Ground-state phase diagram in the Kugel-Khomskii model with finite spin-orbit interactions
NASA Astrophysics Data System (ADS)
Koga, Akihisa; Nakauchi, Shiryu; Nasu, Joji
2018-05-01
We study ground-state properties in the Kugel-Khomskii model on the two-dimensional honeycomb lattice. Using the cluster mean-field approximations, we deal with the exchange and spin-orbit couplings on an equal footing. We then discuss the stability of the ferromagnetically ordered states against the nonmagnetic state, which is adiabatically connected to the quantum spin liquid state realized in a strong spin-orbit coupling limit.
Lessons and challenges during a 5-year follow-up of 21 Composix Kugel implantations.
Wiegering, A; Schlegel, N; Isbert, C; Jurowich, C; Doht, S; Germer, C T; Dietz, U A
2013-08-01
From its introduction in 2000 until its US recall in December 2005, the Composix Kugel mesh was implanted in an estimated 350,000 patients worldwide. In our patients, minor postoperative complications were followed after a few years by more serious problems (persistent abdominal pain, infections, intestinal perforations). In this study, we take stock after a 5-year follow-up and issue a plea for improved product development strategies and the creation of hernia registries. Between 2003 and 2006, we implanted the Bard(®) Composix(®) Kugel(®) mesh in 21 patients (11 men, 10 women, mean age 63.2 ± 13.7 years) with incisional hernias using the open intraperitoneal onlay mesh technique. The mesh is made on one side of ePTFE and on the other of polypropylene and is expanded by a polyethylene (PET) memory recoil ring. The average follow-up was 45.5 months. All patients had at least one risk factor for hernia recurrence. Explanted prostheses were analyzed by scanning electron microscopy (SEM) and subjected to mechanical strength tests. During the postoperative course, six patients suffered a wound healing disorder. Ten patients complained of persistent abdominal wall pain and four experienced recurrence of the hernia. In one patient, the mesh had to be explanted due to chronic infection. In one patient, the PET memory recoil ring broke after 5 years of follow-up with consequent small bowel perforation. The PET memory recoil ring exhibited clear signs of degradation on SEM and unmistakable signs of material fatigue in a materials testing machine. Patients with recalled Composix Kugel meshes face a singular risk for complications that may occur even many years after implantation. The most serious complication is the breakage of its PET memory recoil ring. Since the recall of the Composix Kugel Mesh, we have discontinued its use. It is necessary that future complications are documented in a common post-market surveillance registry. Algorithms need to be developed and promoted to support affected patients and surgeons.
Role of spin-orbit coupling in the Kugel-Khomskii model on the honeycomb lattice
NASA Astrophysics Data System (ADS)
Koga, Akihisa; Nakauchi, Shiryu; Nasu, Joji
2018-03-01
We study the effective spin-orbital model for honeycomb-layered transition metal compounds, applying the second-order perturbation theory to the three-orbital Hubbard model with the anisotropic hoppings. This model is reduced to the Kitaev model in the strong spin-orbit coupling limit. Combining the cluster mean-field approximations with the exact diagonalization, we treat the Kugel-Khomskii type superexchange interaction and spin-orbit coupling on an equal footing to discuss ground-state properties. We find that a zigzag ordered state is realized in the model within nearest-neighbor interactions. We clarify how the ordered state competes with the nonmagnetic state, which is adiabatically connected to the quantum spin liquid state realized in a strong spin-orbit coupling limit. Thermodynamic properties are also addressed. The present paper should provide another route to account for the Kitaev-based magnetic properties in candidate materials.
conduction and radiation. The sphere is assumed to be sufficiently small so that Reynolds number, Peclet number and Bouguer number are much smaller than one. The results are obtained by an asymptotic expansion.
2003-08-01
Gerhard Braun, Dr. Rudolf Edse, Dr. Wolfgang Noeggerath, Hans Rister, and Dr. Theodor Zobel. (Dr. von Braun and the four other rocket specialists...Heinrich Albers, Herman Bottenhorn, Gerhard Krause , Dr. Ernst Kugel, and Hermann Nehlsen to Loewy Hydropress, Inc., in New York, while Dr. Claus...March 1948, Air Materiel Command maintained the Watson- and Cambridge-assigned German scientists at status quo, but added Dr. Wolfgang Pfister the next
Liu, Yaolin; Peng, Jinjin; Jiao, Limin; Liu, Yanfang
2016-01-01
Optimizing land-use allocation is important to regional sustainable development, as it promotes the social equality of public services, increases the economic benefits of land-use activities, and reduces the ecological risk of land-use planning. Most land-use optimization models allocate land-use using cell-level operations that fragment land-use patches. These models do not cooperate well with land-use planning knowledge, leading to irrational land-use patterns. This study focuses on building a heuristic land-use allocation model (PSOLA) using particle swarm optimization. The model allocates land-use with patch-level operations to avoid fragmentation. The patch-level operations include a patch-edge operator, a patch-size operator, and a patch-compactness operator that constrain the size and shape of land-use patches. The model is also integrated with knowledge-informed rules to provide auxiliary knowledge of land-use planning during optimization. The knowledge-informed rules consist of suitability, accessibility, land use policy, and stakeholders' preference. To validate the PSOLA model, a case study was performed in Gaoqiao Town in Zhejiang Province, China. The results demonstrate that the PSOLA model outperforms a basic PSO (Particle Swarm Optimization) in the terms of the social, economic, ecological, and overall benefits by 3.60%, 7.10%, 1.53% and 4.06%, respectively, which confirms the effectiveness of our improvements. Furthermore, the model has an open architecture, enabling its extension as a generic tool to support decision making in land-use planning.
Liu, Yaolin; Peng, Jinjin; Jiao, Limin; Liu, Yanfang
2016-01-01
Optimizing land-use allocation is important to regional sustainable development, as it promotes the social equality of public services, increases the economic benefits of land-use activities, and reduces the ecological risk of land-use planning. Most land-use optimization models allocate land-use using cell-level operations that fragment land-use patches. These models do not cooperate well with land-use planning knowledge, leading to irrational land-use patterns. This study focuses on building a heuristic land-use allocation model (PSOLA) using particle swarm optimization. The model allocates land-use with patch-level operations to avoid fragmentation. The patch-level operations include a patch-edge operator, a patch-size operator, and a patch-compactness operator that constrain the size and shape of land-use patches. The model is also integrated with knowledge-informed rules to provide auxiliary knowledge of land-use planning during optimization. The knowledge-informed rules consist of suitability, accessibility, land use policy, and stakeholders’ preference. To validate the PSOLA model, a case study was performed in Gaoqiao Town in Zhejiang Province, China. The results demonstrate that the PSOLA model outperforms a basic PSO (Particle Swarm Optimization) in the terms of the social, economic, ecological, and overall benefits by 3.60%, 7.10%, 1.53% and 4.06%, respectively, which confirms the effectiveness of our improvements. Furthermore, the model has an open architecture, enabling its extension as a generic tool to support decision making in land-use planning. PMID:27322619
Single-layer dual frequency patch antenna
NASA Astrophysics Data System (ADS)
Maci, S.; Gentili, G. B.; Avitabile, G.
1993-08-01
A configuration for a slotted patch antenna is introduced which allows two separate operating frequencies. Both of these frequencies are associated with a radiating mode almost identical to that of a standard patch. The two resonances are related to the patch width and the slot/patch length, respectively.
Allder, M A; Guilbeau, E J; Brandon, T A; Walker, A S; Koeneman, J B; Fisk, R L
1990-01-01
Patients undergoing repeat cardiac operations are higher operative risks than those undergoing an initial cardiac procedure because adhesion formation can occur if the native pericardium is not closed. A unique composite patch that may be used to augment the pericardial tissue when primary closure is not possible has been developed. The patch is made of a hydrogel, poly (2-hydroxyethyl methacrylate), reinforced with an ethylene tetrafluoroethylene (ETFE) mesh. The mesh provides the needed mechanical properties, whereas the patch's surface properties are comparable to the hydrogel. Two types of patches were fabricated: one with the mesh weave at a perpendicular orientation and one at 45 degrees to the principle loading direction. The patches were mechanically tested and compared with canine pericardium. Ultimate tensile strength of the patches is not significantly different from canine pericardium (p less than 0.05), are the patch suture strength is nearly twice that of canine pericardium. The perpendicular patch is stiffer than canine pericardium, whereas the 45 degree patch is not (p less than 0.05). The 45 degree patch shows considerable promise as a pericardial substitute because it closely matches the properties native canine pericardium.
Enhancement of Edge Stability with Lithium Wall Coatings in NSTX
NASA Astrophysics Data System (ADS)
Maingi, R.; Bell, R. E.; Leblanc, B. P.; Kaita, R.; Kaye, S. M.; Kugel, H. W.; Mansfield, D. K.; Osborne, T. H.
2008-11-01
ELM reduction or elimination while maintaining high confinement is essential for ITER, which has been designed for H-mode operation. Large ELMs are thought to be triggered by exceeding either edge current density and/or pressure gradient limits (peeling, ballooning modes). Stability calculations show that spherical tori should have access to higher pressure gradients and pedestal heights than higher R/a tokamaks, owing to access to second stability regimes[...1]. An ELM-free regime was recently observed in the NSTX following the application of lithium onto the graphite plasma facing components[......2]. ELMs were eliminated in phases[.....3], with the resulting pressure gradients and pedestal widths increasing substantially. Calculations with TRANSP have shown that the edge bootstrap current increased substantially, consistent with second stability access. These ELM-free discharges have a substantial improvement in energy confinement, up to the global βN˜ 5.5 limit. * Supported by US DOE DE-FG02-04ER54520, DE-AC-76CH03073, and DE-FC02-04ER54698. [.1] P. B. Snyder, et. al., Plasma Phys. Contr. Fusion 46 (2004) A131. [2] H. W. Kugel, et. al., Phys. Plasma 15 (2008) #056118. [3] D. M. Mansfield, et. al., J. Nucl. Materials (2009) submitted.
Maghsoudi, Hemmat; Ghaffari, Alireza
2011-01-01
Peptic ulcer perforations are a common emergency, but available literature is silent on the exact definition, incidence, management, and complications of peritonitis due to omental patch leakage. Retrospective data were collected on 422 patients who underwent omental patch repair of perforated peptic ulcer between March 20, 1999 and March 20, 2006. The definitive diagnosis of perforated peptic ulcer and omental patch leakage was obtained at surgery. Seventeen (4%) patients experienced generalized peritonitis due to omental patch leakage. Mean age was 60.6 years. Mortality rate was 29.4%, and the mean hospital stay was 23.6 days. Delay in surgical approach, shock on admission, and age were all significantly associated with increased mortality. Peritonitis due to omental patch leakage can result in significant morbidity and mortality. The most common causes of omental patch leakage and operative procedures were unknown and reinsertion of omentum, respectively. Factors such as shock on admission or delayed surgery, have significantly contributed to fatal outcomes and need careful attention.
Microstrip patch antenna receiving array operating in the Ku band
NASA Technical Reports Server (NTRS)
Walcher, Douglas A.
1996-01-01
Microstrip patch antennas were first investigated from the idea that it would be highly advantageous to fabricate radiating elements (antennas) on the same dielectric substrate as RF circuitry and transmission lines. Other advantages were soon discovered to be its lightweight, low profile, conformability to shaped surfaces, and low manufacturing costs. Unfortunately, these same patches continually exhibit narrow bandwidths, wide beamwidths, and low antenna gain. This thesis will present the design and experimental results of a microstrip patch antenna receiving array operating in the Ku band. An antenna array will be designed in an attempt to improve its performance over a single patch. Most Ku band information signals are either wide band television images or narrow band data and voice channels. An attempt to improve the gain of the array by introducing parasitic patches on top of the array will also be presented in this thesis.
Singlet Orbital Ordering in Bilayer Sr_{3}Cr_{2}O_{7}.
Jeanneau, Justin; Toulemonde, Pierre; Remenyi, Gyorgy; Sulpice, André; Colin, Claire; Nassif, Vivian; Suard, Emmanuelle; Salas Colera, Eduardo; Castro, Germán R; Gay, Frederic; Urdaniz, Corina; Weht, Ruben; Fevrier, Clement; Ralko, Arnaud; Lacroix, Claudine; Aligia, Armando A; Núñez-Regueiro, Manuel
2017-05-19
We perform an extensive study of Sr_{3}Cr_{2}O_{7}, the n=2 member of the Ruddlesden-Popper Sr_{n+1}Cr_{n}O_{3n+1} system. An antiferromagnetic ordering is clearly visible in the magnetization and the specific heat, which yields a huge transition entropy, Rln(6). By neutron diffraction as a function of temperature we have determined the antiferromagnetic structure that coincides with the one obtained from density functional theory calculations. It is accompanied by anomalous asymmetric distortions of the CrO_{6} octahedra. Strong coupling and Lanczos calculations on a derived Kugel-Khomskii Hamiltonian yield a simultaneous orbital and moment ordering. Our results favor an exotic ordered phase of orbital singlets not originated by frustration.
Computer-aided patch planning for treatment of complex coarctation of the aorta
NASA Astrophysics Data System (ADS)
Rietdorf, Urte; Riesenkampff, Eugénie; Kuehne, Titus; Huebler, Michael; Meinzer, Hans-Peter; Wolf, Ivo
2009-02-01
Between five and eight percent of all children born with congenitally malformed hearts suffer from coarctations of the aorta. Some severe coarctations can only be treated by surgical repair. Untreated, this defect can cause serious damage to organ development or even lead to death. Patch repair requires open surgery. It can affect patients of any age: newborns with severe coarctation and/or hypoplastic aortic arch as well as older patients with late diagnosis of coarctation of the aorta. Another patient group are patients of varying age with re-coarctation of the aorta or hypoplastic aortic arch after surgical and/or interventional repair. If anatomy is complex and interventional treatment by catheterization, balloon angioplasty or stent placement is not possible, surgery is indicated. The choice of type of surgery depends not only on the given anatomy but also on the experience the surgical team has with each method. One surgical approach is patch repair. A patch of a suitable shape and size is sewed into the aorta to expand the aortic lumen at the site of coarctation. At present, the shape and size of the patch are estimated intra-operatively by the surgeon. We have developed a software application that allows planning of the patch pre-operatively on the basis of magnetic resonance angiographic data. The application determines the diameter of the coarctation and/or hypoplastic segment and constructs a patch proposal by calculating the difference to the normal vessel diameter pre-operatively. Evaluation of MR angiographic datasets from 12 test patients with different kinds of aortic arch stenosis shows a divergence of only (1.5+/-1.2) mm in coarctation diameters between manual segmentations and our approach, with comparable time expenditure. Following this proposal the patch can be prepared and adapted to the patient's anatomy pre-operatively. Ideally, this leads to shorter operation times and a better long-term outcome with a reduced rate of residual stenosis and re-stenosis and aneurysm formation.
A Compact, Broadband Antenna for Planetary Surface-to-Surface Wireless Communications
NASA Technical Reports Server (NTRS)
Barr, Philip; Zaman, Afroz; Miranda, Felix
2006-01-01
The Compact Microstrip Monopole Antenna (CMMA) is a novel antenna design that combines a microstrip patch antenna with a three-dimensional structure to attain a highly directive, broadband, compact antenna. A Tri-Lobed Patch (TLP) was designed to minimize the patch's area while reducing the antenna's operating frequency. A Grounding Wall (GW) connects the patch to the ground plane and a Vertical Enclosure Wall (VEW) extends up away from portions of the patch's perimeter. This VEW supplies the antenna with a higher directivity in the radial direction as well as reduces the operating frequency. The CMMA was designed to operate at 2.23 GHz, but experimental results have shown this antenna resonates at 2.05 GHz which is on the order of approximately Lambda(sub o)/11.6 with respect to the antenna's largest dimension, with a directivity and bandwidth of 6.0 dBi, and 130 MHz (6.3 percent), respectively. This miniature, radially emitting antenna makes the CMMA attractive for planetary-based surface-to-surface communications.
Oracle Applications Patch Administration Tool (PAT) Beta Version
DOE Office of Scientific and Technical Information (OSTI.GOV)
2002-01-04
PAT is a Patch Administration Tool that provides analysis, tracking, and management of Oracle Application patches. This includes capabilities as outlined below: Patch Analysis & Management Tool Outline of capabilities: Administration Patch Data Maintenance -- track Oracle Application patches applied to what database instance & machine Patch Analysis capture text files (readme.txt and driver files) form comparison detail report comparison detail PL/SQL package comparison detail SQL scripts detail JSP module comparison detail Parse and load the current applptch.txt (10.7) or load patch data from Oracle Application database patch tables (11i) Display Analysis -- Compare patch to be applied with currentmore » Oracle Application installed Appl_top code versions Patch Detail Module comparison detail Analyze and display one Oracle Application module patch. Patch Management -- automatic queue and execution of patches Administration Parameter maintenance -- setting for directory structure of Oracle Application appl_top Validation data maintenance -- machine names and instances to patch Operation Patch Data Maintenance Schedule a patch (queue for later execution) Run a patch (queue for immediate execution) Review the patch logs Patch Management Reports« less
Maghsoudi, Hemmat; Ghaffari, Alireza
2011-01-01
Background/Aim: Peptic ulcer perforations are a common emergency, but available literature is silent on the exact definition, incidence, management, and complications of peritonitis due to omental patch leakage. Patients and Methods: Retrospective data were collected on 422 patients who underwent omental patch repair of perforated peptic ulcer between March 20, 1999 and March 20, 2006. The definitive diagnosis of perforated peptic ulcer and omental patch leakage was obtained at surgery. Results: Seventeen (4%) patients experienced generalized peritonitis due to omental patch leakage. Mean age was 60.6 years. Mortality rate was 29.4%, and the mean hospital stay was 23.6 days. Delay in surgical approach, shock on admission, and age were all significantly associated with increased mortality. Conclusions: Peritonitis due to omental patch leakage can result in significant morbidity and mortality. The most common causes of omental patch leakage and operative procedures were unknown and reinsertion of omentum, respectively. Factors such as shock on admission or delayed surgery, have significantly contributed to fatal outcomes and need careful attention. PMID:21372350
NASA Astrophysics Data System (ADS)
Ghosh, S. K.; Varshney, S. K.; Chakraborty, S.; Singh, L. L. K.; Chattopadhyay, S.
2018-03-01
Microstrip patch antenna of semicircular geometry has been investigated in view of miniaturization of conventional circular geometry. The precise operating frequency of the semicircular microstrip patch antenna is the most significant parameter to be determined in order to design such antenna system to achieve the optimum performance. In the present investigation an improved formulation is presented for accurate determination of the resonant frequency of semicircular patch. Also, the radiation property of such patch is thoroughly investigated. Through comparisons are documented amongst the circular and semicircular patches. It is revealed that, the semicircular patch offers more better radiation performance compared to circular.
Boolean Operations with Prism Algebraic Patches
Bajaj, Chandrajit; Paoluzzi, Alberto; Portuesi, Simone; Lei, Na; Zhao, Wenqi
2009-01-01
In this paper we discuss a symbolic-numeric algorithm for Boolean operations, closed in the algebra of curved polyhedra whose boundary is triangulated with algebraic patches (A-patches). This approach uses a linear polyhedron as a first approximation of both the arguments and the result. On each triangle of a boundary representation of such linear approximation, a piecewise cubic algebraic interpolant is built, using a C1-continuous prism algebraic patch (prism A-patch) that interpolates the three triangle vertices, with given normal vectors. The boundary representation only stores the vertices of the initial triangulation and their external vertex normals. In order to represent also flat and/or sharp local features, the corresponding normal-per-face and/or normal-per-edge may be also given, respectively. The topology is described by storing, for each curved triangle, the two triples of pointers to incident vertices and to adjacent triangles. For each triangle, a scaffolding prism is built, produced by its extreme vertices and normals, which provides a containment volume for the curved interpolating A-patch. When looking for the result of a regularized Boolean operation, the 0-set of a tri-variate polynomial within each such prism is generated, and intersected with the analogous 0-sets of the other curved polyhedron, when two prisms have non-empty intersection. The intersection curves of the boundaries are traced and used to decompose each boundary into the 3 standard classes of subpatches, denoted in, out and on. While tracing the intersection curves, the locally refined triangulation of intersecting patches is produced, and added to the boundary representation. PMID:21516262
A novel way to go whole-cell in patch-clamp experiments.
Inayat, Samsoon; Zhao, Yan; Cantrell, Donal R; Dikin, Dmitryi; Pinto, Lawrence H; Troy, John B
2010-11-01
With a conventional patch-clamp electrode, an Ag/AgCl wire sits stationary inside the pipette. To move from the gigaseal cell-attached configuration to whole-cell recording, suction is applied inside the pipette. We have designed and developed a novel Pushpen patch-clamp electrode, in which a W wire insulated and wound with Ag/AgCl wire can move linearly inside the pipette. The W wire has a conical tip, which can protrude from the pipette tip like a push pen, a procedure we call the Pushpen Operation. We use the Pushpen operation to impale the cell membrane in cell-attached configuration to go whole-cell without disruption of the gigaseal. We successfully recorded whole-cell currents from chinese hamster ovarian cells expressing influenza A virus protein A/M2, after obtaining whole-cell configuration with the Pushpen operation. This novel method of achieving whole-cell configuration may have a higher success rate than is the case with the conventional patch clamp technique.
Cell-Detection Technique for Automated Patch Clamping
NASA Technical Reports Server (NTRS)
McDowell, Mark; Gray, Elizabeth
2008-01-01
A unique and customizable machinevision and image-data-processing technique has been developed for use in automated identification of cells that are optimal for patch clamping. [Patch clamping (in which patch electrodes are pressed against cell membranes) is an electrophysiological technique widely applied for the study of ion channels, and of membrane proteins that regulate the flow of ions across the membranes. Patch clamping is used in many biological research fields such as neurobiology, pharmacology, and molecular biology.] While there exist several hardware techniques for automated patch clamping of cells, very few of those techniques incorporate machine vision for locating cells that are ideal subjects for patch clamping. In contrast, the present technique is embodied in a machine-vision algorithm that, in practical application, enables the user to identify good and bad cells for patch clamping in an image captured by a charge-coupled-device (CCD) camera attached to a microscope, within a processing time of one second. Hence, the present technique can save time, thereby increasing efficiency and reducing cost. The present technique involves the utilization of cell-feature metrics to accurately make decisions on the degree to which individual cells are "good" or "bad" candidates for patch clamping. These metrics include position coordinates (x,y) in the image plane, major-axis length, minor-axis length, area, elongation, roundness, smoothness, angle of orientation, and degree of inclusion in the field of view. The present technique does not require any special hardware beyond commercially available, off-the-shelf patch-clamping hardware: A standard patchclamping microscope system with an attached CCD camera, a personal computer with an imagedata- processing board, and some experience in utilizing imagedata- processing software are all that are needed. A cell image is first captured by the microscope CCD camera and image-data-processing board, then the image data are analyzed by software that implements the present machine-vision technique. This analysis results in the identification of cells that are "good" candidates for patch clamping (see figure). Once a "good" cell is identified, a patch clamp can be effected by an automated patchclamping apparatus or by a human operator. This technique has been shown to enable reliable identification of "good" and "bad" candidate cells for patch clamping. The ultimate goal in further development of this technique is to combine artificial-intelligence processing with instrumentation and controls in order to produce a complete "turnkey" automated patch-clamping system capable of accurately and reliably patch clamping cells with a minimum intervention by a human operator. Moreover, this technique can be adapted to virtually any cellular-analysis procedure that includes repetitive operation of microscope hardware by a human.
... patch from direct heat such as heating pads, electric blankets, heat lamps, saunas, hot tubs, and heated ... may make you drowsy. Do not drive a car or operate machinery until you know how this ...
Development of a Hard-Patch Approach for Scarf Repair of Composite Structure
2006-06-01
composite skins are bonded to a Ti- 6Al - 4V titanium alloy splice plate. The inboard and outboard ribs are also made of this alloy, as is the root rib which...operation. Options for the patch material include composite laminate, titanium alloy sheet laminate or solid titanium alloy. d) Semi-Hard Patch – The...patch is manufactured from a series of pre-cured composite laminates each containing several plies or titanium sheets, which are interleaved with
Is Decellularized Porcine Small Intestine Sub-mucosa Patch Suitable for Aortic Arch Repair?
Corno, Antonio F.; Smith, Paul; Bezuska, Laurynas; Mimic, Branko
2018-01-01
Introduction: We reviewed our experience with decellularized porcine small intestine sub-mucosa (DPSIS) patch, recently introduced for congenital heart defects. Materials and Methods: Between 10/2011 and 04/2016 a DPSIS patch was used in 51 patients, median age 1.1 months (5 days to 14.5 years), for aortic arch reconstruction (45/51 = 88.2%) or aortic coarctation repair (6/51 = 11.8%). All medical records were retrospectively reviewed, with primary endpoints interventional procedure (balloon dilatation) or surgery (DPSIS patch replacement) due to patch-related complications. Results: In a median follow-up time of 1.5 ± 1.1 years (0.6–2.3years) in 13/51 patients (25.5%) a re-intervention, percutaneous interventional procedure (5/51 = 9.8%) or re-operation (8/51 = 15.7%) was required because of obstruction in the correspondence of the DPSIS patch used to enlarge the aortic arch/isthmus, with median max velocity flow at Doppler interrogation of 4.0 ± 0.51 m/s. Two patients required surgery after failed interventional cardiology. The mean interval between DPSIS patch implantation and re-intervention (percutaneous procedure or re-operation) was 6 months (1–17 months). While there were 3 hospital deaths (3/51 = 5.9%) not related to the patch implantation, no early or late mortality occurred for the subsequent procedure required for DPSIS patch interventional cardiology or surgery. The median max velocity flow at Doppler interrogation through the aortic arch/isthmus for the patients who did not require interventional procedure or surgery was 1.7 ± 0.57 m/s. Conclusions: High incidence of re-interventions with DPSIS patch for aortic arch and/or coarctation forced us to use alternative materials (homografts and decellularized gluteraldehyde preserved bovine pericardial matrix). PMID:29900163
Multi-Band Miniaturized Patch Antennas for a Compact, Shielded Microwave Breast Imaging Array.
Aguilar, Suzette M; Al-Joumayly, Mudar A; Burfeindt, Matthew J; Behdad, Nader; Hagness, Susan C
2013-12-18
We present a comprehensive study of a class of multi-band miniaturized patch antennas designed for use in a 3D enclosed sensor array for microwave breast imaging. Miniaturization and multi-band operation are achieved by loading the antenna with non-radiating slots at strategic locations along the patch. This results in symmetric radiation patterns and similar radiation characteristics at all frequencies of operation. Prototypes were fabricated and tested in a biocompatible immersion medium. Excellent agreement was obtained between simulations and measurements. The trade-off between miniaturization and radiation efficiency within this class of patch antennas is explored via a numerical analysis of the effects of the location and number of slots, as well as the thickness and permittivity of the dielectric substrate, on the resonant frequencies and gain. Additionally, we compare 3D quantitative microwave breast imaging performance achieved with two different enclosed arrays of slot-loaded miniaturized patch antennas. Simulated array measurements were obtained for a 3D anatomically realistic numerical breast phantom. The reconstructed breast images generated from miniaturized patch array data suggest that, for the realistic noise power levels assumed in this study, the variations in gain observed across this class of multi-band patch antennas do not significantly impact the overall image quality. We conclude that these miniaturized antennas are promising candidates as compact array elements for shielded, multi-frequency microwave breast imaging systems.
Perforated gastric ulcer--reappraisal of surgical options.
Madiba, T E; Nair, R; Mulaudzi, T V; Thomson, S R
2005-08-01
The available operative procedures for perforated gastric ulcer are gastrectomy, ulcer excision and omental patch closure. This study analysed the outcome of these operative options in a single institution. Seventy-two patients (mean age 43 years, 62 males) with perforated gastric ulcers were managed by laparotomy. There were 34 lesser curve (incisural) and 38 antral ulcers. Partial gastrectomy was performed in 27 patients, ulcer excision in 27 and simple patch closure in 18. Two ulcers were malignant. The mortality rate was 18% (26% for gastrectomy, 19% for ulcer excision and 5% for patch closure). Shock on admission (p = 0.006) and Candida (p = 0.020) in the histological specimen were predictive of poor outcome. Hospital stay was similar in the 3 groups. Omental patch closure and ulcer excision are as effective as gastrectomy in the management of perforated gastric ulcer and merit consideration as first-line therapy in technically applicable cases.
Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios
NASA Technical Reports Server (NTRS)
Barbosa Kortright, Miguel A.; Waldstein, Seth W.; Simons, Rainee N.
2017-01-01
An almost square patch, a square patch and a stacked square patch with corner truncation for circular polarization (CP) are researched and developed at X-band for cognitive radios. Experimental results indicate, first, that the impedance bandwidth of a CP almost square patch fed from the edge by a 50 ohm line is 1.70 percent and second, that of a CP square patch fed from the ground plane side by a surface launch connector is 1.87 percent. Third, the impedance bandwidth of a CP stacked square patch fed by a surface launch connector is 2.22 percent. The measured center frequency for the CP square patch fed by a surface launch connector without and with an identical stacked patch is 8.45 and 8.1017 GHz, respectively. By stacking a patch, separated by a fixed air gap of 0.254 mm, the center frequency is observed to shift by as much as 348.3 MHz. The shift in the center frequency can be exploited to reconfigure the operating frequency by mechanically increasing the air gap. The results indicate that a tuning bandwidth of about 100 MHz can be achieved when the distance of separation between the driven patch and the stacked patch is increased from its initial setting of 0.254 to 1.016 mm.
Experimental Fatigue Study of Composite Patch Repaired Steel Plates with Cracks
NASA Astrophysics Data System (ADS)
Karatzas, Vasileios A.; Kotsidis, Elias A.; Tsouvalis, Nicholas G.
2015-10-01
Cracks are among the most commonly encountered defects in metallic structures operating at sea. Composite patch repairing is a repair method which is gaining popularity as it counters most of the problems faced by conventional renewal repairs. Extensive studies can be found in the literature addressing the efficiency of this novel repair method using techniques which meet higher performance and monitoring standards than these commonly found in naval applications. In this work the efficiency of practices widely used in the ship repair industry for the implementation of composite patch repairing is addressed. To this end, steel plates repaired with composite patches were tested under fatigue loading. The composite patches consisted of carbon fibers in epoxy matrix and were directly laminated to the steel surface using the vacuum infusion method. Two different surface preparation methods, namely grit-blasting and mechanical treatment with the use of a needle gun were studied. In addition, in order to account for the harsh environmental conditions during the operating life of the structure and to study its effect on the repair, two different aging scenarios were considered. Non-destructive evaluation of the patches was performed so as to assess the quality of the repair, and the evolution of debonding during testing.
NASA Astrophysics Data System (ADS)
Inamdar, Kirti; Kosta, Y. P.; Patnaik, S.
2014-10-01
In this paper, we present the design of a metamaterial-based microstrip patch antenna, optimized for bandwidth and multiple frequency operations. A criss-cross structure has been proposed, this shape has been inspired from the famous Jerusalem cross. The theory and design formulas to calculate various parameters of the proposed antenna have been presented. Design starts with the analysis of the proposed unit cell structure, and validating the response using software- HFSS Version 13, to obtain negative response of ε and μ- metamaterial. Following this, a metamaterial-based-microstrip-patch-antenna is designed. A detailed comparative study is conducted exploring the response of the designed patch made of metamaterial and that of the conventional patch. Finally, antenna parameters such as gain, bandwidth, radiation pattern, and multiple frequency responses are investigated and optimised for the same and present in table and response graphs. It is also observed that the physical dimension of the metamaterial-based patch antenna is smaller compared to its conventional counterpart operating at the same fundamental frequency. The challenging part was to develop metamaterial based on some signature structures and techniques that would offer advantage in terms of BW and multiple frequency operation, which is demonstrated in this paper. The unique shape proposed in this paper gives improvement in bandwidth without reducing the gain of the antenna.
Best practices for level-up patching operation.
DOT National Transportation Integrated Search
2012-12-01
Level-up patching is a common corrective maintenance activity in Texas performed by most districts. It involves laying down a thin asphalt mix layer over an existing pavement in areas of sagging or rutting to improve the ride score and reduce pavemen...
Orbital implant exposure treatment with porcine dermal collagen patching.
Alwitry, A; Burns, S J; Abercrombie, L C
2006-09-01
To present a small case series of orbital implant exposures treated with porcine dermal collagen (Permacol, Tissue Science Laboratories PLC, Aldershot, Hants, UK) patching. A retrospective chart review of three cases of orbital implant exposure treated with Permacol patching. Three cases were identified. There were 4 operative episodes of Permacol patching (one socket had two attempts at permacol patching). In all 4 cases the patch rapidly failed and melted away leaving behind the orbital implant exposure. All 3 patients required implant removal. Orbital implant exposure remains a major long-term complication of evisceration and enucleation procedures. On the basis of our experience, we would not recommend using Permacol as a non-autologous material for covering exposed Medpor (Medpor, Porex Surgical, Atlanta, Georgia, USA) orbital implants. Further study is required to fully assess the safety and efficacy profile of Permacol in socket surgery.
2012-01-01
Background While progress has been made to develop automatic segmentation techniques for mitochondria, there remains a need for more accurate and robust techniques to delineate mitochondria in serial blockface scanning electron microscopic data. Previously developed texture based methods are limited for solving this problem because texture alone is often not sufficient to identify mitochondria. This paper presents a new three-step method, the Cytoseg process, for automated segmentation of mitochondria contained in 3D electron microscopic volumes generated through serial block face scanning electron microscopic imaging. The method consists of three steps. The first is a random forest patch classification step operating directly on 2D image patches. The second step consists of contour-pair classification. At the final step, we introduce a method to automatically seed a level set operation with output from previous steps. Results We report accuracy of the Cytoseg process on three types of tissue and compare it to a previous method based on Radon-Like Features. At step 1, we show that the patch classifier identifies mitochondria texture but creates many false positive pixels. At step 2, our contour processing step produces contours and then filters them with a second classification step, helping to improve overall accuracy. We show that our final level set operation, which is automatically seeded with output from previous steps, helps to smooth the results. Overall, our results show that use of contour pair classification and level set operations improve segmentation accuracy beyond patch classification alone. We show that the Cytoseg process performs well compared to another modern technique based on Radon-Like Features. Conclusions We demonstrated that texture based methods for mitochondria segmentation can be enhanced with multiple steps that form an image processing pipeline. While we used a random-forest based patch classifier to recognize texture, it would be possible to replace this with other texture identifiers, and we plan to explore this in future work. PMID:22321695
Analysis of single band and dual band graphene based patch antenna for terahertz region
NASA Astrophysics Data System (ADS)
George, Jemima Nissiyah; Madhan, M. Ganesh
2017-10-01
A microstrip patch antenna is designed using a very thin layer of graphene as the radiating patch, which is fed by a microstrip transmission line. The graphene based patch is designed on a silicon substrate having a dielectric constant of 11.9, to radiate at a single frequency of 2.6 THz. Further, this antenna is made to resonate at dual frequencies of 2.48 THz and 3.35 THz, by changing the substrate height, which is reported for the first time. Various antenna parameters such as return loss, VSWR, gain, efficiency and bandwidth are also determined for the single and dual band operation. For the single band operation, a bandwidth of 145.4 GHz and an efficiency of 92% was achieved. For dual band operation, a maximum bandwidth of 140.5 GHz was obtained at 3.35 THz and an efficiency of 87.3% was obtained at the first resonant frequency of 2.48 THz. The absorption cross section of the antenna is also analysed for various substrate heights and has maximum peaks at the corresponding resonating frequencies. The simulation has been carried out by using a full wave electromagnetic simulator based on FDTD method.
HeatWurx patching at two locations in San Antonio.
DOT National Transportation Integrated Search
2012-06-01
Patching asphalt pavement is an important, necessary part of TxDOT operations. Cracked and failed areas : need to be replaced by high quality, sound pavement in order to meet the needs of the traveling public. This : report documents the placing, cos...
Transparent solar antenna of 28 GHz using transparent conductive oxides (TCO) thin film
NASA Astrophysics Data System (ADS)
Ali, N. I. Mohd; Misran, N.; Mansor, M. F.; Jamlos, M. F.
2017-05-01
This paper presents the analysis of 28GHz solar patch antenna using the variations of transparent conductive oxides (TCO) thin film as the radiating patch. Solar antenna is basically combining the function of antenna and solar cell into one device and helps to maximize the usage of surface area. The main problem of the existing solar antenna is the radiating patch which made of nontransparent material, such as copper, shadowing the solar cell and degrades the total solar efficiency. Hence, by using the transparent conductive oxides (TCO) thin film as the radiating patch, this problem can be tackled. The TCO thin film used is varied to ITO, FTO, AgHT-4, and AgHT-8 along with glass as substrate. The simulation of the antenna executed by using Computer Simulation Technology (CST) Microwave Studio software demonstrated at 28 GHz operating frequency for 5G band applications. The performance of the transparent antennas is compared with each other and also with the nontransparent patch antenna that using Rogers RT5880 as substrate, operating at the same resonance frequency and then, the material that gives the best performance is identified.
Development and evaluation of thermoplastic street maintenance material
NASA Technical Reports Server (NTRS)
Siemens, W. D.
1973-01-01
An all-weather permanent street patching material was investigated for flexible and rigid pavements. The economic, operational, and material requirements are discussed along with the results of field tests with various mixtures of EVA resins and asphalt. Cost analyses for thermoplastic patching methods are included.
A monolithic patch-clamping amplifier with capacitive feedback.
Prakash, J; Paulos, J J; Jensen, D N
1989-03-01
Patch-clamping is an established method for directly measuring ionic transport through cellular membranes with sufficient resolution to observe open/close transitions of individual channel molecules. This paper describes an alternative technique for patch-clamping which uses a capacitor as the transimpedance element. This approach eliminates bandwidth and saturation limitations experienced with resistive patch-clamping amplifiers. A complete monolithic design featuring an on-chip operational amplifier, a capacitor array with gain-ranging from 30 pF down to 0.03 pF, and reset and gain ranging switches has been fabricated using 5 microns CMOS technology. It is shown that the voltage noise of the CMOS operational amplifier limits the overall noise performance, but that performance competitive with conventional instruments can be achieved over a 10 kHz bandwidth, at least for small input capacitances (less than or equal to 5 pF). Results are presented along with an analysis and comparison of noise performance using both resistive and capacitive elements.
Manouguian, S; Abu-Aishah, N; Neitzel, J
1979-09-01
The experimental results of patch enlargement of the aortic and mitral valve rings with aortic and mitral double valve replacement are reported. The operative technique of this new surgical method is described and the indications are discussed.
Laparoscopic repair of perforated peptic ulcer: patch versus simple closure.
Abd Ellatif, M E; Salama, A F; Elezaby, A F; El-Kaffas, H F; Hassan, A; Magdy, A; Abdallah, E; El-Morsy, G
2013-01-01
Laparoscopic correction of perforated peptic ulcer (PPU) has become an accepted way of management. Patch omentoplasty stayed for decades the main method of repair. The goal of the present study was to evaluate whether laparoscopic simple repair of PPU is as safe as patch omentoplasty. Since June 2005, 179 consecutive patients of PPU were treated by laparoscopic repair at our centers. We conducted a retrospective chart review in December 2012. Group I (patch group) included patients who were treated with standard patch omentoplasty. Group II (non-patch group) included patients who received simple repair without patch. From June 2007 to Dec. 2012, 179 consecutive patients of PPU who were treated by laparoscopic repair at our centers were enrolled in this multi-center retrospective study. 108 patients belong to patch group. While 71 patients were treated with laparoscopic simple repair. Operative time was significantly shorter in group II (non patch) (p = 0.01). No patient was converted to laparotomy. There was no difference in age, gender, ASA score, surgical risk (Boey's) score, and incidence of co-morbidities. Both groups were comparable in terms of hospital stay, time to resume oral intake, postoperative complications and surgical outcomes. Laparoscopic simple repair of PPU is a safe procedure compared with the traditional patch omentoplasty in presence of certain selection criteria. Copyright © 2013 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Preparation of active 3D film patches via aligned fiber electrohydrodynamic (EHD) printing
NASA Astrophysics Data System (ADS)
Wang, Jun-Chuan; Zheng, Hongxia; Chang, Ming-Wei; Ahmad, Zeeshan; Li, Jing-Song
2017-03-01
The design, preparation and application of three-dimensional (3D) printed structures have gained appreciable interest in recent times, particularly for drug dosage development. In this study, the electrohydrodynamic (EHD) printing technique was developed to fabricate aligned-fiber antibiotic (tetracycline hydrochloride, TE-HCL) patches using polycaprolactone (PCL), polyvinyl pyrrolidone (PVP) and their composite system (PVP-PCL). Drug loaded 3D patches possessed perfectly aligned fibers giving rise to fibrous strut orientation, variable inter-strut pore size and controlled film width (via layering). The effect of operating parameters on fiber deposition and alignment were explored, and the impact of the film structure, composition and drug loading was evaluated. FTIR demonstrated successful TE-HCL encapsulation in aligned fibers. Patches prepared using PVP and TE-HCL displayed enhanced hydrophobicity. Tensile tests exhibited changes to mechanical properties arising from additive effects. Release of antibiotic from PCL-PVP dosage forms was shown over 5 days and was slower compared to pure PCL or PVP. The printed patch void size also influenced antibiotic release behavior. The EHDA printing technique provides an exciting opportunity to tailor dosage forms in a single-step with minimal excipients and operations. These developments are crucial to meet demands where dosage forms cannot be manufactured rapidly or when a personalized approach is required.
NASA Astrophysics Data System (ADS)
Lee, Jun Kyu; Seung, Hong Min; Park, Chung Il; Lee, Joo Kyung; Lim, Do Hyeong; Kim, Yoon Young
2018-02-01
Real-time uninterrupted measurement for torsional vibrations of rotating shafts is crucial for permanent health monitoring. So far, strain gauge systems with telemetry units have been used for real-time monitoring. However, they have a critical disadvantage in that shaft operations must be stopped intermittently to replace telemetry unit batteries. To find an alternative method to carry out battery-less real-time measurement for torsional vibrations of rotating shafts, a magnetostrictive patch sensor system was proposed in the present study. Since the proposed sensor does not use any powered telemetry system, no battery is needed and thus there is no need to stop rotating shafts for battery replacement. The proposed sensor consists of magnetostrictive patches and small magnets tightly bonded onto a shaft. A solenoid coil is placed around the shaft to convert magnetostrictive patch deformation by shaft torsional vibration into electric voltage output. For sensor design and characterization, investigations were performed in a laboratory on relatively small-sized stationary solid shaft. A magnetostrictive patch sensor system was then designed and installed on a large rotating propulsion shaft of an LPG carrier ship in operation. Vibration signals were measured using the proposed sensor system and compared to those measured with a telemetry unit-equipped strain gauge system.
Preparation of active 3D film patches via aligned fiber electrohydrodynamic (EHD) printing
Wang, Jun-Chuan; Zheng, Hongxia; Chang, Ming-Wei; Ahmad, Zeeshan; Li, Jing-Song
2017-01-01
The design, preparation and application of three-dimensional (3D) printed structures have gained appreciable interest in recent times, particularly for drug dosage development. In this study, the electrohydrodynamic (EHD) printing technique was developed to fabricate aligned-fiber antibiotic (tetracycline hydrochloride, TE-HCL) patches using polycaprolactone (PCL), polyvinyl pyrrolidone (PVP) and their composite system (PVP-PCL). Drug loaded 3D patches possessed perfectly aligned fibers giving rise to fibrous strut orientation, variable inter-strut pore size and controlled film width (via layering). The effect of operating parameters on fiber deposition and alignment were explored, and the impact of the film structure, composition and drug loading was evaluated. FTIR demonstrated successful TE-HCL encapsulation in aligned fibers. Patches prepared using PVP and TE-HCL displayed enhanced hydrophobicity. Tensile tests exhibited changes to mechanical properties arising from additive effects. Release of antibiotic from PCL-PVP dosage forms was shown over 5 days and was slower compared to pure PCL or PVP. The printed patch void size also influenced antibiotic release behavior. The EHDA printing technique provides an exciting opportunity to tailor dosage forms in a single-step with minimal excipients and operations. These developments are crucial to meet demands where dosage forms cannot be manufactured rapidly or when a personalized approach is required. PMID:28272513
Sabokrou, Mohammad; Fayyaz, Mohsen; Fathy, Mahmood; Klette, Reinhard
2017-02-17
This paper proposes a fast and reliable method for anomaly detection and localization in video data showing crowded scenes. Time-efficient anomaly localization is an ongoing challenge and subject of this paper. We propose a cubicpatch- based method, characterised by a cascade of classifiers, which makes use of an advanced feature-learning approach. Our cascade of classifiers has two main stages. First, a light but deep 3D auto-encoder is used for early identification of "many" normal cubic patches. This deep network operates on small cubic patches as being the first stage, before carefully resizing remaining candidates of interest, and evaluating those at the second stage using a more complex and deeper 3D convolutional neural network (CNN). We divide the deep autoencoder and the CNN into multiple sub-stages which operate as cascaded classifiers. Shallow layers of the cascaded deep networks (designed as Gaussian classifiers, acting as weak single-class classifiers) detect "simple" normal patches such as background patches, and more complex normal patches are detected at deeper layers. It is shown that the proposed novel technique (a cascade of two cascaded classifiers) performs comparable to current top-performing detection and localization methods on standard benchmarks, but outperforms those in general with respect to required computation time.
Grambow, E; Heller, T; Wieneke, P; Weiß, C; Klar, E; Weinrich, M
2018-01-01
Duplex ultrasound is the first choice in diagnostics and surveillance of stenoses of the internal carotid arteries before and even after surgery. Therefore, the quality of duplex ultrasound is crucial to investigate these vascular pathologies. Aim of this study was the evaluation whether different surgical techniques affect the postoperative quality of duplex ultrasound. In a time period from January to May 2015 duplex ultrasound of the cervical vessels was performed in 75 patients after unilateral endarterectomy of the internal carotid artery at our department between 2006 and 2012. Thereby, the non-operated contralateral side served as a control. Study groups were defined by the surgical techniques of eversion- or thrombendarterectomy with patch plasty using different patch materials and/or a haemostatic sealant. Duplex ultrasound analysis included acoustic impedance, extinction of ultrasound, thickness of skin and individual anatomic aspects of the patients. Carotid endarterectomy itself reduced intravascular grey levels, skin thickness and increased extinction of duplex ultrasound when compared to the non-operated side of the neck. In contrast, neither the kind of chosen operative technique nor the use of different patch materials or the application of a haemostatic sealant showed an effect in this regards. Whereas carotid endarterectomy per se worsens the quality of postoperative duplex ultrasound, the different analysed surgical techniques as well as used patches and the application of a haemostatic sealant can be assumed to be equal regarding the quality of postoperative ultrasound.
Superconducting antennas for telecommunication applications based on dual mode cross slotted patches
NASA Astrophysics Data System (ADS)
Cassinese, A.; Barra, M.; Fragalà, I.; Kusunoki, M.; Malandrino, G.; Nakagawa, T.; Perdicaro, L. M. S.; Sato, K.; Ohshima, S.; Vaglio, R.
2002-08-01
Dual mode devices based on high temperature superconducting films represent an interesting class for telecommunication applications since they combine a miniaturized size with a good power handling. Here we report on a novel compact antenna obtained by crossing a square patch with two or more slots. The proposed design has an antenna size reduction of about 40% as compared to the conventional square patch microstrip antennas. Single patch antenna both with linear (LP) and circular (CP) polarization operating in the X-band have been designed and tested at prototype level. They are realized by using double sided (YBa 2Cu 3O 7- x) YBCO and Tl 2Ba 2Ca 1Cu 2O 8 (Tl-2212) superconducting films grown on MgO substrates and tested with a portable cryocooler. They showed at T=77 K a return loss <25 dB and a power handling of 23 dBm. Exemplary 16 elements arrays LP antennas operating in the X band have been also realized by using YBCO film grown on 2 ″ diameter MgO substrate.
Spatial and temporal variation in sponge spicule patches at Station M, northeast Pacific.
Laguionie-Marchais, C; Kuhnz, L A; Huffard, C L; Ruhl, H A; Smith, K L
Changes in habitat-forming organisms can have complex consequences for associated species. Sessile epibenthic glass "plate" sponges (Porifera: Hexactinellida) are conspicuous inhabitants of soft-sediment abyssal areas and their siliceous spicules create persistent spicule patches on the seafloor. Sponge spicule patch density, spatial dispersion, and percent cover were examined over a seven-year period (2006-2013) using remotely operated vehicle videos from Station M in the abyssal northeast Pacific (50˚00N, 123˚00W, ~4,000 m depth). There was an apparent large increase in newly dead plate sponges in February 2007 compared with December 2006, with this trend continuing through June 2007 (mean 0.03 % cover increasing to 0.33 %). A second increase in mean percent cover of dead plate sponges occurred from May 2011 (0.24 %) through June 2012 (0.60 %). Among the 28 megafaunal taxa occurring in association with the patches, the distributions of three taxa [two sponge taxa (Porifera) and brittle stars (Ophiuroidea)] suggested selectivity for the sponge spicule patches. The community structure of visible megafauna within sponge spicule patches was different when compared with that outside the patches suggesting that the sponges, after death, provide preferred habitat patches for certain benthic megafauna. These findings indicate that sponge spicule patches contribute to habitat heterogeneity in space and time.
Wendling, Mark R; Linn, John G; Keplinger, Kara M; Mikami, Dean J; Perry, Kyle A; Melvin, W Scott; Needleman, Bradley J
2013-02-01
Marginal ulcer formation remains a significant complication of Roux-en-Y gastric bypass (RYGB). Up to 1 % of all RYGB patients will develop free perforation of a marginal ulcer. Classically, this complication has required anastomotic revision; however, this approach is associated with significant morbidity. Several small series have suggested that omental patch repair may be effective. The aim of this study was to examine the management of perforated marginal ulcers following RYGB. All patients who underwent operative intervention for perforated ulcers between 2003 and 2011 were reviewed. Those with a history of RYGB with perforation of a marginal ulcer were included in the analysis. Data collected included operative approach, operative time, blood loss, length of hospital stay, complications, smoking history, and steroid or NSAID use. From January 2003 to December 2011, a total of 1,760 patients underwent RYGB at our institution. Eighteen (0.85 %) developed perforation of a marginal ulcer. Three patients' original procedure was performed at another institution. Eight patients (44 %) had at least one risk factor for ulcer formation. Treatment included omental patch repair (laparoscopic, n = 7; open, n = 9) or anastomotic revision (n = 2). Compared to anastomotic revision, omental patch repair had shorter OR time (101 ± 57 vs. 138 ± 2 min), decreased estimated blood loss (70 ± 72 vs. 250 ± 71 mL), and shorter total length of stay (5.6 ± 1.4 vs. 11.0 ± 5.7 days). Perforated marginal ulcer represents a significant complication of RYGB. Patients should be educated to reduce risk factors for perforation, as prolonged proton pump inhibitor therapy may not prevent this complication in a patient with even just one risk factor. In our sample population we found laparoscopic or open omental patch repair to be a safe and effective treatment for this condition and it was associated with decreased operative time, blood loss, and length of stay.
Design And Simulation Of Microstrip Antenna Of 2.4 GHz Using CST
NASA Astrophysics Data System (ADS)
Thakur, O. P.; Kushwaha, Alok K.
2011-12-01
This article describes the design, fabrication and testing of micro strip patch antennas operating at 2.4 GHz. Consideration is given on practical design technique, including substrate selection and antenna measurements. It is emphasised to the radiation properties of the antennas—the radiation pattern and polarization purity. A micro strip patch antenna consists of a very thin metallic patch placed a small fraction of a wavelength above a conducting ground-plane. The patch and ground-plane are separated by a dielectric. The patch conductor is normally copper and can assume any shape, but simple geometries generally are used, and this simplifies the analysis and performance prediction. The patches are usually photo etched on the dielectric substrate. The substrate is usually non-magnetic. The relative permittivity of the substrate is normally in the region between 1 and 4, which enhances the fringing fields that account for radiation, but higher values may be used in special circumstances. Due to its simple geometry, the half wave rectangular patch is the most commonly used micro strip antenna. It is characterized by its length L, width w and thickness h. The simplest method of feeding the patch is by a coplanar micro strip line, also photo etched on the substrate. Coaxial feeds are also widely used.
Foreman,Behnken,and Linnehan place STS-123 patch on wall in the A/L during Joint Operations
2008-03-23
S123-E-008756 (23 March 2008) --- Astronauts Mike Foreman (left), Robert L. Behnken and Rick Linnehan, all STS-123 mission specialists, add the STS-123 patch to the growing collection of insignias representing crews who have performed spacewalks from the Quest Airlock of the International Space Station.
Methylphenidate Transdermal Patch
... of heat such as hair dryers, heating pads, electric blankets, and heated waterbeds.Be careful not to ... or operate dangerous machinery. Do not drive a car or operate machinery until you know how this ...
Riquelme M, Hugo; Wood V, David; Martínez F, Santiago; Carmona M, Fernando; Peña V, Axel; Wegner A, Adriana
2017-06-01
Noninvasive ventilation (NIV) frequently involves the development of facial pressure ulcers (FPU). Its prevention considers the empirical use of protective patches between skin and mask, in order to reduce the pressure exerted by it. To evaluate the effect of protective patches on the pressure exerted by the facial mask, and its impact on the programmed ventilatory parameters. Bilevel NIV simulated model using full face mask in phantom with a physiological airway (ALS PRO +) in supine position. Forehead, chin and cheekbones pressure were measured using 3 types of standard protective patches versus a control group using pressure sensors (Interlinks Electronics®). The values obtained with the protective patches-mask model were evaluated in the programmed variables maximum inspiratory flow (MIF)), expired tidal volume (Vte) and positive inspiratory pressure (IPAP), with Trilogy 100 ventilator, Respironics®. The programming and recording of the variables was carried out in 8 opportunities in each group by independent operators. There was no decrease in facial pressure with any of the protective patches compared to the control group. Moltopren increased facial pressure at all support points (p < 0.001), increased leakage, it decreased MIF, Vte and IPAP (p < 0.001). Hydrocolloid patches increased facial pressure only in the left cheekbone, increased leakage and decreased MIF. Polyurethane patches did not produce changes in facial pressure or ventilatory variables. The use of protective patches of moltopren, hydrocolloid and polyurethane transparent did not contribute to the decrease of the facial pressure. A deleterious effect of the moltopren and hydrocolloid patches was observed on the administration of ventilatory variables, concluding that the non-use of the protective patches allowed a better administration of the programmed parameters.
ERIC Educational Resources Information Center
Mohammadi, Hadi
2014-01-01
Use of the Patch Vulnerability Management (PVM) process should be seriously considered for any networked computing system. The PVM process prevents the operating system (OS) and software applications from being attacked due to security vulnerabilities, which lead to system failures and critical data leakage. The purpose of this research is to…
Microstrip Antenna for Remote Sensing of Soil Moisture and Sea Surface Salinity
NASA Technical Reports Server (NTRS)
Ramhat-Samii, Yahya; Kona, Keerti; Manteghi, Majid; Dinardo, Steven; Hunter, Don; Njoku, Eni; Wilson, Wiliam; Yueh, Simon
2009-01-01
This compact, lightweight, dual-frequency antenna feed developed for future soil moisture and sea surface salinity (SSS) missions can benefit future soil and ocean studies by lowering mass, volume, and cost of the antenna system. It also allows for airborne soil moisture and salinity remote sensors operating on small aircraft. While microstrip antenna technology has been developed for radio communications, it has yet to be applied to combined radar and radiometer for Earth remote sensing. The antenna feed provides a key instrument element enabling high-resolution radiometric observations with large, deployable antennas. The design is based on the microstrip stacked-patch array (MSPA) used to feed a large, lightweight, deployable, rotating mesh antenna for spaceborne L-band (approximately equal to 1 GHz) passive and active sensing systems. The array consists of stacked patches to provide dual-frequency capability and suitable radiation patterns. The stacked-patch microstrip element was designed to cover the required L-band center frequencies at 1.26 GHz (lower patch) and 1.413 GHz (upper patch), with dual-linear polarization capabilities. The dimension of patches produces the required frequencies. To achieve excellent polarization isolation and control of antenna sidelobes for the MSPA, the orientation of each stacked-patch element within the array is optimized to reduce the cross-polarization. A specialized feed-distribution network was designed to achieve the required excitation amplitude and phase for each stacked-patch element.
Comparison of open and laparoscopic preperitoneal repair of groin hernia.
Li, Jianwen; Wang, Xin; Feng, Xueyi; Gu, Yan; Tang, Rui
2013-12-01
Compared with laparoscopic groin herniorrhaphy, the open procedure used in most former studies was Lichtenstein repair. However, unlike the totally extraperitoneal (TEP) or transabdominal preperitoneal (TAPP) laparoscopic techniques, Lichtenstein procedure is a premuscular but not preperitoneal repair. This retrospective study compared the outcomes between laparoscopic preperitoneal and open preperitoneal procedure-modified Kugel (MK) herniorrhaphy. Groin hernia patients older than 18 years who underwent open MK or laparoscopic preperitoneal herniorrhaphy in our hospitals between January 2008 and December 2010 were enrolled. Baseline characteristics, recurrence, and intraoperative, short-term, and long-term postoperative complications were recorded. Among the 1,760 included patients (530 open and 1,230 laparoscopic), 96.08% completed the follow-up (24-60 months). The patients in the open group were older than laparoscopic group (p < 0.001). More bilateral (91.45%) and recurrent (82.12%) hernia patients underwent laparoscopic procedures (p < 0.001 and p = 0.004, respectively). The overall recurrence rate was 0.71%, with no significant difference between the two approaches (p = 0.227). The overall complication rate was lower for the laparoscopic than the open approach (14.47 vs. 19.25%, p = 0.012), whereas the rates of life-threatening complications were similar (1.51 vs. 0.98%, p = 0.332). The laparoscopic group had significantly lower incidence rates of wound infection and chronic pain (p = 0.016 and p < 0.001, respectively), shorter operative time, lower visual analogue scale scores, and faster recovery than the open group (p < 0.001). As preperitoneal herniorrhaphy, both MK and laparoscopic (TEP/TAPP) procedures are safe and effective, with low incidence rates of life-threatening complications and recurrence. The laparoscopic approach is superior in terms of lower incidence rates of infection and chronic pain, shorter operative time, and faster recovery; however, careful surgical procedure selection and implementation of technical details are required.
Wearable Inset-Fed FR4 Microstrip Patch Antenna Design
NASA Astrophysics Data System (ADS)
Zaini, S. R. Mohd; Rani, K. N. Abdul
2018-03-01
This project proposes the design of a wireless body area network (WBAN) microstrip patch antenna covered by the jeans fabric as the outer layer operating at the center frequency, fc of 2.40 GHz. Precisely, the microstrip patch antenna with the inset-fed edge technique is designed and simulated systematically by using the Keysight Advanced Design System (ADS) software where the FR4 board with the dielectric constant, ɛr of 4.70, dissipation factor or loss tangent, tan δ of 0.02 and height, h of 1.60 mm is the chosen dielectric substrate. The wearable microstrip patch antenna design is then fabricated using the FR4 printed circuit board (PCB) material, hidden inside the jeans fabric, and attached to clothing, such as a jacket accordingly. Simulation and fabrication measurement results show that the designed microstrip patch antenna characteristics can be applied significantly within the industrial, scientific, and medical (ISM) radio band, which is at fc = 2.40 GHz.
An improved broadband E patch microstrip antenna for wireless communications
NASA Astrophysics Data System (ADS)
Bzeih, Amer; Chahine, Soubhi Abou; Kabalan, Karim Y.; El-Hajj, Ali; Chehab, Ali
2007-12-01
A broadband probe-fed microstrip antenna with E-shaped patch on a single-layer air substrate is investigated. Bandwidth enhancement of the antenna is achieved by inserting two parallel slots into its radiating patch. The effects of the antenna parameters are analyzed, and their optimal values for broadband operation are obtained. The design parameters are formulated as a function of the center frequency, and the empirical equations are validated by simulation. A 51.5% enhanced E patch antenna for modern wireless communications (Personal Communications Service, Digital Cellular System, Universal Mobile Telecommunications System, Wireless Local Area Network 802.11 b/g, and Bluetooth) is designed, simulated, fabricated, and measured. A comparison between simulated and measured results is presented, and it showed satisfactory agreement. Moreover, the effect of incorporating more parallel slots into the radiating patch is investigated. The antenna is designed and simulated for different scenarios (four slots, six slots, and eight slots), where a bandwidth of 57% is achieved in the eight-slot design.
Smooth causal patches for AdS black holes
NASA Astrophysics Data System (ADS)
Raju, Suvrat
2017-06-01
We review the paradox of low energy excitations of a black hole in anti-de Sitter space (AdS). An appropriately chosen unitary operator in the boundary theory can create a locally strong excitation near the black hole horizon, whose global energy is small as a result of the gravitational redshift. The paradox is that this seems to violate a general rule of statistical mechanics, which states that an operator with energy parametrically smaller than k T cannot create a significant excitation in a thermal system. When we carefully examine the position dependence of the boundary unitary operator that produces the excitation and the bulk observable necessary to detect the anomalously large effect, we find that they do not both fit in a single causal patch. This follows from a remarkable property of position-space AdS correlators that we establish explicitly and resolves the paradox in a generic state of the system, since no combination of observers can both create the excitation and observe its effect. As a special case of our analysis, we show how this resolves the "Born rule" paradox of Marolf and Polchinski [J. High Energy Phys. 01 (2016) 008, 10.1007/JHEP01(2016)008] and we verify our solution using an independent calculation. We then consider boundary states that are finely tuned to display a spontaneous excitation outside the causal patch of the infalling observer, and we propose a version of causal patch complementarity in AdS/CFT that resolves the paradox for such states as well.
NASA Astrophysics Data System (ADS)
Bhardwaj, Dheeraj; Saraswat, Shriti; Gulati, Gitansh; Shekhar, Snehanshu; Joshi, Kanika; Sharma, Komal
2016-03-01
In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S11) have been investigated. The antenna design is primarily focused on achieving a dual band operation.
Apollo 13 Astronaut Fred Haise and Apollo 13 Mission Patch
NASA Technical Reports Server (NTRS)
2000-01-01
Astronaut Fred Haise Jr. of Biloxi, Miss., views his Apollo 13 mission patch, the flight on which he served in 1970, in a StenniSphere display donated to NASA by the American Needlepoint Guild. The exhibit is on permanent display at StenniSphere, the visitor center at John C. Stennis Space Center. In its first year of operation, more than 251,000 visitors representing over 40 countries have viewed the 123 hand-stitched patches in the exhibit. Forty-two guild members from 20 states made the trip to StenniSphere for the opening of the exhibit, one of the most popular at StenniSphere.
Practical issues in the implementation of electro-mechanical impedance technique for NDE
NASA Astrophysics Data System (ADS)
Bhalla, Suresh; Naidu, Akshay S. K.; Ong, Chin W.; Soh, Chee-Kiong
2002-11-01
The electro-mechanical impedance (EMI) technique, which utilizes "smart" piezoceramic (PZT) patches as collocated actuator-sensors, has recently emerged as a powerful technique for diagnosing incipient damages in structures and machines. This technique utilizes the electro-mechanical admittance of a PZT patch surface bonded to the structure as the diagnostic signature of the structure. The operating frequency is typically maintained in the kHz range for optimum sensitivity in damage detection. However, there are many impediments to the practical application of the technique for NDE of real-life structures, such as aerospace systems, machine parts, and civil-infrastructures like buildings and bridges. The main challenge lies in achieving consistent behavior of the bonded PZT patch over sufficiently long periods, typically of the order of years, under "harsh" environment. This necessitates protecting the PZT patch from environmental effects. This paper reports a dedicated investigation stretched over several months to ascertain the long-term consistency of the electro-mechanical admittance signatures of PZT patches. Possible protection of the patch by means of suitable covering layer as well as the effects of the layer on damage sensitivity of the patch are also investigated. It is found that a suitable cover is necessary to protect the PZT patch, especially against humidity and to ensure long life. It is also found that the patch exhibits a high sensitivity to damage even in the presence of the protection layer. The paper also includes a brief discussion on few recent applications of the EMI technique and possible use of multiplexing to optimize sensor interrogation time.
Ka-Band Parabolic Deployable Antenna (KaPDA) Enabling High Speed Data Communication for CubeSats
NASA Technical Reports Server (NTRS)
Sauder, Jonathan F.; Chahat, Nacer; Hodges, Richard; Thomson, Mark W.; Rahmat-Samii, Yahya
2015-01-01
CubeSats are at a very exciting point as their mission capabilities and launch opportunities are increasing. But as instruments become more advanced and operational distances between CubeSats and earth increase communication data rate becomes a mission-limiting factor. Improving data rate has become critical enough for NASA to sponsor the Cube Quest Centennial Challenge when: one of the key metrics is transmitting as much data as possible from the moon and beyond Currently, many CubeSats communicate on UHF bands and those that have high data rate abilities use S-band or X-band patch antennas. The CubeSat Aneas, which was launched in September 2012, pushed the envelope with a half-meter S-band dish which could achieve 100x the data rate of patch antennas. A half-meter parabolic antenna operating at Ka-band would increase data rates by over 100x that of the AMOS antenM and 10,000 that of X-band patch antennas.
1949-09-08
error from this source can be substantially reduced by the use of polystyrene insulating materials in the plugboard system of problem patching (Section...present at some point in the machine (see Section 5b). -10- ( 1 d ~ PLUGBOARD Our experience ·with the operation of the REAC indicates that...utilization of the machine could be very significantly increased by a drastic revision of the patch bay. We propose to install a separable plugboard which
NASA Astrophysics Data System (ADS)
Godin, M. A.; Ryan, J. P.; Zhang, Y.; Bellingham, J. G.
2012-12-01
Observing plankton in their drifting frame of reference permits effective studies of marine ecology from the perspective of microscopic life itself. By minimizing variation caused simply by advection, observations in a plankton-tracking frame of reference focus measurement capabilities on the processes that influence the life history of populations. Further, the patchy nature of plankton populations motivates use of sensor data in real-time to resolve patch boundaries and adapt observing resources accordingly. We have developed capabilities for population-centric plankton observation and sampling by autonomous underwater vehicles (AUVs). Our focus has been on phytoplankton populations, both because of their ecological significance - as the core of the oceanic food web and yet potentially harmful under certain bloom conditions, as well as the accessibility of their signal to simple optical sensing. During the first field deployment of these capabilities in 2010, we tracked a phytoplankton patch containing toxigenic diatoms and found that their toxicity correlated with exposure to resuspended sediments. However, this first deployment was labor intensive as the AUV drove in a pre-programmed pattern centered around a patch-marking drifter; it required a boat deployment of the patch-marking drifter and required full-time operators to periodically estimate of the position of the patch with respect to the drifter and adjust the AUV path accordingly. In subsequent field experiments during 2011 and 2012, the Tethys-class long-range AUVs ran fully autonomous patch tracking algorithms which detected phytoplankton patches and continually updated estimates of each patch center by driving adaptive patterns through the patch. Iterations of the algorithm were generated to overcome the challenges of tracking advecting and evolving patches while minimizing human involvement in vehicle control. Such fully autonomous monitoring will be necessary to perform long-term in-situ observation of the full growth and decay cycle of bloom patches. Doing so will enhance our understanding of the temporal and spatial dynamics of bloom patches and the observable conditions that lead to bloom formation, ultimately improving our ability to predict the evolution of harmful algal blooms (HABs) and provide warnings for the fishing and tourism industries.
NASA Astrophysics Data System (ADS)
Mohammadi, Hadi
Use of the Patch Vulnerability Management (PVM) process should be seriously considered for any networked computing system. The PVM process prevents the operating system (OS) and software applications from being attacked due to security vulnerabilities, which lead to system failures and critical data leakage. The purpose of this research is to create and design a Security and Critical Patch Management Process (SCPMP) framework based on Systems Engineering (SE) principles. This framework will assist Information Technology Department Staff (ITDS) to reduce IT operating time and costs and mitigate the risk of security and vulnerability attacks. Further, this study evaluates implementation of the SCPMP in the networked computing systems of an academic environment in order to: 1. Meet patch management requirements by applying SE principles. 2. Reduce the cost of IT operations and PVM cycles. 3. Improve the current PVM methodologies to prevent networked computing systems from becoming the targets of security vulnerability attacks. 4. Embed a Maintenance Optimization Tool (MOT) in the proposed framework. The MOT allows IT managers to make the most practicable choice of methods for deploying and installing released patches and vulnerability remediation. In recent years, there has been a variety of frameworks for security practices in every networked computing system to protect computer workstations from becoming compromised or vulnerable to security attacks, which can expose important information and critical data. I have developed a new mechanism for implementing PVM for maximizing security-vulnerability maintenance, protecting OS and software packages, and minimizing SCPMP cost. To increase computing system security in any diverse environment, particularly in academia, one must apply SCPMP. I propose an optimal maintenance policy that will allow ITDS to measure and estimate the variation of PVM cycles based on their department's requirements. My results demonstrate that MOT optimizes the process of implementing SCPMP in academic workstations.
Microstrip Yagi Antenna with Dual Aperture-Coupled Feed
NASA Technical Reports Server (NTRS)
Pogorzelski, Ronald; Venkatesan, Jaikrishna
2008-01-01
A proposed microstrip Yagi antenna would operate at a frequency of 8.4 GHz (which is in the X band) and would feature a mechanically simpler, more elegant design, relative to a prior L-band microstrip Yagi antenna. In general, the purpose of designing a microstrip Yagi antenna is to combine features of a Yagi antenna with those of a microstrip patch to obtain an antenna that can be manufactured at low cost, has a low profile, and radiates a directive beam that, as plotted on an elevation plane perpendicular to the antenna plane, appears tilted away from the broadside. Such antennas are suitable for flush mounting on surfaces of diverse objects, including spacecraft, aircraft, land vehicles, and computers. Stated somewhat more precisely, what has been proposed is a microstrip antenna comprising an array of three Yagi elements. Each element would include four microstrip-patch Yagi subelements: one reflector patch, one driven patch, and two director patches. To obtain circular polarization, each driven patch would be fed by use of a dual offset aperture-coupled feed featuring bow-tie-shaped apertures. The selection of the dual offset bow-tie aperture geometry is supported by results found in published literature that show that this geometry would enable matching of the impedances of the driven patches to the 50-Omega impedance of the microstrip feedline while maintaining a desirably large front-to-back lobe ratio.
A High Sensitivity Three-Dimensional-Shape Sensing Patch Prepared by Lithography and Inkjet Printing
Huang, Yi-Ren; Kuo, Sheng-An; Stach, Michal; Liu, Chia-Hsing; Liao, Kuan-Hsun; Lo, Cheng-Yao
2012-01-01
A process combining conventional photolithography and a novel inkjet printing method for the manufacture of high sensitivity three-dimensional-shape (3DS) sensing patches was proposed and demonstrated. The supporting curvature ranges from 1.41 to 6.24 × 10−2 mm−1 and the sensing patch has a thickness of less than 130 μm and 20 × 20 mm2 dimensions. A complete finite element method (FEM) model with simulation results was calculated and performed based on the buckling of columns and the deflection equation. The results show high compatibility of the drop-on-demand (DOD) inkjet printing with photolithography and the interferometer design also supports bi-directional detection of deformation. The 3DS sensing patch can be operated remotely without any power consumption. It provides a novel and alternative option compared with other optical curvature sensors. PMID:22666025
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhardwaj, Dheeraj, E-mail: dbhardwaj.bit@gmail.com; Saraswat, Shriti, E-mail: saraswat.srishti@gmail.com; Gulati, Gitansh, E-mail: gitanshgulati@gmail.com
In this paper a dual band planar antenna has been proposed for IEEE 802.16 Wi-MAX /IEEE 802.11 WLAN/4.9 GHz public safety applications. The antenna comprises a frequency bandwidth of 560MHz (3.37GHz-3.93GHz) for WLAN and WiMAX and 372MHz (4.82GHz-5.192GHz) for 4.9 GHz public safety applications and Radio astronomy services (4.8-4.94 GHz). The proposed antenna constitutes of a single microstrip patch reactively loaded with three identical steps positioned in a zig-zag manner towards the radiating edges of the patch. The coaxially fed patch antenna characteristics (radiation pattern, antenna gain, antenna directivity, current distribution, S{sub 11}) have been investigated. The antenna design is primarily focused onmore » achieving a dual band operation.« less
Toytziaridis, Andreas; Dicko, Cedric
2016-01-01
The fabrication of silk-based membranes that are stable, optically transparent and reusable is yet to be achieved. To address this bottleneck we have developed a method to produce transparent chromogenic silk patches that are optically responsive to pH. The patches were produced by blending regenerated silk fibroin (RSF), Laponite RD (nano clay) and the organic dyes neutral red and Thionine acetate. The Laponite RD played a central role in the patch mechanical integrity and prevention of dye leaching. The process was optimized using a factorial design to maximize the patch response to pH by UV absorbance and fluorescence emission. New patches of the optimized protocol, made from solutions containing 125 μM neutral red or 250 μM of Thionine and 15 mg/mL silk, were further tested for operational stability over several cycles of pH altering. Stability, performance, and reusability were achieved over the tested cycles. The approach could be extended to other reporting molecules or enzymes able to bind to Laponite. PMID:27854303
NASA Technical Reports Server (NTRS)
Schwartz, Susan K.
1992-01-01
The Solid Modeling Aerospace Research Tool (SMART) is a computer aided design tool used in aerospace vehicle design. Modeling of structural components using SMART includes the representation of the transverse or cross-wise elements of a vehicle's fuselage, ringframes, and bulkheads. Ringframes are placed along a vehicle's fuselage to provide structural support and maintain the shape of the fuselage. Bulkheads are also used to maintain shape, but are placed at locations where substantial structural support is required. Given a Bezier curve representation of a cross sectional cut through a vehicle's fuselage and/or an internal tank, this project produces a first-guess Bezier patch representation of a ringframe or bulkhead at the cross-sectional position. The grid produced is later used in the structural analysis of the vehicle. The graphical display of the generated patches allows the user to edit patch control points in real time. Constraints considered in the patch generation include maintaining 'square-like' patches and placement of longitudinal, or lengthwise along the fuselage, structural elements called longerons.
NASA Technical Reports Server (NTRS)
Yueh, Simon H.; Wilson, William J.; Njoku, Eni; Hunter, Don; Dinardo, Steve; Kona, Keerti S.; Manteghi, Majid; Gies, Dennis; Rahmat-Samii, Yahya
2004-01-01
The development of a compact, lightweight, dual frequency antenna feed for future soil moisture and sea surface salinity (SSS) missions is described. The design is based on the microstrip stacked-patch array (MSPA) to be used to feed a large lightweight deployable rotating mesh antenna for spaceborne L-band (approx. 1 GHz) passive and active sensing systems. The design features will also enable applications to airborne sensors operating on small aircrafts. This paper describes the design of stacked patch elements, 16-element array configuration and power-divider beam forming network The test results from the fabrication of stacked patches and power divider were also described.
