass that consisted of aggregates of blood vessels surrounded by a connective tissue stroma, with the presence of oedema and secondary inflammation. Tumours of the oral cavity are uncommon in birds and to the authors' knowledge this is the first case of avian angiofibroma. Copyright © 2015 Elsevier Ltd. All rights reserved.
A designed metal-organic framework based on a metal-organic polyhedron.
Zou, Yang; Park, Mira; Hong, Seunghee; Lah, Myoung Soo
2008-05-28
A C(3) symmetric ligand with three 1,3-benzenedicarboxylate units has been used to construct a metal-organic framework with a (3,24)-connected network topology, where the nanometre-sized metal-organic cuboctahedra (MOCs) have been incorporated solely into a cubic close packing (CCP) arrangement, which led to superoctahedral and supertetrahedral cavities.
Eiting, Thomas P.; Perot, J. Blair; Dumont, Elizabeth R.
2015-01-01
The morphology of the nasal cavity in mammals with a good sense of smell includes features that are thought to improve olfactory airflow, such as a dorsal conduit that delivers odours quickly to the olfactory mucosa, an enlarged olfactory recess at the back of the airway, and a clear separation of the olfactory and respiratory regions of the nose. The link between these features and having a good sense of smell has been established by functional examinations of a handful of distantly related mammalian species. In this paper, we provide the first detailed examination of olfactory airflow in a group of closely related species that nevertheless vary in their sense of smell. We study six species of phyllostomid bats that have different airway morphologies and foraging ecologies, which have been linked to differences in olfactory ability or reliance. We hypothesize that differences in morphology correlate with differences in the patterns and rates of airflow, which in turn are consistent with dietary differences. To compare species, we make qualitative and quantitative comparisons of the patterns and rates of airflow through the olfactory region during both inhalation and exhalation across the six species. Contrary to our expectations, we find no clear differences among species in either the patterns of airflow through the airway or in rates of flow through the olfactory region. By and large, olfactory airflow seems to be conserved across species, suggesting that morphological differences appear to be driven by other mechanical demands on the snout, such as breathing and feeding. Olfactory ability may depend on other aspects of the system, such as the neurobiological processing of odours that work within the existing morphology imposed by other functional demands on the nasal cavity. PMID:25520358
Mechanisms for the Dissipation of Alfven Waves in Near-Earth Space Plasma
NASA Technical Reports Server (NTRS)
Singh, Nagendra; Khazanov, George; Krivorutsky, E. N.; Davis, John M. (Technical Monitor)
2002-01-01
Alfven waves are a major mechanism for the transport of electromagnetic energy from the distant part of the magnetosphere to the near-Earth space. This is especially true for the auroral and polar regions of the Earth. However, the mechanisms for their dissipation have remained illusive. One of the mechanisms is the formation of double layers when the current associated with Alfven waves in the inertial regime interact with density cavities, which either are generated nonlinearly by the waves themselves or are a part of the ambient plasma turbulence. Depending on the strength of the cavities, weak and strong double layers could form. Such double layers are transient; their lifetimes depend on that of the cavities. Thus they impulsively accelerate ions and electrons. Another mechanism is the resonant absorption of broadband Alfven- wave noise by the ions at the ion cyclotron frequencies. But this resonant absorption may not be possible for the very low frequency waves, and it may be more suited for electromagnetic ion cyclotron waves. A third mechanism is the excitation of secondary waves by the drifts of electrons and ions in the Alfven wave fields. It is found that under suitable conditions, the relative drifts between different ion species and/or between electrons and ions are large enough to drive lower hybrid waves, which could cause transverse accelerations of ions and parallel accelerations of electrons. This mechanism is being further studied by means of kinetic simulations using 2.5- and 3-D particle-in-cell codes. The ongoing modeling efforts on space weather require quantitative estimates of energy inputs of various kinds, including the electromagnetic energy. Our studies described here contribute to the methods of determining the estimates of the input from ubiquitous Alfven waves.
Rashid, Barnaly; Damaraju, Eswar; Pearlson, Godfrey D; Calhoun, Vince D
2014-01-01
Schizophrenia (SZ) and bipolar disorder (BP) share significant overlap in clinical symptoms, brain characteristics, and risk genes, and both are associated with dysconnectivity among large-scale brain networks. Resting state functional magnetic resonance imaging (rsfMRI) data facilitates studying macroscopic connectivity among distant brain regions. Standard approaches to identifying such connectivity include seed-based correlation and data-driven clustering methods such as independent component analysis (ICA) but typically focus on average connectivity. In this study, we utilize ICA on rsfMRI data to obtain intrinsic connectivity networks (ICNs) in cohorts of healthy controls (HCs) and age matched SZ and BP patients. Subsequently, we investigated difference in functional network connectivity, defined as pairwise correlations among the timecourses of ICNs, between HCs and patients. We quantified differences in both static (average) and dynamic (windowed) connectivity during the entire scan duration. Disease-specific differences were identified in connectivity within different dynamic states. Notably, results suggest that patients make fewer transitions to some states (states 1, 2, and 4) compared to HCs, with most such differences confined to a single state. SZ patients showed more differences from healthy subjects than did bipolars, including both hyper and hypo connectivity in one common connectivity state (dynamic state 3). Also group differences between SZ and bipolar patients were identified in patterns (states) of connectivity involving the frontal (dynamic state 1) and frontal-parietal regions (dynamic state 3). Our results provide new information about these illnesses and strongly suggest that state-based analyses are critical to avoid averaging together important factors that can help distinguish these clinical groups.
Behrenbruch, Corina; Hollande, Frédéric; Thomson, Benjamin; Michael, Michael; Warrier, Satish K; Lynch, Craig; Heriot, Alexander
2017-09-01
The peritoneum is the second most common site of metastasis after the liver and the only site of metastatic disease in approximately 25% of patients with colorectal cancer (CRC). In the past, peritoneal carcinomatosis in CRC was thought to be equivalent to distant metastasis; however, the transcoelomic spread of malignant cells is an acknowledged alternative pathway. Metastasectomy with curative intent is well accepted in patients with liver metastasis in CRC despite the paucity of randomized trials. Therefore, there is rationale for local treatment with peritonectomy to eliminate macroscopic disease, followed by hyperthermic intraperitoneal chemotherapy to destroy any residual free tumour cells within the peritoneal cavity. The aim of this paper is to summarize the current evidence for cytoreduction and hyperthermic intraperitoneal chemotherapy in the treatment of peritoneal carcinomatosis in CRC. © 2017 Royal Australasian College of Surgeons.
Water-walled microfluidics for high-optical finesse cavities
NASA Astrophysics Data System (ADS)
Maayani, Shai; Martin, Leopoldo L.; Carmon, Tal
2016-01-01
In submerged microcavities there is a tradeoff between resonant enhancement for spatial water and light overlap. Why not transform the continuously resonating optical mode to be fully contained in a water microdroplet per se? Here we demonstrate a sustainable 30-μm-pure water device, bounded almost completely by free surfaces, enabling >1,000,000 re-circulations of light. The droplets survive for >16 h using a technique that is based on a nano-water bridge from the droplet to a distant reservoir to compensate for evaporation. More than enabling a nearly-perfect optical overlap with water, atomic-level surface smoothness that minimizes scattering loss, and ~99% coupling efficiency from a standard fibre. Surface tension in our droplet is 8,000 times stronger than gravity, suggesting a new class of devices with water-made walls, for new fields of study including opto-capillaries.
Path-Length and the Misperception of Speech: Insights from Network Science and Psycholinguistics
NASA Astrophysics Data System (ADS)
Vitevitch, Michael S.; Goldstein, Rutherford; Johnson, Elizabeth
Using the analytical methods of network science we examined what could be retrieved from the lexicon when a spoken word is misperceived. To simulate misperceptions in the laboratory, we used a variant of the semantic associates task—the phonological associate task—in which participants heard an English word and responded with the first word that came to mind that sounded like the word they heard, to examine what people actually do retrieve from the lexicon when a spoken word is misperceived. Most responses were 1 link away from the stimulus word in the lexical network. Distant neighbors (words >1 link) were provided more often as responses when the stimulus word had low rather than high degree. Finally, even very distant neighbors tended to be connected to the stimulus word by a path in the lexical network. These findings have implications for the processing of spoken words, and highlight the valuable insights that can be obtained by combining the analytic tools of network science with the experimental tasks of psycholinguistics.
Hennawi, Joseph F; Prochaska, J Xavier; Cantalupo, Sebastiano; Arrigoni-Battaia, Fabrizio
2015-05-15
All galaxies once passed through a hyperluminous quasar phase powered by accretion onto a supermassive black hole. But because these episodes are brief, quasars are rare objects typically separated by cosmological distances. In a survey for Lyman-α emission at redshift z ≈ 2, we discovered a physical association of four quasars embedded in a giant nebula. Located within a substantial overdensity of galaxies, this system is probably the progenitor of a massive galaxy cluster. The chance probability of finding a quadruple quasar is estimated to be ∼10(-7), implying a physical connection between Lyman-α nebulae and the locations of rare protoclusters. Our findings imply that the most massive structures in the distant universe have a tremendous supply (≃10(11) solar masses) of cool dense (volume density ≃ 1 cm(-3)) gas, which is in conflict with current cosmological simulations. Copyright © 2015, American Association for the Advancement of Science.
Okamoto, Tsuyoshi; Ikezoe, Koji; Tamura, Hiroshi; Watanabe, Masataka; Aihara, Kazuyuki; Fujita, Ichiro
2011-01-01
In the primary visual cortex (V1) of some mammals, columns of neurons with the full range of orientation preferences converge at the center of a pinwheel-like arrangement, the ‘pinwheel center' (PWC). Because a neuron receives abundant inputs from nearby neurons, the neuron's position on the cortical map likely has a significant impact on its responses to the layout of orientations inside and outside its classical receptive field (CRF). To understand the positional specificity of responses, we constructed a computational model based on orientation preference maps in monkey V1 and hypothetical neuronal connections. The model simulations showed that neurons near PWCs displayed weaker but detectable orientation selectivity within their CRFs, and strongly reduced contextual modulation from extra-CRF stimuli, than neurons distant from PWCs. We suggest that neurons near PWCs robustly extract local orientation within their CRF embedded in visual scenes, and that contextual information is processed in regions distant from PWCs. PMID:22355631
Observations of H-alpha and microwave brightening caused by a distant solar flare
NASA Technical Reports Server (NTRS)
Kundu, M. R.; Bobrowsky, M.; Rust, D. M.
1983-01-01
Synthesized maps with integration times of 10 and 30 sec, based on the observation of three subflares at 6 cm and H-alpha 6563 A, indicate that most of the 6 cm burst emission originated in 10-15 arcsec features coincident with, or adjacent to, H-alpha flare kernels. During the onset of one of the subflares, 6 cm emission was discovered in a loop stretching over 100,000 km from the primary flare site in association with H-alpha flare-like brightness at the remote footpoint of the loop. Assuming a primary flare site origin for the energy of the distant brightening, about 4 x 10 to the 24th ergs/sec propagated along the connecting magnetic loop at a velocity of more than 6000 km/sec. It is suggested that the energy may have been carried by electrons originating in the high energy tail of the electron thermal velocity distribution, escaping from the primary flare site.
Origins of Allostery and Evolvability in Proteins: A Case Study.
Raman, Arjun S; White, K Ian; Ranganathan, Rama
2016-07-14
Proteins display the capacity for adaptation to new functions, a property critical for evolvability. But what structural principles underlie the capacity for adaptation? Here, we show that adaptation to a physiologically distinct class of ligand specificity in a PSD95, DLG1, ZO-1 (PDZ) domain preferentially occurs through class-bridging intermediate mutations located distant from the ligand-binding site. These mutations provide a functional link between ligand classes and demonstrate the principle of "conditional neutrality" in mediating evolutionary adaptation. Structures show that class-bridging mutations work allosterically to open up conformational plasticity at the active site, permitting novel functions while retaining existing function. More generally, the class-bridging phenotype arises from mutations in an evolutionarily conserved network of coevolving amino acids in the PDZ family (the sector) that connects the active site to distant surface sites. These findings introduce the concept that allostery in proteins could have its origins not in protein function but in the capacity to adapt. Copyright © 2016 Elsevier Inc. All rights reserved.
Fabry-Perot cavity cascaded sagnac loops for temperature and strain measurements
NASA Astrophysics Data System (ADS)
Shangguan, Chunmei; Zhang, Wen; Hei, Wei; Luo, Fei; Zhu, Lianqing
2018-04-01
The fabrication process and temperature and strain characterizations of an all-fiber sensor are presented. The sensing structure based on a Fabry-Perot cavity (FPC) and sagnac loops was proposed and experimentally demonstrated for measurements of temperature and strain. The FPC consists of a micropiece of chemical etched multimode fiber end face, welded with another single mode fiber. Then, the sagnac loops composed of polarization maintaining fiber was connected to the FPC. The sensor was fabricated and tested for temperature and strain. Experimental results show that sensitivity of temperature and strain is 0.71 ± 0.03 nm / ° C and 1.30 ± 0.01 pm / μɛ, respectively; the linearity are 0.9970 and 0.9996, respectively.
Stainless Steel to Titanium Bimetallic Transitions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaluzny, J. A.; Grimm, C.; Passarelli, D.
In order to use stainless steel piping in an LCLS-II (Linac Coherent Light Source Upgrade) cryomodule, stainless steel to titanium bimetallic transitions are needed to connect the stainless steel piping to the titanium cavity helium vessel. Explosion bonded stainless steel to titanium transition pieces and bimetallic transition material samples have been tested. A sample transition tube was subjected to tests and x-ray examinations between tests. Samples of the bonded joint material were impact and tensile tested at room temperature as well as liquid helium temperature. The joint has been used successfully in horizontal tests of LCLS-II cavity helium vessels andmore » is planned to be used in LCLS-II cryomodules. Results of material sample and transition tube tests will be presented.« less
Microimaging FT-IR of oral cavity tumours. Part III: Cells, inoculated tissues and human tissues
NASA Astrophysics Data System (ADS)
Conti, C.; Ferraris, P.; Giorgini, E.; Pieramici, T.; Possati, L.; Rocchetti, R.; Rubini, C.; Sabbatini, S.; Tosi, G.; Mariggiò, M. A.; Lo Muzio, L.
2007-05-01
The biochemistry of healthy and tumour cell cultures, inoculated tissues and oral cavity tissues have been studied by FT-IR Microscopy with the aim to relate spectral patterns with microbiological and histopathological findings. 'Supervised' and 'unsupervised' procedures of data handling afforded a satisfactory degree of accordance between spectroscopic and the other two techniques. In particular, changes in frequency and intensity of proteins, connective and nucleic acids vibrational modes as well as the visualization of biochemical single wave number or band ratio images, allowed an evaluation of the pathological changes. The spectroscopic patterns of inoculated tissues resulted quite similar to human tissues; differences of both types of sections with cellular lines could be explained by the influence of the environment.
Acoustic one-way mode conversion and transmission by sonic crystal waveguides
NASA Astrophysics Data System (ADS)
Ouyang, Shiliang; He, Hailong; He, Zhaojian; Deng, Ke; Zhao, Heping
2016-09-01
We proposed a scheme to achieve one-way acoustic propagation and even-odd mode switching in two mutually perpendicular sonic crystal waveguides connected by a resonant cavity. The even mode in the entrance waveguide is able to switch to the odd mode in the exit waveguide through a symmetry match between the cavity resonant modes and the waveguide modes. Conversely, the odd mode in the exit waveguide is unable to be converted into the even mode in the entrance waveguide as incident waves and eigenmodes are mismatched in their symmetries at the waveguide exit. This one-way mechanism can be applied to design an acoustic diode for acoustic integration devices and can be used as a convertor of the acoustic waveguide modes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bayn, I.; Mouradian, S.; Li, L.
2014-11-24
A scalable approach for integrated photonic networks in single-crystal diamond using triangular etching of bulk samples is presented. We describe designs of high quality factor (Q = 2.51 × 10{sup 6}) photonic crystal cavities with low mode volume (V{sub m} = 1.062 × (λ/n){sup 3}), which are connected via waveguides supported by suspension structures with predicted transmission loss of only 0.05 dB. We demonstrate the fabrication of these structures using transferred single-crystal silicon hard masks and angular dry etching, yielding photonic crystal cavities in the visible spectrum with measured quality factors in excess of Q = 3 × 10{sup 3}.
Central nervous system tissue heterotopia of the nose: case report and review of the literature
Altissimi, G; Ascani, S; Falcetti, S; Cazzato, C; Bravi, I
2009-01-01
Summary The Authors present a case of heterotopic central nervous system tissue observed in an 81-year-old male in the form of an ethmoidal polyp. A review of the literature indicates that this is a rare condition characterised by a connective tissue lesion with astrocytic and oligodendrocytic glial cells, which may be located outside the nasal pyramid in some cases and inside the nasal cavity in others. The most important diagnostic aspect involves differentiating these from meningoencephalocele, which maintains an anatomical connection with central nervous system tissue. Contrast-enhanced imaging is essential for diagnosis, as in cases of heterotopic central nervous system tissue, it will demonstrate that there are no connections with intra-cranial tissue. Endoscopic excision is the treatment of choice. PMID:20161881
NASA Astrophysics Data System (ADS)
Pavlík, Zbyšek; Jerman, Miloš; Fořt, Jan; Černý, Robert
2015-03-01
Hollow brick blocks have found widespread use in the building industry during the last decades. The increasing requirements to the thermal insulation properties of building envelopes given by the national standards in Europe led the brick producers to reduce the production of common solid bricks. Brick blocks with more or less complex systems of internal cavities replaced the traditional bricks and became dominant on the building ceramics market. However, contrary to the solid bricks where the thermal conductivity can easily be measured by standard methods, the complex geometry of hollow brick blocks makes the application of common techniques impossible. In this paper, a steady-state technique utilizing a system of two climatic chambers separated by a connecting tunnel for sample positioning is used for the determination of the thermal conductivity, thermal resistance, and thermal transmittance ( U value) of hollow bricks with the cavities filled by air, two different types of mineral wool, polystyrene balls, and foam polyurethane. The particular brick block is provided with the necessary temperature- and heat-flux sensors and thermally insulated in the tunnel. In the climatic chambers, different temperatures are set. After steady-state conditions are established in the measuring system, the effective thermal properties of the brick block are calculated using the measured data. Experimental results show that the best results are achieved with hydrophilic mineral wool as a cavity filler; the worst performance exhibits the brick block with air-filled cavities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ford, Denise C.; Cooley, Lance D.; Seidman, David N.
Niobium hydride is suspected to be a major contributor to degradation of the quality factor of niobium superconducting radio-frequency (SRF) cavities. In this study, we connect the fundamental properties of hydrogen in niobium to SRF cavity performance and processing. We modeled several of the niobium hydride phases relevant to SRF cavities and present their thermodynamic, electronic, and geometric properties determined from calculations based on density-functional theory. We find that the absorption of hydrogen from the gas phase into niobium is exothermic and hydrogen becomes somewhat anionic. The absorption of hydrogen by niobium lattice vacancies is strongly preferred over absorption intomore » interstitial sites. A single vacancy can accommodate six hydrogen atoms in the symmetrically equivalent lowest-energy sites and additional hydrogen in the nearby interstitial sites affected by the strain field: this indicates that a vacancy can serve as a nucleation center for hydride phase formation. Small hydride precipitates may then occur near lattice vacancies upon cooling. Vacancy clusters and extended defects should also be enriched in hydrogen, potentially resulting in extended hydride phase regions upon cooling. We also assess the phase changes in the niobium-hydrogen system based on charge transfer between niobium and hydrogen, the strain field associated with interstitial hydrogen, and the geometry of the hydride phases. The results of this study stress the importance of not only the hydrogen content in niobium, but also the recovery state of niobium for the performance of SRF cavities.« less
NASA Astrophysics Data System (ADS)
Ebraert, Evert; Van Erps, Jürgen; Beri, Stefano; Watté, Jan; Thienpont, Hugo
2014-05-01
Fibre-to-the-home (FTTH) networks provide an ideal means to reach the goal the European Union has set to provide 50 % of the households with a broadband connection faster than 100 Mb/s. Deployment of FTTH networks, which is still costly today, could be significantly boosted by novel ferrule-less connectors which don't require highly skilled personnel and allow installation in the field. We propose a ferrule-less connector in which two single-mode fibres (SMFs) are aligned and maintain physical contact by ensuring that at least one fibre is in a buckled state. To this end, we design a cavity in which a fibre can buckle in a controlled way. Using finite element analysis simulations to investigate the shape of the formed buckle for various buckling cavity lengths, we show that it can be accurately approximated by a cosine function. In addition, the optical performance of a buckled SMF is investigated by bending loss calculations and simulations. We show a good agreement between the analytical and the simulated bending loss results for a G.652 fibre at a wavelength of 1550 nm. Buckling cavity lengths smaller than 20 mm should be avoided to keep the optical bending loss due to buckling below 0.1 dB. In this case the cavity height should at least be 2 mm to avoid mechanical confinement of the fibre.
The effect of nonadiabaticity on the efficiency of quantum memory based on an optical cavity
NASA Astrophysics Data System (ADS)
Veselkova, N. G.; Sokolov, I. V.
2017-07-01
Quantum efficiency is an important characteristic of quantum memory devices that are aimed at recording the quantum state of light signals and its storing and reading. In the case of memory based on an ensemble of cold atoms placed in an optical cavity, the efficiency is restricted, in particular, by relaxation processes in the system of active atomic levels. We show how the effect of the relaxation on the quantum efficiency can be determined in a regime of the memory usage in which the evolution of signals in time is not arbitrarily slow on the scale of the field lifetime in the cavity and when the frequently used approximation of the adiabatic elimination of the quantized cavity mode field cannot be applied. Taking into account the effect of the nonadiabaticity on the memory quality is of interest in view of the fact that, in order to increase the field-medium coupling parameter, a higher cavity quality factor is required, whereas storing and processing of sequences of many signals in the memory implies that their duration is reduced. We consider the applicability of the well-known efficiency estimates via the system cooperativity parameter and estimate a more general form. In connection with the theoretical description of the memory of the given type, we also discuss qualitative differences in the behavior of a random source introduced into the Heisenberg-Langevin equations for atomic variables in the cases of a large and a small number of atoms.
NASA Astrophysics Data System (ADS)
Yamamoto, Takahiro; Nadaoka, Kazuo
2018-04-01
Atmospheric, watershed and coastal ocean models were integrated to provide a holistic analysis approach for coastal ocean simulation. The coupled model was applied to coastal ocean in the Philippines where terrestrial sediment loads provided from several adjacent watersheds play a major role in influencing coastal turbidity and are partly responsible for the coastal ecosystem degradation. The coupled model was validated using weather and hydrologic measurement to examine its potential applicability. The results revealed that the coastal water quality may be governed by the loads not only from the adjacent watershed but also from the distant watershed via coastal currents. This important feature of the multiple linkages can be quantitatively characterized by a "stress connectivity matrix", which indicates the complex underlying structure of environmental stresses in coastal ocean. The multiple stress connectivity concept shows the potential advantage of the integrated modelling approach for coastal ocean assessment, which may also serve for compensating the lack of measured data especially in tropical basins.
Li, Hui-Hui; Zhu, Hui; Liu, Li-Sheng; Huang, Yong; Guo, Jun; Li, Jie; Sun, Xin-Ping; Chang, Chun-Xiao; Wang, Zhe-Hai; Zhai, Kan
2015-07-13
Tumour necrosis factor-α (TNF-α) is critical in the regulation of inflammation and tumour progression. TNF-α-308G > A is associated with constitutively elevated TNF-α expression. The purpose of this study was to assess the association between TNF-α-308G > A and breast cancer (BC) risk by subtype and the connection between genotypes and clinical features of BC. A total of 768 patients and 565 controls were enrolled in this study, and genotypes were detected using the TaqMan assay. No effect on susceptibility for any BC subtype was found for the TNF-α-308 polymorphism in our study or in the pooled meta-analysis. This polymorphism was shown to be associated with age at menarche in all BC and in progesterone receptor-negative BC. Interestingly, triple negative breast cancer (TNBC) patients with TNF-α-308A had an increased risk of distant tumour metastasis (OR = 3.80, 95% CI: 1.31-11.02, P = 0.009). Multi-regression analysis showed that TNF-α-308A was also a risk factor for distant tumour metastasis after adjustment for tumour size and lymph node metastasis status (OR = 6.26, 95% CI: 1.88-20.87, P = 0.003). These findings indicate that TNF-α might play a distinct role in the progression of TNBC, especially in distant tumour metastasis of TNBC.
Nonlinear Wave Chaos and the Random Coupling Model
NASA Astrophysics Data System (ADS)
Zhou, Min; Ott, Edward; Antonsen, Thomas M.; Anlage, Steven
The Random Coupling Model (RCM) has been shown to successfully predict the statistical properties of linear wave chaotic cavities in the highly over-moded regime. It is of interest to extend the RCM to strongly nonlinear systems. To introduce nonlinearity, an active nonlinear circuit is connected to two ports of the wave chaotic 1/4-bowtie cavity. The active nonlinear circuit consists of a frequency multiplier, an amplifier and several passive filters. It acts to double the input frequency in the range from 3.5 GHz to 5 GHz, and operates for microwaves going in only one direction. Measurements are taken between two additional ports of the cavity and we measure the statistics of the second harmonic voltage over an ensemble of realizations of the scattering system. We developed an RCM-based model of this system as two chaotic cavities coupled by means of a nonlinear transfer function. The harmonics received at the output are predicted to be the product of three statistical quantities that describe the three elements correspondingly. Statistical results from simulation, RCM-based modeling, and direct experimental measurements will be compared. ONR under Grant No. N000141512134, AFOSR under COE Grant FA9550-15-1-0171,0 and the Maryland Center for Nanophysics and Advanced Materials.
Skirnisson, Karl; Sigurðardóttir, Ólöf G; Nielsen, Ólafur K
2016-08-01
Necropsies of 1010 rock ptarmigans (Lagopus muta) sampled in autumn 2006-2015 in northeast Iceland revealed Mesocestoides canislagopodis tetrathyridia infections in six birds (0.6 %), two juvenile birds (3 month old), and four adult birds (15 months or older). Four birds had tetrathyridia in the body cavity, one bird in the liver, and one bird both in the body cavity and the liver. There were more tetrathyridia in the body cavity of the two juveniles (c. 50 in each) than in three adults (10-40), possibly indicating a host-age-related tetrathyridia mortality. Approximately, half of tetrathyridia in the body cavity were free or loosely attached to the serosa, the other half were encapsulated in a thin, loose connective tissue stroma, frequently attached to the lungs and the liver. Tetrathyridia in the liver parenchyma incited variably intense inflammation. Tetrathyridia from the juvenile hosts were whitish, heart-shaped, and flattened, with unsegmented bodies with a slightly pointed posterior end. In the adult hosts, tetrathyridia were sometimes almost rectangular-shaped, slightly wider compared to those in the juveniles, but more than twice as long as the younger-aged tetrathyridia. Tetrathyridia infections are most likely acquired during the brief insectivorous feeding phase of ptarmigan chicks, and the tetrathyridia persist throughout the lifespan of the birds.
Zetterberg, Camilla; Richter, Hans O.; Forsman, Mikael
2015-01-01
Near work is associated with increased activity in the neck and shoulder muscles, but the underlying mechanism is still unknown. This study was designed to determine whether a dynamic change in focus, alternating between a nearby and a more distant visual target, produces a direct parallel change in trapezius muscle activity. Fourteen healthy controls and 12 patients with a history of visual and neck/shoulder symptoms performed a Near-Far visual task under three different viewing conditions; one neutral condition with no trial lenses, one condition with negative trial lenses to create increased accommodation, and one condition with positive trial lenses to create decreased accommodation. Eye lens accommodation and trapezius muscle activity were continuously recorded. The trapezius muscle activity was significantly higher during Near than during Far focusing periods for both groups within the neutral viewing condition, and there was a significant co-variation in time between accommodation and trapezius muscle activity within the neutral and positive viewing conditions for the control group. In conclusion, these results reveal a connection between Near focusing and increased muscle activity during dynamic changes in focus between a nearby and a far target. A direct link, from the accommodation/vergence system to the trapezius muscles cannot be ruled out, but the connection may also be explained by an increased need for eye-neck (head) stabilization when focusing on a nearby target as compared to a more distant target. PMID:25961299
Kanakis, Georgios A; Grimelius, Lars; Papaioannou, Dimitrios; Kaltsas, Gregory; Tsolakis, Apostolos V
2018-04-27
Altered expression of Insulin-like Growth Factor-1 (IGF-1), its receptor (IGF-1R), Connective Tissue Growth Factor (CTGF) and Hypoxia Inducible Factor-1 (HIF-1), has been implicated in tumorigenesis. So far, these factors have not been studied systematically in Pulmonary Carcinoids (PCs). To examine IGF-1, IGF-1R, CTGF and HIF-1 expression in PCs, and assess their prognostic value over established factors. Retrospective study of 121 PCs (104 Typical and 17 Atypical). The expression of growth factors was studied immunohistochemically and tumors were considered positive if immunoreactivity appeared in >50% of cells. All studied parameters were expressed in the majority of tumors (IGF-1, IGF-1R, CTGF and HIF-1, in 78.5%, 67%, 72% and 78%, respectively). Their expression tended to be more frequent in TCs and in tumors with Ki-67≤2% (significant only for HIF-1; 82 vs. 53%; p=0.023 and 83 vs. 63%; p=0.025 respectively). CTGF was the only factor correlated with more extensive disease (larger size; presence of lymph node and distant metastases). According to logistic regression analysis, only advanced age, Ki-67≥3.4% and lymph node involvement could predict the development of distant metastases. IGF-1, IGF-1R, CTGF and HIF-1 are avidly expressed in PCs; however, their presence did not appear to be of statistically significant value over established prognostic factors.