NASA Astrophysics Data System (ADS)
Rambe, A. H.; Abdillah, K.
2018-02-01
This paper discussed a low profile rectangular patch microstrip antenna design working on dual-band 1.8 GHz and 2.4 GHz. Dual-band characteristic is achieved by using inset-feed point and slot size adjustment. The designed antenna was printed on a FR4 substrate with relative permittivity of 4.4 and a thickness of 1.6 mm with patch size 40 x 29 mm. The measurement results show that the realized antenna successfully working on dual-band, achieving bandwidth of 45 MHz and 95 MHz, gain of 4.08 dBi and 5.79 dBi for 1.8 GHz and 2.4 GHz subsequently.
Structures in Ionospheric Number Density and Velocity Associated with Polar Cap Ionization Patches
NASA Technical Reports Server (NTRS)
Kivanc, O.; Heelis, R. A.
1997-01-01
Spectral characteristics of polar cap F region irregularities on large density gradients associated with polar ionization patches are studied using in situ measurements made by the Dynamics Explorer 2 (DE 2) spacecraft. The 18 patches studied in this paper were identified by the algorithm introduced by Coley and Heelis, and they were encountered during midnight-noon passes of the spacecraft. Density and velocity spectra associated with these antisunward convecting patches are analyzed in detail. Observations indicate the presence of structure on most patches regardless of the distance between the patch and the cusp where they are believed to develop. Existence of structure on both leading and trailing edges is established when such edges exist. Results, which show no large dependence of Delta N/N power on the sign of the edge gradient del N, do not allow the identification of leading and trailing edges of the patch. The Delta N/N is an increasing function of gradient del N regardless of the sign of the gradient. The correlation between Delta N/N and Delta V is generally poor, but for a given intensity in Delta V, Delta N/N maximizes in regions of large gradients in N. There is evidence for the presence of unstructured patches that seem to co-exist with unstructured horizontal velocities. Slightly smaller spectral indices for trailing edges support the presence of the E X B drift instability. Although this instability is found to be operating in some cases, results suggest that stirring may be a significant contributor to kilometer-size structures in the polar cap.
NASA Astrophysics Data System (ADS)
Aïssa, B.; Nedil, M.; Habib, M. A.; Haddad, E.; Jamroz, W.; Therriault, D.; Coulibaly, Y.; Rosei, F.
2013-08-01
This letter describes the fabrication and characterization of a fluidic patch antenna operating at the S-band frequency (4 GHz). The antenna prototype is composed of a nanocomposite material made by a liquid metal alloy (eutectic gallium indium) blended with single-wall carbon-nanotube (SWNTs). The nanocomposite is then enclosed in a polymeric substrate by employing the UV-assisted direct-writing technology. The fluidic antennas specimens feature excellent performances, in perfect agreement with simulations, showing an increase in the electrical conductivity and reflection coefficient with respect to the SWNTs concentration. The effect of the SWNTs on the long-term stability of antenna's mechanical properties is also demonstrated.
Warshaw, Erin M; Hagen, Solveig L; Belsito, Donald V; DeKoven, Joel G; Maibach, Howard I; Mathias, C G Toby; Zug, Kathryn A; Sasseville, Denis; Zirwas, Matthew J; Fowler, Joseph F; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Taylor, James S
Little is known about the epidemiology of contact dermatitis (CD) in print machine operators (PMOs). The aims of this study were to estimate the prevalence of CD and characterize clinically relevant and occupationally related allergens among PMOs undergoing patch testing. This was a retrospective cross-sectional analysis of the North American Contact Dermatitis Group data from 1998 to 2014. Of 39,332 patch-tested patients, 132 (0.3%) were PMOs. Among PMOs, most were male (75.0%) and white (92.4%). The majority were printing press operators (85.6%). The most frequent sites of dermatitis were hands (63.6%), arms (29.5%), and face/scalp (24.2%). More than half had an occupationally related skin condition (56.1%). Final diagnoses were most commonly allergic CD (58.3%) and irritant CD (33.3%). Cobalt (20.8%), carba mix (12.5%), thiuram mix (8.3%), and formaldehyde (8.3%) were the most frequent occupationally related allergens. The top allergen sources included inks (22.9%), gloves (20.8%), and coatings/dye/copy/photographic chemicals (14.6%). Allergic CD, irritant CD, and involvement of exposed body areas were common among PMOs. Common allergens included rubber accelerators, metals, and preservatives.
Patches of Remnant Frost/Snow on Crater Rim in Northern Summer
NASA Technical Reports Server (NTRS)
1999-01-01
March 1999--it is summer in the martian northern hemisphere, yet patches of frost or snow persist in some areas of the northern plains. Winter ended eight months earlier, in July 1998. Recently, the Mars Orbiter Camera (MOC) passed over a relatively small impact crater located at latitude 68oN (on the Vastitas Borealis plain, north of Utopia Planitia) and took the picture seen at the left, above. The curved crater rims are visible in the upper and lower quarters of the image, and the crater floor is visible at the center right. The picture on the right is a magnified view of the crater rim area outlined by a white box in the image on the left. The bright patches are snow or frost left over from the martian winter. These snowfields are so small that a human could walk across one of them in a matter of minutes--or perhaps sled down the small, sloping patch that is seen in a shadowed area near the lower left. In winter, the entire scene shown here would be covered by frost. The long strip at the left covers an area 3 km (1.9 mi) wide by 26 km (16 mi) long. The expanded view on the right covers an area 2.9 km (1.8 mi) by 5.3 km (3.3 mi). Illumination is from the upper right. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.Compact CPW-fed spiral-patch monopole antenna with tuneable frequency for multiband applications
NASA Astrophysics Data System (ADS)
Beigi, P.; Nourinia, J.; Zehforoosh, Y.
2018-04-01
A frequency reconfigurable monopole antenna with coplanar waveguide-fed with four switchable for multiband application is reported. The monopole antenna includes square-spiral patch and two L-shaped elements. The number of frequency resonances are increased by adding square spiral. In the reported antenna, two PIN diodes are used to achieve the multiband operation. PIN diodes embedded on the spiral patch can control the frequency resonance when they are forward-biased or in those off-state. The final designed antenna, with compact size of 20 × 20 ×1 mm3, has been fabricated on an inexpensive FR4 substrate. All experimental and simulation results are acceptable suggesting that the reported antenna is a good candidate for multiband applications.
Design of modified pentagonal patch antenna on defective ground for Wi-Max/WLAN application
NASA Astrophysics Data System (ADS)
Rawat, Sanyog; Sharma, K. K.
2016-04-01
This paper presents the design and performance of a modified pentagonal patch antenna with defective ground plane. A pentagonal slot is inserted in the pentagonal patch and slot loaded ground through optimized dimensions is used in the antenna to resonate it at dual frequency. The geometry operates at two resonant frequencies (2.5 GHz and 5.58 GHz) and offers impedance bandwidth of 864 MHz and 554 MHz in the two bands of interest. The proposed antenna covers the lower band (2.45 to 2.484/2.495 to 2.695 GHz) and upper band (5.15 to 5.825 GHz/5.25 to 5.85 GHz) allocated for Wi-Max and WLAN communication systems.
Consultation or corruption? The ethics of signing on to the medical-industrial complex.
Jones, James W; McCullough, Laurence B; Richman, Bruce W
2006-01-01
A prominent vascular surgeon is approached by a representative of a large medical device company with a proposal to implant a new self-sealing patch for closing open carotid endarterectomies. The patch is made of a new synthetic material that establishes immediate hemostasis and inhibits restenosis in animal studies. It has just been approved for human use by the Food and Drug Administration. The cost of the new patch is much higher than for established comparable products, even when potential long-term benefits are considered, but using it would reduce the operative time required for achieving hemostasis. The manufacturer's representative tells you that the company will pay a selected group of vascular surgeons $500 apiece each time they insert the patch on their patients and complete a one-page report. Surgeons with the highest volume of cases utilizing the patch will be offered a paid clinical consultancy with the company. You've used another company's product for several years and found it entirely satisfactory, but have followed development of the new patch with interest and considered trying it in your patients having carotid endarterectomies. What should you do? A. Join the study. You probably would have used the new patch on your patients anyway. B. If the early data warrant, implant the patch on a trial basis without enrolling in the project, and finally decide whether to continue using it based on your clinical experience and additional published reports. C. Call some of the other investigators who have already enrolled in the project and ask them about their experience. D. Decline the invitation immediately. Refuse to ever speak to the representative again. E. Estimate the ability of your patients to sustain the high cost of the new product and decide accordingly whether to use it.
Dual-Band Operation of a Microstrip Patch Antenna on a Duroid 5870 Substrate for Ku- and K-Bands
Islam, M. M.; Islam, M. T.; Faruque, M. R. I.
2013-01-01
The dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands is presented. The fabrication of the proposed antenna is performed with slots and a Duroid 5870 dielectric substrate and is excited by a 50 Ω microstrip transmission line. A high-frequency structural simulator (HFSS) is used which is based on the finite element method (FEM) in this research. The measured impedance bandwidth (2 : 1 VSWR) achieved is 1.07 GHz (15.93 GHz–14.86 GHz) on the lower band and 0.94 GHz (20.67–19.73 GHz) on the upper band. A stable omnidirectional radiation pattern is observed in the operating frequency band. The proposed prototype antenna behavior is discussed in terms of the comparisons of the measured and simulated results. PMID:24385878
Dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands.
Islam, M M; Islam, M T; Faruque, M R I
2013-01-01
The dual-band operation of a microstrip patch antenna on a Duroid 5870 substrate for Ku- and K-bands is presented. The fabrication of the proposed antenna is performed with slots and a Duroid 5870 dielectric substrate and is excited by a 50 Ω microstrip transmission line. A high-frequency structural simulator (HFSS) is used which is based on the finite element method (FEM) in this research. The measured impedance bandwidth (2 : 1 VSWR) achieved is 1.07 GHz (15.93 GHz-14.86 GHz) on the lower band and 0.94 GHz (20.67-19.73 GHz) on the upper band. A stable omnidirectional radiation pattern is observed in the operating frequency band. The proposed prototype antenna behavior is discussed in terms of the comparisons of the measured and simulated results.
NASA Astrophysics Data System (ADS)
Oiknine, Yaniv; August, Isaac Y.; Revah, Liat; Stern, Adrian
2016-05-01
Recently we introduced a Compressive Sensing Miniature Ultra-Spectral Imaging (CS-MUSI) system. The system is based on a single Liquid Crystal (LC) cell and a parallel sensor array where the liquid crystal cell performs spectral encoding. Within the framework of compressive sensing, the CS-MUSI system is able to reconstruct ultra-spectral cubes captured with only an amount of ~10% samples compared to a conventional system. Despite the compression, the technique is extremely complex computationally, because reconstruction of ultra-spectral images requires processing huge data cubes of Gigavoxel size. Fortunately, the computational effort can be alleviated by using separable operation. An additional way to reduce the reconstruction effort is to perform the reconstructions on patches. In this work, we consider processing on various patch shapes. We present an experimental comparison between various patch shapes chosen to process the ultra-spectral data captured with CS-MUSI system. The patches may be one dimensional (1D) for which the reconstruction is carried out spatially pixel-wise, or two dimensional (2D) - working on spatial rows/columns of the ultra-spectral cube, as well as three dimensional (3D).
Rectangular Microstrip Antenna with Slot Embedded Geometry
NASA Astrophysics Data System (ADS)
Ambresh, P. A.; Hadalgi, P. M.; Hunagund, P. V.; Sujata, A. A.
2014-09-01
In this paper, a novel design that improves the performance of conventional rectangular microstrip antenna is discussed. Design adopts basic techniques such as probe feeding technique with rectangular inverted patch structure as superstrate, air filled dielectric medium as substrate and slot embedded patch. Prototype of the proposed antenna has been fabricated and various antenna performance parameters such as impedance bandwidth, return loss, radiation pattern and antenna gain are considered for Electromagnetic-study. The antennas are designed for the wireless application operating in the frequency range of 3.3 GHz to 3.6 GHz, and UK based fixed satellite service application (3 GHz to 4 GHz), and are named as single inverted patch conventional rectangular microstrip antenna (SIP-CRMSA) and slots embedded inverted patch rectangular microstrip antenna (SEIP-RMSA), respectively. Measurement outcomes for SEIP-RMSA1 and SEIP-RMSA2 showed the satisfactory performance with an achievable impedance bandwidth of 260 MHz (7 %) and 250 MHz (6.72 %), with return loss (RL) of -11.06 dB and -17.98 dB, achieved gain of 8.17 dB and 5.17 dB with 10% and 8% size reduction in comparison with the conventional patch antenna.
Asymmetric patch size distribution leads to disruptive selection on dispersal.
Massol, François; Duputié, Anne; David, Patrice; Jarne, Philippe
2011-02-01
Numerous models have been designed to understand how dispersal ability evolves when organisms live in a fragmented landscape. Most of them predict a single dispersal rate at evolutionary equilibrium, and when diversification of dispersal rates has been predicted, it occurs as a response to perturbation or environmental fluctuation regimes. Yet abundant variation in dispersal ability is observed in natural populations and communities, even in relatively stable environments. We show that this diversification can operate in a simple island model without temporal variability: disruptive selection on dispersal occurs when the environment consists of many small and few large patches, a common feature in natural spatial systems. This heterogeneity in patch size results in a high variability in the number of related patch mates by individual, which, in turn, triggers disruptive selection through a high per capita variance of inclusive fitness. Our study provides a likely, parsimonious and testable explanation for the diversity of dispersal rates encountered in nature. It also suggests that biological conservation policies aiming at preserving ecological communities should strive to keep the distribution of patch size sufficiently asymmetric and variable. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.
UV-cured adhesives for carbon fiber composite applications
NASA Astrophysics Data System (ADS)
Lu, Hsiao-Chun
Carbon fiber composite materials are increasingly used in automobile, marine, and aerospace industries due to their unique properties, including high strength, high stiffness and low weight. However, due to their brittle characteristic, these structures are prone to physical damage, such as a bird strike or impact damage. Once the structure is damaged, it is important to have fast and reliable temporary repair until the permanent repair or replacement can take place. In this dissertation, UV-based adhesives were used to provide a bonding strength for temporary repair. Adhesively bonded patch repair is an efficient and effective method for temporary repair. In this study, precured patches (hard patches) and dry fabric patches with laminating resins (soft patches) were performed. UV-based epoxy adhesives were applied to both patch repair systems. For precured patch repair, the bonding strengths were investigated under different surface treatments for bonding area and different adhesives thicknesses. The shear stresses of different UV exposure times and curing times were tested. Besides, the large patch repair was investigated as well. For soft patch repair, the hand wet lay-up was applied due to high viscosity of UV resins. A modified single lap shear testing (ASTM D5868) was applied to determine the shear stress. The large patches used fiber glass instead of carbon fiber to prove the possibility of repair with UV epoxy resin by hand wet lay-up process. The hand lay-up procedure was applied and assisted by vacuum pressure to eliminate the air bubbles and consolidate the patches. To enhance the bonding strength and effective soft patch repair, vacuum assisted resin transferring molding (VaRTM) is the better option. However, only low viscosity resins can be operated by VaRTM. Hence, new UV-based adhesives were formulated. The new UV-based adhesives included photoinitiator (PI), epoxy and different solvents. Solvents were used to compound the photoinitiator into epoxy monomer. Acetone, tetrahydrofuran (THF) and chloroform were used as well as their anhydrous solvents. The UV exposure times and curing times of new UV-based resins were tested. FT-IR, DSC and DMA were used to investigate structure, glass transition temperatures(Tg) and properties of polymer. In summary, the UV-based adhesive was applied to adhesively bonded hard patch and soft patch repair. In addition, new UV-based resins were formulated for the VaRTM process. The in-field repair can be effective and efficient by using UV adhesives.
An operational amplifier B1404UD1A-1 in the patch-clamp current-to-voltage converter.
Korzun, A M; Rozinov, S V; Abashin, G I
1997-01-01
The applicability of the home-made operational amplifier B1404UD1A-1 in a patch-clamp current-to-voltage converter was analyzed. Its parameters (background noise, input bias current, and gain-bandwidth product) were estimated. Schematic solutions and practical recommendations for the use of this amplifier in a current-to-voltage converter were given. Based on the background noise and frequency parameters of the converter, we found that this device can be used for measuring ion channel currents with a high sensitivity and within a broad frequency range (0.055 pA, to 1 kHz; 0.4 pA, to 10 kHz). An example of the converter application in experiments is given.
The endoventricular circular patch plasty ("Dor procedure") in ischemic akinetic dilated ventricles.
Dor, V
2001-09-01
From 1984 to 2000, 950 Left Ventricular ischemic asynergy (dyskinetic or akinetic) were operated using the endoventricular circular patch plasty technique. This allows to exclude all asynergic areas of the left ventricular wall and reshape the remaining wall. Both morphology and hemodynamic of left ventricle, are improved. Hospital mortality was below 7%. Life expectancy at 10 years reaches 80% if pre-operative L.V.E.F. is above 30%, and end systolic volume index (E.S.V.I.) below 90[emsp4 ]ml, and 60% in L.V.E.F. is below 30% and E.S.V.I. above 90[emsp4 ]ml. L.V.R. by endoventricular plasty has to be considered in the treatment of ischemic congestive heart failure.
Stripline feed for a microstrip array of patch elements with teardrop shaped probes
NASA Technical Reports Server (NTRS)
Huang, John (Inventor)
1990-01-01
A circularly polarized microstrip array antenna utilizing a honeycomb substrate made of dielectric material to support on one side the microstrip patch elements in an array, and on the other side a stripline circuit for feeding the patch elements in subarray groups of four with angular orientation and phase for producing circularly polarized radiation, preferably at a 0.degree., 90.degree., 180.degree. and 270.degree. relationship. The probe used for coupling each feed point in the stripline circuit to a microstrip patch element is teardrop shaped in order to introduce capacitance between the coupling probe and the metal sheet of the stripline circuit that serves as an antenna ground plane. The capacitance thus introduced tunes out inductance of the probe. The shape of the teardrop probe is not critical. The probe capacitance required is controlled by the maximum diameter for the teardrop shaped probe, which can be empirically determined for the operating frequency. An aluminum baffle around each subarray blocks out surface waves between subarrays.
Surgery-Related Contact Dermatitis: A Review of Potential Irritants and Allergens.
Cook, Kevin A; Kelso, John M
Surgical procedures utilize an increasing number of medical products including antiseptics, anesthetics, gloves, suture materials, tissue adhesives, topical antibiotics, and bandages. Many of these products have irritant potential. Allergic contact dermatitis has also been reported. This review covers preoperative, operative, and postoperative exposures that may result in contact dermatitis. Testing with standard patch panels such as T.R.U.E. Test and the North American Contact Dermatitis Group 65 allergen series does not evaluate for all relevant contactants. A thorough understanding of potential exposures is vital to effectively evaluate a patient with surgery-related contact dermatitis. A systematic approach is needed to ensure that standard patch panels and supplementary patches adequately address each encountered contactant. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.
Patch Transporter: Incentivized, Decentralized Software Patch System for WSN and IoT Environments
Lee, JongHyup
2018-01-01
In the complicated settings of WSN (Wireless Sensor Networks) and IoT (Internet of Things) environments, keeping a number of heterogeneous devices updated is a challenging job, especially with respect to effectively discovering target devices and rapidly delivering the software updates. In this paper, we convert the traditional software update process to a distributed service. We set an incentive system for faithfully transporting the patches to the recipient devices. The incentive system motivates independent, self-interested transporters for helping the devices to be updated. To ensure the system correctly operates, we employ the blockchain system that enforces the commitment in a decentralized manner. We also present a detailed specification for the proposed protocol and validate it by model checking and simulations for correctness. PMID:29438337
Patch Transporter: Incentivized, Decentralized Software Patch System for WSN and IoT Environments.
Lee, JongHyup
2018-02-13
[-12]In the complicated settings of WSN (Wireless Sensor Networks) and IoT (Internet of Things) environments, keeping a number of heterogeneous devices updated is a challenging job, especially with respect to effectively discovering target devices and rapidly delivering the software updates. In this paper, we convert the traditional software update process to a distributed service. We set an incentive system for faithfully transporting the patches to the recipient devices. The incentive system motivates independent, self-interested transporters for helping the devices to be updated. To ensure the system correctly operates, we employ the blockchain system that enforces the commitment in a decentralized manner. We also present a detailed specification for the proposed protocol and validate it by model checking and simulations for correctness.
Analysis of Microstrip Line Fed Patch Antenna for Wireless Communications
NASA Astrophysics Data System (ADS)
Singh, Ashish; Aneesh, Mohammad; Kamakshi; Ansari, J. A.
2017-11-01
In this paper, theoretical analysis of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator is presented. The proposed antenna shows that the dualband operation depends on gap between parasitic element, split-ring resonator, length and width of microstrip line. It is found that antenna resonates at two distinct resonating modes i.e., 0.9 GHz and 1.8 GHz for lower and upper resonance frequencies respectively. The antenna shows dual frequency nature with frequency ratio 2.0. The characteristics of microstrip line fed rectangular patch antenna loaded with parasitic element and split-ring resonator antenna is compared with other prototype microstrip line fed antennas. Further, the theoretical results are compared with simulated and reported experimental results, they are in close agreement.
Patch depletion, niche structuring and the evolution of co-operative foraging
2011-01-01
Background Many animals live in groups. One proposed reason is that grouping allows cooperative food finding. Group foraging models suggest that grouping could increase food finding rates, but that such group processes could be evolutionarily unstable. These models assume discrete food patches which are fully detectable. However, often animals may only be able to perceive local parts of larger-scale environmental patterns. We therefore use a spatial individual-based model where food patches are aggregates of food items beyond the scale of individual perception. We then study the evolution of foraging and grouping behavior in environments with different resource distributions. Results Our results show that grouping can evolve to increase food intake rates. Two kinds of grouping evolve: traveling pairs and opportunistic grouping, where individuals only aggregate when feeding. Grouping evolves because it allows individuals to better sense and deplete patches. Such enhanced patch depletion is particularly apparent on fragmented and partially depleted patches, which are especially difficult for solitary foragers to deplete. Solitary foragers often leave a patch prematurely because a whole patch cannot be observed directly. In groups, individuals that are still eating allow other individuals that inadvertently leave the patch, to return and continue feeding. For this information sharing a grouping tendency is sufficient and observing whether a neighbor is eating is not necessary. Grouping therefore leads to a release from individual sensing constraints and a shift in niche specialization, allowing individuals to better exploit partially depleted patches. Conclusions The evolved group foraging can be seen as cooperative in the sense that it leads to a mutually-beneficial synergy: together individuals can achieve more than on their own. This cooperation exists as a group-level process generated by the interaction between grouping and the environment. Thus we reveal how such a synergy can originate in evolution as a side-effect of grouping via multi-level selection. Here there is no cooperative dilemma as individuals cannot avoid producing information for their neighbors. This scenario may be a useful starting point for studying the evolution of further social and cooperative complexity. PMID:22093680
Lundblad, Runar; Abdelnoor, Michel; Svennevig, Jan Ludvig
2004-09-01
Simple linear resection and endoventricular patch plasty are alternative techniques to repair postinfarction left ventricular aneurysm. The aim of the study was to compare these 2 methods with regard to early mortality and long-term survival. We retrospectively reviewed 159 patients undergoing operations between 1989 and 2003. The epidemiologic design was of an exposed (simple linear repair, n = 74) versus nonexposed (endoventricular patch plasty, n = 85) cohort with 2 endpoints: early mortality and long-term survival. The crude effect of aneurysm repair technique versus endpoint was estimated by odds ratio, rate ratio, or relative risk and their 95% confidence intervals. Stratification analysis by using the Mantel-Haenszel method was done to quantify confounders and pinpoint effect modifiers. Adjustment for multiconfounders was performed by using logistic regression and Cox regression analysis. Survival curves were analyzed with the Breslow test and the log-rank test. Early mortality was 8.2% for all patients, 13.5% after linear repair and 3.5% after endoventricular patch plasty. When adjusted for multiconfounders, the risk of early mortality was significantly higher after simple linear repair than after endoventricular patch plasty (odds ratio, 4.4; 95% confidence interval, 1.1-17.8). Mean follow-up was 5.8 +/- 3.8 years (range, 0-14.0 years). Overall 5-year cumulative survival was 78%, 70.1% after linear repair and 91.4% after endoventricular patch plasty. The risk of total mortality was significantly higher after linear repair than after endoventricular patch plasty when controlled for multiconfounders (relative risk, 4.5; 95% confidence interval, 2.0-9.7). Linear repair dominated early in the series and patch plasty dominated later, giving a possible learning-curve bias in favor of patch plasty that could not be adjusted for in the regression analysis. Postinfarction left ventricular aneurysm can be repaired with satisfactory early and late results. Surgical risk was lower and long-term survival was higher after endoventricular patch plasty than simple linear repair. Differences in outcome should be interpreted with care because of the retrospective study design and the chronology of the 2 repair methods.
Patch mosaic burning for biodiversity conservation: a critique of the pyrodiversity paradigm.
Parr, Catherine L; Andersen, Alan N
2006-12-01
Fire management is increasingly focusing on introducing heterogeneity in burning patterns under the assumption that "pyrodiversity begets biodiversity." This concept has been formalized as patch mosaic burning (PMB), in which fire is manipulated to create a mosaic of patches representative of a range of fire histories to generate heterogeneity across space and time. Although PMB is an intuitively appealing concept, it has received little critical analysis. Thus we examined ecosystems where PMB has received the most attention and has been the most extensively implemented: tropical and subtropical savannas of Australia and Africa. We identified serious shortcomings of PMB: the ecological significance of different burning patterns remains unknown and details of desired fire mosaics remain unspecified. This has led to fire-management plans based on pyrodiversity rhetoric that lacks substance in terms of operational guidelines and capacity for meaningful evaluation. We also suggest that not all fire patterns are ecologically meaningful: this seems particularly true for the highly fire-prone savannas of Australia and South Africa. We argue that biodiversity-needs-pyrodiversity advocacy needs to be replaced with a more critical consideration of the levels of pyrodiversity needed for biodiversity and greater attention to operational guidelines for its implementation.
Non-Intrusive, Distributed Gas Sensing Technology for Advanced Spacesuits
NASA Technical Reports Server (NTRS)
Delgado, Jesus; Phillips, Straun; Rubtsov, Vladimir; Chullen, Cinda
2015-01-01
Chemical sensors for monitoring gas composition, including oxygen, humidity, carbon dioxide, and trace contaminants are needed to characterize and validate spacesuit design and operating parameters. This paper reports on the first prototypes of a non-intrusive gas sensing technology based on flexible sensitive patches positioned inside spacesuit prototypes and interrogated by optical fibers routed outside the suit, taking advantage of the transparent materials of the suit prototypes. The sensitive patches are based on luminescent materials whose emission parameters vary with the partial pressure of a specific gas. Patches sensitive to carbon dioxide, humidity, oxygen, and ammonia have been developed, and their preliminary characterization in the laboratory using Mark III-like helmet parts is described. The first prototype system consists of a four-channel fiber optic luminescent detector that can be used to monitor any of the selected target gases at four locations. To switch from one gas to another we replace the (disposable) sensor patches and adjust the system settings. Repeatability among sensitive patches and of sensor performance from location to location has been confirmed, assuring that suit engineers will have flexibility in selecting multiple sensing points, fitting the sensor elements into the spacesuit, and easily repositioning the sensor elements as desired. The evaluation of the first prototype for monitoring carbon dioxide during washout studies in a space suit prototype is presented.
QPatch: the past, present and future of automated patch clamp.
Mathes, Chris
2006-04-01
The QPatch 16 significantly increases throughput for gigaseal patch clamp experiments, making direct measurements in ion channel drug discovery and safety testing feasible. Released to the market in the Autumn of 2004 by Sophion Bioscience, the QPatch originated from work done at NeuroSearch (Denmark) in the early days of automated patch clamp. Today, the QPatch provides many unique features. For example, only the QPatch includes an automated cell preparation station making several hours of unattended operation possible. The 16-channel electrode array, called the QPlate, includes glass-coated microfluidic channels for less compound absorption and, hence, more accurate IC(50) values. The microfluidic pathways also allow for very small amounts of compound used for each experiment ( approximately 5 microl per addition). Only the QPatch has four independent pipetting heads for more efficient liquid handling (especially for ligand-gated ion channel experiments). Patch clamp recordings with the QPatch match the high quality of conventional patch clamp and in some cases the results are even better. For example, only the QPatch includes 100% series resistance compensation for the elimination of false positives due to voltage errors. Finally, the modular QPatch 16 was designed with more channels in mind. The upgrade pathway to 48-channels (the QPatch HT) will be discussed.
Non-Intrusive, Distributed Gas Sensing Technology for Advanced Spacesuits
NASA Technical Reports Server (NTRS)
Delgado, Jesus; Phillips, Straun; Rubtsov, Vladimir; Chullen, Cinda
2015-01-01
Chemical sensors for monitoring gas composition, including oxygen, humidity, carbon dioxide, and trace contaminants, are needed to characterize and validate spacesuit design and operating parameters. This paper reports on the first prototypes of a non-intrusive gas sensing technology based on flexible sensitive patches positioned inside spacesuit prototypes and interrogated via optical fibers routed outside the suit, taking advantage of the transparent materials of the suit prototypes. The sensitive patches are based on luminescent materials whose emission parameters vary with the partial pressure of a specific gas. Patches sensitive to carbon dioxide, humidity, and temperature have been developed, and their preliminary laboratory characterization in Mark III-like helmet parts is described. The first prototype system consists of a four-channel fiber optic luminescent detector that can be used to monitor any of the selected target gases at four locations. To switch from one gas to another we replace the (disposable) sensor patches and adjust the system settings. Repeatability among sensitive patches and of sensor performance from location to location has been confirmed, assuring that suit engineers will have flexibility in selecting multiple sensing points, fitting the sensor elements into the spacesuit, and easily repositioning the sensor elements as desired. The evaluation of the first prototype for monitoring carbon dioxide during washout studies in a spacesuit prototype is presented.
Buprenorphine Transdermal Patch
... it to direct heat such as heating pads, electric blankets, heat lamps, saunas, hot tubs, and heated ... may make you drowsy. Do not drive a car, operate machinery, or do other possibly dangerous activities ...
... other sources of heat such as heating pads, electric blankets and heated waterbeds; or direct sunlight. Do ... you suddenly fall asleep. Do not drive a car or operate machinery at the beginning of your ...
[The course of melanization and its inhibition in pupae of the cabbage whitePieris brassicae L.
Bückmann, Detlef
1971-09-01
The melanization of the Cabbage White pupae varies in response to light conditions. As abdomina, which are isolated by a ligature, become strongly melanized, the control evidently works in the way of gradual inhibition.The melanine patches of light pupae are not paler than those of dark pupae, but they are smaller. Apparently there is a gradient of reactivity to inhibition from the margin of the patches towards their center. Different patches are affected by the inhibition to a different extent.The black patches appear during the first 6 hours after pupation, not simultaneously but in a certain sequence. The first and the last patches of this sequence are most reactive to inhibition. On light pupae they may be entirely absent.A classification of pupal melanization is based on differences in the shape of certain patches, which can easily be recognized even on operated pupae and isolated parts of the body.Equally strong melanization as from ligating results from nerve section between brain an suboesophageal ganglion, somewhat weaker melanization results from section between suboesophageal and prothoracic ganglia.The melanizing effects of ligatures and nerve sections decrease during a critical period. They are entirely lost 12 hours after the prepupa has fastened itself to the ground by spinning the girdle-thread.It is suggested that during this critical period a melanization inhibiting factor is secreted by a thoracic center, which itself is under nervous control of the brain.
NASA Astrophysics Data System (ADS)
Popov, Fedor K.
2018-06-01
We calculate the one-loop contributions to the polarization operator for scalar quantum electrodynamics in different external electromagnetic and gravitational fields. In the case of gravity, de Sitter space and its different patches were considered. It is shown that the Debye mass appears only in the case of alpha-vacuum in the Expanding Poincare Patch. It can be shown either by direct computations or by using analytical and causal properties of the de Sitter space. Also, the case of constant electric field is considered and the Debye mass is calculated.
WMSA for wireless communication applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vats, Monika; Agarwal, Alok, E-mail: alokagarwal26@yahoo.com; Kumar, Ravindra
2016-03-09
Modified rectangular compact microstrip patch antenna having finite ground plane is proposed in this paper. Wideband Microstrip Antenna (WMSA) is achieved by corner cut and inserting air gaps inside the edges of the radiating patch having finite ground plane. The obtained impedance bandwidth for 10 dB return loss for the operating frequency f{sub 0} = 2.09 GHz is 28.7 % (600 MHz), which is very high as compared to the bandwidth obtained for the conventional microstrip antenna. Compactness with wide bandwidth of this antenna is practically useful for the wireless communication systems.
Microelectromechanical Systems (MEMS) Actuators for Antenna Reconfigurability
NASA Technical Reports Server (NTRS)
Simons, Rainee N.; Chun, Donghoon; Katehi, Linda P. B.
2001-01-01
A novel microelectromechanical systems (MEMS) actuator for patch antenna reconfiguration, is presented for the first time. A key feature is the capability of multi-band operation without greatly increasing the antenna element dimensions. Experimental results demonstrate that the center frequency can be reconfigured from few hundred MHz to few GHz away from the nominal operating frequency.
The study of microstrip antenna arrays and related problems
NASA Technical Reports Server (NTRS)
Lo, R. Q.
1984-01-01
The work on rectangular microstrip antennas for dual frequency operation is reported on. The principle of this approach is based on the excitation of a patch for two or more different modes which correspond to different frequencies. However, for a given geometry, the modal frequencies have a fixed relationship; therefore, the usefulness of such a design is greatly limited. In this study three different methods have been contrived to control the frequency ratio over a wide range. First, as found prevously, if shorting pins are inserted at certain locations in the patch, the low frequency can be raised substantially. Second, if slots are cut in the patch, the high frequency can be lowered considerably. By using both techniques, the two frequency ratio can be varied approximately from 3 to 1.3. After that, the addition of more pins or slots becomes ineffective.
NASA Astrophysics Data System (ADS)
Smith, Joshua Wyatt; Stewart, Graeme A.; Seuster, Rolf; Quadt, Arnulf; ATLAS Collaboration
2017-10-01
This paper reports on the port of the ATLAS software stack onto new prototype ARM64 servers. This included building the “external” packages that the ATLAS software relies on. Patches were needed to introduce this new architecture into the build as well as patches that correct for platform specific code that caused failures on non-x86 architectures. These patches were applied such that porting to further platforms will need no or only very little adjustments. A few additional modifications were needed to account for the different operating system, Ubuntu instead of Scientific Linux 6 / CentOS7. Selected results from the validation of the physics outputs on these ARM 64-bit servers will be shown. CPU, memory and IO intensive benchmarks using ATLAS specific environment and infrastructure have been performed, with a particular emphasis on the performance vs. energy consumption.
Optimal patch code design via device characterization
NASA Astrophysics Data System (ADS)
Wu, Wencheng; Dalal, Edul N.
2012-01-01
In many color measurement applications, such as those for color calibration and profiling, "patch code" has been used successfully for job identification and automation to reduce operator errors. A patch code is similar to a barcode, but is intended primarily for use in measurement devices that cannot read barcodes due to limited spatial resolution, such as spectrophotometers. There is an inherent tradeoff between decoding robustness and the number of code levels available for encoding. Previous methods have attempted to address this tradeoff, but those solutions have been sub-optimal. In this paper, we propose a method to design optimal patch codes via device characterization. The tradeoff between decoding robustness and the number of available code levels is optimized in terms of printing and measurement efforts, and decoding robustness against noises from the printing and measurement devices. Effort is drastically reduced relative to previous methods because print-and-measure is minimized through modeling and the use of existing printer profiles. Decoding robustness is improved by distributing the code levels in CIE Lab space rather than in CMYK space.
Patch Network for Power Allocation and Distribution in Smart Materials
NASA Technical Reports Server (NTRS)
Golembiewski, Walter T.
2000-01-01
The power allocation and distribution (PAD) circuitry is capable of allocating and distributing a single or multiple sources of power over multi-elements of a power user grid system. The purpose of this invention is to allocate and distribute power that is collected by individual patch rectennas to a region of specific power-user devices, such as actuators. The patch rectenna converts microwave power into DC power. Then this DC power is used to drive actuator devices. However, the power from patch rectennas is not sufficient to drive actuators unless all the collected power is effectively used to drive another group by allocation and distribution. The power allocation and distribution (PAD) circuitry solves the shortfall of power for devices in a large array. The PAD concept is based on the networked power control in which power collected over the whole array of rectennas is allocated to a sub domain where a group of devices is required to be activated for operation. Then the allocated power is distributed to individual element of power-devices in the sub domain according to a selected run-mode.
NASA Astrophysics Data System (ADS)
Kganyago, Mahlatse; Odindi, John; Adjorlolo, Clement; Mhangara, Paidamoyo
2018-05-01
Globally, there is paucity of accurate information on the spatial distribution and patch sizes of Invasive Alien Plants (IAPs) species. Such information is needed to aid optimisation of control mechanisms to prevent further spread of IAPs and minimize their impacts. Recent studies have shown the capability of very high spatial (<1 m) and spectral resolution (<10 nm) data for discriminating vegetation species. However, very high spatial resolution may introduce significant intra-species spectral variability and result in reduced mapping accuracy, while higher spectral resolution data are commonly limited to smaller areas, are costly and computationally expensive. Alternatively, medium and high spatial resolution data are available at low or no cost and have limitedly been evaluated for their potential in determining invasion patterns relevant for invasion ecology and aiding effective IAPs management. In this study medium and high resolution datasets from Landsat Operational Land Imager (OLI) and SPOT 6 sensors respectively, were evaluated for mapping the distribution and patch sizes of IAP, Parthenium hysterophorus in the savannah landscapes of KwaZulu-Natal, South Africa. Support Vector Machines (SVM) classifier was used for classification of both datasets. Results indicated that SPOT 6 had a higher overall accuracy (86%) than OLI (83%) in mapping P. hysterophorus. The study found larger distributions and patch sizes in OLI than in SPOT 6 as a result of possible P. hysterophorus expansion due to temporal differences between images and coarser pixels were insufficient to delineate gaps inside larger patches. On the other hand, SPOT 6 showed better capabilities of delineating gaps and boundaries of patches, hence had better estimates of distribution and patch sizes. Overall, the study showed that OLI may be suitable for mapping well-established patches for the purpose of large scale monitoring, while SPOT 6 can be used for mapping small patches and prioritising them for eradication to prevent further spread at a landscape scale.
Polar Dunes In Summer Exhibit Frost Patches, Wind Streaks
NASA Technical Reports Server (NTRS)
1999-01-01
Mars Global Surveyor passes over the north polar region of the red planet twelve times each day, offering many opportunities to observe how the polar cap frosts and dunes are changing as the days goby. Right now it is summer in the north. This picture, taken the second week of April 1999, shows darks and dunes and remnant patches of bright frost left over from the winter that ended in July 1998. Dark streaks indicate recent movement of sand. The picture covers an area only 1.4 kilometers (0.9 miles)across and is illuminated from the upper right. Malin Space Science Systems and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.Long range ultra-high frequency (UHF) radio frequency identification (RFID) antenna design
NASA Astrophysics Data System (ADS)
Reynolds, Nathan D.
There is an ever-increasing demand for radio frequency identification (RFID) tags that are passive, long range, and mountable on multiple surfaces. Currently, RFID technology is utilized in numerous applications such as supply chain management, access control, and public transportation. With the combination of sensory systems in recent years, the applications of RFID technology have been extended beyond tracking and identifying. This extension includes applications such as environmental monitoring and healthcare applications. The available sensory systems usually operate in the medium or high frequency bands and have a low read range. However, the range limitations of these systems are being overcome by the development of RFID sensors focused on utilizing tags in the ultra-high frequency (UHF) band. Generally, RFID tags have to be mounted to the object that is being identified. Often the objects requiring identification are metallic. The inherent properties of metallic objects have substantial effects on nearby electromagnetic radiation; therefore, the operation of the tag antenna is affected when mounted on a metallic surface. This outlines one of the most challenging problems for RFID systems today: the optimization of tag antenna performance in a complex environment. In this research, a novel UHF RFID tag antenna, which has a low profile, long range, and is mountable on metallic surfaces, is designed analytically and simulated using a 3-D electromagnetic simulator, ANSYS HFSS. A microstrip patch antenna is selected as the antenna structure, as patch antennas are low profile and suitable for mounting on metallic surfaces. Matching and theoretical models of the microstrip patch antenna are investigated. Once matching and theory of a microstrip patch antenna is thoroughly understood, a unique design technique using electromagnetic band gap (EBG) structures is explored. This research shows that the utilization of an EBG structure in the patch antenna design yields an improvement in gain, or range, and in the ability to be mounted on multiple metallic surfaces.
Reconfigurable Array Antenna Using Microelectromechanical Systems (MEMS) Actuators
NASA Technical Reports Server (NTRS)
Simons, Rainee N.; Chun, Donghoon; Katehi, Linda P. B.
2001-01-01
The paper demonstrates a patch antenna integrated with a novel microelectromechanical systems (MEMS) actuator for reconfiguring the operating frequency. Experimental results demonstrate that the center frequency can be reconfigured by as much as 1.6 percent of the nominal operating frequency at K-Band In addition, a novel on-wafer antenna pattern measurement technique is demonstrated.
Development of a Remote External Repair Tool for Damaged or Defective Polyethylene Pipe
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kenneth H. Green; Willie E. Rochefort; Nick Wannenmacher
2006-06-30
Current procedures for repairing polyethylene (PE) gas pipe require excavation, isolation, and removal of the damaged section of pipe followed by fusing a new section of pipe into place. These techniques are costly and very disruptive. An alternative repair method was developed at Timberline Tool with support from Oregon State University (OSU) and funding by the U. S. Department of Energy National Energy Technology Laboratory (DOE/NETL). This project was undertaken to design, develop and test a tool and method for repairing damaged PE pipe remotely and externally in situ without squeezing off the flow of gas, eliminating the need formore » large-scale excavations. Through an iterative design and development approach, a final engineered prototype was developed that utilizes a unique thermo-chemical and mechanical process to apply a permanent external patch to repair small nicks, gouges and punctures under line pressure. The project identified several technical challenges during the design and development process. The repair tool must be capable of being installed under live conditions and operate in an 18-inch keyhole. This would eliminate the need for extensive excavations thus reducing the cost of the repair. Initially, the tool must be able to control the leak by encapsulating the pipe and apply slight pressure at the site of damage. Finally, the repair method must be permanent at typical operating pressures. The overall results of the project have established a permanent external repair method for use on damaged PE gas pipe in a safe and cost-effective manner. The engineered prototype was subjected to comprehensive testing and evaluation to validate the performance. Using the new repair tool, samples of 4-inch PE pipe with simulated damage were successfully repaired under line pressure to the satisfaction of DOE/NETL and the following natural gas companies: Northwest Natural; Sempra Energy, Southwest Gas Corporation, Questar, and Nicor. However, initial results of accelerated age testing on repaired pipe samples showed that the high density polyethylene (HDPE) pipe patch material developed a small crack at the high stress areas surrounding the patched hole within the first 48 hours of hot water testing, indicating that the patch material has a 25-year lifespan. Based on these results, further research is continuing to develop a stronger repair patch for a satisfactory 50-year patch system. Additional tests were also conducted to evaluate whether any of the critical performance properties of the PE pipe were reduced or compromised by the repair technique. This testing validated a satisfactory 50-year patch system for the pipe.« less
Bhaskar, Hemant; Kapoor, Pranav; Ragini
2010-01-01
Aims: This study was performed to compare the degree of post operative analgesia, patient compliance, and frequency of adverse events with the use of oral diclofenac tablets and transdermal diclofenac patch following multiple premolar extractions in patients undergoing orthodontic treatment. Materials and Methods: Twenty young pre-orthodontic patients requiring bilateral maxillary and mandibular first premolar extractions were selected for the study. The right maxillary and mandibular first premolars were extracted first and 50 mg oral diclofenac sodium tablets were prescribed to be taken thrice a day for three days. In the next appointment, the contralateral first premolars were extracted and a 100 mg transdermal diclofenac patch was applied once a day for three days. Pain relief and pain intensity with both the diclofenac formulations was recorded for each of the three postoperative days using 5-point Verbal Pain Intensity and Pain Relief Score Charts. Results and Conclusions: Statistical analyses revealed that there was a gradual increase in pain relief scores and a gradual decrease in pain intensity scores with the use of oral diclofenac tablets as well as with the transdermal patch. However, subjects reported that they were more comfortable using the transdermal patch particularly due to the once-a-day application and lesser frequency of systemic adverse effects. Results of this study indicate that the transdermal diclofenac patch provides as potent analgesia as the oral diclofenac tablets with the added advantage of better patient compliance and may be used for routine post extraction analgesia. PMID:22114407
de Sitter space as a tensor network: Cosmic no-hair, complementarity, and complexity
NASA Astrophysics Data System (ADS)
Bao, Ning; Cao, ChunJun; Carroll, Sean M.; Chatwin-Davies, Aidan
2017-12-01
We investigate the proposed connection between de Sitter spacetime and the multiscale entanglement renormalization ansatz (MERA) tensor network, and ask what can be learned via such a construction. We show that the quantum state obeys a cosmic no-hair theorem: the reduced density operator describing a causal patch of the MERA asymptotes to a fixed point of a quantum channel, just as spacetimes with a positive cosmological constant asymptote to de Sitter space. The MERA is potentially compatible with a weak form of complementarity (local physics only describes single patches at a time, but the overall Hilbert space is infinite dimensional) or, with certain specific modifications to the tensor structure, a strong form (the entire theory describes only a single patch plus its horizon, in a finite-dimensional Hilbert space). We also suggest that de Sitter evolution has an interpretation in terms of circuit complexity, as has been conjectured for anti-de Sitter space.
Broadband Circularly Polarized Slot Antenna Loaded by a Multiple-Circular-Sector Patch
Trinh-Van, Son; Yang, Youngoo; Lee, Kang-Yoon
2018-01-01
In this paper, a microstrip-fed broadband circularly polarized (CP) slot antenna is presented. CP operation can be attained simply by embedding an S-shaped strip. By loading with a multiple-circular-sector patch, which consists of 12 circular-sector patches with identical central angles of 30° and different radii, the 3 dB axial ratio (AR) bandwidth is significantly broadened. To validate the performance of the proposed antenna, an antenna prototype is fabricated and tested. The fabricated antenna is 54 mm × 54 mm × 0.8 mm in size. The measured −10 dB reflection and 3 dB AR bandwidths are 81.06% (1.68–3.97 GHz) and 70.55% (1.89–3.95 GHz), respectively. Within the 3 dB AR bandwidth, the measured peak gain is 3.81 dBic. Reasonable agreement is also obtained between the measured and simulated results. PMID:29762530
Broadband Circularly Polarized Slot Antenna Loaded by a Multiple-Circular-Sector Patch.
Trinh-Van, Son; Yang, Youngoo; Lee, Kang-Yoon; Hwang, Keum Cheol
2018-05-15
In this paper, a microstrip-fed broadband circularly polarized (CP) slot antenna is presented. CP operation can be attained simply by embedding an S-shaped strip. By loading with a multiple-circular-sector patch, which consists of 12 circular-sector patches with identical central angles of 30° and different radii, the 3 dB axial ratio (AR) bandwidth is significantly broadened. To validate the performance of the proposed antenna, an antenna prototype is fabricated and tested. The fabricated antenna is 54 mm × 54 mm × 0.8 mm in size. The measured -10 dB reflection and 3 dB AR bandwidths are 81.06% (1.68⁻3.97 GHz) and 70.55% (1.89⁻3.95 GHz), respectively. Within the 3 dB AR bandwidth, the measured peak gain is 3.81 dBic. Reasonable agreement is also obtained between the measured and simulated results.
Dredging displaces bottlenose dolphins from an urbanised foraging patch.
Pirotta, Enrico; Laesser, Barbara Eva; Hardaker, Andrea; Riddoch, Nicholas; Marcoux, Marianne; Lusseau, David
2013-09-15
The exponential growth of the human population and its increasing industrial development often involve large scale modifications of the environment. In the marine context, coastal urbanisation and harbour expansion to accommodate the rising levels of shipping and offshore energy exploitation require dredging to modify the shoreline and sea floor. While the consequences of dredging on invertebrates and fish are relatively well documented, no study has robustly tested the effects on large marine vertebrates. We monitored the attendance of common bottlenose dolphins (Tursiops truncatus) to a recently established urbanised foraging patch, Aberdeen harbour (Scotland), and modelled the effect of dredging operations on site usage. We found that higher intensities of dredging caused the dolphins to spend less time in the harbour, despite high baseline levels of disturbance and the importance of the area as a foraging patch. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Dormer, James D.; Halicek, Martin; Ma, Ling; Reilly, Carolyn M.; Schreibmann, Eduard; Fei, Baowei
2018-02-01
Cardiovascular disease is a leading cause of death in the United States. The identification of cardiac diseases on conventional three-dimensional (3D) CT can have many clinical applications. An automated method that can distinguish between healthy and diseased hearts could improve diagnostic speed and accuracy when the only modality available is conventional 3D CT. In this work, we proposed and implemented convolutional neural networks (CNNs) to identify diseased hears on CT images. Six patients with healthy hearts and six with previous cardiovascular disease events received chest CT. After the left atrium for each heart was segmented, 2D and 3D patches were created. A subset of the patches were then used to train separate convolutional neural networks using leave-one-out cross-validation of patient pairs. The results of the two neural networks were compared, with 3D patches producing the higher testing accuracy. The full list of 3D patches from the left atrium was then classified using the optimal 3D CNN model, and the receiver operating curves (ROCs) were produced. The final average area under the curve (AUC) from the ROC curves was 0.840 +/- 0.065 and the average accuracy was 78.9% +/- 5.9%. This demonstrates that the CNN-based method is capable of distinguishing healthy hearts from those with previous cardiovascular disease.
Design, simulation and analysis a microstrip antenna using PU-EFB substrate
NASA Astrophysics Data System (ADS)
Mahmud, S. N. S.; Jusoh, M. A.; Jasim, S. E.; Zamani, A. H.; Abdullah, M. H.
2018-04-01
A low cost, light weight and easy to fabricate are the most important factor for future antennas. Microstrip patch antennas offer these advantages and suitable for communication and sensor application. This paper presents a design of simple microstrip patch antenna working on operating frequency of 2.4 GHz. The designed process has been carried out using MATLAB and HFSS software by entering 2.3 for the dielectric constant of PU-EFB. The results showed that high return loss, low bandwidth and good antenna radiation efficiency of which are -21.98 dB, 0.28 dB and 97.33%, respectively.
1994-10-08
Designed by the crew members, the STS-63 crew patch depicts the orbiter maneuvering to rendezvous with Russia's Space Station Mir. The name is printed in Cyrillic on the side of the station. Visible in the Orbiter's payload bay are the commercial space laboratory Spacehab and the Shuttle Pointed Autonomous Research Tool for Astronomy (SPARTAN) satellite which are major payloads on the flight. The six points on the rising sun and the three stars are symbolic of the mission's Space Transportation System (STS) numerical designation. Flags of the United States and Russia at the bottom of the patch symbolize the cooperative operations of this mission.
Cloud Particle Size and Water/Ice Ratio Estimation using the DMSP SSMIS Sounder
NASA Astrophysics Data System (ADS)
Peng, G. S.; Fote, A. A.; Wu, D. L.; Boucher, D. J.; Thomas, B. H.; Kishi, A. M.
2008-12-01
The Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave Imager/Sounder (SSMIS) is a next-generation passive conically scanning microwave radiometer. It combines both imaging and sounding capabilities of current operational instruments, SSM/I, SSM/T-1 and SSM/T-2. It also improves the capability of temperature sounding by providing profiles from the surface up to 70 km altitude with higher spatial resolutions (~37.5 for lower air and ~75 km for upper air). DMSP Flight 17 launched on 4 November 2006 from Vandenberg Air Force Base carrying the second SSMIS sounder. During the SSMIS Cal/Val period, cold patches were observed in the 50-55 GHz temperature sounding channels at low latitudes. Cold patches were also more apparent in the horizontal polarization (H- pol) than the Vertical polarization (V-pol) channels. A difference in sensitivity of the H-pol and V-pol channels gives the ratio of water to ice in the clouds. Subsequent investigation showed that these patches appeared in the 91.6 GHz channels but not the 37 GHz channels. This information, together with the theoretical scattering efficiency for spherical particles of various sizes, gives an upper bound of < 2 mm diameter for water and ice particles that may not be detected by SSMIS operational 'cloud clearing' algorithms.
A Minimized MIMO-UWB Antenna with High Isolation and Triple Band-Notched Functions
NASA Astrophysics Data System (ADS)
Kong, Yuanyuan; Li, Yingsong; Yu, Kai
2016-11-01
A compact high isolation MIMO-UWB antenna with triple frequency rejection bands is proposed for UWB communication applications. The proposed MIMO-UWB antenna consists of two identical UWB antennas and each antenna element has a semicircle ring shaped radiation patch fed by a bend microstrip feeding line for covering the UWB band, which operates from 2.85 GHz to 11.79 GHz with an impedance bandwidth of 122.1 %. By etching a L-shaped slot on the ground plane, and embedding an "anchor" shaped stub into the patch and integrating an open ring under the semicircle shaped radiation patch, three notch bands are realized to suppress WiMAX (3.3-3.6 GHz), WLAN(5.725-5.825 GHz) and uplink of X-band satellite (7.9-8.4 GHz) signals. The high isolation with S21<-20 dB in most UWB band is obtained by adding a protruded decoupling structure. The design procedure of the MIMO-UWB antenna is given in detail. The proposed MIMO-UWB antenna is simulated, fabricated and measured. Experimental results demonstrate that the proposed MIMO-UWB antenna has a stable gain, good impedance match, high isolation, low envelope correlation coefficient and good radiation pattern at the UWB operating band and it can provide three designated notch bands.
Samsuzzaman, M.; Islam, M. T.; Arshad, Haslina; Mandeep, J. S.; Misran, N.
2014-01-01
Circularly polarized (CP) dual frequency cross-shaped slotted patch antenna on 1.575 mm thick glass microfiber reinforced polytetrafluoroethylene (PTFE) composite material substrate is designed and fabricated for satellite applications. Asymmetric cross-shaped slots are embedded in the middle of the square patch for CP radiation and four hexagonal slots are etched on the four sides of the square patch for desired dual frequency. Different substrate materials have been analysed to achieve the desired operating band. The experimental results show that the impedance bandwidth is approximately 30 MHz (2.16 GHz to 2.19 GHz) for lower band and 40 MHz (3.29 GHz to 3.33 GHz) for higher band with an average peak gain of 6.59 dBiC and 5.52 dBiC, respectively. Several optimizations are performed to obtain the values of the antenna physical parameters. Moreover, the proposed antenna possesses compactness, light weight, simplicity, low cost, and circularly polarized. It is an attractive candidate for dual band satellite antennas where lower band can be used for uplink and upper band can be used for downlink. PMID:24982943
A New Metasurface Superstrate Structure for Antenna Performance Enhancement.
Islam, Mohammad Tariqul; Ullah, Mohammad Habib; Singh, Mandeep Jit; Faruque, Mohammad Rashed Iqbal
2013-07-31
A new metasurface superstrate structure (MSS)-loaded dual band microstrip line-fed small patch antenna is presented in this paper. The proposed antenna was designed on a ceramic-filled bioplastic sandwich substrate with a high dielectric constant. The proposed 7 × 6 element, square-shaped, single-sided MSS significantly improved the bandwidth and gain of the proposed antenna. The proposed MSS incorporated a slotted patch antenna that effectively increased the measured operating bandwidth from 13.3% to 18.8% and from 14.8% to 23.2% in the lower and upper bands, respectively. Moreover, the average gain of the proposed MSS-based antenna was enhanced from 2.12 dBi to 3.02 dBi in the lower band and from 4.10 dBi to 5.28 dBi in the upper band compared to the patch antenna alone. In addition to the bandwidth and gain improvements, more directive radiation characteristics were also observed from the MSS antenna compared to the patch itself. The effects of the MSS elements and the ground plane length on the reflection coefficient of the antenna were analyzed and optimized. The overall performance makes the proposed antenna appropriate for RFID and WLAN applications.
A Circular Microstrip Antenna Sensor for Direction Sensitive Strain Evaluation.
Lopato, Przemyslaw; Herbko, Michal
2018-01-20
In this paper, a circular microstrip antenna for stress evaluation is studied. This kind of microstrip sensor can be utilized in structural health monitoring systems. Reflection coefficient S 11 is measured to determine deformation/strain value. The proposed sensor is adhesively connected to the studied sample. Applied strain causes a change in patch geometry and influences current distribution both in patch and ground plane. Changing the current flow in patch influences the value of resonant frequency. In this paper, two different resonant frequencies were analysed because in each case, different current distributions in patch were obtained. The sensor was designed for operating frequency of 2.5 GHz (at fundamental mode), which results in a diameter less than 55 mm. Obtained sensitivity was up to 1 MHz/100 MPa, resolution depends on utilized vector network analyser. Moreover, the directional characteristics for both resonant frequencies were defined, studied using numerical model and verified by measurements. Thus far, microstrip antennas have been used in deformation measurement only if the direction of external force was well known. Obtained directional characteristics of the sensor allow the determination of direction and value of stress by one sensor. This method of measurement can be an alternative to the rosette strain gauge.
A New Metasurface Superstrate Structure for Antenna Performance Enhancement
Islam, Mohammad Tariqul; Ullah, Mohammad Habib; Singh, Mandeep Jit; Faruque, Mohammad Rashed Iqbal
2013-01-01
A new metasurface superstrate structure (MSS)-loaded dual band microstrip line-fed small patch antenna is presented in this paper. The proposed antenna was designed on a ceramic-filled bioplastic sandwich substrate with a high dielectric constant. The proposed 7 × 6 element, square-shaped, single-sided MSS significantly improved the bandwidth and gain of the proposed antenna. The proposed MSS incorporated a slotted patch antenna that effectively increased the measured operating bandwidth from 13.3% to 18.8% and from 14.8% to 23.2% in the lower and upper bands, respectively. Moreover, the average gain of the proposed MSS-based antenna was enhanced from 2.12 dBi to 3.02 dBi in the lower band and from 4.10 dBi to 5.28 dBi in the upper band compared to the patch antenna alone. In addition to the bandwidth and gain improvements, more directive radiation characteristics were also observed from the MSS antenna compared to the patch itself. The effects of the MSS elements and the ground plane length on the reflection coefficient of the antenna were analyzed and optimized. The overall performance makes the proposed antenna appropriate for RFID and WLAN applications. PMID:28811432
Design of broadband single polarized antenna
NASA Astrophysics Data System (ADS)
Shin, Phoo Kho; Aziz, Mohamad Zoinol Abidin Abd.; Ahmad, Badrul Hisham; Ramli, Mohamad Hafize Bin; Fauzi, Noor Azamiah Md; Malek, Mohd Fareq Abd
2015-05-01
In practical wireless communication application, bandwidth enhancement becomes one of the major design considerations. At the same time, circular polarized (CP) antenna received much attention for the applications of modern wireless communication system when compared to linear polarized (LP) antenna. This is because CP antenna can reduce the multipath effect. Hence, broadband antenna with operating frequency at 2.4GHz for WLAN application is proposed. The proposed antenna is done by using L-probe amendment with rectangular patch. The rectangular patch and copper ground plane is separated with 10mm air gap. This approach is used to enhance the bandwidth and the gain of the proposed antenna. The bandwidth of the designed antenna is more than 200MHz which meet broadband application. The return loss for the antenna is below -10dB to achieved 90% matching efficiency. The position of L-probe feed is altered in order to obtained different polarizations. The broadband antenna had been designed and simulated by using Computer Simulation Technology (CST) software. In this paper, the comparison for single polarized antenna with the design of non-inverted patch and inverted patch is discussed. The characteristics of the S-parameter, axial ratio, gain, surface current for each designed antenna are analyzed.
Natural orifice transluminal endoscopic surgery for patients with perforated peptic ulcer.
Bonin, Eduardo A; Moran, Erica; Gostout, Christopher J; McConico, Andrea L; Zielinski, Martin; Bingener, Juliane
2012-06-01
Perforation accounts for 70% of deaths attributed to peptic ulcers. Laparoscopic repair is effective but infrequently used. Our aim was to assess how many patients with perforated peptic ulcer could be candidates for a transluminal endoscopic omental patch closure. This retrospective study reviewed patients with perforated peptic ulcer from 2005 to 2010. Demographics, ulcer characteristics, operative procedure, and outcomes were recorded. Candidates for endoscopic transluminal repair were defined as those having undergone omental patch closure of an ulcer of appropriate size and no contraindications to laparoscopy or endoscopy. In the retrospective review, a total of 104 patients were identified; 62% female, mean age = 68 years, mean ASA of 3, and 63% medication-related ulcers. Fifty-nine (63%) had an omental patch (80% open), and 35 (37%) had other procedures. Ten patients had nonoperative management. Thirty-day mortality was 14% and 1 year mortality was 35%. Forty-nine patients (52%) were considered potential candidates for transluminal repair. Sixty-three percent of our patients sustained a medication-related perforation with 1 year mortality of 35%. The majority of patients were treated using open omental patch repair. Transluminal endoscopic repair may provide an additional situation for a minimally invasive approach for a number of these patients.
Sandoval, John A; Lou, Derek; Engum, Scott A; Fisher, Lisa M; Bouchard, Christine M; Davis, Mary M; Grosfeld, Jay L
2006-03-01
Diaphragmatic reconstruction remains a challenging problem. There is limited information concerning the use of small intestinal submucosa (SIS) in congenital diaphragmatic hernia repair. A canine model was used to evaluate the use of a SIS patch in diaphragmatic reconstruction. Eleven beagle puppies (1.6-4.2 kg, 8 weeks old) underwent left subcostal laparotomy, central left hemidiaphragm excision (2 x 7 cm, 50% loss), and reconstruction with a 4-ply group I (n = 5) or 8-ply group II (n = 6) SIS patch. Chest radiographs were taken at time of operation and 3 and 6 months postoperatively. Animals were killed at 6 months. Adhesion formation (both pleural and abdominal), gross visual evaluation of the patch, and histology were compared. In group I (4-ply), 1 animal died at 3 months from patch deterioration accompanied by stomach herniation that resulted in respiratory failure. In the 4 remaining animals, chest radiographs showed no evidence of herniation or eventration. On physical examination, there was no evidence of chest wall deformity. During gross surgical examination, the 4-ply patches showed thinning, multiple defects, and liver herniation in 3 animals. In 1 pup, the patch was thickened, intact, well incorporated at the repair site, and adherent to the liver and spleen. In group II (8-ply), 1 animal died of cardiopulmonary failure in the early postoperative period. In the other 5 animals, chest radiographs showed evidence of eventration in 1. On gross examination the patch adhered to the liver in all 5 surviving animals. In 4, the patches were thickened, viable, but had some shrinkage. One patch pulled away from the native diaphragm laterally; however, no visceral herniation was present. In the 1 animal with eventration, there was no evidence of a patch. Adhesion scores (AS) were graded and determined by the sum of extent (0-4), type (0-4), and tenacity (0-3). Average abdominal AS in group I was 5.6 +/- 0.8 vs 10.2 +/- 0.2 (P = .079) for group II. Average lung AS was 0.6 +/- 0.6 in group I vs 3.8 +/- 1.1 (P = .0476) for group II. Histological examination showed group II patches had greater collagen deposition with central calcification and mild inflammation within the residual graft, whereas group I patches were much thinner and were composed of granulation tissue without evidence of residual graft. These data indicate that 8-ply SIS repair of diaphragmatic defects was superior (80%; 4/5 to 4-ply, 20%; 1/5, success). Organ adherence appears to be necessary for neovascularization of the SIS composite. Eight-ply grafts appear to be more durable and persist for a longer period, which may improve neovascularization. Long-term follow-up to evaluate remodeling characteristics of the patch material is required.
NASA Astrophysics Data System (ADS)
Rabbani, Muhammad Saqib; Ghafouri-Shiraz, Hooshang
2017-05-01
In this paper, ultra-wide patch antenna arrays have been presented at 60 GHz band (57.24-65.88 GHz) with improved gain and beam-width capabilities for remote detection of respiration and heart beat rate of a person with Doppler radar principle. The antennas measured and simulation results showed close agreement. The breathing rate (BR) and heart rate (HR) of a 31-year-old man have been accurately detected from various distances ranging from 5 to 200 cm with both single-antenna and dual-antenna operations. In the case of single-antenna operation, the signal is transmitted and received with the same antenna, whereas in dual-antenna operation, two identical antennas are employed, one for signal transmission and the other for reception. It has been found that in case of the single-antenna operation, the accuracy of the remote vital sign monitoring (RVSM) is good for short distance; however, in the case of the dual-antenna operations, the RVSM can be accurately carried out at relatively much longer distance. On the other hand, it has also been seen that the visual results are more obvious with higher gain antennas when the radar beam is confined just on the subject's body area.
Yildiz, Turan; Ilce, Huri Tilla; Ceran, Canan; Ilce, Zekeriya
2014-05-01
Peptic ulcer disease in children is rare. Therefore, the diagnosis can be missed until complications such as perforation or hemorrhage occur. Few reports have investigated the procedures and outcomes of children who have undergone operations for perforated duodenal ulcers. We report our experience with the modified Graham technique for perforated duodenal ulcers in nine children and review the literature. Methods : The records of patients operated on for a perforated duodenal ulcer in the last 8 years in two pediatric surgery centers were evaluated retrospectively. Patient demographics, symptoms, time to admission to hospital, operative findings, and postoperative clinical course were evaluated. Results : Nine children (mean age 13.2 years, range 6-170 years) were included. All patients were admitted in the first six hours after their abdominal pain started. In three patients, there was free air on plain x-rays, while the x-rays were normal in six. All perforations were located on the anterior surface of the first part of the duodenum and repaired with primary suturing and Graham patch omentoplasty. The recovery was uneventful in all patients. In five patients, urea breath tests were performed postoperatively for Helicobacter Pylori, and the results were positive. All patients underwent triple therapy with lansoprazole, amoxicillin, and clarithromycin. The mean follow-up time was 58 (range 3-94) months. Conclusions : Peptic ulcer perforation should be suspected in children who have acute abdominal pain and peritoneal signs, especially when their suffering is intense. The simple patch repair and postoperative triple therapy for Helicobacter Pylori are safe and satisfactory for treating peptic ulcer perforation in children.
NASA Astrophysics Data System (ADS)
Kaplan, D. A.; Casey, S. T.; Cohen, M. J.; Acharya, S.; Jawitz, J. W.
2016-12-01
A century of hydrologic modification has altered the physical and biological drivers of landscape processes in the Everglades (Florida, USA). Restoring the ridge-slough patterned landscape, a dominant feature of the historical system, is a priority, but requires an understanding of pattern genesis and degradation mechanisms. Physical experiments to evaluate alternative pattern formation mechanisms are limited by the long time scales of peat accumulation and loss, necessitating model-based comparisons, where support for a particular mechanism is based on model replication of extant patterning and trajectories of degradation. However, multiple mechanisms yield patch elongation in the direction of historical flow (a central feature of ridge-slough patterning), limiting the utility of that characteristic for discriminating among alternatives. Using data from vegetation maps, we investigated the statistical features of ridge-slough spatial patterning (ridge density, patch perimeter, elongation, patch-size distributions, and spatial periodicity) to establish more rigorous criteria for evaluating model performance and to inform controls on pattern variation across the contemporary system. Two independent analyses (2-D periodograms and patch size distributions) provide strong evidence against regular patterning, with the landscape exhibiting neither a characteristic wavelength nor a characteristic patch size, both of which are expected under conditions that produce regular patterns. Rather, landscape properties suggest robust scale-free patterning, indicating genesis from the coupled effects of local facilitation and a global negative feedback operating uniformly at the landscape-scale. This finding challenges widespread invocation of scale-dependent negative feedbacks for explaining ridge-slough pattern origins. These results help discern among genesis mechanisms and provide an improved statistical description of the landscape that can be used to compare among model outputs, as well as to assess the success of future restoration projects.
Advanced optimal design concepts for composite material aircraft repair
NASA Astrophysics Data System (ADS)
Renaud, Guillaume
The application of an automated optimization approach for bonded composite patch design is investigated. To do so, a finite element computer analysis tool to evaluate patch design quality was developed. This tool examines both the mechanical and the thermal issues of the problem. The optimized shape is obtained with a bi-quadratic B-spline surface that represents the top surface of the patch. Additional design variables corresponding to the ply angles are also used. Furthermore, a multi-objective optimization approach was developed to treat multiple and uncertain loads. This formulation aims at designing according to the most unfavorable mechanical and thermal loads. The problem of finding the optimal patch shape for several situations is addressed. The objective is to minimize a stress component at a specific point in the host structure (plate) while ensuring acceptable stress levels in the adhesive. A parametric study is performed in order to identify the effects of various shape parameters on the quality of the repair and its optimal configuration. The effects of mechanical loads and service temperature are also investigated. Two bonding methods are considered, as they imply different thermal histories. It is shown that the proposed techniques are effective and inexpensive for analyzing and optimizing composite patch repairs. It is also shown that thermal effects should not only be present in the analysis, but that they play a paramount role on the resulting quality of the optimized design. In all cases, the optimized configuration results in a significant reduction of the desired stress level by deflecting the loads away from rather than over the damage zone, as is the case with standard designs. Furthermore, the automated optimization ensures the safety of the patch design for all considered operating conditions.
Farlow, Martin R; Sadowsky, Carl H; Velting, Drew M; Meng, Xiangyi; Islam, M Zahur
2015-06-01
To identify factors predicting improvement/stabilization on the Alzheimer's Disease Cooperative Study-Clinical Global Impression of Change (ADCS-CGIC) and investigate whether early treatment responses can predict long-term outcomes, during a trial of 13.3 mg/24 h versus 4.6 mg/24 h rivastigmine patch in patients with severe Alzheimer's disease (AD). Logistic regression was used to relate Week 24 ADCS-CGIC score to potential baseline predictors. Additional analyses based on receiver-operating characteristic curves were performed using Week 8/16 ADCS-CGIC scores to predict response (13.3 mg/24 h patch) at Week 24. ADCS-CGIC score of (1) 1-3 = "improvement," (2) 1-4 = "improvement or no change". "Treatment" (13.3 mg/24 h patch) and increased age were significant predictors of "improvement" (P = 0.01 and P = 0.003, respectively), and "treatment" (P = 0.001), increased age (P = 0.002), and prior AD treatment (P = 0.03) for "improvement or no change". At Week 8 and 16, ADCS-CGIC scores of 4 and 5 were optimal thresholds in predicting "improvement," and "improvement or no change," respectively, at Week 24. A significant therapeutic effect of high-dose rivastigmine patch on ADCS-CGIC response was observed. The 13.3 mg/24 h patch was identified as a predictor of "improvement" or "improvement or no change". Patients with minimal worsening/improvement/no change after treatment initiation may be more likely to respond following long-term therapy. © 2015 John Wiley & Sons Ltd.
Distal vein patch as a form of autologus modification for infragenicular prosthetic bypass.
Totic, Dragan; Rustempasic, Nedzad; Djedovic, Muhamed; Solakovic, Sid; Vukas, Haris; Aslani, Ilijas; Krvavac, Alma; Rudalija, Dzejra; Ahmetasevic, Alen
2013-01-01
Preferred graft for infragenicular bypass is autologus vein. The problem is when there is not available autologus vein. Literature suggest that in these situations, prosthetic graft with some form of modification of distal anastomosis with autogenic tissue is valuable adjunctive. Frequently used modifications are Miller's cuff, Taylor's patch and St. Mary's boot. Recently, there are reports on "Distal vein patch" as a form of autologus modification which, due to its simplicity and patency rate, attracted attention. The aim of this study was to evaluate benefits of this novel modification by comparing its patencies with other autologus modification of distal anastomosis. Study was performed on 60 patients, diabetics, with critical limb ischemia (CLI). Patients were divided in two groups: Group with distal vein patch modification; and group with some other form modification - control group. Patients were followed at least 22 months. We examined patency of grafts by physical examination or using Color Doppler. For statistical purposes we used KIaplan Meier analysis and curve. Significance was determined by Mann-Whitney, Fisher's exact, Pearsons chi square or Student T test as appropriate. P value less than 0,05 was considered significant. Groups were fairly matched relative to demographics, risk factors, operative intervention and distal anastomosis site. There was not statistical difference in two year primary patency between distal vein patch and control group--50% vs 53% respectivly (X2 = 0,08; p = 0,773). Also, there was not statistically significant difference in extremity survival (77% vs 77%) and patient survival between groups (89% vs 93%; X2 = 2,458; p = 0,117). This study proved equivalent patencies of infragenicular prosthetic bypasses performed using distal vein patch technique as with any other modification of distal anastomosis.
Fricke, Tyson A; d'Udekem, Yves; Brizard, Christian P; Wheaton, Gavin; Weintraub, Robert G; Konstantinov, Igor E
2015-04-01
Williams syndrome is an uncommon genetic disorder associated with supravalvular aortic stenosis (SVAS) in childhood. We reviewed outcomes of children with Williams syndrome who underwent repair of SVAS during a 30-year period at a single institution. Between 1982 and 2012, 28 patients with Williams syndrome were operated on for SVAS. Mean age at operation was 5.2 years (range, 3 months to 13 years), and mean weight at operation was 18.6 kg (range, 4.1 to 72.4 kg). Associated cardiac lesions in 11 patients (39.3%) were repaired at the time of the SVAS repair. The most common associated cardiac lesion was main pulmonary artery stenosis (8 of 28 [28%]). A 3-patch repair was performed in 10 patients, a Doty repair in 17, and a McGoon repair in 1 (3.6%). There were no early deaths. Follow-up was 96% complete (27 of 28). Overall mean follow-up was 11.2 years (range, 1 month to 27.3 years). Mean follow-up was 5 years (range, 1 month to 14.3 years) for the 3-patch repair patients and 14.7 years (range, 6 weeks to 27 years) for the Doty repair patients. Of the 17 Doty patients, there were 4 (24%) late deaths, occurring at 6 weeks, 3.5 years, 4 years, and 16 years after the initial operation. There were no late deaths in the 3-patch repair patients. Overall survival was 86% at 5, 10, and 15 years after repair. Survival was 82% at 5, 10 and 15 years for the Doty repair patients. Overall, 6 of 27 patients (22%) patients required late reoperation at a mean of 11.2 years (range, 3.6 to 23 years). No 3-patch repair patients required reoperation. Overall freedom from reoperation was 91% at 5 years and 73% at 10 and 15 years. Freedom from reoperation for the Doty repair patients was 93% at 5 years and 71% at 10 and 15 years. Surgical repair of SVAS in children Williams syndrome has excellent early results. However, significant late mortality and morbidity warrants close follow-up. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
sts-130patch-design-finalthreads
2009-09-18
STS130-S-001 (September 2009) --- The STS-130 patch was designed by the crew to reflect both the objectives of the mission and its place in the history of human spaceflight. The main goal of the mission is to deliver Node 3 and the Cupola to the International Space Station (ISS). Node 3, named ?Tranquility,? will contain life support systems enabling continued human presence in orbit aboard the ISS. The shape of the patch represents the Cupola, which is the windowed robotics viewing station, from which astronauts will have the opportunity not only to monitor a variety of ISS operations, but also to study our home planet. The image of Earth depicted in the patch is the first photograph of Earth taken from the moon by Lunar Orbiter I on Aug. 23, 1966. As both a past and a future destination for explorers from planet Earth, the moon is thus represented symbolically in the STS-130 patch. The space shuttle Endeavour is pictured approaching the ISS, symbolizing the space shuttle's role as the prime construction vehicle for the ISS. The NASA insignia design for space shuttle flights is reserved for use by the astronauts and for other official use as the NASA Administrator may authorize. Public availability has been approved only in the forms of illustrations by the various news media. When and if there is any change in this policy, which is not anticipated, the change will be publicly announced. Photo credit: NASA
NASA Astrophysics Data System (ADS)
Xu, Gang; Li, Ming; Mourrain, Bernard; Rabczuk, Timon; Xu, Jinlan; Bordas, Stéphane P. A.
2018-01-01
In this paper, we propose a general framework for constructing IGA-suitable planar B-spline parameterizations from given complex CAD boundaries consisting of a set of B-spline curves. Instead of forming the computational domain by a simple boundary, planar domains with high genus and more complex boundary curves are considered. Firstly, some pre-processing operations including B\\'ezier extraction and subdivision are performed on each boundary curve in order to generate a high-quality planar parameterization; then a robust planar domain partition framework is proposed to construct high-quality patch-meshing results with few singularities from the discrete boundary formed by connecting the end points of the resulting boundary segments. After the topology information generation of quadrilateral decomposition, the optimal placement of interior B\\'ezier curves corresponding to the interior edges of the quadrangulation is constructed by a global optimization method to achieve a patch-partition with high quality. Finally, after the imposition of C1=G1-continuity constraints on the interface of neighboring B\\'ezier patches with respect to each quad in the quadrangulation, the high-quality B\\'ezier patch parameterization is obtained by a C1-constrained local optimization method to achieve uniform and orthogonal iso-parametric structures while keeping the continuity conditions between patches. The efficiency and robustness of the proposed method are demonstrated by several examples which are compared to results obtained by the skeleton-based parameterization approach.
NASA Technical Reports Server (NTRS)
1994-01-01
Designed by the crew members, the crew patch depicts the Orbiter maneuving to rendezvous with Russia's Space Station Mir. The name is printed in Cyrillic on the side of the station. Visible in the Orbiter's payload bay are the commercial space laboratory Spacehab and the Shuttle Pointed Autonomous Research Tool for Astronomy (SPARTAN) satellite which are major payloads on the flight. The six points on the rising sun and the three stars are symbolic of the mission's Space Transportation System (STS) numerical designation. Flags of the United States and Russia at the bottom of the patch symbolize the cooperative operations of this mission. The crew will be flying aboard the space shuttle Discovery.
Off-pump repair of a post-infarct ventricular septal defect: the 'Hamburger procedure'
Barker, Thomas A; Ng, Alexander; Morgan, Ian S
2006-01-01
We report a novel off-pump technique for the surgical closure of post-infarct ventricular septal defects (VSDs). The case report describes the peri-operative management of a 76 year old lady who underwent the 'Hamburger procedure' for closure of her apical VSD. Refractory cardiogenic shock meant that traditional patch repairs requiring cardiopulmonary bypass would be poorly tolerated. We show that echocardiography guided off-pump posterior-anterior septal plication is a safe, effective method for closing post-infarct VSDs in unstable patients. More experience is required to ascertain whether this technique will become an accepted alternative to patch repairs. PMID:16722552
Inverted S-Shaped Compact Antenna for X-Band Applications
Samsuzzaman, M.; Islam, M. T.
2014-01-01
A novel probe-fed compact inverted S-shaped multifrequency patch antenna is designed. By employing two rectangular slots that change the conventional rectangular patch into an inverted S-shaped patch, the antenna is able to operate in triple frequency in the X-band. The performance criteria of the proposed design have been experimentally verified by fabricating a printed prototype. The measured results show that the −10 dB impedance bandwidth of the proposed antenna at lower band is 5.02% (8.69–9.14 GHz), at middle band is 9.13% (10.47–11.48 GHz), and at upper band is 3.79% (11.53–11.98 GHz). Two elliptical slots are introduced in the ground plane to increase the peak gain. The antenna is excited by a simple probe feeding mechanism. The overall antenna dimension is 0.52λ × 0.60λ × 0.046λ at a lower resonance frequency of 9.08 GHz. The antenna configuration and parametric investigation are conducted with the help of the high frequency structural simulator, and a good agreement is achieved between the simulated and measured data. The stable gain, omnidirectional radiation pattern, and consistent radiation efficiency in the achieved operating band make the proposed antenna a suitable candidate for X-band applications. PMID:24895656
Improving microwave antenna gain and bandwidth with phase compensation metasurface
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Ke; Yang, Zhongjie; Feng, Yijun, E-mail: yjfeng@nju.edu.cn
Metasurface, as a planar version of artificial metamaterial, provide an effective way to manipulate electromagnetic wave propagation. Here, we present a transparent metasurface for compensating the out-of-phase radiation from a microstrip patch antenna to improve its radiation gain and bandwidth. Based on the equivalence principle of Huygens’ surface, we propose metasurface composed of both inductive and capacitive resonant elements which could produce high transmission with variable phase characteristics. Such metasurface mounted on a patch antenna can transform the spherical-like phase profile generated from the patch into an in-phase planar one. A prototype antenna has been fabricated and validated the squeezedmore » radiation pattern with suppressed sidelobes as well as enhanced impedance bandwidth due to strong near-field coupling. As operating at around 5.7 GHz, the proposed antenna may have potential application in wireless communication systems especially for point-to-point data transmission. It is believed that the design methodology could also be scaled to other frequency bands such as millimeter or terahertz wave.« less
Abbasi, Hamid Reza; Bolandparvaz, Shahram; Yarmohammadi, Hooman; Geramizadeh, Bita; Tanideh, Nader; Paydar, Shahram; Hosseini, Seyed Vahid
2006-10-01
Primary repair of traumatic colonic perforation is progressively gaining acceptance as the best method of management. However, when delayed, the risk of infection-related complications may increase. Here, we present a new method of repairing colon perforation in the presence of peritonitis. Acute colon injury was simulated in 22 German shepherd dogs. The dogs were randomly divided into two groups of 11 and after 24 hours they were operated on. The perforations were repaired by subserosal suture technique. In the first group (group A), ileal patch was used. In the other group (group B), the colon was closed by debridement and anastomosis. After 6 weeks, the repairs were assessed on the basis of survival, gross and histological assessments. Nine (82%) dogs in group A and six (56%) in group B survived. Ileal patch utilization significantly decreased the mortality rate (p < 0.05). The cause of death in two group A dogs and five group B dogs was peritonitis and intra-abdominal abscess formation. None of the surviving dogs showed evidence of anastomotic leakage or breakdown. Small bowel patch used in primary repair of colon injury in the presence of peritonitis may decrease the risk of postoperative infection-related complications and the mortality rate.
A Circular Microstrip Antenna Sensor for Direction Sensitive Strain Evaluation †
Herbko, Michal
2018-01-01
In this paper, a circular microstrip antenna for stress evaluation is studied. This kind of microstrip sensor can be utilized in structural health monitoring systems. Reflection coefficient S11 is measured to determine deformation/strain value. The proposed sensor is adhesively connected to the studied sample. Applied strain causes a change in patch geometry and influences current distribution both in patch and ground plane. Changing the current flow in patch influences the value of resonant frequency. In this paper, two different resonant frequencies were analysed because in each case, different current distributions in patch were obtained. The sensor was designed for operating frequency of 2.5 GHz (at fundamental mode), which results in a diameter less than 55 mm. Obtained sensitivity was up to 1 MHz/100 MPa, resolution depends on utilized vector network analyser. Moreover, the directional characteristics for both resonant frequencies were defined, studied using numerical model and verified by measurements. Thus far, microstrip antennas have been used in deformation measurement only if the direction of external force was well known. Obtained directional characteristics of the sensor allow the determination of direction and value of stress by one sensor. This method of measurement can be an alternative to the rosette strain gauge. PMID:29361697
Parameter estimation in a structural acoustic system with fully nonlinear coupling conditions
NASA Technical Reports Server (NTRS)
Banks, H. T.; Smith, Ralph C.
1994-01-01
A methodology for estimating physical parameters in a class of structural acoustic systems is presented. The general model under consideration consists of an interior cavity which is separated from an exterior noise source by an enclosing elastic structure. Piezoceramic patches are bonded to or embedded in the structure; these can be used both as actuators and sensors in applications ranging from the control of interior noise levels to the determination of structural flaws through nondestructive evaluation techniques. The presence and excitation of patches, however, changes the geometry and material properties of the structure as well as involves unknown patch parameters, thus necessitating the development of parameter estimation techniques which are applicable in this coupled setting. In developing a framework for approximation, parameter estimation and implementation, strong consideration is given to the fact that the input operator is unbonded due to the discrete nature of the patches. Moreover, the model is weakly nonlinear. As a result of the coupling mechanism between the structural vibrations and the interior acoustic dynamics. Within this context, an illustrating model is given, well-posedness and approximations results are discussed and an applicable parameter estimation methodology is presented. The scheme is then illustrated through several numerical examples with simulations modeling a variety of commonly used structural acoustic techniques for systems excitations and data collection.
DOT National Transportation Integrated Search
1979-09-01
Volume II of Theoretical Studies of Microstrip Antennas deals with the analysis and synthesis of several types of novel multi-resonant elements with emphasis on dual-frequency operation of rectangular microstrip patch antennas with or without externa...
NASA Astrophysics Data System (ADS)
Peng, Yujia; Farid Rahman, B. M.; Wang, Xuehe; Wang, Guoan
2014-05-01
Perspective magneto-dielectric materials with high permeability are potential substrates to miniaturize the patch antenna without deteriorating its performance. Besides its high permeability at high frequency, patterned Permalloy (Py) also presents tunable permeability by applying DC current. A performance enhanced miniaturized and electrically tunable patch antenna with patterned Py thin film is first presented and developed in this paper. To suppress the magnetic loss, the Py thin film layer is consisted of an array of 2 μm × 2 μm square Py patterns between the copper patch antenna and dielectric substrate. The DC current could be applied directly on Py patterns through the copper strip lines beneath the Py patterns along the length of patch antenna. The copper strip lines are specially designed with the same width of Py patterns and the thickness much less than the skin depth at the operating frequency, which can reduce their deteriorating effects to the performance of antenna. The structure of the antenna is presented and simulated with high frequency structure simulator. The results show that compared with non-magnetic antenna, the performance of Py thin film based antenna is improved with 50% bandwidth increase from 4 MHz to 8 MHz and 1.2 dB gain enhancement from 1.16 dB to 2.36 dB. The resonant frequency of the antenna could be continuously tuned from 937 MHz to 911 MHz with the permeability of Py thin film changing from 1750 to 1 900 by applying the DC current.
In vivo laser assisted end-to-end anastomosis with ICG-infused chitosan patches
NASA Astrophysics Data System (ADS)
Rossi, Francesca; Matteini, Paolo; Esposito, Giuseppe; Scerrati, Alba; Albanese, Alessio; Puca, Alfredo; Maira, Giulio; Rossi, Giacomo; Pini, Roberto
2011-07-01
Laser assisted vascular repair is a new optimized technique based on the use of ICG-infused chitosan patch to close a vessel wound, with or even without few supporting single stitches. We present an in vivo experimental study on an innovative end-to-end laser assisted vascular anastomotic (LAVA) technique, performed with the application of ICGinfused chitosan patches. The photostability and the mechanical properties of ICG-infused chitosan films were preliminary measured. The in vivo study was performed in 10 New Zealand rabbits. After anesthesia, a 3-cm segment of the right common carotid artery was exposed, thus clamped proximally and distally. The artery was then interrupted by means of a full thickness cut. Three single microsutures were used to approximate the two vessel edges. The ICG-infused chitosan patch was rolled all over the anastomotic site and welded by the use of a diode laser emitting at 810 nm and equipped with a 300 μm diameter optical fiber. Welding was obtained by delivering single laser spots to induce local patch/tissue adhesion. The result was an immediate closure of the anastomosis, with no bleeding at clamps release. Thus animals underwent different follow-up periods, in order to evaluate the welded vessels over time. At follow-up examinations, all the anastomoses were patent and no bleeding signs were documented. Samples of welded vessels underwent histological examinations. Results showed that this technique offer several advantages over conventional suturing methods: simplification of the surgical procedure, shortening of the operative time, better re-endothelization and optimal vascular healing process.
Design of an innovative magnetostrictive patch actuator
NASA Astrophysics Data System (ADS)
Cinquemani, S.; Giberti, H.
2015-04-01
Magnetostrictive actuators can be profitably used to reduce vibration in structures. However, this technology has been exploited only to develop inertial actuators, while patches actuators have not been ever used in practice. Patches actuators consist on a layer of magnetostrictive material, which has to be stuck to the surface of the vibrating structure, and on a coil surrounding the layer itself. However, the presence of the winding severely limits the use of such devices. As a matter of fact, the scientific literature reports only theoretical uses of such actuators, but, in practice it does not seem they were ever used. This paper presents an innovative solution to improve the structure of the actuator patches, allowing their use in several practical applications. The principle of operation of these devices is rather simple. The actuator patch is able to generate a local deformation of the surface of the vibrating structure so as to introduce an equivalent damping that dissipates the kinetic energy associated to the vibration. This deformation is related to the behavior of the magnetostrictive material immersed in a variable magnetic field generated by the a variable current flowing in the winding. Contrary to what suggested in the theoretical literature, the designed device has the advantage of generating the variable magnetic field no longer in close proximity of the material, but in a different area, thus allowing a better coupling. The magnetic field is then conveyed through a suitable ferromagnetic structure to the magnetostrictive material. The device has been designed and simulated through FEA. Results confirm that the new configuration can easily overcome all the limits of traditional devices.
NASA Technical Reports Server (NTRS)
Yueh, Simon; Wilson, William J.; Njoku, Eni; Dinardo, Steve; Hunter, Don; Rahmat-Samii, Yahya; Kona, Keerti S.; Manteghi, Majid
2006-01-01
The development of a compact, lightweight, dual-frequency antenna feed for future soil moisture and sea surface salinity (SSS) missions is described. The design is based on the microstrip stacked-patch array (MSPA) to be used to feed a large lightweight deployable rotating mesh antenna for spaceborne L-band (approx.1 GHz) passive and active sensing systems. The design features will also enable applications to airborne soil moisture and salinity remote sensing sensors operating on small aircrafts. This paper describes the design of stacked patch elements and 16-element array configuration. The results from the return loss, antenna pattern measurements and sky tests are also described.
NASA Technical Reports Server (NTRS)
2007-01-01
The STS-118 crew patch represents the Space Shuttle Endeavour on its mission to help complete the assembly of the International Space Station (ISS), and symbolizes the pursuit of knowledge through space exploration. The flight accomplished its ISS 13A.1 assembly tasks through a series of space walks, robotic operations, logistics transfers, and the exchange of one of the three long-duration expedition crew members. On the patch, the top of the gold astronaut symbol overlays the starboard S5 truss segment, highlighting its installation during the mission. The flame of knowledge represents the importance of education, and honors teachers and students everywhere. The seven white stars and the red maple leaf signify the American and Canadian crew members, respectively, flying aboard Endeavour.
An Enhanced Vacuum Cure Technique for On-Aircraft Repair of Carbon-Bismaleimide Composites
NASA Astrophysics Data System (ADS)
Rider, Andrew N.; Baker, Alan A.; Wang, Chun H.; Smith, Graeme
2011-06-01
Carbon/bismaleimide (BMI) composite is increasingly employed in critical load carrying aircraft structures designed to operate at temperatures approaching 180°C. The high post-cure temperature (above 220°C) required to fully react the BMI resin, however, renders existing on-aircraft prepreg or wet layup repair methods invalid. This paper presents a new on-aircraft repair technique for carbon/BMI composites. The composite prepregs are first warm-staged to improve the ability to evacuate entrapped air. Then the patch is cured in the scarf cavity using the vacuum bag technique, followed by off-aircraft post-cure. The fully cured patch then can be bonded using a structural adhesive.
NASA Technical Reports Server (NTRS)
Lauer, J. L.; Vogel, P.
1984-01-01
Deposits laid down in patches on metal strips in a high pressure/high temperature fuel system simulator operated with aerated fuel at varying flow rates were analyzed by emission FTIR in terms of functional groups. Significant differences were found in the spectra and amounts of deposits derived from fuels to which small concentrations of oxygen-, nitrogen-, or sulfur-containing heterocyclics or metal naphthenates were added. The spectra of deposits generated on strips by heating fuels and air in a closed container were very different from those of the flowing fluid deposits. One such closed-container dodecane deposit on silver gave a strong surface-enhanced Raman spectrum.
Carey, Joseph N; Sheckter, Clifford C; Watt, Andrew J; Lee, Gordon K
2013-08-01
Despite advances in nutritional supplementation, sepsis management, percutaneous drainage and surgical technique, enterocutaneous fistulae remain a considerable source of morbidity and mortality. Use of adjunctive modalities including negative pressure wound therapy and fibrin glue have been shown to improve the rapidity of fistula closure; however, the overall rate of closure remains poor. The challenge of managing chronic, high-output proximal enterocutaneous fistulae can be successfully achieved with appropriate medical management and intra-abdominal placement of pedicled rectus abdominis muscle flaps. We report two cases of recalcitrant high output enterocutaneous fistulae that were treated successfully with pedicled intra-abdominal rectus muscle flaps. Indications for pedicled intra-abdominal rectus muscle flaps include persistent patency despite a reasonable trial of non-operative intervention, failure of traditional operative interventions (serosal patch, Graham patch), and persistent electrolyte and nutritional abnormalities in the setting of a high-output fistula. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
Islam, Mohammad Tariqul; Alam, Md. Shahidul
2013-01-01
A compact planar meander-bridge high impedance electromagnetic structure (MBHIES) was designed and its bandgap characteristics, mutual coupling reduction abilities were studied and compared in detail. Several parametric analyses were performed to obtain optimized design values and the transmission responses were calculated through the suspended microstrip line and waveguide simulation methods. The achieved bandgap is 2.3 GHz (2.55–4.85 GHz) with −61 dB minimum transmission coefficient level at the center frequency of 3.6 GHz. To see the effectiveness, the proposed design was inserted between a microstrip patch antenna array which operates at 3.8 GHz and whose operating bandwidth falls within the MBHIES bandgap. The surface wave suppression phenomenon was analyzed and simulated results are verified by measuring the fabricated prototypes, both are in good agreement. The configuration reduced the mutual coupling by 20.69 dB in simulation and 19.18 dB in measurement, without affecting the radiation characteristics of the array but increasing the gain slightly. PMID:28809299
Islam, Mohammad Tariqul; Alam, Md Shahidul
2013-01-07
A compact planar meander-bridge high impedance electromagnetic structure (MBHIES) was designed and its bandgap characteristics, mutual coupling reduction abilities were studied and compared in detail. Several parametric analyses were performed to obtain optimized design values and the transmission responses were calculated through the suspended microstrip line and waveguide simulation methods. The achieved bandgap is 2.3 GHz (2.55-4.85 GHz) with -61 dB minimum transmission coefficient level at the center frequency of 3.6 GHz. To see the effectiveness, the proposed design was inserted between a microstrip patch antenna array which operates at 3.8 GHz and whose operating bandwidth falls within the MBHIES bandgap. The surface wave suppression phenomenon was analyzed and simulated results are verified by measuring the fabricated prototypes, both are in good agreement. The configuration reduced the mutual coupling by 20.69 dB in simulation and 19.18 dB in measurement, without affecting the radiation characteristics of the array but increasing the gain slightly.
Control of Fan Blade Vibrations Using Piezoelectrics and Bi-Directional Telemetry
NASA Technical Reports Server (NTRS)
Provenza, Andrew J.; Morrison, Carlos R.
2011-01-01
A novel wireless device which transfers supply power through induction to rotating operational amplifiers and transmits low voltage AC signals to and from a rotating body by way of radio telemetry has been successfully demonstrated in the NASA Glenn Research Center (GRC) Dynamic Spin Test Facility. In the demonstration described herein, a rotating operational amplifier provides controllable AC power to a piezoelectric patch epoxied to the surface of a rotating Ti plate. The amplitude and phase of the sinusoidal voltage command signal, transmitted wirelessly to the amplifier, was tuned to completely suppress the 3rd bending resonant vibration of the plate. The plate's 3rd bending resonance was excited using rotating magnetic bearing excitation while it spun at slow speed in a vacuum chamber. A second patch on the opposite side of the plate was used as a sensor. This paper discusses the characteristics of this novel device, the details of a spin test, results from a preliminary demonstration, and future plans.
Lu, Fei; Wang, Haixing; Guo, Yanjie; Tan, Qiulin; Zhang, Wendong; Xiong, Jijun
2018-01-16
A wireless and passive temperature sensor operating up to 800 °C is proposed. The sensor is based on microwave backscatter RFID (radio frequency identification) technology. A thin-film planar structure and simple working principle make the sensor easy to operate under high temperature. In this paper, the proposed high temperature sensor was designed, fabricated, and characterized. Here the 99% alumina ceramic with a dimension of 40 mm × 40 mm × 1 mm was prepared in micromechanics for fabrication of the sensor substrate. The metallization of the Au slot patch was realized in magnetron sputtering with a slot width of 2 mm and a slot length of 32 mm. The measured resonant frequency of the sensor at 25 °C is 2.31 GHz. It was concluded that the resonant frequency decreases with the increase in the temperature in range of 25-800 °C. It was shown that the average sensor sensitivity is 101.94 kHz/°C.
Cummins, Sharon; Zhu, Shu-Hong; Gamst, Anthony; Kirby, Carrie; Brandstein, Kendra; Klonoff-Cohen, Hillary; Chaplin, Edward; Morris, Timothy; Seymann, Gregory; Lee, Joshua
2012-08-01
Hospitalized smokers often quit smoking, voluntarily or involuntarily; most relapse soon after discharge. Extended follow-up counseling can help prevent relapse. However, it is difficult for hospitals to provide follow-up and smokers rarely leave the hospital with quitting aids (for example, nicotine patches). This study aims to test a practical model in which hospitals work with a state cessation quitline. Hospital staff briefly intervene with smokers at bedside and refer them to the quitline. Depending on assigned condition, smokers may receive nicotine patches at discharge or extended quitline telephone counseling post-discharge. This project establishes a practical model that lends itself to broader dissemination, while testing the effectiveness of the interventions in a rigorous randomized trial. This randomized clinical trial (N = 1,640) tests the effect of two interventions on long-term quit rates of hospitalized smokers in a 2 x 2 factorial design. The interventions are (1) nicotine patches (eight-week, step down program) dispensed at discharge and (2) proactive telephone counseling provided by the state quitline after discharge. Subjects are randomly assigned into: usual care, nicotine patches, telephone counseling, or both patches and counseling. It is hypothesized that patches and counseling have independent effects and their combined effect is greater than either alone. The primary outcome measure is thirty-day abstinence at six months; a secondary outcome is biochemically validated smoking status. Cost-effectiveness analysis is conducted to compare each intervention condition (patch alone, counseling alone, and combined interventions) against the usual care condition. Further, this study examines whether smokers' medical diagnosis is a moderator of treatment effect. Generalized linear (binomial) mixed models will be used to study the effect of treatment on abstinence rates. Clustering is accounted for with hospital-specific random effects. If this model is effective, quitlines across the U.S. could work with interested hospitals to set up similar systems. Hospital accreditation standards related to tobacco cessation performance measures require follow-up after discharge and provide additional incentive for hospitals to work with quitlines. The ubiquity of quitlines, combined with the consistency of quitline counseling delivery as centralized state operations, make this partnership attractive. Smoking cessation in hospitalized smokers NCT01289275. Date of registration February 1, 2011; date of first patient August 3, 2011.
Zhang, Yuanke; Lu, Hongbing; Rong, Junyan; Meng, Jing; Shang, Junliang; Ren, Pinghong; Zhang, Junying
2017-09-01
Low-dose CT (LDCT) technique can reduce the x-ray radiation exposure to patients at the cost of degraded images with severe noise and artifacts. Non-local means (NLM) filtering has shown its potential in improving LDCT image quality. However, currently most NLM-based approaches employ a weighted average operation directly on all neighbor pixels with a fixed filtering parameter throughout the NLM filtering process, ignoring the non-stationary noise nature of LDCT images. In this paper, an adaptive NLM filtering scheme on local principle neighborhoods (PC-NLM) is proposed for structure-preserving noise/artifacts reduction in LDCT images. Instead of using neighboring patches directly, in the PC-NLM scheme, the principle component analysis (PCA) is first applied on local neighboring patches of the target patch to decompose the local patches into uncorrelated principle components (PCs), then a NLM filtering is used to regularize each PC of the target patch and finally the regularized components is transformed to get the target patch in image domain. Especially, in the NLM scheme, the filtering parameter is estimated adaptively from local noise level of the neighborhood as well as the signal-to-noise ratio (SNR) of the corresponding PC, which guarantees a "weaker" NLM filtering on PCs with higher SNR and a "stronger" filtering on PCs with lower SNR. The PC-NLM procedure is iteratively performed several times for better removal of the noise and artifacts, and an adaptive iteration strategy is developed to reduce the computational load by determining whether a patch should be processed or not in next round of the PC-NLM filtering. The effectiveness of the presented PC-NLM algorithm is validated by experimental phantom studies and clinical studies. The results show that it can achieve promising gain over some state-of-the-art methods in terms of artifact suppression and structure preservation. With the use of PCA on local neighborhoods to extract principal structural components, as well as adaptive NLM filtering on PCs of the target patch using filtering parameter estimated based on the local noise level and corresponding SNR, the proposed PC-NLM method shows its efficacy in preserving fine anatomical structures and suppressing noise/artifacts in LDCT images. © 2017 American Association of Physicists in Medicine.
NASA Astrophysics Data System (ADS)
Ko, Seungbin; Song, Simon; Kim, Doosang
2016-11-01
It is remained unknown that the flow characteristics changes between pre- and post-operative severe carotid artery stenosis could affect the long-term patency or failure. However, in-vivo clinical experiments to uncover the flow details are far from bed-side due to limited measurement resolutions, blurring artifact, etc. We studied detailed flow characteristics of more than 75% severe carotid artery stenosis before and after surgical treatments. Real-size flow phantoms for 10 patients, who underwent carotid endarterectomy with patch/no patch closure, were prepared by using a 3D rapid-prototype machine from CT scanned images. The working fluid is a glycerin aqueous solution, and patient-specific pulsatile flows were applied to the phantoms, based on ultrasonic flow rate measurements. The flows were visualized with magnetic resonance velocimetry (MRV). The detailed flow characteristics are presented for both pre- and post-operative carotid arteries along with visualization data of 3 dimensional, 3 component velocity fields. This work was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIP) (No. 2016R1A2B3009541).
Kazahari, Nobuko
2014-04-01
Animals have been assumed to employ an optimal foraging strategy (e.g., rate-maximizing strategy). In patchy food environments, intake rate within patches is positively correlated with patch quality, and declines as patches are depleted through consumption. This causes patch-leaving and determines patch residence time. In group-foraging situations, patch residence times are also affected by patch sharing. Optimal patch models for groups predict that patch residence times decrease as the number of co-feeding animals increases because of accelerated patch depletion. However, group members often depart patches without patch depletion, and their patch residence time deviates from patch models. It has been pointed out that patch residence time is also influenced by maintaining social proximity with others among group-living animals. In this study, the effects of maintaining social cohesion and that of rate-maximizing strategy on patch residence time were examined in Japanese macaques (Macaca fuscata). I hypothesized that foragers give up patches to remain in the proximity of their troop members. On the other hand, foragers may stay for a relatively long period when they do not have to abandon patches to follow the troop. In this study, intake rate and foraging effort (i.e., movement) did not change during patch residency. Macaques maintained their intake rate with only a little foraging effort. Therefore, the patches were assumed to be undepleted during patch residency. Further, patch residence time was affected by patch-leaving to maintain social proximity, but not by the intake rate. Macaques tended to stay in patches for short periods when they needed to give up patches for social proximity, and remained for long periods when they did not need to leave to keep social proximity. Patch-leaving and patch residence time that prioritize the maintenance of social cohesion may be a behavioral pattern in group-living primates.
2012-08-16
This patch represents the essential elements associated with pressurized Earth science research aboard the International Space Station. At the top of the patch Klingon script spells out the acronym WORF making reference to the famed Star Trek character of the same name. In doing so it attests to the foresight, honor, integrity, and persistence of all those who made the WORF possible. To the right of the Klingon script is a single four pointed star in the form of a cross to honor the late Dr. Jack Estes and Dr. Dave Amsbury, the individuals most responsible for seeing to it that an optical quality, Earth science research window was added to the United States laboratory module, Destiny. The "flying eyeball" represents the ability of the ISS to allow scientists and astronauts to make and record continuous observations of natural and manmade processes on the surface of the Earth. The Destiny laboratory is depicted on the right of the patch above the Flag of the United States of America and highlights the position of the nadir looking, optical quality, science window in the module. The light emanating from the window from the lighted interior of the module appropriately illuminates the National Ensign for display during both day and night time. In the center of the patch, below the flying eyeball is a graphic representation of the WORF rack. A science instrument is mounted on the WORF payload shelf and is recording data of the Earth's surface through the nadir looking, science window over which the WORF rack is mounted. An astronaut represented by Mario Runco Jr., a designer, developer, and manager of the WORF and depicted as Star Trek's Mr. Spock, is to the left of the WORF rack and is shown in his flight suit with his STS-44 mission patch operating an imaging instrument, emphasizing the importance of astronaut participation to achieve the maximum scientific return from orbital research.
NASA Astrophysics Data System (ADS)
Mora, Carla; Jiménez, Juan Javier; Pina, Pedro; Catalão, João; Vieira, Gonçalo
2017-01-01
The mountainous and ice-free terrains of the maritime Antarctic generate complex mosaics of snow patches, ranging from tens to hundreds of metres. These can only be accurately mapped using high-resolution remote sensing. In this paper we evaluate the application of radar scenes from TerraSAR-X in High Resolution SpotLight mode for mapping snow patches at a test area on Fildes Peninsula (King George Island, South Shetlands). Snow-patch mapping and characterization of snow stratigraphy were conducted at the time of image acquisition on 12 and 13 January 2012. Snow was wet in all studied snow patches, with coarse-grain and rounded crystals showing advanced melting and with frequent ice layers in the snow pack. Two TerraSAR-X scenes in HH and VV polarization modes were analysed, with the former showing the best results when discriminating between wet snow, lake water and bare soil. However, significant overlap in the backscattering signal was found. Average wet-snow backscattering was -18.0 dB in HH mode, with water showing -21.1 dB and bare soil showing -11.9 dB. Single-band pixel-based and object-oriented image classification methods were used to assess the classification potential of TerraSAR-X SpotLight imagery. The best results were obtained with an object-oriented approach using a watershed segmentation with a support vector machine (SVM) classifier, with an overall accuracy of 92 % and Kappa of 0.88. The main limitation was the west to north-west facing snow patches, which showed significant error, an issue related to artefacts from the geometry of satellite imagery acquisition. The results show that TerraSAR-X in SpotLight mode provides high-quality imagery for mapping wet snow and snowmelt in the maritime Antarctic. The classification procedure that we propose is a simple method and a first step to an implementation in operational mode if a good digital elevation model is available.
NASA Astrophysics Data System (ADS)
Rossi, Francesca; Matteini, Paolo; Menabuoni, Luca; Lenzetti, Ivo; Pini, Roberto
2011-03-01
The common procedures used to seal the scleral or conjunctival injuries are based on the traditional suturing techniques, that may induce foreign body reaction during the follow up, with subsequent inflammation and distress for the patient. In this work we present an experimental study on the laser welding of biocompatible patches onto ocular tissues, for the closure of surgical or trauma wounds. The study was performed ex vivo in animal models (porcine eyes). A penetrating perforation of the ocular tissue was performed with a surgical knife. The wound walls were approximated, and a biocompatible patch was put onto the outer surface of the tissue, in order to completely cover the wound as a plaster. The patches were prepared with a biocompatible and biodegradable polymer, showing high mechanical strength, good elasticity, high permeability for vapour and gases and rather low biodegradation. During preparation, Indocyanine Green (ICG) was included in the biopolymeric matrix, so that the films presented high absorption at 810 nm. Effective adhesion of the membranes to the ocular tissues was obtained by using diode laser light emitted from an 810 nm diode laser and delivered by means of a 300 μm core diameter optical fiber, to produce spots of local film/tissue adhesion, due to the photothermal effect at the interface. The result is an immediate closure of the wound, thus reducing post-operative complications due to inflammation.
Scrapping Patched Computer Systems: Integrated Data Processing for Information Management.
ERIC Educational Resources Information Center
Martinson, Linda
1991-01-01
Colleges and universities must find a way to streamline and integrate information management processes across the organization. The Georgia Institute of Technology responded to an acute problem of dissimilar operating systems with a campus-wide integrated administrative system using a machine independent relational database management system. (MSE)
Liu, Xiaolin; Yang, Yunlong; Li, Yan; Niu, Xin; Zhao, Bizeng; Wang, Yang; Bao, Chunyan; Xie, Zongping; Lin, Qiuning; Zhu, Linyong
2017-03-30
The regeneration of articular cartilage, which scarcely shows innate self-healing ability, is a great challenge in clinical treatment. Stem cell-derived exosomes (SC-Exos), an important type of extracellular nanovesicle, exhibit great potential for cartilage regeneration to replace stem cell-based therapy. Cartilage regeneration often takes a relatively long time and there is currently no effective administration method to durably retain exosomes at cartilage defect sites to effectively exert their reparative effect. Therefore, in this study, we exploited a photoinduced imine crosslinking hydrogel glue, which presents excellent operation ability, biocompatibility and most importantly, cartilage-integration, as an exosome scaffold to prepare an acellular tissue patch (EHG) for cartilage regeneration. It was found that EHG can retain SC-Exos and positively regulate both chondrocytes and hBMSCs in vitro. Furthermore, EHG can integrate with native cartilage matrix and promote cell deposition at cartilage defect sites, finally resulting in the promotion of cartilage defect repair. The EHG tissue patch therefore provides a novel, cell-free scaffold material for wound repair.
Wang, Guangfu; Wyskiel, Daniel R; Yang, Weiguo; Wang, Yiqing; Milbern, Lana C; Lalanne, Txomin; Jiang, Xiaolong; Shen, Ying; Sun, Qian-Quan; Zhu, J Julius
2015-01-01
Deciphering neuronal circuitry is central to understanding brain function and dysfunction, yet it remains a daunting task. To facilitate the dissection of neuronal circuits, a process requiring functional analysis of synaptic connections and morphological identification of interconnected neurons, we present here a method for stable simultaneous octuple patch-clamp recordings. This method allows physiological analysis of synaptic interconnections among 4–8 simultaneously recorded neurons and/or 10–30 sequentially recorded neurons, and it allows anatomical identification of >85% of recorded interneurons and >99% of recorded principal neurons. We describe how to apply the method to rodent tissue slices; however, it can be used on other model organisms. We also describe the latest refinements and optimizations of mechanics, electronics, optics and software programs that are central to the realization of a combined single- and two-photon microscopy–based, optogenetics- and imaging-assisted, stable, simultaneous quadruple–viguple patch-clamp recording system. Setting up the system, from the beginning of instrument assembly and software installation to full operation, can be completed in 3–4 d. PMID:25654757
Abiotic controls of emergent macrophyte density in a bedrock channel - The Cahaba River, AL (USA)
NASA Astrophysics Data System (ADS)
Vaughn, Ryan S.; Davis, Lisa
2015-10-01
Research examining bedrock channels is growing. Despite this, biotic-abiotic interactions remain a topic mostly addressed in alluvial systems. This research identified hydrogeomorphic factors operating at the patch-scale (100-102 m) in bedrock shoals of the Cahaba River (AL) that help determine the distribution of the emergent aquatic macrophyte, Justicia americana. Macrophyte patch density (number of stems/m2) and percent bedrock void surface area (rock surface area/m2 occupied by joints, fractures, and potholes) were measured (n = 24 within two bedrock shoals) using stem counts and underwater photography, respectively. One-dimensional hydrologic modeling (HEC-RAS 4.1.0) was completed for a section within a shoal to examine velocity and channel depth as controlling variables for macrophyte patch density. Results from binary logistic regression analysis identified depth and velocity as good predictors of the presence or absence of Justicia americana within shoal structures (depth p = 0.001, velocity p = 0.007), which is a similar finding to previous research conducted in alluvial systems. Correlation analysis between bedrock surface void area and stem density demonstrated a statistically significant positive correlation (r = 0.665, p = 0.01), elucidating a link between abiotic-biotic processes that may well be unique to bedrock channels. These results suggest that the amount of void space present in bedrock surfaces, in addition to localized depth and velocity, helps control macrophyte patch density in bedrock shoal complexes. The utility of geomorphology in explaining patch-scale habitat heterogeneity in this study highlights geomorphology's potential to help understand macrophyte habitat heterogeneity at the reach scale, while also demonstrating its promise for mapping and understanding habitat heterogeneity at the system scale.
Batzli, George O
2016-11-01
Increased habitat fragmentation leads to smaller size of habitat patches and to greater distance between patches. The ROMPA hypothesis (ratio of optimal to marginal patch area) uniquely links vole population fluctuations to the composition of the landscape. It states that as ROMPA decreases (fragmentation increases), vole population fluctuations will increase (including the tendency to display multi-annual cycles in abundance) because decreased proportions of optimal habitat result in greater population declines and longer recovery time after a harsh season. To date, only comparative observations in the field have supported the hypothesis. This paper reports the results of the first experimental test. I used prairie voles, Microtus ochrogaster, and mowed grassland to create model landscapes with 3 levels of ROMPA (high with 25% mowed, medium with 50% mowed and low with 75% mowed). As ROMPA decreased, distances between patches of favorable habitat (high cover) increased owing to a greater proportion of unfavorable (mowed) habitat. Results from the first year with intensive live trapping indicated that the preconditions for operation of the hypothesis existed (inversely density dependent emigration and, as ROMPA decreased, increased per capita mortality and decreased per capita movement between optimal patches). Nevertheless, contrary to the prediction of the hypothesis that populations in landscapes with high ROMPA should have the lowest variability, 5 years of trapping indicated that variability was lowest with medium ROMPA. The design of field experiments may never be perfect, but these results indicate that the ROMPA hypothesis needs further rigorous testing. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.
The study of microstrip antenna arrays and related problems
NASA Technical Reports Server (NTRS)
Lo, Y. T.
1984-01-01
The physical layout of the array elements and the proximity of the microstrip feed network makes the input impedance and radiation pattern values dependent upon the effects of mutual coupling, feedline discontinuities and feed point location. The extent of these dependences was assessed and a number of single patch and module structures were constructed and measured at an operating frequency of approximately 4.0 GHz. The empirical results were compared with the ones which were theoretically predicted by the cavity model of thin microstrip antennas. Each element was modelled as an independent radiating patch and each microstrip feedline as an independent, quasi-TEM transmission line. The effects of the feedline discontinuities are approximated by lumped L-C circuit models.
Multiscale assessment of landscape structure in heterogeneous forested area
NASA Astrophysics Data System (ADS)
Simoniello, T.; Pignatti, S.; Carone, M. T.; Fusilli, L.; Lanfredi, M.; Coppola, R.; Santini, F.
2010-05-01
The characterization of landscape structure in space or time is fundamental to infer ecological processes (Ingegnoli, 2002). Landscape pattern arrangements strongly influence forest ecological functioning and biodiversity, as an example landscape fragmentation can induce habitat degradation reducing forest species populations or limiting their recolonization. Such arrangements are spatially correlated and scale-dependent, therefore they have distinctive operational-scales at which they can be best characterized (Wu, 2004). In addition, the detail of the land cover classification can have substantial influences on resulting pattern quantification (Greenberg et al.2001). In order to evaluate the influence of the observational scales and labelling details, we investigated a forested area (Pollino National Park; southern Italy) by analyzing the patch arrangement derived from three remote sensing sensors having different spectral and spatial resolutions. In particular, we elaborated data from the hyperspectral MIVIS (102 bands; ~7m) and Hyperion (220 bands; 30m), and the multispectral Landsat-TM (7 bands; 30m). Moreover, to assess the landscape evolution we investigated the hierarchical structure of the study area (landscape, class, patch) by elaborating two Landsat-TM acquired in 1987 and 1998. Preprocessed data were classified by adopting a supervised procedure based on the Minimum Distance classifier. The obtained labelling correspond to Corine level 5 for the high resolution MIVIS data, to Corine level 4 for Hyperion and to an intermediate level 4-3 for TM data. The analysis was performed by taking into account patch density, diversity and evenness at landscape level; mean patch size and interdispersion at class level; patch structure and perimeter regularity at patch level. The three sensors described a landscape with a quite high level of richness and distribution. The high spectral and spatial resolution of MIVIS data provided the highest diversity level (SHDI = 2.05), even if the results obtained for TM were not so different (1.93), Hyperion showed the lowest value (1.79). The obtained evenness index was similar for all the landscapes (~ 0.72). At class level, the interdispersion increases as the spatial and spectral resolution power decrease. Due to the low labelling detail, TM classes represent an aggregation of MIVIS and Hyperion classes; therefore they result larger and more diffused over the territory favouring higher interspersion values in the computation. The investigation of the patch structure highlighted the highest MIVIS capability in describing the patch articulation; Hyperion and TM showed quite similar situation. The historical analysis based on TM imagery showed a fragmentation process for some forested patches (mainly beeches): an increase of structure complexity (higher FRACT) is coupled with a higher patch number and an extension reduction. On the whole, the obtained results showed that the multispectral Landsat-TM images represent a good data source for supporting studies on landscape structure of forested areas and that for analyzing the articulation of particular species the high spectral resolution needs to be coupled with a high spatial resolution, i.e. Hyperion sampling is not adequate for such a purpose.
Habitat quality and geometry affect patch occupancy of two Orthopteran species.
Pasinelli, Gilberto; Meichtry-Stier, Kim; Birrer, Simon; Baur, Bruno; Duss, Martin
2013-01-01
Impacts of habitat loss and fragmentation on distribution and population size of many taxa are well established. In contrast, less is known about the role of within-patch habitat quality for the spatial dynamics of species, even though within-patch habitat quality may substantially influence the dynamics of population networks. We studied occurrence patterns of two Orthopteran species in relation to size, isolation and quality of habitat patches in an intensively managed agricultural landscape (16.65 km(2)) in the Swiss lowland. Occurrence of field crickets (Gryllus campestris) was positively related to patch size and negatively to the distance to the nearest occupied patch, two measures of patch geometry. Moreover, field crickets were more likely to occur in extensively managed meadows, meadows used at low intensity and meadows dominated by Poa pratensis, three measures of patch quality. Occurrence of the large gold grasshopper (Chrysochraon dispar) was negatively related to two measures of patch geometry, distance to the nearest occupied patch and perimeter index (ratio of perimeter length to patch area). Further, large gold grasshoppers were more likely to occupy patches close to water and patches with vegetation left uncut over winter, two measures of patch quality. Finally, examination of patch occupancy dynamics of field crickets revealed that patches colonized in 2009 and patches occupied in both 2005 and 2009 were larger, better connected and of other quality than patches remaining unoccupied and patches from which the species disappeared. The strong relationships between Orthopteran occurrence and aspects of patch geometry found in this study support the "area-and-isolation paradigm". Additionally, our study reveals the importance of patch quality for occurrence patterns of both species, and for patch occupancy dynamics in the field cricket. An increased understanding of patch occupancy patterns may be gained if inference is based on variables related to both habitat geometry and quality.
Kaunitz, Andrew M; Portman, David; Westhoff, Carolyn L; Mishell, Daniel R; Archer, David F; Foegh, Marie
2015-03-01
To evaluate skin irritation and patch adhesiveness of a new weekly low-dose levonorgestrel (LNG) and ethinyl estradiol (EE) contraceptive patch (LNG/EE patch). This analysis was part of an open-label, parallel-group, multicenter, phase 3 study that randomized healthy women to the LNG/EE patch (one patch weekly for three consecutive weeks, followed by a patch-free week for 13 cycles) or to an oral contraceptive for six cycles followed by seven LNG/EE patch cycles. Participants selected patch application sites of abdomen, buttock or upper torso. Investigators rated patch adhesiveness and skin irritation using standardized scales. Participants rated skin irritation and itching daily using standardized scales and recorded patch fall-off on daily diary cards. A total of 32,508 patches were applied (n=1273). At the five clinic visits in which investigators rated the patches, they rated adhesiveness=0 (no lift) for ≥84% of participants and skin irritation=absent/mild for 97% of patches. Participants reported that 2-3.7% of patches fell off and rated skin irritation as absent or mild for 92- 95% of patches, according to site. Investigator- and participant-rated assessments of LNG/EE patch adhesiveness and irritation demonstrated a low incidence of patch detachment, skin irritation and pruritus. This secondary analysis of a phase 3 clinical trial of a new weekly low-dose LNG and EE contraceptive patch, which used assessment by both investigators and participants, observed a low incidence of skin irritation, pruritus and patch detachment. Copyright © 2015 Elsevier Inc. All rights reserved.
Mating success of males with and without wing patch in Drosophila biarmipes.
Hegde, S N; Chethan, B K; Krishna, M S
2005-10-01
Some males of D. biarmipes--synonym of D. rajasekari and D. raychaudhuri have a black patch on the wing. The patch extends from the apical margin of wing to the third longitudinal vein. Field and laboratory studies have been carried out in D. biarmipes to study role of male's wing patch in mating success. The field study shows that nature favors D. biarmipes males with patch. Although males without patch mated, males with patch have higher mating success suggesting the role of wing patch during courtship. Further, among mating males, males with patch had longer wings than males without patch. During courtship, males with patch oriented and mated faster; performed courtship acts such as tapping, scissoring, vibration, licking and twist dance more times than males without patch in both competitive and non-competitive situations. The results indicate that there is a casual relationship between the presence of wing patch, mating speed and success. Also there is a correlation between presence of wing patch, size of the flies and mating success.
Scale dependent drivers of wild bee diversity in tropical heterogeneous agricultural landscapes.
Basu, Parthiba; Parui, Arpan Kumar; Chatterjee, Soumik; Dutta, Aditi; Chakraborty, Pushan; Roberts, Stuart; Smith, Barbara
2016-10-01
Factors associated with agricultural intensification, for example, loss of seminatural vegetation and pesticide use has been shown to adversely affect the bee community. These factors may impact the bee community differently at different landscape scales. The scale dependency is expected to be more pronounced in heterogeneous landscapes. However, the scale-dependent response of the bee community to drivers of its decline is relatively understudied, especially in the tropics where the agricultural landscape is often heterogeneous. This study looked at effects of agricultural intensification on bee diversity at patch and landscape scales in a tropical agricultural landscape. Wild bees were sampled using 12 permanent pan trap stations. Patch and landscape characteristics were measured within a 100 m (patch scale) and a 500 m (landscape scale) radius of pan trap stations. Information on pesticide input was obtained from farmer surveys. Data on vegetation cover, productivity, and percentage of agricultural and fallow land (FL) were collected using satellite imagery. Intensive areas in a bee-site network were less specialized in terms of resources to attract rare bee species while the less intensive areas, which supported more rare species, were more vulnerable to disturbance. A combination of patch quality and diversity as well as pesticide use regulates species diversity at the landscape scale (500 m), whereas pesticide quantity drove diversity at the patch scale (100 m). At the landscape scale, specialization of each site in terms of resources for bees increased with increasing patch diversity and FL while at the patch scale specialization declined with increased pesticide use. Bee functional groups responded differentially to landscape characteristics as well as pesticide use. Wood nesting bees were negatively affected by the number of pesticides used but other bee functional groups were not sensitive to pesticides. Synthesis and Applications : Different factors affect wild bee diversity at the scale of landscape and patch in heterogeneous tropical agricultural systems. The differential response of bee functional groups to agricultural intensification underpins the need for guild-specific management strategies for wild bee conservation. Less intensively farmed areas support more rare species and are vulnerable to disturbance; consequently, these areas should be prioritized for conservation to maintain heterogeneity in the landscape. It is important to conserve and restore seminatural habitats to maintain complexity in the landscapes through participatory processes and to regulate synthetic chemical pesticides in farm operations to conserve the species and functional diversity of wild bees.
Ardelt, M; Dittmar, Y; Scheuerlein, H; Bärthel, E; Settmacher, U
2014-01-01
We report the case of a 39-year-old woman with ileus resulting from a small bowel incarceration underneath the right common iliac artery. The patient had a history of a radical trachelectomy with laparoscopic pelvic lymphadenectomy ("Dargent's operation") for cervical carcinoma. After dissection of the iliac vessels, a small bowel loop could slide underneath the common iliac artery. The hernia was closed by gluing a collagen patch over the right common iliac artery onto the retroperitoneal cavity. To our knowledge, such a case has not previously been reported in the medical literature.
The C-patch - A small microstrip element
NASA Astrophysics Data System (ADS)
Kossiavas, G.; Papiernik, A.; Boisset, J. P.; Sauvan, M.
1989-02-01
A radiating element operating in the UHF and L-bands is presented. The element has dimensions smaller than those of conventional square or circular elements. For this type of antenna, good matching is obtained with a coaxial feed, and the omnidirectional radiation pattern is achieved using linear polarization. The bandwidth, however, remains somewhat narrow.
Uneven-aged management of northern hardwoods in New England
William B. Leak; Stanley M. Filip
1975-01-01
Three main aspects of uneven-aged management in northern hardwoods are discussed: (1) choice of cutting method, including selection, group selection, and patch selection; (2) control of yields, which involves the establishment of structural goals, the control of marking operations, and the prediction of allowable harvest; and (3) the transportation or removal of...
Early closure of postinfarction ventricular septal defects.
Martinelli, Luigi; Dottori, Vincenzo; Caputo, Enrico; Graffigna, Angelo; Pederzolli, Carlo
2003-05-01
According to the guidelines of the American College of Cardiology/American Heart Association early closure of postinfarction septal defects is now a class I indication although it still carries a relevant morbidity and mortality. The operative risk is related both to the critical hemodynamic conditions of the patient and to the technical difficulties posed by the friable tissue of the infarcted area. The most recent techniques involving the use of pericardial patches reinforced by acrylic glue have significantly reduced the hospital mortality. The aim of this study was to discuss the reliability of an aggressive, tissue-sparing surgical approach to this complication. We present a consecutive series of 12 patients operated upon between January 1998 and October 2001 within 12 hours of the onset of clinical evidence of postinfarction septal rupture. Repair was achieved with minimal septal debridement and the use of a large pericardial patch reinforced by a biological glue. Three cases of dehiscence required early reoperation with no hospital mortality. This procedure is technically feasible and allows early aggressive treatment of postinfarction septal rupture with satisfactory results.
A multichannel block-matching denoising algorithm for spectral photon-counting CT images.
Harrison, Adam P; Xu, Ziyue; Pourmorteza, Amir; Bluemke, David A; Mollura, Daniel J
2017-06-01
We present a denoising algorithm designed for a whole-body prototype photon-counting computed tomography (PCCT) scanner with up to 4 energy thresholds and associated energy-binned images. Spectral PCCT images can exhibit low signal to noise ratios (SNRs) due to the limited photon counts in each simultaneously-acquired energy bin. To help address this, our denoising method exploits the correlation and exact alignment between energy bins, adapting the highly-effective block-matching 3D (BM3D) denoising algorithm for PCCT. The original single-channel BM3D algorithm operates patch-by-patch. For each small patch in the image, a patch grouping action collects similar patches from the rest of the image, which are then collaboratively filtered together. The resulting performance hinges on accurate patch grouping. Our improved multi-channel version, called BM3D_PCCT, incorporates two improvements. First, BM3D_PCCT uses a more accurate shared patch grouping based on the image reconstructed from photons detected in all 4 energy bins. Second, BM3D_PCCT performs a cross-channel decorrelation, adding a further dimension to the collaborative filtering process. These two improvements produce a more effective algorithm for PCCT denoising. Preliminary results compare BM3D_PCCT against BM3D_Naive, which denoises each energy bin independently. Experiments use a three-contrast PCCT image of a canine abdomen. Within five regions of interest, selected from paraspinal muscle, liver, and visceral fat, BM3D_PCCT reduces the noise standard deviation by 65.0%, compared to 40.4% for BM3D_Naive. Attenuation values of the contrast agents in calibration vials also cluster much tighter to their respective lines of best fit. Mean angular differences (in degrees) for the original, BM3D_Naive, and BM3D_PCCT images, respectively, were 15.61, 7.34, and 4.45 (iodine); 12.17, 7.17, and 4.39 (galodinium); and 12.86, 6.33, and 3.96 (bismuth). We outline a multi-channel denoising algorithm tailored for spectral PCCT images, demonstrating improved performance over an independent, yet state-of-the-art, single-channel approach. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.
Pretreatment of pericardial patches with antibiotics does not alter patch healing in vivo.
Bai, Hualong; Kuwahara, Go; Wang, Mo; Brownson, Kirstyn E; Foster, Trenton R; Yamamoto, Kota; Xing, Ying; Dardik, Alan
2016-04-01
Pretreatment with antibiotics is commonly performed before surgical implantation of prosthetic materials. We previously showed that pericardial patches are infiltrated by macrophages and arterial stem cells after implantation into an artery. We hypothesized that antibiotic pretreatment would diminish the number of cells infiltrating into the patch, potentially affecting early neointimal formation. Bovine pericardial patches were pretreated with saline, bacitracin (500 U/mL), or cephalexin (10 mg/mL) for 30 minutes before implantation into the Wistar rat infrarenal aorta. Patches were retrieved on day 7 or day 30 and analyzed for histology and cell infiltration. Markers of proliferation, apoptosis, vascular cell identity, and M1 and M2 macrophage subtypes were examined using immunofluorescence and immunohistochemistry. Extracted proteins were analyzed by Western blot. At day 7, pericardial patches pretreated with bacitracin or cephalexin showed similar amounts of neointimal thickening (P = .55) and cellular infiltration (P = .42) compared with control patches. Patches pretreated with antibiotics showed similar proliferation (P = .09) and apoptosis (P = .84) as control patches. The cell composition of the neointima in pretreated patches was similar to control patches, with a thin endothelial layer overlying a thin layer of smooth muscle cells (P = .45), and containing similar numbers of CD34-positive (P = .26) and vascular endothelial growth factor receptor 2-positive (P = .31) cells. Interestingly, within the body of the patch, there were fewer macrophages (P = .0003) and a trend towards fewer endothelial progenitor cells (P = .051). No M1 macrophages were found in or around any of the patches. M2 macrophages were present around the patches, and there was no difference in numbers of M2 macrophages surrounding control patches and patches pretreated with antibiotics (P = .24). There was no difference in neointimal thickness at day 30 between control patches and patches pretreated with antibiotics (P = .52). Pretreatment of bovine pericardial patches with the antibiotics bacitracin or cephalexin has no detrimental effect on early patch healing, with similar neointimal thickness, cellular infiltration, and numbers of M2 macrophages compared with control patches. These results suggest that the host vessel response to patch angioplasty using pericardial patches is adaptive remodeling (eg, arterial healing). Published by Elsevier Inc.
Donner, Deahn M.; Ribic, Christine; Probst, John R.
2010-01-01
Habitat colonization and abandonment affects the distribution of a species in space and time, ultimately influencing the duration of time habitat is used and the total area of habitat occupied in any given year. Both aspects have important implications to long-term conservation planning. The importance of patch isolation and area to colonization–extinction events is well studied, but little information exists on how changing regional landscape structure and population dynamics influences the variability in the timing of patch colonization and abandonment events. We used 26 years of Kirtland’s Warbler (Dendroica kirtlandii) population data taken during a habitat restoration program (1979–2004) across its historical breeding range to examine the influence of patch attributes and temporal large-scale processes, specifically the rate of habitat turnover and fraction of occupied patches, on the year-to-year timing of patch colonization and abandonment since patch origin. We found the timing of patch colonization and abandonment was influenced by patch and large-scale regional factors. In this system, larger patches were typically colonized earlier (i.e., at a younger age) and abandoned later than smaller patches. Isolated patches (i.e., patches farther from another occupied patch) were generally colonized later and abandoned earlier. Patch habitat type affected colonization and abandonment; colonization occurred at similar patch ages between plantation and wildfire areas (9 and 8.5 years, respectively), but plantations were abandoned at earlier ages (13.9 years) than wildfire areas (16.4 years) resulting in shorter use. As the fraction of occupied patches increased, patches were colonized and abandoned at earlier ages. Patches were abandoned at older ages when the influx of new habitat patches was at low and high rates. Our results provide empirical support for the temporal influence of patch dynamics (i.e., patch destruction, creation, and succession) on local colonization and extinction processes that help explain large-scale patterns of habitat occupancy. Results highlight the need for practitioners to consider the timing of habitat restoration as well as total amount and spatial arrangement of habitat to sustain populations.
Ethinyl Estradiol and Norelgestromin Transdermal Patch
... the skin. One patch is applied once a week for 3 weeks, followed by a patch-free week. Follow the directions on your prescription label carefully, ... new patch on the same day of the week (the Patch Change Day). Apply a new patch ...
Jiang, Yuan-Hong
2017-01-01
Purpose Stress urinary incontinence (SUI) in men is a complication secondary to prostatectomy or resulting from neurological lesions. This study presents our experiences with male suburethral slings over the past decade. Methods In this study, we considered patients who presented with SUI and were diagnosed with an intrinsic sphincteric deficiency due to postprostatectomy incontinence (PPI) or other causes (non-PPI). Patients who underwent the suburethral sling procedure using a polypropylene mesh and a cardiovascular patch were retrospectively included. An urodynamic study was performed before and after the operation. Global response assessment (GRA) and SUI grading were used for surgical outcome. The revision rate and the infection rate were also evaluated. Results A total 31 patients were enrolled in this study; the mean patient age was 59.5±18.9 years, and the mean follow-up period was 36.9±29.4 months. Fourteen patients comprised the non-PPI group and 17 were in the PPI group. The preoperative SUI of all patients were categorized as a moderate to severe problem according to the SUI grade, with a mean score of 2.32±0.48 before the operation and 0.48±0.57 after the operation. With a mean score of 2.35±0.71, GRA showed that the patients were satisfied with the treatment. After the sling procedure, 4 patients (13%) reported a mild improvement, 12 (38.7%) a moderate improvement, while 15 (48.4%) reported an excellent improvement. Six patients (19.4%), including 5 from the non-PPI group (35.7%) and 1 (5.9%) from the PPI group (P=0.037), underwent sling removal because of infection. Conclusions The male suburethral sling procedure using a polypropylene mesh and a cardiovascular patch is a safe, efficacious, and inexpensive surgical procedure for PPI. In cases of neurological incontinence, however, the higher infection rate in non-PPI patients means that they should be carefully managed. PMID:28361511
Effectiveness of BaTiO 3 dielectric patches on YBa 2Cu 3O 7 thin films for MEM switches
Vargas, J.; Hijazi, Y.; Noel, J.; ...
2014-05-12
A micro-electro-mechanical (MEM) switch built on a superconducting microstrip filter will be utilized to investigate BaTiO 3 dielectric patches for functional switching points of contact. Actuation voltage resulting from the MEM switch provokes static friction between the bridge membrane and BaTiO 3 insulation layer. Furthermore, the dielectric patch crystal structure and roughness affect the ability of repetitively switching cycles and lifetime. We performed a series of experiments using different deposition methods and RF magnetron sputtering was found to be the best deposition process for the BaTiO 3 layer. The effect examination of surface morphology will be presented using characterization techniquesmore » as x-ray diffraction, SEM and AFM for an optimum switching device. The thin film is made of YBa 2Cu 3O 7 deposited on LaAlO 3 substrate by pulsed laser deposition. In our work, the dielectric material sputtering pressure is set at 9.5x10 -6 Torr. The argon gas is released through a mass-flow controller to purge the system prior to deposition. RF power is 85 W at a distance of 9 cm. The behavior of Au membranes built on ultimate BaTiO 3 patches will be shown as part of the results. These novel surface patterns will in turn be used in modelling other RF MEM switch devices such as distributed-satellite communication system operating at cryogenic temperatures.« less
Kim, Hyun-Woong; Kim, Chai-Youn; Blake, Randolph
2017-03-20
Early visual experience sculpts neural mechanisms that regulate the balance of influence exerted by the two eyes on cortical mechanisms underlying binocular vision [1, 2], and experience's impact on this neural balancing act continues into adulthood [3-5]. One recently described, compelling example of adult neural plasticity is the effect of patching one eye for a relatively short period of time: contrary to intuition, monocular visual deprivation actually improves the deprived eye's competitive advantage during a subsequent period of binocular rivalry [6-8], the robust form of visual competition prompted by dissimilar stimulation of the two eyes [9, 10]. Neural concomitants of this improvement in monocular dominance are reflected in measurements of brain responsiveness following eye patching [11, 12]. Here we report that patching an eye is unnecessary for producing this paradoxical deprivation effect: interocular suppression of an ordinarily visible stimulus being viewed by one eye is sufficient to produce shifts in subsequent predominance of that eye to an extent comparable to that produced by patching the eye. Moreover, this imbalance in eye dominance can also be induced by prior, extended viewing of two monocular images differing only in contrast. Regardless of how shifts in eye dominance are induced, the effect decays once the two eyes view stimuli equal in strength. These novel findings implicate the operation of interocular neural gain control that dynamically adjusts the relative balance of activity between the two eyes [13, 14]. Copyright © 2017 Elsevier Ltd. All rights reserved.
Patch occupancy and dispersal of spruce grouse on the edge of its range in Maine
Whitcomb, S.A.; Servello, F.A.; O'Connell, A.F.
1996-01-01
We surveyed 18 habitat patches (black spruce (Picea marinana) - tamarack (Larix larcina) wetlands) for spruce grouse (Dendragapus canadensis canadensis) on Mount Desert Island, Maine, during April-May in 1992 and 1993 to determine patch occupancy relative to patch area. We also equipped nine juvenile grouse with radio transmitters to determine movement and habitat use outside of patches during autumn dispersal. The 2 large patches (77 and 269 ha), 5 of 6 medium-sized (11-26 ha) patches, and 1 of 10 small (4-8 ha) patches were occupied. Spruce grouse occupied smaller habitat patches than previously reported, and occupied patches were closer (P < 0.05) to the nearest occupied patch (x = 1.2 km) than were unoccupied patches (x = 2.5 km). Eight of nine juvenile grouse left their natal habitat patch during autumn dispersal, and net dispersal distance (x = 2.3 km) was greater than that reported for grouse in areas with more contiguous habitat. Dispersing juveniles used all major forest types and 33 % of relocations were in deciduous forest. Thus, deciduous forest was not an absolute dispersal barrier.
A study of the dynamic tire properties over a range of tire constructions
NASA Technical Reports Server (NTRS)
Nybakken, G. H.; Dodge, R. N.; Clark, S. K.
1973-01-01
The dynamic properties of four model aircraft tires of various construction were evaluated experimentally and compared with available theory. The experimental investigation consisted of measuring the cornering force and the self-aligning torque developed by the tires undergoing sinusoidal steering inputs while operating on a small scale, road-wheel tire testing apparatus. The force and moment data from the different tires are compared with both finite- and point-contact patch string theory predictions. In general, agreement between finite contact patch theory and experimental observation is good. A modified string theory is also presented in which coefficients for cornering force and self-aligning torque are determined separately. This theory improves the correspondence between the experimental and analytical data, particularly on tires with relatively high self-aligning torques.
No patch technique for complete atrioventricular canal repair.
Aramendi, José Ignacio; Rodriguez, Miguel Angel; Luis, Teresa; Voces, Roberto
2006-08-01
We describe our initial experience with a new technique, consisting in direct closure of the ventricular septal defect component of the AV canal, by directly attaching the common bridging leaflets to the crest of the ventricular septum with interrupted sutures. After closure of the cleft, the ostium primum defect was closed with a running suture suturing the border of the septum primum to the newly created AV valve annulus. Three patients were operated upon. There was no mortality. Mean ischemic time was 39 min and mean pump time 77 min. All patients remained in sinus rhythm. At follow-up only trivial or mild mitral regurgitation was observed. This new technique permits the repair of complete AV canal without the need for any patch. It is fast, simple and reproducible.
Wideband dual frequency modified ellipse shaped patch antenna for WLAN/Wi-MAX/UWB application
NASA Astrophysics Data System (ADS)
Jain, P. K.; Jangid, K. G.; R. Sharma, B.; Saxena, V. K.; Bhatnagar, D.
2018-05-01
This paper communicates the design and performance of microstrip line fed modified ellipses shaped radiating patch with defected ground structure. Wide impedance bandwidth performance is achieved by applying a pentagonal slot and T slot structure in ground plane. By inserting two semi ellipses shaped ring in ground, we obtained axial ratio bandwidth approx 600 MHz. The proposed antenna is simulated by utilizing CST Microwave Studio simulator 2014. This antenna furnishes wide impedance bandwidth approx. 4.23 GHz, which has spread into two bands 2.45 GHz - 5.73 GHz and 7.22 GHz - 8.17 GHz with nearly flat gain in operating frequency range. This antenna may be proved as a practicable structure for modern wireless communication systems including Wi-MAX, WLAN and lower band of UWB.
Shelat, Vishal G; Ahmed, Saleem; Chia, Clement L K; Cheah, Yee Lee
2015-02-01
Application of minimal access surgery in acute care surgery is limited due to various reasons. Laparoscopic omental patch repair (LOPR) for perforated peptic ulcer (PPU) surgery is safe and feasible but not widely implemented. We report our early experience of LOPR with emphasis on strict selection criteria. This is a descriptive study of all patients operated on for PPU at academic university-affiliated institutes from December 2010 to February 2012. All the patients who were operated on for LOPR were included as the study population and their records were studied. Perioperative outcomes, Boey score, Mannheim Peritonitis Index (MPI), and physiologic and operative severity scores for enumeration of mortality and morbidity (POSSUM) scores were calculated. All the data were tabulated in a Microsoft Excel spreadsheet and analyzed using Stata Version 8.x. (StataCorp, College Station, TX, USA). Fourteen patients had LOPR out of a total of 45 patients operated for the PPU. Mean age was 46 years (range 22-87 years). Twelve patients (86%) had a Boey score of 0 and all patients had MPI < 21 (mean MPI = 14). The predicted POSSUM morbidity and mortality were 36% and 7%, respectively. Mean ulcer size was 5 mm (range 2-10 mm), mean operating time was 100 minutes (range 70-123 minutes) and mean length of hospital stay was 4 days (range 3-6 days). There was no morbidity or mortality pertaining to LOPR. LOPR should be offered by acute care surgical teams when local expertise is available. This can optimize patient outcomes when strict selection criteria are applied.
Runoff and erosion in a pinon-juniper woodland: Influence of vegetation patches
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reid, K.D.; Wilcox, B.P.; Breshears, D.D.
1999-12-01
In many semiarid regions, runoff and erosion differ according to vegetation patch type. These differences, although hypothesized to fundamentally affect ecological processes, have been poorly quantified. In a semiarid pinion-juniper woodland [Pinus edulis Engelm. and Juniperus monosperma (Engelm) Sarg.] in northern New Mexico, the authors measured runoff and erosion from the three patch types that compose these woodlands: Canopy patches (those beneath woody plants), vegetated patched in intercanopy areas, and bare patches in intercanopy areas. The bare intercanopy patches exhibited the highest rates, followed by vegetated intercanopy patches and then by canopy patches. Large convective summer storms, though relatively infrequent,more » generated much of the runoff and most of the sediment; prolonged frontal storms were capable of generating considerable runoff but little sediment. A portion of the runoff and most of the sediment generated from bare intercanopy patches was redistributed down-slope, probably to adjacent vegetated intercanopy patches, demonstrating connectivity between these two patch types. Their results indicate that there are significant and important differences in runoff and sediment production from the three patch types; that bare intercanopy patches act as sources of both water and sediment for the vegetated intercanopy patches; and that the transfer of water and sediment at small scales is both frequent enough and substantial enough to be considered ecologically significant.« less
The Use of Human Factors Simulation to Conserve Operations Expense
NASA Technical Reports Server (NTRS)
Hamilton, George S.; Dischinger, H. Charles, Jr.; Wu, Hsin-I.
1999-01-01
In preparation for on-orbit operations, NASA performs experiments aboard a KC-135 which performs parabolic maneuvers, resulting in short periods of microgravity. While considerably less expensive than space operations, the use of this aircraft is costly. Simulation of tasks to be performed during the flight can allow the participants to optimize hardware configuration and crew interaction prior to flight. This presentation will demonstrate the utility of such simulation. The experiment simulated is the fluid dynamics of epoxy components which may be used in a patch kit in the event of meteoroid damage to the International Space Station. Improved configuration and operational efficiencies were reflected in early and increased data collection.
An extended patch-dynamic framework for food chains in fragmented landscapes
Liao, Jinbao; Chen, Jiehong; Ying, Zhixia; Hiebeler, David E.; Nijs, Ivan
2016-01-01
Habitat destruction, a key determinant of species loss, can be characterized by two components, patch loss and patch fragmentation, where the former refers to the reduction in patch availability, and the latter to the division of the remaining patches. Classical metacommunity models have recently explored how food web dynamics respond to patch loss, but the effects of patch fragmentation have largely been overlooked. Here we develop an extended patch-dynamic model that tracks the patch occupancy of the various trophic links subject to colonization-extinction-predation dynamics by incorporating species dispersal with patch connectivity. We found that, in a simple food chain, species at higher trophic level become extinct sooner with increasing patch loss and fragmentation due to the constraint in resource availability, confirming the trophic rank hypothesis. Yet, effects of fragmentation on species occupancy are largely determined by patch loss, with maximal fragmentation effects occurring at intermediate patch loss. Compared to the spatially explicit simulations that we also performed, the current model with pair approximation generates similar community patterns especially in spatially clustered landscapes. Overall, our extended framework can be applied to model more complex food webs in fragmented landscapes, broadening the scope of existing metacommunity theory. PMID:27608823
Robust Spacecraft Component Detection in Point Clouds.
Wei, Quanmao; Jiang, Zhiguo; Zhang, Haopeng
2018-03-21
Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D) point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD) models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density.
Multiport Circular Polarized RFID-Tag Antenna for UHF Sensor Applications.
Zaid, Jamal; Abdulhadi, Abdulhadi; Kesavan, Arun; Belaizi, Yassin; Denidni, Tayeb A
2017-07-05
A circular polarized patch antenna for UHF RFID tag-based sensor applications is presented, with the circular polarization (CP) generated by a new antenna shape, an asymmetric stars shaped slotted microstrip patch antenna (CP-ASSSMP). Four stars etched on the patch allow the antenna's size to be reduced by close to 20%. The proposed antenna is matched with two RFID chips via inductive-loop matching. The first chip is connected to a resistive sensor and acts as a sensor node, and the second is used as a reference node. The proposed antenna is used for two targets, serving as both reference and sensor simultaneously, thereby eliminating the need for a second antenna. Its reader can read the RFID chips at any orientation of the tag due to the CP. The measured reading range is about 25 m with mismatch polarization. The operating frequency band is 902-929 MHz for the two ports, which is covered by the US RFID band, and the axial-ratio bandwidth is about 7 MHz. In addition, the reader can also detect temperature, based on the minimum difference in the power required by the reference and sensor.
Multiport Circular Polarized RFID-Tag Antenna for UHF Sensor Applications
Zaid, Jamal; Abdulhadi, Abdulhadi; Kesavan, Arun; Belaizi, Yassin; Denidni, Tayeb A.
2017-01-01
A circular polarized patch antenna for UHF RFID tag-based sensor applications is presented, with the circular polarization (CP) generated by a new antenna shape, an asymmetric stars shaped slotted microstrip patch antenna (CP-ASSSMP). Four stars etched on the patch allow the antenna’s size to be reduced by close to 20%. The proposed antenna is matched with two RFID chips via inductive-loop matching. The first chip is connected to a resistive sensor and acts as a sensor node, and the second is used as a reference node. The proposed antenna is used for two targets, serving as both reference and sensor simultaneously, thereby eliminating the need for a second antenna. Its reader can read the RFID chips at any orientation of the tag due to the CP. The measured reading range is about 25 m with mismatch polarization. The operating frequency band is 902–929 MHz for the two ports, which is covered by the US RFID band, and the axial-ratio bandwidth is about 7 MHz. In addition, the reader can also detect temperature, based on the minimum difference in the power required by the reference and sensor. PMID:28678178
Robust Spacecraft Component Detection in Point Clouds
Wei, Quanmao; Jiang, Zhiguo
2018-01-01
Automatic component detection of spacecraft can assist in on-orbit operation and space situational awareness. Spacecraft are generally composed of solar panels and cuboidal or cylindrical modules. These components can be simply represented by geometric primitives like plane, cuboid and cylinder. Based on this prior, we propose a robust automatic detection scheme to automatically detect such basic components of spacecraft in three-dimensional (3D) point clouds. In the proposed scheme, cylinders are first detected in the iteration of the energy-based geometric model fitting and cylinder parameter estimation. Then, planes are detected by Hough transform and further described as bounded patches with their minimum bounding rectangles. Finally, the cuboids are detected with pair-wise geometry relations from the detected patches. After successive detection of cylinders, planar patches and cuboids, a mid-level geometry representation of the spacecraft can be delivered. We tested the proposed component detection scheme on spacecraft 3D point clouds synthesized by computer-aided design (CAD) models and those recovered by image-based reconstruction, respectively. Experimental results illustrate that the proposed scheme can detect the basic geometric components effectively and has fine robustness against noise and point distribution density. PMID:29561828
NASA Astrophysics Data System (ADS)
Chandan, Bharti, Gagandeep; Srivastava, Toolika; Rai, B. S.