Zetterberg, Camilla; Richter, Hans O; Forsman, Mikael
2015-01-01
Near work is associated with increased activity in the neck and shoulder muscles, but the underlying mechanism is still unknown. This study was designed to determine whether a dynamic change in focus, alternating between a nearby and a more distant visual target, produces a direct parallel change in trapezius muscle activity. Fourteen healthy controls and 12 patients with a history of visual and neck/shoulder symptoms performed a Near-Far visual task under three different viewing conditions; one neutral condition with no trial lenses, one condition with negative trial lenses to create increased accommodation, and one condition with positive trial lenses to create decreased accommodation. Eye lens accommodation and trapezius muscle activity were continuously recorded. The trapezius muscle activity was significantly higher during Near than during Far focusing periods for both groups within the neutral viewing condition, and there was a significant co-variation in time between accommodation and trapezius muscle activity within the neutral and positive viewing conditions for the control group. In conclusion, these results reveal a connection between Near focusing and increased muscle activity during dynamic changes in focus between a nearby and a far target. A direct link, from the accommodation/vergence system to the trapezius muscles cannot be ruled out, but the connection may also be explained by an increased need for eye-neck (head) stabilization when focusing on a nearby target as compared to a more distant target.
Anatomy, Physiology and Function of the Auditory System
NASA Astrophysics Data System (ADS)
Kollmeier, Birger
The human ear consists of the outer ear (pinna or concha, outer ear canal, tympanic membrane), the middle ear (middle ear cavity with the three ossicles malleus, incus and stapes) and the inner ear (cochlea which is connected to the three semicircular canals by the vestibule, which provides the sense of balance). The cochlea is connected to the brain stem via the eighth brain nerve, i.e. the vestibular cochlear nerve or nervus statoacusticus. Subsequently, the acoustical information is processed by the brain at various levels of the auditory system. An overview about the anatomy of the auditory system is provided by Figure 1.
The New Concept of Univentricular Heart
Frescura, Carla; Thiene, Gaetano
2014-01-01
The concept of univentricular heart moved from hearts with only one ventricle connected with atria [double inlet ventricle or absent atrioventricular (AV) connection] to hearts not amenable to biventricular repair, namely hearts with two ventricles unable to sustain separately pulmonary and systemic circulations in sequence. In the latter definition, even hearts with one hypoplastic ventricle are considered “functional” univentricular hearts. They include pulmonary/aortic atresia or severe stenosis with hypoplastic ventricle, and rare conditions like huge intramural cardiac tumors and Ebstein anomaly with extreme atrialization of right ventricular cavity. In this setting, the surgical repair is univentricular with “Fontan” operation, bypassing the ventricular mass. In other words, functionally univentricular heart is a condition in which, after surgery, only one ventricle sustain systemic circulation. Univentricular hearts (double inlet or absent AV connection) almost invariably show two ventricular chambers, one main and one accessory, which lacks an inlet portion. The latter is located posteriorly when morphologically left and anteriorly when morphologically right. As far as double inlet left ventricle, this is usually associated with discordant ventriculo-arterial (VA) connection (transposition of the great arteries) and all the blood flow to the aorta, which takes origin from the hypoplastic anterior right ventricle, is ventricular septal defect (bulbo-ventricular foramen) dependent. If restrictive, an aortic arch obstruction may be present. Double inlet left ventricle may be rarely associated with VA concordance (Holmes heart). As far as double inlet right ventricle with posterior hypoplastic left ventricular cavity, ventriculo-arterial connection is usually of double outlet type; thus the term double inlet–outlet right ventricle may be coined. Absent right or left AV connection may develop in the setting of both d- or l-loop, whatever the situs. In this condition, the contra-lateral patent AV valve may be either mitral or tricuspid in terms of morphology and the underlying ventricle (main chamber) either morphologically left or right. Establishing the loop, whatever right or left (also called right or left ventricular topology), is a fundamental step in the segmental-sequential analysis of congenital heart disease. PMID:25072035
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fraser, Kevin C.; Shave, A.; Savage, A.
Migratory aerial insectivores are among the fastest declining avian group, but our understanding of these trends has been limited by poor knowledge of migratory connectivity and the identification of critical habitat across the vast distances they travel annually. Using new, archival GPS loggers, we tracked individual purple martins ( Progne subis) from breeding colonies across North America to determine precise (<10m) locations of migratory and overwintering roost locations in South America and to test hypotheses for fine-scale migratory connectivity and habitat use. We discovered weak migratory connectivity at the roost scale, and extensive, fine-scale mixing of birds in the Amazonmore » from distant (>2000 km) breeding sites, with some individuals sharing the same roosting trees. Despite vast tracts of contiguous forest in this region, birds occupied a much more limited habitat, with most (56%) roosts occurring on small habitat islands that were strongly associated with water. Only 17% of these roosts were in current protected areas. As a result, these data reflect a critical advance in our ability to remotely determine precise migratory connectivity and habitat selection across vast spatial scales, enhancing our understanding of population dynamics and enabling more effective conservation of species at risk.« less
Fraser, Kevin C.; Shave, A.; Savage, A.; ...
2016-07-27
Migratory aerial insectivores are among the fastest declining avian group, but our understanding of these trends has been limited by poor knowledge of migratory connectivity and the identification of critical habitat across the vast distances they travel annually. Using new, archival GPS loggers, we tracked individual purple martins ( Progne subis) from breeding colonies across North America to determine precise (<10m) locations of migratory and overwintering roost locations in South America and to test hypotheses for fine-scale migratory connectivity and habitat use. We discovered weak migratory connectivity at the roost scale, and extensive, fine-scale mixing of birds in the Amazonmore » from distant (>2000 km) breeding sites, with some individuals sharing the same roosting trees. Despite vast tracts of contiguous forest in this region, birds occupied a much more limited habitat, with most (56%) roosts occurring on small habitat islands that were strongly associated with water. Only 17% of these roosts were in current protected areas. As a result, these data reflect a critical advance in our ability to remotely determine precise migratory connectivity and habitat selection across vast spatial scales, enhancing our understanding of population dynamics and enabling more effective conservation of species at risk.« less
Borra, Elena; Visco-Comandini, Federica; Averbeck, Bruno B.
2017-01-01
The statistical structure of intrinsic parietal and parieto-frontal connectivity in monkeys was studied through hierarchical cluster analysis. Based on their inputs, parietal and frontal areas were grouped into different clusters, including a variable number of areas that in most instances occupied contiguous architectonic fields. Connectivity tended to be stronger locally: that is, within areas of the same cluster. Distant frontal and parietal areas were targeted through connections that in most instances were reciprocal and often of different strength. These connections linked parietal and frontal clusters formed by areas sharing basic functional properties. This led to five different medio-laterally oriented pillar domains spanning the entire extent of the parieto-frontal system, in the posterior parietal, anterior parietal, cingulate, frontal, and prefrontal cortex. Different information processing streams could be identified thanks to inter-domain connectivity. These streams encode fast hand reaching and its control, complex visuomotor action spaces, hand grasping, action/intention recognition, oculomotor intention and visual attention, behavioral goals and strategies, and reward and decision value outcome. Most of these streams converge on the cingulate domain, the main hub of the system. All of them are embedded within a larger eye–hand coordination network, from which they can be selectively set in motion by task demands. PMID:28275714
Predictors of survival in mucosal melanoma of the head and neck.
Jethanamest, Daniel; Vila, Peter M; Sikora, Andrew G; Morris, Luc G T
2011-10-01
The head and neck is the most common site of mucosal melanoma, a cancer with poor prognosis. In contrast to cutaneous melanoma, mucosal melanoma of the head and neck (MMHN) is uncommon, with limited data regarding outcomes and prognostic factors drawn from small, single-institution case series. In order to identify factors predictive of survival, we analyzed MMHN outcomes in a large US cohort. MMHN cases (n = 815) diagnosed in the USA between 1973 and 2007 were analyzed in the Surveillance, Epidemiology, and End Results registry, and cause of death was individually determined in 778 (95.5%) cases. Kaplan-Meier survival analysis and Cox proportional hazards regression were used to analyze prognostic variables. Disease-specific survival status was determined in 778 (95.5%) cases. The 5- and 10-year rates of overall survival (OS) were 25.2 and 12.2%; disease-specific survival (DSS), 32.4 and 19.3%. On multivariable analysis, anatomic primary site was an independent predictor of OS and DSS, with tumors in the nasal cavity and oral cavity associated with survival superior to tumors in the nasopharynx and paranasal sinuses. Age > 70 years, tumor size, nodal status, and distant metastasis status were additional independent predictors of poorer survival. In this large cohort of patients with MMHN, we have identified several novel factors robustly predictive of overall and melanoma-specific survival.
Sarria-S, Fabio A.; Morris, Glenn K.; Windmill, James F. C.; Jackson, Joseph; Montealegre-Z, Fernando
2014-01-01
This article reports the discovery of a new genus and three species of predaceous katydid (Insecta: Orthoptera) from Colombia and Ecuador in which males produce the highest frequency ultrasonic calling songs so far recorded from an arthropod. Male katydids sing by rubbing their wings together to attract distant females. Their song frequencies usually range from audio (5 kHz) to low ultrasonic (30 kHz). However, males of Supersonus spp. call females at 115 kHz, 125 kHz, and 150 kHz. Exceeding the human hearing range (50 Hz–20 kHz) by an order of magnitude, these insects also emit their ultrasound at unusually elevated sound pressure levels (SPL). In all three species these calls exceed 110 dB SPL rms re 20 µPa (at 15 cm). Males of Supersonus spp. have unusually reduced forewings (<0.5 mm2). Only the right wing radiates appreciable sound, the left bears the file and does not show a particular resonance. In contrast to most katydids, males of Supersonus spp. position and move their wings during sound production so that the concave aspect of the right wing, underlain by the insect dorsum, forms a contained cavity with sharp resonance. The observed high SPL at extreme carrier frequencies can be explained by wing anatomy, a resonant cavity with a membrane, and cuticle deformation. PMID:24901234
Numerical Simulation of Flow in Fluidic Valves in Rotating Detonation Engines
NASA Astrophysics Data System (ADS)
Gopalakrishnan, Nandini
Rotating detonation engines (RDE) have received considerable research attention in recent times for use in propulsion systems. The cycle frequency of operation of an RDE can be as high as 10,000 Hz. Conventional mechanical valves cannot operate at such high frequencies, leading to the need for propellant injectors or valves with no moving parts. A fluidic valve is such a valve and is the focus of this study. The valve consists of an orifice connected to a constant area plenum cavity which operates at constant pressure. The fluidic valve supplies propellants to the detonation tube through the orifice. Hydrogen - oxygen detonation is studied in a tube with fluidic valves. A detailed 19-step chemical reaction mechanism has been used to model detonation and the flow simulated in ANSYS Fluent. This research aims to determine the location of contact surface in the cavity and the time taken for the contact surface to leave the valve after a shock wave has passed through it. This will help us understand if the steady-state flow in the cavity is comprised of detonation products or fresh propellants.
NASA Astrophysics Data System (ADS)
Kadowaki, Kazuo; Watanabe, Chiharu; Minami, Hidetoshi; Yamamoto, Takashi; Kashiwagi, Takanari; Klemm, Richard
2014-03-01
Terahertz (THz) electromagnetic radiation emitted from high-Tc superconducting Bi2Sr2CaCu2O8+δ mesa structures in the case of single mesa and series-connected mesas is investigated by the FTIR spectroscopic technique while observing its temperature distribution simultaneously by a SiC photoluminescence technique. Changing the bias level, sudden jumps of the hot-spot position were clearly observed. Although the radiation intensity changes drastically associated with the jump of the hot spot position, the frequency is unaffected as long as the voltage per junction is kept constant. Since the frequency of the intense radiation satisfies the cavity resonance condition, we confirmed that the cavity resonance is of primarily importance for the synchronization of whole intrinsic Josephson junctions in the mesa for high power radiation. This work was supported in part by the Grant-in-Aid for challenging Exploratory Research, the Ministry of Education, Culture, Sports, Science & Technology (MEXT).
Seismic resonances of acoustic cavities
NASA Astrophysics Data System (ADS)
Schneider, F. M.; Esterhazy, S.; Perugia, I.; Bokelmann, G.
2016-12-01
The goal of an On-Site Inspection (OSI) is to clarify at a possible testsite whether a member state of the Comprehensive nuclear Test Ban Treaty (CTBT)has violated its rules by conducting a underground nuclear test. Compared toatmospheric and underwater tests underground nuclear explosions are the mostdifficult to detect.One primary structural target for the field team during an OSI is the detectionof an underground cavity, created by underground nuclear explosions. Theapplication of seismic-resonances of the cavity for its detection has beenproposed in the CTBT by mentioning "resonance seismometry" as possibletechnique during OSIs. We modeled the interaction of a seismic wave-field withan underground cavity by a sphere filled with an acoustic medium surrounded byan elastic full space. For this setting the solution of the seismic wave-fieldcan be computed analytically. Using this approach the appearance of acousticresonances can be predicted in the theoretical calculations. Resonance peaksappear in the spectrum derived for the elastic domain surrounding the acousticcavity, which scale in width with the density of the acoustic medium. For lowdensities in the acoustic medium as for an gas-filled cavity, the spectralpeaks become very narrow and therefore hard to resolve. The resonancefrequencies, however can be correlated to the discrete set of eigenmodes of theacoustic cavity and can thus be predicted if the dimension of the cavity isknown. Origin of the resonance peaks are internal reverberations of wavescoupling in the acoustic domain and causing an echoing signal that couples outto the elastic domain again. In the gas-filled case the amplitudes in timedomain are very low.Beside theoretical considerations we seek to find real data examples fromsimilar settings. As example we analyze a 3D active seismic data set fromFelsőpetény, Hungary that has been conducted between 2012 and 2014 on behalf ofthe CTBTO. In the subsurface of this area a former clay mine is situated, whichis connected to a karst cave of 30 m diameter in 70 m depth. Our aim is toinvestigate whether resonances predicted from theoretical models can be alsoobserved in data from such real experiments. Observation of spectral resonantpeaks could serve as the foundation of a cavity detection method that could beutilized for nuclear verification.
Aerodynamic seals for rotary machine
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bidkar, Rahul Anil; Cirri, Massimiliano; Thatte, Azam Mihir
2016-02-09
An aerodynamic seal assembly for a rotary machine includes multiple sealing device segments disposed circumferentially intermediate to a stationary housing and a rotor. Each of the segments includes a shoe plate with a forward-shoe section and an aft-shoe section having multiple labyrinth teeth therebetween facing the rotor. The sealing device segment also includes multiple flexures connected to the shoe plate and to a top interface element, wherein the multiple flexures are configured to allow the high pressure fluid to occupy a forward cavity and the low pressure fluid to occupy an aft cavity. Further, the sealing device segments include amore » secondary seal attached to the top interface element at one first end and positioned about the flexures and the shoe plate at one second end.« less
Insulation assembly for electric machine
Rhoads, Frederick W.; Titmuss, David F.; Parish, Harold; Campbell, John D.
2013-10-15
An insulation assembly is provided that includes a generally annularly-shaped main body and at least two spaced-apart fingers extending radially inwards from the main body. The spaced-apart fingers define a gap between the fingers. A slot liner may be inserted within the gap. The main body may include a plurality of circumferentially distributed segments. Each one of the plurality of segments may be operatively connected to another of the plurality of segments to form the continuous main body. The slot liner may be formed as a single extruded piece defining a plurality of cavities. A plurality of conductors (extendable from the stator assembly) may be axially inserted within a respective one of the plurality of cavities. The insulation assembly electrically isolates the conductors in the electric motor from the stator stack and from other conductors.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, T. J.; Weisend, II, J. G.
The TESLA collaboration developed a unique variant of SRF cryomodule designs, the chief feature being use of the large, low pressure helium vapor return pipe as the structural support backbone of the cryomodule. Additional innovative features include all cryogenic piping within the cryomodule (no parallel external cryogenic transfer line), long strings of RF cavities within a single cryomodule, and cryomodules connected in series. Several projects, including FLASH and XFEL at DESY, LCLS-II at SLAC, and the ILC technical design have adopted this general design concept. Advantages include saving space by eliminating the external transfer line, relatively tight packing of RFmore » cavities along the beamline due to fewer warm-cold transitions, and potentially lower costs. However, a primary disadvantage is the relative lack of independence for warm-up, replacement, and cool-down of individual cryomodules.« less
NASA Astrophysics Data System (ADS)
Mason, J. M.; Fahy, F. J.
1988-07-01
Double-leaf partitions are often utilized in situations requiring low weight structures with high transmission loss, an example of current interest being the fuselage walls of propeller-driven aircraft. In this case, acoustic excitation is periodic and, if one of the frequencies of excitation lies in the region of the fundamental mass-air-mass frequency of the partition, insulation performance is considerably less than desired. The potential effectiveness of tuned Helmholtz resonators connected to the partition cavity is investigated as a method of improving transmission loss. This is demonstrated by a simple theoretical model and then experimentally verified. Results show that substantial improvements may be obtained at and around the mass-air-mass frequency for a total resonator volume 15 percent of the cavity volume.
Carlsten, B.E.; Haynes, W.B.
1998-02-03
A discrete monotron oscillator for use in a high power microwave device is formed with a microwave oscillator having a half-wavelength resonant coaxial microwave cavity operating in fundamental TEM mode for microwave oscillation with an inner conductor defining a drift tube for propagating an electron beam and an outer conductor coaxial with the inner conductor. The inner conductor defines a modulating gap and an extraction gap downstream of the modulating gap. The modulating gap and the extraction gap connect the coaxial microwave cavity with the drift tube so that energy for the microwave oscillation is extracted from the electron beam at the extraction gap and modulates the electron beam at the modulating gap. For high power operation, an annular electron beam is used. 8 figs.
Carlsten, Bruce E.; Haynes, William B.
1998-01-01
A discrete monotron oscillator for use in a high power microwave device is formed with a microwave oscillator having a half-wavelength resonant coaxial microwave cavity operating in fundamental TEM mode for microwave oscillation with an inner conductor defining a drift tube for propagating an electron beam and an outer conductor coaxial with the inner conductor. The inner conductor defines a modulating gap and an extraction gap downstream of the modulating gap. The modulating gap and the extraction gap connect the coaxial microwave cavity with the drift tube so that energy for the microwave oscillation is extracted from the electron beam at the extraction gap and modulates the electron beam at the modulating gap. For high power operation, an annular electron beam is used.
A nasal osteoma with an acute course in a Japanese Black heifer
SATO, Reiichiro; UNE, Yumi; MADARAME, Hiroo; HANAMI, Hyougo; KANAI, Eiichi; MURAKAMI, Hironobu; TSUKAMOTO, Atsushi; SUZUKI, Takehito; OCHIAI, Hideharu; KIKUCHI, Masato; TANAKA, Hidekazu; ONDA, Ken
2017-01-01
A 14-month-old Japanese Black heifer presented with unilateral epistaxis and mild swelling of the right face. Radiography revealed a mass with increased radiopacity on the right side of the nasal bridge, extending to the left side. Intranasal endoscopy confirmed a large tumor-like structure protruding into the nasal cavity. Following euthanasia, cranial computed tomography (CT) was performed, revealing a tumor 24.3 × 17.5 × 14.8 cm in size. The tumor occupied the entire right nasal cavity and the frontal and sphenoid sinuses. Histopathological examination revealed that the tumor consisted of well-differentiated trabecular bones and loose connective tissue. Based on these findings, a diagnosis of osteoma was established. This report describes a case of osteoma with an acute course in a Japanese Black heifer. PMID:28579581
Managing a chest tube and drainage system.
Durai, Rajaraman; Hoque, Happy; Davies, Tony W
2010-02-01
Intercostal drainage tubes (ie, chest tubes) are inserted to drain the pleural cavity of air, blood, pus, or lymph. The water-seal container connected to the chest tube allows one-way movement of air and liquid from the pleural cavity. The container should not be changed unless it is full, and the chest tube should not be clamped unnecessarily. After a chest tube is inserted, a nurse trained in chest-tube management is responsible for managing the chest tube and drainage system. This entails monitoring the chest-tube position, controlling fluid evacuation, identifying when to change or empty the containers, and caring for the tube and drainage system during patient transport. This article provides an overview of indications, insertion techniques, and management of chest tubes. Copyright 2010 AORN, Inc. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Weber, Steven; Murch, K. W.; Chantasri, A.; Dressel, J.; Jordan, A. N.; Siddiqi, I.
2014-03-01
We use weak measurements to track individual quantum trajectories of a superconducting qubit embedded in a microwave cavity. Using a near-quantum-limited parametric amplifier, we selectively measure either the phase or amplitude of the cavity field, and thereby confine trajectories to either the equator or a meridian of the Bloch sphere. We analyze ensembles of trajectories to determine statistical properties such as the most likely path and most likely time connecting pre and post-selected quantum states. We compare our results with theoretical predictions derived from an action principle for continuous quantum measurement. Furthermore, by introducing a qubit drive, we investigate the interplay between unitary state evolution and non-unitary measurement dynamics. This work was supported by the IARPA CSQ program and the ONR.
Study of Evaporation Rate of Water in Hydrophobic Confinement using Forward Flux Sampling
NASA Astrophysics Data System (ADS)
Sharma, Sumit; Debenedetti, Pablo G.
2012-02-01
Drying of hydrophobic cavities is of interest in understanding biological self assembly, protein stability and opening and closing of ion channels. Liquid-to-vapor transition of water in confinement is associated with large kinetic barriers which preclude its study using conventional simulation techniques. Using forward flux sampling to study the kinetics of the transition between two hydrophobic surfaces, we show that a) the free energy barriers to evaporation scale linearly with the distance between the two surfaces, d; b) the evaporation rates increase as the lateral size of the surfaces, L increases, and c) the transition state to evaporation for sufficiently large L is a cylindrical vapor cavity connecting the two hydrophobic surfaces. Finally, we decouple the effects of confinement geometry and surface chemistry on the evaporation rates.
[Simplified identification and filter device of carbon dioxide].
Mei, Xue-qin; Zhang, Yi-ping
2009-11-01
This paper presents the design and implementation ways of a simplified device to identify and filter carbon dioxide. The gas went through the test interface which had wet litmus paper before entering the abdominal cavity. Carbon dioxide dissolving in water turned acidic, making litmus paper change color to identify carbon dioxide, in order to avoid malpractice by connecting the wrong gas when making Endoscopic surgery.
Coherent perfect rotation theory: connections with, and consequences beyond, the anti-laser
NASA Astrophysics Data System (ADS)
Crescimanno, Michael; Andrews, James; Zhou, Chuanhong; Baker, Michael
2014-05-01
Coherent Perfect Rotation (CPR) phenomena are a reversible generalization of the anti-laser. By evaluating CPR in a broad variety of common optical systems, including optical cavities and DFB and DBR structures, we illustrate its unique threshold and resonance features. This study builds intuition critical to assessing the utility of CPR in optical devices, and we detail it in a concrete application.
Improving Perception to Make Distant Connections Closer
Goldstone, Robert L.; Landy, David; Brunel, Lionel C.
2011-01-01
One of the challenges for perceptually grounded accounts of high-level cognition is to explain how people make connections and draw inferences between situations that superficially have little in common. Evidence suggests that people draw these connections even without having explicit, verbalizable knowledge of their bases. Instead, the connections are based on sub-symbolic representations that are grounded in perception, action, and space. One reason why people are able to spontaneously see relations between situations that initially appear to be unrelated is that their eventual perceptions are not restricted to initial appearances. Training and strategic deployment allow our perceptual processes to deliver outputs that would have otherwise required abstract or formal reasoning. Even without people having any privileged access to the internal operations of perceptual modules, these modules can be systematically altered so as to better serve our high-level reasoning needs. Moreover, perceptually based processes can be altered in a number of ways to closely approximate formally sanctioned computations. To be concrete about mechanisms of perceptual change, we present 21 illustrations of ways in which we alter, adjust, and augment our perceptual systems with the intention of having them better satisfy our needs. PMID:22207861
Resurgence flows in porous media
NASA Astrophysics Data System (ADS)
Adler, P. M.; Mityushev, V.
2009-12-01
Porous media are generally described by the Darcy equation when the length scales are sufficiently large with respect to the pore scale. This approach is also applicable when the media are heterogeneous, i.e., when permeability varies with space which is the most common case. In addition, real media are very often fractured; for a long time, this complex physical problem has been schematized by the double porosity model devised by Barenblatt. More recently, these fractured media have been addressed with a detailed description of the fractures and of their hydrodynamic interaction with the surrounding porous medium. There is another situation which occurs frequently in underground studies. One well is connected to a distant well while it is not connected to closer wells. Such a situation can only be understood if there is a direct link between the two connected wells and if this link has little if any hydrodynamic interaction with the porous medium that it crosses. This link can be a fracture or more likely a set of fractures. This phenomenon is called resurgence because of the obvious analogy with rivers which suddenly disappear underground and go out at the ground surface again. Similar ideas have already been developed in other fields. In Physics, random networks limited to nearest neighbors have been recently extended to small world models where distant vertices can be related directly by a link. The electrical testing of porous media by electrical probes located at the walls (electrical tomography) has been used frequently in Geophysics since it is a non-invasive technique; this classical technique corresponds exactly to the situation addressed here from a different perspective. Media with resurgences consist of a double structure. The first one which is continuous is described by Darcy law as usual. The second one models the resurgences by capillaries with impermeable walls which relate distant points of the continuous medium. These two structures have already been studied separately in previous works (see (1) and the literature therein). Networks were addressed by graph theory and an extensive literature has been devoted to studies of porous media on the Darcy scale. For sake of simplicity, a simple physical presentation and elementary solutions are first given for one dimensional structures which display unexpected features such as an apparent back flow which goes against the main pressure gradient. Then, a general formulation is proposed which involves some non local aspects. When the sizes of the connection zones between the network and the continuous medium are assumed to be small with respect to any linear size in the continuous medium, analytical solutions are obtained in two or three dimensions for spatially periodic structures which are adequate to model spatially homogenous media. The equivalent permeability of the medium is determined. Some elementary examples are worked out in two and three dimensions. Paradoxical flow patterns are obtained with back flow even with local resurgences. Unsteady problems are presently studied. (1) Adler, P.M. Porous media. Geometry and transport. Butterworth-Heinemann, Stoneham, Ma, 1992.
The magnetic topology of the plasmoid flux rope in a MHD-simulation of magnetotail reconnection
NASA Technical Reports Server (NTRS)
Birn, J.; Hesse, M.
1990-01-01
On the basis of a 3D MHD simulation, the magnetic topology of a plasmoid that forms by a localized reconnection process in a magnetotail configuration (including a net dawn-dusk magnetic field component B sub y N is discussed. As a consequence of B sub y N not equalling 0, the plasmoid assumes a helical flux rope structure rather than an isolated island or bubble structure. Initially all field lines of the plasmoid flux rope remain connected with the earth, while at later times a gradually increasing amount of flux tubes becomes separated, connecting to either the distant boundary or to the flank boundaries. In this stage, topologically different flux tubes become tangled and wrapped around each other, consistent with predictions on the basis of an ad hoc plasmoid model.
Surface Sites for Engineering Allosteric Control in Proteins
Lee, Jeeyeon; Natarajan, Madhusudan; Nashine, Vishal C.; Socolich, Michael; Vo, Tina; Russ, William P.; Benkovic, Stephen J.; Ranganathan, Rama
2010-01-01
Statistical analyses of protein families reveal networks of coevolving amino acids that functionally link distantly positioned functional surfaces. Such linkages suggest a concept for engineering allosteric control into proteins: The intramolecular networks of two proteins could be joined across their surface sites such that the activity of one protein might control the activity of the other. We tested this idea by creating PAS-DHFR, a designed chimeric protein that connects a light-sensing signaling domain from a plant member of the Per/Arnt/Sim (PAS) family of proteins with Escherichia coli dihydrofolate reductase (DHFR). With no optimization, PAS-DHFR exhibited light-dependent catalytic activity that depended on the site of connection and on known signaling mechanisms in both proteins. PAS-DHFR serves as a proof of concept for engineering regulatory activities into proteins through interface design at conserved allosteric sites. PMID:18927392
Integrated Social and QoS Trust-Based Routing in Mobile Ad Hoc Delay Tolerant Networks
2010-11-15
d-connectivity, honesty, or unselfishness) with: encounter*,. , A ^// m = / (3) {•p ounter,x r. , . .-, ( Ti x m (t), ifm =j ^indirect. X, T...take into account node »’ s belief in node m in the calculation ofT(jreet’ x(t + At). This models the decay of trust as trust is derived from a distant...directly based on node /’ s past experiences with node m up to time t + At, including the current encounter. Taking the fact that /? a + /?2 = 1, we obtain
Arthritis and Periodontitis: An Association Debated for Over Two Centuries.
da Silva, Andre P B; Bissada, Nabil F
2016-01-01
The chronic diseases, rheumatoid arthritis (RA) and periodontal disease (PD) lead to confined destruction of soft and hard tissues as a result of inflammatory processes. Their pathogenesis is dictated by a network of inflammatory cells and its mediators. They also share some etiological risk factors and therapeutic alternatives. The evolution of focal infection theory is summarized in this review, with special reference to PD and its relationship to RA. Foci of chronic infections exist in the oral cavity and may result in anatomically distant disease in certain individuals. Recent cumulative evidences document the influence of inflammatory diseases such as RA on the development of PD. Historical evidences and new theories on the interrelationship between the two diseases have the potential to identify novel mechanisms and therapy to improve patient outcomes. This review focuses on not only the association of focal infection theory and RA, but also on the reciprocal effects of RA and PD.