2018-04-01
A novel truncated ground plane monopole antenna is proposed for wide band wireless local area network (WLAN) applications. The antenna contains a rectangular patch with a rectangular ring, a circular slot and a truncated ground plane printed on opposite sides of a low cost substrate FR4. The operating frequency bands for the antenna are band1 (2.4-2.88 GHz) and band 2 (4.8-6.3 GHz) with ≤ - 10 dB return loss which covers 2.4/5.2/5.5/5.8 GHz WLAN bands. The antenna is compact with overall dimension 26×40×0.8 mmł and with the dimension of patch 16×16×0.8 mm3. The two bands of antenna is obtained by cutting a rectangular ring and a circular slot in the patch and return loss is improved by cutting two rectangular slot in the ground plane. Performance measures of the antenna are shown in terms of return loss, current distribution, radiation pattern and gain. To verify the simulated results, the antenna is also fabricated and tested. The simulated and fabricated results have been found in good agreement.
1995-11-12
The STS-76 crew patch depicts the Space Shuttle Atlantis and Russia's Mir Space Station as the space ships prepare for a rendezvous and docking. The Spirit of 76, an era of new beginnings, is represented by the Space Shuttle rising through the circle of 13 stars in the Betsy Ross flag. STS-76 begins a new period of international cooperation in space exploration with the first Shuttle transport of a United States astronaut, Shannon W. Lucid, to the Mir Space Station for extended joint space research. Frontiers for future exploration are represented by stars and the planets. The three gold trails and the ring of stars in union form the astronaut logo. Two suited extravehicular activity (EVA) crew members in the outer ring represent the first EVA during Shuttle-Mir docked operations. The EVA objectives were to install science experiments on the Mir exterior and to develop procedures for future EVA's on the International Space Station. The surnames of the crew members encircle the patch: Kevin P. Chilton, mission commander; Richard A. Searfoss, pilot; Ronald M. Sega, Michael R. ( Rich) Clifford, Linda M. Godwin and Lucid, all mission specialists. This patch was designed by Brandon Clifford, age 12, and the crew members of STS-76.
NASA Technical Reports Server (NTRS)
Chamberlain, Neil F. (Inventor); Zawadzki, Mark S. (Inventor); Hodges, Richard E. (Inventor)
2012-01-01
Disclosed herein is a patch antenna comprises a planar conductive patch attached to a ground plane by a support member, and a probe connector in electrical communication with the conductive patch arranged to conduct electromagnetic energy to or from the conductive patch, wherein the conductive patch is disposed essentially parallel to the ground plane and is separated from the ground plane by a spacing distance; wherein the support member comprises a plurality of sides disposed about a central axis oriented perpendicular to the conductive patch and the ground plane; wherein the conductive patch is solely supported above the ground plane by the support member; and wherein the support member provides electrical communication between the planer conductive patch and the ground plane.
A State Cyber Hub Operations Framework
2016-06-01
to communicate and sense or interact with their internal states or the external environment. Machine Learning: A type of artificial intelligence that... artificial intelligence , and computational linguistics concerned with the interactions between computers and human (natural) languages. Patching: A piece...formalizing a proof of concept for cyber initiatives and developed frameworks for operationalizing the data and intelligence produced across state
Top 10 Threats to Computer Systems Include Professors and Students
ERIC Educational Resources Information Center
Young, Jeffrey R.
2008-01-01
User awareness is growing in importance when it comes to computer security. Not long ago, keeping college networks safe from cyberattackers mainly involved making sure computers around campus had the latest software patches. New computer worms or viruses would pop up, taking advantage of some digital hole in the Windows operating system or in…
Pélissier, E-P; Ngo, P
2006-12-01
Incidence of chronic pain is lower following laparoscopic hernioplasty than open surgery, probably due to the location of the patch in the preperitoneal space. But since laparoscopy is more demanding, the rates of complications and recurrences are higher. The aim of this study was to evaluate the results of a procedure consisting of placement of a patch, endowed with some memory of shape, provided by a thin peripheral memory ring, in the preperitoneal space, by inguinal incision, through the hernia orifice, under spinal or local anesthesia. The study was carried out in two stages. The first study consisted of evaluating the results of a prosthesis made of a polypropylene mesh endowed with a memory-ring made of a PDS cord (Ethicon SAS, 92787 Issy-les-Moulineaux). The second study evaluated the results of the Polysoft patch manufactured by Bard C degrees (Bard France, 78960 Voisins-le-Bretonneux), according to this concept. The first study involved 129 hernias operated on 126 patients of mean age 60 years (27-84). There were 3 (2.3%) benign complications. With a median follow-up of 24.5 months (12-42), 124 hernias (96%) were evaluated. There were 2 recurrences (1.6%) and 7 cases (5.6%) of chronic pain. The second series involved 150 hernias operated on 139 patients of mean age 60 years (21-94). Four (2.7%) benign complications occurred. The median length of surgery was 36 min (20-60), the median postoperative hospital stay was 1 day (0-5), the median time to return to normal activity was 3 days (0-8) and the median time off work was 18 days (1(30). The patients took paracetamol for 3 days (0-10) and the total units number was 8 (0-28). These results suggest that the method, easily reproducible, provides a low rate of complications and recurrences, as well as a low level of postoperative and chronic pain. They are worth being confirmed by a randomised comparison to the laparoscopic and Lichtenstein techniques.
Light transmission and preference of eye patches for occlusion treatment.
Heo, Hwan; Park, Jung Won; Park, Sang Woo
2013-01-01
To investigate light transmission and preference for six eye patches for occlusion therapy. Six patches were examined, including; Ortopad Fun Pack, Ortopad Flesh, Kawamoto A-1, Kawamoto A-2, 3M Opticlude, and Everade Eye Guard. The size and the presence of a light blocking pad of patches were investigated. The amount of light transmitted through the patches was evaluated, using a digital light meter and a model eye, in three different environments; indoors with fluorescent light, outdoors on a sunny day, and strong light from illuminator. After patching the normal eye, the flash visual evoked potential (VEP) was measured. Thirty patients with amblyopia or horizontal strabismus, who received occlusion therapy as initial treatment, were included. After using all six patches, patients completed a 7-item questionnaire regarding the patch preference for size, color and shape, adhesive power, pain with removal, skin irritation after removing patch, parent's preference and overall opinion. All patches had a light-blocking pad, except the 3M Nexcare. Ortopad had the strongest light blocking power in the three environments, and the 3M Nexcare had the weakest power. In flash VEP, Ortopad and Kawamoto patches showed flat, but 3M Nexcare and Everade Eye Guard showed normal response. There were significant preferential differences among the patches in all the items of the questionnaire (P<0.05). In comparison between the patches respectively, 3M Nexcare received the lowest satisfaction in pain when removing a patch and skin irritation after removing a patch. Kawamoto A-2 received the lowest score in the overall satisfaction. We found differences in the light-blocking power and in the preference of the various patches for the occlusion treatment. This is a pilot study regarding only characteristics and preferences of patches. Further clinical studies regarding the relationship between characteristics or preferences of patches and outcomes of occlusion treatment are needed.
Arya, Jaya; Henry, Sebastien; Kalluri, Haripriya; McAllister, Devin V.; Pewin, Winston P.; Prausnitz, Mark R.
2017-01-01
To support translation of microneedle patches from pre-clinical development into clinical trials, this study examined the effect of microneedle patch application on local skin reactions, reliability of use and acceptability to patients. Placebo patches containing dissolving microneedles were administered to fifteen human participants. Microneedle patches were well tolerated in the skin with no pain or swelling and only mild erythema localized to the site of patch administration that resolved fully within seven days. Microneedle patches could be administered by hand without the need of an applicator and delivery efficiencies were similar for investigator-administration and self-administration. Microneedle patch administration was not considered painful and the large majority of subjects were somewhat or fully confident that they self-administered patches correctly. Microneedle patches were overwhelmingly preferred over conventional needle and syringe injection. Altogether, these results demonstrate that dissolving microneedle patches were well tolerated, easily usable and strongly accepted by human subjects, which will facilitate further clinical translation of this technology. PMID:28285193
Pintar, Matthew R; Resetarits, William J
2017-09-01
Habitat selection by colonizing organisms is an important factor in determining species abundance and community dynamics at multiple spatial scales. Many organisms select habitat patches based on intrinsic patch quality, but patches exist in complex landscapes linked by dispersal and colonization, forming metapopulations and metacommunities. Perceived patch quality can be influenced by neighbouring patches through spatial contagion, wherein perceived quality of one patch can extend beyond its borders and either increase or decrease the colonization of neighbouring patches and localities. These spatially explicit colonization dynamics can result in habitat compression, wherein more colonists occupy a patch or locality than in the absence of spatial context dependence. Previous work on contagion/compression focused primarily on the role of predators in driving colonization patterns. Our goal was to determine whether resource abundance can drive multi-scale colonization dynamics of aquatic beetles through the processes of contagion and compression in naturally colonized experimental pools. We established two levels (high/low quality) of within-patch resource abundances (leaf litter) using an experimental landscape of mesocosms, and assayed colonization by 35 species of aquatic beetles. Patches were arranged in localities (sets of two patches), which consisted of a combination of two patch-level resource levels in a 2 × 2 factorial design, allowing us to assay colonization at both locality and patch levels. We demonstrate that patterns of species abundance and richness of colonizing aquatic beetles are determined by patch quality and context-dependent processes at multiple spatial scales. Localities that consisted of at least one high-quality patch were colonized at equivalent rates that were higher than localities containing only low-quality patches, displaying regional reward contagion. In localities that consisted of one high- and one low-quality patch, reward contagion produced by higher leaf litter levels resulted in greater abundance of beetles in such localities, which then compressed into the highest quality patches. Our results provide further support for the critical roles of habitat selection and spatial context, particularly the quality of neighbouring habitat patches, in generating patterns of species abundances and community structure across landscapes. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.
Huang, Minyi; Duan, Renyan; Wang, Shixiong; Wang, Zhigao; Fan, Weiyi
2016-01-01
Forest communities are mosaic systems composed of patches classified into four different developmental patch types: gap patch (G), building patch (B), mature patch (M) and degenerate patch (D). To study the mechanisms maintaining diversity in subalpine coniferous forests, species presence frequency and diversity in the four distinct patch types (G, B, M and D) of Larix chinensis conifer forests at three altitudinal gradients in the Qinling Mountains were analyzed. Our results were as follows: (1) Different species (or functional groups) had distinct presence frequencies in the four different patch types along the altitudinal gradient; (2) Some species or functional groups (species groups sharing similar traits and responses to the environment) only occurred in some specific patches. For seed dispersal, species using wind mainly occurred in G and D, while species using small animals mainly occurred in B and M; (3) Species composition of adjacent patch types was more similar than non-adjacent patch types, based on the lower β diversity index of the former; (4) The maximum numbers of species and two diversity indices (D' and H') were found in the middle altitudes. Various gap-forming processes and dispersal limitation may be the two major mechanisms determining species diversity in Larix chinensis coniferous forests at the patch scale.
Kelley, Thomas M; Kashem, Mohammed; Wang, He; McCarthy, James; Carroll, Nels D; Moser, G William; Guy, T Sloane
2017-01-01
This study reported on the treatment of Carpentier type IIIa and type IIIb mitral regurgitation (MR) with a large patch anterior mitral valve leaflet augmentation technique using CorMatrix (CorMatrix Cardiovascular Inc, Alpharetta, GA) extracellular matrix (ECM). A single-site chart review was conducted on patients who underwent anterior leaflet augmentation performed with the Da Vinci surgical robot (Intuitive Surgical, Sunnyvale, CA) or through a median sternotomy. Only patients who had anterior leaflet augmentation with porcine intestine ECM or autologous pericardium were included. Follow-up echocardiography was performed on all patients. Histologic specimens were available on ECM patches from a subset of patients who required reoperation. Between August 2011 and April 2014, 44 patients (mean age, 62.6 ± 12.2 years) underwent anterior leaflet augmentation with either porcine intestinal ECM or autologous pericardium at the Temple University Hospital in Philadelphia. Two (4%) late deaths occurred, one in each group. One patient who underwent ECM augmentation died of non-cardiac-related causes 7 months after discharge as a result of complications of chronic renal failure. The second late death occurred 5 months after discharge because of complications of a stroke in a patient in the pericardial augmentation group. Eight (32%) of the patients with ECM had recurrence of severe MR on echocardiography at an average time of 201 ± 98 days. Seven (28%) patients required reoperation because of failure of the ECM patch including perforation (4%), excessive patch dilation (20%), and suture line dehiscence (4%). In contrast, none of the patients with pericardial augmentation developed severe MR or required operation. Statistical analysis of the patients with ECM augmentation demonstrated no correlation of the following: age; sex; comorbid conditions such as diabetes, chronic obstructive pulmonary disease, and hypertension; left ventricular ejection fraction; surgical approach; annuloplasty size; or type of MR with patch failure. A lower body mass index was the only factor associated with recurrent severe regurgitation on univariate analysis (p = 0.039). Histologic study of the four available explants demonstrated intense inflammation without evidence of host integration. The remaining 15 (60%) patients had normal mitral leaflet structure and function on follow-up echocardiograms out to 12 months. For type III MR, a large anterior leaflet patch technique with porcine ECM was associated with a 32% recurrence rate of severe MR related directly to patch failure. Further research and development should be performed on the use of ECM materials with a goal to decrease the failure rate experienced in this study. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
LabPatch, an acquisition and analysis program for patch-clamp electrophysiology.
Robinson, T; Thomsen, L; Huizinga, J D
2000-05-01
An acquisition and analysis program, "LabPatch," has been developed for use in patch-clamp research. LabPatch controls any patch-clamp amplifier, acquires and records data, runs voltage protocols, plots and analyzes data, and connects to spreadsheet and database programs. Controls within LabPatch are grouped by function on one screen, much like an oscilloscope front panel. The software is mouse driven, so that the user need only point and click. Finally, the ability to copy data to other programs running in Windows 95/98, and the ability to keep track of experiments using a database, make LabPatch extremely versatile. The system requirements include Windows 95/98, at least a 100-MHz processor and 16 MB RAM, a data acquisition card, digital-to-analog converter, and a patch-clamp amplifier. LabPatch is available free of charge at http://www.fhs.mcmaster.ca/huizinga/.
Blind operation of optical astronomical interferometers options and predicted performance
NASA Astrophysics Data System (ADS)
Beckers, Jacques M.
1991-01-01
Maximum sensitivity for optical interferometers is achieved only when the optical path lengths between the different arms can be equalized without using interference fringes on the research object itself. This is called 'blind operation' of the interferometer. This paper examines different options to achieve this, focusing on the application to the Very Large Telescope Interferometer (VLTI). It is proposed that blind operation should be done using a so-called coherence autoguider, working on an unresolved star of magnitude V = 11-13 within the isoplanatic patch for coherencing, which has a diameter of about 1 deg. Estimates of limiting magnitudes for the VLTI are also derived.
Common spaceborne multicomputer operating system and development environment
NASA Technical Reports Server (NTRS)
Craymer, L. G.; Lewis, B. F.; Hayes, P. J.; Jones, R. L.
1994-01-01
A preliminary technical specification for a multicomputer operating system is developed. The operating system is targeted for spaceborne flight missions and provides a broad range of real-time functionality, dynamic remote code-patching capability, and system fault tolerance and long-term survivability features. Dataflow concepts are used for representing application algorithms. Functional features are included to ensure real-time predictability for a class of algorithms which require data-driven execution on an iterative steady state basis. The development environment supports the development of algorithm code, design of control parameters, performance analysis, simulation of real-time dataflow applications, and compiling and downloading of the resulting application.
Stears, Keenan; Kerley, Graham I H; Shrader, Adrian M
2014-01-01
Two key factors that influence the foraging behaviour of group-living herbivores are food availability and individual dominance status. Yet, how the combination of these factors influences the patch-joining decisions of individuals foraging within groups has scarcely been explored. To address this, we focused on the patch-joining decisions of group-living domestic goats (Capra hircus). When individuals were tested against the top four ranked goats of the herd, we found that at patches with low food availability they avoided these dominant patch-holders and only joined subordinates (i.e. costs outweighed benefits). However, as the amount of food increased, the avoidance of the top ranked individuals declined. Specifically, goats shifted and joined the patch of an individual one dominance rank higher than the previous dominant patch holder when the initial quantity of food in the new patch was twice that of the lower ranking individual's patch (i.e. benefits outweighed costs). In contrast, when individuals chose between patches held by dominant goats, other than the top four ranked goats, and subordinate individuals, we found that they equally joined the dominant and subordinate patch-holders. This joining was irrespective of the dominance gap, absolute rank of the dominant patch-holder, sex or food availability (i.e. benefits outweighed costs). Ultimately, our results highlight that herbivores weigh up the costs and benefits of both food availability and patch-holder dominance status when making patch-joining decisions. Furthermore, as the initial quantity of food increases, food availability becomes more important than dominance with regard to influencing patch-joining decisions.
Bai, Hualong; Lee, Jung Seok; Chen, Elizabeth; Wang, Mo; Xing, Ying; Fahmy, Tarek M.; Dardik, Alan
2017-01-01
Prosthetic grafts and patches are commonly used in cardiovascular surgery, however neointimal hyperplasia remains a significant concern, especially under low flow conditions. We hypothesized that delivery of rapamycin from nanoparticles (NP) covalently attached to patches allows sustained site-specific delivery of therapeutic agents targeted to inhibit localized neointimal hyperplasia. NP were covalently linked to pericardial patches using EDC/NHS chemistry and could deliver at least 360 ng rapamycin per patch without detectable rapamycin in serum; nanoparticles were detectable in the liver, kidney and spleen but no other sites within 24 hours. In a rat venous patch angioplasty model, control patches developed robust neointimal hyperplasia on the patch luminal surface characterized by Eph-B4-positive endothelium and underlying SMC and infiltrating cells such as macrophages and leukocytes. Patches delivering rapamycin developed less neointimal hyperplasia, less smooth muscle cell proliferation, and had fewer infiltrating cells but retained endothelialization. NP covalently linked to pericardial patches are a novel composite delivery system that allows sustained site-specific delivery of therapeutics; NP delivering rapamycin inhibit patch neointimal hyperplasia. NP linked to patches may represent a next generation of tissue engineered cardiovascular implants. PMID:28071663
Effect of novel mucoadhesive buccal patches of carvedilol on isoprenaline-induced tachycardia
Verma, Navneet; Chattopadhyay, Pronobesh
2014-01-01
The main aim of the study was designed to develop bioadhesive buccal patches of carvedilol (CR) and evaluate for isoprenaline-induced tachycardia. Buccal patches of carvedilol were prepared by using chitosan (CH), sodium salt of carboxy methyl cellulose (NaCMC), and polyvinyl alcohol (PVA) as mucoadhesive polymers. The solvent evaporation method was used for the preparation of buccal patches. The patches were evaluated for their physical characteristics like patch thickness, weight variation, content uniformity, folding endurance, surface pH, residence time, in vitro drug release, and in vivo pharmacodynamic study. The swelling index of the patches was found to be proportional to the polymer concentration, whereas surface pH of all the formulated bioadhesive patches was found to lie between neutral ranges. In-vitro release study shows that 94.75% drug was release in 8 hours from the patch, which containing 2% w/v chitosan. The folding endurance result shows good elasticity in all the patches. Application of buccal patches on buccal mucosa of rabbit shows a significant result in % inhibition of isoprenaline-induced tachycardia. Prepared buccal patches of chitosan, NaCMC, and PVA containing Carvedilol meet the ideal requirement for the delivery of cardiovascular drugs and inhibit the isoprenaline tachycardia. PMID:24959419
Effect of novel mucoadhesive buccal patches of carvedilol on isoprenaline-induced tachycardia.
Verma, Navneet; Chattopadhyay, Pronobesh
2014-04-01
The main aim of the study was designed to develop bioadhesive buccal patches of carvedilol (CR) and evaluate for isoprenaline-induced tachycardia. Buccal patches of carvedilol were prepared by using chitosan (CH), sodium salt of carboxy methyl cellulose (NaCMC), and polyvinyl alcohol (PVA) as mucoadhesive polymers. The solvent evaporation method was used for the preparation of buccal patches. The patches were evaluated for their physical characteristics like patch thickness, weight variation, content uniformity, folding endurance, surface pH, residence time, in vitro drug release, and in vivo pharmacodynamic study. The swelling index of the patches was found to be proportional to the polymer concentration, whereas surface pH of all the formulated bioadhesive patches was found to lie between neutral ranges. In-vitro release study shows that 94.75% drug was release in 8 hours from the patch, which containing 2% w/v chitosan. The folding endurance result shows good elasticity in all the patches. Application of buccal patches on buccal mucosa of rabbit shows a significant result in % inhibition of isoprenaline-induced tachycardia. Prepared buccal patches of chitosan, NaCMC, and PVA containing Carvedilol meet the ideal requirement for the delivery of cardiovascular drugs and inhibit the isoprenaline tachycardia.
Latty, Tanya; Beekman, Madeleine
2010-01-01
How individuals deal with multiple conflicting demands is an important aspect of foraging ecology, yet work on foraging behavior has typically neglected neurologically simple organisms. Here we examine the impact of an abiotic risk (light) and energetic status on the foraging decisions of a protist, the slime mold Physarum polycephalum. We examined patch choice in a "non-risky" environment by presenting starved and non-starved P. polycephalum amoebas with a choice between two shaded food patches (one high quality, one low quality). We next examined patch choice in the presence of a conflict between foraging risk (light exposure) and food quality by presenting amoebas with a choice between a shaded, low-quality patch, and a light-exposed, high-quality patch. When both patches were shaded, 100% of amoebas selected the higher quality food patch, irrespective of food-quality differences or the individual's energetic status. When light exposure and food quality conflicted, amoebas selected the patch with the higher food quality when the quality difference between the patches was high. When the quality difference between patches was small, amoebas selected the shaded, lower quality patch.
Kobayashi, Katsumi; Yokoi, Yota; Masuzawa, Takehiro
2011-05-01
To determine the main benefits of clonal expansion of Miscanthus sinensis patches (monoclones), we observed the annual pattern of the areal expansion of a number of M. sinensis patches and examined how the quantity of rhizomes in such patches is related to changes in their basal area. To forage for nutriments, a patch must continuously widen its habitat. Patches annually expanded centrifugally by sympodial branching of short rhizomes, which originated in tillering that occurred more than once a year. However, the basal area of the patches approached a ceiling as the patches aged. Both the number and the weight of rhizomes in the patches continued to increase as long as the basal area expanded. The mean weight of rhizomes in patches also initially increased quickly, but then reached a ceiling as the clones expanded. Similarly, the amount of reserve substance per shoot in the patches increased asymptotically along with the clonal expansion, depending on the rhizome mass allotted to each shoot. These results suggest that, in the clonal growth of M. sinensis patches, the accumulation of reserve matter in the rhizomes is more important than foraging in new areas.
NASA Astrophysics Data System (ADS)
Bai, Hualong; Lee, Jung Seok; Chen, Elizabeth; Wang, Mo; Xing, Ying; Fahmy, Tarek M.; Dardik, Alan
2017-01-01
Prosthetic grafts and patches are commonly used in cardiovascular surgery, however neointimal hyperplasia remains a significant concern, especially under low flow conditions. We hypothesized that delivery of rapamycin from nanoparticles (NP) covalently attached to patches allows sustained site-specific delivery of therapeutic agents targeted to inhibit localized neointimal hyperplasia. NP were covalently linked to pericardial patches using EDC/NHS chemistry and could deliver at least 360 ng rapamycin per patch without detectable rapamycin in serum; nanoparticles were detectable in the liver, kidney and spleen but no other sites within 24 hours. In a rat venous patch angioplasty model, control patches developed robust neointimal hyperplasia on the patch luminal surface characterized by Eph-B4-positive endothelium and underlying SMC and infiltrating cells such as macrophages and leukocytes. Patches delivering rapamycin developed less neointimal hyperplasia, less smooth muscle cell proliferation, and had fewer infiltrating cells but retained endothelialization. NP covalently linked to pericardial patches are a novel composite delivery system that allows sustained site-specific delivery of therapeutics; NP delivering rapamycin inhibit patch neointimal hyperplasia. NP linked to patches may represent a next generation of tissue engineered cardiovascular implants.
Grassland Fire and Cattle Grazing Regulate Reptile and Amphibian Assembly Among Patches
NASA Astrophysics Data System (ADS)
Larson, Danelle M.
2014-12-01
Fire and grazing are common management schemes of grasslands globally and are potential drivers of reptilian and amphibian (herpetofauna) metacommunity dynamics. Few studies have assessed the impacts of fire and cattle grazing on herpetofauna assemblages in grasslands. A patch-burn grazing study at Osage Prairie, MO, USA in 2011-2012 created landscape patches with treatments of grazing, fire, and such legacies. Response variables were measured before and after the application of treatments, and I used robust-design occupancy modeling to estimate patch occupancy and detection rate within patches, and recolonization and extinction (i.e., dispersal) across patches. I conducted redundancy analysis and a permuted multivariate analysis of variance to determine if patch type and the associated environmental factors explained herpetofauna assemblage. Estimates for reptiles indicate that occupancy was seasonally constant in Control patches ( ψ ~ 0.5), but declined to ψ ~ 0.15 in patches following the applications of fire and grazing. Local extinctions for reptiles were higher in patches with fire or light grazing ( ɛ ~ 0.7) compared to the controls. For the riparian herpetofaunal community, patch type and grass height were important predictors of abundance; further, the turtles, lizards, snakes, and adult amphibians used different patch types. The aquatic amphibian community was predicted by watershed and in-stream characteristics, irrespective of fire or grazing. The varying responses from taxonomic groups demonstrate habitat partitioning across multiple patch types undergoing fire, cattle grazing, and legacy effects. Prairies will need an array of patch types to accommodate multiple herpetofauna species.
Hydrologic controls on aperiodic spatial organization of the ridge-slough patterned landscape
NASA Astrophysics Data System (ADS)
Casey, Stephen T.; Cohen, Matthew J.; Acharya, Subodh; Kaplan, David A.; Jawitz, James W.
2016-11-01
A century of hydrologic modification has altered the physical and biological drivers of landscape processes in the Everglades (Florida, USA). Restoring the ridge-slough patterned landscape, a dominant feature of the historical system, is a priority but requires an understanding of pattern genesis and degradation mechanisms. Physical experiments to evaluate alternative pattern formation mechanisms are limited by the long timescales of peat accumulation and loss, necessitating model-based comparisons, where support for a particular mechanism is based on model replication of extant patterning and trajectories of degradation. However, multiple mechanisms yield a central feature of ridge-slough patterning (patch elongation in the direction of historical flow), limiting the utility of that characteristic for discriminating among alternatives. Using data from vegetation maps, we investigated the statistical features of ridge-slough spatial patterning (ridge density, patch perimeter, elongation, patch size distributions, and spatial periodicity) to establish more rigorous criteria for evaluating model performance and to inform controls on pattern variation across the contemporary system. Mean water depth explained significant variation in ridge density, total perimeter, and length : width ratios, illustrating an important pattern response to existing hydrologic gradients. Two independent analyses (2-D periodograms and patch size distributions) provide strong evidence against regular patterning, with the landscape exhibiting neither a characteristic wavelength nor a characteristic patch size, both of which are expected under conditions that produce regular patterns. Rather, landscape properties suggest robust scale-free patterning, indicating genesis from the coupled effects of local facilitation and a global negative feedback operating uniformly at the landscape scale. Critically, this challenges widespread invocation of scale-dependent negative feedbacks for explaining ridge-slough pattern origins. These results help discern among genesis mechanisms and provide an improved statistical description of the landscape that can be used to compare among model outputs, as well as to assess the success of future restoration projects.
Landscape associations of birds during migratory stopover
NASA Astrophysics Data System (ADS)
Diehl, Robert Howard
The challenge for migratory bird conservation is habitat preservation that sustains breeding, migration, and non-breeding biological processes. In choosing an appropriately scaled conservation arena for habitat preservation, a conservative and thorough examination of stopover habitat use patterns by migrants works back from the larger scales at which such relationships may occur. Because the use of stopover habitats by migrating birds occurs at spatial scales larger than traditional field techniques can easily accommodate, I quantify these relationship using the United States system of weather surveillance radars (popularly known as NEXRAD). To provide perspective on use of this system for biologists, I first describe the technical challenges as well as some of the biological potential of these radars for ornithological research. Using data from these radars, I then examined the influence of Lake Michigan and the distribution of woodland habitat on migrant concentrations in northeastern Illinois habitats during stopover. Lake Michigan exerted less influence on migrant abundance and density than the distribution and availability of habitat for stopover. There was evidence of post-migratory movement resulting in habitats within suburban landscapes experiencing higher migrant abundance but lower migrant density than habitats within nearby urban and agricultural landscapes. Finally, in the context of hierarchy theory, I examined the influence of landscape ecological and behavioral processes on bird density during migratory stopover. Migrant abundance did not vary across landscapes that differed considerably in the amount of habitat available for stopover. As a result, smaller, more isolated patches held higher densities of birds. Spatial models of migrant habitat selection based on migrant proximity to a patch explained nearly as much variance in the number of migrants occupying patches (R2 = 0.88) as selection models based on migrant interception of patches during flight (R2 = 0.90). Because migrant densities in specific patches were the consequence of biological processes operating at larger spatial scales, sound conservation strategies for migrating landbirds should consider the landscape context of stopover habitats that are potential targets for preservation.
Clash of kingdoms or why Drosophila larvae positively respond to fungal competitors.
Rohlfs, Marko
2005-01-27
BACKGROUND: Competition with filamentous fungi has been demonstrated to be an important cause of mortality for the vast group of insects that depend on ephemeral resources (e.g. fruit, dung, carrion). Recent data suggest that the well-known aggregation of Drosophila larvae across decaying fruit yields a competitive advantage over mould, by which the larvae achieve a higher survival probability in larger groups compared with smaller ones. Feeding and locomotor behaviour of larger larval groups is assumed to cause disruption of fungal hyphae, leading to suppression of fungal growth, which in turn improves the chances of larval survival to the adult stage. Given the relationship between larval density, mould suppression and larval survival, the present study has tested whether fungal-infected food patches elicit communal foraging behaviour on mould-infected sites by which larvae might hamper mould growth more efficiently. RESULTS: Based on laboratory experiments in which Drosophila larvae were offered the choice between fungal-infected and uninfected food patches, larvae significantly aggregated on patches containing young fungal colonies. Grouping behaviour was also visible when larvae were offered only fungal-infected or only uninfected patches; however, larval aggregation was less strong under these conditions than in a heterogeneous environment (infected and uninfected patches). CONCLUSION: Because filamentous fungi can be deadly competitors for insect larvae on ephemeral resources, social attraction of Drosophila larvae to fungal-infected sites leading to suppression of mould growth may reflect an adaptive behavioural response that increases insect larval fitness and can thus be discussed as an anti-competitor behaviour. These observations support the hypothesis that adverse environmental conditions operate in favour of social behaviour. In a search for the underlying mechanisms of communal behaviour in Drosophila, this study highlights the necessity of investigating the role of inter-kingdom competition as a potential driving force in the evolution of spatial behaviour in insects.
NASA Astrophysics Data System (ADS)
Rossi, Francesca; Matteini, Paolo; Ratto, Fulvio; Pini, Roberto; Iacoangeli, Maurizio; Giannoni, Luca; Fortuna, Damiano; Di Cicco, Emiliano; Corbara, Sylwia; Dallari, Stefano
2014-05-01
Laser bonding is a promising minimally invasive approach, emerging as a valid alternative to conventional suturing techniques. It shows widely demonstrated advantages in wound treatment: immediate closuring effect, minimal inflammatory response and scar formation, reduced healing time. This laser based technique can overcome the difficulties in working through narrow surgical corridors (e.g. the modern "key-hole" surgery as well as the endoscopy setting) or in thin tissues that are impossible to treat with staples and/or stitches. We recently proposed the use of chitosan matrices, stained with conventional chromophores, to be used in laser bonding of vascular tissue. In this work we propose the same procedure to perform laser bonding of vocal folds and dura mater repair. Laser bonding of vocal folds is proposed to avoid the development of adhesions (synechiae), after conventional or CO2 laser surgery. Laser bonding application in neurosurgery is proposed for the treatment of dural defects being the Cerebro Spinal Fluid leaks still a major issue. Vocal folds and dura mater were harvested from 9-months old porks and used in the experimental sessions within 4 hours after sacrifice. In vocal folds treatment, an IdocyanineGreen-infused chitosan patch was applied onto the anterior commissure, while the dura mater was previously incised and then bonded. A diode laser emitting at 810 nm, equipped with a 600 μm diameter optical fiber was used to weld the patch onto the tissue, by delivering single laser spots to induce local patch/tissue adhesion. The result is an immediate adhesion of the patch to the tissue. Standard histology was performed, in order to study the induced photothermal effect at the bonding sites. This preliminary experimental activity shows the advantages of the proposed technique in respect to standard surgery: simplification of the procedure; decreased foreign-body reaction; reduced inflammatory response; reduced operating times and better handling in depth.
Improved Lung Perfusion After Left Pulmonary Artery Patch Enlargement During the Norwood Operation.
Salehi Ravesh, Mona; Scheewe, Jens; Attmann, Tim; Al Bulushi, Abdullah; Jussli-Melchers, Marka-Jill; Jerosch-Herold, Michael; Gabbert, Dominik D; Wegner, Philip; Kramer, Hans-Heiner; Rickers, Carsten
2018-05-01
Optimal pulmonary perfusion is crucial for a well-functioning Fontan circulation in patients with hypoplastic left heart syndrome (HLHS). To obtain an adequate size of the left pulmonary artery (LPA), patch enlargement is a routine part of the hemi-Fontan procedure in our center. However, LPA patch enlargement at the time of the modified Norwood procedure may have surgical advantages. Therefore, the aim of this study was to evaluate whether anatomic and functional effects of the new approach are superior. A total of 51 consecutive HLHS patients underwent a cardiovascular magnetic resonance imaging study including assessment of LPA anatomy and lung perfusion. The LPA of 20 patients was enlarged during the modified Norwood procedure (group N) and of 31 patients during the hemi-Fontan procedure (group HF). The median indexed cross-sectional area of the LPA in group N was significantly higher than in group HF (49.5 versus 27.9 mm 2 /m 2 , p < 0.0001). The regional pulmonary perfusion as measured by first-pass, contrast-enhanced signal intensity upslope was significantly improved in group N (left side 0.67 s -1 versus 0.40 s -1 , p = 0.002; right side 0.84 s -1 versus 0.52 s -1 , p = 0.01). The total hemi-Fontan bypass and procedure times were significantly shorter in group N (both p < 0.001). These first magnetic resonance imaging data show that HLHS patients after LPA patch enlargement during the modified Norwood procedure have significantly higher LPA cross-sectional areas and show improved lung perfusion and shorter overall procedure time as compared with LPA patching during second stage (hemi-Fontan). Therefore, this promising surgical technique may improve blood flow dynamics of the Fontan circulation in the long run. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.
Inflatable Antenna for CubeSat: Extension of the Previously Developed S-Band Design to the X-Band
NASA Technical Reports Server (NTRS)
Babuscia, Alessandra; Choi, Thomas; Cheung, Kar-Ming; Thangavelautham, Jekan; Ravichandran, Mithun; Chandra, Aman
2015-01-01
The inflatable antenna for CubeSat is a 1 meter antenna reflector designed with one side reflective Mylar, another side clear Mylar with a patch antenna at the focus. The development of this technology responds to the increasing need for more capable communication systems to allow CubeSats to operate autonomously in interplanetary missions. An initial version of the antenna for the S-Band was developed and tested in both anechoic chamber and vacuum chamber. Recent developments in transceivers and amplifiers for CubeSat at X-band motivated the extension from the S-Band to the X-Band. This paper describes the process of extending the design of the antenna to the X-Band focusing on patch antenna redesign, new manufacturing challenges and initial results of experimental tests.
NASA Astrophysics Data System (ADS)
Ke, Yuanyuan; Yu, Yan; Tong, Yan
2018-01-01
Selecting urban ecological patches is of great significance for constructing urban green infrastructure network, protecting urban biodiversity and ecological environment. With the support of GIS technology, a criterion for selecting sources of patches was developed according to existing planning. Then ecological source patches of terrestrial organism, aquatic and amphibious organism were selected in Wuhan city. To increase the connectivity of the ecological patches and achieve greater ecological protection benefits, the green infrastructure networks in Wuhan city were constructed with the minimum path analysis method. Finally, the characteristics of ecological source patches were analyzed with landscape metrics, and ecological protection importance degree of ecological source patches were evaluated comprehensively. The results showed that there were 23 important ecological source patches in Wuhan city, among which Sushan Temple Forest Patch, Lu Lake and Shangshe Lake Wetland Patch were the most important in all kinds of patches for ecological protection. This study can provide a scientific basis for the preservation of urban ecological space, the delineation of natural conservation areas and the protection of biological diversity.
Jacobowitz, G R; Kalish, J A; Lee, A M; Adelman, M A; Riles, T S; Landis, R
2001-05-01
To determine whether choice of material used for patch closure following carotid artery endarterectomy (CAE) influences rates of early or late restenosis, stroke, and death, 274 consecutive CAEs were retrospectively reviewed. Saphenous vein (SV) was used in 159 (58.0%) procedures; everted, double-thickness jugular vein (JV) was used in 25 (9.1%); and knitted Dacron (KD) was used in 90 (32.9%). Primary closure was not used in this series. There were four perioperative strokes: two (1.3%) in SV, one (4%) in JV, and one (1.1%) in KD (NS). Follow-up was obtained on 263 (96%) operated arteries (mean 41.5 months). Duplex scan results were available for 236 (89.7%) of these arteries (mean follow-up time 33.7 months). There were three (2%) late strokes in SV and two (2.2%) in KD (NS). In long-term follow-up, one patient (0.7%) in SV and two (2.4%) in KD developed > 80% stenosis (NS). One patient (0.7%) in SV, one (5.3%) in JV, and one (1.2%) in KD had total occlusion of the operated vessel (NS). Three procedures (2.2%) in SV, 1 (5.3%) in JV, and 7 (8.5%) in KD demonstrated moderate stenosis (50-79%) (NS). Three-year follow-up shows that choice of patch material does not affect early or late stroke rate, stroke-related death rate, rate of high-grade (> 80%) restenosis, or rate of total occlusion. There is a higher incidence of moderate stenosis in KD. Although our results and a review of the literature do not indicate that these patients are at increased risk for symptoms or progression of stenosis, they should be followed by duplex scanning to ensure that this is the case.
Wong, Carol W Y; Chung, Patrick H Y; Tam, Paul K H; Wong, Kenneth K Y
2015-12-01
Perforated peptic ulcer (PPU) is a relatively uncommon condition in children. We aim to evaluate and compare the outcomes of laparoscopic omental patch repair versus open repair for PPU in pediatric patients. Children who underwent omental patch repair for PPU from 2004 to 2014 in our hospital were reviewed retrospectively. Patient demographics, perioperative as well as intraoperative details and surgical outcomes, were analyzed. Thirteen patients were identified, and all presented with abdominal pain. The median age of the study group was 14.9years (range 6.3 to 18.4years). Radiological evidence of pneumoperitoneum on erect chest x-ray (CXR) was found only in five patients (38.5%). None of the patients had a known history of peptic ulcer disease. Diagnosis other than PPU was made in five patients preoperatively. Laparoscopic repair was attempted in eight patients with one of them requiring conversion. There was no significant difference in patient demographics when compared with the open repair group. The perforation site was in the duodenum in 11 patients and in the antrum in two patients. The mean size of perforation was larger in the open repair group (p=0.005). Although the operating time was longer in the laparoscopic group (p=0.51), the length of hospital stay was significantly shorter (p=0.048). Only two patient diseases were Helicobacter pylori related. Clinical features of perforated peptic ulcer in children are different from adults. Risk factors are less frequently identified. Laparoscopic omental patch repair is a feasible surgical option and is associated with satisfactory outcomes in pediatric practice. Copyright © 2015 Elsevier Inc. All rights reserved.
Dual Band Metamaterial Antenna For LTE/Bluetooth/WiMAX System.
Hasan, Md Mehedi; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul
2018-01-19
A compact metamaterial inspired antenna operate at LTE, Bluetooth and WiMAX frequency band is introduced in this paper. For the lower band, the design utilizes an outer square metallic strip forcing the patch to radiate as an equivalent magnetic-current loop. For the upper band, another magnetic current loop is created by adding metamaterial structure near the feed line on the patch. The metamaterial inspired antenna dimension of 42 × 32 mm 2 compatible to wireless devices. Finite integration technique based CST Microwave Studio simulator has been used to design and numerical investigation as well as lumped circuit model of the metamaterial antenna is explained with proper mathematical derivation. The achieved measured dual band operation of the conventional antenna are sequentially, 0.561~0.578 GHz, 2.346~2.906 GHz, and 2.91~3.49 GHz, whereas the metamaterial inspired antenna shows dual-band operation from 0.60~0.64 GHz, 2.67~3.40 GHz and 3.61~3.67 GHz, respectively. Therefore, the metamaterial antenna is applicable for LTE and WiMAX applications. Besides, the measured metamaterial antenna gains of 0.15~3.81 dBi and 3.47~3.75 dBi, respectively for the frequency band of 2.67~3.40 GHz and 3.61~3.67 GHz.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weldon, Aimee Jean
2004-07-01
Description – Ph.D Dissertation. North Carolina State University. Raleigh, North Carolina. 135 pp. Abatract - Habitat fragmentation and its associated effects have been blamed for the recent population declines of many Neotropical migratory bird species. Increased predation and parasitism resulting from edge-related effects have been implicated for poor nesting success in many studies, mostly of forest interior species. However, little attention has been devoted to disturbance-dependent birds. In this study, I examine how patch shape and connectivity in fragmented landscapes affects the reproductive success of disturbance-dependent bird species, specifically the Indigo Bunting (Passerina cyanea). I conducted my study in amore » landscape-scale experimental system of similar-area habitat patches that differed in connectivity and in shape. Shapes differed between edgy and rectangular forms, where edgy patches contained 50% more edge than rectangular patches. I tested whether edgy patches function as ecological traps for species with strong edge preferences, by leading them to select dangerous habitats. Indigo Buntings preferentially selected edgy patches over rectangular patches, but experienced significantly lower reproductive success in edgy patches early in the season. Although predation pressure intensified in rectangular patches late in the season, seasonal fecundity was still significantly lower in edgy patches, providing the first empirical evidence that edges can function as ecological traps for Indigo Buntings. A second objective of my study was to evaluate the efficacy of conservation corridors for disturbance-dependent bird species. Conservation corridors have become a popular strategy to preserve biodiversity and promote gene flow in fragmented landscapes, but corridors may also have negative consequences. I tested the hypothesis that corridors can increase nest predation risk in connected patches relative to unconnected patches. Nest predation rates increased significantly in connected patches compared to unconnected rectangular patches, but were similar between connected patches and unconnected edgy patches. This suggests that the increase in predator activity in connected patches is largely attributable to edge effects incurred through the addition of a corridor. This is the first landscape-scale study to experimentally demonstrate the potential negative effects of conservation corridors.« less
NASA Astrophysics Data System (ADS)
Helm, P. Johannes; Reppen, Trond; Heggelund, Paul
2009-02-01
Multi Photon Laser Scanning Microscopy (MPLSM) appears today as one of the most powerful experimental tools in cellular neurophysiology, notably in studies of the functional dynamics of signal processing in single neurons. Simultaneous recording of fluorescence signals at high spatial and temporal resolution and electric signals by means of multi electrode patch clamp techniques have provided new paths for the systematic investigation of neuronal mechanisms. In particular, this approach has opened for direct studies of dendritic signal processing in neurons. We report about a setup optimized for simultaneous electrophysiological multi electrode patch clamp and multi photon laser scanning fluorescence microscopic experiments on brain slices. The microscopic system is based on a modified commercially available confocal scanning laser microscope (CLSM). From a technical and operational point of view, two developments are important: Firstly, in order to reduce the workload for the experimentalist, who in general is forced to concentrate on controlling the electrophysiological parameters during the recordings, a system of shutters has been installed together with dedicated electronic modules protecting the photo detectors against destructive light levels caused by erroneous opening or closing of microscopic light paths by the experimentalist. Secondly, the standard detection unit has been improved by installing the photomultiplier tubes (PMT) in a Peltier cooled thermal box shielding the detector from both room temperature and distortions caused by external electromagnetic fields. The electrophysiological system is based on an industrial standard multi patch clamp unit ergonomically arranged around the microscope stage. The electrophysiological and scanning processes can be time coordinated by standard trigger electronics.
[Amelioration of secondary bare alkali-saline patches in Songnen Plain through inserting cornstalk].
He, Nianpeng; Wu, Ling; Jiang, Shicheng; Zhou, Daowei
2004-06-01
Based on the field experiment on Songnen grassland, a new method was established to ameliorate the secondary bare alkali-saline patches (SAP) through inserting cornstalk. The experiment was rested on the assumption that through inserting cornstalk in the secondary bare alkali-saline patches (SAP) to retain seeds moving over its surface, the necessary seed source could be gained; and these seeds should be able to germinate and survive successfully on the cornstalk itself or in its neighborhood, where should be more fit to grow than other sites in SAP, due to the decomposition of cornstalk and its special role, so that, the aim to restore vegetation of SAP could be achieved at a pretty low cost and rapid speed. The results showed that the seed bank in soil was increased significantly, owing to the inserted cornstalk and its operating processes. The seed number in ameliorated soil was 4020.0 +/- 1773.6 seeds x m(-2), while that in the secondary bare alkali-saline patches (SAP) was only 10.0 +/- 31.6 seeds x m(-2). Although the soil chemical and physical characters in ameliorated zone were improved to some extent, the overall situation of soil was still bad for plant growth, as the pH, soluble saline ion and organic matter were concerned. Most of Chloris virgata grew around or on the cornstalk, the plants around each cornstalk being 3.9 +/- 2.2, and the total being 48.64 +/- 38.72 g x m(-2). Therefore, this method demanded a few resources, and needed simple technology and low cost, which is potentially deserved to popularize.
NASA Astrophysics Data System (ADS)
Hussnain, Zille; Oude Elberink, Sander; Vosselman, George
2016-06-01
In mobile laser scanning systems, the platform's position is measured by GNSS and IMU, which is often not reliable in urban areas. Consequently, derived Mobile Laser Scanning Point Cloud (MLSPC) lacks expected positioning reliability and accuracy. Many of the current solutions are either semi-automatic or unable to achieve pixel level accuracy. We propose an automatic feature extraction method which involves utilizing corresponding aerial images as a reference data set. The proposed method comprise three steps; image feature detection, description and matching between corresponding patches of nadir aerial and MLSPC ortho images. In the data pre-processing step the MLSPC is patch-wise cropped and converted to ortho images. Furthermore, each aerial image patch covering the area of the corresponding MLSPC patch is also cropped from the aerial image. For feature detection, we implemented an adaptive variant of Harris-operator to automatically detect corner feature points on the vertices of road markings. In feature description phase, we used the LATCH binary descriptor, which is robust to data from different sensors. For descriptor matching, we developed an outlier filtering technique, which exploits the arrangements of relative Euclidean-distances and angles between corresponding sets of feature points. We found that the positioning accuracy of the computed correspondence has achieved the pixel level accuracy, where the image resolution is 12cm. Furthermore, the developed approach is reliable when enough road markings are available in the data sets. We conclude that, in urban areas, the developed approach can reliably extract features necessary to improve the MLSPC accuracy to pixel level.
Automated Electrophysiology Makes the Pace for Cardiac Ion Channel Safety Screening
Möller, Clemens; Witchel, Harry
2011-01-01
The field of automated patch-clamp electrophysiology has emerged from the tension between the pharmaceutical industry’s need for high-throughput compound screening versus its need to be conservative due to regulatory requirements. On the one hand, hERG channel screening was increasingly requested for new chemical entities, as the correlation between blockade of the ion channel coded by hERG and torsades de pointes cardiac arrhythmia gained increasing attention. On the other hand, manual patch-clamping, typically quoted as the “gold-standard” for understanding ion channel function and modulation, was far too slow (and, consequently, too expensive) for keeping pace with the numbers of compounds submitted for hERG channel investigations from pharmaceutical R&D departments. In consequence it became more common for some pharmaceutical companies to outsource safety pharmacological investigations, with a focus on hERG channel interactions. This outsourcing has allowed those pharmaceutical companies to build up operational flexibility and greater independence from internal resources, and allowed them to obtain access to the latest technological developments that emerged in automated patch-clamp electrophysiology – much of which arose in specialized biotech companies. Assays for nearly all major cardiac ion channels are now available by automated patch-clamping using heterologous expression systems, and recently, automated action potential recordings from stem-cell derived cardiomyocytes have been demonstrated. Today, most of the large pharmaceutical companies have acquired automated electrophysiology robots and have established various automated cardiac ion channel safety screening assays on these, in addition to outsourcing parts of their needs for safety screening. PMID:22131974
Robles, Hugo; Ciudad, Carlos
2012-04-01
Despite extensive research on the effects of habitat fragmentation, the ecological mechanisms underlying colonization and extinction processes are poorly known, but knowledge of these mechanisms is essential to understanding the distribution and persistence of populations in fragmented habitats. We examined these mechanisms through multiseason occupancy models that elucidated patch-occupancy dynamics of Middle Spotted Woodpeckers (Dendrocopos medius) in northwestern Spain. The number of occupied patches was relatively stable from 2000 to 2010 (15-24% of 101 patches occupied every year) because extinction was balanced by recolonization. Larger and higher quality patches (i.e., higher density of oaks >37 cm dbh [diameter at breast height]) were more likely to be occupied. Habitat quality (i.e., density of large oaks) explained more variation in patch colonization and extinction than did patch size and connectivity, which were both weakly associated with probabilities of turnover. Patches of higher quality were more likely to be colonized than patches of lower quality. Populations in high-quality patches were less likely to become extinct. In addition, extinction in a patch was strongly associated with local population size but not with patch size, which means the latter may not be a good surrogate of population size in assessments of extinction probability. Our results suggest that habitat quality may be a primary driver of patch-occupancy dynamics and may increase the accuracy of models of population survival. We encourage comparisons of competing models that assess occupancy, colonization, and extinction probabilities in a single analytical framework (e.g., dynamic occupancy models) so as to shed light on the association of habitat quality and patch geometry with colonization and extinction processes in different settings and species. ©2012 Society for Conservation Biology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Orrock, John, L.; Curler, Gregory, R.; Danielson, Brent, J.
2011-09-14
The size, shape, and isolation of habitat patches can affect organism behavior and population dynamics, but little is known about the relative role of shape and connectivity in affecting ecological communities at large spatial scales. Using six sampling sessions from July 2001 until August 2002, we collected 33,685 arthropods throughout seven 12-ha experimental landscapes consisting of clear-cut patches surrounded by a matrix of mature pine forest. Patches were explicitly designed to manipulate connectivity (via habitat corridors) independently of area and edge effects. We found that patch shape, rather than connectivity, affected ground-dwelling arthropod richness and beta diversity (i.e. turnover ofmore » genera among patches). Arthropod communities contained fewer genera and exhibited less turnover in high-edge connected and high-edge unconnected patches relative to low-edge unconnected patches of similar area. Connectivity, rather than patch shape, affected the evenness of ground-dwelling arthropod communities; regardless of patch shape, high-edge connected patches had lower evenness than low- or high-edge unconnected patches. Among the most abundant arthropod orders, increased richness in low-edge unconnected patches was largely due to increased richness of Coleoptera, whereas Hymenoptera played an important role in the lower evenness in connected patches and patterns of turnover. These findings suggest that anthropogenic habitat alteration can have distinct effects on ground-dwelling arthropod communities that arise due to changes in shape and connectivity. Moreover, this work suggests that corridors, which are common conservation tools that change both patch shape and connectivity, can have multiple effects on arthropod communities via different mechanisms, and each effect may alter components of community structure.« less
Wang, Yong-Jian; Shi, Xue-Ping; Meng, Xue-Feng; Wu, Xiao-Jing; Luo, Fang-Li; Yu, Fei-Hai
2016-01-01
Spatial heterogeneity in two co-variable resources such as light and water availability is common and can affect the growth of clonal plants. Several studies have tested effects of spatial heterogeneity in the supply of a single resource on competitive interactions of plants, but none has examined those of heterogeneous distribution of two co-variable resources. In a greenhouse experiment, we grew one (without intraspecific competition) or nine isolated ramets (with competition) of a rhizomatous herb Iris japonica under a homogeneous environment and four heterogeneous environments differing in patch arrangement (reciprocal and parallel patchiness of light and soil water) and patch scale (large and small patches of light and water). Intraspecific competition significantly decreased the growth of I. japonica, but at the whole container level there were no significant interaction effects of competition by spatial heterogeneity or significant effect of heterogeneity on competitive intensity. Irrespective of competition, the growth of I. japonica in the high and the low water patches did not differ significantly in the homogeneous treatments, but it was significantly larger in the high than in the low water patches in the heterogeneous treatments with large patches. For the heterogeneous treatments with small patches, the growth of I. japonica was significantly larger in the high than in the low water patches in the presence of competition, but such an effect was not significant in the absence of competition. Furthermore, patch arrangement and patch scale significantly affected competitive intensity at the patch level. Therefore, spatial heterogeneity in light and water supply can alter intraspecific competition at the patch level and such effects depend on patch arrangement and patch scale. PMID:27375630
Wang, Yong-Jian; Shi, Xue-Ping; Meng, Xue-Feng; Wu, Xiao-Jing; Luo, Fang-Li; Yu, Fei-Hai
2016-01-01
Spatial heterogeneity in two co-variable resources such as light and water availability is common and can affect the growth of clonal plants. Several studies have tested effects of spatial heterogeneity in the supply of a single resource on competitive interactions of plants, but none has examined those of heterogeneous distribution of two co-variable resources. In a greenhouse experiment, we grew one (without intraspecific competition) or nine isolated ramets (with competition) of a rhizomatous herb Iris japonica under a homogeneous environment and four heterogeneous environments differing in patch arrangement (reciprocal and parallel patchiness of light and soil water) and patch scale (large and small patches of light and water). Intraspecific competition significantly decreased the growth of I. japonica, but at the whole container level there were no significant interaction effects of competition by spatial heterogeneity or significant effect of heterogeneity on competitive intensity. Irrespective of competition, the growth of I. japonica in the high and the low water patches did not differ significantly in the homogeneous treatments, but it was significantly larger in the high than in the low water patches in the heterogeneous treatments with large patches. For the heterogeneous treatments with small patches, the growth of I. japonica was significantly larger in the high than in the low water patches in the presence of competition, but such an effect was not significant in the absence of competition. Furthermore, patch arrangement and patch scale significantly affected competitive intensity at the patch level. Therefore, spatial heterogeneity in light and water supply can alter intraspecific competition at the patch level and such effects depend on patch arrangement and patch scale.
PATCH image processor user's manual
NASA Technical Reports Server (NTRS)
Nieves, M. J. (Principal Investigator)
1980-01-01
The patch image processor extracts patches in various size (32 x 32, 64 x 64, 128 x 128, and 256 x 256 pixels) from full frame LANDSAT imagery data. With the patches that are extracted, a patch image mosaic is created in the image processing system, IMDACS, format.
Grez, A A; González, R H
1995-09-01
The resource concentration hypothesis (Root 1973) predicts that specialist herbivorous insects should be more abundant in large patches of host plants, because the insects are more likely to find and stay longer in those patches. Between August 1989 and January 1990 we experimentally tested Root's hypothesis by analyzing the numerical response of four species of herbivorous insects associated with patches of 4, 16, 64 and 225 cabbage plants, Brassica oleracea var. capitata. In addition, we studied the colonization of patches by adults of Plutella xylostella (L.) (Lepidoptera: Plutellidae), and the migration of their larvae in patches of different sizes. No herbivorous insect densities differed significantly with patch size. Adults of P. xylostella colonized all kind of patches equally. Larvae did not migrate between patches, and their disappearance rate did not differ between patches. The resource concentration hypothesis is organism-dependent, being a function of the adult and juvenile herbivore dispersal behavior in relation to the spatial scale of patchiness.
Shazman, Shula; Celniker, Gershon; Haber, Omer; Glaser, Fabian; Mandel-Gutfreund, Yael
2007-07-01
Positively charged electrostatic patches on protein surfaces are usually indicative of nucleic acid binding interfaces. Interestingly, many proteins which are not involved in nucleic acid binding possess large positive patches on their surface as well. In some cases, the positive patches on the protein are related to other functional properties of the protein family. PatchFinderPlus (PFplus) http://pfp.technion.ac.il is a web-based tool for extracting and displaying continuous electrostatic positive patches on protein surfaces. The input required for PFplus is either a four letter PDB code or a protein coordinate file in PDB format, provided by the user. PFplus computes the continuum electrostatics potential and extracts the largest positive patch for each protein chain in the PDB file. The server provides an output file in PDB format including a list of the patch residues. In addition, the largest positive patch is displayed on the server by a graphical viewer (Jmol), using a simple color coding.
Shazman, Shula; Celniker, Gershon; Haber, Omer; Glaser, Fabian; Mandel-Gutfreund, Yael
2007-01-01
Positively charged electrostatic patches on protein surfaces are usually indicative of nucleic acid binding interfaces. Interestingly, many proteins which are not involved in nucleic acid binding possess large positive patches on their surface as well. In some cases, the positive patches on the protein are related to other functional properties of the protein family. PatchFinderPlus (PFplus) http://pfp.technion.ac.il is a web-based tool for extracting and displaying continuous electrostatic positive patches on protein surfaces. The input required for PFplus is either a four letter PDB code or a protein coordinate file in PDB format, provided by the user. PFplus computes the continuum electrostatics potential and extracts the largest positive patch for each protein chain in the PDB file. The server provides an output file in PDB format including a list of the patch residues. In addition, the largest positive patch is displayed on the server by a graphical viewer (Jmol), using a simple color coding. PMID:17537808
Periodic creation of polar cap patches from auroral transients in the cusp
NASA Astrophysics Data System (ADS)
Hosokawa, K.; Taguchi, S.; Ogawa, Y.
2016-06-01
On 24 November 2012, an interval of polar cap patches was identified by an all-sky airglow imager located near the dayside cusp. During the interval, the successive appearance of poleward moving auroral forms (PMAFs) was detected, which are known to represent ionospheric manifestations of pulsed magnetic reconnections at the dayside magnetopause. All of the patches observed during the interval appeared from these transient auroral features (i.e., there was a one-to-one correspondence between PMAFs and newly created baby patches). This fact strongly suggests that patches can be directly and seamlessly created from a series of PMAFs. The optical intensities of the baby patches were 100-150 R, which is slightly lower than typical patch luminosity on the nightside and may imply that PMAF-induced patches are generally low density. The generation of such patches could be explained by impact ionization due to soft particle precipitation into PMAFs traces. In spite of the faint signature of the baby patches, two coherent HF radars of the SuperDARN network observed backscatter echoes in the central polar cap, which represented signatures of plasma irregularities associated with the baby patches. These indicate that patches created from PMAFs have the potential to affect the satellite communications environment in the central polar cap region.
de Jong, Peter W; Hemerik, Lia; Gort, Gerrit; van Alphen, Jacques J M
2011-01-01
Females of the larval parasitoid of Drosophila, Asobara citri, from sub-Saharan Africa, defend patches with hosts by fighting and chasing conspecific females upon encounter. Females of the closely related, palearctic species Asobara tabida do not defend patches and often search simultaneously in the same patch. The effect of patch defence by A. citri females on their distribution in a multi-patch environment was investigated, and their distributions were compared with those of A. tabida. For both species 20 females were released from two release-points in replicate experiments. Females of A. citri quickly reached a regular distribution across 16 patches, with a small variance/mean ratio per patch. Conversely, A. tabida females initially showed a clumped distribution, and after gradual dispersion, a more Poisson-like distribution across patches resulted (variance/mean ratio was closer to 1 and higher than for A. citri). The dispersion of A. tabida was most probably an effect of exploitation: these parasitoids increasingly made shorter visits to already exploited patches. We briefly discuss hypotheses on the adaptive significance of patch defence behaviour or its absence in the light of differences in the natural history of both parasitoid species, notably the spatial distribution of their hosts.
Effect of patch borders on coercivity in amorphous rare earth-transition metal thin films
NASA Technical Reports Server (NTRS)
Patterson, G.; Fu, H.; Giles, R. C.; Mansuripur, M.
1991-01-01
The coercivity at the micron scale is a very important property of magneto-optical media. It is a key factor that determines the magnetic domain wall movement and domain reversal. How the coercivity is influenced by a special type of patch borders is discussed. Patch formation is a general phenomenon in growth processes of amorphous rare earth transition metal thin films. Different patches may stem from different seeds and the patch borders are formed when they merge. Though little is known about the exact properties of the borders, we may expect that the exchange interaction at the patch border is weaker than that within a patch, since there is usually a spatial gap between two patches. Computer simulations were performed on a 2-D hexagonal lattice consisting of 37 complete patches with random shape and size. From the series of simulations we may conclude that the domain in the patch with borders of 30 percent exchange strength can expand most easily to the whole lattice, because the exchange strength can expand most easily to the whole lattice, because the exchange strength of the border is not too high to prevent the domain from growing within the patch and it is not too low to prevent the domain from expanding beyond the patch.
Departure Mechanisms for Host Search on High-Density Patches by the Meteorus pulchricornis
Sheng, Sheng; Feng, Sufang; Meng, Ling; Li, Baoping
2014-01-01
Abstract Less attention has been paid to the parasitoid–host system in which the host occurs in considerably high density with a hierarchical patch structure in studies on time allocation strategies of parasitoids. This study used the parasitoid Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) and the Oriental leafworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) as the parasitoids–host model system to investigate patch-leaving mechanisms as affected by the high-host density, hierarchical patch structure, and foraging behaviors on both former and current patches. The results showed that three out of eight covariates tested had significant effects on the patch-leaving tendency, including the host density, ovipositor insertion, and host rejection on the current patch. The parasitoid paid more visits to the patch with high-density hosts. While the patch with higher host densities decreased the leaving tendency, the spatial distribution of hosts examined had no effect on the leaving tendency. Both oviposition and host rejection decreased the patch-leaving tendency. The variables associated with the former patch, such as the host density and number of ovipositor insertions, however, did not have an effect on the leaving tendency. Our study suggested that M. pulchricornis females may use an incremental mechanism to exploit high-density patches to the fullest. PMID:25502040
Prasertvit, Piyatida; Chareonyingwattana, Angkana; Wattanakrai, Penpun
2017-12-01
Antiretroviral drug hypersensitivity in HIV patients is common. Publications have shown that Abacavir (ABC) patch testing is useful in confirming ABC hypersensitivity in 24-50% of cases with a 100% sensitivity of HLA-B*5701 in patch test positive cases. However, Nevirapine (NVP) patch testing has not been reported. (1) To evaluate the usefulness and safety of NVP patch testing in Thai HIV patients with NVP hypersensitivity. (2) To assess the correlation of positive patch tests with HLA-B*3505. Patients were classified into two groups: (1) study group of 20 HIV NVP hypersensitivity patients and (2) control group of 15 volunteers without NVP hypersensitivity. Both groups were patch tested with purified and commercialized form of NVP in various vehicles. Two HIV patients with NVP hypersensitivity were patch test positive. All controls tested negative. Three HIV patients were positive for HLA-B*3505 and the two patients with positive patch testing were both HLA-B*3505 positive. NVP patch testing in Thai HIV patients is safe and can be used to help confirm the association between NVP and hypersensitivity skin reactions. NVP patch test results significantly correlated with HLA-B*3505. The sensitivity of HLA-B*3505 for positive patch test was 100%. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Testing in Service-Oriented Environments
2010-03-01
software releases (versions, service packs, vulnerability patches) for one com- mon ESB during the 13-month period from January 1, 2008 through...impact on quality of service : Unlike traditional software compo- nents, a single instance of a web service can be used by multiple consumers. Since the...distributed, with heterogeneous hardware and software (SOA infrastructure, services , operating systems, and databases). Because of cost and security, it
Cybersecurity Workforce Development and the Protection of Critical Infrastructure
2017-03-31
communicat ions products, and limited travel for site visits and conferencing. The CSCC contains a developed web-based coordination site, computer ...the CSCC. The Best Practices Ana~yst position maintains a lisr of best practices, computer related patches. and standard operating procedures (SOP...involved in conducting vulnerability assessments of computer networks. To adequately exercise and experiment with industry standard software, it was
1994-07-20
The STS-64 patch depicts the Space Shuttle Discovery in a payload-bay-to-Earth attitude with its primary payload, Lidar In-Space Technology Experiment (LITE-1) operating in support of Mission to Planet Earth. LITE-1 is a lidar system that uses a three-wavelength laser, symbolized by the three gold rays emanating from the star in the payload bay that form part of the astronaut symbol. The major objective of the LITE-1 is to gather data about the Earth's troposphere and stratosphere, represented by the clouds and dual-colored Earth limb. A secondary payload on STS-64 is the free-flier SPARTAN 201 satellite shown on the Remote Manipulator System (RMS) arm post-retrieval. The RMS also operated another payload, Shuttle Plume Impingement Flight Experiment (SPIFEX). A newly tested extravehicular activity (EVA) maneuvering device, Simplified Aid for EVA Rescue (SAFER), represented symbolically by the two small nozzles on the backpacks of the two untethered EVA crew men. The names of the crew members encircle the patch: Astronauts Richard N. Richards, L. Blaine Hammond, Jr., Jerry M. Linenger, Susan J. Helms, Carl J. Meade and Mark C. Lee. The gold or silver stars by each name represent that person's parent service.
Qi, Shan-Shan; Wang, Wen-Hui; Gao, Qiang; Xu, Xiao-Hong; He, Wan-Hong; Zhaxi, Ying-Pai; Tai, Li-Feng
2011-08-01
The distribution, size, and appearance of Peyer's patches vary according to species. In order to determine the anatomical characteristics of Peyer's patches in small intestine of Bactrian camel, and age-related changes in the number of Peyer's patches, 40 Bactrian camels of the following four age groups were studied: young (0.5-2 years), pubertal (3-5 years), middle-aged (6-16 years), and old (17-20 years). The exact number of Peyer's patches was recorded, and the appearance of Peyer's patches was described in detail. The results indicated that Peyer's patches of Bactrian camels not only have a particular anatomical location and distinct appearance but also change with age. They were distributed in the whole small intestine and there were four distinct types of Peyer's patches: nodular, faviform, cup-shaped, and cystic form Peyer's patches. However, the nodular and cystic form Peyer's patches are specific to Bactrian camel, which have not been found in other animals including Dromedary camel. In addition, the distribution density of Peyer's patches in ileum was the maximum, then was jejunum and duodenum. Further statistical analysis showed that the number of Peyer's patches was altered with age. The number peaked in 5-year-old camels and declined subsequently with age. However, there was little change in the size of Peyer's patches in different age groups; no age-related macroscopic variations in the shape or size of the Peyer's patches were found. Results obtained from this study provide the basic information to further study on the gastrointestinal mucosal immunity of Bactrian camel.
Closure technique after carotid endarterectomy influences local hemodynamics.
Harrison, Gareth J; How, Thien V; Poole, Robert J; Brennan, John A; Naik, Jagjeeth B; Vallabhaneni, S Rao; Fisher, Robert K
2014-08-01
Meta-analysis supports patch angioplasty after carotid endarterectomy (CEA); however, studies indicate considerable variation in practice. The hemodynamic effect of a patch is unclear and this study attempted to elucidate this and guide patch width selection. Four groups were selected: healthy volunteers and patients undergoing CEA with primary closure, trimmed patch (5 mm), or 8-mm patch angioplasty. Computer-generated three-dimensional models of carotid bifurcations were produced from transverse ultrasound images recorded at 1-mm intervals. Rapid prototyping generated models for flow visualization studies. Computational fluid dynamic studies were performed for each model and validated by flow visualization. Mean wall shear stress (WSS) and oscillatory shear index (OSI) maps were created for each model using pulsatile inflow at 300 mL/min. WSS of <0.4 Pa and OSI >0.3 were considered pathological, predisposing to accretion of intimal hyperplasia. The resultant WSS and OSI maps were compared. The four groups comprised 8 normal carotid arteries, 6 primary closures, 6 trimmed patches, and seven 8-mm patches. Flow visualization identified flow separation and recirculation at the bifurcation increased with a patch and was related to the patch width. Computational fluid dynamic identified that primary closure had the fewest areas of low WSS or elevated OSI but did have mild common carotid artery stenoses at the proximal arteriotomy that caused turbulence. Trimmed patches had more regions of abnormal WSS and OSI at the bifurcation, but 8-mm patches had the largest areas of deleteriously low WSS and high OSI. Qualitative comparison among the four groups confirmed that incorporation of a patch increased areas of low WSS and high OSI at the bifurcation and that this was related to patch width. Closure technique after CEA influences the hemodynamic profile. Patching does not appear to generate favorable flow dynamics. However, a trimmed 5-mm patch may offer hemodynamic benefits over an 8-mm patch and may be the preferred option. Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.
Laparoscopic Repair of Perforated Peptic Ulcer: Outcome and Associated Morbidity and Mortality
Alemrajabi, Mahdi; Safari, Saeed; Tizmaghz, Adnan; Alemrajabi, Fatemeh; Shabestanipour, Ghazaal
2016-01-01
Introduction The mainstay of treatment for perforated peptic ulcer is Omental patch closure. With the advent of laparoscopic surgery, this approach is being used for the treatment of perforated peptic ulcer. The aim of this study was to evaluate the outcome of laparoscopy in Firoozgar general hospital over a period of 18 months. The outcome of the laparoscopic approach and the associated morbidity and mortality, operation time, conversion rate and hospital stay were assessed. Methods A prospective analysis of 29 consecutive patients (mean age 37.5 years; 23 men) with perforated peptic ulcers and who had undergone laparoscopic surgery was carried over a period of 18 months from March 2014 until September 2015. Pre-operative, intra-operative, and post-operative clinical data were collectively analyzed by SPSS 19 for Windows. Results Seventeen patients had a history of cigarette smoking, 11 patients had a history of opium consumption, 19 were chronic NSAID users, 26 had Helicobacter pylori infections, and six had a co-morbid condition. Previous surgical history included laparotomy for pancreatic cancer in two patients, for sigmoid colon cancer in one patient, and for acute appendicitis in four patients. The average operating time for all cases was 47.5 + 20 min. The mean lag time between onset of symptoms and surgery was 20.4 hours. All patients underwent laparoscopic closure of the perforation with Omental patch closure. No morbidity was observed, and none of the patients needed conversion to open surgery. One patient died after 11 months of follow-up due to the progression of underlying pancreatic cancer. The mean postoperative hospital stay was 4.2 days. Conclusions The results of the laparoscopic approach for perforated peptic ulcer were promising, with no conversion to open surgery, no morbidity, and mortality. PMID:27504170
Desai, Sameer N; Badiger, Santhoshi V; Tokur, Shreesha B; Naik, Prashanth A
2017-03-01
Transdermal buprenorphine, which is used in chronic pain management, has rarely been studied for use in acute pain management. The aim of this study was to compare the safety and efficacy of transdermal buprenorphine patch to oral tramadol for post-operative analgesia, following proximal femur surgeries. Fifty adult patients undergoing surgery for hip fracture under spinal anaesthesia were included in this study. One group (Group TDB) received transdermal buprenorphine 10 mcg/h patch applied a day before the surgery and other group received oral tramadol 50 mg three times a day for analgesia (Group OT). They were allowed to take diclofenac and paracetamol tablets for rescue analgesia. Pain scores at rest, on movement, rescue analgesic requirement and side effects were compared between the groups over 7 days. Chi-square and independent sample t -test were used for categorical and continuous variables, respectively. Resting pain scores and pain on movement were significantly lower in TDB Group on all 7 days starting from 24 h post-operatively. Rescue analgesic requirement was significantly lower in TDB Group compared to OT Group. All the patients needed rescue analgesic in OT Group whereas 68% of the patients needed the same in TDB Group. Incidence of vomiting was less and satisfaction scores were much higher in TDB Group as compared to OT Group (79% vs. 66%, P < 0.001). Transdermal buprenorphine can be safely used for post-operative analgesia and is more efficacious in reducing post-operative pain after 24 hours, with fewer side effects when compared to oral tramadol.
Shelat, Vishal G.; Ahmed, Saleem; Chia, Clement L. K.; Cheah, Yee Lee
2015-01-01
Application of minimal access surgery in acute care surgery is limited due to various reasons. Laparoscopic omental patch repair (LOPR) for perforated peptic ulcer (PPU) surgery is safe and feasible but not widely implemented. We report our early experience of LOPR with emphasis on strict selection criteria. This is a descriptive study of all patients operated on for PPU at academic university-affiliated institutes from December 2010 to February 2012. All the patients who were operated on for LOPR were included as the study population and their records were studied. Perioperative outcomes, Boey score, Mannheim Peritonitis Index (MPI), and physiologic and operative severity scores for enumeration of mortality and morbidity (POSSUM) scores were calculated. All the data were tabulated in a Microsoft Excel spreadsheet and analyzed using Stata Version 8.x. (StataCorp, College Station, TX, USA). Fourteen patients had LOPR out of a total of 45 patients operated for the PPU. Mean age was 46 years (range 22−87 years). Twelve patients (86%) had a Boey score of 0 and all patients had MPI < 21 (mean MPI = 14). The predicted POSSUM morbidity and mortality were 36% and 7%, respectively. Mean ulcer size was 5 mm (range 2−10 mm), mean operating time was 100 minutes (range 70−123 minutes) and mean length of hospital stay was 4 days (range 3−6 days). There was no morbidity or mortality pertaining to LOPR. LOPR should be offered by acute care surgical teams when local expertise is available. This can optimize patient outcomes when strict selection criteria are applied. PMID:25692444
Laparoscopic Repair of Perforated Peptic Ulcer: Outcome and Associated Morbidity and Mortality.
Alemrajabi, Mahdi; Safari, Saeed; Tizmaghz, Adnan; Alemrajabi, Fatemeh; Shabestanipour, Ghazaal
2016-06-01
The mainstay of treatment for perforated peptic ulcer is Omental patch closure. With the advent of laparoscopic surgery, this approach is being used for the treatment of perforated peptic ulcer. The aim of this study was to evaluate the outcome of laparoscopy in Firoozgar general hospital over a period of 18 months. The outcome of the laparoscopic approach and the associated morbidity and mortality, operation time, conversion rate and hospital stay were assessed. A prospective analysis of 29 consecutive patients (mean age 37.5 years; 23 men) with perforated peptic ulcers and who had undergone laparoscopic surgery was carried over a period of 18 months from March 2014 until September 2015. Pre-operative, intra-operative, and post-operative clinical data were collectively analyzed by SPSS 19 for Windows. Seventeen patients had a history of cigarette smoking, 11 patients had a history of opium consumption, 19 were chronic NSAID users, 26 had Helicobacter pylori infections, and six had a co-morbid condition. Previous surgical history included laparotomy for pancreatic cancer in two patients, for sigmoid colon cancer in one patient, and for acute appendicitis in four patients. The average operating time for all cases was 47.5 + 20 min. The mean lag time between onset of symptoms and surgery was 20.4 hours. All patients underwent laparoscopic closure of the perforation with Omental patch closure. No morbidity was observed, and none of the patients needed conversion to open surgery. One patient died after 11 months of follow-up due to the progression of underlying pancreatic cancer. The mean postoperative hospital stay was 4.2 days. The results of the laparoscopic approach for perforated peptic ulcer were promising, with no conversion to open surgery, no morbidity, and mortality.
A study of tensile residual strength of composite laminates under different patch-repaired series
NASA Astrophysics Data System (ADS)
Ding, M. H.; zhan, S.; Tang, Y. H.; Wang, L.; Ma, D. Q.; Wang, R. G.
2017-09-01
The tensile behavior of composite laminate structures repaired by bonding external patches was studied in the paper. Two different types of patches including wedge patches and inverted wedge patches were used and failure mechanisms, failure load and strength predictions were studied. A convenient and fast method of building 2-D finite element modeling (FEM) of laminate structure repaired was proposed and the strength of repaired laminate structures was calculated by FEM. The results showed that more than 80% tensile strength of the undamaged laminate could be recovered by bonding patch repairs. Moreover, the results indicated that the strength of inverted wedge patches repair were higher than that of wedge patches repair. FEM simulation results indicated that high stress concentration was found along the edges of invert patches and the most weakness part located in the adhesive bondline. FEM analysis results showed that the strength predicted matched well with the test strength.
GIS-based approach for quantifying landscape connectivity of Javan Hawk-Eagle habitat
NASA Astrophysics Data System (ADS)
Nurfatimah, C.; Syartinilia; Mulyani, Y. A.
2018-05-01
Javan Hawk-Eagle (Nisaetus bartelsi; JHE) is a law-protected endemic raptor which currently faced the decreased in number and size of habitat patches that will lead to patch isolation and species extinction. This study assessed the degree of connectivity between remnant habitat patches in central part of Java by utilizing Conefor Sensinode software as an additional tool for ArcGIS. The connectivity index was determined by three fractions which are infra, flux and connector. Using connectivity indices successfully identified 4 patches as core habitat, 9 patches as stepping-stone habitat and 6 patches as isolated habitat were derived from those connectivity indices. Those patches then being validated with land cover map derived from Landsat 8 of August 2014. 36% of core habitat covered by natural forest, meanwhile stepping stone habitat has 55% natural forest and isolated habitat covered by 59% natural forest. Isolated patches were caused by zero connectivity (PCcon = 0) and the patch size which too small to support viable JHE population. Yet, the condition of natural forest and the surrounding matrix landscape in isolated patches actually support the habitat need. Thus, it is very important to conduct the right conservation management system based on the condition of each patches.
The art and science of mission patches and their origins in society
NASA Astrophysics Data System (ADS)
Brumfitt, A.; Thompson, L. A.; Raitt, D.
2008-06-01
Space exploration utilizes some of the latest and highest technology available to human kind; synonymous with space exploration is the mission patch. This specialized art form popularizes the exploration of space with millions of mission patches sold around the world. Space tourism and education centres like the Kennedy Space Centre rely heavily on each space shuttle launch to support their merchandising of mission patches, from the traditional sew on badge to T shirts. Do mission patches tell a story? Are they Art? What is the origin and role of this art form in society? The art form of space mission patches combines the 21st century relevance with heraldic origins predating the ninth century. The space mission patch is designed by the astronauts themselves if it is a manned mission. As an education tool teachers and educators use the space mission patch to engage their students in the excitement of space exploration, the mission patch design is utilized as an education tool in literature, science and art. The space mission patch is a particularly powerful message medium. This paper looks at the origins of the space mission patch, its relevance to art and its impact on society.
Invertebrate community response to a shifting mosaic of habitat
Engle, David M.; Fuhlendorf, S.D.; Roper, A.; Leslie, David M.
2008-01-01
Grazing management has focused largely on promoting vegetation homogeneity through uniform distribution of grazing to minimize area in a pasture that is either heavily disturbed or undisturbed. An alternative management model that couples grazing and fire (i.e., patch burning) to promote heterogeneity argues that grazing and fire interact through a series of positive and negative feedbacks to cause a shifting mosaic of vegetation composition and structure across the landscape. We compared patch burning with traditional homogeneity-based management in tallgrass prairie to determine the influence of the two treatments on the aboveground invertebrate community. Patch burning resulted in a temporal flush of invertebrate biomass in patches transitional between unburned and patches burned in the current year. Total invertebrate mass was about 50% greater in these transitional patches within patch-burned pastures as compared to pastures under traditional, homogeneity-based management. Moreover, the mosaic of patches in patch-burned pastures contained a wider range of invertebrate biomass and greater abundance of some invertebrate orders than did the traditionally managed pastures. Patch burning provides habitat that meets requirements for a broad range of invertebrate species, suggesting the potential for patch burning to benefit other native animal assemblages in the food chain.
The effect of travel loss on evolutionarily stable distributions of populations in space.
Deangelis, Donald L; Wolkowicz, Gail S K; Lou, Yuan; Jiang, Yuexin; Novak, Mark; Svanbäck, Richard; Araújo, Márcio S; Jo, Youngseung; Cleary, Erin A
2011-07-01
A key assumption of the ideal free distribution (IFD) is that there are no costs in moving between habitat patches. However, because many populations exhibit more or less continuous population movement between patches and traveling cost is a frequent factor, it is important to determine the effects of costs on expected population movement patterns and spatial distributions. We consider a food chain (tritrophic or bitrophic) in which one species moves between patches, with energy cost or mortality risk in movement. In the two-patch case, assuming forced movement in one direction, an evolutionarily stable strategy requires bidirectional movement, even if costs during movement are high. In the N-patch case, assuming that at least one patch is linked bidirectionally to all other patches, optimal movement rates can lead to source-sink dynamics where patches with negative growth rates are maintained by other patches with positive growth rates. As well, dispersal between patches is not balanced (even in the two-patch case), leading to a deviation from the IFD. Our results indicate that cost-associated forced movement can have important consequences for spatial metapopulation dynamics. Relevance to marine reserve design and the study of stream communities subject to drift is discussed.
Hu, Bingjie; Zhu, Xiaolei; Monroe, Lyman; Bures, Mark G; Kihara, Daisuke
2014-08-27
Structure-based computational methods have been widely used in exploring protein-ligand interactions, including predicting the binding ligands of a given protein based on their structural complementarity. Compared to other protein and ligand representations, the advantages of a surface representation include reduced sensitivity to subtle changes in the pocket and ligand conformation and fast search speed. Here we developed a novel method named PL-PatchSurfer (Protein-Ligand PatchSurfer). PL-PatchSurfer represents the protein binding pocket and the ligand molecular surface as a combination of segmented surface patches. Each patch is characterized by its geometrical shape and the electrostatic potential, which are represented using the 3D Zernike descriptor (3DZD). We first tested PL-PatchSurfer on binding ligand prediction and found it outperformed the pocket-similarity based ligand prediction program. We then optimized the search algorithm of PL-PatchSurfer using the PDBbind dataset. Finally, we explored the utility of applying PL-PatchSurfer to a larger and more diverse dataset and showed that PL-PatchSurfer was able to provide a high early enrichment for most of the targets. To the best of our knowledge, PL-PatchSurfer is the first surface patch-based method that treats ligand complementarity at protein binding sites. We believe that using a surface patch approach to better understand protein-ligand interactions has the potential to significantly enhance the design of new ligands for a wide array of drug-targets.
Hu, Bingjie; Zhu, Xiaolei; Monroe, Lyman; Bures, Mark G.; Kihara, Daisuke
2014-01-01
Structure-based computational methods have been widely used in exploring protein-ligand interactions, including predicting the binding ligands of a given protein based on their structural complementarity. Compared to other protein and ligand representations, the advantages of a surface representation include reduced sensitivity to subtle changes in the pocket and ligand conformation and fast search speed. Here we developed a novel method named PL-PatchSurfer (Protein-Ligand PatchSurfer). PL-PatchSurfer represents the protein binding pocket and the ligand molecular surface as a combination of segmented surface patches. Each patch is characterized by its geometrical shape and the electrostatic potential, which are represented using the 3D Zernike descriptor (3DZD). We first tested PL-PatchSurfer on binding ligand prediction and found it outperformed the pocket-similarity based ligand prediction program. We then optimized the search algorithm of PL-PatchSurfer using the PDBbind dataset. Finally, we explored the utility of applying PL-PatchSurfer to a larger and more diverse dataset and showed that PL-PatchSurfer was able to provide a high early enrichment for most of the targets. To the best of our knowledge, PL-PatchSurfer is the first surface patch-based method that treats ligand complementarity at protein binding sites. We believe that using a surface patch approach to better understand protein-ligand interactions has the potential to significantly enhance the design of new ligands for a wide array of drug-targets. PMID:25167137
Zug, Kathryn A; Pham, Anh Khoa; Belsito, Donald V; DeKoven, Joel G; DeLeo, Vincent A; Fowler, Joseph F; Fransway, Anthony F; Maibach, Howard I; Marks, James G; Mathias, C G Toby; Pratt, Melanie D; Sasseville, Denis; Storrs, Frances J; Taylor, James S; Warshaw, Erin M; Zirwas, Matthew J
2014-01-01
Allergic contact dermatitis is common in children. Epicutaneous patch testing is an important tool for identifying responsible allergens. The objective of this study was to provide the patch test results from children (aged ≤18 years) examined by the North American Contact Dermatitis Group from 2005 to 2012. This is a retrospective analysis of children patch-tested with the North American Contact Dermatitis Group 65- or 70-allergen series. Frequencies and counts were compared with previously published data (2001-2004) using χ statistics. A total of 883 children were tested during the study period. A percentage of 62.3% had ≥1 positive patch test and 56.7% had ≥1 relevant positive patch test. Frequencies of positive patch test and relevant positive patch test reaction were highest with nickel sulfate (28.1/25.6), cobalt chloride (12.3/9.1), neomycin sulfate (7.1/6.6), balsam of Peru (5.7/5.5), and lanolin alcohol 50% petrolatum vehicle (5.5/5.1). The ≥1 positive patch test and ≥1 relevant positive patch test in the children did not differ significantly from adults (≥19 years) or from previously tested children (2001-2004). The percentage of clinically relevant positive patch tests for 27 allergens differed significantly between the children and adults. A total of 23.6% of children had a relevant positive reaction to at least 1 supplemental allergen. Differences in positive patch test and relevant positive patch test frequencies between children and adults as well as test periods confirm the importance of reporting periodic updates of patch testing in children to enhance clinicians' vigilance to clinically important allergens.
Aortic valve repair with autologous pericardial patch.
Lausberg, Henning F; Aicher, Diana; Langer, Frank; Schäfers, Hans-Joachim
2006-08-01
Isolated aortic valve repair (AVR) has been gaining increasing interest in recent times. Results of isolated aortic valve repair have been reported to be variable. Various techniques have been utilized. We analyzed our experience with isolated valve repair using autologous pericardial patch plasty and compared the results to an age-matched collective with aortic valve repair without the use of additional material. Between January 1997 and June 2005, pericardial patch plasty of the aortic valve was performed in 42 patients (PATCH). During the same period, 42 patients after AVR without the use of additional material were age matched (NO-PATCH). Mean age in both groups was 52 years with a majority of male patients (PATCH ratio, 3.7:1; NO-PATCH ratio, 5:1). Valve anatomy was similar in both groups. All patients were followed by echocardiography for a cumulative follow-up of 2341 patient months (mean 28+/-23 months). No patient died in the hospital in neither group. The average systolic gradient was 5.9+/-2.2 mmHg in PATCH and 4.8+/-2.1 mmHg in NO-PATCH; p=0.17). Freedom from aortic regurgitation > or = II degrees was 87.8% in PATCH and 95.0% in NO-PATCH after 5 years (p=0.21). Freedom from reoperation was 97.6% in PATCH and 97.4% in NO-PATCH (p=0.96). Aortic regurgitation can be treated effectively by aortic valve repair using pericardial patch plasty. The functional results are satisfactory. With the application of this technique also more complex pathologies of the aortic valve can be addressed adequately thus extending the concept of valve preservation in patients with aortic regurgitation.
Mate choice when males are in patches: optimal strategies and good rules of thumb.
Hutchinson, John M C; Halupka, Konrad
2004-11-07
In standard mate-choice models, females encounter males sequentially and decide whether to inspect the quality of another male or to accept a male already inspected. What changes when males are clumped in patches and there is a significant cost to travel between patches? We use stochastic dynamic programming to derive optimum strategies under various assumptions. With zero costs to returning to a male in the current patch, the optimal strategy accepts males above a quality threshold which is constant whenever one or more males in the patch remain uninspected; this threshold drops when inspecting the last male in the patch, so returns may occur only then and are never to a male in a previously inspected patch. With non-zero within-patch return costs, such a two-threshold rule still performs extremely well, but a more gradual decline in acceptance threshold is optimal. Inability to return at all need not decrease performance by much. The acceptance threshold should also decline if it gets harder to discover the last males in a patch. Optimal strategies become more complex when mean male quality varies systematically between patches or years, and females estimate this in a Bayesian manner through inspecting male qualities. It can then be optimal to switch patch before inspecting all males on a patch, or, exceptionally, to return to an earlier patch. We compare performance of various rules of thumb in these environments and in ones without a patch structure. A two-threshold rule performs excellently, as do various simplifications of it. The best-of-N rule outperforms threshold rules only in non-patchy environments with between-year quality variation. The cutoff rule performs poorly.
Departure mechanisms for host search on high-density patches by the Meteorus pulchricornis.
Sheng, Sheng; Feng, Sufang; Meng, Ling; Li, Baoping
2014-01-01
Less attention has been paid to the parasitoid-host system in which the host occurs in considerably high density with a hierarchical patch structure in studies on time allocation strategies of parasitoids. This study used the parasitoid Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) and the Oriental leafworm, Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae) as the parasitoids-host model system to investigate patch-leaving mechanisms as affected by the high-host density, hierarchical patch structure, and foraging behaviors on both former and current patches. The results showed that three out of eight covariates tested had significant effects on the patch-leaving tendency, including the host density, ovipositor insertion, and host rejection on the current patch. The parasitoid paid more visits to the patch with high-density hosts. While the patch with higher host densities decreased the leaving tendency, the spatial distribution of hosts examined had no effect on the leaving tendency. Both oviposition and host rejection decreased the patch-leaving tendency. The variables associated with the former patch, such as the host density and number of ovipositor insertions, however, did not have an effect on the leaving tendency. Our study suggested that M. pulchricornis females may use an incremental mechanism to exploit high-density patches to the fullest. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.
Scale-dependent feedbacks between patch size and plant reproduction in desert grassland
Svejcar, Lauren N.; Bestelmeyer, Brandon T.; Duniway, Michael C.; James, Darren K.
2015-01-01
Theoretical models suggest that scale-dependent feedbacks between plant reproductive success and plant patch size govern transitions from highly to sparsely vegetated states in drylands, yet there is scant empirical evidence for these mechanisms. Scale-dependent feedback models suggest that an optimal patch size exists for growth and reproduction of plants and that a threshold patch organization exists below which positive feedbacks between vegetation and resources can break down, leading to critical transitions. We examined the relationship between patch size and plant reproduction using an experiment in a Chihuahuan Desert grassland. We tested the hypothesis that reproductive effort and success of a dominant grass (Bouteloua eriopoda) would vary predictably with patch size. We found that focal plants in medium-sized patches featured higher rates of grass reproductive success than when plants occupied either large patch interiors or small patches. These patterns support the existence of scale-dependent feedbacks in Chihuahuan Desert grasslands and indicate an optimal patch size for reproductive effort and success in B. eriopoda. We discuss the implications of these results for detecting ecological thresholds in desert grasslands.
The D-Region Ionospheric Response to the 2017 Solar Eclipse
NASA Astrophysics Data System (ADS)
Cohen, M.; McCormick, J.; Gross, N. C.; Higginson-Rollins, M. A.
2017-12-01
VLF/LF radio remote sensing (0.5-500 kHz) is an effective means for quantifying the D-region ionosphere (60-90 km altitude). Disturbances in the ionospheric electron density induce changes in the propagation of VLF/LF signals, so a network of transmitters and receivers can effectively "image" a disturbed region. VLF/LF signals can all be detected from 100s-1000s of km away. We utilize Georgia Tech's network of highly-sensitive VLF/LF receivers to quantify the lower ionospheric response to the "Great American Eclipse". Nine of these were deployed and operational across the Continental US, Alaska and Puerto Rico all operated successfully. Each receiver synchronously recorded the full radio spectrum between 0.5-470 kHz. The included figure shows the eclipse track at 80 km altitude with a green swath. The nine operational receivers are shown with blue stars, and operational VLF/LF transmitters in dark red. Gray lines are shown for each great-circle path linking a VLF/LF transmitter to a receiver. This constellation forms a dense spider's-web grid of radio links, with which we can effectively image the disturbed patch of the D-region ionosphere as it moves across the country. In addition, shown in yellow are NDGPS transmitters which lie between 285-325 kHz. The red dots are the 230,000 geolocated lightning strokes during the 90-mintue eclipse pass, each of which emitted an intense VLF/LF impulse. These are also detected by our receivers. We present our observations and comparison with a theoretical model, using a combination of three techniques established by a series of three 2017 journal papers: (1) Polarization measurements of VLF/LF transmitter signals, (2) Lightning-generated VLF sferics detected 1000s of km away, and (3) NDGPS beacons near 300 kHz for shorter-range sounding of a small patch of the ionosphere. We find evidence of large scale ionospheric changes which affect the D-region over the entire continental region with a slowly-varying signal perturbation. At some sites close to the totality zone, however, we have evidence of forward scattering from the shadow of the moon, which effectively is a patch of nighttime surrounded by daytime, that can only be observed in a narrower region around the totality zone. Implications of these results for D-region ionospheric dynamics are discussed.
Current usage and future directions for the bovine pericardial patch.
Li, Xin; Guo, Yuanyuan; Ziegler, Kenneth R; Model, Lynn S; Eghbalieh, Sammy D D; Brenes, Robert A; Kim, Susun T; Shu, Chang; Dardik, Alan
2011-05-01
Bovine pericardium (BP) is widely used in surgery and is commonly used as a patch after arteriotomy in cardiovascular surgery. BP patches have several advantages compared with prosthetic patches, including superior biocompatability, easy handling, less suture line bleeding, and possibly reduced rates of infection. These advantages of BP have led to its common use during carotid endarterectomy (CEA). However, long-term clinical results reported after CEA have suggested several issues that may be related to the patch, including restenosis, pseudoaneurysm formation, infection, fibrosis, calcification, and thrombosis. These complications may diminish the long-term efficacy of CEA and suggest potential areas for improvement of surgical patches. Understanding the mechanisms by which BP heals after patch angioplasty may lead to next generation tissue-engineered patches. Published by Elsevier Inc.
Current usage and future directions for the bovine pericardial patch
Li, Xin; Guo, Yuanyuan; Ziegler, Kenneth; Model, Lynn; Eghbalieh, Sammy D. D.; Brenes, Robert; Kim, Susun; Shu, Chang; Dardik, Alan
2010-01-01
Bovine pericardium is widely used in surgery and is commonly used for a patch after arteriotomy during cardiovascular surgery. Bovine pericardial patches have several advantages compared to prosthetic patches, including superior biocompatability, easy handling, less suture line bleeding and possibly reduced rates of infection. These advantages of bovine pericardium have led to its common use during carotid endarterectomy. However, long-term clinical results reported after carotid endarterectomy have suggested several issues that may be related to the patch including restenosis, pseudoaneurysm formation, infection, fibrosis, calcification and thrombosis. These complications may diminish the long-term efficacy of carotid endarterectomy and suggest potential areas for improvement of surgical patches. Understanding the mechanisms by which bovine pericardium heals after patch angioplasty may lead to next generation tissue engineered patches. PMID:21276709
Integrated multiple patch-clamp array chip via lateral cell trapping junctions
NASA Astrophysics Data System (ADS)
Seo, J.; Ionescu-Zanetti, C.; Diamond, J.; Lal, R.; Lee, L. P.
2004-03-01
We present an integrated multiple patch-clamp array chip by utilizing lateral cell trapping junctions. The intersectional design of a microfluidic network provides multiple cell addressing and manipulation sites for efficient electrophysiological measurements at a number of patch sites. The patch pores consist of openings in the sidewall of a main fluidic channel, and a membrane patch is drawn into a smaller horizontal channel. This device geometry not only minimizes capacitive coupling between the cell reservoir and the patch channel, but also allows simultaneous optical and electrical measurements of ion channel proteins. Evidence of the hydrodynamic placement of mammalian cells at the patch sites as well as measurements of patch sealing resistance is presented. Device fabrication is based on micromolding of polydimethylsiloxane, thus allowing inexpensive mass production of disposable high-throughput biochips.
Huang, Yi-Fei; Golding, G Brian
2015-02-15
A number of statistical phylogenetic methods have been developed to infer conserved functional sites or regions in proteins. Many methods, e.g. Rate4Site, apply the standard phylogenetic models to infer site-specific substitution rates and totally ignore the spatial correlation of substitution rates in protein tertiary structures, which may reduce their power to identify conserved functional patches in protein tertiary structures when the sequences used in the analysis are highly similar. The 3D sliding window method has been proposed to infer conserved functional patches in protein tertiary structures, but the window size, which reflects the strength of the spatial correlation, must be predefined and is not inferred from data. We recently developed GP4Rate to solve these problems under the Bayesian framework. Unfortunately, GP4Rate is computationally slow. Here, we present an intuitive web server, FuncPatch, to perform a fast approximate Bayesian inference of conserved functional patches in protein tertiary structures. Both simulations and four case studies based on empirical data suggest that FuncPatch is a good approximation to GP4Rate. However, FuncPatch is orders of magnitudes faster than GP4Rate. In addition, simulations suggest that FuncPatch is potentially a useful tool complementary to Rate4Site, but the 3D sliding window method is less powerful than FuncPatch and Rate4Site. The functional patches predicted by FuncPatch in the four case studies are supported by experimental evidence, which corroborates the usefulness of FuncPatch. The software FuncPatch is freely available at the web site, http://info.mcmaster.ca/yifei/FuncPatch golding@mcmaster.ca Supplementary data are available at Bioinformatics online. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Arbitrarily shaped dual-stacked patch antennas: A hybrid FEM simulation
NASA Technical Reports Server (NTRS)
Gong, Jian; Volakis, John L.
1995-01-01
A dual-stacked patch antenna is analyzed using a hybrid finite element - boundary integral (FE-BI) method. The metallic patches of the antenna are modeled as perfectly electric conducting (PEC) plates stacked on top of two different dielectric layers. The antenna patches may be of any shape and the lower patch is fed by a coaxial cable from underneath the ground plane or by an aperture coupled microstrip line. The ability of the hybrid FEM technique for the stacked patch antenna characterization will be stressed, and the EM coupling mechanism is also discussed with the aid of the computed near field patterns around the patches.
... the adhesive surface of the patch, the clear plastic protective strip should be peeled off and discarded. ... needed, remove the patch and dispose of it. Wrap the patch in tissue or paper to avoid ...
... will be applying the patch. Cut open the envelope containing the patches, cutting on the dotted line ... it. Pull apart the zipper seal on the envelope and remove one patch. Reseal the envelope by ...
Monitoring Pregnant Women’s Illicit Opiate and Cocaine Use With Sweat Testing
Brunet, Bertrand R.; Barnes, Allan J.; Choo, Robin E.; Mura, Patrick; Jones, Hendrée E.; Huestis, Marilyn A.
2011-01-01
Dependence on illicit drugs during pregnancy is a major public health concern as there may be associated adverse maternal, fetal, and neonatal consequences. Sweat patches (n = 389) were collected from 39 pregnant volunteers who provided written informed consent for this Institutional Review Board-approved protocol and wore patches, replaced approximately weekly, from study entry until delivery. Patches were analyzed for opiates (heroin, 6-acetylmor-phine, 6-acetylcodeine, morphine and codeine) and cocaine (cocaine, benzoylecgonine, ecgonine methyl ester, anhydroecgonine methyl ester) by solid phase extraction and gas chromatography mass spectrometry. Seventy-one percent (276) of collected sweat patches were ≥5 ng per patch (limit of quantification) for one or more analytes. Cocaine was present in 254 (65.3%) patches in concentrations ranging from 5.2 to 11,835 ng per patch with 154 of these high enough to satisfy the proposed Substance Abuse and Mental Health Services Administration guidelines for a confirmatory drug test (25 ng per patch). Interestingly, 6-acetylmorphine was the most prominent opiate analyte documented in 134 patches (34.4%) with 11.3% exceeding the proposed opiate Substance Abuse and Mental Health Services Administration cut-off (25 ng per patch). Heroin was identified in fewer patches (77), but in a similar concentration range (5.3–345.4 ng per patch). Polydrug use was evident by the presence of both cocaine and opiate metabolites in 136 (35.0%) patches. Sweat testing is an effective method for monitoring abstinence or illicit drug use relapse in this high-risk population of pregnant opiate- and/or cocaine-dependent women. PMID:19927046
Gür, Özer Erdem; Ensari, Nuray; Öztürk, Mehmet Türker; Boztepe, Osman Fatih; Gün, Taylan; Selçuk, Ömer Tarık; Renda, Levent
2016-10-01
(1) To evaluate the effects of a platelet-rich fibrin (PRF) membrane in the repair of traumatic tympanic membrane (TM) perforations; and (2) to compare the use of a PRF membrane with the paper patch technique with regard to recovery rates, healing time, and correction of the mean air-bone gap. A randomized, prospective analysis was performed for 60 patients who were treated for traumatic TM perforations using one of the two methods. Closure rate, speed of healing, and hearing gain were compared between the PRF (Group 1) and paper patch (Group 2) groups. Closure was obtained in 28 (93%) perforations in Group 1 and 25 (83%) perforations in Group 2 (p > 0.05). On day 10, full closure of the TM was observed in 24 (80%) patients in Group 1 and 16 (53%) patients in Group 2 (p < 0.05). The improvement in the mean air-bone gap was 14.1 dB in Group 1 and 12.4 dB in Group 2 on post-operative day 45 (p < 0.05). In comparison with the paper patch method, PRF, a new method, provided more rapid healing with more successful audiological results, and with no requirement for a second procedure.
A Ka-Band (26 GHz) Circularly Polarized 2x2 Microstrip Patch Sub-Array with Compact Feed
NASA Technical Reports Server (NTRS)
Chrysler, Andrew; Furse, Cynthia; Simons, Rainee N.; Miranda, Felix A.
2017-01-01
A Ka-Band (26 gigahertz) 2 by 2 sub-array with square-shaped microstrip patch antenna elements having two truncated corners for circular polarization (CP) is presented. In addition, the layout for a new compact microstrip feed network for the sub-array is also presented. The compact feed network offers a footprint size reduction of near 60 percent over traditional sub-array at 26 gigahertz. Experimental data indicates that a truncation amount a equals 0.741 millimeters for an isolated patch element results in a return loss (S (sub II)) of minus 35 decibels at 26.3 gigahertz. Furthermore, the measured S (sub II) for the proof-of-concept sub-array with the above elements is better than minus 10.0 decibels at 27.7 gigahertz. However, the impedance match and the operating frequency can be fine-tuned to 26 gigahertz by adjusting the feed network dimensions. Lastly, good agreement is observed between the measured and simulated S (sub II) for the subarray for both right hand and left hand CP. The goal of this effort is utilize the above sub-array as a building block for a larger N by N element array, which would serve as a feed for a reflector antenna for satellite communications.
A conducting polymer with enhanced electronic stability applied in cardiac models
Mawad, Damia; Mansfield, Catherine; Lauto, Antonio; Perbellini, Filippo; Nelson, Geoffrey W.; Tonkin, Joanne; Bello, Sean O.; Carrad, Damon J.; Micolich, Adam P.; Mahat, Mohd M.; Furman, Jennifer; Payne, David; Lyon, Alexander R.; Gooding, J. Justin; Harding, Sian E.; Terracciano, Cesare M.; Stevens, Molly M.
2016-01-01
Electrically active constructs can have a beneficial effect on electroresponsive tissues, such as the brain, heart, and nervous system. Conducting polymers (CPs) are being considered as components of these constructs because of their intrinsic electroactive and flexible nature. However, their clinical application has been largely hampered by their short operational time due to a decrease in their electronic properties. We show that, by immobilizing the dopant in the conductive scaffold, we can prevent its electric deterioration. We grew polyaniline (PANI) doped with phytic acid on the surface of a chitosan film. The strong chelation between phytic acid and chitosan led to a conductive patch with retained electroactivity, low surface resistivity (35.85 ± 9.40 kilohms per square), and oxidized form after 2 weeks of incubation in physiological medium. Ex vivo experiments revealed that the conductive nature of the patch has an immediate effect on the electrophysiology of the heart. Preliminary in vivo experiments showed that the conductive patch does not induce proarrhythmogenic activities in the heart. Our findings set the foundation for the design of electronically stable CP-based scaffolds. This provides a robust conductive system that could be used at the interface with electroresponsive tissue to better understand the interaction and effect of these materials on the electrophysiology of these tissues. PMID:28138526
In vivo results of hydrogel composite pericardial substitutes.
Blue, M A; Guilbeau, E J; Brandon, T A; Walker, A S; Bjotvedt, G; Fisk, R L
1991-01-01
In this study, two improved pericardial patches were developed and evaluated for their efficacy as pericardial substitutes. The patches are composites consisting of a hydrogel (PHEMA) that coats an underlying mesh (either ETFE or PET). Studies were conducted using subcutaneous implants in rats and pericardial patch implants in greyhound dogs. Adhesions between the substitute and pericardium and the epicardium were minimal. The ETFE composite patch caused an unacceptable epicardial reaction. The PET patch results were encouraging; the epicardium was largely unaffected by the patch.
Apparatus and Method for Improving the Gain and Bandwidth of a Microstrip Patch Antenna
2013-09-30
improving both the gain and the bandwidth of a microstrip patch antenna . (2) Description of the Prior Art [0004] A patch antenna , also referred to as a...rectangular microstrip antenna , is a type of radio antenna with a low profile that can be mounted on a flat surface. The patch antenna includes a...patch antenna form a Attorney Docket No. 101925 2 of 11 resonant piece of microstrip transmission line. The patch is designed to have a length of
Nanopore Logic Operation with DNA to RNA Transcription in a Droplet System.
Ohara, Masayuki; Takinoue, Masahiro; Kawano, Ryuji
2017-07-21
This paper describes an AND logic operation with amplification and transcription from DNA to RNA, using T7 RNA polymerase. All four operations, (0 0) to (1 1), with an enzyme reaction can be performed simultaneously, using four-droplet devices that are directly connected to a patch-clamp amplifier. The output RNA molecule is detected using a biological nanopore with single-molecule translocation. Channel current recordings can be obtained using the enzyme solution. The integration of DNA logic gates into electrochemical devices is necessary to obtain output information in a human-recognizable form. Our method will be useful for rapid and confined DNA computing applications, including the development of programmable diagnostic devices.
The effect of travel loss on evolutionarily stable distributions of populations in space
DeAngelis, D.L.; Wolkowicz, G.S.K.; Lou, Y.; Jiang, Y.; Novak, M.; Svanback, R.; Araujo, M.S.; Jo, Y.S.; Cleary, E.A.
2011-01-01
A key assumption of the ideal free distribution (IFD) is that there are no costs in moving between habitat patches. However, because many populations exhibit more or less continuous population movement between patches and traveling cost is a frequent factor, it is important to determine the effects of costs on expected population movement patterns and spatial distributions. We consider a food chain (tritrophic or bitrophic) in which one species moves between patches, with energy cost or mortality risk in movement. In the two-patch case, assuming forced movement in one direction, an evolutionarily stable strategy requires bidirectional movement, even if costs during movement are high. In the N-patch case, assuming that at least one patch is linked bidirectionally to all other patches, optimal movement rates can lead to source-sink dynamics where patches with negative growth rates are maintained by other patches with positive growth rates. As well, dispersal between patches is not balanced (even in the two-patch case), leading to a deviation from the IFD. Our results indicate that cost-associated forced movement can have important consequences for spatial metapopulation dynamics. Relevance to marine reserve design and the study of stream communities subject to drift is discussed. ?? 2011 by The University of Chicago.
Han, Hyun Jeong; Kim, Byeong C; Lee, Jun-Young; Ryu, Seung-Ho; Na, Hae Ri; Yoon, Soo Jin; Park, Hyun Young; Shin, Joon Hyun; Cho, Soo-Jin; Yi, Hyon-Ah; Choi, Mun Seong; Heo, Jae-Hyeok; Park, Kyung Won; Kim, Kwang K; Choi, Seong Hye
2012-01-01
The apolipoprotein E (APOE) genotype in response to pharmacological treatments in patients with Alzheimer's disease (AD) remains a matter of controversy. This analysis investigated the effect of the APOE genotype on the clinical response to rivastigmine transdermal patch monotherapy or memantine plus rivastigmine patch in patients with mild to moderate AD. Two hundred and six (n = 206) patients with probable AD and Mini-Mental State Examination (MMSE) scores of 10-20 were randomized to rivastigmine patch monotherapy or memantine plus rivastigmine patch for 24 weeks. Of the 206 patients with probable AD, 146 patients who consented to genetic testing for APOE were included and assessed for this subgroup study. There were no significant differences on MMSE, NPI, ADAS-cog, ADCS-ADL, CDR-SB, NPI and FAB between rivastigmine patch monotherapy and memantine plus rivastigmine patch according to the APOE genotype. However, patients with moderately severe AD (MMSE ≤15) who were APOE ε4 carriers showed higher responder rates on ADCS-ADL with memantine plus rivastigmine patch compared to rivastigmine patch monotherapy. Moderately severe AD patients with the APOE ε4 allele may respond more favorably to memantine plus rivastigmine patch than ε4 noncarriers. Copyright © 2012 S. Karger AG, Basel.
On the Persistent Shape and Coherence of Pulsating Auroral Patches
NASA Astrophysics Data System (ADS)
Humberset, B. K.; Gjerloev, J. W.; Mann, I. R.; Michell, R. G.; Samara, M.
2018-05-01
The pulsating aurora covers a broad range of fluctuating shapes that are poorly characterized. The purpose of this paper is therefore to provide objective and quantitative measures of the extent to which pulsating auroral patches maintain their shape, drift and fluctuate in a coherent fashion. We present results from a careful analysis of pulsating auroral patches using all-sky cameras. We have identified four well-defined individual patches that we follow in the patch frame of reference. In this way we avoid the space-time ambiguity which complicates rocket and satellite measurements. We find that the shape of the patches is remarkably persistent with 85-100% of the patch being repeated for 4.5-8.5 min. Each of the three largest patches has a temporal correlation with a negative dependence on distance, and thus does not fluctuate in a coherent fashion. A time-delayed response within the patches indicates that the so-called streaming mode might explain the incoherency. The patches appear to drift differently from the SuperDARN-determined E→×B→ convection velocity. However, in a nonrotating reference frame the patches drift with 230-287 m/s in a north eastward direction, which is what typically could be expected for the convection return flow.
Landscape matrix mediates occupancy dynamics of Neotropical avian insectivores
Kennedy, Christina M.; Campbell Grant, Evan H.; Neel, Maile C.; Fagan, William F.; Marpa, Peter P.
2011-01-01
In addition to patch-level attributes (i.e., area and isolation), the nature of land cover between habitat patches (the matrix) may drive colonization and extinction dynamics in fragmented landscapes. Despite a long-standing recognition of matrix effects in fragmented systems, an understanding of the relative impacts of different types of land cover on patterns and dynamics of species occurrence remains limited. We employed multi-season occupancy models to determine the relative influence of patch area, patch isolation, within-patch vegetation structure, and landscape matrix on occupancy dynamics of nine Neotropical nsectivorous birds in 99 forest patches embedded in four matrix types (agriculture, suburban evelopment, bauxite mining, and forest) in central Jamaica. We found that within-patch vegetation structure and the matrix type between patches were more important than patch area and patch isolation in determining local colonization and local extinction probabilities, and that the effects of patch area, isolation, and vegetation structure on occupancy dynamics tended to be matrix and species dependent. Across the avian community, the landscape matrix influenced local extinction more than local colonization, indicating that extinction processes, rather than movement, likely drive interspecific differences in occupancy dynamics. These findings lend crucial empirical support to the hypothesis that species occupancy dynamics in fragmented systems may depend greatly upon the landscape context.
Comparing reliabilities of strip and conventional patch testing.
Dickel, Heinrich; Geier, Johannes; Kreft, Burkhard; Pfützner, Wolfgang; Kuss, Oliver
2017-06-01
The standardized protocol for performing the strip patch test has proven to be valid, but evidence on its reliability is still missing. To estimate the parallel-test reliability of the strip patch test as compared with the conventional patch test. In this multicentre, prospective, randomized, investigator-blinded reliability study, 132 subjects were enrolled. Simultaneous duplicate strip and conventional patch tests were performed with the Finn Chambers ® on Scanpor ® tape test system and the patch test preparations nickel sulfate 5% pet., potassium dichromate 0.5% pet., and lanolin alcohol 30% pet. Reliability was estimated by the use of Cohen's kappa coefficient. Parallel-test reliability values of the three standard patch test preparations turned out to be acceptable, with slight advantages for the strip patch test. The differences in reliability were 9% (95%CI: -8% to 26%) for nickel sulfate and 23% (95%CI: -16% to 63%) for potassium dichromate, both favouring the strip patch test. The standardized strip patch test method for the detection of allergic contact sensitization in patients with suspected allergic contact dermatitis is reliable. Its application in routine clinical practice can be recommended, especially if the conventional patch test result is presumably false negative. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Gruber, D; Skřivánek, A; Serrani, M; Lanius, V; Merz, M
2015-02-01
To investigate the bleeding pattern and cycle control parameters of a contraceptive patch containing 0.55 mg ethinyl estradiol (EE) and 2.1 mg gestodene (GSD) compared with a patch containing 0.6 mg EE and 6 mg norelgestromin (NGMN). In this phase III, open-label, randomized, parallel-group trial, healthy women aged 18-35 years (smokers aged 18-30 years) received either the EE/GSD patch (n=200) or the EE/NGMN patch (n=198). Treatment consisted of one patch per week for 3 weeks followed by a 7-day, patch-free interval for seven cycles. Bleeding control was assessed in two 90-day reference periods. In reference period 1, mean number of bleeding/spotting days was comparable across treatment groups (p>0.05). However, in reference period 2, there were fewer bleeding/spotting days in the EE/GSD patch group (15.7 versus 18.4; p<0.0001). Mean number of bleeding/spotting episodes was comparable across groups for both reference periods, but bleeding/spotting episodes were shorter for the EE/GSD patch than the EE/NGMN patch during reference period 1 (5.13 days versus 5.53 days, respectively; p<0.05) and reference period 2 (5.07 versus 5.66; p=0.0001). Both treatment groups showed a similar frequency of withdrawal bleeding episodes; however, across all seven cycles, the length of these episodes was consistently shorter with the EE/GSD patch (p<0.01). There were no notable treatment differences in intracyclic bleeding. Bleeding pattern and cycle control achieved with the EE/GSD patch was similar to that of the EE/NGMN patch. The paper presents data on the bleeding pattern and cycle control parameters of an investigational transdermal contraceptive patch containing EE and GSD compared with an approved contraceptive patch containing EE and NGMN. This descriptive study found that bleeding patterns associated with the EE/GSD patch were similar to those of an EE/NGMN patch providing higher EE exposure. Copyright © 2015 Elsevier Inc. All rights reserved.
Transdermal patches: history, development and pharmacology
Pastore, Michael N; Kalia, Yogeshvar N; Horstmann, Michael; Roberts, Michael S
2015-01-01
Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. This review begins with the earliest topical therapies and traces topical delivery to the present-day transdermal patches, describing along the way the initial trials, devices and drug delivery systems that underpin current transdermal patches and their actives. This is followed by consideration of the evolution in the various patch designs and their limitations as well as requirements for actives to be used for transdermal delivery. The properties of and issues associated with the use of currently marketed products, such as variability, safety and regulatory aspects, are then described. The review concludes by examining future prospects for transdermal patches and drug delivery systems, such as the combination of active delivery systems with patches, minimally invasive microneedle patches and cutaneous solutions, including metered-dose systems. PMID:25560046
A sparse representation-based approach for copy-move image forgery detection in smooth regions
NASA Astrophysics Data System (ADS)
Abdessamad, Jalila; ElAdel, Asma; Zaied, Mourad
2017-03-01
Copy-move image forgery is the act of cloning a restricted region in the image and pasting it once or multiple times within that same image. This procedure intends to cover a certain feature, probably a person or an object, in the processed image or emphasize it through duplication. Consequences of this malicious operation can be unexpectedly harmful. Hence, the present paper proposes a new approach that automatically detects Copy-move Forgery (CMF). In particular, this work broaches a widely common open issue in CMF research literature that is detecting CMF within smooth areas. Indeed, the proposed approach represents the image blocks as a sparse linear combination of pre-learned bases (a mixture of texture and color-wise small patches) which allows a robust description of smooth patches. The reported experimental results demonstrate the effectiveness of the proposed approach in identifying the forged regions in CM attacks.
A causal relationship between face-patch activity and face-detection behavior.
Sadagopan, Srivatsun; Zarco, Wilbert; Freiwald, Winrich A
2017-04-04
The primate brain contains distinct areas densely populated by face-selective neurons. One of these, face-patch ML, contains neurons selective for contrast relationships between face parts. Such contrast-relationships can serve as powerful heuristics for face detection. However, it is unknown whether neurons with such selectivity actually support face-detection behavior. Here, we devised a naturalistic face-detection task and combined it with fMRI-guided pharmacological inactivation of ML to test whether ML is of critical importance for real-world face detection. We found that inactivation of ML impairs face detection. The effect was anatomically specific, as inactivation of areas outside ML did not affect face detection, and it was categorically specific, as inactivation of ML impaired face detection while sparing body and object detection. These results establish that ML function is crucial for detection of faces in natural scenes, performing a critical first step on which other face processing operations can build.
CARA Status and Upcoming Enhancements
NASA Technical Reports Server (NTRS)
Johnson, Megan
2017-01-01
CAS 8.4.3 was deployed to operations on 13 June 2017. Discrepancies Between 3D Pc Estimates and advanced Monte Carlo Equinoctial-Sampling Pc Estimates discovered and discussed at 23 May 2017 Useras (Registered Trademark) Forum. The patch created the Reporting Pc, which is the greater value between the calculated 2D and 3D Pc values This changed the Pc reported in the CDMs to the Reporting Pc This changed the Pc reported on the Summary Report to the Reporting Pc This changed the Pc reported on Maneuver Screening Analysis (MSA) Report to the Reporting Pc. Both the 2D and 3D Pc added to the Summary Report details section The patch also updated the 3D Pc algorithm to eliminate velocity covariance from the Pc calculation This will bring 2D and 3D Pc into close alignment for vast majority of events, particularly for the events in which the 2D/3D discrepancy was found.
Polonchuk, Liudmila
2012-01-01
The Patchliner® temperature-controlled automated patch clamp system was evaluated for testing drug effects on potassium currents through human ether-à-go-go related gene (hERG) channels expressed in Chinese hamster ovary cells at 35–37°C. IC50 values for a set of reference drugs were compared with those obtained using the conventional voltage clamp technique. The results showed good correlation between the data obtained using automated and conventional electrophysiology. Based on these results, the Patchliner® represents an innovative automated electrophysiology platform for conducting the hERG assay that substantially increases throughput and has the advantage of operating at physiological temperature. It allows fast, accurate, and direct assessment of channel function to identify potential proarrhythmic side effects and sets a new standard in ion channel research for drug safety testing. PMID:22303293
NASA Technical Reports Server (NTRS)
Cure, David; Weller, Thomas; Miranda, Felix A.
2011-01-01
In this paper, a comparison between Jerusalem Cross (JC) and Square Patch (SP) based Frequency Selected Surfaces (FSS) for low profile antenna applications is presented. The comparison is aimed at understanding the performance of low profile antennas backed by high impedance surfaces. In particular, an end loaded planar open sleeve dipole (ELPOSD) antenna is examined due to the various parameters within its configuration, offering significant design flexibility and a wide operating bandwidth. Measured data of the antennas demonstrate that increasing the number of unit cells improves the fractional bandwidth. The antenna bandwidth increased from 0.8% to 1.8% and from 0.8% to 2.7% for the JC and SP structures, respectively. The number of unit cells was increased from 48 to 80 for the JC-FSS and from 24 to 48 for the SP-FSS.
Foraging for brain stimulation: toward a neurobiology of computation.
Gallistel, C R
1994-01-01
The self-stimulating rat performs foraging tasks mediated by simple computations that use interreward intervals and subjective reward magnitudes to determine stay durations. This is a simplified preparation in which to study the neurobiology of the elementary computational operations that make cognition possible, because the neural signal specifying the value of a computationally relevant variable is produced by direct electrical stimulation of a neural pathway. Newly developed measurement methods yield functions relating the subjective reward magnitude to the parameters of the neural signal. These measurements also show that the decision process that governs foraging behavior divides the subjective reward magnitude by the most recent interreward interval to determine the preferability of an option (a foraging patch). The decision process sets the parameters that determine stay durations (durations of visits to foraging patches) so that the ratios of the stay durations match the ratios of the preferabilities.
Perforated peptic ulcer (PPU) in pregnancy during Ramadan fasting.
Gali, B M; Ibrahim, A G; Chama, C M; Mshelia, H B; Abubakar, A; Takai, I U; Takie, U; Bwala, S
2011-01-01
Perforated Peptic Ulcer (PPU) is extremely rare in pregnancy. We report a case of perforated peptic ulcer in pregnancy during Ramadan fasting. The patient is a 16 years old primigravida who presented with features of peritonitis at 28weeks of gestation while fasting during Ramadan. Ultrasound scan reported a singleton live fetus at 28 weeks gestation. At laparotomy via upper midline incision; a 1 cm roundish perforation located on the duodenum anteriorly was found with about a litre of gastric juice mixed with blood and food particles in the peritoneal cavity. The perforation was close transversely with omental patch (Modified Graham's patch) and peritoneal lavage done with warm saline. She had a preterm delivery of a 1 kg baby 3 days post-operatively by a spontaneous vaginal delivery, but the baby died 3 days later. Perforated Peptic Ulcer(PPU) though rare in pregnancy can occur and fasting can be a risk factor.
Effects of Sediment Patches on Sediment Transport Predictions in Steep Mountain Channels
NASA Astrophysics Data System (ADS)
Monsalve Sepulveda, A.; Yager, E.
2013-12-01
Bed surface patches occur in most gravel-bedded rivers and in steep streams can be divided between relatively immobile boulders and more mobile patches of cobbles and gravel. This spatial variability in grain size, roughness and sorting impact bed load transport by altering the relative local mobility of different grain sizes and creating complex local flow fields. Large boulders also bear a significant part of the total shear stress and we hypothesize that the remaining shear stress on a given mobile patch is a distribution of values that depend on the local topography, patch type and location relative to the large roughness elements and thalweg. Current sediment transport equations do not account for the variation in roughness, local flow and grain size distributions on and between patches and often use an area-weighted approach to obtain a representative grain size distribution and reach-averaged shear stress. Such equations also do not distinguish between active (patches where at least one grain size is in motion) and inactive patches or include the difference in mobility between patch classes as result of spatial shear stress distributions. To understand the effects of sediment patches on sediment transport in steep channels, we calculated the shear stress distributions over a range of patch classes in a 10% gradient step-pool stream. We surveyed the bed with a high density resolution (every 5 cm in horizontal and vertical directions over a 40 m long reach) using a total station and terrestrial LiDAR, mapped and classified patches by their grain size distributions, and measured water surface elevations and mean velocities for low to moderate flow events. Using these data we calibrated a quasi-three dimensional model (FaSTMECH) to obtain shear stress distributions over each patch for a range of flow discharges. We modified Parker's (1990) equations to use the calculated shear stress distribution, measured grain sizes, and a specific hiding function for each patch class, and then added the bedload fluxes for each patch to calculate the reach-averaged sediment transport rate. Sediment mobility in patches was highly dependent on the patch's class and location relative to the thalweg and large roughness elements. Compared to deterministic formulations, the use of distributions of shear stress improved predictions of bedload transport in steep mountain channels.
Patch size has no effect on insect visitation rate per unit area in garden-scale flower patches
NASA Astrophysics Data System (ADS)
Garbuzov, Mihail; Madsen, Andy; Ratnieks, Francis L. W.
2015-01-01
Previous studies investigating the effect of flower patch size on insect flower visitation rate have compared relatively large patches (10-1000s m2) and have generally found a negative relationship per unit area or per flower. Here, we investigate the effects of patch size on insect visitation in patches of smaller area (range c. 0.1-3.1 m2), which are of particular relevance to ornamental flower beds in parks and gardens. We studied two common garden plant species in full bloom with 6 patch sizes each: borage (Borago officinalis) and lavender (Lavandula × intermedia 'Grosso'). We quantified flower visitation by insects by making repeated counts of the insects foraging at each patch. On borage, all insects were honey bees (Apis mellifera, n = 5506 counts). On lavender, insects (n = 737 counts) were bumble bees (Bombus spp., 76.9%), flies (Diptera, 22.4%), and butterflies (Lepidoptera, 0.7%). On both plant species we found positive linear effects of patch size on insect numbers. However, there was no effect of patch size on the number of insects per unit area or per flower and, on lavender, for all insects combined or only bumble bees. The results show that it is possible to make unbiased comparisons of the attractiveness of plant species or varieties to flower-visiting insects using patches of different size within the small scale range studied and make possible projects aimed at comparing ornamental plant varieties using existing garden flower patches of variable area.
Patching. Restitching business portfolios in dynamic markets.
Eisenhardt, K M; Brown, S L
1999-01-01
In turbulent markets, businesses and opportunities are constantly falling out of alignment. New technologies and emerging markets create fresh opportunities. Converging markets produce more. And of course, some markets fade. In this landscape of continuous flux, it's more important to build corporate-level strategic processes that enable dynamic repositioning than it is to build any particular defensible position. That's why smart corporate strategists use patching, a process of mapping and remapping business units to create a shifting mix of highly focused, tightly aligned businesses that can respond to changing market opportunities. Patching is not just another name for reorganizing; patchers have a distinctive mindset. Traditional managers see structure as stable; patching managers believe structure is inherently temporary. Traditional managers set corporate strategy first, but patching managers keep the organization focused on the right set of business opportunities and let strategy emerge from individual businesses. Although the focus of patching is flexibility, the process itself follows a pattern. Patching changes are usually small in scale and made frequently. Patching should be done quickly; the emphasis is on getting the patch about right and fixing problems later. Patches should have a test drive before they're formalized but then be tightly scripted after they've been announced. And patching won't work without the right infrastructure: modular business units, fine-grained and complete unit-level metrics, and companywide compensation parity. The authors illustrate how patching works and point out some common stumbling blocks.
NASA Astrophysics Data System (ADS)
Lapusta, N.; Liu, Y.
2007-12-01
Heterogeneity in fault properties can have significant effect on dynamic rupture propagation and aseismic slip. It is often assumed that a fixed heterogeneity would have similar effect on fault slip throughout the slip history. We investigate dynamic rupture interaction with a fault patch of higher normal stress over several earthquake cycles in a three-dimensional model. We find that the influence of the heterogeneity on dynamic events has significant variation and depends on prior slip history. We consider a planar strike-slip fault governed by rate and state friction and driven by slow tectonic loading on deeper extension of the fault. The 30 km by 12 km velocity-weakening region, which is potentially seismogenic, is surrounded by steady-state velocity-strengthening region. The normal stress is constant over the fault, except in a circular patch of 2 km in diameter located in the seismogenic region, where normal stress is higher than on the rest of the fault. Our simulations employ the methodology developed by Lapusta and Liu (AGU, 2006), which is able to resolve both dynamic and quasi-static stages of spontaneous slip accumulation in a single computational procedure. The initial shear stress is constant on the fault, except in a small area where it is higher and where the first large dynamic event initiates. For patches with 20%, 40%, 60% higher normal stress, the first event has significant dynamic interaction with the patch, creating a rupture speed decrease followed by a supershear burst and larger slip around the patch. Hence, in the first event, the patch acts as a seismic asperity. For the case of 100% higher stress, the rupture is not able to break the patch in the first event. In subsequent dynamic events, the behavior depends on the strength of heterogeneity. For the patch with 20% higher normal stress, dynamic rupture in subsequent events propagates through the patch without any noticeable perturbation in rupture speed or slip. In particular, supershear propagation and additional slip accumulation around the patch are never repeated in the simulated history of the fault, and the patch stops manifesting itself as a seismic asperity. This is due to higher shear stress that is established at the patch after the first earthquake cycle. For patches with higher normal stress, shear stress redistribution also occurs, but it is less effective. The patches with 40% and 60% higher normal stress continue to affect rupture speed and fault slip in some of subsequent events, although the effect is much diminished with respect to the first event. For example, there are no supershear bursts. The patch with 100% higher normal stress is first broken in the second large event, and it retains significant influence on rupture speed and slip throughout the fault history, occasionally resulting in supershear bursts. Additional slip complexity emerges for patches with 40% and higher normal stress contrast. Since higher normal stress corresponds to a smaller nucleation size, nucleation of some events moves from the rheological transitions (where nucleation occurs in the cases with no stronger patch and with the patch of 20% higher normal stress) to the patches of higher normal stress. The patches nucleate both large, model-spanning, events, and small events that arrest soon after exiting the patch. Hence not every event that originates at the location of a potential seismic asperity is destined to be large, as its subsequent propagation is significantly influenced by the state of stress outside the patch.
Hofmann, Birte; Reinecke, Isabel; Schuett, Barbara; Merz, Martin; Zurth, Christian
2014-01-01
Objective: To determine the relative bioavailability of ethinyl estradiol (EE) and gestodene (GSD) after application of a novel transdermal contraceptive patch vs. a standard combined oral contraceptive (COC) pill (study 1), and to evaluate the pharmacokinetics (PK) of EE after application of the EE/GSD patch compared with an EE/norelgestromin (NGMN) patch (study 2). Materials: Participants were healthy, non-obese women aged 18 – 45 years (study 1) or 18 – 35 years (study 2). Compositions of study treatments were as follows: 0.55 mg EE/2.1 mg GSD (EE/GSD patch); 0.02 mg EE/0.075 mg GSD (standard COC); 0.6 mg EE/6 mg NGMN (EE/NGMN patch). Methods: In study 1, which consisted of 3 treatment periods (each followed by 7 patch- or pill-free days), treatments were administered in one of two randomized orders: either P–M–E (EE/GSD patch (P) every 7 days for 28 days → COC (M) once-daily for 21 days → two 7-day patch-wearing periods followed by one 10-day patch-wearing phase (E)), or the same treatments administered in sequence M–P–E. For study 2, participants received either the EE/GSD patch or EE/NGMN patch for seven treatment cycles (one patch per week for 3 weeks followed by a 7-day patch-free interval). Results: In study 1, average daily exposure to EE was similar for treatments P and M; the mean daily area under the concentration-time curve (AUC) ratio of treatment P vs. treatment M for EE was 1.06 (90% confidence interval (CI): 0.964 – 1.16), indicating average daily delivery similar to oral administration of 0.019 – 0.023 mg EE. For unbound GSD, average daily exposure was lower for treatment P vs. treatment M. The mean AUC ratio of treatment P vs. treatment M for unbound GSD was 0.820 (90% CI: 0.760 – 0.885), indicating average daily delivery from the patch of 0.057 – 0.066 mg GSD. Prolonged patch wearing did not result in a distinct decline in GSD and EE serum concentrations. In study 2, AUC at steady state (AUC0–168,ss), average steady-state serum concentration, and maximum steady-state serum concentration for EE was 2.0 – 2.7-fold higher for the EE/NGMN patch vs. the EE/GSD patch. The EE/GSD patch was well tolerated in both studies. Conclusions: Based on the 90% CI of the AUC ratio of oral treatment vs. patch application for unbound GSD and EE, the daily doses of GSD and EE released from the EE/GSD patch over the 7-day application period provided the same systemic exposure as those recorded after daily oral administration of a COC containing 0.02 mg EE and 0.06 mg GSD. The EE/GSD patch showed reduced EE exposure compared with the EE/NGMN patch. Together with its good tolerability, these properties support the EE/GSD patch as an effective and well-tolerated alternative to available transdermal and oral contraceptives. PMID:25295716
Reproducible, high performance patch antenna array apparatus and method of fabrication
Strassner, II, Bernd H.
2007-01-23
A reproducible, high-performance patch antenna array apparatus includes a patch antenna array provided on a unitary dielectric substrate, and a feed network provided on the same unitary substrate and proximity coupled to the patch antenna array. The reproducibility is enhanced by using photolithographic patterning and etching to produce both the patch antenna array and the feed network.
Methods of Making and Using Shape Memory Polymer Composite Patches
NASA Technical Reports Server (NTRS)
Hood, Patrick J.
2011-01-01
A method of repairing a composite component having a damaged area including: laying a composite patch over the damaged area: activating the shape memory polymer resin to easily and quickly mold said patch to said damaged area; deactivating said shape memory polymer so that said composite patch retains the molded shape; and bonding said composite patch to said damaged part.
Hernández-Ruedas, Manuel A.; Arroyo-Rodríguez, Víctor; Meave, Jorge A.; Martínez-Ramos, Miguel; Ibarra-Manríquez, Guillermo; Martínez, Esteban; Jamangapé, Gilberto; Melo, Felipe P. L.; Santos, Bráulio A.
2014-01-01
Rainforests are undergoing severe deforestation and fragmentation worldwide. A huge amount of small forest patches are being created, but their value in conserving biodiversity and forest structure is still controversial. Here, we demonstrate that in a species-rich and moderately-managed Mexican tropical landscape small rainforest patches (<100 ha) can be highly valuable for the conservation of tree diversity and forest structure. These patches showed diverse communities of native plants, including endangered species, and a new record for the country. Although the number of logged trees increased in smaller patches, patch size was a poor indicator of basal area, stem density, number of species, genera and families, and community evenness. Cumulative species-area curves indicated that all patches had a similar contribution to the regional species diversity. This idea also was supported by the fact that patches strongly differed in floristic composition (high β-diversity), independently of patch size. Thus, in agreement with the land-sharing approach, our findings support that small forest patches in moderately-managed landscapes should be included in conservation initiatives to maintain landscape heterogeneity, species diversity, and ecosystem services. PMID:24901954
Slime moulds use heuristics based on within-patch experience to decide when to leave.
Latty, Tanya; Beekman, Madeleine
2015-04-15
Animals foraging in patchy, non-renewing or slowly renewing environments must make decisions about how long to remain within a patch. Organisms can use heuristics ('rules of thumb') based on available information to decide when to leave the patch. Here, we investigated proximate patch-departure heuristics in two species of giant, brainless amoeba: the slime moulds Didymium bahiense and Physarum polycephalum. We explicitly tested the importance of information obtained through experience by eliminating chemosensory cues of patch quality. In P. polycephalum, patch departure was influenced by the consumption of high, and to a much lesser extent low, quality food items such that engulfing a food item increased patch-residency time. Physarum polycephalum also tended to forage for longer in darkened, 'safe' patches. In D. bahiense, engulfment of any food item increased patch residency irrespective of that food item's quality. Exposure to light had no effect on the patch-residency time of D. bahiense. Given that these organisms lack a brain, our results illustrate how the use of simple heuristics can give the impression that individuals make sophisticated foraging decisions. © 2015. Published by The Company of Biologists Ltd.
Isolation and functional characteristics of adherent phagocytic cells from mouse Peyer's patches.
MacDonald, T T; Carter, P B
1982-01-01
Attempts were made to isolate adherent phagocytic cells (macrophages) from mouse Peyer's patch cell suspensions. Cell suspensions prepared by teasing apart the Peyer's patches contained no adherent phagocytic cells. However, if Peyer's patch fragments were treated with collagenase to disrupt the tissue matrix, cells prepared in this way contained a subpopulation of adherent phagocytic cells. These cells comprised only 0.1-0.2% of the total nucleated cell population of the Peyer's patch. Similar cells could also be isolated from the Peyer's patches of germ-free mice, but as judged by their ability to ingest opsonized erythrocytes, these cells were less activated than cells from the Peyer's patches of normal mice. Adherent cells from the Peyer's patches of normal mice could present antigen (ovalbumin) to T cells, and Peyer's patches cell suspensions containing adherent cells could be stimulated in vitro to produce an anti-sheep red blood cell plaque-forming cell response in the absence of 2-mercaptoethanol. These studies show that although the frequency of phagocytic adherent cells is extremely low in Peyer's patches, these cells have functions consistent with that of adherent cells in other lymphoid tissues. PMID:7068173
Hernández-Ruedas, Manuel A; Arroyo-Rodríguez, Víctor; Meave, Jorge A; Martínez-Ramos, Miguel; Ibarra-Manríquez, Guillermo; Martínez, Esteban; Jamangapé, Gilberto; Melo, Felipe P L; Santos, Bráulio A
2014-01-01
Rainforests are undergoing severe deforestation and fragmentation worldwide. A huge amount of small forest patches are being created, but their value in conserving biodiversity and forest structure is still controversial. Here, we demonstrate that in a species-rich and moderately-managed Mexican tropical landscape small rainforest patches (<100 ha) can be highly valuable for the conservation of tree diversity and forest structure. These patches showed diverse communities of native plants, including endangered species, and a new record for the country. Although the number of logged trees increased in smaller patches, patch size was a poor indicator of basal area, stem density, number of species, genera and families, and community evenness. Cumulative species-area curves indicated that all patches had a similar contribution to the regional species diversity. This idea also was supported by the fact that patches strongly differed in floristic composition (high β-diversity), independently of patch size. Thus, in agreement with the land-sharing approach, our findings support that small forest patches in moderately-managed landscapes should be included in conservation initiatives to maintain landscape heterogeneity, species diversity, and ecosystem services.
Magembe, Anna J; Davis, Mark D P; Richardson, Donna M
2009-01-01
Patch testing rarely is confounded by localized dermatitis induced in the area being tested (usually the back). Its occurrence renders the interpretation of patch tests impossible. To review our experience of the circumstances in which this phenomenon occurs during patch testing. We retrospectively reviewed patients with this phenomenon who underwent patch testing from January 1, 2002, through June 30, 2006. Of the 3,569 patients tested, 12 (0.34% [9 men and 3 women]) had development of this phenomenon. All patients previously had recent widespread dermatitis that was suppressed temporarily with topical corticosteroids and wet dressings at the time of patch testing. The period between control of the dermatitis and the initiation of patch testing was less than 1 week for all patients. Three patients (25%) had recently discontinued therapy with systemic corticosteroids (less than 1 week earlier). In patients with irritable skin either immediately after widespread dermatitis is controlled or after the cessation of systemic corticosteroid treatment, a flare of dermatitis induced by patch testing may render patch tests unreadable and therefore uninterpretable. To avoid this confounding occurrence, a waiting period between control of widespread dermatitis and initiation of patch testing is advised.
Venter, Jan A; Prins, Herbert H T; Mashanova, Alla; Slotow, Rob
2017-01-01
Finding suitable forage patches in a heterogeneous landscape, where patches change dynamically both spatially and temporally could be challenging to large herbivores, especially if they have no a priori knowledge of the location of the patches. We tested whether three large grazing herbivores with a variety of different traits improve their efficiency when foraging at a heterogeneous habitat patch scale by using visual cues to gain a priori knowledge about potential higher value foraging patches. For each species (zebra ( Equus burchelli ), red hartebeest ( Alcelaphus buselaphus subspecies camaa ) and eland ( Tragelaphus oryx )), we used step lengths and directionality of movement to infer whether they were using visual cues to find suitable forage patches at a habitat patch scale. Step lengths were significantly longer for all species when moving to non-visible patches than to visible patches, but all movements showed little directionality. Of the three species, zebra movements were the most directional. Red hartebeest had the shortest step lengths and zebra the longest. We conclude that these large grazing herbivores may not exclusively use visual cues when foraging at a habitat patch scale, but would rather adapt their movement behaviour, mainly step length, to the heterogeneity of the specific landscape.
PATIENTS' KNOWLEDGE OF MEDICAL PATCHES IN HUNGARY.
Somogyi, Orsolya; Zelko, Romana
2016-11-01
Transdermal therapy with medical patches is a simple possibility in home medication. As the correct use of patches has a decisive impact from the point of its modulator effect.A questionnaire survey was developed to explore level of patients' knowledge of the correct use of transdermal patches. A survey was administered in thirteen Hungarian community pharmacies from October of 2012 to May of 2015. Most of the participants, men and women over 18 years of age (n = 233), used major analgesic patches (fentanyl); the remainder were given nitroglycerin, NSAID analgesics patches during the survey. For the hypothesis testing it was assumed that men were more likely to use a razor for skin depilation before patch application than women as their denser pelage hinders patch adhesion. The hypothesis testing showed no significant gender difference in razor use (X² = 0.201; p = 0.654). Pharmacists should direct patients to avoid using soap for skin cleansing before patch application because only 22 percent of the participants always avoided its use. Since only 9 tests were flawless from 233 completed questionnaires. Many patients do not understand how to correctly apply a transdermal dosage patch. Pharmacists should teach their correct application based on results.
A New Technique for System-to-system Transfer of Surface Data
NASA Technical Reports Server (NTRS)
Sterling, M. W.; Lucius, M. E.; Gordon, W. J.
1985-01-01
The purpose is to describe a recently developed technique aimed at providing a universal interface between surface types. In brief, a software package was developed which functions a common denominator of CAD/CAM surface types. This software enable one to convert from any given surface representation to any other target representation. The tiles maintain the same slope continuity as the target surface gram, bicubic patches are used since they allow one to match point, slope, and twist vectors to the target surface. Thus, slopes can be continuous or discontinuous as they are on the target surface. The patches can be of lower order if desired. For example, if only point information is available, the patches produced will be bilinear; however, the number of patches required is likely to increase correspondingly. The patches can be of higher order although many systems will not accept patches of more than order four. The final result of the program is a rectangular grid of bicubic patches. The patches fit the target surface exactly at their corners. Also, the patch corners have the same tangent and twist vectors. Adjacent patches will have slope continuity, unless a discontinuity was indicated by the target surface.
Yin, Chuntao; Hulbert, Scot H.; Schroeder, Kurtis L.; Mavrodi, Olga; Mavrodi, Dmitri; Dhingra, Amit; Schillinger, William F.
2013-01-01
Rhizoctonia bare patch and root rot disease of wheat, caused by Rhizoctonia solani AG-8, develops as distinct patches of stunted plants and limits the yield of direct-seeded (no-till) wheat in the Pacific Northwest of the United States. At the site of a long-term cropping systems study near Ritzville, WA, a decline in Rhizoctonia patch disease was observed over an 11-year period. Bacterial communities from bulk and rhizosphere soil of plants from inside the patches, outside the patches, and recovered patches were analyzed by using pyrosequencing with primers designed for 16S rRNA. Taxa in the class Acidobacteria and the genus Gemmatimonas were found at higher frequencies in the rhizosphere of healthy plants outside the patches than in that of diseased plants from inside the patches. Dyella and Acidobacteria subgroup Gp7 were found at higher frequencies in recovered patches. Chitinophaga, Pedobacter, Oxalobacteriaceae (Duganella and Massilia), and Chyseobacterium were found at higher frequencies in the rhizosphere of diseased plants from inside the patches. For selected taxa, trends were validated by quantitative PCR (qPCR), and observed shifts of frequencies in the rhizosphere over time were duplicated in cycling experiments in the greenhouse that involved successive plantings of wheat in Rhizoctonia-inoculated soil. Chryseobacterium soldanellicola was isolated from the rhizosphere inside the patches and exhibited significant antagonism against R. solani AG-8 in vitro and in greenhouse tests. In conclusion, we identified novel bacterial taxa that respond to conditions affecting bare patch disease symptoms and that may be involved in suppression of Rhizoctonia root rot and bare batch disease. PMID:24056471
Habitat fragmentation influences nestling growth in Mediterranean blue and great tits
NASA Astrophysics Data System (ADS)
Bueno-Enciso, Javier; Ferrer, Esperanza S.; Barrientos, Rafael; Serrano-Davies, Eva; Sanz, Juan José
2016-01-01
In patchy forest areas, the size of the forest patch where birds breed has a strong influence on their breeding success. However, the proximate effects contributing to lowering the breeding success in small forest patches remain unclear; and a shortage of crucial resources in those forest patches has been suggested to account in some degree for this failure. With the aim to further investigate this issue, we have monitored the breeding cycle of blue and great tits in three 'large' forest patches (ranging between 26.5 and 29.6 ha) and twelve 'small' forest patches (ranging between 1.1 and 2.1 ha) in a Mediterranean area in central Spain, during three years (2011-2013). We also recorded the nestling diet inside the nest-boxes with the aid of handy-cams. Only males significantly differed between forest patch size categories; being on average younger and with better body condition in small patches for great and blue tits respectively. Reproductive traits did not vary between forest patch size categories, but the body condition of blue tit nestlings and the size of great tit nestlings did, being significantly better and larger respectively in large forest patches. The recruitment rate of blue tit nestlings was also higher in large patches. Regarding nestling diet, blue tits did not differ but great tits did, delivering a larger amount of caterpillars in large forest patches. Most variation in the reproductive traits occurred between years, probably due to annual differences in environmental conditions. This study suggests that food supply could be limiting the breeding success of birds above all in small patches, but also in large patches under particular environmental conditions.
Spatial Factors in the Integration of Speed Information
NASA Technical Reports Server (NTRS)
Verghese, P.; Stone, L. S.; Hargens, Alan R. (Technical Monitor)
1995-01-01
We reported that, for a 21FC task with multiple Gabor patches in each interval, thresholds for speed discrimination decreased with the number of patches, while simply increasing the area of a single patch produced no such effect. This result could be explained by multiple patches reducing spatial uncertainty. However, the fact that thresholds decrease with number even when the patches are in fixed positions argues against this explanation. We therefore performed additional experiments to explore the lack of an area effect. Three observers did a 21FC speed discrimination task with 6 Gabor patches in each interval, and were asked to pick the interval in which the gratings moved faster. The 50% contrast patches were placed on a circle at 4 deg. eccentricity, either equally spaced and maximally separated (hexagonal array), or closely-spaced, in consecutive positions (string of pearls). For the string-of-pearls condition, the grating phases were either random, or consistent with a full-field grating viewed through multiple Gaussian windows. When grating phases were random, the thresholds for the hexagonal and string-of-pearls layouts were indistinguishable. For the string-of-pearls layout, thresholds in the consistent-phase condition were higher by 15 +/- 6% than in the random-phase condition. (Thresholds increased by 57 +/- 7% in going from 6 patches to a single patch of equivalent area.). For random-phase patches, the lower thresholds for 6 patches does not depend on a specific spacing or spatial layout. Multiple, closely-spaced, consistent-phase patches that can be interpreted as a single grating, result in thresholds closer to that produced by a single patch. Together, our results suggest that object segmentation may play a role in the integration of speed information.
NASA Astrophysics Data System (ADS)
Liu, Qingsheng; Liang, Li; Liu, Gaohuan; Huang, Chong
2017-09-01
Vegetation often exists as patch in arid and semi-arid region throughout the world. Vegetation patch can be effectively monitored by remote sensing images. However, not all satellite platforms are suitable to study quasi-circular vegetation patch. This study compares fine (GF-1) and coarse (CBERS-04) resolution platforms, specifically focusing on the quasicircular vegetation patches in the Yellow River Delta (YRD), China. Vegetation patch features (area, shape) were extracted from GF-1 and CBERS-04 imagery using unsupervised classifier (K-Means) and object-oriented approach (Example-based feature extraction with SVM classifier) in order to analyze vegetation patterns. These features were then compared using vector overlay and differencing, and the Root Mean Squared Error (RMSE) was used to determine if the mapped vegetation patches were significantly different. Regardless of K-Means or Example-based feature extraction with SVM classification, it was found that the area of quasi-circular vegetation patches from visual interpretation from QuickBird image (ground truth data) was greater than that from both of GF-1 and CBERS-04, and the number of patches detected from GF-1 data was more than that of CBERS-04 image. It was seen that without expert's experience and professional training on object-oriented approach, K-Means was better than example-based feature extraction with SVM for detecting the patch. It indicated that CBERS-04 could be used to detect the patch with area of more than 300 m2, but GF-1 data was a sufficient source for patch detection in the YRD. However, in the future, finer resolution platforms such as Worldview are needed to gain more detailed insight on patch structures and components and formation mechanism.
Upadhye, Kalpesh V.; Candiello, Joseph E.; Davidson, Lance A.; Lin, Hai
2011-01-01
Patch clamp is a powerful tool for studying the properties of ion-channels and cellular membrane. In recent years, planar patch clamp chips have been fabricated from various materials including glass, quartz, silicon, silicon nitride, polydimethyl-siloxane (PDMS), and silicon dioxide. Planar patch clamps have made automation of patch clamp recordings possible. However, most planar patch clamp chips have limitations when used in combination with other techniques. Furthermore, the fabrication methods used are often expensive and require specialized equipments. An improved design as well as fabrication and characterization of a silicon-based planar patch clamp chip are described in this report. Fabrication involves true batch fabrication processes that can be performed in most common microfabrication facilities using well established MEMS techniques. Our planar patch clamp chips can form giga-ohm seals with the cell plasma membrane with success rate comparable to existing patch clamp techniques. The chip permits whole-cell voltage clamp recordings on variety of cell types including Chinese Hamster Ovary (CHO) cells and pheochromocytoma (PC12) cells, for times longer than most available patch clamp chips. When combined with a custom microfluidics chamber, we demonstrate that it is possible to perfuse the extra-cellular as well as intra-cellular buffers. The chamber design allows integration of planar patch clamp with atomic force microscope (AFM). Using our planar patch clamp chip and microfluidics chamber, we have recorded whole-cell mechanosensitive (MS) currents produced by directly stimulating human keratinocyte (HaCaT) cells using an AFM cantilever. Our results reveal the spatial distribution of MS ion channels and temporal details of the responses from MS channels. The results show that planar patch clamp chips have great potential for multi-parametric high throughput studies of ion channel proteins. PMID:22174731
Lidocaine patches reduce pain in trauma patients with rib fractures.