Metastasizing Esthesioneuroblastoma in a Dog.
Siudak, K; Klingler, M; Schmidt, M J; Herden, C
2015-07-01
A 7-year-old Afghan hound presented with a history of disorientation, loss of vision, and seizures. Magnetic resonance imaging helped identify a mass at the level of the main olfactory bulb that compressed and displaced adjacent tissues in the cribriform plate into the nasal cavity and nasopharynx. Bony structures were osteolytic. After removing almost 80% of the mass, the tumor recurred a few months later. Due to severe respiratory distress and subsequent to an ultrasound diagnosis of a liver tumor, the dog was euthanized. In addition to the nasal mass, a single nodule in the liver and multiple nodules in the lung were present. All masses had similar cell morphology and were diagnosed as metastasizing esthesioneuroblastoma. The neoplastic cells expressed neuron-specific enolase and chromogranin A, and a few cells within the nasal mass were positive for cytokeratin. This is the first description of a canine esthesioneuroblastoma with distant metastases. © The Author(s) 2014.
Anomalies of the systemic venous return: a review.
Mazzucco, A; Bortolotti, U; Stellin, G; Gallucci, V
1990-06-01
Congenital anomalies of the systemic venous connection to the heart represent a rather wide and heterogeneous group of malformations, whose physiological consequences may vary from nil to the most severe form of systemic arterial desaturation. The malformations may be summarized as follows: (1) Left superior vena cava connected to the coronary sinus, interrupted inferior vena cava and absent right superior vena cava that do not indicate surgical repair 'per se', but require some technical attention during open heart surgery performed for other anomalies; (2) Left superior vena cava connected to the left atrium, due to incorporation of the coronary sinus into the left atrial cavity, resulting in a right-to-left-shunt; (3) Right superior vena cava or inferior vena cava draining into the left atrium, both are extremely rare and require treatment for the ensuing right-to-left shunt; (4) Total anomalous systemic venous connection to the left atrium, usually combined with atrial isomerism and other very complex heart malformations; (5) Cor triatriatum dexter, which has been frequently diagnosed as an anomalous venous connection for its similar hemodynamic consequences. Such anomalies are reviewed with particular respect to their surgical implications.
Love, Ryan J; Jones, Kim S
2013-12-01
Connective tissue rapidly proliferates on and around biomaterials implanted in vivo, which impairs the function of the engineered tissues, biosensors, and devices. Glucocorticoids can be utilized to suppress tissue ingrowth, but can only be used for a limited time because they nonselectively arrest cell proliferation in the local environment. The present study examined use of a prolyl-4-hydroxylase inhibitor, 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (1,4-DPCA), to suppress connective tissue ingrowth in porous PLGA discs implanted in the peritoneal cavity for 28 days. The prolyl-4-hydroxylase inhibitor was found to be effective at inhibiting collagen deposition within and on the outer surface of the disc, and also limited connective tissue ingrowth, but not to the extent of glucocorticoid inhibition. Finally, it was discovered that 1,4-DPCA suppressed Scavenger Receptor A expression on a macrophage-like cell culture, which may account for the drug's ability to limit connective tissue ingrowth in vivo. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.
County-level poverty and distant stage cancer in the United States.
Greenlee, Robert T; Howe, Holly L
2009-08-01
Late stage cancer at diagnosis increases the likelihood of cancer death. We evaluated the relation of county-level poverty with late stage cancer for 18 anatomic sites using data from the North American Association of Central Cancer Registries. Stratified analysis and logistic regression were applied to 2 million incident cancers (1997-2000) from 32 states representing 57% of the United States. For 12 sites, higher county poverty significantly increased the odds of late stage, [adjusted odds ratio (95% confidence interval) comparing highest to lowest county poverty: larynx 2.4 (1.8-3.2), oral cavity 2.2 (1.8-2.7), melanoma 2.0 (1.5-2.8), female breast 1.9 (1.7-2.2), prostate 1.7 (1.5-1.9), corpus uteri 1.6 (1.3-1.9), cervix 1.6 (1.3-2.1), bladder 1.6 (1.2-2.1), colorectum 1.4 (1.3-1.5), esophagus 1.3 (1.1-1.7), stomach 1.3 (1.1-1.5), and kidney 1.3 (1.1-1.5)]. With some exceptions, county poverty associations with stage were comparable across gender and race, but stronger among metropolitan cases. A few differences by age may reflect screening patterns. In this large population-based study, higher county poverty independently predicted distant stage cancer. This held for several non-screenable cancers, suggesting improved area economic deprivation, including access to and utilization of good medical care might facilitate earlier diagnosis and longer survival even for cancers without practical screening approaches.
Glacier surge mechanism based on linked cavity configuration of the basal water conduit system
NASA Astrophysics Data System (ADS)
Kamb, Barclay
1987-08-01
Based on observations of the 1982-1983 surge of Variegated Glacier, Alaska, a model of the surge mechanism is developed in terms of a transition from the normal tunnel configuration of the basal water conduit system to a linked cavity configuration that tends to restrict the flow of water, resulting in increased basal water pressures that cause rapid basal sliding. The linked cavity system consists of basal cavities formed by ice-bedrock separation (cavitation), ˜1 m high and ˜10 m in horizontal dimensions, widely scattered over the glacier bed, and hydraulically linked by narrow connections where separation is minimal (separation gap ≲ 0.1 m). The narrow connections, called orifices, control the water flow through the conduit system; by throttling the flow through the large cavities, the orifices keep the water flux transmitted by the basal water system at normal levels even though the total cavity cross-sectional area (˜200 m2) is much larger than that of a tunnel system (˜10 m2). A physical model of the linked cavity system is formulated in terms of the dimensions of the "typical" cavity and orifice and the numbers of these across the glacier width. The model concentrates on the detailed configuration of the typical orifice and its response to basal water pressure and basal sliding, which determines the water flux carried by the system under given conditions. Configurations are worked out for two idealized orifice types, step orifices that form in the lee of downglacier-facing bedrock steps, and wave orifices that form on the lee slopes of quasisinusoidal bedrock waves and are similar to transverse "N channels." The orifice configurations are obtained from the results of solutions of the basal-sliding-with-separation problem for an ice mass constituting of linear half-space of linear rheology, with nonlinearity introduced by making the viscosity stress-dependent on an intuitive basis. Modification of the orifice shapes by melting of the ice roof due to viscous heat dissipation in the flow of water through the orifices is treated in detail under the assumption of local heat transfer, which guarantees that the heating effects are not underestimated. This treatment brings to light a melting-stability parameter Ξ that provides a measure of the influence of viscous heating on orifice cavitation, similar but distinct for step and wave orifices. Orifice shapes and the amounts of roof meltback are determined by Ξ. When Ξ ≳ 1, so that the system is "viscous-heating-dominated," the orifices are unstable against rapid growth in response to a modest increase in water pressure or in orifice size over their steady state values. This growth instability is somewhat similar to the jökulhlaup-type instability of tunnels, which are likewise heating-dominated. When Ξ ≲ 1, the orifices are stable against perturbations of modest to even large size. Stabilization is promoted by high sliding velocity ν, expressed in terms of a ν-½ and ν-1 dependence of Ξ for step and wave cavities. The relationships between basal water pressure and water flux transmitted by linked cavity models of step and wave orifice type are calculated for an empirical relation between water pressure and sliding velocity and for a particular, reasonable choice of system parameters. In all cases the flux is an increasing function of the water pressure, in contrast to the inverse flux-versus-pressure relation for tunnels. In consequence, a linked cavity system can exist stably as a system of many interconnected conduits distributed across the glacier bed, in contrast to a tunnel system, which must condense to one or at most a few main tunnels. The linked cavity model gives basal water pressures much higher than the tunnel model at water fluxes ≳1 m3/s if the bed roughness features that generate the orifices have step heights or wave amplitudes less than about 0.1 m. The calculated basal water pressure of the particular linked cavity models evaluated is about 2 to 5 bars below ice overburden pressure for water fluxes in the range from about 2 to 20 m3/s, which matches reasonably the observed conditions in Variegated Glacier in surge; in contrast, the calculated water pressure for a single-tunnel model is about 14 to 17 bars below overburden over the same flux range. The contrast in water pressures for the two types of basal conduit system furnishes the basis for a surge mechanism involving transition from a tunnel system at low pressure to a linked cavity system at high pressure. The parameter Ξ is about 0.2 for the linked cavity models evaluated, meaning that they are stable but that a modest change in system parameters could produce instability. Unstable orifice growth results in the generation of tunnel segments, which may connect up in a cooperative fashion, leading to conversion of the linked cavity system to a tunnel system, with large decrease in water pressure and sliding velocity. This is what probably happens in surge termination. Glaciers for which Ξ ≲ 1 can go into surge, while those for which Ξ ≳ 1 cannot. Because Ξ varies as α3/2 (where α is surface slope), low values of Ξ are more probable for glaciers of low slope, and because slope correlates inversely with glacier length in general, the model predicts a direct correlation between glacier length and probability of surging; such a correlation is observed (Clarke et al., 1986). Because Ξ varies inversely with the basal shear stress τ, the increase of τ that takes place in the reservoir area in the buildup between surges causes a decrease in Ξ there, which, by reducing Ξ below the critical value ˜1, can allow surge initiation and the start of a new surge cycle. Transition to a linked cavity system without tunnels should occur spontaneously at low enough water flux, in agreement with observed surge initiation in winter.
High-performance coaxial EPR cavity for investigations at elevated temperatures and pressures
NASA Astrophysics Data System (ADS)
Goldberg, Ira B.; McKinney, Ted M.
1984-07-01
A microwave cavity suitable for heating a sample to temperatures above 800 °C within 15 s at gas pressures above 17.5 MPa is reported. The cavity is coaxial and operates in the TE011 mode at frequencies between 9 and 10 GHz. The heating element is constructed of nickel-chromium (i.e., Chromel) wire. It consists of two concentric helices wound in opposite senses (directions) and connected in series so as to minimize the magnetic field generated by the heater current. The heater is potted in magnesium oxide-phosphate ceramic and placed inside of a cylinder made from 50-μm copper foil which provides uniform temperature distribution and shields the heater from the microwave field. This assembly then serves as the heating element and the coaxial conductor of the cavity. The diameter of the coaxial heater assembly is approximately 7 mm. The sample is confined by a cylindrical quartz cuvette which surrounds the coaxial conductor. Sample thicknesses of 0.2 to 1.0 mm can be used. Heating from room temperature to 800 °C requires between 15 and 20 s. Operating pressures up to 17 MPa have been used, although the structural design limit of the brass or beryllium copper walls is greater than 22 MPa. Modulation coils are placed in recessed areas of the cavity walls and covered with a thin layer of copper. Cooling water flows through channels cut into the walls to maintain constant microwave parameters. Q factors of 8000 -12 000 can be obtained depending on the sample.
Measurement of the Dielectric Constant of Seawater at L-Band: Techniques and Measurements
NASA Technical Reports Server (NTRS)
Lang, R.; Utku, C.; Tarkocin, Y.; LeVine, D.
2009-01-01
Satellite instruments, that will monitor salinity from space in the near future, require an accurate relationship between salinity/temperature and seawater dielectric constant. This paper will review measurements that were made of the dielectric constant of seawater during the past several years. The objective of the measurements is to determine the dependence of the dielectric constant of seawater on salinity and on temperature, more accurately than in the past. by taking advantage of modem instrumentation. The measurements of seawater permittivity have been performed as a function of salinity and temperature using a transmission resonant cavity technique. The measurements have been made in the salinity range of 10 to 38 psu and in the temperature range of IOU C to 35 C. These results will be useful in algorithm development for sensor systems such as SMOS and Aquarius. The measurement system consists of a brass microwave cavity that is resonant at 1.413 GHz. The seawater is introduced into the cavity through a capillary glass tube having an inner diameter of 0.1 mm. The diameter of the tube has been made very small so that the amount of seawater introduced in the cavity is small - thus maintaining the sensitivity of the measurements and allowing the use of perturbation theory predicting the seawater permittivity. The change in resonant frequency and the change in cavity Q can be used to determine the real and imaginary pare of the dielectric constant of seawater introduced into the slender tube. The microwave measurements are made by an HPS722D network analyzer. The cavity has been immersed in a uateriethylene-glycol bath which is connected to a Lauda circulator. The circulator keeps the brass cavity at a temperature constant to within 0.01 degrees. The system is automated using a Visual Basic program to control the analyzer and to collect the data. The results of the dielectric constant measurements of seawater will be presented. The measurement results will be compared with permittivity values generated from the Kline and Swift relationship. Two methods of calibration will be discussed, The errors that each technique introduces into the measurement resulls will be reviewed. Temperature stability, frequency drift and the effect of increasing cavity transmission loss on the unloaded cavity Q will also be discussed.
Shobharani, M; Viraktamath, C A; Webb, M D
2018-01-02
Species of the leafhopper genus Penthimia Germar known from the Indian subcontinent are reviewed based on the examination of type specimens. Seven new species of the genus, Penthimia curvata sp. nov. (Karnataka: Bandipur), P. meghalayensis sp. nov. (Meghalaya: Nangpoh), P. neoattenuata sp. nov. (India: Tamil Nadu), P. ribhoi sp. nov. (India: Meghalaya), P. sahyadrica sp. nov. (Karnataka: Dharmasthala, Agumbe; Kerala: Thekkady), P. spiculata sp. nov. (Karnataka: Nagarahole) and P. tumida sp. nov. (Tamil Nadu: Ootacamund; Kerala: Munnar) are described. The following nomenclatorial changes are proposed: Penthimia alba Zahniser, McKamey Dmitriev, 2012 (replacement name for P. thoracica Distant, 1918, nec Panzer, 1799), syn. nov. of P. quadrinotata Distant, 1918; Neodartus scutellatus Distant, 1908 syn. nov. of Penthimia ereba Distant 1908; P. nilgiriensis Distant, 1918 syn. nov. of P. montana Distant, 1918; P. scutellata (Distant) comb. nov. (from genus Neodartus); a lectotype is designated for P. maculosa Distant, stat. revived, thereby removing its synonymy with P. scapularis Distant. The following other lectotypes are designated: P. attenuata Distant, P. subniger Distant, P. scapularis Distant, P. distanti Baker, P. ereba Distant, N. scutellatus Distant, P. fraterna Distant, P. funebris Distant, P. juno Distant, P. maculosa Distant, P. montana Distant, P. noctua Distant, P. quadrinotata Distant, P. alba Zahniser, McKamey Dmitriev. Examination of types of Penthimia rufopunctata Motschulsky revealed that it belongs to Penthimia and hence it is transferred back to that genus from Neodartus, revised placement. The following species previously included in the genus Penthimia are transferred to the genera Tambila Distant and Vulturnus Kirkaldy: Tambila badia (Distant) comb. nov., T. majuscula (Distant) comb. nov., T. vittatifrons (Distant) comb. nov., T. variabilis (Distant) comb. nov. and Vulturnus flavocapitata (Distant) comb. nov. Three species are treated in a new Penthimia compacta Walker complex, i.e., Penthimia compacta Walker 1851, Penthimia subniger Distant 1908 and Penthimia scapularis Distant 1908. All taxa are described and a key to Penthimiini genera found in the subcontinent and also a key to species of Penthimia are included.
Origins of coevolution between residues distant in protein 3D structures
Ovchinnikov, Sergey; Kamisetty, Hetunandan; Baker, David
2017-01-01
Residue pairs that directly coevolve in protein families are generally close in protein 3D structures. Here we study the exceptions to this general trend—directly coevolving residue pairs that are distant in protein structures—to determine the origins of evolutionary pressure on spatially distant residues and to understand the sources of error in contact-based structure prediction. Over a set of 4,000 protein families, we find that 25% of directly coevolving residue pairs are separated by more than 5 Å in protein structures and 3% by more than 15 Å. The majority (91%) of directly coevolving residue pairs in the 5–15 Å range are found to be in contact in at least one homologous structure—these exceptions arise from structural variation in the family in the region containing the residues. Thirty-five percent of the exceptions greater than 15 Å are at homo-oligomeric interfaces, 19% arise from family structural variation, and 27% are in repeat proteins likely reflecting alignment errors. Of the remaining long-range exceptions (<1% of the total number of coupled pairs), many can be attributed to close interactions in an oligomeric state. Overall, the results suggest that directly coevolving residue pairs not in repeat proteins are spatially proximal in at least one biologically relevant protein conformation within the family; we find little evidence for direct coupling between residues at spatially separated allosteric and functional sites or for increased direct coupling between residue pairs on putative allosteric pathways connecting them. PMID:28784799
Improving the accuracy of macromolecular structure refinement at 7 Å resolution.
Brunger, Axel T; Adams, Paul D; Fromme, Petra; Fromme, Raimund; Levitt, Michael; Schröder, Gunnar F
2012-06-06
In X-ray crystallography, molecular replacement and subsequent refinement is challenging at low resolution. We compared refinement methods using synchrotron diffraction data of photosystem I at 7.4 Å resolution, starting from different initial models with increasing deviations from the known high-resolution structure. Standard refinement spoiled the initial models, moving them further away from the true structure and leading to high R(free)-values. In contrast, DEN refinement improved even the most distant starting model as judged by R(free), atomic root-mean-square differences to the true structure, significance of features not included in the initial model, and connectivity of electron density. The best protocol was DEN refinement with initial segmented rigid-body refinement. For the most distant initial model, the fraction of atoms within 2 Å of the true structure improved from 24% to 60%. We also found a significant correlation between R(free) values and the accuracy of the model, suggesting that R(free) is useful even at low resolution. Copyright © 2012 Elsevier Ltd. All rights reserved.
Boutayeb, Alaae; Marmade, Lahcen; Bensouda, Adil; Moughil, Said
2012-01-01
The left superior vena cava is the most common congenital venous anomaly in the chest; however, its drainage into the left atrium is exceptional. The aim of the paper is to describe our novel technique to connect the left superior vena cava to the right cavities using the left atrial appendage, without cardiopulmonary bypass. PMID:22802356
Room temperature acoustic transducers for high-temperature thermometry
NASA Astrophysics Data System (ADS)
Ripple, D. C.; Murdock, W. E.; Strouse, G. F.; Gillis, K. A.; Moldover, M. R.
2013-09-01
We have successfully conducted highly-accurate, primary acoustic thermometry at 600 K using a sound source and a sound detector located outside the thermostat, at room temperature. We describe the source, the detector, and the ducts that connected them to our cavity resonator. This transducer system preserved the purity of the argon gas, generated small, predictable perturbations to the acoustic resonance frequencies, and can be used well above 600 K.
Integrated head package cable carrier for a nuclear power plant
Meuschke, Robert E.; Trombola, Daniel M.
1995-01-01
A cabling arrangement is provided for a nuclear reactor located within a containment. Structure inside the containment is characterized by a wall having a near side surrounding the reactor vessel defining a cavity, an operating deck outside the cavity, a sub-space below the deck and on a far side of the wall spaced from the near side, and an operating area above the deck. The arrangement includes a movable frame supporting a plurality of cables extending through the frame, each connectable at a first end to a head package on the reactor vessel and each having a second end located in the sub-space. The frame is movable, with the cables, between a first position during normal operation of the reactor when the cables are connected to the head package, located outside the sub-space proximate the head package, and a second position during refueling when the cables are disconnected from the head package, located in the sub-space. In a preferred embodiment, the frame straddles the top of the wall in a substantially horizontal orientation in the first position, pivots about an end distal from the head package to a substantially vertically oriented intermediate position, and is guided, while remaining about vertically oriented, along a track in the sub-space to the second position.
Predictive protocol of flocks with small-world connection pattern.
Zhang, Hai-Tao; Chen, Michael Z Q; Zhou, Tao
2009-01-01
By introducing a predictive mechanism with small-world connections, we propose a new motion protocol for self-driven flocks. The small-world connections are implemented by randomly adding long-range interactions from the leader to a few distant agents, namely, pseudoleaders. The leader can directly affect the pseudoleaders, thereby influencing all the other agents through them efficiently. Moreover, these pseudoleaders are able to predict the leader's motion several steps ahead and use this information in decision making towards coherent flocking with more stable formation. It is shown that drastic improvement can be achieved in terms of both the consensus performance and the communication cost. From the engineering point of view, the current protocol allows for a significant improvement in the cohesion and rigidity of the formation at a fairly low cost of adding a few long-range links embedded with predictive capabilities. Significantly, this work uncovers an important feature of flocks that predictive capability and long-range links can compensate for the insufficiency of each other. These conclusions are valid for both the attractive and repulsive swarm model and the Vicsek model.
Optical control of spin-dependent thermal transport in a quantum ring
NASA Astrophysics Data System (ADS)
Abdullah, Nzar Rauf
2018-05-01
We report on calculation of spin-dependent thermal transport through a quantum ring with the Rashba spin-orbit interaction. The quantum ring is connected to two electron reservoirs with different temperatures. Tuning the Rashba coupling constant, degenerate energy states are formed leading to a suppression of the heat and thermoelectric currents. In addition, the quantum ring is coupled to a photon cavity with a single photon mode and linearly polarized photon field. In a resonance regime, when the photon energy is approximately equal to the energy spacing between two lowest degenerate states of the ring, the polarized photon field can significantly control the heat and thermoelectric currents in the system. The roles of the number of photon initially in the cavity, and electron-photon coupling strength on spin-dependent heat and thermoelectric currents are presented.
Air riding seal with purge cavity
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sexton, Thomas D; Mills, Jacob A
An air riding seal for a turbine in a gas turbine engine, where an annular piston is axial moveable within an annular piston chamber formed in a stator of the turbine and forms a seal with a surface on the rotor using pressurized air that forms a cushion in a pocket of the annular piston. A purge cavity is formed on the annular piston and is connected to a purge hole that extends through the annular piston to a lower pressure region around the annular piston or through the rotor to an opposite side. The annular piston is sealed alsomore » with inner and outer seals that can be a labyrinth seal to form an additional seal than the cushion of air in the pocket to prevent the face of the air riding seal from overheating.« less
Dynamic Metasurface Aperture as Smart Around-the-Corner Motion Detector.
Del Hougne, Philipp; F Imani, Mohammadreza; Sleasman, Timothy; Gollub, Jonah N; Fink, Mathias; Lerosey, Geoffroy; Smith, David R
2018-04-25
Detecting and analysing motion is a key feature of Smart Homes and the connected sensor vision they embrace. At present, most motion sensors operate in line-of-sight Doppler shift schemes. Here, we propose an alternative approach suitable for indoor environments, which effectively constitute disordered cavities for radio frequency (RF) waves; we exploit the fundamental sensitivity of modes of such cavities to perturbations, caused here by moving objects. We establish experimentally three key features of our proposed system: (i) ability to capture the temporal variations of motion and discern information such as periodicity ("smart"), (ii) non line-of-sight motion detection, and (iii) single-frequency operation. Moreover, we explain theoretically and demonstrate experimentally that the use of dynamic metasurface apertures can substantially enhance the performance of RF motion detection. Potential applications include accurately detecting human presence and monitoring inhabitants' vital signs.
PIP-II Cryogenic System and the evolution of Superfluid Helium Cryogenic Plant Specifications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chakravarty, Anindya; Rane, Tejas; Klebaner, Arkadiy
2017-07-06
The PIP-II cryogenic system consists of a Superfluid Helium Cryogenic Plant (SHCP) and a Cryogenic Distribution System (CDS) connecting the SHCP to the Superconducting (SC) Linac consisting of 25 cryomodules. The dynamic heat load of the SC cavities for continuous wave (CW) as well as pulsed mode of operation has been listed out. The static heat loads of the cavities along with the CDS have also been discussed. Simulation study has been carried out to compute the supercritical helium (SHe) flow requirements for each cryomodule. Comparison between the flow requirements of the cryomodules for the CW and pulsed modes ofmore » operation have also been made. From the total computed heat load and pressure drop values in the CDS, the basic specifications for the SHCP, required for cooling the SC Linac, have evolved.« less
[PREVENTION AND CORRECTION OF PULMONARY COMPLICATIONS FOR SEVERE ACUTE PANCREATITIS].
Fedorkiv, M B
2015-06-01
Increased of proinflammatory cytokines levels, including interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-alpha) on severe acute pancreatitis causes vasodilatation, increased permeability of the wall, accumulation of fluid in lung tissue and pleural sinuses. Transudate from acute parapancreatyc clusters of hot liquid and abdomen falls into the chest cavity through microscopic defects in the diaphragm due to the formation of pathological pleural-peritoneal connections or the relevant pressure gradient between the abdominal and pleural cavities. Remediation and removal of acute parapancreatyc clusters combined with the use of a multicomponent drug infusion therapy Cytoflavin provide a reduction in the frequency of pulmonary complications of acute pancreatitis from 48.3 to 31.0%. Use of the drug Cytoflavin reduces the severity of endogenous intoxication and mortality from acute lung injury from 12.9 to 6.1%.
Perfect absorption in 1D photonic crystal nanobeam embedded with graphene/Al2O3 multilayer stack
NASA Astrophysics Data System (ADS)
Liu, Hanqing; Zha, Song; Liu, Peiguo; Zhou, Xiaotian; Bian, Li-an
2018-05-01
We exploit the concept of critical coupling to graphene based chip-integrated applications and numerically demonstrate that a perfect absorption (PA) absorber in the near-infrared can be obtained by graphene/Al2O3 multilayer stack (GAMS) critical coupling with a resonant cavity in the 1D photonic crystal nanobeam (PCN). The key point is dynamically matching the coupling rate of incident light wave to the cavity with the absorbing rate of GAMS via electrically modulating the chemical potential of graphene. Simulation results show that the radius of GAMS as well as the thickness of Al2O3 layer are closely connected with the performance of perfect absorption. These results may provide potential applications in the high-density integrated optical devices, photolectric transducers, and laser pulse limiters.
Glycosaminoglycans and fibrillar collagen in Priapulida: a histo- and cytochemical study.
Welsch, U; Erlinger, R; Storch, V
1992-12-01
The distribution of glycosaminoglycans and fibrillar collagen was studied in various tissues of priapulids, which represent an ancient group of marine metazoa. Sulphated glycosaminoglycans, as demonstrated at the electron microscopical level by Cupromeronic blue, were predominantly found in the cuticle, in basement membranes and also in the narrow connective tissue space below epidermis and anterior intestine. On the basis of their morphology the Cupromeronic blue precipitates could be divided into several groups. Fibrillar collagen occurred in the connective tissue under the epidermis and the epithelium of the anterior intestine. The spatial interrelationship between fibrillar collagen and glycosaminoglycans lacked with some exceptions, the high regularity found in connective tissues of other invertebrates and of vertebrates. This might be related to the special skeletal system of priapulids, consisting mainly of a strong extracellular cuticle and the turgor of the fluid-filled body cavity. In such a system the usual supportive structures seem to be of less functional significance.
Has the connection between polyploidy and diversification actually been tested?
Kellogg, Elizabeth A
2016-04-01
Many major clades of angiosperms have several whole genome duplications (polyploidization events) in their distant past, suggesting that polyploidy drives or at least permits diversification. However, data on recently diverged groups are more equivocal, finding little evidence of elevated diversification following polyploidy. The discrepancy may be attributable at least in part to methodology. Many studies use indirect methods, such as chromosome numbers, genome size, and Ks plots, to test polyploidy, although these approaches can be misleading, and often lack sufficient resolution. A direct test of diversification following polyploidy requires a sequence-based approach that traces the history of nuclear genomes rather than species. These methods identify the point of coalescence of ancestral genomes, but may be misleading about the time and thus the extent of diversification. Limitations of existing methods mean that the connection between polyploidy and diversification has not been rigorously tested and remains unknown. Copyright © 2016 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Orange, N. Brice; Chesny, David L.; Gendre, Bruce
Solar variability investigations that include magnetic energy coupling are paramount to solving many key solar/stellar physics problems, particularly for understanding the temporal variability of magnetic energy redistribution and heating processes. Using three years of observations from the Solar Dynamics Observatory ’ s Atmospheric Imaging Assembly and Heliosemic Magnetic Imager, we measured radiative and magnetic fluxes from gross features and at full-disk scales, respectively. Magnetic energy coupling analyses support radiative flux descriptions via the plasma heating connectivity of dominant (magnetic) and diffuse components, specifically of the predominantly closed-field corona. Our work shows that this relationship favors an energetic redistribution efficiency acrossmore » large temperature gradients, and potentially sheds light on the long-standing issue of diffuse unresolved low corona emission. The close connection between magnetic energy redistribution and plasma conditions revealed by this work lends significant insight into the field of stellar physics, as we have provided possible means for probing distant sources in currently limited and/or undetectable radiation distributions.« less
Glial heterotopia of the lip: A rare presentation.
Dadaci, Mehmet; Bayram, Fazli Cengiz; Ince, Bilsev; Bilgen, Fatma
2016-01-01
Glial heterotopia represents collections of normal glial tissue in an abnormal location distant to the central nervous system or spinal canal with no intracranial connectivity. Nasal gliomas are non-neoplastic midline tumours, with limited growth potential and no similarity to the central nervous system gliomas. The nose and the nasopharynx are the most common sites of location. Existence of glial heterotopia in the lip region is a rare developmental disorder. We report a case of large glial heterotopia in the upper lip region in a full-term female newborn which had intracranial extension with a fibrotic band. After the surgery, there was no recurrence in the follow-up period of 3 years. When glial heterotopia, which is a rare midline anomaly, is suspected, possible intracranial connection and properties of the mass should be evaluated by magnetic resonance imaging. By this way, lower complication rate and better aesthetic results can be achieved with early diagnosis and proper surgery.
Evolution and development of brain networks: from Caenorhabditis elegans to Homo sapiens.
Kaiser, Marcus; Varier, Sreedevi
2011-01-01
Neural networks show a progressive increase in complexity during the time course of evolution. From diffuse nerve nets in Cnidaria to modular, hierarchical systems in macaque and humans, there is a gradual shift from simple processes involving a limited amount of tasks and modalities to complex functional and behavioral processing integrating different kinds of information from highly specialized tissue. However, studies in a range of species suggest that fundamental similarities, in spatial and topological features as well as in developmental mechanisms for network formation, are retained across evolution. 'Small-world' topology and highly connected regions (hubs) are prevalent across the evolutionary scale, ensuring efficient processing and resilience to internal (e.g. lesions) and external (e.g. environment) changes. Furthermore, in most species, even the establishment of hubs, long-range connections linking distant components, and a modular organization, relies on similar mechanisms. In conclusion, evolutionary divergence leads to greater complexity while following essential developmental constraints.
Noise propagation effects in power supply distribution systems for high-energy physics experiments
NASA Astrophysics Data System (ADS)
Arteche, F.; Rivetta, C.; Iglesias, M.; Echeverria, I.; Pradas, A.; Arcega, F. J.
2017-12-01
High-energy physics experiments are supplied by thousands of power supply units placed in distant areas from the front-end electronics. The power supply units and the front-end electronics are connected through long power cables that propagate the output noise from the power supplies to the detector. This paper addresses the effect of long cables on the noise propagation and the impact that those cables have on the conducted emission levels required for the power supplies and the selection of EMI filters for the front-end electronic low-voltage input. This analysis is part of the electromagnetic compatibility based design focused on functional safety to define the type of cable, shield connections, EMI filters and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.
Noise propagation effects in power supply distribution systems for high-energy physics experiments
Arteche, F.; Rivetta, C.; Iglesias, M.; ...
2017-12-05
High-energy physics experiments are supplied by thousands of power supply units placed in distant areas from the front-end electronics. The power supply units and the front-end electronics are connected through long power cables that propagate the output noise from the power supplies to the detector. Here, this paper addresses the effect of long cables on the noise propagation and the impact that those cables have on the conducted emission levels required for the power supplies and the selection of EMI filters for the front-end electronic low-voltage input. Lastly, this analysis is part of the electromagnetic compatibility based design focused onmore » functional safety to define the type of cable, shield connections, EMI filters and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.« less
Noise propagation effects in power supply distribution systems for high-energy physics experiments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Arteche, F.; Rivetta, C.; Iglesias, M.
High-energy physics experiments are supplied by thousands of power supply units placed in distant areas from the front-end electronics. The power supply units and the front-end electronics are connected through long power cables that propagate the output noise from the power supplies to the detector. Here, this paper addresses the effect of long cables on the noise propagation and the impact that those cables have on the conducted emission levels required for the power supplies and the selection of EMI filters for the front-end electronic low-voltage input. Lastly, this analysis is part of the electromagnetic compatibility based design focused onmore » functional safety to define the type of cable, shield connections, EMI filters and power supply specifications required to ensure the successful integration of the detector and, specifically, to achieve the designed performance of the front-end electronics.« less
Remote creation of hybrid entanglement between particle-like and wave-like optical qubits
NASA Astrophysics Data System (ADS)
Morin, Olivier; Huang, Kun; Liu, Jianli; Le Jeannic, Hanna; Fabre, Claude; Laurat, Julien
2014-07-01
The wave-particle duality of light has led to two different encodings for optical quantum information processing. Several approaches have emerged based either on particle-like discrete-variable states (that is, finite-dimensional quantum systems) or on wave-like continuous-variable states (that is, infinite-dimensional systems). Here, we demonstrate the generation of entanglement between optical qubits of these different types, located at distant places and connected by a lossy channel. Such hybrid entanglement, which is a key resource for a variety of recently proposed schemes, including quantum cryptography and computing, enables information to be converted from one Hilbert space to the other via teleportation and therefore the connection of remote quantum processors based upon different encodings. Beyond its fundamental significance for the exploration of entanglement and its possible instantiations, our optical circuit holds promise for implementations of heterogeneous network, where discrete- and continuous-variable operations and techniques can be efficiently combined.
Wenner, Jennifer A.; Burch, Melissa M.; Lynch, Julie S.; Bauer, Patricia J.
2008-01-01
Previous research has revealed a connection between the contributions parents make while reminiscing and their children’s narratives for personally experienced events. The present research expands the literature by focusing on the connection between parental reminiscing and children’s production of fictional narratives. Four- to 9-year-olds and their parents reminisced about past shared events and then, with an experimenter, the children produced narratives based on wordless picture books. The results revealed that the overall quality of the fictional narratives was correlated with parents’ provision statements that emphasized orientation and evaluation in the reminiscence narrative. For younger children, correlations held for reminiscence narratives about recent events. For older children, correlations held for reminiscence narratives about events from the distant past. The results are consistent with the suggestion that children learn general storytelling skills from adult models. PMID:18062986
"What we need is a crop ecologist": ecology and agricultural science in Progressive-era America.
Hersey, Mark D
2011-01-01
Though they are often seen as foils for each other, ecology and agricultural science co-evolved. With shared roots in late nineteenth-century botany, ecologists and agronomists fostered important connections during the Progressive era that have been largely overlooked despite a number of finely nuanced studies of ecology's origins. But if 'applied ecology' once effectively meant agriculture, over the course of the first decades of the twentieth century the relationship between ecology and scientific agriculture grew strained. Agriculturists narrowed their focus to increasing yields, and ecologists sought to establish their discipline as a distant theoretical science and so distanced themselves from its agricultural applications. By the end of World War I, the process of disciplinary specialization was well underway. In time, the two disciplines diverged so completely that the once vital connections between them were obscured and forgotten.
Elucidating the nature and mechanism of tic improvement in tourette syndrome: a pilot study.
Shprecher, David R; Gannon, Keenan; Agarwal, Nivedita; Shi, Xianfeng; Anderson, Jeffrey S
2014-01-01
For unclear reasons, many Tourette syndrome (TS) children report near-complete tic remission by young adulthood. Immature maturation of brain networks, observed with resting-state functional MRI (rs-fc-MRI) in adolescents and adults with TS, might evolve to a mature pattern in adults who experience tic improvement or remission. We explored the feasibility of testing this hypothesis in our population of young adult TS males, each with prior clinical assessments completed during childhood as part of a separate TS Association Genetics Consortium study. A total of 10 TS males (off tic suppressing drugs for at least 6 months) aged 19-32 years, mean follow-up interval 7.5 (2 to 13) years, and 11 neurologically normal controls were enrolled and underwent 3-Tesla structural and rs-fc-MRI sequences. The mean change in Yale Global Tic Severity Scale (YGTSS) was -31.5% (total) and -26.6% (YGTSS motor+vocal). Two subjects reported resolution of tic-related disability, with drops from mean 45 to 16.5 (YGTSS-total) and 25 to 11.5 (YGTSS motor+vocal.). Rs-fc-MRI revealed significantly increased connectivity between the ipsilateral anterior and mid cingulate cortex and striatum, increased connectivity between local connections, and decreased connectivity between more distant connections; representing an immature connectivity pattern. Similar to previous reports, we found immature patterns of functional connectivity in adult TS subjects. Despite a lack of complete tic remission, two subjects exhibited dramatic drops in tic severity that correlated with tic-related disability improvement. More work is needed to elucidate the mechanism of such dramatic improvement in TS.
Jeffs, Janelle; Ichida, Jennifer M.; Federer, Frederick
2009-01-01
In primates, a split of the horizontal meridian (HM) representation at the V2 rostral border divides this area into dorsal (V2d) and ventral (V2v) halves (representing lower and upper visual quadrants, respectively), causing retinotopically neighboring loci across the HM to be distant within V2. How is perceptual continuity maintained across this discontinuous HM representation? Injections of neuroanatomical tracers in marmoset V2d demonstrated that cells near the V2d rostral border can maintain retinotopic continuity within their classical and extra-classical receptive field (RF), by making both local and long-range intra- and interareal connections with ventral cortex representing the upper visual quadrant. V2d neurons located <0.9–1.3 mm from the V2d rostral border, whose RFs presumably do not cross the HM, make nonretinotopic horizontal connections with V2v neurons in the supra- and infragranular layers. V2d neurons located <0.6–0.9 mm from the border, whose RFs presumably cross the HM, in addition make retinotopic local connections with V2v neurons in layer 4. V2d neurons also make interareal connections with upper visual field regions of extrastriate cortex, but not of MT or MTc outside the foveal representation. Labeled connections in ventral cortex appear to represent the “missing” portion of the connectional fields in V2d across the HM. We conclude that connections between dorsal and ventral cortex can create visual field continuity within a second-order discontinuous visual topography. PMID:18755777
Diversity in primary palate ontogeny of amniotes revealed with 3D imaging
Abramyan, John; Thivichon-Prince, Beatrice; Richman, Joy Marion
2015-01-01
The amniote primary palate encompasses the upper lip and the nasal cavities. During embryonic development, the primary palate forms from the fusion of the maxillary, medial nasal and lateral nasal prominences. In mammals, as the primary palate fuses, the nasal and oral cavities become completely separated. Subsequently, the tissue demarcating the future internal nares (choanae) thins and becomes the bucconasal membrane, which eventually ruptures and allows for the essential connection of the oral and nasal cavities to form. In reptiles (including birds), the other major amniote group, primary palate ontogeny is poorly studied with respect to prominence fusion, especially the formation of a bucconasal membrane. Using 3D optical projection tomography, we found that the prominences that initiate primary palate formation are similar between mammals and crocodilians but distinct from turtles and lizards, which are in turn similar to each other. Chickens are distinct from all non-avian lineages and instead resemble human embryos in this aspect. The majority of reptiles maintain a communication between the oral and nasal cavities via the choanae during primary palate formation. However, crocodiles appear to have a transient separation between the oral and nasal cavities. Furthermore, the three lizard species examined here, exhibit temporary closure of their external nares via fusion of the lateral nasal prominences with the frontonasal mass, subsequently reopening them just before hatching. The mechanism of the persistent choanal opening was examined in chicken embryos. The mesenchyme posterior/dorsal to the choana had a significant decline in proliferation index, whereas the mesenchyme of the facial processes remained high. This differential proliferation allows the choana to form a channel between the oral and nasal cavities as the facial prominences grow and fuse around it. Our data show that primary palate ontogeny has been modified extensively to support the array of morphological diversity that has evolved among amniotes. PMID:25904546
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eddy, N.; Fellenz, B.; Prieto, P.
The first cryomodule for the beam test facility at the Fermilab New-Muon-Lab building is currently under RF commissioning. Among other diagnostics systems, the transverse position of the helium gas return pipe with the connected 1.3 GHz SRF accelerating cavities is measured along the {approx}15 m long module using a stretched-wire position monitoring system. An overview of the wire position monitor system technology is given, along with preliminary results taken at the initial module cooldown, and during further testing. As the measurement system offers a high resolution, we also discuss options for use as a vibration detector. An electron beam testmore » facility, based on superconducting RF (SRF) TESLA-style cryomodules is currently under construction at the Fermilab New-Muon-Lab (NML) building. The first, so-called type III+, cryomodule (CM-1), equipped with eight 1.3 GHz nine-cell accelerating cavities was recently cooled down to 2 K, and is currently under RF conditioning. The transverse alignment of the cavity string within the cryomodule is crucial for minimizing transverse kick and beam break-up effects, generated by the high-order dipole modes of misaligned accelerating structures. An optimum alignment can only be guaranteed during the assembly of the cavity string, i.e. at room temperatures. The final position of the cavities after cooldown is uncontrollable, and therefore unknown. A wire position monitoring system (WPM) can help to understand the transverse motion of the cavities during cooldown, their final location and the long term position stability after cryo-temperatures are settled, as well as the position reproducibility for several cold-warm cycles. It also may serve as vibration sensor, as the wire acts as a high-Q resonant detector for mechanical vibrations in the low-audio frequency range. The WPM system consists out of a stretched-wire position detection system, provided with help of INFN-Milano and DESY Hamburg, and RF generation and read-out electronics, developed at Fermilab.« less
NASA Astrophysics Data System (ADS)
Cartar, William K.
Photonic crystal microcavity quantum dot lasers show promise as high quality-factor, low threshold lasers, that can be integrated on-chip, with tunable room temperature opera- tions. However, such semiconductor microcavity lasers are notoriously difficult to model in a self-consistent way and are primarily modelled by simplified rate equation approxima- tions, typically fit to experimental data, which limits investigations of their optimization and fundamental light-matter interaction processes. Moreover, simple cavity mode optical theory and rate equations have recently been shown to fail in explaining lasing threshold trends in triangular lattice photonic crystal cavities as a function of cavity size, and the potential impact of fabrication disorder is not well understood. In this thesis, we develop a simple but powerful numerical scheme for modelling the quantum dot active layer used for lasing in these photonic crystal cavity structures, as an ensemble of randomly posi- tioned artificial two-level atoms. Each two-level atom is defined by optical Bloch equations solved by a quantum master equation that includes phenomenological pure dephasing and an incoherent pump rate that effectively models a multi-level gain system. Light-matter in- teractions of both passive and lasing structures are analyzed using simulation defined tools and post-simulation Green function techniques. We implement an active layer ensemble of up to 24,000 statistically unique quantum dots in photonic crystal cavity simulations, using a self-consistent finite-difference time-domain method. This method has the distinct advantage of capturing effects such as dipole-dipole coupling and radiative decay, without the need for any phenomenological terms, since the time-domain solution self-consistently captures these effects. Our analysis demonstrates a powerful ability to connect with recent experimental trends, while remaining completely general in its set-up; for example, we do not invoke common approximations such as the rotating-wave or slowly-varying envelope approximations, and solve dynamics with zero a priori knowledge.
Xenon NMR of liquid crystals confined to cylindrical nanocavities: a simulation study.
Karjalainen, Jouni; Vaara, Juha; Straka, Michal; Lantto, Perttu
2015-03-21
Applications of liquid crystals (LCs), such as smart windows and the ubiquitous display devices, are based on controlling the orientational and translational order in a small volume of LC medium. Hence, understanding the effects of confinement to the liquid crystal phase behaviour is essential. The NMR shielding of (129)Xe atoms dissolved in LCs constitutes a very sensitive probe to the details of LC environment. Linking the experimental results to microscopic phenomena calls for molecular simulations. In this work, the NMR shielding of atomic (129)Xe dissolved in a uniaxial thermotropic LC confined to nanosized cylindrical cavities is computed from coarse-grained (CG) isobaric Monte Carlo (MC) simulations with a quantum-chemically (QC) pre-parameterised pairwise-additive model for the Xe nuclear shielding tensor. We report the results for the (129)Xe nuclear shielding and its connection to the structure and order of the LC appropriate to two different cavity sizes, as well as a comparison to the results of bulk (non-confined) simulations. We find that the confinement changes the LC phase structure dramatically and gives rise to the coexistence of varying degrees of LC order, which is reflected in the Xe shielding. Furthermore, we qualitatively reproduce the behaviour of the mean (129)Xe chemical shift with respect to temperature for atomic Xe dissolved in LC confined to controlled-pore glass materials. In the small-radius cavity the nematic - paranematic phase transition is revealed only by the anisotropic component of the (129)Xe nuclear shielding. In the larger cavity, the nematic - paranematic - isotropic transition is clearly seen in the Xe shielding. The simulated (129)Xe NMR shielding is insensitive to the smectic-A - nematic transition, since in the smectic-A phase, the Xe atoms largely occupy the imperfect layer structure near the cavity walls. The direct contribution of the cavity wall to (129)Xe nuclear shielding is dependent on the cavity size but independent of temperature. Our results show that the combination of CG simulations and a QC pre-parameterised (129)Xe NMR shielding allows efficient studies of the phase behaviour and structure of complex systems containing thousands of molecules, and brings us closer to the simulation of NMR experiments.
Integrated fiber-mirror ion trap for strong ion-cavity coupling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brandstätter, B., E-mail: birgit.brandstaetter@uibk.ac.at; Schüppert, K.; Casabone, B.
2013-12-15
We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvaturemore » and ellipticities of the fiber mirrors. From finesse measurements, we infer a single-atom cooperativity of up to 12 for FFPCs longer than 200 μm in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We characterize the birefringence of our fiber mirrors, finding that careful fiber-mirror selection enables us to construct FFPCs with degenerate polarization modes. As FFPCs are novel devices, we describe procedures developed for handling, aligning, and cleaning them. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. X-ray photoelectron spectroscopy measurements indicate that these losses may be attributable to oxygen depletion in the mirror coating. Special design considerations enable us to introduce a FFPC into a trapped ion setup. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate distortions of the potential due to the fibers. Home-built fiber feedthroughs connect the FFPC to external optics, and an integrated nanopositioning system affords the possibility of retracting or realigning the cavity without breaking vacuum.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cano, A.; Osiry, H.; Reguera, L.
The titled compound was prepared by the precipitation method from diluted aqueous solution of sodium nitroprusside and mercury(II) nitrate. The orange solid formed, with formula unit Hg[Fe(CN){sub 5}NO], crystallizes with an orthorhombic unit cell in the Pmna space group with cell parameters: a=11.2788(3), b=6.1965(3), and c=12.3786(6) Å. The unit cell accommodates four formula of the compound (Z=4). Its crystal structure was solved from X-ray powder patterns and then refined by the Rietveld method. The material framework is formed by tetrahedral coordination of Hg atoms at the N end of the equatorial CN groups of the [Fe(CN){sub 5}NO] building block. Thatmore » framework results from the interpenetration of two identical sub-frameworks with a relative shift of (a/2, b/2, c/2). The sub-framework has two types of cavities, ellipsoidal and rhombohedral, with transversal section of ca. 4.5×9.2 Å and ca. 8.5 Å transversal section, respectively. That system of cavities results eclipsed by the relative shift of neighboring sub-frameworks. No transport of H{sub 2} and N{sub 2} molecules through the material framework was observed. The thermal decomposition also reveals limitation for the decomposition products diffusion through the practically compact structure. The structural study was complemented with TG, IR, UV–vis and N{sub 2} and H{sub 2} adsorption data. Neighboring Hg atoms are distant 4.54(3) Å, a relatively large distance to suppose the existence of metal–metal interaction. No previous study on the crystal structure and related properties of mercury(II) nitroprusside has been reported. - Graphical abstract: Mercury(II) nitroprusside framework formed by two identical interpenetrated porous subframeworks where neighboring cavities appear eclipsed. - Highlights: • Interpenetrated frameworks in metal nitroprusside. • Eclipsed porous framework in metal nitroprusside. • Structure and related properties for mercury(II) nitroprusside. • Spectral features for mercury(II) nitroprusside.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Choi, Clara Y.H.; Chang, Steven D.; Gibbs, Iris C.
2012-11-01
Purpose: Single-modality treatment of large brain metastases (>2 cm) with whole-brain irradiation, stereotactic radiosurgery (SRS) alone, or surgery alone is not effective, with local failure (LF) rates of 50% to 90%. Our goal was to improve local control (LC) by using multimodality therapy of surgery and adjuvant SRS targeting the resection cavity. Patients and Methods: We retrospectively evaluated 97 patients with brain metastases >2 cm in diameter treated with surgery and cavity SRS. Local and distant brain failure (DF) rates were analyzed with competing risk analysis, with death as a competing risk. The overall survival rate was calculated by themore » Kaplain-Meier product-limit method. Results: The median imaging follow-up duration for all patients was 10 months (range, 1-80 months). The 12-month cumulative incidence rates of LF, with death as a competing risk, were 9.3% (95% confidence interval [CI], 4.5%-16.1%), and the median time to LF was 6 months (range, 3-17 months). The 12-month cumulative incidence rate of DF, with death as a competing risk, was 53% (95% CI, 43%-63%). The median survival time for all patients was 15.6 months. The median survival times for recursive partitioning analysis classes 1, 2, and 3 were 33.8, 13.7, and 9.0 months, respectively (p = 0.022). On multivariate analysis, Karnofsky Performance Status ({>=}80 vs. <80; hazard ratio 0.54; 95% CI 0.31-0.94; p = 0.029) and maximum preoperative tumor diameter (hazard ratio 1.41; 95% CI 1.08-1.85; p = 0.013) were associated with survival. Five patients (5%) required intervention for Common Terminology Criteria for Adverse Events v4.02 grade 2 and 3 toxicity. Conclusion: Surgery and adjuvant resection cavity SRS yields excellent LC of large brain metastases. Compared with other multimodality treatment options, this approach allows patients to avoid or delay whole-brain irradiation without compromising LC.« less
Morishige, Kunimitsu; Tateishi, Masayoshi; Hirose, Fumi; Aramaki, Kenji
2006-10-24
To verify pore blocking controlled desorption in ink-bottle pores, we measured the temperature dependence of the adsorption-desorption isotherms of nitrogen on four kinds of KIT-5 samples with expanded cavities hydrothermally treated for different periods of time at 393 K. In the samples, almost spherical cavities are arranged in a face-centered cubic array and the cavities are connected through small channels. The pore size of the channels increased with an increase in the hydrothermal treatment time. At lower temperatures a steep desorption branch changed to a gradual one as the hydrothermal treatment was prolonged. For the sample hydrothermally treated only for 1 day, the rectangular hysteresis loop shrank gradually with increasing temperature while keeping its shape. The temperature dependence of the evaporation pressure observed was identical with that expected for cavitation-controlled desorption. On the other hand, for the samples hydrothermally treated for long times, the gradual desorption branch became a sharp one with increasing temperature. This strongly suggests that the desorption mechanism is altered from pore blocking to cavitation with temperature. Application of percolation theory to the pore blocking controlled desorption observed here is discussed.
Josephson Parametric Amplifer Based on a Cavity-Embedded Cooper Pair Transistor
NASA Astrophysics Data System (ADS)
Li, Juliang; Rimberg, A. J.
In this experiment a cavity-embedded Cooper-pair transistor (cCPT) is used as a Josephson parametric amplifier. The cCPT consists of a Cooper pair transistor placed at the voltage antinode of a 5.7 GHz shorted quarter-wave resonator so that the CPT provides a galvanic connection between the cavity's central conductor and ground plane, which forms a SQUID loop. Both the flux threading the loop as well as the gate charge can be modulated, and each can provide the parametric pumping. The reflected signal from the cCPT is further amplified by both SLUG and HEMT amplifiers for characterizing the parametric amplification. A first application of the parametric amplification is to improve the charge sensitivity of a single electron charge detector. This can be done either by pumping on a side band or by shifting the charge state of the cCPT near a bifurcation point. Stimulated emission has been also observed when the cCPT is pumped at twice the resonant frequency in the absence of an input signal. This could allow investigation of the dynamic Casimir effect as well as generation of non-classical photon states. Supported by Grants ARO W911NF-13-10377 and NSF DMR 1507400.
[Juvenile idiopathic arthritis and oral health].
Kobus, Agnieszka; Kierklo, Anna; Sielicka, Danuta; Szajda, Sławomir Dariusz
2016-05-04
Juvenile idiopathic arthritis (JIA) is the most common autoimmune inflammatory disease of connective tissue in children. It is characterized by progressive joint destruction which causes preserved changes in the musculoskeletal system. The literature describes fully clinical symptoms and radiological images in different subtypes of JIA. However, there is still a limited number of studies reporting on the medical condition of the oral cavity of ill children. JIA can affect hard and soft tissues of the oral cavity by: the general condition of the child's health, arthritis of the upper limbs, as the result of the pharmacotherapy, changes in secretion and composition of saliva, inflammation of the temporomandibular joint and facial deformity. The study summarizes the available literature on the condition of the teeth and periodontal and oral hygiene in the course of JIA. The presence of diverse factors that modify the oral cavity, such as facial growth, functioning of salivary glands, or the supervision and care provided by adults, prevents clear identification if JIA leads to severe dental caries and periodontal disease. Despite conflicting results in studies concerning the clinical oral status, individuals with JIA require special attention regarding disease prevention and maintenance of oral health.
Improved drainage with active chest tube clearance.
Shiose, Akira; Takaseya, Tohru; Fumoto, Hideyuki; Arakawa, Yoko; Horai, Tetsuya; Boyle, Edward M; Gillinov, A Marc; Fukamachi, Kiyotaka
2010-05-01
This study was performed to evaluate the efficacy of a novel chest drainage system. This system employs guide wire-based active chest tube clearance to improve drainage and maintain patency. A 32 Fr chest tube was inserted into pleural cavities of five pigs. On the left, a tube was connected to the chest canister, and on the right, the new system was inserted between the chest tube and chest canister. Acute bleeding was mimicked by periodic infusion of blood. The amount of blood drained from each chest cavity was recorded every 15 min for 2 h. After completion of the procedure, all residual blood and clots in each chest cavity were assessed. The new system remained widely patent, and the amount of drainage achieved with this system (670+/-105 ml) was significantly (P=0.01) higher than that with the standard tube (239+/-131 ml). The amount of retained pleural blood and clots with this system (150+/-107 ml) was significantly (P=0.04) lower than that with the standard tube (571+/-248 ml). In conclusion, a novel chest drainage system with active tube clearance significantly improved drainage without tube manipulations. 2010 Published by European Association for Cardio-Thoracic Surgery. All rights reserved.
Tympanic-response transition in ICE: Dependence upon the interaural cavity's shape
NASA Astrophysics Data System (ADS)
van Hemmen, J. Leo
More than half of the terrestrial vertebrates have internally coupled ears (ICE), where an interaural cavity of some shape acoustically couples the eardrums. Hence what the animal's auditory system perceives is not the outside stimulus but the superposition of outside and internal pressure on the two eardrums, resulting in so-called internal time and level difference, iTD and iLD, which are keys to sound localization. For a cylindrical shape, it is known that on the frequency axis two domains with appreciably increased iTD and iLD values occur, segregated by the eardrum's fundamental frequency. Here we analyze the case where, as in nature, two or more canals couple the eardrums so that, by opening one of the canals, the animal can switch from coupled to two independent ears. We analyze the iTD/iLD transition and its dependence upon the interaural cavity's size and shape. As compared to a single connection, the iTD performance is preserved to a large extent. Nonetheless, the price to pay for freedom of choice is a reduced frequency range with high-iTD plateau. Work done in collaboration with A.P. Vedurmudi; partially supported by BCCN-Munich.
Electromagnetic Field Penetration Studies
NASA Technical Reports Server (NTRS)
Deshpande, M.D.
2000-01-01
A numerical method is presented to determine electromagnetic shielding effectiveness of rectangular enclosure with apertures on its wall used for input and output connections, control panels, visual-access windows, ventilation panels, etc. Expressing EM fields in terms of cavity Green's function inside the enclosure and the free space Green's function outside the enclosure, integral equations with aperture tangential electric fields as unknown variables are obtained by enforcing the continuity of tangential electric and magnetic fields across the apertures. Using the Method of Moments, the integral equations are solved for unknown aperture fields. From these aperture fields, the EM field inside a rectangular enclosure due to external electromagnetic sources are determined. Numerical results on electric field shielding of a rectangular cavity with a thin rectangular slot obtained using the present method are compared with the results obtained using simple transmission line technique for code validation. The present technique is applied to determine field penetration inside a Boeing-757 by approximating its passenger cabin as a rectangular cavity filled with a homogeneous medium and its passenger windows by rectangular apertures. Preliminary results for, two windows, one on each side of fuselage were considered. Numerical results for Boeing-757 at frequencies 26 MHz, 171-175 MHz, and 428-432 MHz are presented.
Gas in scattering media absorption spectroscopy - GASMAS
NASA Astrophysics Data System (ADS)
Svanberg, Sune
2008-09-01
An overview of the new field of Gas in Scattering Media Absorption Spectroscopy (GASMAS) is presented. GASMAS combines narrow-band diode-laser spectroscopy with diffuse media optical propagation. While solids and liquids have broad absorption features, free gas in pores and cavities in the material is characterized by sharp spectral signatures, typically 10,000 times sharper than those of the host material. Many applications in materials science, food packaging, pharmaceutics and medicine have been demonstrated. So far molecular oxygen and water vapour have been studied around 760 and 935 nm, respectively. Liquid water, an important constituent in many natural materials, such as tissue, has a low absorption at such wavelengths, allowing propagation. Polystyrene foam, wood, fruits, food-stuffs, pharmaceutical tablets, and human sinus cavities have been studied. Transport of gas in porous media can readily be studied by first immersing the material in, e.g., pure nitrogen, and then observing the rate at which normal air, containing oxygen, reinvades the material. The conductance of the sinus connective passages can be measured in this way by flushing the nasal cavity with nitrogen. Also other dynamic processes such as drying of materials can be studied. The techniques have also been extended to remote-sensing applications (LIDAR-GASMAS).
Operating safety of a hot-shot wind tunnel with combined test gas heating in stabilization mode
NASA Astrophysics Data System (ADS)
Shumskii, V. V.; Yaroslavtsev, M. I.
2017-07-01
In the present paper, we analyze emergency situations typical of short-duration wind tunnels with electric-arc or combined test-gas heating in the presence of stabilization and diaphragm-rupturing systems, which occur in the case of no discharge initiation in the settling chamber, with the capacitor battery having remained charged during the start of wind-tunnel systems. For avoiding such emergency situations, some additional changes based on using feedback elements are introduced into the wind-tunnel design: the piston of the fast-response valve is made hollow for increasing the volume of the shutoff cavity and for making the release of pressure from this cavity unnecessary; the high-pressure channel, which connects the piston and the piston rod with the settling-chamber cavity, is filled with a liquid and is closed from the side of the settling chamber with a piston; the device for controlled diaphragm breakdown is provided with an external electric circuit intended to control the diaphragm-rupturing process. Those modifications allow subsequent functioning of the wind-tunnel systems only in the presence of heat-supply-induced pressure growth in the settling chamber of the wind tunnel.