Zink, Karen A; Mayberry, John C; Peck, Ellen G; Schreiber, Martin A
2011-04-01
Rib fracture pain is notoriously difficult to manage. The lidocaine patch is effective in other pain scenarios with an excellent safety profile. This study assesses the efficacy of lidocaine patches for treating rib fracture pain. A prospectively gathered cohort of patients with rib fracture was retrospectively analyzed for use of lidocaine patches. Patients treated with lidocaine patches were matched to control subjects treated without patches. Subjective pain reports and narcotic use before and after patch placement, or equivalent time points for control subjects, were gathered from the chart. All patients underwent long-term follow-up, including a McGill Pain Questionnaire (MPQ). Twenty-nine patients with lidocaine patches (LP) and 29 matched control subjects (C) were analyzed. During the 24 hours before patch placement, pain scores and narcotic use were similar (LP 5.3, C 4.6, P = 0.19 and LP 51, C 32 mg morphine, P = 0.17). In the 24 hours after patch placement, LP patients had a greater decrease in pain scores (LP 1.2, C 0.0, P = 0.01) with no change in narcotic use (LP -8.4, C 0.5-mg change in morphine, P = 0.25). At 60 days, LP patients had a lower MPQ pain score (LP 7.7, C 12.2, P < 0.01), although only one patient was still using a patch. There was no difference in time to return to baseline activity (LP 73, C 105 days, P = 0.16) and no adverse events. Lidocaine patches are a safe, effective adjunct for rib fracture pain. Lidocaine patches resulted in a sustained reduction in pain, outlasting the duration of therapy.
Macronutrient balancing affects patch departure by guerezas (Colobus guereza).
Johnson, Caley A; Raubenheimer, David; Chapman, Colin A; Tombak, Kaia J; Reid, Andrea J; Rothman, Jessica M
2017-04-01
Foraging strategies are central in shaping social structure and grouping patterns in primates. We address Colobus guereza foraging strategies by investigating their patch departure decisions in relation to diet composition and nutrition. We examine whether guerezas are constrained in their intake of food in patches and thereby forage according to a fixed amount strategy that dictates patch departure. Additionally, we assess whether guereza employ a fixed time strategy or attempt to balance nutrients when foraging. We measured food patch occupancy time, intake rates, and analyzed foods for macronutrients, fiber, and condensed tannins. We determined that guerezas do not employ a fixed time foraging strategy; patch residence time varied widely between 1 and 290 min. They also did not depart patches or stop eating when they reached a specific intake of dry mass, macronutrients, or condensed tannins. However, guerezas maintained a macronutrient balance when feeding across patches, and the balance of protein to non-protein energy (fats and carbohydrates) in patches is the best indicator of time adult guerezas spent feeding in patches. Previous studies have shown that the protein-to-fiber ratio is important in predicting food selection for folivores and their biomass; however, we found that guerezas did not maximize protein and minimize fiber intake while foraging in patches, nor did they stay longer in patches with the highest ratio of protein to fiber concentrations. This study raises questions about the nutritional and social implications of patch depletion as a foraging strategy in folivorous monkeys where food limitation predicts competitive and social regimes. Am. J. Primatol. 79:e22495, 2017. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
Agervi, Pia; Kugelberg, Ulla; Kugelberg, Maria; Zetterström, Charlotta
2013-11-01
To compare spectacles plus alternate-day patching for 8 hr or more with spectacles plus patching for 8 hr or more 6 days weekly to treat strabismic amblyopia 1 year after a 1-year randomized trial. Forty children (mean age, 4.3 years) participated. Refractive correction was provided. The children were assigned to alternate-day patching for 8 hr or more or patching for 8 hr or more daily 6 days weekly. VA, binocular function, and refractive errors were measured after 2 years. The main outcome measure was the median VA change in the amblyopic eye after 2 years. The median VA change in the amblyopic eye at the 2-year visit was significantly (p = 0.0453) greater with alternate-day patching (0.8 log unit) versus patching daily 6 days weekly (0.6 log unit). The final median VA in the amblyopic eyes was 0.0 logMAR in the alternate-day patching group and 0.1 logMAR in the daily patching group. Binocular function improved with both treatments. The median spherical equivalent (SE) refractive error increased in the fellow eyes (alternate-day patching, p < 0.0001; patching daily 6 days weekly, p = 0.0033); no change was found in the amblyopic eyes in either group. The magnitude of the VA change 2 years after treatment with spectacles plus alternate-day patching for 8 hr or more was significantly greater than with spectacles plus daily patching for 8 hr or more 6 days weekly for strabismic amblyopia. However, the final median VA did not differ significantly between the two treatments. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.
Treatment of Neuropathic Pain with the Capsaicin 8% Patch: Is Pretreatment with Lidocaine Necessary?
Kern, Kai-Uwe; Nowack, Walburga; Poole, Chris
2014-01-01
The capsaicin 8% patch can effectively treat neuropathic pain, but application can cause discomfort or a burning sensation. Until March 2013, it was recommended that patients be pretreated with a topical anesthetic, for example lidocaine, before capsaicin patch application. However, speculation existed over the need for pretreatment and its effectiveness in alleviating treatment-associated discomfort. This article compares tolerability to and efficacy of the capsaicin patch in pretreated and non-pretreated patients. All patients received a single capsaicin patch application. Pretreated patients received a lidocaine plaster before and intravenous lidocaine and metamizole infusions during capsaicin patch application. Pain levels, assessed using a Numeric Rating Scale (NRS), were used to determine tolerability and efficacy. All patients (pretreated n = 32; non-pretreated n = 26) completed 100% of the intended capsaicin patch application duration. At the time of capsaicin patch removal, 69% of pretreated and 88% of non-pretreated patients reported an NRS score increase, which returned to baseline by 6 hours post-treatment. There was no significant difference in mean NRS score between patient groups at any time during or after capsaicin patch treatment. Response was similar between patient groups; capsaicin patch treatment provided rapid and significant pain reductions that were sustained over 12 weeks. The same proportion of pretreated and non-pretreated patients reported willingness to receive retreatment with the capsaicin patch. This analysis shows that the capsaicin 8% patch is generally tolerable, and the small discomfort associated with patch application is short-lived. Lidocaine pretreatment does not have a significant effect on tolerability, efficacy, or patient willingness to receive retreatment. PMID:24289500
Coevolution of patch-type dependent emigration and patch-type dependent immigration.
Weigang, Helene C
2017-08-07
The three phases of dispersal - emigration, transfer and immigration - are affecting each other and the former and latter decisions may depend on patch types. Despite the inevitable fact of the complexity of the dispersal process, patch-type dependencies of dispersal decisions modelled as emigration and immigration are usually missing in theoretical dispersal models. Here, I investigate the coevolution of patch-type dependent emigration and patch-type dependent immigration in an extended Hamilton-May model. The dispersing population inhabits a landscape structured into many patches of two types and disperses during a continuous-time season. The trait under consideration is a four dimensional vector consisting of two values for emigration probability from the patches and two values for immigration probability into the patches of each type. Using the adaptive dynamics approach I show that four qualitatively different dispersal strategies may evolve in different parameter regions, including a counterintuitive strategy, where patches of one type are fully dispersed from (emigration probability is one) but individuals nevertheless always immigrate into them during the dispersal season (immigration probability is one). I present examples of evolutionary branching in a wide parameter range, when the patches with high local death rate during the dispersal season guarantee a high expected disperser output. I find that two dispersal strategies can coexist after evolutionary branching: a strategy with full immigration only into the patches with high expected disperser output coexists with a strategy that immigrates into any patch. Stochastic simulations agree with the numerical predictions. Since evolutionary branching is also found when immigration evolves alone, the present study is adding coevolutionary constraints on the emigration traits and hence finds that the coevolution of a higher dimensional trait sometimes hinders evolutionary diversification. Copyright © 2017 Elsevier Ltd. All rights reserved.
... patch. Each patch is stuck onto a thin plastic liner and a separate rigid plastic film. Do not open the pouch in advance, ... cut the patch into pieces. Peel the thin plastic liner off of the printed side of the ...
... It works by stopping nerves from sending pain signals. ... time and the length of time you may wear the patches. Never apply more than three patches at one time, and never wear patches for more than 12 hours per day. ...
Percutaneous fetoscopic closure of large open spina bifida using a bilaminar skin substitute.
Lapa Pedreira, Denise A; Acacio, Gregório L; Gonçalves, Rodrigo T; Sá, Renato Augusto M; Brandt, Reynaldo A; Chmait, Ramen; Kontopoulos, Eftichia; Quintero, Ruben A
2018-01-04
We have previously described our percutaneous fetoscopic technique for the treatment of open spina bifida (OSB). However, approximately 20-30% of OSB defects are too large to allow primary skin closure. We hereby describe a modification of our standard technique using a bilaminar skin substitute to allow closure of such large spinal defects. The aim of this study was to report our clinical experience with the use of a bilaminar skin substitute and a percutaneous fetoscopic technique for the prenatal closure of large spina bifida defects. Surgeries were performed between 24.0 and 28.9 gestational weeks under general anesthesia, using an entirely percutaneous fetoscopic approach with partial CO2 insufflation of the uterine cavity, as previously described. If there was enough skin to be sutured in the midline, only a biocellulose patch was placed over the placode. In cases where skin approximation was not possible, a bilaminar skin substitute (two layers: one silicone and one dermal matrix) was placed over the biocellulose. The surgical site was assessed at birth, and long-term follow-up was performed. Forty-seven consecutive fetuses underwent percutaneous fetoscopic OSB repair. Premature preterm rupture of membranes (PPROM) occurred in 38 (84%), and the mean gestational age at delivery was 32,8 + 2.5 weeks. A bilaminar skin substitute was required in 13 (29%), of which 5 was associated with myeloschisis. In all cases the skin substitute was found at the surgical site, at birth. In 3 (15%) of these cases, postnatal additional repair was needed. In the other 10 cases, the silicone layer detached spontaneously from the dermal matrix (average 25 days after birth), and the lesion healed by secondary-intention. Operating time was significantly longer in cases requiring the bilaminar skin substitute (additional 42 minutes). The subgroup with bilaminar skin substitute had similar PPROM rate and delivery gestational age compared to the one patch group. Complete reversal of hindbrain herniation occurred in 68% of the one patch and in 33% (p < 0.05) of the two patches group. In 4 cases there was no reversal and 3 of them were myeloschisis cases. Large OSB defects may be successfully treated in utero using a bilaminar skin substitute over a biocellulose patch through an entirely percutaneous approach. Although the operating time is longer, surgical outcomes are similar to cases closed primarily. Myeloschisis seems to have a worse prognosis then myelomeningocele cases. PPROM and preterm birth continue to be a challenge. Further experience is needed to assess the risks and benefits of this technique for management of large OSB defects. This article is protected by copyright. All rights reserved.
LQR Control of Shell Vibrations Via Piezoceramic Actuators
NASA Technical Reports Server (NTRS)
delRosario, R. C. H.; Smith, R. C.
1997-01-01
A model-based Linear Quadratic Regulator (LQR) method for controlling vibrations in cylindrical shells is presented. Surface-mounted piezo-ceramic patches are employed as actuators which leads to unbounded control input operators. Modified Donnell-Mushtari shell equations incorporating strong or Kelvin-Voigt damping are used to model the system. The model is then abstractly formulated in terms of sesquilinear forms. This provides a framework amenable for proving model well-posedness and convergence of LQR gains using analytic semigroup results combined with LQR theory for unbounded input operators. Finally, numerical examples demonstrating the effectiveness of the method are presented.
1955-01-01
recent operations of the Allied carrier and shore based aircraft. As has been pointed out in Volume I this had affected the Japanese economy and the...SERIOUSLY AFFECTED BY THE MESSAGES LISTED UNDER "BASIC INSTRUCTIONS BY DIS- PATCH", REFERRED TO AB(OVE. IT IS VERY LIKELY THAT HE DID NOT REALIZE THAT...71.1 WHICH INCLUDED THE BREAM. IT SEEMS LIKELY THAT HE HAD BEEN AFFECTED BY THE CONCEPT THAT NO MAJOR ELEMENTS OF THE JAPANESE FLEET WOULD BE 1NVOLVED
A disorder-based strategy for tunable, broadband wave attenuation
NASA Astrophysics Data System (ADS)
Zhang, Weiting; Celli, Paolo; Cardella, Davide; Gonella, Stefano
2017-04-01
One of the most daunting limitations of phononic crystals and acoustic/elastic metamaterials is their passivity: a given configuration is bound to display its phononic properties only around its design point, i.e., working at some pre-determined operating conditions. In the past decade, this shortcoming has inspired the design of phononic media with tunable wave characteristics; noteworthy results have been obtained through a family of methodologies involving shunted piezoelectric elements. Shunting a piezoelectric element means connecting it to a passive electric circuit; tunability stems from the ability to modify the effective mechanical properties of the piezoelectric medium by modifying the circuit characteristics. One of the most popular shunting circuits is the resistor-inductor, which allows the patch-and-shunt system to behave as an electromechanical resonator. A common motif among the works employing shunted piezos for phononic control is periodicity: the patches are typically periodically placed in the domain and the circuits are identically tuned. The objective of this work is to demonstrate that the wave attenuation performance of structures with shunted piezoelectric patches can be improved by leveraging notions of organized disorder. Based on the idea of rainbow trapping broadband wave attenuation obtained by tuning an array of resonators at distinct neighboring frequencies we design and test an electromechanical waveguide structure capable of attenuating waves over broad frequency ranges. In order to emphasize the fact that periodicity is not a binding requirement when working with RL shunts (which induce locally resonant bandgaps), we report on the performance of random arrangements of patches. In an attempt to demonstrate the tunability attribute of our strategy, we take advantage of the reconfigurability of the circuits to show how a single waveguide can attenuate both waves and vibrations over different frequency ranges.
Naveed, Muhammad; Han, Lei; Khan, Ghulam Jilany; Yasmeen, Sufia; Mikrani, Reyaj; Abbas, Muhammad; Cunyu, Li; Xiaohui, Zhou
2018-06-01
Congestive heart failure (CHF) is a complicated pathophysiological syndrome, leading cause of hospitalization as well as mortalities in developed countries wherein an irregular function of the heart leads to the insufficient blood supply to the body organs. It is an accumulative slackening of various complications including myocardial infarction (MI), coronary heart disease (CAD), hypertension, valvular heart disease (VHD) and cardiomyopathy; its hallmarks include hypertrophy, increased interstitial fibrosis and loss of myocytes. The etiology of CHF is very complex and despite the rapid advancement in pharmacological and device-based interventional therapies still, a single therapy may not be sufficient to meet the demand for coping with the diseases. Total artificial hearts (TAH) and ventricular assist devices (VADs) have been widely used clinically to assist patients with severe HF. Unfortunately, direct contact between the patient's blood and device leads to thromboembolic events, and then coagulatory factors, as well as, infection contribute significantly to complicate the situation. There is no effective treatment of HF except cardiac transplantation, however, genetic variations, tissue mismatch; differences in certain immune response and socioeconomic crisis are an important concern with cardiac transplantation suggesting an alternate bridge to transplant (BTT) or destination therapies (DT). For these reasons, researchers have turned to mechanically driven compression devices, ventricular restraint devices (VRD) and heart patches. The ASD is a combination of all operational patches and cardiac support devices (CSD) by delivering biological agents and can restrain or compress the heart. Present study summarizes the accessible peer-reviewed literature focusing on the mechanism of Direct Cardiac Compression (DCC) devices, VRD and patches and their acquaintance to optimize the therapeutic efficacy in a synergistic way. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Law, Amy; Lee, Yi-Chien; Gorritz, Magdaliz; Plouffe, Leo
2014-08-01
This study evaluated contraceptive refill patterns of women insured commercially in the US who switched from oral contraceptives (OCs) to the patch or vaginal ring and assessed if switching contraceptive methods changes refill patterns. Women aged 15-44 with ≥2 patch or ring prescriptions and ≥2 OC prescriptions before the first patch/ring prescription were identified from the MarketScan® Commercial database (1/1/2002-6/30/2011). Refill patterns 1-year pre- and postindex date (first patch/ring prescription) were evaluated, and women were categorized as timely or delayed refillers on OCs and patch/ring. Regression modeling was used to investigate the association between refill patterns and contraceptive methods and switching effects on refill patterns. Of 17,814 women identified, 7901 switched to the patch, and 9913 switched to the ring. Among timely OC refillers, the percentage of timely refills decreased (patch: 95.6% to 79.4%, p<.001; ring: 96.5% to 74.3%, p<.001). However, among delayed OC refillers, the percentage of timely refills improved (patch: 47.9% to 72.2%, p<.001; ring: 50.4% to 64.0%, p<.001) during patch/ring use. Nonetheless, compared to timely OC refillers, women who were delayed OC refillers had 1.68-fold [95% confidence interval (CI): 1.52-1.84, p<.001] and 1.85-fold greater odds (CI: 1.69-2.02, p<.001) of being a delayed refiller while on the patch and ring, respectively. Switching to the patch or ring may improve refill behavior for women who have problems refilling OCs timely; however, the magnitude of the improvement may fail to improve ultimate contraceptive efficacy by simply switching to the patch or ring. The impact on timely refills of switching from OCs to either the patch or ring is complex and varies depending on the pattern of timely refills on OCs. Copyright © 2014 Elsevier Inc. All rights reserved.
Kartzinel, Tyler R.; Hamrick, J. L.; Wang, Chongyun; Bowsher, Alan W.; Quigley, Bryan G. P.
2015-01-01
Background and Aims Viny species are among the most serious invasive plants, and better knowledge of how vines grow to dominate landscapes is needed. Patches may contain a single genotype (i.e. genet), a competitively dominant genet or many independent but interacting genets, yet the clonal structure of vining species is often not apparent. Molecular markers can discriminate among the genetic identities of entwined vines to reveal the number and spatial distribution of genets. This study investigated how genets are spatially distributed within and among discrete patches of the invasive vine kudzu, Pueraria montana var. lobata, in the United States. It was expected that ramets of genets would be spatially clustered within patches, and that an increase in the number of genets within a patch would be associated with a decrease in the average size of each genet. Methods Six discrete kudzu patches were sampled across 2 years, and 1257 samples were genotyped at 21 polymorphic allozyme loci. Variation in genotypic and genetic diversity among patches was quantified and patterns of genet interdigitation were analysed. Key Results Substantial genotypic and genetic variation occurred within and among patches. As few as ten overlapping genets spanned up to 68 m2 in one patch, while >90 % of samples were genetically unique in another patch. Genotypic diversity within patches increased as mean clone size decreased, although spatially widespread genets did not preclude interdigitation. Eight genets were shared across ≥2 patches, suggesting that vegetative dispersal can occur among patches. Conclusions Genetically unique kudzu vines are highly interdigitated. Multiple vegetative propagules have become established in spatially discrete patches, probably through the movement of highway construction or maintenance machinery. The results suggest that common methods for controlling invasive vines (e.g. mowing) may inadvertently increase genotypic diversity. Thus, understanding vine architecture and growth has practical implications. PMID:26229064
Effects of Intra- and Interpatch Host Density on Egg Parasitism by Three Species of Trichogramma
Grieshop, Matthew J.; Flinn, Paul W.; Nechols, James R.
2010-01-01
Host-foraging responses to different intra- and interpatch densities were used to assess three Trichogramma spp. (Hymenoptera: Trichogrammatidae) Trichogramma deion Pinto and Oatman, T. ostriniae Pang and Chen, and T. pretiosum Riley — as potential biological control agents for the Indian meal moth, Plodia interpunctella Hübner (Lepidoptera: Pyralidae). Single naïve females were allowed 6 h to forage in Plexiglas arenas with four different spatial arrangements of host eggs, nine single-egg patches), nine four-egg patches, 36 single-egg patches, and 36 four-egg patches. No significant differences were found among species in the number of patches parasitized. As expected, all three species parasitized the most eggs in the 36 four-egg patch treatment and the least in the nine single-egg patch treatment. T. deion parasitized significantly more eggs than T. pretiosum on the nine four-egg patches. T. ostriniae parasitized significantly more patches when intrapatch density was greater, regardless of interpatch density. In contrast, T. deion only parasitized more patches at the greater intrapatch density when the interpatch density was low. Patch density had no effect on T. pretiosum. The spatial pattern of parasitism was more aggregated for T. deion and T. ostriniae in the 36 four-egg patches treatment compared to the 36 single-egg patches treatment. Therefore, intrapatch density was more important than interpatch density for T. ostriniae, and potentially for T. deion, but not for T. pretiosum. T. deion may be the best candidate for augmentative biological control because it parasitized either slightly or significantly more eggs than the other two species in all four treatments. Furthermore, the pattern of parasitism by T. deion in the 36 four-egg patches treatment was the most aggregated among the three species, suggesting a more thorough searching pattern. In contrast, T. pretiosum had the least aggregated pattern of parasitism and therefore may have used a more random foraging pattern. PMID:20673123
Effects of intra- and interpatch host density on egg parasitism by three species of Trichogramma.
Grieshop, Matthew J; Flinn, Paul W; Nechols, James R
2010-01-01
Host-foraging responses to different intra- and interpatch densities were used to assess three Trichogramma spp. (Hymenoptera: Trichogrammatidae) Trichogramma deion Pinto and Oatman, T. ostriniae Pang and Chen, and T. pretiosum Riley - as potential biological control agents for the Indian meal moth, Plodia interpunctella Hübner (Lepidoptera: Pyralidae). Single naïve females were allowed 6 h to forage in Plexiglas arenas with four different spatial arrangements of host eggs, nine single-egg patches), nine four-egg patches, 36 single-egg patches, and 36 four-egg patches. No significant differences were found among species in the number of patches parasitized. As expected, all three species parasitized the most eggs in the 36 four-egg patch treatment and the least in the nine single-egg patch treatment. T. deion parasitized significantly more eggs than T. pretiosum on the nine four-egg patches. T. ostriniae parasitized significantly more patches when intrapatch density was greater, regardless of interpatch density. In contrast, T. deion only parasitized more patches at the greater intrapatch density when the interpatch density was low. Patch density had no effect on T. pretiosum. The spatial pattern of parasitism was more aggregated for T. deion and T. ostriniae in the 36 four-egg patches treatment compared to the 36 single-egg patches treatment. Therefore, intrapatch density was more important than interpatch density for T. ostriniae, and potentially for T. deion, but not for T. pretiosum. T. deion may be the best candidate for augmentative biological control because it parasitized either slightly or significantly more eggs than the other two species in all four treatments. Furthermore, the pattern of parasitism by T. deion in the 36 four-egg patches treatment was the most aggregated among the three species, suggesting a more thorough searching pattern. In contrast, T. pretiosum had the least aggregated pattern of parasitism and therefore may have used a more random foraging pattern.
Manna, F; Pradel, R; Choquet, R; Fréville, H; Cheptou, P-O
2017-10-01
In plants, the presence of a seed bank challenges the application of classical metapopulation models to aboveground presence surveys; ignoring seed bank leads to overestimated extinction and colonization rates. In this article, we explore the possibility to detect seed bank using hidden Markov models in the analysis of aboveground patch occupancy surveys of an annual plant with limited dispersal. Patch occupancy data were generated by simulation under two metapopulation sizes (N = 200 and N = 1,000 patches) and different metapopulation scenarios, each scenario being a combination of the presence/absence of a 1-yr seed bank and the presence/absence of limited dispersal in a circular 1-dimension configuration of patches. In addition, because local conditions often vary among patches in natural metapopulations, we simulated patch occupancy data with heterogeneous germination rate and patch disturbance. Seed bank is not observable from aboveground patch occupancy surveys, hence hidden Markov models were designed to account for uncertainty in patch occupancy. We explored their ability to retrieve the correct scenario. For 10 yr surveys and metapopulation sizes of N = 200 or 1,000 patches, the correct metapopulation scenario was detected at a rate close to 100%, whatever the underlying scenario considered. For smaller, more realistic, survey duration, the length for a reliable detection of the correct scenario depends on the metapopulation size: 3 yr for N = 1,000 and 6 yr for N = 200 are enough. Our method remained powerful to disentangle seed bank from dispersal in the presence of patch heterogeneity affecting either seed germination or patch extinction. Our work shows that seed bank and limited dispersal generate different signatures on aboveground patch occupancy surveys. Therefore, our method provides a powerful tool to infer metapopulation dynamics in a wide range of species with an undetectable life form. © 2017 by the Ecological Society of America.
Patch-based Convolutional Neural Network for Whole Slide Tissue Image Classification
Hou, Le; Samaras, Dimitris; Kurc, Tahsin M.; Gao, Yi; Davis, James E.; Saltz, Joel H.
2016-01-01
Convolutional Neural Networks (CNN) are state-of-the-art models for many image classification tasks. However, to recognize cancer subtypes automatically, training a CNN on gigapixel resolution Whole Slide Tissue Images (WSI) is currently computationally impossible. The differentiation of cancer subtypes is based on cellular-level visual features observed on image patch scale. Therefore, we argue that in this situation, training a patch-level classifier on image patches will perform better than or similar to an image-level classifier. The challenge becomes how to intelligently combine patch-level classification results and model the fact that not all patches will be discriminative. We propose to train a decision fusion model to aggregate patch-level predictions given by patch-level CNNs, which to the best of our knowledge has not been shown before. Furthermore, we formulate a novel Expectation-Maximization (EM) based method that automatically locates discriminative patches robustly by utilizing the spatial relationships of patches. We apply our method to the classification of glioma and non-small-cell lung carcinoma cases into subtypes. The classification accuracy of our method is similar to the inter-observer agreement between pathologists. Although it is impossible to train CNNs on WSIs, we experimentally demonstrate using a comparable non-cancer dataset of smaller images that a patch-based CNN can outperform an image-based CNN. PMID:27795661
Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal
2016-01-01
In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, free-standing electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on-demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function. PMID:26974408
Matsumoto, H; Oguchi, Y; Miyake, Y; Masuda, Y; Masada, S; Kuno, Y; Shibahara, I; Takashima, K; Yamane, H; Yamagata, S; Noishiki, Y; Yamane, Y
1996-07-01
Canine pericardium which had been treated with polyepoxy compounds (Denacol EX-313) was used as a patch graft for the correction of experimentally-created diaphragmatic defects in five dogs belonging to the same litter. Clinical, macroscopic and histological examinations were conducted every month up to five months after suturing of the patch graft. Clinical examination of the patch graft showed no apparent abnormalities. Macroscopic examination conducted during autopsy showed that the patch graft maintained adequate elasticity for five months after suturing, the surface of the patch graft was covered with a thin membrane and neovascularization was observed. Histological examination showed that the surface of the patch graft was covered with a thin membrane. Inflammatory tissue reactions were observed at one month, but gradually decreased from the second month onwards. In addition, the patch graft had excellent tissue affinity.
The modeling of piezoceramic patch interactions with shells, plates and beams
NASA Technical Reports Server (NTRS)
Banks, H. T.; Smith, R. C.
1992-01-01
General models describing the interactions between a pair of piezoceramic patches and elastic substructures consisting of a cylindrical shell, plate and beam are presented. In each case, the manner in which the patch loads enter both the strong and weak forms of the time-dependent structural equations of motion is described. Through force and moment balancing, these loads are then determined in terms of material properties of the patch and substructure (thickness, elastic properties, Poisson ratios), the geometry of the patch placement, and the voltages into the patches. In the case of the shell, the coupling between banding and inplane deformations, which is due to the curvature, is retained. These models are sufficiently general to allow for potentially different patch voltages which implies that they can be suitably employed when using piezoceramic patches for controlling system dynamics when both extensional and bending vibrations are present.
Feiner, Ron; Engel, Leeya; Fleischer, Sharon; Malki, Maayan; Gal, Idan; Shapira, Assaf; Shacham-Diamand, Yosi; Dvir, Tal
2016-06-01
In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells are seeded within three-dimensional porous scaffolds to create functional cardiac patches. However, current cardiac patches do not allow for online monitoring and reporting of engineered-tissue performance, and do not interfere to deliver signals for patch activation or to enable its integration with the host. Here, we report an engineered cardiac patch that integrates cardiac cells with flexible, freestanding electronics and a 3D nanocomposite scaffold. The patch exhibited robust electronic properties, enabling the recording of cellular electrical activities and the on-demand provision of electrical stimulation for synchronizing cell contraction. We also show that electroactive polymers containing biological factors can be deposited on designated electrodes to release drugs in the patch microenvironment on demand. We expect that the integration of complex electronics within cardiac patches will eventually provide therapeutic control and regulation of cardiac function.
Density of adult Diadema antillarum was assessed on live coral patch reefs and dead Acropora cervicornis rubble patches next to Loggerhead Key, Dry Tortugas National Park, Florida, USA in June 2009. Mean density on live coral patch reefs (0.49 individuals m-2) was not statistical...
Improved Gain Microstrip Patch Antenna
2015-08-06
08-2015 Publication Improved Gain Microstrip Patch Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L...GAIN MICROSTRIP PATCH ANTENNA STATEMENT OF GOVERNMENT INTEREST [0001] The invention described herein may be manufactured and used by or for the...patch antenna having increased gain, and an apparatus for increasing the gain and bandwidth of an existing microstrip patch antenna . (2) Description
Buccal patches of atenolol formulated using fenugreek (Trigonella foenum-graecum L.) seed mucilage.
Adhikari, Surya Narayan Ratha; Panda, Satyabrata
2017-01-01
The use of mucoadhesive natural polymers in designing mucoadhesive patch systems has received much attention. The study involved the development and evaluation of buccal patches of atenolol using fenugreek (Trigonella foenum-graecum L.) seed mucilage with hydroxylpropyl methyl cellulose (HPMC K4M) and a backing membrane (ethyl cellulose 5% w/v). These atenolol-releasing buccal patches were prepared using a solvent casting technique. The buccal patches prepared were evaluated for average weight, thickness, drug content, folding endurance and moisture content. Ex vivo mucoadhesive strength, force of adhesion and bonding strength were determined using porcine buccal mucosa. The mucosal permeation of atenolol through the porcine buccal mucosa was carried out using a Franz diffusion cell in phosphate buffer saline, pH 6.8. These buccal patches were also characterized by SEM and FTIR spectroscopy. The average weight, thickness, drug content, folding endurance and moisture content of these atenolol-releasing buccal patches were found satisfactory for all the patches. Amongst all, the F-4 buccal patch showed maximum mucoadhesive strength (31.12 ±1.86 g), force of adhesion (30.53 × 10-2 N) and bond strength (1748.89 N/m2). Ex vivo atenolol permeation from the buccal patches showed drug permeation across the excised porcine buccal mucosa over 12 h. The F-4 buccal patch showed maximum permeation flux (29.12 μg/cm2/h). The developed atenolol-releasing buccal patches can be beneficial over the conventional drug delivery systems to decrease the dosing frequency and enhance patient compliance.
Dye-enhanced protein solders and patches in laser-assisted tissue welding.
Small, W; Heredia, N J; Maitland, D J; Da Silva, L B; Matthews, D L
1997-01-01
This study examines the use of dye-enhanced protein bonding agents in 805 nm diode laser-assisted tissue welding. A comparison of an albumin liquid solder and collagen solid-matrix patches used to repair arteriotomies in an in vitro porcine model is presented. Extrinsic bonding media in the form of solders and patches have been used to enhance the practice of laser tissue welding. Preferential absorption of the laser wavelength has been achieved by the incorporation of chromophores. Both the solder and the patch included indocyanine green dye (ICG) to absorb the 805 nm continuous-wave diode laser light used to perform the welds. Solder-mediated welds were divided into two groups (high power/short exposure and low power/long exposure), and the patches were divided into three thickness groups ranging from 0.1 to 1.3 mm. The power used to activate the patches was constant, but the exposure time was increased with patch thickness. Burst pressure results indicated that solder-mediated and patched welds yielded similar average burst strengths in most cases, but the patches provided a higher success rate (i.e., more often exceeded 150 mmHg) and were more consistent (i.e., smaller standard deviation) than the solder. The strongest welds were obtained using 1.0-1.3 mm thick patches, while the high power/short exposure solder group was the weakest. Though the solder and patches yielded similar acute weld strengths, the solid-matrix patches facilitated the welding process and provided consistently strong welds. The material properties of the extrinsic agents influenced their performance.
Does body size affect a bird's sensitivity to patch size and landscape structure?
Winter, Maiken; Johnson, Douglas H.; Shaffer, Jill A.
2006-01-01
Larger birds are generally more strongly affected by habitat loss and fragmentation than are smaller ones because they require more resources and thus larger habitat patches. Consequently, conservation actions often favor the creation or protection of larger over smaller patches. However, in grassland systems the boundaries between a patch and the surrounding landscape, and thus the perceived size of a patch, can be indistinct. We investigated whether eight grassland bird species with different body sizes perceived variation in patch size and landscape structure in a consistent manner. Data were collected from surveys conducted in 44 patches of northern tallgrass prairie during 1998–2001. The response to patch size was very similar among species regardless of body size (density was little affected by patch size), except in the Greater Prairie-Chicken (Tympanuchus cupido), which showed a threshold effect and was not found in patches smaller than 140 ha. In landscapes containing 0%–30% woody vegetation, smaller species responded more negatively to increases in the percentage of woody vegetation than larger species, but above an apparent threshold of 30%, larger species were not detected. Further analyses revealed that the observed variation in responses to patch size and landscape structure among species was not solely due to body size per se, but to other differences among species. These results indicate that a stringent application of concepts requiring larger habitat patches for larger species appears to limit the number of grassland habitats that can be protected and may not always be the most effective conservation strategy.
Grundel, R.; Pavlovic, N.B.
2007-01-01
Determination of which aspects of habitat quality and habitat spatial arrangement best account for variation in a species’ distribution can guide management for organisms such as the Karner blue butterfly (Lycaeides melissa samuelis), a federally endangered subspecies inhabiting savannas of Midwest and Eastern United States. We examined the extent to which three sets of predictors, (1) larval host plant (Lupinus perennis, wild lupine) availability, (2) characteristics of the matrix surrounding host plant patches, and (3) factors affecting a patch’s thermal environment, accounted for variation in lupine patch use by Karner blues at Indiana Dunes National Lakeshore, Indiana and Fort McCoy, Wisconsin, USA. Each predictor set accounted for 7–13% of variation in patch occupancy by Karner blues at both sites and in larval feeding activity among patches at Indiana Dunes. Patch area, an indicator of host plant availability, was an exception, accounting for 30% of variation in patch occupancy at Indiana Dunes. Spatially structured patterns of patch use across the landscape accounted for 9–16% of variation in patch use and explained more variation in larval feeding activity than did spatial autocorrelation between neighboring patches. Because of this broader spatial trend across sites, a given management action may be more effective in promoting patch use in some portions of the landscape than in others. Spatial trend, resource availability, matrix quality, and microclimate, in general, accounted for similar amounts of variation in patch use and each should be incorporated into habitat management planning for the Karner blue butterfly.
Predation-related odours reduce oviposition in a herbivorous mite.
Choh, Yasuyuki; Uefune, Masayoshi; Takabayashi, Junji
2010-01-01
When adult females of the herbivorous mite, Tetranychus urticae, were exposed to the predatory mite, Phytoseiulus persimilis, they laid fewer eggs than females that had not been exposed to P. persimilis when transferred onto a new leaf patch. However, when T. urticae females were exposed to either products of P. persimilis or artificially damaged conspecific eggs on a leaf patch, the number of T. urticae eggs on a new leaf patch did not differ significantly from the control. The reduced oviposition was neither due to the feeding activity on the leaf patch with P. persimilis nor to that on the new leaf patch. There was also no significant difference between the number of T. urticae eggs produced on a new leaf patch following exposure to the odours of a neighbouring leaf patch where there had previously been either P. persimilis or T. urticae adults. However, female T. urticae that had been exposed to odours from neighbouring leaf patches on which both T. urticae and P. persimilis had been placed produced significantly fewer eggs on a new leaf patch than those that had not been exposed to such odours. Neither odours from neighbouring intact leaf patches on which T. urticae eggs were preyed on by P. persimilis, nor odours from a neighbouring Parafilm patch on which T. urticae was preyed on by P. persimilis affected the oviposition of T. urticae. These data suggest that the presence of T. urticae, P. persimilis and a leaf patch are needed for the emission of odours to reduce oviposition in T. urticae.
Transdermal patches: history, development and pharmacology.
Pastore, Michael N; Kalia, Yogeshvar N; Horstmann, Michael; Roberts, Michael S
2015-05-01
Transdermal patches are now widely used as cosmetic, topical and transdermal delivery systems. These patches represent a key outcome from the growth in skin science, technology and expertise developed through trial and error, clinical observation and evidence-based studies that date back to the first existing human records. This review begins with the earliest topical therapies and traces topical delivery to the present-day transdermal patches, describing along the way the initial trials, devices and drug delivery systems that underpin current transdermal patches and their actives. This is followed by consideration of the evolution in the various patch designs and their limitations as well as requirements for actives to be used for transdermal delivery. The properties of and issues associated with the use of currently marketed products, such as variability, safety and regulatory aspects, are then described. The review concludes by examining future prospects for transdermal patches and drug delivery systems, such as the combination of active delivery systems with patches, minimally invasive microneedle patches and cutaneous solutions, including metered-dose systems. © 2015 The British Pharmacological Society.
... Safe Videos for Educators Search English Español Birth Control Patch KidsHealth / For Teens / Birth Control Patch What's in this article? What Is It? ... It Cost? Print What Is It? The birth control patch is a thin, beige, 1¾-inch (4½- ...
1988-11-01
Bilayer ........................................... 14 5. Current-Voltage Curve for Gramacidin in a Lecithin -Sphingomyelin Patch Bilayer... lecithin (Avanti). 9 2. MATERIALS 2.1 Patch Microprobe Instrumentation. The basis of the microprobe system is an AxoPatch Patch- Clamping Amplifier System...histogram of 1024 events cut above 2 pA. Events sampled are thought to be from the same single gramacidin channel in a lecithin : sphingomyelin (5:1) patch
Patch Test Negative Generalized Dermatitis.
Spiker, Alison; Mowad, Christen
2016-01-01
Allergic contact dermatitis is a common condition in dermatology. Patch testing is the criterion standard for diagnosis. However, dermatitis is not always caused by an allergen, and patch testing does not identify a culprit in every patient. Generalized dermatitis, defined as eczematous dermatitis affecting greater than 3 body sites, is often encountered in dermatology practice, especially patch test referral centers. Management for patients with generalized dermatitis who are patch test negative is challenging. The purpose of this article is to outline an approach to this challenging scenario and summarize the paucity of existing literature on patch test negative generalized dermatitis.
Good coupling for the multiscale patch scheme on systems with microscale heterogeneity
NASA Astrophysics Data System (ADS)
Bunder, J. E.; Roberts, A. J.; Kevrekidis, I. G.
2017-05-01
Computational simulation of microscale detailed systems is frequently only feasible over spatial domains much smaller than the macroscale of interest. The 'equation-free' methodology couples many small patches of microscale computations across space to empower efficient computational simulation over macroscale domains of interest. Motivated by molecular or agent simulations, we analyse the performance of various coupling schemes for patches when the microscale is inherently 'rough'. As a canonical problem in this universality class, we systematically analyse the case of heterogeneous diffusion on a lattice. Computer algebra explores how the dynamics of coupled patches predict the large scale emergent macroscale dynamics of the computational scheme. We determine good design for the coupling of patches by comparing the macroscale predictions from patch dynamics with the emergent macroscale on the entire domain, thus minimising the computational error of the multiscale modelling. The minimal error on the macroscale is obtained when the coupling utilises averaging regions which are between a third and a half of the patch. Moreover, when the symmetry of the inter-patch coupling matches that of the underlying microscale structure, patch dynamics predicts the desired macroscale dynamics to any specified order of error. The results confirm that the patch scheme is useful for macroscale computational simulation of a range of systems with microscale heterogeneity.
Intermediate disturbance in experimental landscapes improves persistence of beetle metapopulations.
Govindan, Byju N; Feng, Zhilan; DeWoody, Yssa D; Swihart, Robert K
2015-03-01
Human-dominated landscapes often feature patches that fluctuate in suitability through space and time, but there is little experimental evidence relating the consequences of dynamic patches for species persistence. We used a spatially and temporally dynamic metapopulation model to assess and compare metapopulation capacity and persistence for red flour beetles (Tribolium castaneum) in experimental landscapes differentiated by resource structure, patch dynamics (destruction and restoration), and connectivity. High connectivity increased the colonization rate of beetles, but this effect was less pronounced in heterogeneous relative to homogeneous landscapes. Higher connectivity and faster patch dynamics increased extinction rates in landscapes. Lower connectivity promoted density-dependent emigration. Heterogeneous landscapes containing patches of different carrying capacity enhanced landscape-level occupancy probability. The highest metapopulation capacity and persistence was observed in landscapes with heterogeneous patches, low connectivity, and slow patch dynamics. Control landscapes with no patch dynamics exhibited rapid declines in abundance and approached extinction due to increased adult mortality in the matrix, higher pupal cannibalism by adults, and extremely low rates of exchange between remaining habitable patches. Our results highlight the role of intermediate patch dynamics, intermediate connectivity, and the nature of density dependence of emigration for persistence of species in heterogeneous landscapes. Our results also demonstrate the importance of incorporating local dynamics into the estimation of metapopulation capacity for conservation planning.
Correlation of open cell-attached and excised patch clamp techniques.
Filipovic, D; Hayslett, J P
1995-11-01
The excised patch clamp configuration provides a unique technique for some types of single channel analyses, but maintenance of stable, long-lasting preparations may be confounded by rundown and/or rapid loss of seal. Studies were performed on the amiloride-sensitive Na+ channel, located on the apical surface of A6 cells, to determine whether the nystatin-induced open cell-attached patch could serve as an alternative configuration. Compared to excised inside-out patches, stable preparations were achieved more readily with the open cell-attached patch (9% vs. 56% of attempts). In both preparations, the current voltage (I-V) relation was linear, current amplitudes were equal at opposite equivalent clamped voltages, and Erev was zero in symmetrical Na+ solutions, indicating similar Na+ activities on the cytosolic and external surfaces of the patch. Moreover, there was no evidence that nystatin altered channel activity in the patch because slope conductance (3-4pS) and Erev (75 mV), when the bath was perfused with a high K:low Na solution (ENa = 80 mV), were nearly equal in both patch configurations. Our results therefore indicate that the nystatin-induced open cell-attached patch can serve as an alternative approach to the excised inside-out patch when experiments require modulation of univalent ions in the cytosol.
Single-Layer, All-Metal Patch Antenna Element with Wide Bandwidth
NASA Technical Reports Server (NTRS)
Chamberlain, Neil F.; Hodges, Richard E.; Zawardzki, Mark S.
2012-01-01
It is known that the impedance at the center of a patch antenna element is a short circuit, implying that a wire or post can be connected from the patch to the groundplane at this point without impacting radiation performance. In principle, this central post can be used to support the patch element, thus eliminating the need for dielectric. In spaceborne applications, this approach is problematic because a patch element supported by a single, thin post is highly susceptible to acoustic loads during launch. The technology reported here uses a large-diameter center post as its supporting structure. The supporting structure allows for the fabrication of a sufficiently rigid antenna element that can survive launch loads. The post may be either hollow or solid, depending on fabrication approach and/or mass constraints. The patch antenna element and support post are envisioned as being fabricated (milled) from a single piece of aluminum or other metal. Alternately, the patch plate and support column can be fabricated separately and then joined using fasteners, adhesive, or welding. Casting and electroforming are also viable techniques for manufacturing the metal patch part(s). The patch structure is then either bonded or fastened to the supporting groundplane. Arrays of patch elements can be fabricated by attaching several structures to a common groundplane/support structure.
Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios
NASA Technical Reports Server (NTRS)
Barbosa Kortright, Miguel A.; Waldstein, Seth W.; Simons, Rainee N.
2017-01-01
An almost square patch, a square patch and a stacked square patch with corner truncation for circular polarization (CP) are researched and developed at X-band for cognitive radios. Experimental results indicate, first, that the impedance bandwidth of a CP almost square patch fed from the edge by a 50 ohm line is 1.70% and second, that of a CP square patch fed from the ground plane side by a surface launch connector is 1.87%. Third, the impedance bandwidth of a CP stacked square patch fed by a surface launch connector is 2.22%. The measured center frequency for the CP square patch fed by a surface launch connector without and with an identical stacked patch is 8.45 and 8.1017 GHz, respectively. By stacking a patch, separated by a fixed air gap of 0.254 mm, the center frequency is observed to shift by as much as 348.3 MHz. The shift in center frequency, brought about by the reconfiguring of the physical layer antenna, can be exploited in a cognitive system since it expands the usable frequency spectrum for software reconfiguration in the presence of interference. In addition, varying the fixed air gap in the stacked antenna geometry by increments of 0.254 mm further expands the usable frequency spectrum.
The effects of facilitation and competition on group foraging in patches
Laguë, Marysa; Tania, Nessy; Heath, Joel; Edelstein-Keshet, Leah
2012-01-01
Significant progress has been made towards understanding the social behaviour of animal groups, but the patch model, a foundation of foraging theory, has received little attention in a social context. The effect of competition on the optimal time to leave a foraging patch was considered as early as the original formulation of the marginal value theorem, but surprisingly, the role of facilitation (where foraging in groups decreases the time to find food in patches), has not been incorporated. Here we adapt the classic patch model to consider how the trade-off between facilitation and competition influence optimal group size. Using simple assumptions about the effect of group size on the food-finding time and the sharing of resources, we find conditions for existence of optima in patch residence time and in group size. When patches are close together (low travel times), larger group sizes are optimal. Groups are predicted to exploit patches differently than individual foragers and the degree of patch depletion at departure depends on the details of the trade-off between competition and facilitation. A variety of currencies and group-size effects are also considered and compared. Using our simple formulation, we also study the effects of social foraging on patch exploitation which to date have received little empirical study. PMID:22743132
The effects of facilitation and competition on group foraging in patches.
Laguë, Marysa; Tania, Nessy; Heath, Joel; Edelstein-Keshet, Leah
2012-10-07
Significant progress has been made towards understanding the social behaviour of animal groups, but the patch model, a foundation of foraging theory, has received little attention in a social context. The effect of competition on the optimal time to leave a foraging patch was considered as early as the original formulation of the marginal value theorem, but surprisingly, the role of facilitation (where foraging in groups decreases the time to find food in patches), has not been incorporated. Here we adapt the classic patch model to consider how the trade-off between facilitation and competition influences optimal group size. Using simple assumptions about the effect of group size on the food-finding time and the sharing of resources, we find conditions for existence of optima in patch residence time and in group size. When patches are close together (low travel times), larger group sizes are optimal. Groups are predicted to exploit patches differently than individual foragers and the degree of patch depletion at departure depends on the details of the trade-off between competition and facilitation. A variety of currencies and group-size effects are also considered and compared. Using our simple formulation, we also study the effects of social foraging on patch exploitation which to date have received little empirical study. Copyright © 2012 Elsevier Ltd. All rights reserved.
Loff, Steffan; Wirth, Hartmut; Jester, Iwgo; Hosie, Stuart; Wollmann, Carmen; Schaible, Thomas; Ataman, Ozge; Waag, Karl-Ludwig
2005-11-01
Large defects in patients with congenital diaphragmatic hernia (CDH) are frequently closed with a polytetrafluoroethylene patch (PTFE). Intraoperative problems include lack of abdominal domain for the reduction of organs and closure of the abdominal wall. Main surgical postoperative complication is the recurrence of the hernia. We suggest a new and easy method of patch implantation, improving these problems, and report first follow-up results. In our clinic, 103 children with CDH were treated, and 87 children underwent reconstruction of the diaphragm in the 5 years between 1998 and 2002. In 52 patients, a patch implantation had to be performed. We have been optimizing our complete pediatric and surgical procedure and present a new standardized technique of preparation and implantation of a PTFE patch. The flat patch is folded to a 90 degrees cone. The cone is fixed in its form with few single stitches. It is implanted with an overlapping border of 1 cm circumferentially. The border is separately fixed with absorbable single stitches to keep from rolling up. The rough side of the patch points toward the rim of the diaphragm to enable ingrowth of the connective tissue. In a 1-year follow-up study, the recurrences in the 3 following groups of PTFE patches were studied: conventional implantation (simple patch without overlapping border), patch with separately fixed overlapping border, and cone-shaped patch with overlapping separately fixed border. Thirty-three patients were included in the study. After conventional PTFE-patch implantation, 6 (46%) of 13 patients developed reherniation. After PTFE-patch implantation with separately fixed overlapping border, 1 (11%) of 9 patients had a recurrent hernia. In the group with the PTFE-cone implantation, 1 (9%) of 11 patients developed a recurrence. Meanwhile, another 20 CDH patients received implantation of a cone-shaped patch, and no further recurrence occurred up to now. With the additional space (20 mL) provided by the cone-shaped patch, the closure of the abdomen was easier, and the fundus had intraoperatively a physiological position. This optimized patch implantation technique in large diaphragmatic defects offers considerable advantages especially regarding recurrence of the hernia and closure of the abdomen, which are currently the most challenging surgical problems. 1. The cone-shaped 3-dimensional patch increases abdominal capacity. 2. Redundant chest capacity is reduced, and the reconstructed diaphragm shows a physiological shape. 3. The dome of the patch allows a physiological position of the gastric fundus and a normal Hiss angle, thus preventing gastroesophageal reflux. 4. Additional safety of the implantation is achieved by separate fixation of the overlapping border of the cone, preventing recurrence.
Beitzel, Knut; Chowaniec, David M; McCarthy, Mary Beth; Cote, Mark P; Russell, Ryan P; Obopilwe, Elifho; Imhoff, Andreas B; Arciero, Robert A; Mazzocca, Augustus D
2012-05-01
Rotator cuff reconstructions may be improved by adding growth factors, cells, or other biologic factors into the repair zone. This usually requires a biological carrier (scaffold) to be integrated into the construct and placed in the area of tendon-to-bone healing. This needs to be done without affecting the constructs mechanics. Hypothesis/ The hypothesis was that scaffold placement, as an interposition, has no adverse effects on biomechanical properties of double-row rotator cuff repair. The purpose of this study was to examine the effect of scaffold interposition on the initial strength of rotator cuff repairs. Controlled laboratory study. Twenty-five fresh-frozen shoulders (mean age: 65.5 ± 8.9 years) were randomly assigned to 5 groups. Groups were chosen to represent a broad spectrum of commonly used scaffold types: (1) double-row repair without augmentation, (2) double-row repair with interposition of a fibrin clot (Viscogel), (3) double-row repair with interposition of a collagen scaffold (Mucograft) between tendon and bone, (4) double-row repair with interposition of human dermis patch (ArthroFlex) between tendon and bone, and (5) double-row repair with human dermis patch (ArthroFlex) placed on top of the repair. Cyclic loading to measure displacement was performed to 3000 cycles at 1 Hz with an applied 10- to 100-N load. The ultimate load to failure was determined at a rate of 31 mm/min. There were no significant differences in mean displacement under cyclic loading, slope, or energy absorbed to failure between all groups (P = .128, P = .981, P = .105). Ultimate load to failure of repairs that used the collagen patch as an interposition (573.3 ± 75.6 N) and a dermis patch on top of the reconstruction (575.8 ± 22.6 N) was higher compared with the repair without a scaffold (348.9 ± 98.8 N; P = .018 and P = .025). No significant differences were found for repairs with the fibrin clot as an interposition (426.9 ± 103.6 N) and the decellularized dermis patch as an interposition (469.9 ± 148.6 N; P = .73 and P = .35). Scaffold augmentation did not adversely affect the zero time strength of the tested standard double-row rotator cuff repairs. An increased ultimate load to failure was observed for 2 of the augmentation methods (collagen patch as an interposition and decellularized dermis patch on top of the reconstruction) compared with the nonaugmented repairs. Scaffolds intended for application of growth factors or cellular components in a repair situation did not adversely jeopardize the stability of the operative construct.
Johansen, Cornelia; Mariani, Claire; Mueller, Ralf S
2017-10-01
Adverse food reaction (AFR) is an important differential diagnosis for the pruritic dog. It is usually diagnosed by feeding an elimination diet with a novel protein and carbohydrate source for eight weeks followed by subsequent food provocation. A previous study demonstrated that patch testing dogs with foods had a high sensitivity and negative predictability for selection of elimination diet ingredients. The aim of this study was to investigate patch testing with proteins, carbohydrates and dry commercial dog food in dogs to determine whether there was value in patch testing to aid the diagnosis of canine adverse food reaction. Twenty five privately owned dogs, with confirmed AFR, underwent provocation trials with selected food antigens and patch testing. For proteins, carbohydrates and dry dog food the sensitivity of patch testing was 100%, 70% and 22.2%, respectively; the negative predictive values of patch testing were 100%, 79% and 72%. The positive predictive values of patch testing for proteins and carbohydrates were 75% and 74%, respectively. This study confirmed that patch testing may be useful for the selection of a suitable protein source for an elimination diet in dogs with suspected AFR, but not as a diagnostic tool for canine AFR. Results for proteins are more reliable than for carbohydrates and the majority of positive patch test reactions were observed with raw protein. Patch testing with commercial dog food does not seem to be useful. © 2017 ESVD and ACVD.
Spatial layout affects speed discrimination
NASA Technical Reports Server (NTRS)
Verghese, P.; Stone, L. S.
1997-01-01
We address a surprising result in a previous study of speed discrimination with multiple moving gratings: discrimination thresholds decreased when the number of stimuli was increased, but remained unchanged when the area of a single stimulus was increased [Verghese & Stone (1995). Vision Research, 35, 2811-2823]. In this study, we manipulated the spatial- and phase relationship between multiple grating patches to determine their effect on speed discrimination thresholds. In a fusion experiment, we merged multiple stimulus patches, in stages, into a single patch. Thresholds increased as the patches were brought closer and their phase relationship was adjusted to be consistent with a single patch. Thresholds increased further still as these patches were fused into a single patch. In a fission experiment, we divided a single large patch into multiple patches by superimposing a cross with luminance equal to that of the background. Thresholds decreased as the large patch was divided into quadrants and decreased further as the quadrants were maximally separated. However, when the cross luminance was darker than the background, it was perceived as an occluder and thresholds, on average, were unchanged from that for the single large patch. A control experiment shows that the observed trend in discrimination thresholds is not due to the differences in perceived speed of the stimuli. These results suggest that the parsing of the visual image into entities affects the combination of speed information across space, and that each discrete entity effectively provides a single independent estimate of speed.
Reconfigurable Wideband Circularly Polarized Stacked Square Patch Antenna for Cognitive Radios
NASA Technical Reports Server (NTRS)
Barbosa Kortright, Miguel A.; Waldstein, Seth W.; Simons, Rainee N.
2017-01-01
An almost square patch and a square patch with corner truncation for circularly polarized (CP) and a stacked CP square patch are researched and developed at X-band for cognitive devices. A draft set of presentation charts are attached.
Extending Mondrian Memory Protection
2010-11-01
a kernel semaphore is locked or unlocked. In addition, we extended the system call interface to receive notifications about user-land locking...operations (such as calls to the mutex and semaphore code provided by the C library). By patching the dynamically loadable GLibC5, we are able to test... semaphores , and spinlocks. RTO-MP-IST-091 10- 9 Extending Mondrian Memory Protection to loading extension plugins. This prevents any untrusted code
Honda, Yoshihiro; Suzuki, Shoji; Kaga, Shigeaki; Yoshida, Yukiyo; Kimura, Mitsuhiro; Kamiya, Kentaro; Sakakibara, Kenji; Katsu, Masatake
2015-05-01
The patient was diagnosed with tetralogy of Fallot associated with absent pulmonary valve syndrome and a low birth weight of 1,912 g. He suffered from respiratory distress on day 14 and received non-invasive positive pressure ventilation. At 5 months of age and 4.1 kg, he underwent intracardiac repair including right ventricular outflow repair with a monocusp patch, patch closure of the ventricular septum defect and right pulmonary transposition to the anterior of the ascending aorta following the Lecompte maneuver for airway decompression. He was subsequently discharged to home and exhibited an uneventful clinical course with non-invasive positive pressure ventilation for 5 months postoperatively. However, right pulmonary artery and supra-aortic stenosis was noted 2 years after the operation. Computed tomography (CT) and angiography showed ascending aorta strangulation by the right pulmonary artery with right ventricular outflow regurgitation. Right pulmonary artery reconstruction using polytetrafluoroethylene graft interposition and repeat right ventricular outflow repair with bicuspid hand-sewn valves was therefore performed;the postoperative course was uneventful. Pre- and post-operative management using non-invasive positive pressure ventilation and airway decompression with pulmonary artery translocation is a useful strategy in patients exhibiting symptomatic tetralogy of Fallot associated with absent pulmonary valve syndrome in the neonatal period.
Van Baelen, Dries
2018-01-01
A novel manufacturing procedure for the fabrication of ultra-wideband cavity-backed substrate integrated waveguide antennas on textile substrates is proposed. The antenna cavity is constructed using a single laser-cut electrotextile patch, which is folded around the substrate. Electrotextile slabs protruding from the laser-cut patch are then vertically folded and glued to form the antenna cavity instead of rigid metal tubelets to implement the vertical cavity walls. This approach drastically improves mechanical flexibility, decreases the antenna weight to slightly more than 1 g and significantly reduces alignment errors. As a proof of concept, a cavity-backed substrate integrated waveguide antenna is designed and realized for ultra-wideband operation in the [5.15–5.85] GHz band. Antenna performance is validated in free space as well as in two on body measurement scenarios. Furthermore, the antenna’s figures of merit are characterized when the prototype is bent at different curvature radii, as commonly encountered during deployment on the human body. Also the effect of humidity content on antenna performance is studied. In all scenarios, the realized antenna covers the entire operating frequency band, meanwhile retaining a stable radiation pattern with a broadside gain above 5 dBi, and a radiation efficiency of at least 70%. PMID:29301378
Van Baelen, Dries; Lemey, Sam; Verhaevert, Jo; Rogier, Hendrik
2018-01-03
A novel manufacturing procedure for the fabrication of ultra-wideband cavity-backed substrate integrated waveguide antennas on textile substrates is proposed. The antenna cavity is constructed using a single laser-cut electrotextile patch, which is folded around the substrate. Electrotextile slabs protruding from the laser-cut patch are then vertically folded and glued to form the antenna cavity instead of rigid metal tubelets to implement the vertical cavity walls. This approach drastically improves mechanical flexibility, decreases the antenna weight to slightly more than 1 g and significantly reduces alignment errors. As a proof of concept, a cavity-backed substrate integrated waveguide antenna is designed and realized for ultra-wideband operation in the [5.15-5.85] GHz band. Antenna performance is validated in free space as well as in two on body measurement scenarios. Furthermore, the antenna's figures of merit are characterized when the prototype is bent at different curvature radii, as commonly encountered during deployment on the human body. Also the effect of humidity content on antenna performance is studied. In all scenarios, the realized antenna covers the entire operating frequency band, meanwhile retaining a stable radiation pattern with a broadside gain above 5 dBi, and a radiation efficiency of at least 70%.
An Example-Based Super-Resolution Algorithm for Selfie Images
William, Jino Hans; Venkateswaran, N.; Narayanan, Srinath; Ramachandran, Sandeep
2016-01-01
A selfie is typically a self-portrait captured using the front camera of a smartphone. Most state-of-the-art smartphones are equipped with a high-resolution (HR) rear camera and a low-resolution (LR) front camera. As selfies are captured by front camera with limited pixel resolution, the fine details in it are explicitly missed. This paper aims to improve the resolution of selfies by exploiting the fine details in HR images captured by rear camera using an example-based super-resolution (SR) algorithm. HR images captured by rear camera carry significant fine details and are used as an exemplar to train an optimal matrix-value regression (MVR) operator. The MVR operator serves as an image-pair priori which learns the correspondence between the LR-HR patch-pairs and is effectively used to super-resolve LR selfie images. The proposed MVR algorithm avoids vectorization of image patch-pairs and preserves image-level information during both learning and recovering process. The proposed algorithm is evaluated for its efficiency and effectiveness both qualitatively and quantitatively with other state-of-the-art SR algorithms. The results validate that the proposed algorithm is efficient as it requires less than 3 seconds to super-resolve LR selfie and is effective as it preserves sharp details without introducing any counterfeit fine details. PMID:27064500
The effects of platelet lysate patches on the activity of tendon-derived cells.
Costa-Almeida, Raquel; Franco, Albina R; Pesqueira, Tamagno; Oliveira, Mariana B; Babo, Pedro S; Leonor, Isabel B; Mano, João F; Reis, Rui L; Gomes, Manuela E
2018-03-01
Platelet-derived biomaterials are widely explored as cost-effective sources of therapeutic factors, holding a strong potential for endogenous regenerative medicine. Particularly for tendon repair, treatment approaches that shift the injury environment are explored to accelerate tendon regeneration. Herein, genipin-crosslinked platelet lysate (PL) patches are proposed for the delivery of human-derived therapeutic factors in patch augmentation strategies aiming at tendon repair. Developed PL patches exhibited a controlled release profile of PL proteins, including bFGF and PDGF-BB. Additionally, PL patches exhibited an antibacterial effect by preventing the adhesion, proliferation and biofilm formation by S. aureus, a common pathogen in orthopaedic surgical site infections. Furthermore, these patches supported the activity of human tendon-derived cells (hTDCs). Cells were able to proliferate over time and an up-regulation of tenogenic genes (SCX, COL1A1 and TNC) was observed, suggesting that PL patches may modify the behavior of hTDCs. Accordingly, hTDCs deposited tendon-related extracellular matrix proteins, namely collagen type I and tenascin C. In summary, PL patches can act as a reservoir of biomolecules derived from PL and support the activity of native tendon cells, being proposed as bioinstructive patches for tendon regeneration. Platelet-derived biomaterials hold great interest for the delivery of therapeutic factors for applications in endogenous regenerative medicine. In the particular case of tendon repair, patch augmentation strategies aiming at shifting the injury environment are explored to improve tendon regeneration. In this study, PL patches were developed with remarkable features, including the controlled release of growth factors and antibacterial efficacy. Remarkably, PL patches supported the activity of native tendon cells by up-regulating tenogenic genes and enabling the deposition of ECM proteins. This patch holds great potential towards simultaneously reducing post-implantation surgical site infections and promoting tendon regeneration for prospective in vivo applications. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
"Phase capture" in amblyopia: the influence function for sampled shape.
Levi, Dennis M; Li, Roger W; Klein, Stanley A
2005-06-01
This study was concerned with what stimulus information humans with amblyopia use to judge the shape of simple objects. We used a string of four Gabor patches to define a contour. A fifth, center patch served as the test pattern. The observers' task was to judge the location of the test pattern relative to the contour. The contour was either a straight line, or an arc with positive or negative curvature. We asked whether phase shifts in the inner or outer pairs of patches distributed along the contour influence the perceived shape. That is, we measured the phase shift influence function. Our results, consistent with previous studies, show that amblyopes are imprecise in shape discrimination, showing elevated thresholds for both lines and curves. We found that amblyopes often make much larger perceptual errors (biases) than do normal observers in the absence of phase shifts. These errors tend to be largest for curved shapes and at large separations. In normal observers, shifting the phase of inner patches of the string by 0.25 cycle results in almost complete phase capture (attraction) at the smallest separation (2 lambda), and the capture effect falls off rapidly with separation. A 0.25 cycle shift of the outer pair of patches has a much smaller effect, in the opposite direction (repulsion). While several amblyopic observers showed reduced capture by the phase of the inner patches, to our surprise, several of the amblyopes were sensitive to the phase of the outer patches. We used linear multiple regression to determine the weights of all cues to the task: the carrier phase of the inner patches, carrier phase of the outer patches and the envelope of the outer patches. Compared to normal observers, some amblyopes show a weaker influence of the phase of the inner patches, and a stronger influence of both the phase and envelope of the outer patches. We speculate that this may be a consequence of abnormal "crowding" of the inner patches by the outer ones.
Robust multi-atlas label propagation by deep sparse representation
Zu, Chen; Wang, Zhengxia; Zhang, Daoqiang; Liang, Peipeng; Shi, Yonghong; Shen, Dinggang; Wu, Guorong
2016-01-01
Recently, multi-atlas patch-based label fusion has achieved many successes in medical imaging area. The basic assumption in the current state-of-the-art approaches is that the image patch at the target image point can be represented by a patch dictionary consisting of atlas patches from registered atlas images. Therefore, the label at the target image point can be determined by fusing labels of atlas image patches with similar anatomical structures. However, such assumption on image patch representation does not always hold in label fusion since (1) the image content within the patch may be corrupted due to noise and artifact; and (2) the distribution of morphometric patterns among atlas patches might be unbalanced such that the majority patterns can dominate label fusion result over other minority patterns. The violation of the above basic assumptions could significantly undermine the label fusion accuracy. To overcome these issues, we first consider forming label-specific group for the atlas patches with the same label. Then, we alter the conventional flat and shallow dictionary to a deep multi-layer structure, where the top layer (label-specific dictionaries) consists of groups of representative atlas patches and the subsequent layers (residual dictionaries) hierarchically encode the patchwise residual information in different scales. Thus, the label fusion follows the representation consensus across representative dictionaries. However, the representation of target patch in each group is iteratively optimized by using the representative atlas patches in each label-specific dictionary exclusively to match the principal patterns and also using all residual patterns across groups collaboratively to overcome the issue that some groups might be absent of certain variation patterns presented in the target image patch. Promising segmentation results have been achieved in labeling hippocampus on ADNI dataset, as well as basal ganglia and brainstem structures, compared to other counterpart label fusion methods. PMID:27942077
Kim, Su Jin; Jeon, Hyeshin; Jung, Jae Ho; Lee, Kwang Min; Choi, Hee Young
2018-02-01
To investigate efficacy of over-glasses patching treatment for amblyopic children using visual function improvement and Amblyopia Treatment Index (ATI) changes. In a randomized multi-center controlled clinical trial, 107 children aged 3-7 years with moderate amblyopia (visual acuity in the range of 20/40 to 20/100) were included to receive treatment with either an adhesive skin patch or a fabric over-glasses patch. The patients were prescribed 2 h of patching per day for the sound eye. Best-corrected visual acuity (BCVA) was investigated and ATI questionnaires were collected from parents at 5 weeks and 17 weeks after the initiation of treatment. ATI identifies barriers and problems associated with amblyopia treatment. We compared the changes of visual acuity of amblyopic eyes and ATI scores in two groups. At 17 weeks, the mean visual acuity of the amblyopic eye using Snellen chart improved 3.2 lines in the adhesive patching group and 2.7 lines for an over-glasses patching method that fit over eyeglasses (p = 0.345). A similar proportion of subjects in each group had improvement of ≥ 2 lines (adhesive patching group 67% vs over-glasses patching group 67%, p = 0.372). There was also no difference in treatment burden in each group as measured with the Amblyopia Treatment Index. The only item to demonstrate a significant difference between groups was that related to "Treatment makes the eye or eyelids red" (mean 4.0 ± 1.1 vs 3.0 ± 1.0 at 17 weeks, p = 0.001, for adhesive vs over-glasses patch). Over-glasses patching treatment is a useful option for amblyopia treatment when the patients suffer from adverse effects of using adhesive skin patching.
Robust multi-atlas label propagation by deep sparse representation.
Zu, Chen; Wang, Zhengxia; Zhang, Daoqiang; Liang, Peipeng; Shi, Yonghong; Shen, Dinggang; Wu, Guorong
2017-03-01
Recently, multi-atlas patch-based label fusion has achieved many successes in medical imaging area. The basic assumption in the current state-of-the-art approaches is that the image patch at the target image point can be represented by a patch dictionary consisting of atlas patches from registered atlas images. Therefore, the label at the target image point can be determined by fusing labels of atlas image patches with similar anatomical structures. However, such assumption on image patch representation does not always hold in label fusion since (1) the image content within the patch may be corrupted due to noise and artifact; and (2) the distribution of morphometric patterns among atlas patches might be unbalanced such that the majority patterns can dominate label fusion result over other minority patterns. The violation of the above basic assumptions could significantly undermine the label fusion accuracy. To overcome these issues, we first consider forming label-specific group for the atlas patches with the same label. Then, we alter the conventional flat and shallow dictionary to a deep multi-layer structure, where the top layer ( label-specific dictionaries ) consists of groups of representative atlas patches and the subsequent layers ( residual dictionaries ) hierarchically encode the patchwise residual information in different scales. Thus, the label fusion follows the representation consensus across representative dictionaries. However, the representation of target patch in each group is iteratively optimized by using the representative atlas patches in each label-specific dictionary exclusively to match the principal patterns and also using all residual patterns across groups collaboratively to overcome the issue that some groups might be absent of certain variation patterns presented in the target image patch. Promising segmentation results have been achieved in labeling hippocampus on ADNI dataset, as well as basal ganglia and brainstem structures, compared to other counterpart label fusion methods.
Corridors and some ecological and evolutionary consequences of connectivity.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Orrock, John L
2004-07-01
Abstract - By connecting disjunct patches, corridors may offset the effects of fragmentation by promoting gene flow and population persistence. However, the ultimate effect of corridors on a focal species may hinge upon two considerations: how corridors may affect ecological interactions that impinge upon that species, and how corridors might affect the fixation of novel alleles that ultimately determine fitness and persistence. Using an experimental landscape, I show that corridor-mediated changes in patch shape change seed predation in connected and unconnected patches, and shift the behavior, abundance, and distribution of seed predators. Rodent seed predators removed more seeds in connectedmore » patches, arthropod seed predators removed more seeds in rectangular patches, and avian seed predation did not differ due to patch type. Rodent foraging was greater in the interior of connected patches because changes in patch shape influenced risk perceived by rodents while foraging. Ant communities were also affected by changes in patch shape caused by corridors, rather than corridor effects per se. The distribution and abundance of ants differed among edge-rich areas (corridors and wings), edges, and the patch interior. In rectangular patches, fire ants (Solenopsis spp.) had negative impacts on other ant species. By changing the activity of rodents, and the composition of ant communities, corridors may have important impacts on seeds. Bird-dispersed seeds may benefit from increased dispersal among connected patches, but connected patches also have greater predation risk. Using a simulation model, I demonstrate that gene flow between a stable population and a population that experiences local extinction or a reduction in size (e.g. due to natural or anthropogenic disturbance) can dramatically affect fixation of alleles in the stable population. Alone or in concert, frequent disturbance, high rates of movement, and low habitat quality make it more likely that connectivity-mediated fixation will promote fixation of harmful alleles and reduce fixation of beneficial alleles.« less
Quartararo, N; Barry, P H
1987-12-01
A technical problem associated with the patch clamp technique has been the changing of solutions bathing the membrane patch. The simple technique described here solves this problem by means of a movable polythene sleeve placed on the shaft of the patch clamp pipette. The sleeve is initially placed so that the tip of the pipette is exposed. A gigaohm seal is formed using standard techniques. The patch is then excised and the sleeve is slipped down a few mm past the end of the tip of the pipette. When the pipette and sleeve is now removed from the solution, a small drop of solution covering the membrane patch is held in place at the end of the sleeve by surface tension. The pipette is then easily transferred to a different solution without passing the membrane patch through the air-water interface. The sleeve is then simply pulled back up the pipette shaft to expose the membrane patch to the new solution.
Sarkar, Gunjan; Saha, Nayan Ranjan; Roy, Indranil; Bhattacharyya, Amartya; Bose, Madhura; Mishra, Roshnara; Rana, Dipak; Bhattacharjee, Debashis; Chattopadhyay, Dipankar
2014-05-01
The aim of this work is to examine the effectiveness of mucilage/hydroxypropylmethylcellulose (HPMC) based transdermal patch (matrix type) as a drug delivery device. We have successfully extracted mucilage from Colocasia esculenta (Taro) corms and prepared diltiazem hydrochloride incorporated mucilage/HPMC based transdermal patches using various wt% of mucilage by the solvent evaporation technique. Characterization of both mucilage and transdermal patches has been done by several techniques such as Molisch's test, organoleptic evaluation of mucilage, mechanical, morphological and thermal analysis of transdermal patches. Skin irritation test is studied on hairless Albino rat skin showing that transdermal patches are apparently free of potentially hazardous skin irritation. Fourier transform infrared analysis shows that there is no interaction between drug, mucilage and HPMC while scanning electron microscopy shows the surface morphology of transdermal patches. In vitro drug release time of mucilage-HPMC based transdermal patches is prolonged with increasing mucilage concentration in the formulation. Copyright © 2014 Elsevier B.V. All rights reserved.
Polonchuk, Liudmila
2014-01-01
Patch-clamping is a powerful technique for investigating the ion channel function and regulation. However, its low throughput hampered profiling of large compound series in early drug development. Fortunately, automation has revolutionized the area of experimental electrophysiology over the past decade. Whereas the first automated patch-clamp instruments using the planar patch-clamp technology demonstrated rather a moderate throughput, few second-generation automated platforms recently launched by various companies have significantly increased ability to form a high number of high-resistance seals. Among them is SyncroPatch(®) 96 (Nanion Technologies GmbH, Munich, Germany), a fully automated giga-seal patch-clamp system with the highest throughput on the market. By recording from up to 96 cells simultaneously, the SyncroPatch(®) 96 allows to substantially increase throughput without compromising data quality. This chapter describes features of the innovative automated electrophysiology system and protocols used for a successful transfer of the established hERG assay to this high-throughput automated platform.
An Electronic Patch for wearable health monitoring by reflectance pulse oximetry.
Haahr, Rasmus G; Duun, Sune B; Toft, Mette H; Belhage, Bo; Larsen, Jan; Birkelund, Karen; Thomsen, Erik V
2012-02-01
We report the development of an Electronic Patch for wearable health monitoring. The Electronic Patch is a new health monitoring system incorporating biomedical sensors, microelectronics, radio frequency (RF) communication, and a battery embedded in a 3-dimensional hydrocolloid polymer. In this paper the Electronic Patch is demonstrated with a new optical biomedical sensor for reflectance pulse oximetry so that the Electronic Patch in this case can measure the pulse and the oxygen saturation. The reflectance pulse oximetry solution is based on a recently developed annular backside silicon photodiode to enable low power consumption by the light emitting components. The Electronic Patch has a disposable part of soft adhesive hydrocolloid polymer and a reusable part of hard polylaurinlactam. The disposable part contains the battery. The reusable part contains the reflectance pulse oximetry sensor and microelectronics. The reusable part is 'clicked' into the disposable part when the patch is prepared for use. The patch has a size of 88 mm by 60 mm and a thickness of 5 mm.
Lipid-glass adhesion in giga-sealed patch-clamped membranes.
Opsahl, L R; Webb, W W
1994-01-01
Adhesion between patch-clamped lipid membranes and glass micropipettes is measured by high contrast video imaging of the mechanical response to the application of suction pressure across the patch. The free patch of membrane reversibly alters both its contact angle and radius of curvature on pressure changes. The assumption that an adhesive force between the membrane and the pipette can sustain normal tension up to a maximum Ta at the edge of the free patch accounts for the observed mechanical responses. When the normal component of the pressure-induced membrane tension exceeds Ta membrane at the contact point between the free patch and the lipid-glass interface is pulled away from the pipette wall, resulting in a decreased radius of curvature for the patch and an increased contact angle. Measurements of the membrane radius of curvature as a function of the suction pressure and pipette radius determine line adhesion tensions Ta which range from 0.5 to 4.0 dyn/cm. Similar behavior of patch-clamped cell membranes implies similar adhesion mechanics.