Tripartite counterfactual entanglement distribution.
Chen, Yuanyuan; Gu, Xuemei; Jiang, Dong; Xie, Ling; Chen, Lijun
2015-08-10
We propose two counterfactual schemes for tripartite entanglement distribution without any physical particles travelling through the quantum channel. One scheme arranges three participators to connect with the absorption object by using switch. Using the "chained" quantum Zeno effect, three participators can accomplish the task of entanglement distribution with unique counterfactual interference probability. Another scheme uses Michelson-type interferometer to swap two entanglement pairs such that the photons of three participators are entangled. Moreover, the distance of entanglement distribution is doubled as two distant absorption objects are used. We also discuss the implementation issues to show that the proposed schemes can be realized with current technology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daly, Megan E.; Chen, Allen M.; Bucci, M. Kara
Purpose: To report the clinical outcome of patients treated with intensity-modulated radiation therapy (IMRT) for malignancies of the nasal cavity and paranasal sinuses. Methods and Materials: Between 1998 and 2004, 36 patients with malignancies of the sinonasal region were treated with IMRT. Thirty-two patients (89%) were treated in the postoperative setting after gross total resection. Treatment plans were designed to provide a dose of 70 Gy to 95% or more of the gross tumor volume (GTV) and 60 Gy to 95% or more of the clinical tumor volume (CTV) while sparing neighboring critical structures including the optic chiasm, optic nerves,more » eyes, and brainstem. The primary sites were: 13 ethmoid sinus, 10 maxillary sinus, 7 nasal cavity, and 6 other. Histology was: 12 squamous cell, 7 esthesioneuroblastoma, 5 adenoid cystic, 5 undifferentiated, 5 adenocarcinoma, and 2 other. Median follow-up was 51 months among surviving patients (range, 9-82 months). Results: The 2-year and 5-year estimates of local control were 62% and 58%, respectively. One patient developed isolated distant metastasis, and none developed isolated regional failure. The 5-year rates of disease-free and overall survival were 55% and 45%, respectively. The incidence of ocular toxicity was minimal with no patients reporting decreased vision. Late complications included xerophthalmia (1 patient), lacrimal stenosis (1 patient), and cataract (1 patient). Conclusion: Although IMRT for malignancies of the sinonasal region does not appear to lead to significant improvements in disease control, the low incidence of complications is encouraging.« less
Ovarian Cancer Stroma: Pathophysiology and the Roles in Cancer Development
Furuya, Mitsuko
2012-01-01
Ovarian cancer represents one of the cancers with the worst prognostic in adult women. More than half of the patients who present with clinical signs such as abdominal bloating and a feeling of fullness already show advanced stages. The majority of ovarian cancers grow as cystic masses, and cancer cells easily spread into the pelvic cavity once the cysts rupture or leak. When the ovarian cancer cells disseminate into the peritoneal cavity, metastatic nests may grow in the cul-de-sac, and in more advanced stages, the peritoneal surfaces of the upper abdomen become the next largest soil for cancer progression. Ascites is also produced frequently in ovarian cancers, which facilitates distant metastasis. Clinicopathologic, epidemiologic and molecular studies on ovarian cancers have improved our understanding and therapeutic approaches, but still further efforts are required to reduce the risks in the patients who are predisposed to this lethal disease and the mortality of the patients in advanced stages. Among various molecules involved in ovarian carcinogenesis, special genes such as TP53, BRCA1 and BRCA2 have been well investigated. These genes are widely accepted as the predisposing factors that trigger malignant transformation of the epithelial cells of the ovary. In addition, adnexal inflammatory conditions such as chronic salpingitis and ovarian endometriosis have been great research interests in the context of carcinogenic background of ovarian cancers. In this review, I discuss the roles of stromal cells and inflammatory factors in the carcinogenesis and progression of ovarian cancers. PMID:24213462
Configuration and Calibration of High Temperature Furnaces for Testing Ceramic Matrix Composites
2014-10-01
Actual Furnace Cavity Stainless Steel Mesh Cage For Electrical Connections (both sides) High Temperature Power Lead Clamp Furnace Control TC’s Power... tests generate the basic properties such as modulus (E), ultimate tensile strength (UTS), proportional limit (PL), strain at failure (f), as well as...stress- strain behavior. Each material was tested at room temperature, at the maximum use temperature for the CMC system (as determined by the CMC
Four photon parametric amplification. [in unbiased Josephson junction
NASA Technical Reports Server (NTRS)
Parrish, P. T.; Feldman, M. J.; Ohta, H.; Chiao, R. Y.
1974-01-01
An analysis is presented describing four-photon parametric amplification in an unbiased Josephson junction. Central to the theory is the model of the Josephson effect as a nonlinear inductance. Linear, small signal analysis is applied to the two-fluid model of the Josephson junction. The gain, gain-bandwidth product, high frequency limit, and effective noise temperature are calculated for a cavity reflection amplifier. The analysis is extended to multiple (series-connected) junctions and subharmonic pumping.
Hübler, Merla J; Buchman, Timothy G
2008-02-01
To model the effects of system connectedness on recovery of dysfunctional tissues. One-dimensional elementary cellular automata models with small-world features, where the center-input for a few cells comes not from itself but, with a given probability, from another cell. This probability represents the connectivity of the network. The long-range connections are chosen randomly to survey the potential influences of distant information flowing into a local region. MATLAB and Mathematica computing environments. None. None. We determined the recovery rate of the entropy after perturbing a uniformly dormant system. We observed that the recovery of normal activity after perturbation of a dormant system had the characteristics of an epidemic. Moreover, we found that the rate of recovery to normal steady-state activity increased rapidly even for small amounts of long-range connectivity. Findings obtained through numerical simulation were verified through analytical solutions. This study links our hypothesis that multiple organ function syndromes represent recoupling failure with a mathematical model showing the contribution of such coupling to reactivation of dormant systems. The implication is that strategies aimed not at target tissues or target organs but rather at restoring the quality and quantity of interconnections across those tissues and organs may be a novel therapeutic strategy.
The use of CVD diamond burs for ultraconservative cavity preparations: a report of two cases.
Carvalho, Carlos Augusto R; Fagundes, Ticiane C; Barata, Terezinha J E; Trava-Airoldi, Vladimir Jesus; Navarro, Maria Fidela L
2007-01-01
During the past decades, scientific developments in cutting instruments have changed the conventional techniques used to remove caries lesions. Ultrasound emerged as an alternative for caries removal since the 1950s. However, the conventional technology for diamond powder aggregation with nickel metallic binders could not withstand ultrasonic power. Around 5 years ago, an alternative approach using chemical vapor deposition (CVD) resulted in synthetic diamond technology. CVD diamond burs are obtained with high adherence of the diamond as a unique stone on the metallic surface with excellent abrading performance. This technology allows for diamond deposition with coalescent granulation in different formats of substrates. When connected to an ultrasonic handpiece, CVD diamond burs become an option for cavity preparation, maximizing preservation of tooth structure. Potential advantages such as reduced noise, minimal damage to the gingival tissue, extended bur durability, improved proximal cavity access, reduced risk of hitting the adjacent tooth resulting from the high inclination angles, and minimal patient's risk of metal contamination. These innovative instruments also potentially eliminate some problems regarding decreased cutting efficiency of conventional diamond burs. This clinical report presents the benefits of using CVD diamond burs coupled with an ultrasonic handpiece in the treatment of incipient caries. CVD diamond burs coupled with an ultrasonic device offer a promising alternative for removal of carious lesions when ultraconservative cavity preparations are required. Additionally, this system provides a less-painful technique for caries removal, with minimal noise.
Regularized quasinormal modes for plasmonic resonators and open cavities
NASA Astrophysics Data System (ADS)
Kamandar Dezfouli, Mohsen; Hughes, Stephen
2018-03-01
Optical mode theory and analysis of open cavities and plasmonic particles is an essential component of optical resonator physics, offering considerable insight and efficiency for connecting to classical and quantum optical properties such as the Purcell effect. However, obtaining the dissipative modes in normalized form for arbitrarily shaped open-cavity systems is notoriously difficult, often involving complex spatial integrations, even after performing the necessary full space solutions to Maxwell's equations. The formal solutions are termed quasinormal modes, which are known to diverge in space, and additional techniques are frequently required to obtain more accurate field representations in the far field. In this work, we introduce a finite-difference time-domain technique that can be used to obtain normalized quasinormal modes using a simple dipole-excitation source, and an inverse Green function technique, in real frequency space, without having to perform any spatial integrations. Moreover, we show how these modes are naturally regularized to ensure the correct field decay behavior in the far field, and thus can be used at any position within and outside the resonator. We term these modes "regularized quasinormal modes" and show the reliability and generality of the theory by studying the generalized Purcell factor of dipole emitters near metallic nanoresonators, hybrid devices with metal nanoparticles coupled to dielectric waveguides, as well as coupled cavity-waveguides in photonic crystals slabs. We also directly compare our results with full-dipole simulations of Maxwell's equations without any approximations, and show excellent agreement.
Huber, Gerhard F; Züllig, Lena; Soltermann, Alex; Roessle, Matthias; Graf, Nicole; Haerle, Stephan K; Studer, Gabriela; Jochum, Wolfram; Moch, Holger; Stoeckli, Sandro J
2011-06-03
Prognostic factors in predicting occult lymph node metastasis in patients with head and neck squamous-cell carcinoma (HNSCC) are necessary to improve the results of the sentinel lymph node procedure in this tumour type. The E-Cadherin glycoprotein is an intercellular adhesion molecule in epithelial cells, which plays an important role in establishing and maintaining intercellular connections. To determine the value of the molecular marker E-Cadherin in predicting regional metastatic disease. E-Cadherin expression in tumour tissue of 120 patients with HNSCC of the oral cavity and oropharynx were evaluated using the tissue microarray technique. 110 tumours were located in the oral cavity (91.7%; mostly tongue), 10 tumours in the oropharynx (8.3%). Intensity of E-Cadherin expression was quantified by the Intensity Reactivity Score (IRS). These results were correlated with the lymph node status of biopsied sentinel lymph nodes. Univariate and multivariate analysis was used to determine statistical significance. pT-stage, gender, tumour side and location did not correlate with lymph node metastasis. Differentiation grade (p = 0.018) and down regulation of E-Cadherin expression significantly correlate with positive lymph node status (p = 0.005) in univariate and multivariate analysis. These data suggest that loss of E-cadherin expression is associated with increased lymhogeneous metastasis of HNSCC. E-cadherin immunohistochemistry may be used as a predictor for lymph node metastasis in squamous cell carcinoma of the oral cavity and oropharynx. 2b.
Investigation of a broadband duct noise control system inspired by the middle ear mechanism
NASA Astrophysics Data System (ADS)
Wang, Chunqi; Huang, Lixi
2012-08-01
A new duct noise control device is introduced based on the mechanism of human middle ear which functions as a compact, broadband impedance transformer between the air motion in the outer ear and the liquid motion in the inner ear. The system consists of two rigid endplates, simulating the tympanic membrane and the stapes footplate, and they are connected by a single rigid rod, simulating the overall action of the ossicular chain. These three pieces are placed in a side-branch cavity, and the whole device is called an ossicular silencer. A specific configuration is investigated numerically with a two-dimensional finite element model. Results show that broadband noise attenuation can be achieved in the very low frequency regime. Typically, two or more resonance peaks are found and the transmission loss between two neighbouring peaks is maintained at a high level. The cavity length is found to be the most crucial parameter that determines the effective frequency range of the ossicular silencer. The total cavity volume, which is a major controlling factor in most existing noise control devices, becomes less influential. The fluid medium in the enclosed cavity mainly acts like an added mass, while its stiffness effect is negligible. Simplified plane wave analysis is also conducted to reveal the mechanisms of the system resonances. The first resonance is identified as of the mass-spring system with mass contributions from both fluid and the plates, while the second one is of the Herschel-Quincke (HQ) tube resonance.
Spin-controlled ultrafast vertical-cavity surface-emitting lasers
NASA Astrophysics Data System (ADS)
Höpfner, Henning; Lindemann, Markus; Gerhardt, Nils C.; Hofmann, Martin R.
2014-05-01
Spin-controlled semiconductor lasers are highly attractive spintronic devices providing characteristics superior to their conventional purely charge-based counterparts. In particular, spin-controlled vertical-cavity surface emitting lasers (spin-VCSELs) promise to offer lower thresholds, enhanced emission intensity, spin amplification, full polarization control, chirp control and ultrafast dynamics. Most important, the ability to control and modulate the polarization state of the laser emission with extraordinarily high frequencies is very attractive for many applications like broadband optical communication and ultrafast optical switches. We present a novel concept for ultrafast spin-VCSELs which has the potential to overcome the conventional speed limitation for directly modulated lasers by the relaxation oscillation frequency and to reach modulation frequencies significantly above 100 GHz. The concept is based on the coupled spin-photon dynamics in birefringent micro-cavity lasers. By injecting spin-polarized carriers in the VCSEL, oscillations of the coupled spin-photon system can by induced which lead to oscillations of the polarization state of the laser emission. These oscillations are decoupled from conventional relaxation oscillations of the carrier-photon system and can be much faster than these. Utilizing these polarization oscillations is thus a very promising approach to develop ultrafast spin-VCSELs for high speed optical data communication in the near future. Different aspects of the spin and polarization dynamics, its connection to birefringence and bistability in the cavity, controlled switching of the oscillations, and the limitations of this novel approach will be analysed theoretically and experimentally for spin-polarized VCSELs at room temperature.
Accessory hepatic vein complicating extra-cardiac total cavopulmonary connection.
Yoshii, Shinpei; Suzuki, Shoji; Osawa, Hiroshi; Hosaka, Shigeru; Honda, Yoshihiro; Abraham, Samuel J K; Tada, Yusuke; Sugiyama, Hisashi; Tan, Tetsushi; Kadono, Toshie; Hoshiai, Minako; Komai, Takayuki
2002-04-01
We encountered unexpected, severe hypoxia after the right heart bypass operation in a patient with isomerism. A 2-year-old girl with polysplenia had a complex cardiac anomaly consisting of a single atrium, single ventricle, pulmonary stenosis, absence of the right superior vena cava, hemiazygos continuation of the left inferior vena cava, and d-malposition of the great arteries. After a total cavopulmonary shunt, we performed an extra-cardiac total cavo-pulmonary connection with a 14 mm tube graft. The postoperative course was complicated by severe hypoxia. Angiography performed 20 days after the operation showed that contrast medium in the conduit poured into the hepatic vein, and through the intrahepatic communications, it passed into a left-sided accessory hepatic vein, which was connected directly to the left side of the aspect of the atrium. As the intrahepatic communication was adequate, we ligated the accessory hepatic vein within the pericardial cavity. The SpO2 returned to normal and no hepatic dysfunction was detected. We conclude that surgeons performing extra-cardiac total cavopulmonary connection need to pay closer attention to the possibility that an accessory hepatic vein might exist.
Crystal structures of dye-decolorizing peroxidase with ascorbic acid and 2,6-dimethoxyphenol.
Yoshida, Toru; Tsuge, Hideaki; Hisabori, Toru; Sugano, Yasushi
2012-12-14
The structure of dye-decolorizing peroxidase (DyP)-type peroxidase differs from that of other peroxidase families, indicating that DyP-type peroxidases have a different reaction mechanism. We have determined the crystal structures of DyP with ascorbic acid and 2,6-dimethoxyphenol at 1.5 and 1.4Å, respectively. The common binding site for both substrates was located at the entrance of the second cavity leading from the DyP molecular surface to heme. This resulted in a hydrogen bond network connection between each substrate and the heme distal side. This network consisted of water molecules occupying the second cavity, heme 6-propionate, Arg329, and Asn313. This network is consistent with the proton transfer pathway from substrate to DyP. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Endometrial stromal sarcoma mimicking submucosal myoma protruding to the vagina: MRI findings.
Chien, J C W; Hsieh, S C; Lee, R C; Chen, C Y; Cheng, C J; Chan, W P
2005-01-01
A 46-year-old woman complained of persistent abnormal vaginal bleeding over ten days. Her intrauterine device had been removed two years before. Soon after, she suffered from menorrhagia and metrorrhagia. An incidental finding of severe anemia was also noted. In this admission, our initial T2-weighted magnetic resonance imaging (MRI) revealed a well-demarcated mass predominantly in the uterine cavity. The mass was depicted by an isointense signal relative to the myometrium on T1-weighted images, high signal intensity on T2-weighted images, and slightly heterogeneous enhancement on post-contrast images. The patient refused surgery. After two years, follow-up MRI showed a pedunculated mass protruding into the upper third of the vagina with a stalk connecting to the posterior wall of the uterine cavity, simulating submucosal myoma. Histological diagnosis was compatible with low-grade endometrial stromal sarcoma.
Kemp, Mark A
2015-11-03
A high power RF device has an electron beam cavity, a modulator, and a circuit for feed-forward energy recovery from a multi-stage depressed collector to the modulator. The electron beam cavity include a cathode, an anode, and the multi-stage depressed collector, and the modulator is configured to provide pulses to the cathode. Voltages of the electrode stages of the multi-stage depressed collector are allowed to float as determined by fixed impedances seen by the electrode stages. The energy recovery circuit includes a storage capacitor that dynamically biases potentials of the electrode stages of the multi-stage depressed collector and provides recovered energy from the electrode stages of the multi-stage depressed collector to the modulator. The circuit may also include a step-down transformer, where the electrode stages of the multi-stage depressed collector are electrically connected to separate taps on the step-down transformer.
Cryogenic mount for mirror and piezoelectric actuator for an optical cavity.
Oliveira, A N; Moreira, L S; Sacramento, R L; Kosulic, L; Brasil, V B; Wolff, W; Cesar, C L
2017-06-01
We present the development of a mount that accommodates a mirror and a piezoelectric actuator with emphasis on physical needs for low temperature operation. The design uses a monolithic construction with flexure features that allow it to steadily hold the mirror and the piezoelectric actuator without glue and accommodate differential thermal contraction. The mount is small and lightweight, adding little heat capacity and inertia. It provides a pre-loading of the piezoelectric actuator as well as a good thermal connection to the mirror and a thermal short across the piezoelectric actuator. The performance of the assemblies has been tested by thermally cycling from room temperature down to 3 K more than a dozen times and over one hundred times to 77 K, without showing any derating. Such mounts are proposed for the cryogenic optical enhancement cavities of the ALPHA experiment at CERN for laser spectroscopy of antihydrogen and for hydrogen spectroscopy in our laboratory at UFRJ.
Cavity Forming Pneumonia Due to Staphylococcus aureus Following Dengue Fever.
Miyata, Nobuyuki; Yoshimura, Yukihiro; Tachikawa, Natsuo; Amano, Yuichiro; Sakamoto, Yohei; Kosuge, Youko
2015-11-01
While visiting Malaysia, a 22-year-old previously healthy Japanese man developed myalgia, headache, and fever, leading to a diagnosis of classical dengue fever. After improvement and returning to Japan after a five day hospitalization, he developed productive cough several days after defervescing from dengue. Computed tomography (CT) thorax scan showed multiple lung cavities. A sputum smear revealed leukocytes with phagocytized gram-positive cocci in clusters, and grew an isolate Staphylococcus aureus sensitive to semi-synthetic penicillin; he was treated successfully with ceftriaxone and cephalexin. This second reported case of pneumonia due to S. aureus occurring after dengue fever, was associated both with nosocomial exposure and might have been associated with dengue-associated immunosuppression. Clinicians should pay systematic attention to bacterial pneumonia following dengue fever to establish whether such a connection is causally associated. © The American Society of Tropical Medicine and Hygiene.
Mode coupling in hybrid square-rectangular lasers for single mode operation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ma, Xiu-Wen; Huang, Yong-Zhen, E-mail: yzhuang@semi.ac.cn; Yang, Yue-De
Mode coupling between a square microcavity and a Fabry-Pérot (FP) cavity is proposed and demonstrated for realizing single mode lasers. The modulations of the mode Q factor as simulation results are observed and single mode operation is obtained with a side mode suppression ratio of 46 dB and a single mode fiber coupling loss of 3.2 dB for an AlGaInAs/InP hybrid laser as a 300-μm-length and 1.5-μm-wide FP cavity connected to a vertex of a 10-μm-side square microcavity. Furthermore, tunable single mode operation is demonstrated with a continuous wavelength tuning range over 10 nm. The simple hybrid structure may shed light on practicalmore » applications of whispering-gallery mode microcavities in large-scale photonic integrated circuits and optical communication and interconnection.« less
Cavity resonance absorption in ultra-high bandwidth CRT deflection structure by a resistive load
Dunham, M.E.; Hudson, C.L.
1993-05-11
An improved ultra-high bandwidth helical coil deflection structure for a cathode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to the first and second ground planes, the resistive load having an impedance substantially equal to the characteristic impedance of the coaxial line formed by the two coaxial ground planes to inhibit cavity resonance in the structure within the ultra-high bandwidth of operation. Preferably, the resistive load comprises a carbon film on a surface of an end plug in one end of the bore.
Cavity resonance absorption in ultra-high bandwidth CRT deflection structure by a resistive load
Dunham, Mark E.; Hudson, Charles L.
1993-01-01
An improved ultra-high bandwidth helical coil deflection structure for a hode ray tube is described comprising a first metal member having a bore therein, the metal walls of which form a first ground plane; a second metal member coaxially mounted in the bore of the first metal member and forming a second ground plane; a helical deflection coil coaxially mounted within the bore between the two ground planes; and a resistive load disposed in one end of the bore and electrically connected to the first and second ground planes, the resistive load having an impedance substantially equal to the characteristic impedance of the coaxial line formed by the two coaxial ground planes to inhibit cavity resonance in the structure within the ultra-high bandwidth of operation. Preferably, the resistive load comprises a carbon film on a surface of an end plug in one end of the bore.
Lau, K Y; Abu Bakar, M H; Muhammad, F D; Latif, A A; Omar, M F; Yusoff, Z; Mahdi, M A
2018-05-14
Mode-locked fiber laser incorporating a saturable absorber is an attractive configuration due to its stability and simple structure. In this work, we demonstrate a dual-wavelength passively mode-locked erbium-doped fiber laser employing a graphene/polymethyl-methacrylate saturable absorber. A laser resonator is developed based on dual cavity architecture with unidirectional signal oscillation, which is connected by a fiber branch sharing a common gain medium and saturable absorber. Dual wavelength mode-locked fiber lasers are observed at approximately 1530 and 1560 nm with 22.6 mW pump power threshold. Soliton pulse circulates in the laser cavity with pulse duration of 900 and 940 fs at shorter and longer wavelengths, respectively. This work presents a viable option in developing a low threshold mode-locked laser source with closely spaced dual wavelength femtosecond pulses in the C-band wavelength region.
Bridging ultrahigh-Q devices and photonic circuits
NASA Astrophysics Data System (ADS)
Yang, Ki Youl; Oh, Dong Yoon; Lee, Seung Hoon; Yang, Qi-Fan; Yi, Xu; Shen, Boqiang; Wang, Heming; Vahala, Kerry
2018-05-01
Optical microresonators are essential to a broad range of technologies and scientific disciplines. However, many of their applications rely on discrete devices to attain challenging combinations of ultra-low-loss performance (ultrahigh Q) and resonator design requirements. This prevents access to scalable fabrication methods for photonic integration and lithographic feature control. Indeed, finding a microfabrication bridge that connects ultrahigh-Q device functions with photonic circuits is a priority of the microcavity field. Here, an integrated resonator having a record Q factor over 200 million is presented. Its ultra-low-loss and flexible cavity design brings performance to integrated systems that has been the exclusive domain of discrete silica and crystalline microcavity devices. Two distinctly different devices are demonstrated: soliton sources with electronic repetition rates and high-coherence/low-threshold Brillouin lasers. This multi-device capability and performance from a single integrated cavity platform represents a critical advance for future photonic circuits and systems.
2010-01-01
The incidence of oral squamous cell carcinoma remains high. Oral and oro-pharyngeal carcinomas are the sixth most common cancer in the world. Several clinicopathological parameters have been implicated in prognosis, recurrence and survival, following oral squamous cell carcinoma. In this retrospective analysis, clinicopathological parameters of 115 T1/T2 OSCC were studied and compared to recurrence and death from tumour-related causes. The study protocol was approved by the Joint UCL/UCLH committees of the ethics for human research. The patients' data was entered onto proformas, which were validated and checked by interval sampling. The fields included a range of clinical, operative and histopathological variables related to the status of the surgical margins. Data collection also included recurrence, cause of death, date of death and last clinic review. Causes of death were collated in 4 categories (1) death from locoregional spread, (2) death from distant metastasis, (3) death from bronchopulmonary pneumonia, and (4) death from any non-tumour event that lead to cardiorespiratory failure. The patients' population comprised 65 males and 50 females. Their mean age at the 1st diagnosis of OSCC was 61.7 years. Two-thirds of the patients were Caucasians. Primary sites were mainly identified in the tongue, floor of mouth (FOM), buccal mucosa and alveolus. Most of the identified OSCCs were low-risk (T1N0 and T2N0). All patients underwent primary resection ± neck dissection and reconstruction when necessary. Twenty-two patients needed adjuvant radiotherapy. Pathological analysis revealed that half of the patients had moderately differentiated OSCC. pTNM slightly differed from the cTNM and showed that 70.4% of the patients had low-risk OSCC. Tumour clearance was ultimately achieved in 107 patients. Follow-up resulted in a 3-year survival of 74.8% and a 5-year survival of 72.2%. Recurrence was identified in 23 males and 20 females. The mean age of 1st diagnosis of the recurrence group was 59.53 years. Most common oral sites included the lateral border of tongue and floor of mouth. Recurrence was associated with clinical N-stage disease. The surgical margins in this group was evaluated and found that 17 had non-cohesive invasion, 30 had dysplasia at margin, 21 had vascular invasion, 9 had nerve invasion and 3 had bony invasion. Severe dysplasia was present in 37 patients. Tumour clearance was achieved in only 8 patients. The mean depth of tumour invasion in the recurrence group was 7.6 mm. An interesting finding was that 5/11 patients who died of distant metastasis had their primary disease in the tongue. Nodal disease comparison showed that 8/10 patients who died of locoregional metastasis and 8/11 patients who died from distant metastasis had clinical nodal involvement. Comparing this to pathological nodal disease (pTNM) showed that 10/10 patients and 10/11 patients who died from locoregional and distant metastasis, respectively, had nodal disease. All patients who died from locoregional and distant metastasis were shown to have recurrence after the primary tumour resection. Squamous cell carcinoma of the oral cavity has a poor overall prognosis with a high tendency to recur at the primary site and extend to involve the cervical lymph nodes. Several clinicopathological parameters can be employed to assess outcome, recurrence and overall survival. PMID:20406474
Aćimović, Jugoslava; Mäki-Marttunen, Tuomo; Linne, Marja-Leena
2015-01-01
We developed a two-level statistical model that addresses the question of how properties of neurite morphology shape the large-scale network connectivity. We adopted a low-dimensional statistical description of neurites. From the neurite model description we derived the expected number of synapses, node degree, and the effective radius, the maximal distance between two neurons expected to form at least one synapse. We related these quantities to the network connectivity described using standard measures from graph theory, such as motif counts, clustering coefficient, minimal path length, and small-world coefficient. These measures are used in a neuroscience context to study phenomena from synaptic connectivity in the small neuronal networks to large scale functional connectivity in the cortex. For these measures we provide analytical solutions that clearly relate different model properties. Neurites that sparsely cover space lead to a small effective radius. If the effective radius is small compared to the overall neuron size the obtained networks share similarities with the uniform random networks as each neuron connects to a small number of distant neurons. Large neurites with densely packed branches lead to a large effective radius. If this effective radius is large compared to the neuron size, the obtained networks have many local connections. In between these extremes, the networks maximize the variability of connection repertoires. The presented approach connects the properties of neuron morphology with large scale network properties without requiring heavy simulations with many model parameters. The two-steps procedure provides an easier interpretation of the role of each modeled parameter. The model is flexible and each of its components can be further expanded. We identified a range of model parameters that maximizes variability in network connectivity, the property that might affect network capacity to exhibit different dynamical regimes.
Influence of Mach Number and Dynamic Pressure on Cavity Tones and Freedrop Trajectories
2014-03-27
primary purpose is to ensure a steady flow of high pressure air from the compressors to the stagnation chamber. One side of the diaphragm is connected...collected for 20 psi stagnation pressure due to insufficient run times, even at the increased compressor air pressure of 180 psi. Furthermore, the data from...M-36 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR FORCE INSTITUTE OF TECHNOLOGY Wright-Patterson Air Force Base, Ohio DISTRIBUTION STATEMENT A
History of the Biak Operation, 15-27 June 1944
1944-01-01
interconnected by fissures and tunnels. Stalactites and stalagmites add to the near impregnability of the caves as defensive positions. Biak appears to be...level series of intermittently connected cavities about 4 to 8 feet in height and 3 to 6 feet in depth. Stalactite - stalagmite unions and hard...entrance invisible at six paces. In "sump" caves, screening may consist of stalactites and stalagmites which do not conceal the cave mouth, but stop or
Chemical processing in geothermal nuclear chimney
Krikorian, O.H.
1973-10-01
A closed rubble filled nuclear chimney is provided in a subterranean geothermal formation by detonation of a nuclear explosive device therein, with reagent input and product output conduits connecting the chimney cavity with appropriate surface facilities. Such facilities will usually comprise reagent preparation, product recovery and recycle facilities. Proccsses are then conducted in the nuclear chimney which processes are facilitated by temperature, pressure, catalytic and other conditions existent or which are otherwise provided in the nuclear chimney. (auth)
Histological findings after transmyocardial laser revascularization.
Krabatsch, T; Schäper, F; Leder, C; Tülsner, J; Thalmann, U; Hetzer, R
1996-01-01
In recent time, it has become more and more probable that patients with severe diffuse coronary artery disease, who are not candidates for aortocoronary bypass surgery or percutaneous transluminal coronary angioplasty procedures, can benefit from transmyocardial laser revascularization (TMR). But the underlying principle of TMR still remains unclear. This study reports on a histological analysis of eight patients, in whom a total of 250 channels had been created, who died after TMR. The TMR channels were created by a CO2 laser surrounded by a zone of necrosis with an extent of about 500 microns. In the hearts of patients who died in the early postoperative period (1 to 7 days postoperative), almost all channels were closed by fibrin clots, erythrocytes, and macrophages. There were no obvious connections between the channels and the ventricular cavity. In specimens from patients, who died 2 or more weeks after the procedure, a granular tissue with high macrophage and monocyte activity was observable. Within this tissue, we observed a developing network of capillaries. Otherwise, the tissue filling the channels did not substantially differ from scar tissue. We failed to observe connections between the ventricular cavity and the new capillaries. Whether these vessels within the closed channels have any impact on myocardial perfusion remains unclear, but it seems unlikely that the clinical effects of TMR are based on the principle of the amphibian heart.
Increased Ocean Access to Totten Glacier, East Antarctica
NASA Astrophysics Data System (ADS)
Blankenship, D. D.; Greenbaum, J. S.; Young, D. A.; Richter, T. G.; Roberts, J. L.; Aitken, A.; Legresy, B.; Warner, R. C.; van Ommen, T. D.; Siegert, M. J.
2015-12-01
The Totten Glacier is the largest ice sheet outlet in East Antarctica, draining 3.5 meters of eustatic sea level potential from the Aurora Subglacial Basin (ASB) into the Sabrina Coast. Recent work has shown that the ASB has drained and filled many times since largescale glaciation began including evidence that it collapsed during the Pliocene. Steady thinning rates observed near Totten Glacier's grounding line since the beginning of the satellite altimetry record are the largest in East Antarctica and the nature of the thinning suggests that it is driven by enhanced basal melting due to ocean processes. Warm Modified Circumpolar Deep Water (MCDW), which has been linked to glacier retreat in West Antarctica, has been observed in summer and winter on the Sabrina Coast continental shelf in the 400-500 m depth range. Using airborne geophysical data acquired over multiple years we delineate seafloor valleys connecting the inner continental shelf to the cavity beneath Totten Glacier that cut through a large sill centered along the ice shelf calving front. The sill shallows to depths of about 300 mbsl and was likely a grounding line pinning point during Holocene retreat, however, the two largest seafloor valleys are deeper than the observed range of thermocline depths. The deeper of the two valleys, a 4 km-wide trough, connects to the ice shelf cavity through an area of the coastline that was previously believed to be grounded but that our analysis demonstrates is floating, revealing a second, deeper entryway to ice shelf cavity. The previous coastline was charted using satellite-based mapping techniques that infer subglacial properties based on surface expression and behavior; the new geophysical analysis techniques we use enable inferences of subglacial characteristics using direct observations of the ice-water interface. The results indicate that Totten Glacier and, by extension, the Aurora Subglacial Basin are vulnerable to MCDW that has been observed on the nearby Sabrina Coast continental shelf by multiple shipborne expeditions beginning in 1996.
Population connectivity of deep-sea corals: Chapter 12
Morrison, Cheryl L.; Baco, Amy; Nizinski, Martha S.; Coykendall, D. Katharine; Demopoulos, Amanda W. J.; Cho, Walter; Shank, Tim
2015-01-01
Identifying the scale of dispersal among habitats has been a challenge in marine ecology for decades (Grantham et al., 2003; Kinlan & Gaines, 2003; Hixon, 2011). Unlike terrestrial habitats in which barriers to dispersal may be obvious (e.g. mountain ranges, rivers), few absolute barriers to dispersal are recognizable in the sea. Additionally, most marine species have complex life cycles in which juveniles are more mobile than adults. As such, the dynamics of populations may involve processes in distant habitats that are coupled by a transport mechanism. Studies of population connectivity try to quantify the transport, or dispersal of individuals, among geographically separated populations. For benthic marine species, such as corals and demersal fishes, colonization of new populations occurs primarily by dispersal of larvae (Figure 1; Shank, 2010). Successful dispersal and recruitment, followed by maturation and reproduction of these new migrants ensures individuals contribute to the gene pool (Hedgecock, 2007). Thus, successful dispersal links and cohesively maintains spatially separated sub-populations. At shorter time scales (10-100s years), connectivity regulates community structure by influencing the genetic composition, diversity and demographic stability of the population, whereas at longer time scales (1000s years), geographic distributions are affected (McClain and Hardy, 2010). Alternatively, populations may become extinct or speciation may occur if connectivity ceases (Cowen et al., 2007). Therefore, the genetic exchange of individuals between populations is fundamental to the short-term resilience and long-term maintenance of the species. However, for the vast majority of marine species, population connectivity remains poorly understood.
NASA Astrophysics Data System (ADS)
Moulopoulos, K.
2015-06-01
A quantum system that lies nearby a magnetic or time-varying electric field region, and that is under periodic boundary conditions parallel to the interface, is shown to exhibit a "hidden" Aharonov-Bohm effect (magnetic or electric), caused by fluxes that are not enclosed by, but are merely neighboring to our system - its origin being the absence of magnetic monopoles in 3D space (with corresponding spacetime generalizations). Novel possibilities then arise, where a field-free system can be dramatically affected by manipulating fields in an adjacent or even distant land, provided that these nearby fluxes are not quantized (i.e. they are fractional or irrational parts of the flux quantum). Topological effects (such as Quantum Hall types of behaviors) can therefore be induced from outside our system (that is always field-free and can even reside in simply-connected space). Potential novel applications are outlined, and exotic consequences in solid state physics are pointed out (i.e. the possibility of field-free quantum periodic systems that violate Bloch's theorem), while formal analogies with certain high energy physics phenomena and with some rather under-explored areas in mechanics and thermodynamics are noted.
Wet periods in northeastern Brazil over the past 210 kyr linked to distant climate anomalies.
Wang, Xianfeng; Auler, Augusto S; Edwards, R Lawrence; Cheng, Hai; Cristalli, Patricia S; Smart, Peter L; Richards, David A; Shen, Chuan-Chou
2004-12-09
The tropics are the main source of the atmosphere's sensible and latent heat, and water vapour, and are therefore important for reconstructions of past climate. But long, accurately dated records of southern tropical palaeoclimate, which would allow the establishment of climatic connections to distant regions, have not been available. Here we present a 210,000-year (210-kyr) record of wet periods in tropical northeastern Brazil--a region that is currently semi-arid. The record is obtained from speleothems and travertine deposits that are accurately dated using the U/Th method. We find wet periods that are synchronous with periods of weak East Asian summer monsoons, cold periods in Greenland, Heinrich events in the North Atlantic and periods of decreased river runoff to the Cariaco basin. We infer that the wet periods may be explained with a southward displacement of the Intertropical Convergence Zone. This widespread synchroneity of climate anomalies suggests a relatively rapid global reorganization of the ocean-atmosphere system. We conclude that the wet periods probably affected rainforest distribution, as plant fossils show that forest expansion occurred during these intermittent wet intervals, and opened a forest corridor between the Amazonian and Atlantic rainforests.
LADUMA: Looking At the Distant Universe with the MeerKAT Array
NASA Astrophysics Data System (ADS)
Baker, Andrew J.; Blyth, Sarah; Holwerda, Benne W.; LADUMA team
2018-01-01
The cosmic evolution of galaxies' neutral atomic gas content is a major science driver for the Square Kilometre Array (SKA), as well as for its Australian (ASKAP) and South African (MeerKAT) precursors. Among the HI surveys planned for ASKAP and MeerKAT, the deepest and narrowest tier of the "wedding cake" will be defined by the approved 3424-hour Looking At the Distant Universe with the MeerKAT Array (LADUMA) survey, which will probe HI in emission within a single "cosmic vuvuzela" that extends to z = 1.4, when the universe was only a third of its present age. Through a combination of individual and stacked detections (the latter relying on extensive multiwavelength studies of the survey's target field), LADUMA will study the redshift evolution of the baryonic Tully-Fisher relation and the cosmic HI density, the variation of the HI mass function with redshift and environment, and the connection between HI content and the properties of galaxies' stars (mass, age, etc.). The survey will also build a sample of OH megamaser detections that can be used to trace the cosmic merger history. This talk will introduce the science potential of LADUMA and plans for its execution starting in 2018.
Inflammatory Mechanisms Linking Periodontal Diseases to Cardiovascular Diseases
Schenkein, Harvey A.; Loos, Bruno G.
2015-01-01
Aims In this paper, inflammatory mechanisms that link periodontal diseases to cardiovascular diseases (CVD) are reviewed. Materials and Methods and Results This paper is a literature review. Studies in the literature implicate a number of possible mechanisms that could be responsible for increased inflammatory responses in atheromatous lesions due to periodontal infections. These include increased systemic levels of inflammatory mediators stimulated by bacteria and their products at sites distant from the oral cavity, elevated thrombotic and hemostatic markers that promote a prothrombotic state and inflammation, cross-reactive systemic antibodies that promote inflammation and interact with the atheroma, promotion of dyslipidemia with consequent increases in proinflammatory lipid classes and subclasses, and common genetic susceptibility factors present in both disease leading to increased inflammatory responses. Conclusions Such mechanisms may be thought to act in concert to increase systemic inflammation in periodontal disease and to promote or exacerbate atherogenesis. However, proof that the increase in systemic inflammation attributable to periodontitis impacts inflammatory responses during atheroma development, thrombotic events, or myocardial infarction or stroke is lacking. PMID:23627334
Young, Emma F; Belchier, Mark; Hauser, Lorenz; Horsburgh, Gavin J; Meredith, Michael P; Murphy, Eugene J; Pascoal, Sonia; Rock, Jennifer; Tysklind, Niklas; Carvalho, Gary R
2015-06-01
Understanding the key drivers of population connectivity in the marine environment is essential for the effective management of natural resources. Although several different approaches to evaluating connectivity have been used, they are rarely integrated quantitatively. Here, we use a 'seascape genetics' approach, by combining oceanographic modelling and microsatellite analyses, to understand the dominant influences on the population genetic structure of two Antarctic fishes with contrasting life histories, Champsocephalus gunnari and Notothenia rossii. The close accord between the model projections and empirical genetic structure demonstrated that passive dispersal during the planktonic early life stages is the dominant influence on patterns and extent of genetic structuring in both species. The shorter planktonic phase of C. gunnari restricts direct transport of larvae between distant populations, leading to stronger regional differentiation. By contrast, geographic distance did not affect differentiation in N. rossii, whose longer larval period promotes long-distance dispersal. Interannual variability in oceanographic flows strongly influenced the projected genetic structure, suggesting that shifts in circulation patterns due to climate change are likely to impact future genetic connectivity and opportunities for local adaptation, resilience and recovery from perturbations. Further development of realistic climate models is required to fully assess such potential impacts.
The giant acoustic atom - a single quantum system with a deterministic time delay
NASA Astrophysics Data System (ADS)
Guo, Lingzhen; Grimsmo, Arne; Frisk Kockum, Anton; Pletyukhov, Mikhail; Johansson, Göran
2017-04-01
We investigate the quantum dynamics of a single transmon qubit coupled to surface acoustic waves (SAWs) via two distant connection points. Since the acoustic speed is five orders of magnitude slower than the speed of light, the travelling time between the two connection points needs to be taken into account. Therefore, we treat the transmon qubit as a giant atom with a deterministic time delay. We find that the spontaneous emission of the system, formed by the giant atom and the SAWs between its connection points, initially follows a polynomial decay law instead of an exponential one, as would be the case for a small atom. We obtain exact analytical results for the scattering properties of the giant atom up to two-phonon processes by using a diagrammatic approach. The time delay gives rise to novel features in the reflection, transmission, power spectra, and second-order correlation functions of the system. Furthermore, we find the short-time dynamics of the giant atom for arbitrary drive strength by a numerically exact method for open quantum systems with a finite-time-delay feedback loop. L. G. acknowledges financial support from Carl-Zeiss Stiftung (0563-2.8/508/2).
Optimal Learning Paths in Information Networks
Rodi, G. C.; Loreto, V.; Servedio, V. D. P.; Tria, F.
2015-01-01
Each sphere of knowledge and information could be depicted as a complex mesh of correlated items. By properly exploiting these connections, innovative and more efficient navigation strategies could be defined, possibly leading to a faster learning process and an enduring retention of information. In this work we investigate how the topological structure embedding the items to be learned can affect the efficiency of the learning dynamics. To this end we introduce a general class of algorithms that simulate the exploration of knowledge/information networks standing on well-established findings on educational scheduling, namely the spacing and lag effects. While constructing their learning schedules, individuals move along connections, periodically revisiting some concepts, and sometimes jumping on very distant ones. In order to investigate the effect of networked information structures on the proposed learning dynamics we focused both on synthetic and real-world graphs such as subsections of Wikipedia and word-association graphs. We highlight the existence of optimal topological structures for the simulated learning dynamics whose efficiency is affected by the balance between hubs and the least connected items. Interestingly, the real-world graphs we considered lead naturally to almost optimal learning performances. PMID:26030508
Microrectenna: A Terahertz Antenna and Rectifier on a Chip
NASA Technical Reports Server (NTRS)
Siegel, Peter
2007-01-01
A microrectenna that would operate at a frequency of 2.5 THz has been designed and partially fabricated. The circuit is intended to be a prototype of an extremely compact device that could be used to convert radio-beamed power to DC to drive microdevices (see Figure 1). The microrectenna (see Figure 2) circuit consists of an antenna, a diode rectifier and a DC output port. The antenna consists of a twin slot array in a conducting ground plane (denoted the antenna ground plane) over an enclosed quarter-wavelength-thick resonant cavity (denoted the reflecting ground plane). The circuit also contains a planar high-frequency low-parasitic Schottky-barrier diode, a low-impedance microstrip transmission line, capacitors, and contact beam leads. The entire 3-D circuit is fabricated monolithically from a single GaAs wafer. The resonant cavity renders the slot radiation pattern unidirectional with a half-power beam width of about 65. A unique metal mesh on the rear of the wafer forms the backplate for the cavity but allows the GaAs to be wet etched from the rear surface of the twin slot antennas and ground plane. The beam leads protrude past the edge of the chip and are used both to mount the microrectenna and to make the DC electrical connection with external circuitry. The antenna ground plane and the components on top of it are formed on a 2- m thick GaAs membrane that is grown in the initial wafer MBE (molecular beam epitaxy) process. The side walls of the antenna cavity are not metal coated and, hence, would cause some loss of power; however, the relatively high permittivity (epsilon=13) of the GaAs keeps the cavity modes well confined, without the usual surface-wave losses associated with thick dielectric substrates. The Schottky-barrier diode has the usual submicron dimensions associated with THz operation and is formed in a mesa process above the antenna ground plane. The diode is connected at the midpoint of a microstrip transmission line, which is formed on 1- m-thick SiO (permittivity of 5) laid down on top of the GaAs membrane. The twin slots are fed in phase by this structure. To prevent radio-frequency (RF) leakage past the slot antennas, low-loss capacitors are integrated into the microstrip transmission line at the edges of the slots. The DC current- carrying lines extend from the outer edges of the capacitors, widen approaching the edges of the chip, and continue past the edges of the chip to become the beam leads used in tacking down the devices. The structure provides a self-contained RF to DC converter that works in the THz range.
A preoperative appliance for a newborn with cleft palate.
Karayazgan, Banu; Gunay, Yumushan; Gurbuzer, Bahadir; Erkan, Mustafa; Atay, Arzu
2009-01-01
Cleft palate is a commonly observed congenital maxillofacial defect. One of the most important problems with clefts is the interference with feeding. An affected infant cannot produce negative pressure in the oral cavity and therefore cannot move the bolus backward to the pharynx. To obtain better nutritional intake prior to surgical correction, a palatal lift obturator is recommended. In this clinical report, a modified technique of obturator fabrication is presented. The new method uses a piece of tulle, a flexible and durable material that is frequently used in theater attire. With the help of this material, the bulb part is connected to the plate as a labile piece, and this connection acts like a natural velopharyngeal extension. Additionally, because of the softer property of the silicone elastomer, the posterior pharyngeal wall is less irritated.
Borton, David A.; Song, Yoon-Kyu; Patterson, William R.; Bull, Christopher W.; Park, Sunmee; Laiwalla, Farah; Donoghue, John P.; Nurmikko, Arto V.
2013-01-01
A multitude of neuroengineering challenges exist today in creating practical, chronic multichannel neural recording systems for primate research and human clinical application. Specifically, a) the persistent wired connections limit patient mobility from the recording system, b) the transfer of high bandwidth signals to external (even distant) electronics normally forces premature data reduction, and c) the chronic susceptibility to infection due to the percutaneous nature of the implants all severely hinder the success of neural prosthetic systems. Here we detail one approach to overcome these limitations: an entirely implantable, wirelessly communicating, integrated neural recording microsystem, dubbed the Brain Implantable Chip (BIC). PMID:19964128
Study and Application of Remote Data Moving Transmission under the Network Convergence
NASA Astrophysics Data System (ADS)
Zhiguo, Meng; Du, Zhou
The data transmission is an important problem in remote applications. Advance of network convergence has help to select and use data transmission model. The embedded system and data management platform is a key of the design. With communication module, interface technology and the transceiver which has independent intellectual property rights connected broadband network and mobile network seamlessly. Using the distribution system of mobile base station to realize the wireless transmission, using public networks to implement the data transmission, making the distant information system break through area restrictions and realizing transmission of the moving data, it has been fully recognized in long-distance medical care applications.
Opto-mechanical lab-on-fibre seismic sensors detected the Norcia earthquake.
Pisco, Marco; Bruno, Francesco Antonio; Galluzzo, Danilo; Nardone, Lucia; Gruca, Grzegorz; Rijnveld, Niek; Bianco, Francesca; Cutolo, Antonello; Cusano, Andrea
2018-04-27
We have designed and developed lab-on-fibre seismic sensors containing a micro-opto-mechanical cavity on the fibre tip. The mechanical cavity is designed as a double cantilever suspended on the fibre end facet and connected to a proof mass to tune its response. Ground acceleration leads to displacement of the cavity length, which in turn can be remotely detected using an interferometric interrogation technique. After the sensors characterization, an experimental validation was conducted at the Italian National Institute of Geophysics and Volcanology (INGV), which is responsible for seismic surveillance over the Italian country. The fabricated sensors have been continuously used for long periods to demonstrate their effectiveness as seismic accelerometer sensors. During the tests, fibre optic seismic accelerometers clearly detected the seismic sequence that culminated in the severe Mw6.5 Norcia earthquake that struck central Italy on October 30, 2016. The seismic data provided by the optical sensors were analysed by specialists at the INGV. The wave traces were compared with state-of-the-art traditional sensors typically incorporated into the INGV seismic networks. The comparison verifies the high fidelity of the optical sensors in seismic wave detection, indicating their suitability for a novel class of seismic sensors to be employed in practical scenarios.
Detection of hydrogen cyanide from oral anaerobes by cavity ring down spectroscopy
Chen, Wen; Roslund, Kajsa; Fogarty, Christopher L.; Pussinen, Pirkko J.; Halonen, Lauri; Groop, Per-Henrik; Metsälä, Markus; Lehto, Markku
2016-01-01
Hydrogen cyanide (HCN) has been recognized as a potential biomarker for non-invasive diagnosis of Pseudomonas aeruginosa infection in the lung. However, the oral cavity is a dominant production site for exhaled HCN and this contribution can mask the HCN generated in the lung. It is thus important to understand the sources of HCN production in the oral cavity. By screening of oral anaerobes for HCN production, we observed that the genus of Porphyromonas, Prevotella and Fusobacterium generated low levels of HCN in vitro. This is the first study to show that oral anaerobes are capable of producing HCN in vitro. Further investigations were conducted on the species of P. gingivalis and we successfully detected HCN production (0.9–10.9 ppb) in the headspace of three P. gingivalis reference strains (ATCC 33277, W50 and OMG 434) and one clinical isolate. From P. gingivalis ATCC 33277 and W50, a strong correlation between HCN and CO2 concentrations (rs = 0.89, p < 0.001) was observed, indicating that the HCN production of P. gingivalis might be connected with the bacterial metabolic activity. These results indicate that our setup could be widely applied to the screening of in vitro HCN production by both aerobic and anaerobic bacteria. PMID:26940198
Liu, Ning; Gocalinska, Agnieszka; Justice, John; Gity, Farzan; Povey, Ian; McCarthy, Brendan; Pemble, Martyn; Pelucchi, Emanuele; Wei, Hong; Silien, Christophe; Xu, Hongxing; Corbett, Brian
2016-12-14
Hybrid plasmonic lasers provide deep subwavelength optical confinement, strongly enhanced light-matter interaction and together with nanoscale footprint promise new applications in optical communication, biosensing, and photolithography. The subwavelength hybrid plasmonic lasers reported so far often use bottom-up grown nanowires, nanorods, and nanosquares, making it difficult to integrate these devices into industry-relevant high density plasmonic circuits. Here, we report the first experimental demonstration of AlGaInP based, red-emitting hybrid plasmonic lasers at room temperature using lithography based fabrication processes. Resonant cavities with deep subwavelength 2D and 3D mode confinement of λ 2 /56 and λ 3 /199, respectively, are demonstrated. A range of cavity geometries (waveguides, rings, squares, and disks) show very low lasing thresholds of 0.6-1.8 mJ/cm 2 with wide gain bandwidth (610 nm-685 nm), which are attributed to the heterogeneous geometry of the gain material, the optimized etching technique, and the strong overlap of the gain material with the plasmonic modes. Most importantly, we establish the connection between mode confinements and enhanced absorption and stimulated emission, which plays critical roles in maintaining low lasing thresholds at extremely small hybrid plasmonic cavities. Our results pave the way for the further integration of dense arrays of hybrid plasmonic lasers with optical and electronic technology platforms.
Detection of hydrogen cyanide from oral anaerobes by cavity ring down spectroscopy
NASA Astrophysics Data System (ADS)
Chen, Wen; Roslund, Kajsa; Fogarty, Christopher L.; Pussinen, Pirkko J.; Halonen, Lauri; Groop, Per-Henrik; Metsälä, Markus; Lehto, Markku
2016-03-01
Hydrogen cyanide (HCN) has been recognized as a potential biomarker for non-invasive diagnosis of Pseudomonas aeruginosa infection in the lung. However, the oral cavity is a dominant production site for exhaled HCN and this contribution can mask the HCN generated in the lung. It is thus important to understand the sources of HCN production in the oral cavity. By screening of oral anaerobes for HCN production, we observed that the genus of Porphyromonas, Prevotella and Fusobacterium generated low levels of HCN in vitro. This is the first study to show that oral anaerobes are capable of producing HCN in vitro. Further investigations were conducted on the species of P. gingivalis and we successfully detected HCN production (0.9-10.9 ppb) in the headspace of three P. gingivalis reference strains (ATCC 33277, W50 and OMG 434) and one clinical isolate. From P. gingivalis ATCC 33277 and W50, a strong correlation between HCN and CO2 concentrations (rs = 0.89, p < 0.001) was observed, indicating that the HCN production of P. gingivalis might be connected with the bacterial metabolic activity. These results indicate that our setup could be widely applied to the screening of in vitro HCN production by both aerobic and anaerobic bacteria.
Detection of hydrogen cyanide from oral anaerobes by cavity ring down spectroscopy.
Chen, Wen; Roslund, Kajsa; Fogarty, Christopher L; Pussinen, Pirkko J; Halonen, Lauri; Groop, Per-Henrik; Metsälä, Markus; Lehto, Markku
2016-03-04
Hydrogen cyanide (HCN) has been recognized as a potential biomarker for non-invasive diagnosis of Pseudomonas aeruginosa infection in the lung. However, the oral cavity is a dominant production site for exhaled HCN and this contribution can mask the HCN generated in the lung. It is thus important to understand the sources of HCN production in the oral cavity. By screening of oral anaerobes for HCN production, we observed that the genus of Porphyromonas, Prevotella and Fusobacterium generated low levels of HCN in vitro. This is the first study to show that oral anaerobes are capable of producing HCN in vitro. Further investigations were conducted on the species of P. gingivalis and we successfully detected HCN production (0.9-10.9 ppb) in the headspace of three P. gingivalis reference strains (ATCC 33277, W50 and OMG 434) and one clinical isolate. From P. gingivalis ATCC 33277 and W50, a strong correlation between HCN and CO2 concentrations (rs = 0.89, p < 0.001) was observed, indicating that the HCN production of P. gingivalis might be connected with the bacterial metabolic activity. These results indicate that our setup could be widely applied to the screening of in vitro HCN production by both aerobic and anaerobic bacteria.
A photonic link for donor spin qubits in silicon
NASA Astrophysics Data System (ADS)
Simmons, Stephanie
Atomically identical donor spin qubits in silicon offer excellent native quantum properties, which match or outperform many qubit rivals. To scale up such systems it would be advantageous to connect silicon donor spin qubits in a cavity-QED architecture. Many proposals in this direction introduce strong electric dipole interactions to the otherwise largely isolated spin qubit ground state in order to couple to superconducting cavities. Here I present an alternative approach, which uses the built-in strong electric dipole (optical) transitions of singly-ionized double donors in silicon. These donors, such as chalcogen donors S +, Se + and Te +, have the same ground-state spin Hamiltonians as shallow donors yet offer mid-gap binding energies and mid-IR optical access to excited orbital states. This photonic link is spin-selective which could be harnessed to measure and couple donor qubits using photonic cavity-QED. This approach should be robust to device environments with variable strains and electric fields, and will allow for CMOS- compatible, bulk-like, spatially separated donor qubit placement, optical parity measurements, and 4.2K operation. I will present preliminary data in support of this approach, including 4.2K optical initialization/readout in Earth's magnetic field, where long T1 and T2 times have been measured.
Bellomo, Facundo J.; Rosales, Iván; del Castillo, Luis F.; Sánchez, Ricardo; Turon, Pau
2018-01-01
Endoluminal vacuum-assisted closure (E-VAC) is a promising therapy to treat anastomotic leakages of the oesophagus and bowel which are associated with high morbidity and mortality rates. An open-pore polyurethane foam is introduced into the leakage cavity and connected to a device that applies a suction pressure to accelerate the closure of the defect. Computational analysis of this healing process can advance our understanding of the biomechanical mechanisms at play. To this aim, we use a dual-stage finite-element analysis in which (i) the structural problem addresses the cavity reduction caused by the suction and (ii) a new constitutive formulation models tissue healing via permanent deformations coupled to a stiffness increase. The numerical implementation in an in-house code is described and a qualitative example illustrates the basic characteristics of the model. The computational model successfully reproduces the generic closure of an anastomotic leakage cavity, supporting the hypothesis that suction pressure promotes healing by means of the aforementioned mechanisms. However, the current framework needs to be enriched with empirical data to help advance device designs and treatment guidelines. Nonetheless, this conceptual study confirms that computational analysis can reproduce E-VAC of anastomotic leakages and establishes the bases for better understanding the mechanobiology of anastomotic defect healing. PMID:29515846
Louri, A; Furlonge, S; Neocleous, C
1996-12-10
A prototype of a novel topology for scaleable optical interconnection networks called the optical multi-mesh hypercube (OMMH) is experimentally demonstrated to as high as a 150-Mbit/s data rate (2(7) - 1 nonreturn-to-zero pseudo-random data pattern) at a bit error rate of 10(-13)/link by the use of commercially available devices. OMMH is a scaleable network [Appl. Opt. 33, 7558 (1994); J. Lightwave Technol. 12, 704 (1994)] architecture that combines the positive features of the hypercube (small diameter, connectivity, symmetry, simple routing, and fault tolerance) and the mesh (constant node degree and size scaleability). The optical implementation method is divided into two levels: high-density local connections for the hypercube modules, and high-bit-rate, low-density, long connections for the mesh links connecting the hypercube modules. Free-space imaging systems utilizing vertical-cavity surface-emitting laser (VCSEL) arrays, lenslet arrays, space-invariant holographic techniques, and photodiode arrays are demonstrated for the local connections. Optobus fiber interconnects from Motorola are used for the long-distance connections. The OMMH was optimized to operate at the data rate of Motorola's Optobus (10-bit-wide, VCSEL-based bidirectional data interconnects at 150 Mbits/s). Difficulties encountered included the varying fan-out efficiencies of the different orders of the hologram, misalignment sensitivity of the free-space links, low power (1 mW) of the individual VCSEL's, and noise.
2011-01-01
Background Prognostic factors in predicting occult lymph node metastasis in patients with head and neck squamous-cell carcinoma (HNSCC) are necessary to improve the results of the sentinel lymph node procedure in this tumour type. The E-Cadherin glycoprotein is an intercellular adhesion molecule in epithelial cells, which plays an important role in establishing and maintaining intercellular connections. Objectives To determine the value of the molecular marker E-Cadherin in predicting regional metastatic disease. Methods E-Cadherin expression in tumour tissue of 120 patients with HNSCC of the oral cavity and oropharynx were evaluated using the tissue microarray technique. 110 tumours were located in the oral cavity (91.7%; mostly tongue), 10 tumours in the oropharynx (8.3%). Intensity of E-Cadherin expression was quantified by the Intensity Reactivity Score (IRS). These results were correlated with the lymph node status of biopsied sentinel lymph nodes. Univariate and multivariate analysis was used to determine statistical significance. Results pT-stage, gender, tumour side and location did not correlate with lymph node metastasis. Differentiation grade (p = 0.018) and down regulation of E-Cadherin expression significantly correlate with positive lymph node status (p = 0.005) in univariate and multivariate analysis. Conclusion These data suggest that loss of E-cadherin expression is associated with increased lymhogeneous metastasis of HNSCC. E-cadherin immunohistochemistry may be used as a predictor for lymph node metastasis in squamous cell carcinoma of the oral cavity and oropharynx. Level of evidence: 2b PMID:21639893
NASA Astrophysics Data System (ADS)
Woodcock, D. C.; Lane, S. J.; Gilbert, J. S.