Whyte, Graeme P; McGee, Alan; Jazrawi, Laith; Meislin, Robert
2016-05-01
To evaluate the fixation integrity at time zero of a type I/III collagen patch secured to a chondral defect in the porcine knee using methods typically employed in autologous chondrocyte implantation (ACI) and matrix-assisted chondrocyte implantation. Twenty-four porcine knee specimens underwent a medial parapatellar arthrotomy. A prefabricated template was used to create cartilage defects of 2 cm(2) in the medial femoral condyle. A size-matched collagen patch was fashioned. Four methods of fixation to the chondral defect were analyzed: group 1-saline, group 2-fibrin glue around the periphery of the patch, group 3-fibrin glue applied to the base of the defect and around the periphery of the patch, group 4-6-0 vicryl suture and fibrin glue around the periphery of the patch. Collagen patch fixation was assessed at intervals of 60, 300, 600, 900, and 1,200 cycles from full extension to 90° of flexion, performed manually without application of axial force. Patch fixation was evaluated by 2 independent observers using a customized scoring scale. Mean peripheral detachment of the patch and chondral defect uncovering remained less than 25% for all groups. Area of defect uncovering was significantly increased in group 2 compared with group 4 after 900 and 1,200 cycles (P = .0014 and P = .0025, respectively). Fibrin glue applied to the base of the defect, or suturing of the patch, reduced deformation significantly after 900 cycles. Suture increases the stability of fixation of a type I/III collagen patch to a chondral defect better than fibrin glue alone in the porcine knee after repetitive cycling, with respect to patch detachment and chondral defect uncovering. Application of fibrin glue to the base of the defect, or securing the patch with suture, decreases collagen patch deformation. In cases where minimally invasive techniques do not allow suture fixation of the collagen patch, scaffold fixation may be compromised during articular motion protocols typically used after second- and third-generation ACI procedures. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.
Horne, Jon S; Strickler, Katherine M; Alldredge, Mathew
2011-10-01
A growing number of programs seek to facilitate species conservation using incentive-based mechanisms. Recently, a market-based incentive program for the federally endangered Golden-cheeked Warbler (Dendroica chrysoparia) was implemented on a trial basis at Fort Hood, an Army training post in Texas, USA. Under this program, recovery credits accumulated by Fort Hood through contracts with private landowners are used to offset unintentional loss of breeding habitat of Golden-cheeked Warblers within the installation. Critical to successful implementation of such programs is the ability to value, in terms of changes to overall species viability, both habitat loss and habitat restoration or protection. In this study, we sought to answer two fundamental questions: Given the same amount of change in breeding habitat, does the change in some patches have a greater effect on metapopulation persistence than others? And if so, can characteristics of a patch (e.g., size or spatial location) be used to predict how the metapopulation will respond to these changes? To answer these questions, we describe an approach for using sensitivity analysis of a metapopulation projection model to predict how changes to specific habitat patches would affect species viability. We used a stochastic, discrete-time projection model based on stage-specific estimates of survival and fecundity, as well as various assumptions about dispersal among populations. To assess a particular patch's leverage, we quantified how much metapopulation viability was expected to change in response to changing the size of that patch. We then related original patch size and distance from the largest patch to each patch's leverage to determine if general patch characteristics could be used to develop guidelines for valuing changes to patches within a metapopulation. We found that both the characteristic that best predicted patch leverage and the magnitude of the relationship changed under different model scenarios. Thus, we were unable to find a consistent set of relationships, and therefore we emphasize the dangers in relying on general guidelines to assess patch value. Instead, we provide an approach that can be used to quantitatively evaluate patch value and identify critical needs for future research.
Movement of foraging Tundra Swans explained by spatial pattern in cryptic food densities.
Klaassen, Raymond H G; Nolet, Bart A; Bankert, Daniëlle
2006-09-01
We tested whether Tundra Swans use information on the spatial distribution of cryptic food items (below ground Sago pondweed tubers) to shape their movement paths. In a continuous environment, swans create their own food patches by digging craters, which they exploit in several feeding bouts. Series of short (<1 m) intra-patch movements alternate with longer inter-patch movements (>1 m). Tuber biomass densities showed a positive spatial auto-correlation at a short distance (<3 m), but not at a larger distance (3-8 m). Based on the spatial pattern of the food distribution (which is assumed to be pre-harvest information for the swan) and the energy costs and benefits for different food densities at various distances, we calculated the optimal length of an inter-patch movement. A swan that moves to the patch with the highest gain rate was predicted to move to the adjacent patch (at 1 m) if the food density in the current patch had been high (>25 g/m2) and to a more distant patch (at 7-8 m) if the food density in the current patch had been low (<25 g/m2). This prediction was tested by measuring the response of swans to manipulated tuber densities. In accordance with our predictions, swans moved a long distance (>3 m) from a low-density patch and a short distance (<3 m) from a high-density patch. The quantitative agreement between prediction and observation was greater for swans feeding in pairs than for solitary swans. The result of this movement strategy is that swans visit high-density patches at a higher frequency than on offer and, consequently, achieve a 38% higher long-term gain rate. Swans also take advantage of spatial variance in food abundance by regulating the time in patches, staying longer and consuming more food from rich than from poor patches. We can conclude that the shape of the foraging path is a reflection of the spatial pattern in the distribution of tuber densities and can be understood from an optimal foraging perspective.
Habitat corridors function as both drift fences and movement conduits for dispersing flies.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fried, Joanna H.; Levey Douglas J.; Hogsette, Jerome A.
2005-03-30
Abstract Corridors connect otherwise isolated habitat patches and can direct movement of animals among such patches. In eight experimental landscapes, we tested two hypotheses of how corridors might affect dispersal behavior. The Traditional Corridor hypothesis posits that animals preferentially leave patches via corridors, following them into adjacent patches. The Drift Fence hypothesis posits that animals dispersing through matrix habitat are diverted into patches with corridors because they follow corridors when encountered. House flies (Musca domestica L.), a species that prefers the habitat of our patches and corridors, were released in a central patch (100•100 m) and recaptured in peripheral patchesmore » that were or were not connected by a corridor. Flies were captured more frequently in connected than unconnected patches, thereby supporting the Traditional Corridor hypothesis. The Drift Fence hypothesis was also supported, as flies were captured more frequently in unconnected patches with blind (dead end) corridors than in unconnected patches of equal area without blind corridors. A second experiment tested whether these results might be dependent on the type of patch-matrix boundary encountered by dispersing flies and whether edge-following behavior might be the mechanism underlying the observed corridor effect in the first experiment. We recorded dispersal patterns of flies released along forest edges with dense undergrowth in the forest (‘‘closed’’ edges) and along edges with little forest understory (‘‘open’’ edges). Flies were less likely to cross and more likely to follow closed edges than open edges, indicating that when patch and corridor edges are pronounced, edge-following behavior of flies may direct them along corridors into connected patches. Because edges in the first experiment were open, these results also suggest that corridor effects for flies in that experiment would have been even stronger if the edges around the source patches and corridors had been more closed. Taken together, our results suggest that corridors can affect dispersal of organisms in unappreciated ways (i.e., as drift fences) and that edge type can alter dispersal behavior.« less
Reducible dictionaries for single image super-resolution based on patch matching and mean shifting
NASA Astrophysics Data System (ADS)
Rasti, Pejman; Nasrollahi, Kamal; Orlova, Olga; Tamberg, Gert; Moeslund, Thomas B.; Anbarjafari, Gholamreza
2017-03-01
A single-image super-resolution (SR) method is proposed. The proposed method uses a generated dictionary from pairs of high resolution (HR) images and their corresponding low resolution (LR) representations. First, HR images and the corresponding LR ones are divided into patches of HR and LR, respectively, and then they are collected into separate dictionaries. Afterward, when performing SR, the distance between every patch of the input LR image and those of available LR patches in the LR dictionary is calculated. The minimum distance between the input LR patch and those in the LR dictionary is taken, and its counterpart from the HR dictionary is passed through an illumination enhancement process. By this technique, the noticeable change of illumination between neighbor patches in the super-resolved image is significantly reduced. The enhanced HR patch represents the HR patch of the super-resolved image. Finally, to remove the blocking effect caused by merging the patches, an average of the obtained HR image and the interpolated image obtained using bicubic interpolation is calculated. The quantitative and qualitative analyses show the superiority of the proposed technique over the conventional and state-of-art methods.
Pathogen transmission at stage-structured infectious patches: Killers and vaccinators.
Caraco, Thomas; Turner, Wendy C
2018-01-07
Spatial localization of an obligate-killing, free-living pathogen generates a landscape of patches where new infections occur. As an infectious patch ages, both pathogen exposure at the patch and the probability of lethal infection following exposure can decline. We model stage-structured infectious patches, where non-lethal exposure can naturally "vaccinate" susceptible hosts. We let the between-stage difference in pathogen transmission, and then the between-stage difference in patch virulence, increase independently of other parameters. Effects of increasing either between-stage difference (about a fixed mean) depend on the probability a patch transitions from the first to second stage, i.e., the chance that a killer patch becomes a vaccinator. For slower stage transition, greater between-stage differences decreased susceptibles, and increased both resistant-host and killer patch numbers. But our examples reveal that each effect can be reversed when between-stage transition occurs more rapidly. For sufficiently rapid stage transition, increased between-stage virulence differences can lead to pathogen extinction, and leave the host at disease-free equilibrium. The model's general significance lies in demonstrating how epidemiological variation among sites of environmentally transmitted disease can strongly govern host-parasite dynamics. Copyright © 2017 Elsevier Ltd. All rights reserved.
Giga-seal formation alters properties of sodium channels of human myoballs.
Fahlke, C; Rüdel, R
1992-03-01
The influence of giga-seal formation on the properties of the Na+ channels within the covered membrane patch was investigated with a whole-cell pipette and a patch pipette applied to the same cell. Current kinetics, current/voltage relation and channel densities were determined in three combinations: (i) voltage-clamping and current recording with the whole-cell pipette, (ii) voltage-clamping with the whole-cell pipette and current recording with the patch pipette and, (iii) voltage-clamping and current recording with the patch pipette. The Hodgkin-Huxley (1952) parameters tau m and tau h were smaller for the patch currents than for the whole cell, and the h infinity curve was shifted in the negative direction. The channel density was of the order of 10 times smaller. All effects were independent of the extracellular Ca2+ concentration. The capacitive current generated in the patch by the whole-cell Na+ current and its effect on the transmembrane voltage of the patch were evaluated. The kinetic parameters of the Na+ channels in the patch did not depend on whether the voltage was clamped with the whole-cell pipette or the patch pipette. Thus, the results are not due to spurious voltage.
Magrach, Ainhoa; Larrinaga, Asier R; Santamaría, Luis
2012-01-01
Habitat fragmentation has become one of the major threats to biodiversity worldwide, particularly in the case of forests, which have suffered enormous losses during the past decades. We analyzed how changes in patch configuration and habitat quality derived from the fragmentation of austral temperate rainforests affect the distribution of six species of forest-dwelling climbing and epiphytic angiosperms. Epiphyte and vine abundance is primarily affected by the internal characteristics of patches (such as tree size, the presence of logging gaps or the proximity to patch edges) rather than patch and landscape features (such as patch size, shape or connectivity). These responses were intimately related to species-specific characteristics such as drought- or shade-tolerance. Our study therefore suggests that plant responses to fragmentation are contingent on both the species' ecology and the specific pathways through which the study area is being fragmented, (i.e. extensive logging that shaped the boundaries of current forest patches plus recent, unregulated logging that creates gaps within patches). Management practices in fragmented landscapes should therefore consider habitat quality within patches together with other spatial attributes at landscape or patch scales.
Habitat patch size and nesting success of yellow-breasted chats
Dick E. Burhans; Frank R. Thompson III
1999-01-01
We measured vegetation at shrub patches used for nesting by Yellow-breasted Chats (Icteria virens) to evaluate the importance of nesting habitat patch features on nest predation, cowbird parasitism, and nest site selection. Logistic regression models indicated that nests in small patches (average diameter
Kamenskiy, Alexey V.; Pipinos, Iraklis I.; MacTaggart, Jason N.; Jaffar Kazmi, Syed A.; Dzenis, Yuris A.
2011-01-01
Patch angioplasty is the most common technique used for the performance of carotid endarterectomy. A large number of patching materials are available for use while new materials are being continuously developed. Surprisingly little is known about the mechanical properties of these materials and how these properties compare with those of the carotid artery wall. Mismatch of the mechanical properties can produce mechanical and hemodynamic effects that may compromise the long-term patency of the endarterectomized arterial segment. The aim of this paper was to systematically evaluate and compare the biaxial mechanical behavior of the most commonly used patching materials. We compared PTFE (n = 1), Dacron (n = 2), bovine pericardium (n = 10), autogenous greater saphenous vein (n = 10), and autogenous external jugular vein (n = 9) with the wall of the common carotid artery (n = 18). All patching materials were found to be significantly stiffer than the carotid wall in both the longitudinal and circumferential directions. Synthetic patches demonstrated the most mismatch in stiffness values and vein patches the least mismatch in stiffness values compared to those of the native carotid artery. All biological materials, including the carotid artery, demonstrated substantial nonlinearity, anisotropy, and variability; however, the behavior of biological and biologically-derived patches was both qualitatively and quantitatively different from the behavior of the carotid wall. The majority of carotid arteries tested were stiffer in the circumferential direction, while the opposite anisotropy was observed for all types of vein patches and bovine pericardium. The rates of increase in the nonlinear stiffness over the physiological stress range were also different for the carotid and patching materials. Several carotid wall samples exhibited reverse anisotropy compared to the average behavior of the carotid tissue. A similar characteristic was observed for two of 19 vein patches. The obtained results quantify, for the first time, significant mechanical dissimilarity of the currently available patching materials and the carotid artery. The results can be used as guidance for designing more efficient patches with mechanical properties resembling those of the carotid wall. The presented systematic comparative mechanical analysis of the existing patching materials provides valuable information for patch selection in the daily practice of carotid surgery and can be used in future clinical studies comparing the efficacy of different patches in the performance of carotid endarterectomy. PMID:22168740
Elshoff, Jan-Peer; Braun, Marina; Andreas, Jens-Otto; Middle, Michelle; Cawello, Willi
2012-04-01
The dopamine agonist rotigotine is formulated in a transdermal delivery system (patch) for once-daily application. It has been reported as efficacious in the treatment of idiopathic Parkinson's disease (PD) and restless legs syndrome. This article summarizes the results of 3 clinical studies conducted to characterize the 24-hour pharmacokinetic profile of rotigotine in steady state and the effect of different patch application sites on this profile. In addition, the relative bioavailability of a single, large patch versus 2 smaller patches was assessed. One Phase I study (SP871) assessed the steady-state pharmacokinetic properties at different application sites at a rotigotine maintenance dose of 3 mg/24 hours in healthy participants. Due to tolerability issues, the steady-state pharmacokinetic properties of rotigotine at higher doses (8 mg/24 hours) was assessed in 2 Phase I studies (SP630, SP651) in early-stage PD patients. Relative rotigotine bioavailability from a 40 cm(2) patch versus 2 × 20 cm(2) patches (SP651) and from a 15 cm(2) patch versus 1 × 5 cm(2) + 1 × 10 cm(2) patches (SP871) was also evaluated. Rotigotine concentrations in plasma were analyzed using a validated LC-MS/MS method. The pharmacokinetic variables were calculated using standard noncompartmental analysis. Release of rotigotine to the skin was 31% to 62% of total drug content in the patch. Variability of rotigotine exposure was low within participants (15%) compared with the variability observed between participants (54%). Rotigotine exposure increased proportionally in the therapeutic dose range of 2 mg/24 hours to 8 mg/24 hours. Plasma concentrations at steady state were stable over the 24-hour patch-on period. Delivery via a single, large patch compared with a combination of smaller patches did not appear to influence exposure to rotigotine. Bioavailability showed some variability depending on patch application site (hip, shoulder, abdomen, flank, thigh, upper arm); the respective mean ratios for AUC ranged between 0.87 (abdomen vs flank) and 1.46 (shoulder vs thigh). Continuous rotigotine delivery via a once-daily transdermal patch generated stable mean steady-state 24-hour plasma concentrations in healthy participants as well as patients with early-stage PD. Doses were achieved either by application of 1 large patch or a combination of smaller patches, resulting in the same total surface area. Copyright © 2012 Elsevier HS Journals, Inc. All rights reserved.
A clinical study of transdermal contraceptive patch in Thai adolescence women.
Piyasirisilp, Rachatapon; Taneepanichskul, Surasak
2008-02-01
To study cycle control, compliance and safety of a transdermal contraceptive patch in adolescent Thai women. Fifty-eight healthy women were assigned to receive 3 cycles of contraceptive patch (ethinyl estradiol 20 microg and norelgestromin 150 microg/day). All participants aged 16-20 years were invited to participate from the family planning clinic at King Chulalongkorn Memorial Hospital. Data were collected on adverse effects, perceived advantages and disadvantages, body weight, blood pressure, patch detachments and compliance. Data were analyzed using mean, percentage and student's t-test. The participants' average age was 19.4 years, height 158.8 cm, weight 51.8 kg, BMI 20.8 Kg/m2. The most location of patch application was the abdomen and the most adverse event was breast tenderness (31.0%) followed by application site reaction, nausea vomiting and headache respectively. The breast symptom was mild in severity. The participants reported decrease in dysmenorrhea and shorter duration of bleeding. There were no significant changes in body weight and blood pressure. The improvement of their facial acne was reported. There were no pregnancies during use and the adhesion of the contraceptive patch is excellent. Partial patch detachment was reported in only 6.9%. No completed patch detachment was found. The present study found an overall positive impression of a new transdermal contraceptive patch. The good compliance and few side effects were demonstrated. The adhesive patch contraceptive was excellent.
Assessment of optimal strategies in a two-patch dengue transmission model with seasonality.
Kim, Jung Eun; Lee, Hyojung; Lee, Chang Hyeong; Lee, Sunmi
2017-01-01
Emerging and re-emerging dengue fever has posed serious problems to public health officials in many tropical and subtropical countries. Continuous traveling in seasonally varying areas makes it more difficult to control the spread of dengue fever. In this work, we consider a two-patch dengue model that can capture the movement of host individuals between and within patches using a residence-time matrix. A previous two-patch dengue model without seasonality is extended by adding host demographics and seasonal forcing in the transmission rates. We investigate the effects of human movement and seasonality on the two-patch dengue transmission dynamics. Motivated by the recent Peruvian dengue data in jungle/rural areas and coast/urban areas, our model mimics the seasonal patterns of dengue outbreaks in two patches. The roles of seasonality and residence-time configurations are highlighted in terms of the seasonal reproduction number and cumulative incidence. Moreover, optimal control theory is employed to identify and evaluate patch-specific control measures aimed at reducing dengue prevalence in the presence of seasonality. Our findings demonstrate that optimal patch-specific control strategies are sensitive to seasonality and residence-time scenarios. Targeting only the jungle (or endemic) is as effective as controlling both patches under weak coupling or symmetric mobility. However, focusing on intervention for the city (or high density areas) turns out to be optimal when two patches are strongly coupled with asymmetric mobility.
Sheng, Sheng; Ling, Meng; Fu-an, Wu; Baoping, Li
2015-01-01
Foraging parasitoids often must estimate local risk of predation just as they must estimate local patch value. Here, we investigate the effects a generalist predator Chlaenius bioculatus (Coleoptera: Carabidae), has on the oviposition behavior and the patch residence decisions of a solitary parasitoid Meteorus pulchricornis (Hymenoptera: Braconidae) in response to the varying host quality of Spodoptera litura (Lepidoptera: Noctuidae) larvae (L2 and L4). M. pulchricornis attacked more L4 than on L2 hosts, with the difference in attack rate varying depending on predation treatments, greater in the presence (either actively feeding or not) of the predator than in the absence of it. The parasitoid attacked fewer L2 and L4 hosts when the predator was actively feeding than when it was not feeding or not present in the patch. M. pulchricornis decreased the patch leaving tendency with increasing rejections of hosts, but increased the tendency in response to the presence of the predator as compared with the absence of it, and furthermore, increased the patch leaving tendency when the predator was actively feeding as compared with when it was not. Our study suggests that M. pulchricornis can exploit high quality patches while minimizing predation risk, by attacking more hosts in high quality patches while reducing total patch time in response to risk of predation. PMID:25943317
NASA Technical Reports Server (NTRS)
Smith, Andrew M.; Davis, Robert Ben; LaVerde, Bruce T.; Jones, Douglas C.; Band, Jonathon L.
2012-01-01
Using the patch method to represent the continuous spatial correlation function of a phased pressure field over a structural surface is an approximation. The approximation approaches the continuous function as patches become smaller. Plotting comparisons of the approximation vs the continuous function may provide insight revealing: (1) For what patch size/density should the approximation be very good? (2) What the approximation looks like when it begins to break down? (3) What the approximation looks like when the patch size is grossly too large. Following these observations with a convergence study using one FEM may allow us to see the importance of patch density. We may develop insights that help us to predict sufficient patch density to provide adequate convergence for the intended purpose frequency range of interest
NASA Astrophysics Data System (ADS)
Wang, YUAN; Hejuan, LIANG; Ping, HUANG; Xiaoqiang, AN; Jian, JIANG; Lili, CUI
2018-05-01
In the present study, the electret 5-fluorouracil patch was developed, the effective surface potential, piezoelectric coefficient d 33, open-circuit thermally stimulated discharge (TSD) current spectra and shear adhesion of the patch were measured. The drug release profile of the patch was determined by using high performance liquid chromatography method. A stable potential difference which was positively dependent on the surface potential of the electret was generated on two sides of the patch. The measurements of d 33 coefficient, TSD current spectra and adhesion performance showed that the electrostatic field of the electret could cause polarization and cohesive strength decreasing of the matrix molecules, change the distribution and interaction of the drug molecules in patch, therefore to increase the release of drug from the transdermal patch.
Kotliar, Natasha B.; Wiens, John A.
1990-01-01
We develop a hierarchical model of heterogeneity that provides a framework for classifying patch structure across a range of scales. Patches at lower levels in the hierarchy are more simplistic and correspond to the traditional view of patches. At levels approaching the upper bounds of the hierarchy the internal structure becomes more heterogeneous and boundaries more ambiguous. At each level in the hierarchy, patch structure will be influenced by both contrast among patches as well as the degree of aggregation of patches at lower levels in the hierarchy. We apply this model to foraging theory, but it has wider applications as in the study of habitat selection, population dynamics, and habitat fragmentation. It may also be useful in expanding the realm of landscape ecology beyond the current focus on anthropocentric scales.
Koppes, S A; Ljubojevic Hadzavdic, S; Jakasa, I; Franceschi, N; Jurakić Tončić, R; Marinović, B; Brans, R; Gibbs, S; Frings-Dresen, M H W; Rustemeyer, T; Kezic, S
2017-06-01
Recent studies have demonstrated allergen-specific differences in the gene expression of inflammatory mediators in patch tested skin. To determine levels of various inflammatory mediators in the stratum corneum (SC) after patch testing with common contact allergens and the skin irritant sodium lauryl sulfate (SLS). In total, 27 individuals who had previously patch tested positive to nickel, chromium, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) or para-phenylenediamine were retested and then patch tested with SLS and petrolatum, with petrolatum serving as the patch test control. At 72 h, the test sites were clinically graded and the SC samples collected on adhesive tape. The levels of 18 of the 32 quantified mediators differed significantly from that of the control patches for at least one of the tested substances. SLS and MCI/MI induced the largest number of immunomediators. Interleukin (IL)-16 levels were significantly higher in patch test reactions in all allergens than they were in the controls, while no significant difference was detected for SLS. Furthermore, a strong negative correlation was found between strength of patch test reaction and IL-1α levels. Cytokine profiles in the SC of patch tested skin did not show a distinct allergen-specific pattern. However, MCI/MI induced a larger and wider immune response than the other allergens, perhaps due to its potency as an irritant. The levels of IL-16 were significantly increased in patch test reactions to allergens but not to SLS; thus, they may help clinicians to differentiate between allergic contact dermatitis and irritant contact dermatitis. © 2016 British Association of Dermatologists.
Grassland bird use of oak barrens and dry prairies in Wisconsin
Vos, Susan M.; Ribic, Christine A.
2011-01-01
Grassland bird populations have declined more than any other group of birds in North America and are of conservation concern to state and federal agencies. We determined relative abundances of grassland birds in oak barrens and dry sand prairies—native habitat types rare in the state of Wisconsin. We also investigated the association of relative abundance, patch size, and patch vegetation. Our study was conducted May–July 2000–2002 on Fort McCoy Military Installation in Monroe County, Wisconsin. Fourteen grassland bird species were found in native habitat patches. Vesper sparrow (Pooecetes gramineus), grasshopper sparrow (Ammodramus savannarum), and field sparrow (Spizella pusilla) were the most abundant grassland bird species; all are species of management concern in Wisconsin. Of the most abundant species, only grasshopper sparrow relative abundance increased as patch size increased; vesper sparrow and field sparrow relative abundances decreased as patch size increased. Though found at lower relative abundances, horned larks (Erephila alpestris), savannah sparrows (Passerculus sandwichensis), and upland sandpipers (Bartramia longicauda) were found at higher relative abundances as patch size increased. Patch vegetation was important for some species. Vesper sparrows were found at higher abundances in patches with shorter, less dense vegetation and higher woody cover, eastern meadowlark (Sturnella magna) relative abundances were higher in patches with higher proportions of grass, and dickcissel (Spiza americana) relative abundances were higher in patches with taller, denser vegetation and lower proportions of litter. Native habitats are important for grassland bird species of management concern and large patches are particularly important for some of them.
[Analysis of urban forest landscape pattern in Hefei].
Wu, Zemin; Wu, Wenyou; Gao, Jian; Zhang, Shaojie
2003-12-01
Based on the theory and methodology of landscape ecology, the landscape pattern of the study area (17.6 km2) in the downtown of Hefei was analyzed by using the techniques of RS, GPS and GIS. The object was to provide a comprehensive method to study urban forest structure and its function in environmental improvement. The results showed that there were 5 major landscape elements, i.e., building and hard pavement surface, water, road, urban forest, and general green land in the area. The landscape matrix was building and pavement surface, occupied 73.13% of total land. Road was the typical corridor element in the city and occupied 6.89%. Green land occupied 11.44%, in which, urban forest patch occupied 9.18%. There were 408 urban forest patches, with an area of 161.16 hm2. The average area of the patch was 0.396 hm2, and the maximum area was 12 hm2. 48% of urban forest patch was identified as small scale patches with < 500 m2 of area, and only 8.6% of them was larger than 1 hm2. The number of general green land patch was 255, with an area of 39.74 hm2, which accounted for 2.26% of land area, and its average and maximum area was 0.1558 hm2 and 3.86 hm2, respectively. There were 147 water patches, with an area of 149.93 hm2, and occupied 8.54% of land, and the average and maximum area of the patch was 1.02 hm2 and 16 hm2, respectively. In the study area, both of the Shannon-Weiner landscape diversity index and evenness were low, only 0.928 and 0.576, respectively. In addition, the dominance of urban forest patch and general green land was 0.39 showing that the two landscape elements had a certain influence on the environment of the study area. The concept of interior habitat for forest was introduced in this paper, which was employed to make a scale class system of urban forest patch. The threshold area with interior habitat for urban forest patch was 9800 m2, and there was 31.69 hm2 of interior habitat of urban forest in total, which occupied 19.7% of the total area of urban forest patch. This situation was not favorable for providing more habitats to support species diversity. It's suggested that the concept of interior habitat could be employed to identify urban forest patch, and a scale system of small scale patch of urban forest-middle patch-large patch-extra large patch was build in the paper. Based on this system, the ratio of different scales of urban forest patch in the study area should be 2:2:2:3. The authors also suggested that larger pieces (1.5-3.0 hm2) of urban forest patch should be built, and more urban forests should be established in the northeastern part of the city in the future.
Expedient Repair Materials for Roadway Pavements
2005-03-01
SILSPEC 900 PNS Patch/spall SSI Const. & Indus. Elastomeric conc. Matls Sikadur 22 Lo-Mod Sika Corp. Epoxy polymer concrete SikaTop 123 Plus Thin...patch Sika 2-component, polymer- 15 min modified Sikaset Roadway Patch Patch/spall Sika 1-comp. with high 15-25 min (15 min) (2000) alumina cement (not
DOT National Transportation Integrated Search
2017-06-01
The long-term performance of pothole patches largely depends on the selection of the patching method. A number of pothole patching methods are in practice in Minnesota and other nearby states. However, pavement maintenance crews often encounter probl...
Soutullo, Alvaro; Limiñana, Rubén; Urios, Vicente; Surroca, Martín; A Gill, Jennifer
2006-09-01
Expanding populations offer an opportunity to uncover the processes driving spatial variation in distribution and abundance. Individual settlement decisions will be influenced by the availability and relative quality of patches, and by how these respond to changes in conspecific density. For example, conspecific presence can alter patch suitability through reductions in resource availability or territorial exclusion, leading to buffer effect patterns of disproportionate population expansion into poorer quality areas. However, conspecific presence can also enhance patch suitability through Allee effect processes, such as transmission of information about resources or improved predator detection and deterrence. Here, we explore the factors underlying the settlement pattern of a growing population of Montagu's harriers (Circus pygargus) in Spain. The population increased exponentially between 1981 and 2001, but stabilised between 2001 and 2004. This population increase occurred alongside a remarkable spatial expansion, with novel site use occurring prior to maximum densities in occupied sites being reached. However, no temporal trends in fecundity were observed and, within sites, average fecundity did not decline with increasing density. Across the population, variance in productivity did increase with population size, suggesting a complex pattern of density-dependent costs and benefits. We suggest that both Allee and buffer effects are operating in this system, with the benefits of conspecific presence counteracting density-dependent declines in resource availability or quality.
Measuring glomerular number from kidney MRI images
NASA Astrophysics Data System (ADS)
Thiagarajan, Jayaraman J.; Natesan Ramamurthy, Karthikeyan; Kanberoglu, Berkay; Frakes, David; Bennett, Kevin; Spanias, Andreas
2016-03-01
Measuring the glomerular number in the entire, intact kidney using non-destructive techniques is of immense importance in studying several renal and systemic diseases. Commonly used approaches either require destruction of the entire kidney or perform extrapolation from measurements obtained from a few isolated sections. A recent magnetic resonance imaging (MRI) method, based on the injection of a contrast agent (cationic ferritin), has been used to effectively identify glomerular regions in the kidney. In this work, we propose a robust, accurate, and low-complexity method for estimating the number of glomeruli from such kidney MRI images. The proposed technique has a training phase and a low-complexity testing phase. In the training phase, organ segmentation is performed on a few expert-marked training images, and glomerular and non-glomerular image patches are extracted. Using non-local sparse coding to compute similarity and dissimilarity graphs between the patches, the subspace in which the glomerular regions can be discriminated from the rest are estimated. For novel test images, the image patches extracted after pre-processing are embedded using the discriminative subspace projections. The testing phase is of low computational complexity since it involves only matrix multiplications, clustering, and simple morphological operations. Preliminary results with MRI data obtained from five kidneys of rats show that the proposed non-invasive, low-complexity approach performs comparably to conventional approaches such as acid maceration and stereology.
Automated age-related macular degeneration classification in OCT using unsupervised feature learning
NASA Astrophysics Data System (ADS)
Venhuizen, Freerk G.; van Ginneken, Bram; Bloemen, Bart; van Grinsven, Mark J. J. P.; Philipsen, Rick; Hoyng, Carel; Theelen, Thomas; Sánchez, Clara I.
2015-03-01
Age-related Macular Degeneration (AMD) is a common eye disorder with high prevalence in elderly people. The disease mainly affects the central part of the retina, and could ultimately lead to permanent vision loss. Optical Coherence Tomography (OCT) is becoming the standard imaging modality in diagnosis of AMD and the assessment of its progression. However, the evaluation of the obtained volumetric scan is time consuming, expensive and the signs of early AMD are easy to miss. In this paper we propose a classification method to automatically distinguish AMD patients from healthy subjects with high accuracy. The method is based on an unsupervised feature learning approach, and processes the complete image without the need for an accurate pre-segmentation of the retina. The method can be divided in two steps: an unsupervised clustering stage that extracts a set of small descriptive image patches from the training data, and a supervised training stage that uses these patches to create a patch occurrence histogram for every image on which a random forest classifier is trained. Experiments using 384 volume scans show that the proposed method is capable of identifying AMD patients with high accuracy, obtaining an area under the Receiver Operating Curve of 0:984. Our method allows for a quick and reliable assessment of the presence of AMD pathology in OCT volume scans without the need for accurate layer segmentation algorithms.
NASA Astrophysics Data System (ADS)
Hong, Yang
Precipitation estimation from satellite information (VISIBLE , IR, or microwave) is becoming increasingly imperative because of its high spatial/temporal resolution and board coverage unparalleled by ground-based data. After decades' efforts of rainfall estimation using IR imagery as basis, it has been explored and concluded that the limitations/uncertainty of the existing techniques are: (1) pixel-based local-scale feature extraction; (2) IR temperature threshold to define rain/no-rain clouds; (3) indirect relationship between rain rate and cloud-top temperature; (4) lumped techniques to model high variability of cloud-precipitation processes; (5) coarse scales of rainfall products. As continuing studies, a new version of Precipitation Estimation from Remotely Sensed Information using Artificial Neural Network (PERSIANN), called Cloud Classification System (CCS), has been developed to cope with these limitations in this dissertation. CCS includes three consecutive components: (1) a hybrid segmentation algorithm, namely Hierarchically Topographical Thresholding and Stepwise Seeded Region Growing (HTH-SSRG), to segment satellite IR images into separated cloud patches; (2) a 3D feature extraction procedure to retrieve both pixel-based local-scale and patch-based large-scale features of cloud patch at various heights; (3) an ANN model, Self-Organizing Nonlinear Output (SONO) network, to classify cloud patches into similarity-based clusters, using Self-Organizing Feature Map (SOFM), and then calibrate hundreds of multi-parameter nonlinear functions to identify the relationship between every cloud types and their underneath precipitation characteristics using Probability Matching Method and Multi-Start Downhill Simplex optimization techniques. The model was calibrated over the Southwest of United States (100°--130°W and 25°--45°N) first and then adaptively adjusted to the study region of North America Monsoon Experiment (65°--135°W and 10°--50°N) using observations from Geostationary Operational Environmental Satellite (GOES) IR imagery, Next Generation Radar (NEXRAD) rainfall network, and Tropical Rainfall Measurement Mission (TRMM) microwave rain rate estimates. CCS functions as a distributed model that first identifies cloud patches and then dispatches different but the best matching cloud-precipitation function for each cloud patch to estimate instantaneous rain rate at high spatial resolution (4km) and full temporal resolution of GOES IR images (every 30-minute). Evaluated over a range of spatial and temporal scales, the performance of CCS compared favorably with GOES Precipitation Index (GPI), Universal Adjusted GPI (UAGPI), PERSIANN, and Auto-Estimator (AE) algorithms, consistently. Particularly, the large number of nonlinear functions and optimum IR-rain rate thresholds of CCS model are highly variable, reflecting the complexity of dominant cloud-precipitation processes from cloud patch to cloud patch over various regions. As a result, CCS can more successfully capture variability in rain rate at small scales than existing algorithms and potentially provides rainfall product from GOES IR-NEXARD-TRMM TMI (SSM/I) at 0.12° x 0.12° and 3-hour resolution with relative low standard error (˜=3.0mm/hr) and high correlation coefficient (˜=0.65).
Seid, Robert C; Reinisch, Christoph; Schlegl, Robert; Moehlen, Michael; Meinke, Andreas; Lundberg, Urban
2014-02-01
Dry tetanus toxoid (TTx) patches were formulated without any adjuvant, with excipients to impart antigen stabilization and to enhance skin delivery. The booster effects of the TTx patches were assessed using a guinea pig model. The study revealed significant rises in TTx IgG titers induced by the TTx patches after a low-dose subcutaneous (s.c.) prime with TTx adsorbed to aluminum hydroxide. The TTx patch can therefore be considered an effective alternative to a subcutaneous booster.
The Defender’s Dilemma: Charting a Course Toward Cybersecurity
2015-01-01
Security concerns on the Internet began with the introduction of the Morris worm in November 1988,1 and since that time we have wit- nessed the...Patch Tuesday .” This is when security patches and updates are released for users to implement. As such, “Exploit Wednesday” usually fol- lows “Patch... Tuesday ,” as users are not generally quick to immediately patch their systems. 23 E.g., Oracle or Microsoft patch on a fixed schedule, but will make
Skin patch and vaginal ring versus combined oral contraceptives for contraception.
Lopez, Laureen M; Grimes, David A; Gallo, Maria F; Stockton, Laurie L; Schulz, Kenneth F
2013-04-30
The delivery of combination contraceptive steroids from a transdermal contraceptive patch or a contraceptive vaginal ring offers potential advantages over the traditional oral route. The transdermal patch and vaginal ring could require a lower dose due to increased bioavailability and improved user compliance. To compare the contraceptive effectiveness, cycle control, compliance (adherence), and safety of the contraceptive patch or the vaginal ring versus combination oral contraceptives (COCs). Through February 2013, we searched MEDLINE, POPLINE, CENTRAL, LILACS, ClinicalTrials.gov, and ICTRP for trials of the contraceptive patch or the vaginal ring. Earlier searches also included EMBASE. For the initial review, we contacted known researchers and manufacturers to identify other trials. We considered randomized controlled trials comparing a transdermal contraceptive patch or a contraceptive vaginal ring with a COC. Data were abstracted by two authors and entered into RevMan. For dichotomous variables, the Peto odds ratio (OR) with 95% confidence intervals (CI) was calculated. For continuous variables, the mean difference was computed. We also assessed the quality of evidence for this review. We found 18 trials that met our inclusion criteria. Of six patch studies, five examined the marketed patch containing norelgestromin plus ethinyl estradiol (EE); one studied a patch in development that contains levonorgestrel (LNG) plus EE. Of 12 vaginal ring trials, 11 examined the same marketing ring containing etonogestrel plus EE; one studied a ring being developed that contains nesterone plus EE.Contraceptive effectiveness was not significantly different for the patch or ring versus the comparison COC. Compliance data were limited. Patch users showed better compliance than COC users in three trials. For the norelgestromin plus EE patch, ORs were 2.05 (95% CI 1.83 to 2.29) and 2.76 (95% CI 2.35 to 3.24). In the levonorgestrel plus EE patch report, patch users were less likely to have missed days of therapy (OR 0.36; 95% CI 0.25 to 0.51). Of four vaginal ring trials, one found ring users had more noncompliance (OR 3.99; 95% CI 1.87 to 8.52), while another showed more compliance with the regimen (OR 1.67; 95% CI 1.04 to 2.68).More patch users discontinued early than COC users. ORs from two meta-analyses were 1.59 (95% CI 1.26 to 2.00) and 1.56 (95% CI 1.18 to 2.06) and another trial showed OR 2.57 (95% CI 0.99 to 6.64). Patch users also had more discontinuation due to adverse events than COC users. Users of the norelgestromin-containing patch reported more breast discomfort, dysmenorrhea, nausea, and vomiting. In the levonorgestrel-containing patch trial, patch users reported less vomiting, headaches, and fatigue.Of 11 ring trials with discontinuation data, two showed the ring group discontinued less than the COC group: OR 0.32 (95% CI 0.16 to 0.66) and OR 0.52 (95% CI 0.31 to 0.88). Ring users were less likely to discontinue due to adverse events in one study (OR 0.32; 95% CI 0.15 to 0.70). Compared to the COC users, ring users had more vaginitis and leukorrhea but less vaginal dryness. Ring users also reported less nausea, acne, irritability, depression, and emotional lability than COC users.For cycle control, only one trial study showed a significant difference. Women in the patch group were less likely to have breakthrough bleeding and spotting. Seven ring studies had bleeding data; four trials showed the ring group generally had better cycle control than the COC group. Effectiveness was not significantly different for the methods compared. Pregnancy data were available from half of the patch trials but two-thirds of ring trials. The patch could lead to more discontinuation than the COC. The patch group had better compliance than the COC group. Compliance data came from half of the patch studies and one-third of the ring trials. Patch users had more side effects than the COC group. Ring users generally had fewer adverse events than COC users but more vaginal irritation and discharge.The quality of the evidence for this review was considered low for the patch and moderate for the ring. The main reasons for downgrading were lack of information on the randomization sequence generation or allocation concealment, the outcome assessment methods, high losses to follow up, and exclusions after randomization.
Patched-grid calculations with the Euler and Navier-Stokes equations: Theory and applications
NASA Technical Reports Server (NTRS)
Rai, M. M.
1986-01-01
A patched-grid approach is one in which the flow region of interest is divided into subregions which are then discretized independently using existing grid generator. The equations of motion are integrated in each subregion in conjunction with patch-boundary schemes which allow proper information transfer across interfaces that separate subregions. The patched-grid approach greatly simplifies the treatment of complex geometries and also the addition of grid points to selected regions of the flow. A conservative patch-boundary condition that can be used with explicit, implicit factored and implicit relaxation schemes is described. Several example calculations that demonstrate the capabilities of the patched-grid scheme are also included.
Implementation for wideband applications using UWB fractal patch antenna
NASA Astrophysics Data System (ADS)
Kumar, D. Naresh
2018-04-01
This paper defines in detail about the diverse fractal patch antenna. Microstrip patch antennas has evolved in the field of research and development extending its impact across wide range of applications. A combination of patch antenna with fractal patterns has become a tryout to outspread it further. Because of its low profile nature patch antennas have added to a lot of prominence. Apart from have this property it can also be renovated further for wide bandwidth (2929 MHz) applications, as it exhibits self-analogous property. This antenna is premeditated on a patch using Sierpinski(4.040 GHz, 6.566 GHz) and Koch fractal geometries respectively. The antenna is designed using HFSS software.
Long-term results of pulmonary valve annular enlargement with valve repair in tetralogy of Fallot.
Kim, Hyungtae; Sung, Si Chan; Choi, Kwang Ho; Lee, Hyoung Doo; Kim, Geena; Ko, Hoon; Lee, Young Seok
2018-06-01
We adopted an operative technique of pulmonary valve (PV) annular enlargement with valve repair in tetralogy of Fallot (TOF) correction to reduce postoperative pulmonary regurgitation (PR) 16 years ago. Here, we have evaluated the long-term results. Between April 2000 and August 2005, 43 patients (26 men) with tetralogy of Fallot with pulmonary stenosis underwent PV annular enlargement with valve repair. The median age and body weight at the time of surgery were 14 months and 10.2 kg, respectively. There was no operative mortality. Mean postoperative PR grade at discharge was 0.93 ± 0.40 (none or trivial in 10 patients, mild in 27 patients, mild to moderate in 5 patients and moderate in 1 patient), and the mean postoperative pressure gradient across PV was 13.0 ± 10.9 mmHg. The mean follow-up duration was 131.9 ± 42.9 months. During follow-up, 1 reoperation was performed for residual ventricular septal defect. The mean PR grade at the last follow-up echocardiography was 1.59 ± 0.60 (mild in 17 patients, mild to moderate in 8 patients, moderate in 14 patients, moderate to severe in 1 patient and severe in 3 patients), and the mean pressure gradient was 22.7 ± 9.9 mmHg. We have compared the incidence of moderate or more PR with the incidence of patients who underwent simple transannular patch enlargement through propensity score matching. The PV repair group had a lower incidence of moderate or more PR compared with the simple transannular patch group (40% vs 68%, P = 0.04). PV annular enlargement with valve repair has reasonable long-term results and yields a lower long-term incidence of significant PR compared with the simple transannular patch enlargement technique.
MS lesion segmentation using a multi-channel patch-based approach with spatial consistency
NASA Astrophysics Data System (ADS)
Mechrez, Roey; Goldberger, Jacob; Greenspan, Hayit
2015-03-01
This paper presents an automatic method for segmentation of Multiple Sclerosis (MS) in Magnetic Resonance Images (MRI) of the brain. The approach is based on similarities between multi-channel patches (T1, T2 and FLAIR). An MS lesion patch database is built using training images for which the label maps are known. For each patch in the testing image, k similar patches are retrieved from the database. The matching labels for these k patches are then combined to produce an initial segmentation map for the test case. Finally a novel iterative patch-based label refinement process based on the initial segmentation map is performed to ensure spatial consistency of the detected lesions. A leave-one-out evaluation is done for each testing image in the MS lesion segmentation challenge of MICCAI 2008. Results are shown to compete with the state-of-the-art methods on the MICCAI 2008 challenge.
Chen, Jennifer K; Jacob, Sharon E; Nedorost, Susan T; Hanifin, Jon M; Simpson, Eric L; Boguniewicz, Mark; Watsky, Kalman L; Lugo-Somolinos, Aida; Hamann, Carsten R; Eberting, Cheryl Lee; Silverberg, Jonathan I; Thyssen, Jacob P
2016-01-01
Allergic contact dermatitis (ACD) may complicate the clinical course of atopic dermatitis (AD), and patch testing remains the criterion standard for diagnosing ACD. To date, there have been no guidelines or consensus recommendations on when and how to patch test individuals with AD. Failure to patch test when appropriate may result in overlooking an important and potentially curable complicating comorbidity. In this article, we present consensus recommendations regarding when to perform patch testing in the AD patient, best practices, and common pitfalls. Patch testing should be considered in AD patients with dermatitis that fails to improve with topical therapy; with atypical/changing distribution of dermatitis, or pattern suggestive of ACD; with therapy-resistant hand eczema in the working population; with adult- or adolescent-onset AD; and/or before initiating systemic immunosuppressants for the treatment of dermatitis. A suggested patch testing algorithm for AD patients is provided.
Lee, Hansang; Hong, Helen; Kim, Junmo; Jung, Dae Chul
2018-04-01
To develop an automatic deep feature classification (DFC) method for distinguishing benign angiomyolipoma without visible fat (AMLwvf) from malignant clear cell renal cell carcinoma (ccRCC) from abdominal contrast-enhanced computer tomography (CE CT) images. A dataset including 80 abdominal CT images of 39 AMLwvf and 41 ccRCC patients was used. We proposed a DFC method for differentiating the small renal masses (SRM) into AMLwvf and ccRCC using the combination of hand-crafted and deep features, and machine learning classifiers. First, 71-dimensional hand-crafted features (HCF) of texture and shape were extracted from the SRM contours. Second, 1000-4000-dimensional deep features (DF) were extracted from the ImageNet pretrained deep learning model with the SRM image patches. In DF extraction, we proposed the texture image patches (TIP) to emphasize the texture information inside the mass in DFs and reduce the mass size variability. Finally, the two features were concatenated and the random forest (RF) classifier was trained on these concatenated features to classify the types of SRMs. The proposed method was tested on our dataset using leave-one-out cross-validation and evaluated using accuracy, sensitivity, specificity, positive predictive values (PPV), negative predictive values (NPV), and area under receiver operating characteristics curve (AUC). In experiments, the combinations of four deep learning models, AlexNet, VGGNet, GoogleNet, and ResNet, and four input image patches, including original, masked, mass-size, and texture image patches, were compared and analyzed. In qualitative evaluation, we observed the change in feature distributions between the proposed and comparative methods using tSNE method. In quantitative evaluation, we evaluated and compared the classification results, and observed that (a) the proposed HCF + DF outperformed HCF-only and DF-only, (b) AlexNet showed generally the best performances among the CNN models, and (c) the proposed TIPs not only achieved the competitive performances among the input patches, but also steady performance regardless of CNN models. As a result, the proposed method achieved the accuracy of 76.6 ± 1.4% for the proposed HCF + DF with AlexNet and TIPs, which improved the accuracy by 6.6%p and 8.3%p compared to HCF-only and DF-only, respectively. The proposed shape features and TIPs improved the HCFs and DFs, respectively, and the feature concatenation further enhanced the quality of features for differentiating AMLwvf from ccRCC in abdominal CE CT images. © 2018 American Association of Physicists in Medicine.
Space Science Investigation: NASA ISS Stowage Simulator
NASA Technical Reports Server (NTRS)
Crawford, Gary
2017-01-01
During this internship the opportunity was granted to work with the Integrated, Graphics, Operations and Analysis Laboratory (IGOAL) team. The main assignment was to create 12 achievement patches for the Space Station training simulator called the "NASA ISS Stowage Training Game." This project was built using previous IGOAL developed software. To accomplish this task, Adobe Photoshop and Adobe Illustrator were used to craft the badges and other elements required. Blender, a 3D modeling software, was used to make the required 3D elements. Blender was a useful tool to make things such as a CTB bag for the "No More Bob" patch which shows a gentleman kicking a CTB bag into the distance. It was also used to pose characters to the positions that was optimal for their patches as in the "Station Sanitation" patch which portrays and astronaut waving on a U.S module on a truck. Adobe Illustrator was the main piece of software for this task. It was used to craft the badges and upload them when they were completed. The style of the badges were flat, meaning that they shouldn't look three dimensional in any way, shape or form. Adobe Photoshop was used when any pictures need brightening and was where the texture for the CTB bag was made. In order for the patches to be ready for the game's next major release, they have to go under some critical reviewing, revising and re-editing to make sure the other artists and the rest of the staff are satisfied with the final products. Many patches were created and revamped to meet the flat setting and incorporate suggestions from the IGOAL team. After the three processes were completed, the badges were implemented into the game (reference fig1 for badges). After a month of designing badges, the finished products were placed into the final game build via the programmers. The art was the final piece in showcasing the latest build to the public for testing. Comments from the testers were often exceptional and the feedback on the badges were outstanding. The latest build will also be tested by astronauts to determine if the product could potentially be incorporated into the astronaut training program. This experience has provided the opportunity to experience the feeling of working with research and development organization. The art skills and programming skills received at the internship will provide and maintain and strong foundation for a career in computer programming and digital media.
Forest Patch Size, Land Use, and Mesic Forest Herbs in the French Broad River Basin, North Carolina
Scott M. Pearson; Alan B. Smith; Monica G. Turner
1998-01-01
The effect of forest fragmentation on cove-forest herbs was studied in the Southern Blue Ridge Province. Patches of mesic forests were sampled with 4 ha study plots. The coverage and density of herb species were greater in large patches (>200 ha) than in small patches (
Fentanyl patches: preventable overdose.
2010-02-01
Fentanyl is a potent opioid analgesic marketed for the treatment of stable intense chronic pain, particularly in the form of a transdermal patch. These delivery devices carry the same risk of adverse effects and drug interactions as conventional formulations of opioids. The patches carry an added risk of fentanyl overdose because they contain very high doses, both before and after use. High-risk situations for overdose were identified by examining the results of pharmacovigilance studies and medication error prevention programmes, as well as an observational study, case reports, and a French legal action. The main situations exposing patients to a risk of overdose are: confusion between two dose strengths, forgetting to remove the patch; accidental transfer of the patch to another person, application of more than one patch, cutting the patches, self-medication, and ingestion. Increased skin temperature facilitates fentanyl absorption and thus increases the risk of overdose; high-risk situations include fever, electric blankets, and intense physical exercise. In practice, the precautions for treatment and patch disposal must be followed exactly if this delivery system is to serve as a valid alternative to morphine for selected patients with stable intense chronic pain.
A Real-Time Telemetry Simulator of the IUS Spacecraft
NASA Technical Reports Server (NTRS)
Drews, Michael E.; Forman, Douglas A.; Baker, Damon M.; Khazoyan, Louis B.; Viazzo, Danilo
1998-01-01
A real-time telemetry simulator of the IUS spacecraft has recently entered operation to train Flight Control Teams for the launch of the AXAF telescope from the Shuttle. The simulator has proven to be a successful higher fidelity implementation of its predecessor, while affirming the rapid development methodology used in its design. Although composed of COTS hardware and software, the system simulates the full breadth of the mission: Launch, Pre-Deployment-Checkout, Burn Sequence, and AXAF/IUS separation. Realism is increased through patching the system into the operations facility to simulate IUS telemetry, Shuttle telemetry, and the Tracking Station link (commands and status message).
Wang, Quanxin; Tanigawa, Hisashi; Fujita, Ichiro
2017-04-01
Two distinct areas along the ventral visual stream of monkeys, the primary visual (V1) and inferior temporal (TE) cortices, exhibit different projection patterns of intrinsic horizontal axons with patchy terminal fields in adult animals. The differences between the patches in these 2 areas may reflect differences in cortical representation and processing of visual information. We studied the postnatal development of patches by injecting an anterograde tracer into TE and V1 in monkeys of various ages. At 1 week of age, labeled patches with distribution patterns reminiscent of those in adults were already present in both areas. The labeling intensity of patches decayed exponentially with projection distance in monkeys of all ages in both areas, but this trend was far less evident in TE. The number and extent of patches gradually decreased with age in V1, but not in TE. In V1, axonal and bouton densities increased postnatally only in patches with short projection distances, whereas in TE this density change occurred in patches with various projection distances. Thus, patches with area-specific distribution patterns are formed early in life, and area-specific postnatal developmental processes shape the connectivity of patches into adulthood. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Relative abundance of mesopredators and size of oak patches in the cross-timbers ecoregion
Disney, M.R.; Hellgren, E.C.; Davis, C.A.; Leslie, David M.; Engle, David M.
2008-01-01
Mesopredators (e.g., raccoon Procyon lotor, Virginia opossum Didelphis virginiana, striped skunk Mephitis mephitis) have received considerable attention because of links to population declines in birds via increased nest predation, especially in landscapes fragmented by anthropogenic forces. Relationships of abundance of mesopredators to size of habitat patches have received less attention than relationships to other metrics of fragmentation, particularly edge characteristics. We tested the hypothesis that relative abundance of mesopredators (e.g., raccoons and Virginia opossums) was related negatively to size of forest patch. We delineated 15 patches of oak (Quercus) forest ranging from 0.2 to 55.3 ha within a grassland-woodland mosaic in the cross-timbers ecoregion of Oklahoma. Scent stations and live traps within these patches were used to index relative abundance of mesopredators in summers 2003 and 2004. Both indices of relative abundance were related weakly and negatively to area of forest patch. However, rate of capture and visitation to scent station were not correlated consistently throughout the study. Our results suggested that the two methods to index abundance provided separate information on functional and numerical responses to size of patch. Our evidence that mesopredators within the cross timbers were more likely to be in smaller patches of oak forest may have implications to success of avian nesting in these patches.
Kaur, Amanpreet; Kaur, Gurpreet
2011-01-01
The study was designed to develop bioadhesive patches of carvedilol hydrochloride using chitosan (CH) and pectin (PE) interpolymer complexes and to systematically evaluate their in vitro and in vivo performances. Mucoadhesive buccal patches of carvedilol were prepared using solvent casting method. The physicochemical interaction between CH and PE was investigated by FTIR and DSC studies. The patches were evaluated for their physical characteristics like mass variation, content uniformity, folding endurance, ex vivo mucoadhesion strength, ex vivo mucoadhesion time, surface pH, in vitro drug release, in situ release study, and in vivo bioavailability study. The swelling index of the patches was found to be proportional to the PE concentration. The surface pH of all the formulated bioadhesive patches was found to lie between 6.2 and 7.2. The optimized bioadhesive patch (C1, CH:PE 20:80) showed bioadhesive strength of 22.10 ± 0.20 g, in vitro release of 98.73% and ex vivo mucoadhesion time of 451 min with in a period of 8 h. The optimized patch demonstrated good in vitro and in vivo results. The buccal delivery of carvedilol in rabbits showed a significant improvement in bioavailability of carvedilol from patches when compared to oral route. PMID:23960773
Kaur, Amanpreet; Kaur, Gurpreet
2012-01-01
The study was designed to develop bioadhesive patches of carvedilol hydrochloride using chitosan (CH) and pectin (PE) interpolymer complexes and to systematically evaluate their in vitro and in vivo performances. Mucoadhesive buccal patches of carvedilol were prepared using solvent casting method. The physicochemical interaction between CH and PE was investigated by FTIR and DSC studies. The patches were evaluated for their physical characteristics like mass variation, content uniformity, folding endurance, ex vivo mucoadhesion strength, ex vivo mucoadhesion time, surface pH, in vitro drug release, in situ release study, and in vivo bioavailability study. The swelling index of the patches was found to be proportional to the PE concentration. The surface pH of all the formulated bioadhesive patches was found to lie between 6.2 and 7.2. The optimized bioadhesive patch (C1, CH:PE 20:80) showed bioadhesive strength of 22.10 ± 0.20 g, in vitro release of 98.73% and ex vivo mucoadhesion time of 451 min with in a period of 8 h. The optimized patch demonstrated good in vitro and in vivo results. The buccal delivery of carvedilol in rabbits showed a significant improvement in bioavailability of carvedilol from patches when compared to oral route.
Pharmacokinetic Evaluation of Two Nicotine Patches in Smokers.
Rasmussen, Scott; Horkan, Kathleen Halabuk; Kotler, Mitchell
2018-02-02
Smoking continues to be a major preventable cause of early mortality worldwide, and nicotine replacement therapy has been demonstrated to increase rates of abstinence among smokers attempting to quit. Nicotine transdermal systems (also known as nicotine patches) attach to the skin via an adhesive layer composed of a mixture of different-molecular-weight polyisobutylenes (PIBs) in a specific ratio. This randomized, single-dose, 2-treatment, crossover pharmacokinetic (PK) trial assessed the bioequivalence of nicotine patches including a replacement PIB adhesive (test) compared with the PIB adhesive historically used on marketed patches (reference). The test and reference patches were bioequivalent, as determined by the PK parameters of C max and AUC 0-t . In addition, the parameters T max and t 1/2 did not significantly differ between the 2 patches, supporting the bioequivalence finding from the primary analysis. The tolerability profiles of the patches containing the replacement and previously used PIB adhesives were similar; application-site adverse events did not significantly differ between test and reference patches. Overall, these data establish the bioequivalence of the nicotine patch with the replacement PIB adhesive formulation and the previously utilized PIB adhesive formulation. © 2018 The Authors. Clinical Pharmacology in Drug Development published by Wiley Periodicals, Inc. on behalf of The American College of Clinical Pharmacology.
Fischer, Louise Arup; Voelund, Aage; Andersen, Klaus Ejner; Menné, Torkil; Johansen, Jeanne Duus
2009-10-01
Allergic contact dermatitis is common and can be prevented. The relationship between thresholds for patch tests and the repeated open application test (ROAT) is unclear. It would be desirable if patch test and ROAT data from already sensitized individuals could be used in prevention. The aim was to develop an equation that could predict the response to an allergen in a ROAT based on the dose-response curve derived by patch testing. Results from two human experimental elicitation studies with non-volatile allergens, nickel and the preservative methyldibromo glutaronitrile (MDBGN), were analysed by logistic dose-response statistics. The relation for volatile compounds was investigated using the results from experiments with the fragrance chemicals hydroxyisohexyl 3-cyclohexene carboxaldehyde and isoeugenol. For non-volatile compounds, the outcome of a ROAT can be estimated from the patch test by: ED(xx)(ROAT) = 0.0296 ED(xx)(patch test). For volatile compounds, the equation predicts that the response in the ROAT is more severe than the patch test response, but it overestimates the response. This equation may be used for non-volatile compounds other than nickel and MDBGN, after further validation. The relationship between the patch test and the ROAT can be used for prevention, to set safe levels of allergen exposure based on patch test data.
Results of patch testing in 10 patients with peristomal dermatitis.
Landis, Megan N; Keeling, James H; Yiannias, James A; Richardson, Donna M; Nordberg Linehan, Diane L; Davis, Mark D P
2012-09-01
Peristomal dermatitis is a common problem in patients with ostomies that is a source of considerable morbidity. Irritant contact dermatitis is most common, but allergic contact dermatitis can also occur. Because of the lack of published reports on patch testing for this indication, we undertook a retrospective study of patch testing results in patients with suspected peristomal allergic contact dermatitis. We sought to describe our patch testing experience with patients referred with peristomal dermatitis. This was a retrospective review of medical records of patients with ostomies and peristomal dermatitis who underwent patch testing in the Mayo Clinic Departments of Dermatology in Jacksonville, FL; Rochester, MN; and Scottsdale, AZ, during a 10-year period (2000-2010). Ten patients with peristomal dermatitis were referred for patch testing (6 in Minnesota, 2 in Florida, and 2 in Arizona). Patients were patch tested to the materials used in their stoma devices, to the standard series, and in some cases to supplemental series. All 10 had at least one allergic patch test reaction, most commonly to stoma paste (3 of 10 patients). Retrospective nature of study via chart review is a limitation. Patch testing is a useful tool for identification of allergens in patients with peristomal dermatitis. Copyright © 2011 American Academy of Dermatology, Inc. Published by Mosby, Inc. All rights reserved.
Lee, Soo-Han; Kim, Seung-Hyun; Noh, Yook-Hwan; Choi, Byung-Moon; Noh, Gyu-Jeong; Park, Woo-Dae; Kim, Eun-Jung; Cho, Ik-Hyun; Bae, Chun-Sik
2016-02-01
Memantine is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist used to treat Alzheimer's disease. We investigated memantine pharmacokinetics after oral, IV and patch administration in rats, and compared memantine pharmacokinetics after multiple- or single-dose oral and transdermal administration. Venous blood was collected at preset intervals in single- and multiple-dose studies. Non-compartmental pharmacokinetics was analysed for all formulations. The oral, IV and patch memantine doses were 10 mg/kg, 2 mg/kg and 8.21 ± 0.89 mg/kg, respectively. The maximum plasma concentration was lower and the half-life longer after patch administration than oral and IV administration. Memantine bioavailability was 41 and 63% for oral and patch administration, respectively. Steady state was achieved around 24 hr for oral and patch administration. The mean AUC increased after oral or patch administration from single to multiple dose. The memantine patch formulation displayed a longer duration of action and lower peak plasma concentration. However, drug exposure was similar to the oral formulation at each dose. Additionally, the memantine patch formulation displayed a smaller interindividual variability and lower accumulation than the oral formulation. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).
Rotator cuff repair with a tendon-fibrocartilage-bone composite bridging patch.
Ji, Xiaoxi; Chen, Qingshan; Thoreson, Andrew R; Qu, Jin; An, Kai-Nan; Amadio, Peter C; Steinmann, Scott P; Zhao, Chunfeng
2015-11-01
To compare the mechanical performance of a rotator cuff repaired with a novel tendon-fibrocartilage-bone composite bridging patch vs the traditional Mason-Allen repair in an in vitro canine model. Twenty shoulders and 10 bridging patches from patellar tendon were harvested. The patches were trimmed and sliced into 2 layers. An infraspinatus tendon tear was created in each shoulder. Modified Mason-Allen sutures were used to repair the infraspinatus tendon to the greater tuberosity, with or without the bridging patch (bridging patch group and controls, respectively). Shoulders were loaded to failure under displacement control at a rate of 0.5mm/s. The ultimate tensile load was significantly higher in the bridging patch group than control (mean [SD], 365.46 [36.45] vs 272.79 [48.88] N; P<.001). Stiffness at the greater tuberosity repair site and the patch-infraspinatus tendon repair site was significantly higher than the control repair site (93.96 [27.72] vs 42.62 [17.48] N/mm P<.001; 65.94 [24.51] vs 42.62 [17.48] N/mm P=.02, respectively). The tendon-fibrocartilage-bone composite bridging patch achieved higher ultimate tensile load and stiffness at the patch-greater tuberosity repair site compared with traditional repair in a canine model. This composite tissue transforms the traditional tendon-to-bone healing interface (with dissimilar tissues) into a pair of bone-to-bone and tendon-to-tendon interfaces, which may improve healing quality and reduce retear rate. Copyright © 2015 Elsevier Ltd. All rights reserved.
Integration of autopatching with automated pipette and cell detection in vitro
Wu (吴秋雨), Qiuyu; Kolb, Ilya; Callahan, Brendan M.; Su, Zhaolun; Stoy, William; Kodandaramaiah, Suhasa B.; Neve, Rachael; Zeng, Hongkui; Boyden, Edward S.; Forest, Craig R.
2016-01-01
Patch clamp is the main technique for measuring electrical properties of individual cells. Since its discovery in 1976 by Neher and Sakmann, patch clamp has been instrumental in broadening our understanding of the fundamental properties of ion channels and synapses in neurons. The conventional patch-clamp method requires manual, precise positioning of a glass micropipette against the cell membrane of a visually identified target neuron. Subsequently, a tight “gigaseal” connection between the pipette and the cell membrane is established, and suction is applied to establish the whole cell patch configuration to perform electrophysiological recordings. This procedure is repeated manually for each individual cell, making it labor intensive and time consuming. In this article we describe the development of a new automatic patch-clamp system for brain slices, which integrates all steps of the patch-clamp process: image acquisition through a microscope, computer vision-based identification of a patch pipette and fluorescently labeled neurons, micromanipulator control, and automated patching. We validated our system in brain slices from wild-type and transgenic mice expressing channelrhodopsin 2 under the Thy1 promoter (line 18) or injected with a herpes simplex virus-expressing archaerhodopsin, ArchT. Our computer vision-based algorithm makes the fluorescent cell detection and targeting user independent. Compared with manual patching, our system is superior in both success rate and average trial duration. It provides more reliable trial-to-trial control of the patching process and improves reproducibility of experiments. PMID:27385800
Sheng, Sheng; Ling, Meng; Fu-An, Wu; Baoping, Li
2015-01-01
Foraging parasitoids often must estimate local risk of predation just as they must estimate local patch value. Here, we investigate the effects a generalist predator Chlaenius bioculatus (Coleoptera: Carabidae), has on the oviposition behavior and the patch residence decisions of a solitary parasitoid Meteorus pulchricornis (Hymenoptera: Braconidae) in response to the varying host quality of Spodoptera litura (Lepidoptera: Noctuidae) larvae (L2 and L4). M. pulchricornis attacked more L4 than on L2 hosts, with the difference in attack rate varying depending on predation treatments, greater in the presence (either actively feeding or not) of the predator than in the absence of it. The parasitoid attacked fewer L2 and L4 hosts when the predator was actively feeding than when it was not feeding or not present in the patch. M. pulchricornis decreased the patch leaving tendency with increasing rejections of hosts, but increased the tendency in response to the presence of the predator as compared with the absence of it, and furthermore, increased the patch leaving tendency when the predator was actively feeding as compared with when it was not. Our study suggests that M. pulchricornis can exploit high quality patches while minimizing predation risk, by attacking more hosts in high quality patches while reducing total patch time in response to risk of predation. © The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.
Assessment of optimal strategies in a two-patch dengue transmission model with seasonality
Lee, Chang Hyeong; Lee, Sunmi
2017-01-01
Emerging and re-emerging dengue fever has posed serious problems to public health officials in many tropical and subtropical countries. Continuous traveling in seasonally varying areas makes it more difficult to control the spread of dengue fever. In this work, we consider a two-patch dengue model that can capture the movement of host individuals between and within patches using a residence-time matrix. A previous two-patch dengue model without seasonality is extended by adding host demographics and seasonal forcing in the transmission rates. We investigate the effects of human movement and seasonality on the two-patch dengue transmission dynamics. Motivated by the recent Peruvian dengue data in jungle/rural areas and coast/urban areas, our model mimics the seasonal patterns of dengue outbreaks in two patches. The roles of seasonality and residence-time configurations are highlighted in terms of the seasonal reproduction number and cumulative incidence. Moreover, optimal control theory is employed to identify and evaluate patch-specific control measures aimed at reducing dengue prevalence in the presence of seasonality. Our findings demonstrate that optimal patch-specific control strategies are sensitive to seasonality and residence-time scenarios. Targeting only the jungle (or endemic) is as effective as controlling both patches under weak coupling or symmetric mobility. However, focusing on intervention for the city (or high density areas) turns out to be optimal when two patches are strongly coupled with asymmetric mobility. PMID:28301523
Horner, Kristen A; Noble, Erika S; Gilbert, Yamiece E
2010-06-01
Amphetamines induce stereotypy, which correlates with patch-enhanced c-Fos expression the patch compartment of caudate putamen (CPu). Methamphetamine (METH) treatment also induces patch-enhanced expression of prodynorphin (PD), arc and zif/268 in the CPu. Whether patch-enhanced activation of any of these genes correlates with METH-induced stereotypy is unknown, and the factors that contribute to this pattern of expression are poorly understood. Activation of mu opioid receptors, which are expressed by the neurons of the patch compartment, may underlie METH-induced patch-enhanced gene expression and stereotypy. The current study examined whether striatal mu opioid receptor blockade altered METH-induced stereotypy and patch-enhanced gene expression, and if there was a correlation between the two responses. Animals were intrastriatally infused with the mu antagonist CTAP (10 microg/microl), treated with METH (7.5 mg/kg, s.c.), placed in activity chambers for 3h, and then sacrificed. CTAP pretreatment attenuated METH-induced increases in PD, arc and zif/268 mRNA expression and significantly reduced METH-induced stereotypy. Patch-enhanced PD and arc mRNA expression in the dorsolateral CPu correlated negatively with METH-induced stereotypy. These data indicate that mu opioid receptor activation contributes to METH-induced gene expression in the CPu and stereotypy, and that patch-enhanced PD and arc expression may be a homeostatic response to METH treatment. Copyright 2010 Elsevier Inc. All rights reserved.
Horner, Kristen A.; Noble, Erika S.; Gilbert, Yamiece E.
2010-01-01
Amphetamines induce stereotypy, which correlates with patch-enhanced c-Fos expression the patch compartment of caudate putamen (CPu). Methamphetamine (METH) treatment also induces patch-enhanced expression of prodynorphin (PD), arc and zif/268 in the CPu. Whether patch-enhanced activation of any of these genes correlates with METH-induced stereotypy is unknown, and the factors that contribute to this pattern of expression are poorly understood. Activation of mu opioid receptors, which are expressed by the neurons of the patch compartment, may underlie METH-induced patch-enhanced gene expression and stereotypy. The current study examined whether striatal mu opioid receptor blockade altered METH-induced stereotypy and patch-enhanced gene expression, and if there was a correlation between the two responses. Animals were intrastriatally infused with the mu antagonist CTAP (10 μg/μl), treated with METH (7.5 mg/kg, s.c.), placed in activity chambers for 3h, and then sacrificed. CTAP pretreatment attenuated METH-induced increases in PD, arc and zif/268 mRNA expression and significantly reduced METH-induced stereotypy. Patch-enhanced PD and arc mRNA expression in the dorsolateral CPu correlated negatively with METH-induced stereotypy. These data indicate that mu opioid receptor activation contributes to METH-induced gene expression in the CPu and stereotypy, and that patch-enhanced PD and arc expression may be a homeostatic response to METH treatment. PMID:20298714
Jensen, T S; Høye, K; Fricová, J; Vanelderen, P; Ernault, E; Siciliano, T; Marques, S
2014-10-01
Application of the capsaicin 8% patch is associated with treatment-related discomfort. Consequently, pretreatment for 60 min with anaesthetic cream is recommended; however, this may be uncomfortable and time consuming. We conducted a multicentre, randomized (1:1), assessor-blinded study in patients with peripheral neuropathic pain to assess tolerability of the capsaicin patch following topical lidocaine (4%) or oral tramadol (50 mg) pretreatment. The primary endpoint was the proportion of patients tolerating capsaicin patch application (ability to receive ≥90% of a 60-min application). Numeric Pain Rating Scale (NPRS) scores were assessed before, during and after treatment. Overall, 122 patients were included (61 per arm). The capsaicin patch was tolerated by 121 patients. Tolerability of the capsaicin patch was similar following pretreatment with lidocaine and tramadol. Following patch application, pain levels increased up to 55 min (change from baseline of 1.3 for lidocaine and 1.4 for tramadol). After patch removal, tramadol-treated patients experienced greater pain relief up to the end of day 1; in the evening, mean changes in NPRS scores from baseline were 0 for lidocaine and -1 for tramadol. Proportions of patients reporting increases of ≥2 NPRS points or >33% from baseline at one or more time point(s) on the day of treatment were similar between arms. Adverse event incidence was comparable between arms. Capsaicin 8% patch tolerability was similar in the two arms, with comparable results for most secondary endpoints. Tramadol given 30 min before patch application should be considered as an alternative pretreatment option in patients receiving capsaicin patch treatment. © 2014 The Authors. European Journal of Pain published by John Wiley & Sons Ltd on behalf of European Pain Federation - EFIC®.
NASA Astrophysics Data System (ADS)
Tape, K. D.; Hallinger, M.; Buras, A.; Wilmking, M.
2013-12-01
Over the last decade, evidence has emerged for a circumarctic trend of increasing shrub cover in tundra regions. On the Alaskan tundra, repeat photography has shown spatial differences in shrub patch dynamics: since 1950, most patches expanded while some remained stable. In this study we explore the underpinnings of this landscape heterogeneity by sampling the three dominant shrubs of the Alaskan tundra--alder, willow and birch--and creating shrub ring width chronologies to determine the influence of climate variability on shrub growth. Shrubs of expanding patches of all three species grew at higher rates than shrubs of stable patches. Alder and willow shrubs in expanding patches exhibited mainly positive growth trends, while their counterparts in stable patches exhibited mainly negative growth trends. Birch shrub growth declined in expanding and stable patches. Alder and willow shrub growth rates and responses to climate were controlled more by soil characteristics than by their genus; expanding alder and willow shrubs showed significant positive correlations with spring and summer temperatures, whereas alder and willow shrubs of stable patches were negatively influenced by winter precipitation. The widely-scattered stable shrub patches sampled here are considered ';moist tussock tundra,' which covers 13.4% of the low arctic landscape. In moist tussock tundra, and presumably also wet tussock tundra, the negative influence of deeper snow on shrubs outweighed the positive influence of deeper snow on ground temperature and nutrient stocks articulated by the snow-shrub-microbe hypothesis. Thus, while shrubs of expanding patches have generally profited from warmer summers, shrubs of stable patches have suffered from increased soil moisture resulting from increased snowmelt water. These results underscore the spatial and temporal complexity in shrub-climate dynamics, which will require considerable finesse to appropriately integrate into modeling efforts.