2017-07-01
Subglacial explosive volcanism generates hazards that result from magma-ice interaction, including large flow rate meltwater flooding and fine-grained volcanic ash. We consider eruptions where subglacial cavities produced by ice melt during eruption establish a connection to the atmosphere along the base of the ice sheet that allows accumulated meltwater to drain. The resulting reduction of pressure initiates or enhances explosive phreatomagmatic volcanism within a steam-filled cavity with pyroclast impingement on the cavity roof. Heat transfer rates to melt ice in such a system have not, to our knowledge, been assessed previously. To study this system, we take an experimental approach to gain insight into the heat transfer processes and to quantify ice melt rates. We present the results of a series of analogue laboratory experiments in which a jet of steam, air, and sand at approximately 300°C impinged on the underside of an ice block. A key finding was that as the steam to sand ratio was increased, behavior ranged from predominantly horizontal ice melting to predominantly vertical melting by a mobile slurry of sand and water. For the steam to sand ratio that matches typical steam to pyroclast ratios during subglacial phreatomagmatic eruptions at 300°C, we observed predominantly vertical melting with upward ice melt rates of 1.5 mm s-1, which we argue is similar to that within the volcanic system. This makes pyroclast-ice heat transfer an important contributing ice melt mechanism under drained, low-pressure conditions that may precede subaerial explosive volcanism on sloping flanks of glaciated volcanoes.
Electrostatic and Structural Bases of Fe2+ Translocation through Ferritin Channels*
Chandramouli, Balasubramanian; Bernacchioni, Caterina; Di Maio, Danilo; Turano, Paola; Brancato, Giuseppe
2016-01-01
Ferritin molecular cages are marvelous 24-mer supramolecular architectures that enable massive iron storage (>2000 iron atoms) within their inner cavity. This cavity is connected to the outer environment by two channels at C3 and C4 symmetry axes of the assembly. Ferritins can also be exploited as carriers for in vivo imaging and therapeutic applications, owing to their capability to effectively protect synthetic non-endogenous agents within the cage cavity and deliver them to targeted tissue cells without stimulating adverse immune responses. Recently, X-ray crystal structures of Fe2+-loaded ferritins provided important information on the pathways followed by iron ions toward the ferritin cavity and the catalytic centers within the protein. However, the specific mechanisms enabling Fe2+ uptake through wild-type and mutant ferritin channels is largely unknown. To shed light on this question, we report extensive molecular dynamics simulations, site-directed mutagenesis, and kinetic measurements that characterize the transport properties and translocation mechanism of Fe2+ through the two ferritin channels, using the wild-type bullfrog Rana catesbeiana H′ protein and some of its variants as case studies. We describe the structural features that determine Fe2+ translocation with atomistic detail, and we propose a putative mechanism for Fe2+ transport through the channel at the C3 symmetry axis, which is the only iron-permeable channel in vertebrate ferritins. Our findings have important implications for understanding how ion permeation occurs, and further how it may be controlled via purposely engineered channels for novel biomedical applications based on ferritin. PMID:27756844
Electrostatic and Structural Bases of Fe2+ Translocation through Ferritin Channels.
Chandramouli, Balasubramanian; Bernacchioni, Caterina; Di Maio, Danilo; Turano, Paola; Brancato, Giuseppe
2016-12-02
Ferritin molecular cages are marvelous 24-mer supramolecular architectures that enable massive iron storage (>2000 iron atoms) within their inner cavity. This cavity is connected to the outer environment by two channels at C3 and C4 symmetry axes of the assembly. Ferritins can also be exploited as carriers for in vivo imaging and therapeutic applications, owing to their capability to effectively protect synthetic non-endogenous agents within the cage cavity and deliver them to targeted tissue cells without stimulating adverse immune responses. Recently, X-ray crystal structures of Fe 2+ -loaded ferritins provided important information on the pathways followed by iron ions toward the ferritin cavity and the catalytic centers within the protein. However, the specific mechanisms enabling Fe 2+ uptake through wild-type and mutant ferritin channels is largely unknown. To shed light on this question, we report extensive molecular dynamics simulations, site-directed mutagenesis, and kinetic measurements that characterize the transport properties and translocation mechanism of Fe 2+ through the two ferritin channels, using the wild-type bullfrog Rana catesbeiana H' protein and some of its variants as case studies. We describe the structural features that determine Fe 2+ translocation with atomistic detail, and we propose a putative mechanism for Fe 2+ transport through the channel at the C3 symmetry axis, which is the only iron-permeable channel in vertebrate ferritins. Our findings have important implications for understanding how ion permeation occurs, and further how it may be controlled via purposely engineered channels for novel biomedical applications based on ferritin. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
A Diverticular ‘Pain in the Bottom’
Bardhan, Suchi K; Morgan, Emma; Daniels, Ian R; Mortensen, Neil J
2006-01-01
This is the case of a 40-year-old man with a gluteal abscess as the first presentation of diverticular disease. As well as the unusual site, imaging revealed the lack of a connective tract between the abscess and the abdominal cavity or retroperitoneum. In addition, a lack of gastrointestinal symptoms made this case very unusual. Hence, this highlights the need for a high index of clinical suspicion when the usual clinical pointers that guide to the diagnosis of diverticulitis are absent. PMID:16834842
A diverticular 'pain in the bottom'.
Bardhan, Suchi K; Morgan, Emma; Daniels, Ian R; Mortensen, Neil J
2006-07-01
This is the case of a 40-year-old man with a gluteal abscess as the first presentation of diverticular disease. As well as the unusual site, imaging revealed the lack of a connective tract between the abscess and the abdominal cavity or retroperitoneum. In addition, a lack of gastrointestinal symptoms made this case very unusual. Hence, this highlights the need for a high index of clinical suspicion when the usual clinical pointers that guide to the diagnosis of diverticulitis are absent.
Thermoelectric energy harvesting with quantum dots
NASA Astrophysics Data System (ADS)
Sothmann, Björn; Sánchez, Rafael; Jordan, Andrew N.
2015-01-01
We review recent theoretical work on thermoelectric energy harvesting in multi-terminal quantum-dot setups. We first discuss several examples of nanoscale heat engines based on Coulomb-coupled conductors. In particular, we focus on quantum dots in the Coulomb-blockade regime, chaotic cavities and resonant tunneling through quantum dots and wells. We then turn toward quantum-dot heat engines that are driven by bosonic degrees of freedom such as phonons, magnons and microwave photons. These systems provide interesting connections to spin caloritronics and circuit quantum electrodynamics.
[Bonding of ceramic onlays. The effect on contour form].
Perelmuter, S; Liger, F
1990-01-01
Ceramic onlays have come into much wider use and experience has led to gradual modification of preparation contours. The aim was to improve two complementary aspects, aesthetics and mechanical strength. The use of ceramics to rebuild cusps enhances the structures' mimetic effect and mechanical qualities. If an isthmus exists connecting the occlusal and proximal cavities, it must be enlarged; if not, none must be created. The use of bonded ceramic overlays offers an original therapeutic result. They are indicated in order to even out occlusal patterns.
Chip Scale, Ultra Sensitive Opto Mechanical Acceleration and Force Sensors
2017-12-01
an accelerometer of the same mechanical design as that studied in part A. and shown in Fig. 3. One side of the zipper optical cavity is connected to...Ref. [13]. “Endevco 752A13” is Ref. [30]. “Zipper” is our own work on zipper photonic crystals from Ref. [31]. II Accelerometer Noise and Design ...limit, the shot noise of the light field also imparts a force on , and cause motion of, the mechanical resonator. The acceleration PSD due to back-action
Fibre Optic Connections And Method For Using Same
Chan, Benson; Cohen, Mitchell S.; Fortier, Paul F.; Freitag, Ladd W.; Hall, Richard R.; Johnson, Glen W.; Lin, How Tzu; Sherman, John H.
2004-03-30
A package is described that couples a twelve channel wide fiber optic cable to a twelve channel Vertical Cavity Surface Emitting Laser (VCSEL) transmitter and a multiple channel Perpendicularly Aligned Integrated Die (PAID) receiver. The package allows for reduction in the height of the assembly package by vertically orienting certain dies parallel to the fiber optic cable and horizontally orienting certain other dies. The assembly allows the vertically oriented optoelectronic dies to be perpendicularly attached to the horizontally oriented laminate via a flexible circuit.
Kandala, Sridhar; Nolan, Dan; Laumann, Timothy O.; Power, Jonathan D.; Adeyemo, Babatunde; Harms, Michael P.; Petersen, Steven E.; Barch, Deanna M.
2016-01-01
Abstract Like all resting-state functional connectivity data, the data from the Human Connectome Project (HCP) are adversely affected by structured noise artifacts arising from head motion and physiological processes. Functional connectivity estimates (Pearson's correlation coefficients) were inflated for high-motion time points and for high-motion participants. This inflation occurred across the brain, suggesting the presence of globally distributed artifacts. The degree of inflation was further increased for connections between nearby regions compared with distant regions, suggesting the presence of distance-dependent spatially specific artifacts. We evaluated several denoising methods: censoring high-motion time points, motion regression, the FMRIB independent component analysis-based X-noiseifier (FIX), and mean grayordinate time series regression (MGTR; as a proxy for global signal regression). The results suggest that FIX denoising reduced both types of artifacts, but left substantial global artifacts behind. MGTR significantly reduced global artifacts, but left substantial spatially specific artifacts behind. Censoring high-motion time points resulted in a small reduction of distance-dependent and global artifacts, eliminating neither type. All denoising strategies left differences between high- and low-motion participants, but only MGTR substantially reduced those differences. Ultimately, functional connectivity estimates from HCP data showed spatially specific and globally distributed artifacts, and the most effective approach to address both types of motion-correlated artifacts was a combination of FIX and MGTR. PMID:27571276
Development of brain-wide connectivity architecture in awake rats.
Ma, Zilu; Ma, Yuncong; Zhang, Nanyin
2018-08-01
Childhood and adolescence are both critical developmental periods, evidenced by complex neurophysiological changes the brain undergoes and high occurrence rates of neuropsychiatric disorders during these periods. Despite substantial progress in elucidating the developmental trajectories of individual neural circuits, our knowledge of developmental changes of whole-brain connectivity architecture in animals is sparse. To fill this gap, here we longitudinally acquired rsfMRI data in awake rats during five developmental stages from juvenile to adulthood. We found that the maturation timelines of brain circuits were heterogeneous and system specific. Functional connectivity (FC) tended to decrease in subcortical circuits, but increase in cortical circuits during development. In addition, the developing brain exhibited hemispheric functional specialization, evidenced by reduced inter-hemispheric FC between homotopic regions, and lower similarity of region-to-region FC patterns between the two hemispheres. Finally, we showed that whole-brain network development was characterized by reduced clustering (i.e. local communication) but increased integration (distant communication). Taken together, the present study has systematically characterized the development of brain-wide connectivity architecture from juvenile to adulthood in awake rats. It also serves as a critical reference point for understanding circuit- and network-level changes in animal models of brain development-related disorders. Furthermore, FC data during brain development in awake rodents contain high translational value and can shed light onto comparative neuroanatomy. Copyright © 2018 Elsevier Inc. All rights reserved.
Apaza-Bedoya, K; Tarce, M; Benfatti, C A M; Henriques, B; Mathew, M T; Teughels, W; Souza, J C M
2017-12-01
Two-piece implant systems are mainly used in oral implantology involving an osseointegrated implant connected to an abutment, which supports prosthetic structures. It is well documented that the presence of microgaps, biofilms and oral fluids at the implant-abutment connection can cause mechanical and biological complications. The aim of this review paper was to report the degradation at the implant-abutment connection by wear and corrosion processes taking place in the oral cavity. Most of the retrieved studies evaluated the wear and corrosion (tribocorrosion) of titanium-based materials used for implants and abutments in artificial saliva. Electrochemical and wear tests together with microscopic techniques were applied to validate the tribocorrosion behavior of the surfaces. A few studies inspected the wear on the inner surfaces of the implant connection as a result of fatigue or removal of abutments. The studies reported increased microgaps after fatigue tests. In addition, data suggest that micromovements occurring at the contacting surfaces can increase the wear of the inner surfaces of the connection. Biofilms and/or glycoproteins act as lubricants, although they can also amplify the corrosion of the surfaces. Consequently, loosening of the implant-abutment connection can take place during mastication. In addition, wear and corrosion debris such as ions and micro- and nanoparticles released into the surrounding tissues can stimulate peri-implant inflammation that can lead to pathologic bone resorption. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Cavalcante, Geórgenes H; Feary, David A; Burt, John A
2016-04-30
Using long-term oceanographic surveys and a 3-D hydrodynamic model we show that localized peak winds (known as shamals) cause fluctuation in water current speed and direction, and substantial oscillations in sea-bottom salinity and temperature in the southern Persian/Arabian Gulf. Results also demonstrate that short-term shamal winds have substantial impacts on oceanographic processes along the southern Persian/Arabian Gulf coastline, resulting in formation of large-scale (52 km diameter) eddies extending from the coast of the United Arab Emirates (UAE) to areas near the off-shore islands of Iran. Such eddies likely play an important role in transporting larvae from well-developed reefs of the off-shore islands to the degraded reef systems of the southern Persian/Arabian Gulf, potentially maintaining genetic and ecological connectivity of these geographically distant populations and enabling enhanced recovery of degraded coral communities in the UAE. Copyright © 2015 Elsevier Ltd. All rights reserved.
Mao, Zhengfa; Ma, Xiaoyan; Rong, Yefei; Cui, Lei; Wang, Xuqing; Wu, Wenchuan; Zhang, Jianxin; Jin, Dayong
2011-01-01
Local invasion and distant metastasis are difficult problems for surgical intervention and treatment in gastric cancer. Connective tissue growth factor (CTGF/CCN2) was considered to have an important role in this process. In this study, we demonstrated that expression of CTGF was significantly upregulated in clinical tissue samples of gastric carcinoma (GC) samples. Forced expression of CTGF in AGS GC cells promoted their migration in culture and significantly increased tumor metastasis in nude mice, whereas RNA interference-mediated knockdown of CTGF in GC cells significantly inhibited cell migration in vitro. We disclose that CTGF downregulated the expression of E-cadherin through activation of the nuclear factor-κappa B (NF-κB) pathway. The effects of CTGF in GC cells were abolished by dominant negative IκappaB. Collectively, these data reported here demonstrate CTGF could modulate the NF-κappaB pathway and perhaps be a promising therapeutic target for gastric cancer invasion and metastasis. © 2010 Japanese Cancer Association.
Rodent Zic Genes in Neural Network Wiring.
Herrera, Eloísa
2018-01-01
The formation of the nervous system is a multistep process that yields a mature brain. Failure in any of the steps of this process may cause brain malfunction. In the early stages of embryonic development, neural progenitors quickly proliferate and then, at a specific moment, differentiate into neurons or glia. Once they become postmitotic neurons, they migrate to their final destinations and begin to extend their axons to connect with other neurons, sometimes located in quite distant regions, to establish different neural circuits. During the last decade, it has become evident that Zic genes, in addition to playing important roles in early development (e.g., gastrulation and neural tube closure), are involved in different processes of late brain development, such as neuronal migration, axon guidance, and refinement of axon terminals. ZIC proteins are therefore essential for the proper wiring and connectivity of the brain. In this chapter, we review our current knowledge of the role of Zic genes in the late stages of neural circuit formation.
Luminous Infrared Galaxies and the ``Starburst-AGN Connection"
NASA Astrophysics Data System (ADS)
Sanders, D. B.; Kartaltepe, J. S.; Kewley, L. J.; U, Vivian; Yuan, T.; Evans, A. S.; Armus, L.; Mazzarella, J. M.
2009-10-01
Luminous Infrared Galaxies (LIRGs) represent perhaps the most powerful examples of a connection between the fueling of starbursts and active galactic nuclei (AGNs). Major mergers of gas-rich spirals, which are now understood to trigger the majority of LIRGs, drive the bulk of the disk gas into the central kpc of the merger pair, where it provides fuel for both powerful nuclear starbursts and accretion onto a central massive black hole. The combined feedback from starburst and accretion luminosity eventually expels the gas, shutting down nuclear activity and leaving a gas-poor elliptical. Although there is now general agreement on the origin and evolutionary scenario for LIRGs, the detailed time evolution of starburst activity and black hole growth is still not well understood. We review the basic properties of LIRGs as determined from extensive multi-wavelength studies of a complete sample of local objects, and introduce new results from initial observations of fainter more distant LIRGs detected in the Spitzer survey of the HST-COSMOS 2-deg^2 Field.
NASA Technical Reports Server (NTRS)
Henry, Richard C.
1994-01-01
Attachments to this final report include 2 papers connected with the Voyager work: 'Voyager Observations of Dust Scattering Near the Coalsack Nebula' and 'Search for the Intergalactic Medium'. An appendix of 12 one-page write-ups prepared in connection with another program, UVISI, is also included. The one-page write-ups are: (1) Sky survey of UV point sources to 600 times fainter than previous (TD-1) survey; (2) Diffuse galactic light: starlight scattered from dust at high galactic latitude; (3) Optical properties of interstellar grains; (4) Fluorescence of molecular hydrogen in the interstellar medium; (5) Line emission from hot interstellar medium and/or hot halo of galaxy; (6) Integrated light of distant galaxies in the ultraviolet; (7) Intergalactic far-ultraviolet radiation field; (8) Radiation from recombining intergalactic medium; (9) Radiation from re-heating of intergalactic medium following recombination; (10) Radiation from radiative decay of dark matter candidates (neutrino, etc.); (11) Reflectivity of the asteroids in the Ultraviolet; and (12) Zodiacal light.
Contrasting Linguistic and Genetic Origins of the Asian Source Populations of Malagasy
Kusuma, Pradiptajati; Brucato, Nicolas; Cox, Murray P.; Pierron, Denis; Razafindrazaka, Harilanto; Adelaar, Alexander; Sudoyo, Herawati; Letellier, Thierry; Ricaut, François-Xavier
2016-01-01
The Austronesian expansion, one of the last major human migrations, influenced regions as distant as tropical Asia, Remote Oceania and Madagascar, off the east coast of Africa. The identity of the Asian groups that settled Madagascar is particularly mysterious. While language connects Madagascar to the Ma’anyan of southern Borneo, haploid genetic data are more ambiguous. Here, we screened genome-wide diversity in 211 individuals from the Ma’anyan and surrounding groups in southern Borneo. Surprisingly, the Ma’anyan are characterized by a distinct, high frequency genomic component that is not found in Malagasy. This novel genetic layer occurs at low levels across Island Southeast Asia and hints at a more complex model for the Austronesian expansion in this region. In contrast, Malagasy show genomic links to a range of Island Southeast Asian groups, particularly from southern Borneo, but do not have a clear genetic connection with the Ma’anyan despite the obvious linguistic association. PMID:27188237
Complex network analysis of resting-state fMRI of the brain.
Anwar, Abdul Rauf; Hashmy, Muhammad Yousaf; Imran, Bilal; Riaz, Muhammad Hussnain; Mehdi, Sabtain Muhammad Muntazir; Muthalib, Makii; Perrey, Stephane; Deuschl, Gunther; Groppa, Sergiu; Muthuraman, Muthuraman
2016-08-01
Due to the fact that the brain activity hardly ever diminishes in healthy individuals, analysis of resting state functionality of the brain seems pertinent. Various resting state networks are active inside the idle brain at any time. Based on various neuro-imaging studies, it is understood that various structurally distant regions of the brain could be functionally connected. Regions of the brain, that are functionally connected, during rest constitutes to the resting state network. In the present study, we employed the complex network measures to estimate the presence of community structures within a network. Such estimate is named as modularity. Instead of using a traditional correlation matrix, we used a coherence matrix taken from the causality measure between different nodes. Our results show that in prolonged resting state the modularity starts to decrease. This decrease was observed in all the resting state networks and on both sides of the brain. Our study highlights the usage of coherence matrix instead of correlation matrix for complex network analysis.
Success of salvage treatment: a critical appraisal of salvage rates for different subsites of HNSCC.
Matoscevic, Katja; Graf, Nicole; Pezier, Thomas F; Huber, Gerhard F
2014-09-01
Despite advances in interdisciplinary treatment protocols, the chance of cure for recurrent head and neck squamous cell carcinoma (HNSCC) following failed primary therapy is poor and often entails a high morbidity. Recurrence rates vary widely in the literature depending on tumor localization, primary tumor stage, and treatment modality, and only a minority of patients can be salvaged. Historical cohort study. This study valuates the outcomes of patients treated for recurrent squamous cell carcinoma of the larynx, pharynx, and oral cavity in the largest tertiary referral center of Switzerland to find predictors for survival in salvage surgery with curative intent. Included were 176 consecutive patients with recurrent disease after primary curative treatment of HNSCC, in locations mentioned previously. Kaplan-Meier survival analyses with log-rank testing were performed depending on T and N stage, gender, treatment, and location of first relapse to evaluate the impact on overall survival, disease specific survival, and recurrence free survival. Overall successful salvage rates were 49.2% for laryngeal recurrence, 35.1% for oral cavity, 32.7% for oropharyngeal, and a mere 17.4% for hypopharyngeal recurrences. Predictive factors for better outcome were location of recurrence, female gender, lymph node status, and extent of salvage treatment. In case of recurrent disease, laryngeal cancers showed the best salvage rates, whereas in hypopharyngeal relapses, very few patients could be successfully salvaged. Patients therefore should be carefully selected and counseled for salvage treatment according to patient motivation, age, type of previous treatment, surgical resectability, and exclusion of distant recurrence. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.
Liao, Chun-Ta; Chang, Joseph Tung-Chieh; Wang, Hung-Ming; Ng, Shu-Hang; Hsueh, Chuen; Lee, Li-Yu; Lin, Chih-Hung; Chen, I-How; Huang, Shiang-Fu; Cheng, Ann-Joy; Yen, Tzu-Chen
2009-07-15
Survival in oral cavity squamous cell carcinoma (OSCC) depends heavily on locoregional control. In this prospective study, we sought to investigate whether preoperative maximum standardized uptake value of the neck lymph nodes (SUVnodal-max) may predict prognosis in OSCC patients. A total of 120 OSCC patients with pathologically positive lymph nodes were investigated. All subjects underwent a [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) scan within 2 weeks before radical surgery and neck dissection. All patients were followed up for at least 24 months after surgery or until death. Postoperative adjuvant therapy was performed in the presence of pathologic risk factors. Optimal cutoff values of SUVnodal-max were chosen based on 5-year disease-free survival (DFS), disease-specific survival (DSS), and overall survival (OS). Independent prognosticators were identified by Cox regression analysis. The median follow-up for surviving patients was 41 months. The optimal cutoff value for SUVnodal-max was 5.7. Multivariate analyses identified the following independent predictors of poor outcome: SUVnodal-max >or=5.7 for the 5-year neck cancer control rate, distant metastatic rate, DFS, DSS, and extracapsular spread (ECS) for the 5-year DSS and OS. Among ECS patients, the presence of a SUVnodal-max >or=5.7 identified patients with the worst prognosis. A SUVnodal-max of 5.7, either alone or in combination with ECS, is an independent prognosticator for 5-year neck cancer control and survival rates in OSCC patients with pathologically positive lymph nodes.
Pardo, Antonelle; Josse, Thomas; Mespouille, Laetitia; Blankert, Bertrand; Dubois, Philippe; Duez, Pierre
2017-07-01
Molecularly imprinted polymers (MIPs) are composed of specific cavities able to selectively recognise a template molecule. Used as chromatographic sorbents, MIPs may not trap related structures due to the high rigidity of their cross-linking. To improve the capture of quercetin analogues by modulating the synthesis strategy for a quercetin-imprinted polymer (Qu MIP). An additional comonomer bearing a short oligoethylene glycol (OEG) unit was used to prepare a Qu MIP that was compared to a traditional one formulated in a similar fashion, but without the OEG-comonomer. The Qu MIPs were prepared in bead form through fluorocarbon suspension polymerisation. After solid phase extraction (SPE) assessment of their imprinted cavities, the MIPs were evaluated by HPLC for their recognition properties towards quercetin and other polyphenols, including flavonoids, phenolic acids and curcumin. The Qu MIPs were finally SPE-tested on a white onion extract. The incorporation of OEG units modulated the selectivity of the Qu MIP by improving the recognition of quercetin related structures (12-61% increase in the imprinting effect for distant analogues). It also allowed limiting or suppressing non-specific hydrophobic interactions (decrease of about 10% in the rate of quercetin retention on the non-imprinted polymer). The SPE application of the MIP to a white onion extract indicates its interest for the selective extraction of quercetin and its analogues. The OEG-modified Qu MIP appears to be an attractive tool to discover new drug candidates from natural sources by extracting, amongst interfering compounds, structural analogues of quercetin. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Resurgence flows in porous media
NASA Astrophysics Data System (ADS)
Adler, Pierre; Mityushev, Vladimir
2010-05-01
Porous media are generally described by the Darcy equation when the length scales are sufficiently large with respect to the pore scale. This approach is also applicable when the media are heterogeneous, i.e., when permeability varies with space which is the most common case. In addition, real media are very often fractured; for a long time, this complex physical problem has been schematized by the double porosity model devised by Barenblatt. More recently, these fractured media have been addressed with a detailed description of the fractures and of their hydrodynamic interaction with the surrounding porous medium. This approach will be briefly summarized and the main recent progress surveyed (2). There is another situation which occurs frequently in underground studies. One well is connected to a distant well while it is not connected to closer wells. Such a situation can only be understood if there is a direct link between the two connected wells and if this link has little if any hydrodynamic interaction with the porous medium that it crosses. This link can be a fracture or more likely a set of fractures. This phenomenon is called resurgence because of the obvious analogy with rivers which suddenly disappear underground and go out at the ground surface again. Similar ideas have already been developed in other fields. In Physics, random networks limited to nearest neighbors have been recently extended to small world models where distant vertices can be related directly by a link. The electrical testing of porous media by electrical probes located at the walls (electrical tomography) has been used frequently in Geophysics since it is a non-invasive technique; this classical technique corresponds exactly to the situation addressed here from a different perspective. Media with resurgences consist of a double structure (3). The first one which is continuous is described by Darcy law as usual. The second one models the resurgences by capillaries with impermeable walls which relate distant points of the continuous medium. These two structures have already been studied separately in previous works (see (1) and the literature therein). Networks were addressed by graph theory and an extensive literature has been devoted to studies of porous media on the Darcy scale. For sake of simplicity, a simple physical presentation and elementary solutions are first given for one dimensional structures which display unexpected features such as an apparent back flow which goes against the main pressure gradient. Then, a general formulation is proposed which involves some non local aspects. When the sizes of the connection zones between the network and the continuous medium are assumed to be small with respect to any linear size in the continuous medium, analytical solutions are obtained in two or three dimensions for spatially periodic structures which are adequate to model spatially homogenous media. The equivalent permeability of the medium is determined. Some elementary examples are worked out in two and three dimensions. Paradoxical flow patterns are obtained with back flow even with local resurgences (3). Unsteady problems are presently studied. (1) P.M. Adler, Fractures and fracture networks, Kluwer, 1999. (2) P.M. Adler, Porous media. Geometry and transport. Butterworth-Heinemann, Stoneham, Ma, 1992. (3) P. M. Adler, V. Mityushev, Resurgence flows in porous media, Phys. Rev. E 79, 026310, 2009.
Age-related changes in the tooth-bone interface area of acrodont dentition in the chameleon.
Dosedělová, Hana; Štěpánková, Kateřina; Zikmund, Tomáš; Lesot, Herve; Kaiser, Jozef; Novotný, Karel; Štembírek, Jan; Knotek, Zdeněk; Zahradníček, Oldřich; Buchtová, Marcela
2016-09-01
Chameleon teeth develop as individual structures at a distance from the developing jaw bone during the pre-hatching period and also partially during the post-hatching period. However, in the adult, all teeth are fused together and tightly attached to the jaw bone by mineralized attachment tissue to form one functional unit. Tooth to bone as well as tooth to tooth attachments are so firm that if injury to the oral cavity occurs, several neighbouring teeth and pieces of jaw can be broken off. We analysed age-related changes in chameleon acrodont dentition, where ankylosis represents a physiological condition, whereas in mammals, ankylosis only occurs in a pathological context. The changes in hard-tissue morphology and mineral composition leading to this fusion were analysed. For this purpose, the lower jaws of chameleons were investigated using X-ray micro-computed tomography, laser-induced breakdown spectroscopy and microprobe analysis. For a long time, the dental pulp cavity remained connected with neighbouring teeth and also to the underlying bone marrow cavity. Then, a progressive filling of the dental pulp cavity by a mineralized matrix occurred, and a complex network of non-mineralized channels remained. The size of these unmineralized channels progressively decreased until they completely disappeared, and the dental pulp cavity was filled by a mineralized matrix over time. Moreover, the distribution of calcium, phosphorus and magnesium showed distinct patterns in the different regions of the tooth-bone interface, with a significant progression of mineralization in dentin as well as in the supporting bone. In conclusion, tooth-bone fusion in chameleons results from an enhanced production of mineralized tissue during post-hatching development. Uncovering the developmental processes underlying these outcomes and performing comparative studies is necessary to better understand physiological ankylosis; for that purpose, the chameleon can serve as a useful model species. © 2016 Anatomical Society.
Intensity-Modulated Radiotherapy for Sinonasal Tumors: Ghent University Hospital Update
DOE Office of Scientific and Technical Information (OSTI.GOV)
Madani, Indira; Bonte, Katrien; Vakaet, Luc
2009-02-01
Purpose: To report the long-term outcome of intensity-modulated radiotherapy (IMRT) for sinonasal tumors. Methods and Materials: Between July 1998 and November 2006, 84 patients with sinonasal tumors were treated with IMRT to a median dose of 70 Gy in 35 fractions. Of the 84 patients, 73 had a primary tumor and 11 had local recurrence. The tumor histologic type was adenocarcinoma in 54, squamous cell carcinoma in 17, esthesioneuroblastoma in 9, and adenoid cystic carcinoma in 4. The tumors were located in the ethmoid sinus in 47, maxillary sinus in 19, nasal cavity in 16, and multiple sites in 2.more » Postoperative IMRT was performed in 75 patients and 9 patients received primary IMRT. Results: The median follow-up of living patients was 40 months (range, 8-106). The 5-year local control, overall survival, disease-specific survival, disease-free survival, and freedom from distant metastasis rate was 70.7%, 58.5%, 67%, 59.3%, and 82.2%, respectively. No difference was found in local control and survival between patients with primary or recurrent tumors. On multivariate analysis, invasion of the cribriform plate was significantly associated with lower local control (p = 0.0001) and overall survival (p = 0.0001). Local and distant recurrence was detected in 19 and 10 patients, respectively. Radiation-induced blindness was not observed. One patient developed Grade 3 radiation-induced retinopathy and neovascular glaucoma. Nonocular late radiation-induced toxicity comprised complete lacrimal duct stenosis in 1 patient and brain necrosis in 3 patients. Osteoradionecrosis of the maxilla and brain necrosis were detected in 1 of the 5 reirradiated patients. Conclusion: IMRT for sinonasal tumors provides low rates of radiation-induced toxicity without blindness with high local control and survival. IMRT could be considered as the treatment of choi0008.« less
Outcomes and xerostomia after postoperative radiotherapy for oral and oropharyngeal carcinoma.
Wang, Zhong-He; Yan, Chao; Zhang, Zhi-Yuan; Zhang, Chen-Ping; Hu, Hai-Sheng; Tu, Wen-Yong; Kirwan, Jessica; Mendenhall, William M
2014-10-01
We compared outcomes and xerostomia grade after postoperative intensity-modulated radiation therapy (IMRT) and conventional radiotherapy (RT) in patients with oral and oropharyngeal carcinoma. Eighty-eight patients with oral cavity (n = 77) and oropharyngeal (n = 11) carcinoma underwent postoperative IMRT (n = 44) or conventional RT (n = 44). Outcomes, failure patterns, volume, doses, salivary gland V30, and xerostomia grade were evaluated. The median follow-up was 53 months (range, 48-58 months). The median interval from surgery to RT was 4 weeks (range, 3-6 weeks). Twenty-one patients (7 and 14 for the IMRT and conventional RT groups, respectively) experienced local-regional failure. For the IMRT group, all 7 local-regional failures occurred in the high-dose target volumes. For the conventional RT group, there were 12 in-field failures, 1 at the margin, and 1 out-of-field. Nine patients experienced distant failure (5 and 4 for the IMRT and conventional RT groups, respectively). The 4-year local-regional control, disease-free survival (DFS), overall survival (OS), and distant-metastasis rates for the IMRT and conventional RT groups were 84.1% versus 68.2% (p = .055), 68.2% versus 52.3% (p = .091), 70.5% versus 56.8% (p = .124), and 11.4% versus 9.1% (p = .927), respectively. Xerostomia grade after RT was lower for IMRT compared to conventional RT (p < .001). Postoperative IMRT for oral and oropharyngeal carcinoma significantly improves mean dose, salivary gland V30, and xerostomia grade when compared to conventional RT. The predominant failure pattern was local. No differences were found in survival outcomes between both groups. There was a marginal difference in local-regional control. © 2014 Wiley Periodicals, Inc.
Dynamical Signatures of Structural Connectivity Damage to a Model of the Brain Posed at Criticality.
Haimovici, Ariel; Balenzuela, Pablo; Tagliazucchi, Enzo
2016-12-01
Synchronization of brain activity fluctuations is believed to represent communication between spatially distant neural processes. These interareal functional interactions develop in the background of a complex network of axonal connections linking cortical and subcortical neurons, termed the human "structural connectome." Theoretical considerations and experimental evidence support the view that the human brain can be modeled as a system operating at a critical point between ordered (subcritical) and disordered (supercritical) phases. Here, we explore the hypothesis that pathologies resulting from brain injury of different etiologies are related to this model of a critical brain. For this purpose, we investigate how damage to the integrity of the structural connectome impacts on the signatures of critical dynamics. Adopting a hybrid modeling approach combining an empirical weighted network of human structural connections with a conceptual model of critical dynamics, we show that lesions located at highly transited connections progressively displace the model toward the subcritical regime. The topological properties of the nodes and links are of less importance when considered independently of their weight in the network. We observe that damage to midline hubs such as the middle and posterior cingulate cortex is most crucial for the disruption of criticality in the model. However, a similar effect can be achieved by targeting less transited nodes and links whose connection weights add up to an equivalent amount. This implies that brain pathology does not necessarily arise due to insult targeted at well-connected areas and that intersubject variability could obscure lesions located at nonhub regions. Finally, we discuss the predictions of our model in the context of clinical studies of traumatic brain injury and neurodegenerative disorders.
Liu, Yi; Du, Lian; Li, Yongmei; Liu, Haixia; Zhao, Wenjing; Liu, Dan; Zeng, Jinkun; Li, Xingbao; Fu, Yixiao; Qiu, Haitang; Li, Xirong; Qiu, Tian; Hu, Hua; Meng, Huaqing; Luo, Qinghua
2015-01-01
Abstract The mechanisms underlying the effects of electroconvulsive therapy (ECT) in major depressive disorder (MDD) are not fully understood. Resting-state functional magnetic resonance imaging (rs-fMRI) is a new tool to study the effects of brain stimulation interventions, particularly ECT. The authors aim to investigate the mechanisms of ECT in MDD by rs-fMRI. They used rs-fMRI to measure functional changes in the brain of first-episode, treatment-naive MDD patients (n = 23) immediately before and then following 8 ECT sessions (brief-pulse square-wave apparatus, bitemporal). They also computed voxel-wise amplitude of low-frequency fluctuation (ALFF) as a measure of regional brain activity and selected the left subgenual anterior cingulate cortex (sgACC) to evaluate functional connectivity between the sgACC and other brain regions. Increased regional brain activity measured by ALFF mainly in the left sgACC following ECT. Functional connectivity of the left sgACC increased in the ipsilateral parahippocampal gyrus, pregenual ACC, contralateral middle temporal pole, and orbitofrontal cortex. Importantly, reduction in depressive symptoms were negatively correlated with increased ALFF in the left sgACC and left hippocampus, and with distant functional connectivity between the left sgACC and contralateral middle temporal pole. That is, across subjects, as depression improved, regional brain activity in sgACC and its functional connectivity increased in the brain. Eight ECT sessions in MDD patients modulated activity in the sgACC and its networks. The antidepressant effects of ECT were negatively correlated with sgACC brain activity and connectivity. These findings suggest that sgACC-associated prefrontal-limbic structures are associated with the therapeutic effects of ECT in MDD. PMID:26559309
Polanía, Rafael; Paulus, Walter; Antal, Andrea; Nitsche, Michael A
2011-02-01
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that alters cortical excitability and activity in a polarity-dependent way. Stimulation for a few minutes has been shown to induce plastic alterations of cortical excitability and to improve cognitive performance. These effects might be related to stimulation-induced alterations of functional cortical network connectivity. We aimed to investigate the impact of tDCS on cortical network function by functional connectivity and graph theoretical analysis of the BOLD fMRI spontaneous activity. fMRI resting-state datasets were acquired immediately before and after 10-min bipolar tDCS during rest, with the anode placed over the left primary motor cortex (M1) and the cathode over the contralateral frontopolar cortex. For each dataset, grey matter voxel-based synchronization matrices were calculated and thresholded to construct undirected graphs. Nodal connectivity degree and minimum path length maps were calculated and compared before and after tDCS. Nodal minimum path lengths significantly increased in the left somatomotor (SM1) cortex after anodal tDCS, which means that the number of direct functional connections from the left SM1 to topologically distant grey matter voxels significantly decreased. In contrast, functional coupling between premotor and superior parietal areas with the left SM1 significantly increased. Additionally, the nodal connectivity degree in the left posterior cingulate cortex (PCC) area as well as in the right dorsolateral prefrontal cortex (right DLPFC) significantly increased. In summary, we provide initial support that tDCS-induced neuroplastic alterations might be related to functional connectivity changes in the human brain. Additionally, we propose our approach as a powerful method to track for neuroplastic changes in the human brain. Copyright © 2010 Elsevier Inc. All rights reserved.
Cold-Cap Temperature Profile Comparison between the Laboratory and Mathematical Model
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dixon, Derek R.; Schweiger, Michael J.; Riley, Brian J.
2015-06-01
The rate of waste vitrification in an electric melter is connected to the feed-to-glass conversion process, which occurs in the cold cap, a layer of reacting feed on top of molten glass. The cold cap consists of two layers: a low temperature (~100°C – ~800°C) region of unconnected feed and a high temperature (~800°C – ~1100°C) region of foam with gas bubbles and cavities mixed in the connected glass melt. A recently developed mathematical model describes the effect of the cold cap on glass production. For verification of the mathematical model, a laboratory-scale melter was used to produce a coldmore » cap that could be cross-sectioned and polished in order to determine the temperature profile related to position in the cold cap. The cold cap from the laboratory-scale melter exhibited an accumulation of feed ~400°C due to radiant heat from the molten glass creating dry feed conditions in the melter, which was not the case in the mathematical model where wet feed conditions were calculated. Through the temperature range from ~500°C – ~1100°C, there was good agreement between the model and the laboratory cold cap. Differences were observed between the two temperature profiles due to the temperature of the glass melts and the lack of secondary foam, large cavities, and shrinkage of the primary foam bubbles upon the cooling of the laboratory-scale cold cap.« less
Distant stereoacuity in children with anisometropic amblyopia.
Chung, Yeon Woong; Park, Shin Hae; Shin, Sun Young
2017-09-01
To characterize changes in distant stereoacuity using Frisby-Davis Distance test (FD2) and Distant Randot test (DR) during treatment for anisometropic amblyopia, to determine factors that influence posttreatment stereoacuity and to compare the two distant stereotests. Fifty-eight anisometropic amblyopic patients with an interocular difference of ≥1.00 diopter who achieved the visual acuity 20/20 following amblyopia treatment were retrospectively included. Stereoacuity using FD2 and DR for distant and Titmus test for near measurement were assessed and compared at the initial, intermediate, and final visit. Multivariate regression models were used to identify factors associated with initial and final stereoacuity. The two distant stereotests revealed a significant improvement in distant stereoacuity after successful amblyopia treatment. Distant stereoacuity using FD2 showed the greatest improvement during the follow up period. The number of nil scores was higher in DR than FD2 at each period. In multivariate analysis, better final stereoacuity was associated with better initial amblyopic eye acuity in both distant stereotests, but not in the Titmus test. Comparing the two distant stereotests, final stereoacuity using FD2 was associated with initial stereoacuity and was moderately related with the Titmus test at each period, but final stereoacuity using DR was not. Distant stereoacuity measured with both FD2 and DR showed significant improvement when the visual acuity of the amblyopic eye achieved 20/20. Changes in distant stereoacuity by FD2 and DR during the amblyopia treatment were somewhat different.
NASA Astrophysics Data System (ADS)
Stolzenburg, Maribeth; Marshall, Thomas C.; Karunarathne, Sumedhe; Orville, Richard E.
2018-10-01
Using video data recorded at 50,000 frames per second for nearby negative lightning flashes, estimates are derived for the length of positive upward connecting leaders (UCLs) that presumably formed prior to new ground attachments. Return strokes were 1.7 to 7.8 km distant, yielding image resolutions of 4.25 to 19.5 m. No UCLs are imaged in these data, indicating those features were too transient or too dim compared to other lightning processes that are imaged at these resolutions. Upper bound lengths for 17 presumed UCLs are determined from the height above flat ground or water of the successful stepped leader tip in the image immediately prior to (within 20 μs before) the return stroke. Better estimates of maximum UCL lengths are determined using the downward stepped leader tip's speed of advance and the estimated return stroke time within its first frame. For 17 strokes, the upper bound length of the possible UCL averages 31.6 m and ranges from 11.3 to 50.3 m. Among the close strokes (those with spatial resolution <8 m per pixel), the five which connected to water (salt water lagoon) have UCL upper bound estimates averaging significantly shorter (24.1 m) than the average for the three close strokes which connected to land (36.9 m). The better estimates of maximum UCL lengths for the eight close strokes average 20.2 m, with slightly shorter average of 18.3 m for the five that connected to water. All the better estimates of UCL maximum lengths are <38 m in this dataset
NASA Astrophysics Data System (ADS)
Guillet de Chatellus, H.; Lacot, E.; Glastre, W.; Jacquin, O.; Hugon, O.
2013-09-01
We provide a theoretical study of frequency-shifted feedback (FSF) lasers, i.e., lasers with an internal frequency shifter, seeded with a monochromatic wave. The resulting spectrum consists in a set of equidistant modes, labeled by n, whose phases vary quadratically with n. We prove the emergence of a temporal fractional Talbot effect, leading to generation of Fourier-transform-limited pulses at a repetition rate tunable by the parameters of the FSF cavity (cavity length and frequency shift per round trip), and limited by the spectral bandwidth of the laser. We characterize in detail the output field of this so-called “Talbot laser” and emphasize its specific intensity fluctuations. We evidence connections with some aspects of number theory by the appearance of Gauss sums and theta series in the expression of the laser field. Our predictions are in full agreement with the experimental results published in Guillet de Chatellus [Opt. ExpressOPEXFF1094-408710.1364/OE.21.015065 21, 15065 (2013)]. Practical applications and limitations are discussed.
NASA Astrophysics Data System (ADS)
Rendina, Ivo; Bellucci, Marco; Cocorullo, Giuseppe; Della Corte, Francesco G.; Iodice, Mario
2000-03-01
A new type of non-perturbing electromagnetic power sensor for microwaves and millimeter-waves, based on the thermo- optical effect in a silicon interferometric etalon cavity is presented. The incident field power is partially dissipated into the all-silicon metal-less etalon, constituting the sensing element of the detector, so causing its temperature increase. This, in turn, induces the intensity modulation of a probe laser beam reflected by the cavity after a multiple beam interference process. The sensing element is directly connected to an optical fiber for remote interrogation, so avoiding the use of perturbing coaxial cables. The performances of such a new class of non-perturbing and wideband probes, in terms of sensitivity and resolution are discussed in detail. The experimental results concerning the characterization of a preliminary prototype sensor are presented and compared with theoretical data. The dependence of the sensor response on the electromagnetic frequency and on the sensing element characteristics is finally discussed.
Wound Healing Problems in the Mouth
Politis, Constantinus; Schoenaers, Joseph; Jacobs, Reinhilde; Agbaje, Jimoh O.
2016-01-01
Wound healing is a primary survival mechanism that is largely taken for granted. The literature includes relatively little information about disturbed wound healing, and there is no acceptable classification describing wound healing process in the oral region. Wound healing comprises a sequence of complex biological processes. All tissues follow an essentially identical pattern to complete the healing process with minimal scar formation. The oral cavity is a remarkable environment in which wound healing occurs in warm oral fluid containing millions of microorganisms. The present review provides a basic overview of the wound healing process and with a discussion of the local and general factors that play roles in achieving efficient would healing. Results of oral cavity wound healing can vary from a clinically healed wound without scar formation and with histologically normal connective tissue under epithelial cells to extreme forms of trismus caused by fibrosis. Many local and general factors affect oral wound healing, and an improved understanding of these factors will help to address issues that lead to poor oral wound healing. PMID:27853435
Anode shroud for off-gas capture and removal from electrolytic oxide reduction system
Bailey, James L.; Barnes, Laurel A.; Wiedmeyer, Stanley G.; Williamson, Mark A.; Willit, James L.
2014-07-08
An electrolytic oxide reduction system according to a non-limiting embodiment of the present invention may include a plurality of anode assemblies and an anode shroud for each of the anode assemblies. The anode shroud may be used to dilute, cool, and/or remove off-gas from the electrolytic oxide reduction system. The anode shroud may include a body portion having a tapered upper section that includes an apex. The body portion may have an inner wall that defines an off-gas collection cavity. A chimney structure may extend from the apex of the upper section and be connected to the off-gas collection cavity of the body portion. The chimney structure may include an inner tube within an outer tube. Accordingly, a sweep gas/cooling gas may be supplied down the annular space between the inner and outer tubes, while the off-gas may be removed through an exit path defined by the inner tube.
New LaMAsH(x) (M = Co, Ni, or Cu) arsenides with covalent M-H chains.
Mizoguchi, Hiroshi; Park, SangWon; Hiraka, Haruhiro; Ikeda, Kazutaka; Otomo, Toshiya; Hosono, Hideo
2014-12-17
A new series of tetragonal LaPtSi-type mixed-anion arsenides, LaMAsH(x) (M = Co, Ni, or Cu), has been synthesized using high-temperature and high-pressure techniques. The crystal structure of these intermetallic compounds determined via powder neutron diffraction is composed of a 3D framework of three connected planes with the La ions filling the cavities in the structure. Each late transition-metal ion M, all of which have relatively large electronegativities, behaves like a main group element and forms a planar coordination configuration with three As ions. The trigonal-bipyramidal coordination adopted by the H in the cavity, HM2La3, is compressed along the C3 axis, and unusual M-H chains run along the x and y directions, reinforcing the covalent framework. These chains, which are unique in solids, are stabilized by covalent interactions between the M 4s and H 1s orbitals.
Hong, Jongwoo; Kim, Sun-Je; Kim, Inki; Yun, Hansik; Mun, Sang-Eun; Rho, Junsuk; Lee, Byoungho
2018-05-14
It has been hard to achieve simultaneous plasmonic enhancement of nanoscale light-matter interactions in terms of both electric and magnetic manners with easily reproducible fabrication method and systematic theoretical design rule. In this paper, a novel concept of a flat nanofocusing device is proposed for simultaneously squeezing both electric and magnetic fields in deep-subwavelength volume (~λ 3 /538) in a large area. Based on the funneled unit cell structures and surface plasmon-assisted coherent interactions between them, the array of rectangular nanocavity connected to a tapered nanoantenna, plasmonic metasurface cavity, is constructed by periodic arrangement of the unit cell. The average enhancement factors of electric and magnetic field intensities reach about 60 and 22 in nanocavities, respectively. The proposed outstanding performance of the device is verified numerically and experimentally. We expect that this work would expand methodologies involving optical near-field manipulations in large areas and related potential applications including nanophotonic sensors, nonlinear responses, and quantum interactions.
Needle lost in minimally invasive surgery: management proposal and literature review.
Medina, Luis G; Martin, Oscar; Cacciamani, Giovannni E; Ahmadi, Nariman; Castro, Juan C; Sotelo, Rene
2018-03-19
The reported incidence of intraoperative retained instruments, such as needles, hangs around 0.06-0.11%. Leaving a needle inside the abdominal cavity can have significant medical and legal consequences. In addition, the retrieval can be hampered due to the limited visualization of the scope during minimally invasive surgery. Factors associated with an increased probability for NL have been described. Prevention for this situation includes: having one needle at a time inside the cavity, effective communication between all personnel in the operating room, evaluation of the strength of the suture-needle connection, avoid parking of needles intraoperatively, and a proper needle withdrawal. Notwithstanding, no agreement has been made regarding NL management. Herein, we present a literature review, and a management proposal in which through a series of systematic steps, the surgical team can efficiently locate and retrieve a lost needle such as: examination of the surgical field, trocar visualization, trocar disassembly, and revision of the suction device. Finally, intraoperative or postoperative imaging can be utilized.
A simulation exercise of a cavity-type solar receiver using the HEAP program
NASA Technical Reports Server (NTRS)
Lansing, F. L.
1979-01-01
A computer program has been developed at JPL to support the advanced studies of solar receivers in high concentration solar-thermal-electric power plants. This work presents briefly the program methodology, input data required, expected output results, capabilities and limitations. The program was used to simulate an existing 5 kwt experimental receiver of a cavity type. The receiver is located at the focus of a paraboloid dish and is connected to a Stirling engine. Both steady state and transient performance simulation were given. Details about the receiver modeling were also presented to illustrate the procedure followed. Simulated temperature patterns were found in good agreement with test data obtained by high temperature thermocouples. The simulated receiver performance was extrapolated to various operating conditions not attained experimentally. The results of the parameterization study were fitted to a general performance expression to determine the receiver characteristic constraints. The latter were used to optimize the receiver operating conditions to obtain the highest overall conversion efficiency.
Goldstone and Higgs modes of photons inside a cavity
NASA Astrophysics Data System (ADS)
Yi-Xiang, Yu; Ye, Jinwu; Liu, Wu-Ming
2013-12-01
Goldstone and Higgs modes have been detected in various condensed matter, cold atom and particle physics experiments. Here, we demonstrate that the two modes can also be observed in optical systems with only a few (artificial) atoms inside a cavity. We establish this connection by studying the U(1)/Z2 Dicke model where N qubits (atoms) coupled to a single photon mode. We determine the Goldstone and Higgs modes inside the super-radiant phase and their corresponding spectral weights by performing both 1/J = 2/N expansion and exact diagonalization (ED) study at a finite N. We find nearly perfect agreements between the results achieved by the two approaches when N gets down even to N = 2. The quantum finite size effects at a few qubits make the two modes quite robust against an effectively small counterrotating wave term. We present a few schemes to reduce the critical coupling strength, so the two modes can be observed in several current available experimental systems by just conventional optical measurements.
Damaraju, E; Allen, E A; Belger, A; Ford, J M; McEwen, S; Mathalon, D H; Mueller, B A; Pearlson, G D; Potkin, S G; Preda, A; Turner, J A; Vaidya, J G; van Erp, T G; Calhoun, V D
2014-01-01
Schizophrenia is a psychotic disorder characterized by functional dysconnectivity or abnormal integration between distant brain regions. Recent functional imaging studies have implicated large-scale thalamo-cortical connectivity as being disrupted in patients. However, observed connectivity differences in schizophrenia have been inconsistent between studies, with reports of hyperconnectivity and hypoconnectivity between the same brain regions. Using resting state eyes-closed functional imaging and independent component analysis on a multi-site data that included 151 schizophrenia patients and 163 age- and gender matched healthy controls, we decomposed the functional brain data into 100 components and identified 47 as functionally relevant intrinsic connectivity networks. We subsequently evaluated group differences in functional network connectivity, both in a static sense, computed as the pairwise Pearson correlations between the full network time courses (5.4 minutes in length), and a dynamic sense, computed using sliding windows (44 s in length) and k-means clustering to characterize five discrete functional connectivity states. Static connectivity analysis revealed that compared to healthy controls, patients show significantly stronger connectivity, i.e., hyperconnectivity, between the thalamus and sensory networks (auditory, motor and visual), as well as reduced connectivity (hypoconnectivity) between sensory networks from all modalities. Dynamic analysis suggests that (1), on average, schizophrenia patients spend much less time than healthy controls in states typified by strong, large-scale connectivity, and (2), that abnormal connectivity patterns are more pronounced during these connectivity states. In particular, states exhibiting cortical-subcortical antagonism (anti-correlations) and strong positive connectivity between sensory networks are those that show the group differences of thalamic hyperconnectivity and sensory hypoconnectivity. Group differences are weak or absent during other connectivity states. Dynamic analysis also revealed hypoconnectivity between the putamen and sensory networks during the same states of thalamic hyperconnectivity; notably, this finding cannot be observed in the static connectivity analysis. Finally, in post-hoc analyses we observed that the relationships between sub-cortical low frequency power and connectivity with sensory networks is altered in patients, suggesting different functional interactions between sub-cortical nuclei and sensorimotor cortex during specific connectivity states. While important differences between patients with schizophrenia and healthy controls have been identified, one should interpret the results with caution given the history of medication in patients. Taken together, our results support and expand current knowledge regarding dysconnectivity in schizophrenia, and strongly advocate the use of dynamic analyses to better account for and understand functional connectivity differences.
Damaraju, E.; Allen, E.A.; Belger, A.; Ford, J.M.; McEwen, S.; Mathalon, D.H.; Mueller, B.A.; Pearlson, G.D.; Potkin, S.G.; Preda, A.; Turner, J.A.; Vaidya, J.G.; van Erp, T.G.; Calhoun, V.D.
2014-01-01
Schizophrenia is a psychotic disorder characterized by functional dysconnectivity or abnormal integration between distant brain regions. Recent functional imaging studies have implicated large-scale thalamo-cortical connectivity as being disrupted in patients. However, observed connectivity differences in schizophrenia have been inconsistent between studies, with reports of hyperconnectivity and hypoconnectivity between the same brain regions. Using resting state eyes-closed functional imaging and independent component analysis on a multi-site data that included 151 schizophrenia patients and 163 age- and gender matched healthy controls, we decomposed the functional brain data into 100 components and identified 47 as functionally relevant intrinsic connectivity networks. We subsequently evaluated group differences in functional network connectivity, both in a static sense, computed as the pairwise Pearson correlations between the full network time courses (5.4 minutes in length), and a dynamic sense, computed using sliding windows (44 s in length) and k-means clustering to characterize five discrete functional connectivity states. Static connectivity analysis revealed that compared to healthy controls, patients show significantly stronger connectivity, i.e., hyperconnectivity, between the thalamus and sensory networks (auditory, motor and visual), as well as reduced connectivity (hypoconnectivity) between sensory networks from all modalities. Dynamic analysis suggests that (1), on average, schizophrenia patients spend much less time than healthy controls in states typified by strong, large-scale connectivity, and (2), that abnormal connectivity patterns are more pronounced during these connectivity states. In particular, states exhibiting cortical–subcortical antagonism (anti-correlations) and strong positive connectivity between sensory networks are those that show the group differences of thalamic hyperconnectivity and sensory hypoconnectivity. Group differences are weak or absent during other connectivity states. Dynamic analysis also revealed hypoconnectivity between the putamen and sensory networks during the same states of thalamic hyperconnectivity; notably, this finding cannot be observed in the static connectivity analysis. Finally, in post-hoc analyses we observed that the relationships between sub-cortical low frequency power and connectivity with sensory networks is altered in patients, suggesting different functional interactions between sub-cortical nuclei and sensorimotor cortex during specific connectivity states. While important differences between patients with schizophrenia and healthy controls have been identified, one should interpret the results with caution given the history of medication in patients. Taken together, our results support and expand current knowledge regarding dysconnectivity in schizophrenia, and strongly advocate the use of dynamic analyses to better account for and understand functional connectivity differences. PMID:25161896
Core Stage Forward Skirt Umbilical Installation onto Mobile Laun
2017-05-25
Construction workers assist as a crane lifts the Core Stage Forward Skirt Umbilical up for installation on the mobile launcher tower at NASA's Kennedy Space Center in Florida. The mobile launcher tower will be equipped with a number of lines, called umbilicals that will connect to the Space Launch System (SLS) rocket and Orion spacecraft for Exploration Mission-1 (EM-1). The CSFSU will be located at about the 180-foot level on the tower, above the liquid oxygen tank. The CSFSU is an umbilical that will swing into position to provide connections to the core stage forward skirt of the SLS rocket, and then swing away before launch. Its main purpose is to provide conditioned air/GN2 to the SLS core stage forward skirt cavity. The Ground Systems Development and Operations Program is overseeing installation of the umbilicals.
Core Stage Forward Skirt Umbilical Installation onto Mobile Laun
2017-05-25
Cranes and rigging are being used to lift up the Core Stage Forward Skirt Umbilical (CSFSU) for installation on the mobile launcher tower at NASA's Kennedy Space Center in Florida. The mobile launcher tower will be equipped with a number of lines, called umbilicals that will connect to the Space Launch System (SLS) rocket and Orion spacecraft for Exploration Mission-1 (EM-1). The CSFSU will be located at about the 180-foot level on the tower, above the liquid oxygen tank. The CSFSU is an umbilical that will swing into position to provide connections to the core stage forward skirt of the SLS rocket, and then swing away before launch. Its main purpose is to provide conditioned air/GN2 to the SLS core stage forward skirt cavity. The Ground Systems Development and Operations Program is overseeing installation of the umbilicals.
Core Stage Forward Skirt Umbilical Installation onto Mobile Laun
2017-05-25
A construction worker welds a metal part during installation of the Core Stage Forward Skirt Umbilical on the mobile launcher tower at NASA's Kennedy Space Center in Florida. The mobile launcher tower will be equipped with a number of lines, called umbilicals that will connect to the Space Launch System (SLS) rocket and Orion spacecraft for Exploration Mission-1 (EM-1). The CSFSU will be located at about the 180-foot level on the tower, above the liquid oxygen tank. The CSFSU is an umbilical that will swing into position to provide connections to the core stage forward skirt of the SLS rocket, and then swing away before launch. Its main purpose is to provide conditioned air/GN2 to the SLS core stage forward skirt cavity. The Ground Systems Development and Operations Program is overseeing installation of the umbilicals.