Effect of Landscape Pattern on Insect Species Density within Urban Green Spaces in Beijing, China
Su, Zhimin; Li, Xiaoma; Zhou, Weiqi; Ouyang, Zhiyun
2015-01-01
Urban green space is an important refuge of biodiversity in urban areas. Therefore, it is crucial to understand the relationship between the landscape pattern of green spaces and biodiversity to mitigate the negative effects of urbanization. In this study, we collected insects from 45 green patches in Beijing during July 2012 using suction sampling. The green patches were dominated by managed lawns, mixed with scattered trees and shrubs. We examined the effects of landscape pattern on insect species density using hierarchical partitioning analysis and partial least squares regression. The results of the hierarchical partitioning analysis indicated that five explanatory variables, i.e., patch area (with 19.9% independent effects), connectivity (13.9%), distance to nearest patch (13.8%), diversity for patch types (11.0%), and patch shape (8.3%), significantly contributed to insect species density. With the partial least squares regression model, we found species density was negatively related to patch area, shape, connectivity, diversity for patch types and proportion of impervious surface at the significance level of p < 0.05 and positively related to proportion of vegetated land. Regression tree analysis further showed that the highest species density was found in green patches with an area <500 m2. Our results indicated that improvement in habitat quality, such as patch area and connectivity that are typically thought to be important for conservation, did not actually increase species density. However, increasing compactness (low-edge) of patch shape and landscape composition did have the expected effect. Therefore, it is recommended that the composition of the surrounding landscape should be considered simultaneously with planned improvements in local habitat quality. PMID:25793897
Lee, Ya-Fu; Kuo, Yen-Min; Chu, Wen-Chen
2016-01-01
When facing a novel situation, animals can retreat or leave to avoid risks, but will miss potential resources and opportunities. Alternatively they may reduce environmental uncertainty by exploration, while risking no energy rewards and exposure to hazards, and use the information retrieved for subsequent decision making. When exploring, however, animals may adopt different tactics according to individual states. We tested that energy states will affect exploratory behavior by experimenting with wild-caught untrained Eurasian tree sparrows ( Passer montanus ) in fasted or fed states exploring in a novel space with hidden food supply in different patch distribution patterns. Our data revealed that fasted sparrows risked being earlier explorers more often, initiated more exploratory bouts before patches were found, and stayed longer on the ground under both patch patterns. Fasted sparrows discovered more patches and consumed more food than fed sparrows in dispersed, but not necessary so in clumped, patch patterns; whereas fed birds also increased patch finding to a certain level in dispersed patterns. Sparrows of both energy states, however, did not differ in feeding rates in either patch pattern. Exploratory behavior of tree sparrows is state-dependent, which supports our prediction that birds with an energy shortage will be risk-prone and explore more readily. Our study also indicates a game nature of tree sparrow exploratory behavior in a group context when explorers are in different energy states and are exposed to different patch distributions. Birds of lower energy state adopting an active exploring tactic may be favored by obtaining higher energy gains in dispersed patch patterns with lower patch richness. More satiated birds, however, achieved a similar feeding rate by lowered exposure time.
Low-dose levonorgestrel and ethinyl estradiol patch and pill: a randomized controlled trial.
Kaunitz, Andrew M; Portman, David; Westhoff, Carolyn L; Archer, David F; Mishell, Daniel R; Rubin, Arkady; Foegh, Marie
2014-02-01
To compare a new low-dose levonorgestrel and ethinyl estradiol contraceptive patch (Patch) with a combination oral contraceptive (Pill; 100 micrograms levonorgestrel, 20 micrograms ethinyl estradiol) regarding efficacy, safety, compliance, and unscheduled uterine bleeding. Women (17-40 years; body mass index 16-60) were randomized in a 3:1 ratio to one of two groups: Patch only (13 cycles) or Pill (six cycles) followed by Patch (seven cycles). Investigators evaluated adverse events during cycles 2, 4, 6, 9, and 13. Participants recorded drug administration and uterine bleeding on daily diary cards. Compliance was assessed by measuring levonorgestrel and ethinyl estradiol plasma levels. Pearl Index (pregnancies per 100 woman-years) was calculated to evaluate efficacy. Participants (N=1,504) were randomized to Patch (n=1,129) or Pill (n=375). Approximately 30% were obese, more than 40% were racial or ethnic minorities, and more than 55% were new users of hormonal contraceptives. Laboratory-verified noncompliance (undetectable plasma drug levels) was 11% of Patch and 12.6% of Pill users at cycle 6. Pearl Indices (95% confidence intervals) for the intention-to-treat population (cycles 1-6) were 4.45 (2.34-6.57) for Patch and 4.02 (0.50-7.53) for Pill; excluding laboratory-verified noncompliant participants, Pearl Indices were 2.82 (0.98-4.67) for Patch and 3.80 (0.08-7.52) for Pill (differences not statistically significant). Incidence of unscheduled bleeding and incidence and severity of adverse events were similar for both contraceptives (no statistically significant difference). Efficacy and safety of the new contraceptive Patch are comparable to those of a Pill. Laboratory-verified noncompliance and bleeding profile are similar between the two treatments. The Patch was well tolerated. ClinicalTrials.gov, www.clinicaltrials.gov, NCT01181479. I.
Ingalls, Nichole K; Horton, Zachary A; Bettendorf, Matthew; Frye, Ira; Rodriguez, Carlos
2010-02-01
The lidocaine patch 5% was developed to treat postherpetic neuralgia. Anecdotal experience at our institution suggests the lidocaine patch 5% decreases narcotic usage in patients with traumatic rib fractures. This trial was developed to define the patch's efficacy. Patients with rib fractures admitted to the trauma service at our Level I trauma center were enrolled and randomized in a 1 to 1 double-blind manner to receive a lidocaine patch 5% or placebo patch. Fifty-eight patients who met the inclusion criteria were enrolled from January 2007 to August 2008. Demographic and clinical information were recorded. The primary outcomes variable was total narcotic use, analyzed using the 1-tailed Mann-Whitney test. The secondary outcomes variables included non-narcotic pain medication, average pain score, pulmonary complications, and length of stay. Significance was defined based on a 1-sided test for the primary outcome and 2-sided tests for other comparisons, at p < 0.05. Thirty-three patients received the lidocaine patch 5% and 25 received the placebo patch. There were no significant differences in age, number of rib fractures, gender, trauma mechanism, preinjury lung disease, smoking history, percent of current smokers, and need for placement of chest tube between the lidocaine patch 5% and placebo groups. There was no difference between the lidocaine patch 5% and placebo groups, respectively, with regard to total IV narcotic usage: median, 0.23 units versus 0.26 units; total oral narcotics: median, 4 units versus 7 units; pain score: 5.6 +/- 0.4 versus 6.0 +/- 0.3 (mean +/- SEM); length of stay: 7.8 +/- 1.1 versus 6.2 +/- 0.7; or percentage of patients with pulmonary complications: 72.7% versus 72.0%. The lidocaine patch 5% does not significantly improve pain control in polytrauma patients with traumatic rib fractures.
Effect of landscape pattern on insect species density within urban green spaces in Beijing, China.
Su, Zhimin; Li, Xiaoma; Zhou, Weiqi; Ouyang, Zhiyun
2015-01-01
Urban green space is an important refuge of biodiversity in urban areas. Therefore, it is crucial to understand the relationship between the landscape pattern of green spaces and biodiversity to mitigate the negative effects of urbanization. In this study, we collected insects from 45 green patches in Beijing during July 2012 using suction sampling. The green patches were dominated by managed lawns, mixed with scattered trees and shrubs. We examined the effects of landscape pattern on insect species density using hierarchical partitioning analysis and partial least squares regression. The results of the hierarchical partitioning analysis indicated that five explanatory variables, i.e., patch area (with 19.9% independent effects), connectivity (13.9%), distance to nearest patch (13.8%), diversity for patch types (11.0%), and patch shape (8.3%), significantly contributed to insect species density. With the partial least squares regression model, we found species density was negatively related to patch area, shape, connectivity, diversity for patch types and proportion of impervious surface at the significance level of p < 0.05 and positively related to proportion of vegetated land. Regression tree analysis further showed that the highest species density was found in green patches with an area <500 m2. Our results indicated that improvement in habitat quality, such as patch area and connectivity that are typically thought to be important for conservation, did not actually increase species density. However, increasing compactness (low-edge) of patch shape and landscape composition did have the expected effect. Therefore, it is recommended that the composition of the surrounding landscape should be considered simultaneously with planned improvements in local habitat quality.
Jung, Christian; Spreiter, Gregor; Audigé, Laurent; Ferguson, Stephen J; Flury, Matthias
2016-05-01
There is an ongoing debate about the potential of patch augmentation to improve biomechanical stability and healing associated with rotator cuff repair. The biomechanical properties of three different patch-augmented rotator cuff repair techniques were assessed in vitro and compared with a standard repair. Dermal collagen patch augmentation may increase the primary stability and strength of the repaired tendon in vitro, depending on the technique used for patch application. Forty cadaveric sheep shoulders with dissected infraspinatus tendons were randomized into four groups (n = 10/group) for tendon repair using a knotless double-row suture anchor technique. A xenologous dermal extracellular matrix patch was used for augmentation in the three test groups using an "integrated", "cover", or "hybrid" technique. Tendons were preconditioned, cyclically loaded from 10 to 30 N at 1 Hz, and then loaded monotonically to failure. Biomechanical properties and the mode of failure were evaluated. Patch augmentation significantly increased the maximum load at failure by 61 % in the "cover" technique test group (225.8 N) and 51 % in the "hybrid" technique test group (211.4 N) compared with the non-augmented control group (140.2 N) (P ≤ 0.015). For the test group with "integrated" patch augmentation, the load at failure was 28 % lower (101.6 N) compared with the control group (P = 0.043). There was no significant difference in initial and linear stiffness among the four experimental groups. The most common mode of failure was tendon pullout. No anchor dislocation, patch disruption or knot breakage was observed. Additional patch augmentation with a collagen patch influences the biomechanical properties of a rotator cuff repair in a cadaveric sheep model. Primary repair stability can be significantly improved depending on the augmentation technique.
Armstrong, Edward P; Malone, Daniel C; McCarberg, Bill; Panarites, Christopher J; Pham, Sissi V
2011-05-01
The purpose of this study was to compare the cost effectiveness of a new 8% capsaicin patch, compared to the current treatments for postherpetic neuralgia (PHN), including tricyclic antidepressants (TCAs), topical lidocaine patches, duloxetine, gabapentin, and pregabalin. A 1-year Markov model was constructed for PHN with monthly cycles, including dose titration and management of adverse events. The perspective of the analysis was from a payer perspective, managed-care organization. Clinical trials were used to determine the proportion of patients achieving at least a 30% improvement in PHN pain, the efficacy parameter. The outcome was cost per quality-adjusted life-year (QALY); second-order probabilistic sensitivity analyses were conducted. The effectiveness results indicated that 8% capsaicin patch and topical lidocaine patch were significantly more effective than the oral PHN products. TCAs were least costly and significantly less costly than duloxetine, pregabalin, topical lidocaine patch, 8% capsaicin patch, but not gabapentin. The incremental cost-effectiveness ratio for the 8% capsaicin patch overlapped with the topical lidocaine patch and was within the accepted threshold of cost per QALY gained compared to TCAs, duloxetine, gabapentin, and pregablin. The frequency of the 8% capsaicin patch retreatment assumption significantly impacts its cost-effectiveness results. There are several limitations to this analysis. Since no head-to-head studies were identified, this model used inputs from multiple clinical trials. Also, a last observation carried forward process was assumed to have continued for the duration of the model. Additionally, the trials with duloxetine may have over-predicted its efficacy in PHN. Although a 30% improvement in pain is often an endpoint in clinical trials, some patients may require greater or less improvement in pain to be considered a clinical success. The effectiveness results demonstrated that 8% capsaicin and topical lidocaine patches had significantly higher effectiveness rates than the oral agents used to treat PHN. In addition, this cost-effectiveness analysis found that the 8% capsaicin patch was similar to topical lidocaine patch and within an accepted cost per QALY gained threshold compared to the oral products.
Singh, Minerva; Tokola, Timo; Hou, Zhengyang; Notarnicola, Claudia
2017-07-01
Avian species persistence in a forest patch is strongly related to the degree of isolation and size of a forest patch and the vegetation structure within a patch and its matrix are important predictors of bird habitat suitability. A combination of space-borne optical (Landsat), ALOS-PALSAR (radar), and airborne Light Detection and Ranging (LiDAR) data was used for assessing variation in forest structure across forest patches that had undergone different levels of forest degradation in a logged forest-agricultural landscape in Southern Laos. The efficacy of different remote sensing (RS) data sources in distinguishing forest patches that had different seizes, configurations, and vegetation structure was examined. These data were found to be sensitive to the varying levels of degradation of the different patch categories. Additionally, the role of local scale forest structure variables (characterized using the different RS data and patch area) and landscape variables (characterized by distance from different forest patches) in influencing habitat preferences of International Union for Conservation of Nature (IUCN) Red listed birds found in the study area was examined. A machine learning algorithm, MaxEnt, was used in conjunction with these data and field collected geographical locations of the avian species to identify the factors influencing habitat preference of the different bird species and their suitable habitats. Results show that distance from different forest patches played a more important role in influencing habitat suitability for the different avian species than local scale factors related to vegetation structure and health. In addition to distance from forest patches, LiDAR-derived forest structure and Landsat-derived spectral variables were important determinants of avian habitat preference. The models derived using MaxEnt were used to create an overall habitat suitability map (HSM) which mapped the most suitable habitat patches for sustaining all the avian species. This work also provides insight that retention of forest patches, including degraded and isolated forest patches in addition to large contiguous forest patches, can facilitate bird species retention within tropical agricultural landscapes. It also demonstrates the effective use of RS data in distinguishing between forests that have undergone varying levels of degradation and identifying the habitat preferences of different bird species. Practical conservation management planning endeavors can use such data for both landscape scale monitoring and habitat mapping.
An experimental test of the habitat-amount hypothesis for saproxylic beetles in a forested region.
Seibold, Sebastian; Bässler, Claus; Brandl, Roland; Fahrig, Lenore; Förster, Bernhard; Heurich, Marco; Hothorn, Torsten; Scheipl, Fabian; Thorn, Simon; Müller, Jörg
2017-06-01
The habitat-amount hypothesis challenges traditional concepts that explain species richness within habitats, such as the habitat-patch hypothesis, where species number is a function of patch size and patch isolation. It posits that effects of patch size and patch isolation are driven by effects of sample area, and thus that the number of species at a site is basically a function of the total habitat amount surrounding this site. We tested the habitat-amount hypothesis for saproxylic beetles and their habitat of dead wood by using an experiment comprising 190 plots with manipulated patch sizes situated in a forested region with a high variation in habitat amount (i.e., density of dead trees in the surrounding landscape). Although dead wood is a spatio-temporally dynamic habitat, saproxylic insects have life cycles shorter than the time needed for habitat turnover and they closely track their resource. Patch size was manipulated by adding various amounts of downed dead wood to the plots (~800 m³ in total); dead trees in the surrounding landscape (~240 km 2 ) were identified using airborne laser scanning (light detection and ranging). Over 3 yr, 477 saproxylic species (101,416 individuals) were recorded. Considering 20-1,000 m radii around the patches, local landscapes were identified as having a radius of 40-120 m. Both patch size and habitat amount in the local landscapes independently affected species numbers without a significant interaction effect, hence refuting the island effect. Species accumulation curves relative to cumulative patch size were not consistent with either the habitat-patch hypothesis or the habitat-amount hypothesis: several small dead-wood patches held more species than a single large patch with an amount of dead wood equal to the sum of that of the small patches. Our results indicate that conservation of saproxylic beetles in forested regions should primarily focus on increasing the overall amount of dead wood without considering its spatial arrangement. This means dead wood should be added wherever possible including in local landscapes with low or high dead-wood amounts. For species that have disappeared from most forests owing to anthropogenic habitat degradation, this should, however, be complemented by specific conservation measures pursued within their extant distributional ranges. © 2017 by the Ecological Society of America.
Jensen, TS; Høye, K; Fricová, J; Vanelderen, P; Ernault, E; Siciliano, T; Marques, S
2014-01-01
Background Application of the capsaicin 8% patch is associated with treatment-related discomfort. Consequently, pretreatment for 60 min with anaesthetic cream is recommended; however, this may be uncomfortable and time consuming. Methods We conducted a multicentre, randomized (1:1), assessor-blinded study in patients with peripheral neuropathic pain to assess tolerability of the capsaicin patch following topical lidocaine (4%) or oral tramadol (50 mg) pretreatment. The primary endpoint was the proportion of patients tolerating capsaicin patch application (ability to receive ≥90% of a 60-min application). Numeric Pain Rating Scale (NPRS) scores were assessed before, during and after treatment. Results Overall, 122 patients were included (61 per arm). The capsaicin patch was tolerated by 121 patients. Tolerability of the capsaicin patch was similar following pretreatment with lidocaine and tramadol. Following patch application, pain levels increased up to 55 min (change from baseline of 1.3 for lidocaine and 1.4 for tramadol). After patch removal, tramadol-treated patients experienced greater pain relief up to the end of day 1; in the evening, mean changes in NPRS scores from baseline were 0 for lidocaine and −1 for tramadol. Proportions of patients reporting increases of ≥2 NPRS points or >33% from baseline at one or more time point(s) on the day of treatment were similar between arms. Adverse event incidence was comparable between arms. Conclusions Capsaicin 8% patch tolerability was similar in the two arms, with comparable results for most secondary endpoints. Tramadol given 30 min before patch application should be considered as an alternative pretreatment option in patients receiving capsaicin patch treatment. What's already known about this topic? Application of topical capsaicin, a treatment for peripheral neuropathic pain conditions associated with allodynia, can cause painful discomfort. Therefore, a 60-min application of local anaesthetic cream before capsaicin 8% patch treatment was originally recommended. What does this study add? Oral analgesic pretreatment may reduce overall capsaicin patch treatment time and potential unpleasantness associated with applying a topical agent to an allodynic area. Based on LIFT data showing similar tolerability to capsaicin patch regardless of pretreatment method, the European Medicines Agency has issued a type II variation stating: treatment area may be pretreated with a topical anaesthetic or an oral analgesic may be given prior to patch application. PMID:24664539
Wu, Guorong; Kim, Minjeong; Sanroma, Gerard; Wang, Qian; Munsell, Brent C.; Shen, Dinggang
2014-01-01
Multi-atlas patch-based label fusion methods have been successfully used to improve segmentation accuracy in many important medical image analysis applications. In general, to achieve label fusion a single target image is first registered to several atlas images, after registration a label is assigned to each target point in the target image by determining the similarity between the underlying target image patch (centered at the target point) and the aligned image patch in each atlas image. To achieve the highest level of accuracy during the label fusion process it’s critical the chosen patch similarity measurement accurately captures the tissue/shape appearance of the anatomical structure. One major limitation of existing state-of-the-art label fusion methods is that they often apply a fixed size image patch throughout the entire label fusion procedure. Doing so may severely affect the fidelity of the patch similarity measurement, which in turn may not adequately capture complex tissue appearance patterns expressed by the anatomical structure. To address this limitation, we advance state-of-the-art by adding three new label fusion contributions: First, each image patch now characterized by a multi-scale feature representation that encodes both local and semi-local image information. Doing so will increase the accuracy of the patch-based similarity measurement. Second, to limit the possibility of the patch-based similarity measurement being wrongly guided by the presence of multiple anatomical structures in the same image patch, each atlas image patch is further partitioned into a set of label-specific partial image patches according to the existing labels. Since image information has now been semantically divided into different patterns, these new label-specific atlas patches make the label fusion process more specific and flexible. Lastly, in order to correct target points that are mislabeled during label fusion, a hierarchically approach is used to improve the label fusion results. In particular, a coarse-to-fine iterative label fusion approach is used that gradually reduces the patch size. To evaluate the accuracy of our label fusion approach, the proposed method was used to segment the hippocampus in the ADNI dataset and 7.0 tesla MR images, sub-cortical regions in LONI LBPA40 dataset, mid-brain regions in SATA dataset from MICCAI 2013 segmentation challenge, and a set of key internal gray matter structures in IXI dataset. In all experiments, the segmentation results of the proposed hierarchical label fusion method with multi-scale feature representations and label-specific atlas patches are more accurate than several well-known state-of-the-art label fusion methods. PMID:25463474
Cyber Security: Critical Infrastructure Controls Assessment Framework
2011-05-01
the threats to and 3 • Patch and configuration management • Vulnerability and incident t 2 vulnerabilities • Recommendations to reduce 4 managemen 5... Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302. Respondents should be aware that notwithstanding any other...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Purpose P id i t hrov e an overv ew on assessmen
What is Mine is Yours: The Art of Operational Integration
2016-05-10
United States Army School of Advanced Military Studies United States Army Command and General Staff College Fort Leavenworth, Kansas 2016...9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) School of Advanced Military Studies 11. SPONSOR/MONITOR’S...services or national boundaries. Two contrasting World War II case studies , L TG Patch in southern France and L TG Stilwell in Burma, will be used to
Robust Airborne Networking Extensions (RANGE)
2008-02-01
IMUNES [13] project, which provides an entire network stack virtualization and topology control inside a single FreeBSD machine . The emulated topology...Multicast versus broadcast in a manet.” in ADHOC-NOW, 2004, pp. 14–27. [9] J. Mukherjee, R. Atwood , “ Rendezvous point relocation in protocol independent...computer with an Ethernet connection, or a Linux virtual machine on some other (e.g., Windows) operating system, should work. 2.1 Patching the source code
James F. Selgrade; James H. Roberds
2005-01-01
A 4-dimensional system of nonlinear difference equations tracking allele frequencies and population sizes for a two-patch metapopulation model is studied. This system describes intergenerational changes brought about by density-dependent selection within patches and moderated by the effects of migration between patches. To determine conditions which result in similar...
Using an index of habitat patch proximity for landscape design
Eric J. Gustafson; George R. Parker
1994-01-01
A proximity index (PX) inspired by island biogeography theory is described which quantifies the spatial context of a habitat patch in relation to its neighbors. The index distinguishes sparse distributions of small habitat patches from clusters of large patches. An evaluation of the relationship between PX and variation in the spatial characteristics of clusters of...
Functionalized patchy particles using colloidal lenses
NASA Astrophysics Data System (ADS)
Middleton, Christine
2014-03-01
Colloidal assembly had been limited by the isotropic, nonspecific nature of interactions between spherical colloidal particles. By giving particles patches functionalized with single stranded DNA, these interactions can be made both directional and specific. We create patchy particles by adding patches to spherical emulsion droplets using the depletion interaction. First we make polystyrene particles in the shape of contact lenses to be the patches. The lenses are functionalized with single stranded DNA on their convex side. Then we put the lenses on the surface of oil emulsion droplets using the depletion interaction, creating a patch (or multiple patches) on the surface of each emulsion droplet. The emulsion droplets can now interact with each other in a specific, directional way through DNA functionalized patches.
Adult fruit fly attraction to larvae biases experience and mediates social learning.
Durisko, Zachary; Anderson, Blake; Dukas, Reuven
2014-04-01
We investigated whether adult fruit flies (Drosophila melanogaster) use cues of larvae as social information in their food patch choice decisions. Adult male and female fruit flies showed attraction to odours emanating from foraging larvae, and females preferred to lay eggs on food patches occupied by larvae over similar unoccupied patches. Females learned and subsequently preferred to lay eggs at patches with novel flavours previously associated with feeding larvae over patches with novel flavours previously associated with no larvae. However, when we controlled for the duration of exposure to each flavoured patch, females no longer preferred the flavour previously associated with feeding larvae. This suggests that social learning in this context is indirect, as a result of strong social attraction biasing experience.
Tang, Dalin; Yang, Chun; Geva, Tal; Gaudette, Glenn; del Nido, Pedro J.
2011-01-01
Multi-physics right and left ventricle (RV/LV) fluid-structure interaction (FSI) models were introduced to perform mechanical stress analysis and evaluate the effect of patch materials on RV function. The FSI models included three different patch materials (Dacron scaffold, treated pericardium, and contracting myocardium), two-layer construction, fiber orientation, and active anisotropic material properties. The models were constructed based on cardiac magnetic resonance (CMR) images acquired from a patient with severe RV dilatation and solved by ADINA. Our results indicate that the patch model with contracting myocardium leads to decreased stress level in the patch area, improved RV function and patch area contractility. PMID:21765559
Effect of growth hormone, hyperbaric oxygen and combined therapy on the gastric serosa
Adas, Gokhan; Adas, Mine; Arikan, Soykan; Sarvan, Ahu Kemik; Toklu, Akin Savas; Mert, Selva; Barut, Gul; Kamali, Sedat; Koc, Bora; Tutal, Firat
2013-01-01
AIM: To investigate the role of growth hormone (GH), hyperbaric oxygen therapy (HBOT) and combined therapy on the intestinal neomucosa formation of the gastric serosa. METHODS: Forty-eight male Wistar-albino rats, weighing 250-280 g, were used in this study. The rats were divided into four groups (n = 12): Group 1, control, gastric serosal patch; Group 2, gastric serosal patch + GH; Group 3, gastric serosal patch + HBOT; and Group 4, gastric serosal patch + GH + HBOT. Abdominal access was achieved through a midline incision, and after the 1-cm-long defect was created in the jejunum, a 1 cm × 1 cm patch of the gastric corpus was anastomosed to the jejunal defect. Venous blood samples were taken to determine the insulin-like growth factor 1 (IGF-1) and insulin-like growth factor binding protein 3 (IGFBP-3) basal levels. HBOT was performed in Groups 3 and 4. In Groups 2 and 4, human GH was given subcutaneously at a dose of 2 mg per kg/d for 28 d, beginning on the operation day. All animals were sacrificed 60 d after surgery. The jejunal segment and the gastric anastomotic area were excised for histological examination. The inflammatory process, granulation, collagen deposition and fibroblast activity at the neomucosa formation were studied and scored. Additionally, the villus density, villus height, and crypt depth were counted and recorded. The measurements of villus height and crypt depth were calculated with an ocular micrometer. New vessel growth was determined by calculatingeach new vessel in a 1 mm2 area. RESULTS: In the histological comparison of groups, no significant differences were observed between the control group and Groups 2 and 3 with respect to epithelialization, granulation, fibroblastic activity and the inflammatory process, but significant differences were present between the control group and all others groups (Groups 2-4) with respect to angiogenesis (P < 0.01) and collagen deposition (P < 0.05, P < 0.01). Significant differences between the control group and Group 4 were also observed with respect to epithelialization and fibroblastic activity (P < 0.01 and P < 0.05, respectively). There were significant differences in villus density in all of groups compared with the control group (P < 0.05). Crypt depth was significantly greater in Group 4 than in the control group (P < 0.05), but no other groups had deeper crypts. However, villus height was significantly longer in Groups 2 and 4 than in the control group (P < 0.05). The comparison of groups revealed, significant difference between control group and Groups 2 and 4) with respect to the levels of IGF-1 and IGFBP-3 (P < 0.01) 3 wk after the operation. CONCLUSION: HBOT or GH and combined therapy augmented on neomucosal formation. The use of combined therapy produced a synergistic effect on the histological, morphological and functional parameters. PMID:23704823
Pedreira, Denise A L; Zanon, Nelci; de Sá, Renato A M; Acacio, Gregório L; Ogeda, Edilson; Belem, Teresa M L O U; Chmait, Ramen H; Kontopoulos, Eftichia; Quintero, Ruben A
2014-11-01
To report our preliminary clinical experience in the antenatal correction of open spina bifida (OSB) using a fetoscopic approach and a simplified closure technique. Four fetuses with lumbar-sacral defects were operated in utero from 25 to 27 weeks. Surgeries were performed percutaneously under general anesthesia using three trocars and partial carbon dioxide insufflation. After dissection of the neural placode, the surrounding skin was closed over a cellulose patch using a single continuous stitch. Surgical closure was successful in three of the four cases. All successful cases showed improvement of the hindbrain herniation and no neonatal neurosurgical repair was required in two cases. Delivery occurred between 31 and 33 weeks, and no fetal or neonatal deaths occurred. Ventriculoperitoneal shunting was not needed in two out of the 3 successful cases. Our preliminary experience suggests that definitive fetoscopic repair of OSB is feasible using our innovative surgical technique. A phase I trial for the fetoscopic correction of OSB with this technique is currently being conducted.
NASA Astrophysics Data System (ADS)
Zou, Z.; Scott, M. A.; Borden, M. J.; Thomas, D. C.; Dornisch, W.; Brivadis, E.
2018-05-01
In this paper we develop the isogeometric B\\'ezier dual mortar method. It is based on B\\'ezier extraction and projection and is applicable to any spline space which can be represented in B\\'ezier form (i.e., NURBS, T-splines, LR-splines, etc.). The approach weakly enforces the continuity of the solution at patch interfaces and the error can be adaptively controlled by leveraging the refineability of the underlying dual spline basis without introducing any additional degrees of freedom. We also develop weakly continuous geometry as a particular application of isogeometric B\\'ezier dual mortaring. Weakly continuous geometry is a geometry description where the weak continuity constraints are built into properly modified B\\'ezier extraction operators. As a result, multi-patch models can be processed in a solver directly without having to employ a mortaring solution strategy. We demonstrate the utility of the approach on several challenging benchmark problems. Keywords: Mortar methods, Isogeometric analysis, B\\'ezier extraction, B\\'ezier projection
Hierarchical surface code for network quantum computing with modules of arbitrary size
NASA Astrophysics Data System (ADS)
Li, Ying; Benjamin, Simon C.
2016-10-01
The network paradigm for quantum computing involves interconnecting many modules to form a scalable machine. Typically it is assumed that the links between modules are prone to noise while operations within modules have a significantly higher fidelity. To optimize fault tolerance in such architectures we introduce a hierarchical generalization of the surface code: a small "patch" of the code exists within each module and constitutes a single effective qubit of the logic-level surface code. Errors primarily occur in a two-dimensional subspace, i.e., patch perimeters extruded over time, and the resulting noise threshold for intermodule links can exceed ˜10 % even in the absence of purification. Increasing the number of qubits within each module decreases the number of qubits necessary for encoding a logical qubit. But this advantage is relatively modest, and broadly speaking, a "fine-grained" network of small modules containing only about eight qubits is competitive in total qubit count versus a "course" network with modules containing many hundreds of qubits.
One-channel Cell-attached Patch-clamp Recording
Maki, Bruce A.; Cummings, Kirstie A.; Paganelli, Meaghan A.; Murthy, Swetha E.; Popescu, Gabriela K.
2014-01-01
Ion channel proteins are universal devices for fast communication across biological membranes. The temporal signature of the ionic flux they generate depends on properties intrinsic to each channel protein as well as the mechanism by which it is generated and controlled and represents an important area of current research. Information about the operational dynamics of ion channel proteins can be obtained by observing long stretches of current produced by a single molecule. Described here is a protocol for obtaining one-channel cell-attached patch-clamp current recordings for a ligand gated ion channel, the NMDA receptor, expressed heterologously in HEK293 cells or natively in cortical neurons. Also provided are instructions on how to adapt the method to other ion channels of interest by presenting the example of the mechano-sensitive channel PIEZO1. This method can provide data regarding the channel’s conductance properties and the temporal sequence of open-closed conformations that make up the channel’s activation mechanism, thus helping to understand their functions in health and disease. PMID:24961614
UHF Microstrip Antenna Array for Synthetic- Aperture Radar
NASA Technical Reports Server (NTRS)
Thomas, Robert F.; Huang, John
2003-01-01
An ultra-high-frequency microstrippatch antenna has been built for use in airborne synthetic-aperture radar (SAR). The antenna design satisfies requirements specific to the GeoSAR program, which is dedicated to the development of a terrain-mapping SAR system that can provide information on geology, seismicity, vegetation, and other terrain-related topics. One of the requirements is for ultra-wide-band performance: the antenna must be capable of operating with dual linear polarization in the frequency range of 350 plus or minus 80 MHz, with a peak gain of 10 dB at the middle frequency of 350 MHz and a gain of at least 8 dB at the upper and lower ends (270 and 430 MHz) of the band. Another requirement is compactness: the antenna must fit in the wingtip pod of a Gulfstream II airplane. The antenna includes a linear array of microstrip-patch radiating elements supported over square cavities. Each patch is square (except for small corner cuts) and has a small square hole at its center.
Luo, Xiongbiao; Jayarathne, Uditha L; McLeod, A Jonathan; Mori, Kensaku
2014-01-01
Endoscopic navigation generally integrates different modalities of sensory information in order to continuously locate an endoscope relative to suspicious tissues in the body during interventions. Current electromagnetic tracking techniques for endoscopic navigation have limited accuracy due to tissue deformation and magnetic field distortion. To avoid these limitations and improve the endoscopic localization accuracy, this paper proposes a new endoscopic navigation framework that uses an optical mouse sensor to measure the endoscope movements along its viewing direction. We then enhance the differential evolution algorithm by modifying its mutation operation. Based on the enhanced differential evolution method, these movement measurements and image structural patches in endoscopic videos are fused to accurately determine the endoscope position. An evaluation on a dynamic phantom demonstrated that our method provides a more accurate navigation framework. Compared to state-of-the-art methods, it improved the navigation accuracy from 2.4 to 1.6 mm and reduced the processing time from 2.8 to 0.9 seconds.
Expedition 52 Crew Patch-042517
2016-11-17
ISS052-s-001 (01/27/2016) --- Orbiting the Earth continuously since 1998, the International Space Station (ISS) is one of our greatest engineering achievements. It is depicted in gold, symbolic of constancy and excellence. Flying directly toward a sunrise represents the ISS’s contributions to a bright future. That sunrise and the Earth beneath ituses blue, white, red, and green, the combined national colors of Italy, Russia, and the United States, symbolizing the crew’s cohesiveness. Crewmember names are in blue symbolizing devotion and loyalty. The white border represents sunlight unscattered by the Earth’s atmosphere. Symbolic of new Russian and U.S. spacecraft that will further human exploration, the patch is shaped as a capsule. The number 52 is drawn as a path eventually leading to Mars. Finally, the stars symbolize the values of leadership, trust, teamwork, and excellence lived by mission control teams throughout the history of human space programs, as well as their global vigilance in operating the ISS.
Monro, Donald M; Rakshit, Soumyadip; Zhang, Dexin
2007-04-01
This paper presents a novel iris coding method based on differences of discrete cosine transform (DCT) coefficients of overlapped angular patches from normalized iris images. The feature extraction capabilities of the DCT are optimized on the two largest publicly available iris image data sets, 2,156 images of 308 eyes from the CASIA database and 2,955 images of 150 eyes from the Bath database. On this data, we achieve 100 percent Correct Recognition Rate (CRR) and perfect Receiver-Operating Characteristic (ROC) Curves with no registered false accepts or rejects. Individual feature bit and patch position parameters are optimized for matching through a product-of-sum approach to Hamming distance calculation. For verification, a variable threshold is applied to the distance metric and the False Acceptance Rate (FAR) and False Rejection Rate (FRR) are recorded. A new worst-case metric is proposed for predicting practical system performance in the absence of matching failures, and the worst case theoretical Equal Error Rate (EER) is predicted to be as low as 2.59 x 10(-4) on the available data sets.
A comparison of the impact of 'seagrass-friendly' boat mooring systems on Posidonia australis.
Demers, Marie-Claire A; Davis, Andrew R; Knott, Nathan A
2013-02-01
Permanent boat moorings have contributed to the decline of seagrasses worldwide, prompting the development of 'seagrass-friendly' moorings. We contrasted seagrass cover and density (predominantly Posidonia australis) in the vicinity of three mooring types and nearby reference areas lacking moorings in Jervis Bay, Australia. We examined two types of 'seagrass-friendly' mooring and a conventional 'swing' mooring. 'Swing' moorings produced significant seagrass scour, denuding patches of ~9 m radius. Seagrass-friendly 'cyclone' moorings produced extensive denuded patches (average radius of ~18 m). Seagrass-friendly 'screw' moorings, conversely, had similar seagrass cover to nearby reference areas. Our findings reinforce previous work highlighting the negative effects of 'swing' and 'cyclone' moorings. In contrast, the previously unstudied 'screw' moorings were highly effective. We conclude that regular maintenance of moorings and the monitoring of surrounding seagrass are required to ensure that 'seagrass-friendly' moorings are operating effectively. This is important, as following damage Posidonia will take many decades to recover. Copyright © 2012 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Moiroux, Joffrey; Abram, Paul K.; Louâpre, Philippe; Barrette, Maryse; Brodeur, Jacques; Boivin, Guy
2016-04-01
Patch time allocation has received much attention in the context of optimal foraging theory, including the effect of environmental variables. We investigated the direct role of temperature on patch time allocation by parasitoids through physiological and behavioural mechanisms and its indirect role via changes in sex allocation and behavioural defences of the hosts. We compared the influence of foraging temperature on patch residence time between an egg parasitoid, Trichogramma euproctidis, and an aphid parasitoid, Aphidius ervi. The latter attacks hosts that are able to actively defend themselves, and may thus indirectly influence patch time allocation of the parasitoid. Patch residence time decreased with an increase in temperature in both species. The increased activity levels with warming, as evidenced by the increase in walking speed, partially explained these variations, but other mechanisms were involved. In T. euproctidis, the ability to externally discriminate parasitised hosts decreased at low temperature, resulting in a longer patch residence time. Changes in sex allocation with temperature did not explain changes in patch time allocation in this species. For A. ervi, we observed that aphids frequently escaped at intermediate temperature and defended themselves aggressively at high temperature, but displayed few defence mechanisms at low temperature. These defensive behaviours resulted in a decreased patch residence time for the parasitoid and partly explained the fact that A. ervi remained for a shorter time at the intermediate and high temperatures than at the lowest temperature. Our results suggest that global warming may affect host-parasitoid interactions through complex mechanisms including both direct and indirect effects on parasitoid patch time allocation.
Danker, Timm; Braun, Franziska; Silbernagl, Nikole; Guenther, Elke
2016-03-01
Manual patch clamp, the gold standard of electrophysiology, represents a powerful and versatile toolbox to stimulate, modulate, and record ion channel activity from membrane fragments and whole cells. The electrophysiological readout can be combined with fluorescent or optogenetic methods and allows for ultrafast solution exchanges using specialized microfluidic tools. A hallmark of manual patch clamp is the intentional selection of individual cells for recording, often an essential prerequisite to generate meaningful data. So far, available automation solutions rely on random cell usage in the closed environment of a chip and thus sacrifice much of this versatility by design. To parallelize and automate the traditional patch clamp technique while perpetuating the full versatility of the method, we developed an approach to automation, which is based on active cell handling and targeted electrode placement rather than on random processes. This is achieved through an automated pipette positioning system, which guides the tips of recording pipettes with micrometer precision to a microfluidic cell handling device. Using a patch pipette array mounted on a conventional micromanipulator, our automated patch clamp process mimics the original manual patch clamp as closely as possible, yet achieving a configuration where recordings are obtained from many patch electrodes in parallel. In addition, our implementation is extensible by design to allow the easy integration of specialized equipment such as ultrafast compound application tools. The resulting system offers fully automated patch clamp on purposely selected cells and combines high-quality gigaseal recordings with solution switching in the millisecond timescale.
Effective Connectivity Reveals Largely Independent Parallel Networks of Face and Body Patches.
Premereur, Elsie; Taubert, Jessica; Janssen, Peter; Vogels, Rufin; Vanduffel, Wim
2016-12-19
The primate brain processes objects in the ventral visual pathway. One object category, faces, is processed in a hierarchical network of interconnected areas along this pathway. It remains unknown whether such an interconnected network is specific for faces or whether there are similar networks for other object classes. For example, the primate inferotemporal cortex also contains a set of body-selective patches, adjacent to the face-selective patches, but it is not known whether these body-selective patches form a similar discretely connected network or whether cross-talk exists between the face- and body-processing systems. To address these questions, we combined fMRI with electrical microstimulation to determine the effective connectivity of fMRI-defined face and body patches. We found that microstimulation of face patches caused increased fMRI activation throughout the face-processing system; microstimulation of the body patches gave similar results restricted to the body-processing system. Critically, our results revealed largely segregated connectivity patterns for the body and face patches. These results suggest that face and body patches form two interconnected hierarchical networks that are largely separated within the monkey inferotemporal cortex. Only a restricted number of voxels were activated by stimulation of both the body and face patches. The latter regions may be important for the integration of face and body information. Our findings are not only essential to advance our understanding of the neural circuits that enable social cognition, but they also provide further insights into the organizing principles of the inferotemporal cortex. Copyright © 2016 Elsevier Ltd. All rights reserved.
Pita, Ricardo; Mira, António; Beja, Pedro
2013-01-01
The ability of patchy populations to persist in human-dominated landscapes is often assessed using focal patch approaches, in which the local occurrence or abundance of a species is related to the properties of individual patches and the surrounding landscape context. However, useful additional insights could probably be gained through broader, mosaic-level approaches, whereby whole land mosaics with contrasting patch-network and matrix characteristics are the units of investigation. In this study we addressed this issue, analysing how the southern water vole (Arvicola sapidus) responds to variables describing patch-network and matrix properties within replicated Mediterranean farmland mosaics, across a gradient of agricultural intensification. Patch-network characteristics had a dominant effect, with the total amount of habitat positively influencing both the occurrence of water voles and the proportion of area occupied in land mosaics. The proportions of patches and area occupied by the species were positively influenced by mean patch size, and negatively so by patch isolation. Matrix effects were weak, although there was a tendency for a higher proportion of occupied patches in more intensive, irrigated agricultural landscapes, particularly during the dry season. In terms of conservation, results suggest that water voles may be able to cope well with, or even be favoured by, the on-going expansion of irrigated agriculture in Mediterranean dry-lands, provided that a number of patches of wet herbaceous vegetation are maintained within the farmland mosaic. Overall, our study suggests that the mosaic-level approach may provide a useful framework to understand the responses of patchy populations to land use change.
Landscape characteristics of disturbed shrubsteppe habitats in southwestern Idaho (USA)
Knick, Steven T.; Rotenberry, J.T.
1997-01-01
We compared 5 zones in shrubsteppe habitats of southwestern Idaho to determine the effect of differing disturbance combinations on landscapes that once shared historically similar disturbance regimes. The primary consequence of agriculture, wildfires, and extensive fires ignited by the military during training activities was loss of native shrubs from the landscape. Agriculture created large square blocks on the landscape, and the landscape contained fewer small patches and more large shrub patches than non-agricultural areas. In contrast, fires left a more fragmented landscape. Repeated fires did not change the distribution of patch sizes, but decreased the total area of remaining shrublands and increased the distance between remaining shrub patches that provide seed sources. Military training with tracked vehicles was associated with a landscape characterized by small, closely spaced, shrub patches. Our results support the general model hypothesized for conversion of shrublands to annual grasslands by disturbance. Larger shrub patches in our region, historically resistant to fire spread and large-scale fires because of a perennial bunchgrass understory, were more fragmented than small patches. Presence of cheatgrass (Bromus tectorum), an exotic annual, was positively related to landscape patchiness and negatively related to number of shrub cells. Thus, cheatgrass dominance can contribute to further fragmentation and loss of the shrub patch by facilitating spread of subsequent fires, carried by continuous fuels, through the patch. The synergistic processes of fragmentation of shrub patches by disturbance, invasion and subsequent dominance by exotic annuals, and fire are converting shrubsteppe in southwestern Idaho to a new state dominated by exotic annual grasslands and high fire frequencies.
Pita, Ricardo; Lambin, Xavier; Mira, António; Beja, Pedro
2016-09-01
According to ecological theory, the coexistence of competitors in patchy environments may be facilitated by hierarchical spatial segregation along axes of environmental variation, but empirical evidence is limited. Cabrera and water voles show a metapopulation-like structure in Mediterranean farmland, where they are known to segregate along space, habitat, and time axes within habitat patches. Here, we assess whether segregation also occurs among and within landscapes, and how this is influenced by patch-network and matrix composition. We surveyed 75 landscapes, each covering 78 ha, where we mapped all habitat patches potentially suitable for Cabrera and water voles, and the area effectively occupied by each species (extent of occupancy). The relatively large water vole tended to be the sole occupant of landscapes with high habitat amount but relatively low patch density (i.e., with a few large patches), and with a predominantly agricultural matrix, whereas landscapes with high patch density (i.e., many small patches) and low agricultural cover, tended to be occupied exclusively by the small Cabrera vole. The two species tended to co-occur in landscapes with intermediate patch-network and matrix characteristics, though their extents of occurrence were negatively correlated after controlling for environmental effects. In combination with our previous studies on the Cabrera-water vole system, these findings illustrated empirically the occurrence of hierarchical spatial segregation, ranging from within-patches to among-landscapes. Overall, our study suggests that recognizing the hierarchical nature of spatial segregation patterns and their major environmental drivers should enhance our understanding of species coexistence in patchy environments.
A procedure of landscape services assessment based on mosaics of patches and boundaries.
Martín de Agar, Pilar; Ortega, Marta; de Pablo, Carlos L
2016-09-15
We develop a procedure for assessing the environmental value of landscape mosaics that simultaneously considers the values of land use patches and the values of the boundaries between them. These boundaries indicate the ecological interactions between the patches. A landscape mosaic is defined as a set of patches and the boundaries between them and corresponds to a spatial pattern of ecological interactions. The procedure is performed in two steps: (i) an environmental assessment of land use patches by means of a function that integrates values based on the goods and services the patches provide, and (ii) an environmental valuation of mosaics using a function that integrates the environmental values of their patches and the types and frequencies of the boundaries between them. This procedure allows us to measure how changes in land uses or in their spatial arrangement cause variations in the environmental value of landscape mosaics and therefore in that of the whole landscape. The procedure was tested in the Sierra Norte of Madrid (central Spain). The results show that the environmental values of the landscape depend not only on the land use patches but also on the values associated with the pattern of the boundaries within the mosaics. The results also highlight the importance of the boundaries between land use patches as determinants of the goods and services provided by the landscape. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bust economics: foragers choose high quality habitats in lean times
Dickman, Christopher R.
2016-01-01
In environments where food resources are spatially variable and temporarily impoverished, consumers that encounter habitat patches with different food density should focus their foraging initially where food density is highest before they move to patches where food density is lower. Increasing missed opportunity costs should drive individuals progressively to patches with lower food density as resources in the initially high food density patches deplete. To test these expectations, we assessed the foraging decisions of two species of dasyurid marsupials (dunnarts: Sminthopsis hirtipes and S. youngsoni) during a deep drought, or bust period, in the Simpson Desert of central Australia. Dunnarts were allowed access to three patches containing different food densities using an interview chamber experiment. Both species exhibited clear preference for the high density over the lower food density patches as measured in total harvested resources. Similarly, when measuring the proportion of resources harvested within the patches, we observed a marginal preference for patches with initially high densities. Models analyzing behavioral choices at the population level found no differences in behavior between the two species, but models analyzing choices at the individual level uncovered some variation. We conclude that dunnarts can distinguish between habitat patches with different densities of food and preferentially exploit the most valuable. As our observations were made during bust conditions, experiments should be repeated during boom times to assess the foraging economics of dunnarts when environmental resources are high. PMID:26839751
Guangming, Gan; Tao, Zhao; Chao, Li; Moyan, Zhao
2017-01-01
The black-spotted frog (Pelophylax nigromaculata) and Asiatic toad (Bufo gargarizans), two relatively distantly related species, live in different habitats with different adaptive dark patches. To explain the formation of dark patches, the distribution patterns of melanin granules were examined with light microscopy and transmission electron microscopy. Melanin granules were produced and gathered into the "cap" structures on top of the nuclei in most epidermal cells. The "cap" structures may play a role in forming the dorsal dark patches coupled with three-layer melanophores, which can give rise to three layers of interconnected melanin networks in the dorsal dermis in P. nigromaculata. Epidermal melanocytes are rare and do not have a definitive role in forming dorsal dark patches in either P. nigromaculata or B. gargarizans. In B. gargarizans, the dermal melanophores only give rise to a single-layered melanin network, which hardly results in dark patches in the dorsal skin. However, the dermal melanophores migrate twice and form into pseudostratified networks, leading to dark patch formation in the ventral skin in B. gargarizans. The melanin granules precisely coregulate dark patches in the dermis and/or epidermis in P. nigromaculata and B. gargarizans. The dark patch formation depends on melanin granules in the epidermis or/and dermis in P. nigromaculata and B. gargarizans.
Adolescents' experiences using the contraceptive patch versus pills.
Sucato, Gina S; Land, Stephanie R; Murray, Pamela J; Cecchini, Reena; Gold, Melanie A
2011-08-01
To compare use of the weekly transdermal contraceptive patch (patch) with daily combined hormonal contraceptive pills (pills) in adolescents. Prospective longitudinal study of adolescents' self-selected (non-randomized) use of the patch or pills. Urban, university hospital-affiliated, adolescent outpatient clinic. 13-22-year-old female adolescents seeking hormonal contraception, 40 who chose the patch and 40 who chose pills. Data were collected via self-report on paper questionnaires at three-cycle intervals for a total of up to nine cycles. Method continuation, perfect use, method satisfaction, quality of life, and side effects, including menstrual changes and perceived mood changes. After nine cycles, 38% of patch users and 60% of pill users were still using the method they had chosen at enrollment. There were no significant differences between the groups in self-reported perfect use. No differences were found in quality of life or side effects. Both patch and pill users noted menses became lighter and more predictable and reported decreased depression prior to their menses; only the pill group reported improvement in premenstrual anger. Method satisfaction was similar in both groups except patch users were more likely to report that their contraceptive method improved normal daily activities. Despite apparent advantages of the patch over the pill, adolescents using both methods continue to face challenges achieving perfect and sustained contraceptive use. 2011 North American Society for Pediatric and Adolescent Gynecology. Published by Elsevier Inc. All rights reserved.
Takahashi, Kei; Toyota, Taro
2015-01-01
The cytosol of amoeba cells controls the membrane deformation during their motion in vivo. To investigate such ability of the cytosol of amoeba cell, Dictyostelium discoideum (Dictyostelium), in vitro, we used lipids extracted from Dictyostelium and commercially available phospholipids, and prepared substrate-supported lipid membrane patches on the micrometer scale by spin coating. We found that the spin coater holder, which has pores (pore size = 3.1 mm) of negative pressure to hold the cover glass induced the concave surface of the cover glass. The membrane lipid patches were formed at each position in the vicinity of the holder pores and their sizes were in the range of 2.7 to 3.2 × 10(4) μm(2). After addition of the cytosol extracted from Dictyostelium to the lipid membrane patches, through time-lapse observation with a confocal laser scanning fluorescence microscope, we observed an autonomous buckling of the Dictyostelium lipid patches and localized behaviours of proteins found within. The current method serves as the novel technique for the preparation of film patches in which the positions of patches are controlled by the holder pores without fabricating, modifying, and arranging the chemical properties of the solution components of lipids. The findings imply that lipid-binding proteins in the cytosol were adsorbed and accumulated within the Dictyostelium lipid patches, inducing the transformation of the cell-sized patch.
Birth control - slow release methods
Contraception - slow-release hormonal methods; Progestin implants; Progestin injections; Skin patch; Vaginal ring ... might want to consider a different birth control method. SKIN PATCH The skin patch is placed on ...
Landscape and patch-level factors influence bird communities in an urbanized tropical island
Marcela Suarez-Rubio; John R. Thomlinson
2009-01-01
As human population continues to increase and intensification of human land use escalates, it is important to address the role of urban forest patches in supporting bird communities. We related bird species richness and community assemblage to landscape- and patch- level factors in 40 forest patches in the densely populated metropolitan area of San Juan, Puerto Rico....
Immunosuppressive and Anti-Inflammatory Effects of Nicotine Administered by Patch in an Animal Model
Kalra, Roma; Singh, Shashi P.; Pena-Philippides, Juan C.; Langley, Raymond J.; Razani-Boroujerdi, Seddigheh; Sopori, Mohan L.
2004-01-01
To study the immunological effects of nicotine, there are several rodent models for chronic nicotine administration. These models include subcutaneously implanted miniosmotic pumps, nicotine-spiked drinking water, and self-administration via jugular cannulae. Administration of nicotine via these routes affects the immune system. Smokers frequently use nicotine patches to quit smoking, and the immunological effects of nicotine patches are largely unknown. To determine whether the nicotine patch affects the immune system, nicotine patches were affixed daily onto the backs of Lewis rats for 3 to 4 weeks. The patches efficiently raised the levels of nicotine and cotinine in serum and strongly inhibited the antibody-forming cell response of spleen cells to sheep red blood cells. The nicotine patch also suppressed the concanavalin A-induced T-cell proliferation and mobilization of intracellular Ca2+ by spleen cells, as well as the fever response of animals to subcutaneous administration of turpentine. Moreover, immunosuppression was associated with chronic activation of protein tyrosine kinase and phospholipase C-γ1 activities. Thus, in this animal model of nicotine administration, the nicotine patch efficiently raises the levels of nicotine and cotinine in serum and impairs both the immune and inflammatory responses. PMID:15138183
Use of rivastigmine transdermal patch in the treatment of Alzheimer's disease.
Winblad, Bengt; Machado, João Carlos
2008-12-01
Cholinesterase inhibitors such as rivastigmine and donepezil exhibit a dose-response relationship, with higher doses of the drugs demonstrating greater efficacy. Transdermal patches provide smooth continuous drug delivery, with the potential to offer efficacious levels of drug exposure while avoiding the peaks and troughs associated with side effects. As a small, lipophilic and hydrophilic molecule, rivastigmine (C14H22N2O2) is chemically well-suited to transdermal delivery. The technology underlying the rivastigmine patch allows it to be discreetly small and thin. The target dose 9.5 mg/24 h rivastigmine patch has a diameter of just 3.5 cm and a surface area of 10 cm2. A large randomized controlled trial has demonstrated that the target dose 9.5 mg/24 h rivastigmine patch provided similar efficacy to the highest rivastigmine capsule doses, yet with three times fewer reports of nausea and vomiting. Thus, the rivastigmine patch enables quick and easy access to high dose efficacy. The skin tolerability profile is good, and the patch has demonstrated excellent adhesion. The apparent success of rivastigmine patch, in terms of clinical utility and patient acceptability, suggests that it may mark the next generation of dementia treatment.
Wei, Zewen; Huang, Yuanyu; Zhao, Deyao; Hu, Zhiyuan; Li, Zhihong; Liang, Zicai
2015-01-05
Delivery of nucleic acids into animal tissues by electroporation is an appealing approach for various types of gene therapy, but efficiency of existing methodsis not satisfactory. Here we present the validation of novel electroporation patch (ep-Patch) for efficient delivery of DNA and siRNA into mouse tissues. Using micromachining technology, closely spaced gold electrodes were made on the pliable parylene substrate to form a patch-like electroporation metrics. It enabled large coverage of the target tissues and close surface contact between the tissues and electrodes, thus providing a uniform electric field to deliver nucleic acids into tissues, even beneath intact skin. Using this ep-Patch for efficiently delivery of both DNA and siRNA, non-invasive electroporation of healthy mouse muscle tissue was successfully achieved. Delivery of these nucleic acids was performed to intact tumors with satisfactory results. Silencing of tumor genes using the ep-Patch was also demonstrated on mice. This pliable electroporation patch method constitutes a novel way of in vivo delivery of siRNA and DNA to certain tissues or organs to circumvent the disadvantages of existing methodologies for in vivo delivery of nucleic acid molecules.
Development of a self-stressing NiTiNb shape memory alloy (SMA)/fiber reinforced polymer (FRP) patch
NASA Astrophysics Data System (ADS)
El-Tahan, M.; Dawood, M.; Song, G.
2015-06-01
The objective of this research is to develop a self-stressing patch using a combination of shape memory alloys (SMAs) and fiber reinforced polymer (FRP) composites. Prestressed carbon FRP patches are emerging as a promising alternative to traditional methods to repair cracked steel structures and civil infrastructure. However, prestressing these patches typically requires heavy and complex fixtures, which is impractical in many applications. This paper presents a new approach in which the prestressing force is applied by restraining the shape memory effect of NiTiNb SMA wires. The wires are subsequently embedded in an FRP overlay patch. This method overcomes the practical challenges associated with conventional prestressing. This paper presents the conceptual development of the self-stressing patch with the support of experimental observations. The bond between the SMA wires and the FRP is evaluated using pull-out tests. The paper concludes with an experimental study that evaluates the patch response during activation subsequent monotonic tensile loading. The results demonstrate that the self-stressing patch with NiTiNb SMA is capable of generating a significant prestressing force with minimal tool and labor requirements.
Nyquist, B; Tyson, R; Larsen, K
2007-05-01
In this paper, we present a model for source-sink population dynamics where the locations of source and sink habitats change over time. We do this in the context of the population dynamics of the North American red squirrel, Tamiasciurus hudsonicus, within a forest environment subject to harvesting and regrowth. Harvested patches of forest are initially sinks, then eventually become source habitat again as the forest regrows. At the same time, each harvested patch is gradually recolonized by squirrels from other forest patches. We are interested in the interaction of forest harvesting dynamics with squirrel population dynamics. This depends on the harvesting schedule, and on the choices squirrels make when deciding whether to settle in a mature forest patch or in a recently harvested patch. We find that the time it takes for a second-growth forest patch to be recolonized at the mature forest level is longer than the time required for the habitat quality to be restored to the mature forest level. We also notice that recolonization pressure decreases squirrel populations in neighbouring patches. The connectivity between forest patches and the cutting schedule used also affect the time course of recolonization and steady-state population levels.
Inhibition effects of a negative electret 5-FU patch on the growth of a hypertrophic scar
NASA Astrophysics Data System (ADS)
Wang, YUAN; Lili, XU; Ping, HUANG; Xiaoqiang, AN; Lili, CUI; Jian, JIANG
2018-05-01
In this study, the hypertrophic scar (HS) model in rats was established. 5-fluorouracil (5-FU) patch, ‑1000 V and ‑2000 V polypropylene (PP) electret 5-FU patches were prepared and applied onto the wound. The in vitro permeation experiment was performed using the Franz diffusion cell system to determine the permeation cumulative amount and retention amount of 5-FU through/in scar skin. The inhibition effect of negative electret on growth of HS was studied by hematoxylin-eosin (HE) staining, Masson staining and the immunohistologicall methods. The permeation study indicated that a negative electret could enhance the permeation and retention of 5-FU through and in scar skin respectively. HE staining and Masson staining indicated a better effect for ‑1000 V and ‑2000 V electret 5-FU patches on HS inhibition after 28 d post-wounding compared with 5-FU patch. The immunohistological study showed much more reduced expressions of collegan type I, collegan type III, TGF-β1 and HSP47 in scar tissue after application of negative electret 5-FU patches than those of 5-FU patch. A negative electret 5-FU patch may be advantageous for HS treatment.
Large-scale binding ligand prediction by improved patch-based method Patch-Surfer2.0
Zhu, Xiaolei; Xiong, Yi; Kihara, Daisuke
2015-01-01
Motivation: Ligand binding is a key aspect of the function of many proteins. Thus, binding ligand prediction provides important insight in understanding the biological function of proteins. Binding ligand prediction is also useful for drug design and examining potential drug side effects. Results: We present a computational method named Patch-Surfer2.0, which predicts binding ligands for a protein pocket. By representing and comparing pockets at the level of small local surface patches that characterize physicochemical properties of the local regions, the method can identify binding pockets of the same ligand even if they do not share globally similar shapes. Properties of local patches are represented by an efficient mathematical representation, 3D Zernike Descriptor. Patch-Surfer2.0 has significant technical improvements over our previous prototype, which includes a new feature that captures approximate patch position with a geodesic distance histogram. Moreover, we constructed a large comprehensive database of ligand binding pockets that will be searched against by a query. The benchmark shows better performance of Patch-Surfer2.0 over existing methods. Availability and implementation: http://kiharalab.org/patchsurfer2.0/ Contact: dkihara@purdue.edu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:25359888
Clinchy, Michael; Haydon, Daniel T; Smith, Andrew T
2002-04-01
Patch occupancy surveys are commonly used to parameterize metapopulation models. If isolation predicts patch occupancy, this is generally attributed to a balance between distance-dependent recolonization and spatially independent extinctions. We investigated whether similar patterns could also be generated by a process of spatially correlated extinctions following a unique colonization event (analogous to nonequilibrium processes in island biogeography). We simulated effects of spatially correlated extinctions on patterns of patch occupancy among pikas (Ochotona princeps) at Bodie, California, using randomly located extinction disks to represent the likely effects of predation. Our simulations produced similar patterns to those cited as evidence of balanced metapopulation dynamics. Simulations using a variety of disk sizes and patch configurations confirmed that our results are potentially applicable to a broad range of species and sites. Analyses of the observed patterns of patch occupancy at Bodie revealed little evidence of rescue effects and strong evidence that most recolonizations are ephemeral in nature. Persistence will be overestimated if static or declining patterns of patch occupancy are mistakenly attributed to dynamically stable metapopulation processes. Consequently, simple patch occupancy surveys should not be considered as substitutes for detailed experimental tests of hypothesized population processes, particularly when conservation concerns are involved.
Use of On- Board File System: A Real Simplification for the Operators?
NASA Astrophysics Data System (ADS)
Olive, X.; Garcia, G.; Alison, B.; Charmeau, M. C.
2008-08-01
On-board file system allows to control and operate a spacecraft in new way offering more possibilities. It should permit to provide to the Operator a more abstract data view of the spacecraft, letting them focus on the functional part of their work and not on the exchange mechanism between Ground and Board. Files are usually used in the recent space project but in a restricted way limiting their capabilities. In this paper we describe what we consider as being a file system and its usage on 2 examples among those studied : OBCP and patch. We discuss how files can be handled with the PUS standard and give in the last section some perspectives such as the use of files to standardize all the exchange between Ground / Board and Board / Board.
Shalygin, A V; Vigont, V A; Glushankova, L N; Zimina, O A; Kolesnikov, D O; Skopin, A Yu; Kaznacheeva, E V
2017-07-01
An important role in intracellular calcium signaling is played by store-operated channels activated by STIM proteins, calcium sensors of the endoplasmic reticulum. In stable STIM1 knockdown HEK S4 cells, single channels activated by depletion of intracellular calcium stores were detected by cell-attached patch-clamp technique and their electrophysiological parameters were described. Comparison of the properties of single channels in HEK293 and HEK S4 cells revealed no significant differences in their current-voltage curves, while regulation of store-operated calcium channels in these cell lines depended on the level of STIM1 expression. We can conclude that electrophysiological peculiarities of store-regulated calcium entry observed in different cells can be explained by differences in STIM1 expression.
Obaidat, Rana M; Bader, Ammar; Al-Rajab, Wafa; Abu Sheikha, Ghassan; Obaidat, Aiman A
2011-01-01
The specific aim of this work was to prepare mucoadhesive patches containing tetracycline hydrochloride and carvacrol in an attempt to develop a novel oral drug delivery system for the treatment of mouth infections. The bilayered patches were prepared using ethyl cellulose as a backing layer and carbopol 934 as a matrix mucoadhesive layer. Patches were prepared with different loading amounts of tetracycline hydrochloride and carvacrol. The antimicrobial activity was assessed for the prepared patches using the disc-diffusion method against the yeast Candida albicans and five bacterial strains, including Pseudomonas aeruginosa, Escherichia coli, Bacillus cereus, Staphylococcus aureus, and Bacillus bronchispti. In this work, we highlighted the possibility of occurrence of a synergistic action between carvacrol and tetracycline. The best formulation was selected based on microbiological tests, drug release, ex-vivo mucoadhesive performance, and swelling index. Physical characteristics of the selected formulations were determined. These included pH, patch thickness, weight uniformity, content uniformity, folding endurance, and patch stability.
Patch-clamp amplifiers on a chip
Weerakoon, Pujitha; Culurciello, Eugenio; Yang, Youshan; Santos-Sacchi, Joseph; Kindlmann, Peter J.; Sigworth, Fred J.
2010-01-01
We present the first, fully-integrated, two-channel implementation of a patch-clamp measurement system. With this “PatchChip” two simultaneous whole-cell recordings can be obtained with rms noise of 8 pA in a 10 kHz bandwidth. The capacitance and series-resistance of the electrode can be compensated up to 10 pF and 100 MΩ respectively under computer control. Recordings of hERG and Nav 1.7 currents demonstrate the system's capabilities, which are on par with large, commercial patch-clamp instrumentation. By reducing patch-clamp amplifiers to a millimeter size micro-chip, this work paves the way to the realization of massively-parallel, high-throughput patch-clamp systems for drug screening and ion-channel research. The PatchChip is implemented in a 0.5 μm silicon-on-sapphire process; its size is 3 × 3 mm2 and the power consumption is 5 mW per channel with a 3.3 V power supply. PMID:20637803
Akasaka, Munemitsu; Takamura, Noriko
2012-05-01
Connections between habitat patches can positively influence the number of species in respective patches, providing a basis for preferentially conserving interconnected patches. However, from a regional perspective, it is not known whether conserving multiple sets of interconnected habitat patches would include more species (i.e., show higher gamma diversity) than conserving multiple, unconnected, solitary patches. We studied aquatic macrophytes in 15 sets of unidirectionally interconnected ponds and 19 unconnected ponds and also tested whether alpha and beta diversity, expressed as the number of species and dissimilarity in species composition, respectively, differed between connected and unconnected ponds. We found that gamma diversity was higher in connected ponds than in unconnected ponds, even after controlling for surface area. This resulted from a higher alpha diversity in connected ponds, despite lower beta diversity. These results suggest that connections between habitat patches positively influence diversity at both local and regional scales. When the total surface area available for conservation is limited, interconnected habitat patches should be preferentially conserved.
Resonant frequencies of irregularly shaped microstrip antennas using method of moments
NASA Technical Reports Server (NTRS)
Deshpande, Manohar D.; Shively, David G.; Cockrell, C. R.
1993-01-01
This paper describes an application of the method of moments to determine resonant frequencies of irregularly shaped microstrip patches embedded in a grounded dielectric slab. For analysis, the microstrip patch is assumed to be excited by a linearly polarized plane wave that is normal to the patch. The surface-current density that is induced on the patch because of the incident field is expressed in terms of subdomain functions by dividing the patch into identical rectangular subdomains. The amplitudes of the subdomain functions, as a function of frequency, are determined using the electric-field integral equation (EFIE) approach in conjunction with the method of moments. The resonant frequencies of the patch are then obtained by selecting the frequency at which the amplitude of the surface-current density is real. The resonant frequencies of the equilateral triangular and other nonrectangular patches are computed using the present technique, and these frequencies are compared with measurements and other independent calculations.
Facilitated giga-seal formation with a just originated glass surface.
Böhle, T; Benndorf, K
1994-07-01
A simple technique of tip preparation in patch pipettes is described, which facilitates giga-seal formation. The pipettes were fabricated from thick-walled borosilicate glass tubing (external diameter 2.0 mm, internal diameter 0.5 mm) and the tips could be repeatedly broken in the bath. The pipette resistance correspondingly fell in steps of 3-20 M omega from about 80 M omega to about 2 M omega (double concentrated Tyrode). Scanning electron microscopy showed that the tip obtained after breaking was fairly plain. These broken tips were especially appropriate for patch-clamping. In cardiac myocytes in 11 out of 26 patches with Na+ channel activity, giga-seals developed spontaneously, i.e. without suction. In these patches the amplitude of the mean current with depolarizing pulses to -40 mV was significantly higher in comparison with patches formed under negative pressure. It is concluded that spontaneously sealed patches are most likely of planar configuration and the Na+ channel activity exceeds that in suction-induced patches.
Prediction of Fatigue Crack Growth of Repaired Al-alloy Structures with Double Sides
NASA Astrophysics Data System (ADS)
Benachour, M.; Benachour, N.; Benguediab, M.; Seriari, F. Z.
During navigation, aircrafts are subject to fatigue damage. In order to rehabilitate damaged structures some techniques are often used to resolve this problem. Efficient repair technique, called composite patch repair, was used to reinforce the damaged structures and stop cracks. In this paper, effect of composite patch repair (Boron/Epoxy) on fatigue crack growth (FCG) was investigated on 2219 T62 Al-alloy. Effects of double patch repair in single notch tensile specimen (SENT) on FCG were studied and compared to single patch repair. Results show beneficial effect of patch repair on fatigue life and FCGR in comparison with the un-patched specimen. In addition, effect of mean stress characterized by stress ratio was highlighted. Fatigue behavior of investigated Al-alloy was compared.
Is there a risk of active sensitization to PPD by patch testing the general population?
Thyssen, Jacob Pontoppidan; Menné, Torkil; Nielsen, Niels Henrik; Linneberg, Allan
2007-08-01
Para-phenylenediamine (PPD), a constituent of permanent hair dyes, may cause contact allergy in exposed individuals. It has previously been questioned whether a patch testing with PPD in population-based epidemiological studies is entirely safe. The Glostrup allergy studies patch tested the same cohort twice. In 1990, 567 persons were patch-tested and only one person had a (+) positive reaction to PPD. In 1998, 540 persons were re-invited to a new patch test and 365 (participation rate 68%) were re-tested. There were no positive reactions to PPD. These studies indicate that patch testing with PPD in individuals with no previous positive reactions to PPD or with only one previous positive reaction does not cause active sensitization and can be performed with minimal risk.
Shiffman, Saul; Ferguson, Stuart G
2008-10-01
The objective of this analysis was to assess the efficacy of a 21 mg/24-h nicotine patch for the reduction of craving throughout the waking day, compared both to placebo, and to a 15 mg/16-h patch differing pharmacokinetic profile over the day. The primary end-point was craving during the evening hours, because previous research suggested that smoking relapse was particularly likely at that time. Data were drawn from two similar randomized clinical trials among nicotine-dependent smokers who were quitting smoking: Study 1 compared the 21 mg/24-h patch to a placebo patch, while Study 2 compared the 21 mg/24-h patch to a 15 mg/16-h nicotine patch. In both studies, subjects (Study 1: n = 102; Study 2: n = 244) were prompted by an electronic diary to rate their craving multiple times per day during a 1 week baseline period, and for up to 2 weeks after quitting. For analysis, the day was divided into five blocks: morning (up to 10:59 a.m.), mid-day (11:00 a.m.-1:59 p.m.), afternoon (2:00 p.m.-4:59 p.m.), evening (5:00 p.m.-8:59 p.m.), and late night (9:00 p.m. onwards). The individual craving ratings were divided into three intervals based on time since quitting: Days 1-3, 4-7, and 8-14. The 21 mg/24-h nicotine patch resulted in significantly lower craving during all post-quit intervals, at each time of day, both compared to placebo (Study 1), and compared to the 15 mg/16-h nicotine patch (Study 2). Study 2 saw a significant treatment by interval interaction: in later time intervals, the difference in craving experience between 24- and 16-h patch conditions shrunk--while remaining significantly different--as overall levels of craving experienced by subjects in the two groups dropped. Adverse events reported in both studies tended to be mild and transient, consistent with the well characterized adverse event profile of nicotine patches. Study 1 demonstrated that a 21 mg/24-h patch was effective in reducing craving throughout the day, including the evening period when relapse risk is heightened. A further study comparing the 21 mg/24-h patch to a 15 mg/16-h nicotine patch found that craving was significantly lower at all times of day for smokers using the 21 mg/24-h patch. The studies were limited in that craving was only monitored for the first 2 weeks of quitting (when craving is most prominent), and cannot elucidate the impact of patch use on craving outside of this time. Also, there was substantial attrition of the sample over time, partly due to relapse in all conditions.
Mechanical Development of a Very Non-Standard Patch Array Antenna for Extreme Environments
NASA Technical Reports Server (NTRS)
Hughes, Richard; Chamberlain, Neil; Jakoboski, Julie; Petkov, Mihail
2012-01-01
This paper describes the mechanical development of patch antenna arrays for the Juno mission. The patch arrays are part of a six-frequency microwave radiometer instrument that will be used to measure thermal emissions from Jupiter. The very harsh environmental conditions in Jupiter orbit, as well as a demanding launch environment, resulted in a design that departs radically from conventional printed circuit patch antennas. The paper discusses the development and qualification of the Juno patch array antennas, with emphasis on the materials approach that was devised to mitigate the effects of electron charging in Jupiter orbit.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wilson, L.E.; McGuire, D.R.
1984-05-01
This final report summarizes the technical reports for Phase III of this project. The third phase included the operation, maintenance, upgrade and performance reporting of a 10,080 square foot Solar Industrial Process Heat System installed at the Famariss Energy Refinery of Southern Union Refining Company near Hobbs, New Mexico. This report contains a description of the upgraded system, and a summary of the overall operation, maintenance and performance of the installed system. The results of the upgrade activities can be seen in the last two months of operational data. Steam production was significantly greater in peak flow and monthly totalmore » than at any previous time. Also monthly total cost savings was greatly improved even though natural gas costs remain much lower than originally anticipated.« less
An experimental test of whether habitat corridors affect pollen transfer.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Townsend, Patricia A.; Levey, Douglas J.
Abstract. Negative effects of habitat fragmentation are thought to be diminished when habitat patches are joined by a corridor. A key assumption is that corridors facilitate exchange rates of organisms between otherwise isolated patches. If the organisms are pollinators, corridors may be important for maintaining genetically viable populations of the plants that they pollinate. We tested the hypothesis that corridors increase the movement of insect pollinators into patches of habitat and thereby increase pollen transfer for two species of plants, one pollinated by butterflies (Lantana camara) and the other by bees and wasps (Rudbeckia hirta). We worked in an experimentalmore » landscape consisting of 40 greater than or equal to 1-ha patches of early-successional habitat in a matrix of forest. Within each of eight experimental units, two patches were connected by a corridor (150 X 25 m), and three were not. Patch shape varied to control for the area added by the presence of a corridor. Differences in patch shape also allowed us to test alternative hypotheses of how corridors might function. The Traditional Corridor Hypothesis posits that corridors increase immigration and emigration by functioning as movement conduits between patches. The Drift Fence Hypothesis posits that corridors function by ‘‘capturing’’ organisms dispersing through the matrix, redirecting them into associated habitat patches. Using fluorescent powder to track pollen, we found that pollen transfer by butterflies between patches connected by a corridor was significantly higher than between unconnected patches (all values mean plus or minus 1 SE: 59% plus or minus 9.2% vs. 25% plus or minus 5.2% of flowers receiving pollen). Likewise, pollen transfer by bees and wasps was significantly higher between connected patches than between unconnected patches (30% plus or minus 4.2% vs. 14.5% plus or minus 2.2%). These results support the Traditional Corridor Hypothesis. There was little support, however, for the Drift Fence Hypothesis. To generalize our results to a larger scale, we measured the probability of pollen transfer by butterflies as a function of distance along a 2000 X 75 m corridor. Pollen transfer probability exponentially declined with respect to distance and successfully predicted pollen transfer probability on the scale of our previous experiment. These results suggest that corridors facilitate pollen transfer in fragmented landscapes.« less
Ali, Qasim; Bauch, Chris T.; Anand, Madhur
2015-01-01
Background The transportation of camp firewood infested by non-native forest pests such as Asian long-horned beetle (ALB) and emerald ash borer (EAB) has severe impacts on North American forests. Once invasive forest pests are established, it can be difficult to eradicate them. Hence, preventing the long-distance transport of firewood by individuals is crucial. Methods Here we develop a stochastic simulation model that captures the interaction between forest pest infestations and human decisions regarding firewood transportation. The population of trees is distributed across 10 patches (parks) comprising a “low volume” partition of 5 patches that experience a low volume of park visitors, and a “high volume” partition of 5 patches experiencing a high visitor volume. The infestation spreads within a patch—and also between patches—according to the probability of between-patch firewood transportation. Individuals decide to transport firewood or buy it locally based on the costs of locally purchased versus transported firewood, social norms, social learning, and level of concern for observed infestations. Results We find that the average time until a patch becomes infested depends nonlinearly on many model parameters. In particular, modest increases in the tree removal rate, modest increases in public concern for infestation, and modest decreases in the cost of locally purchased firewood, relative to baseline (current) values, cause very large increases in the average time until a patch becomes infested due to firewood transport from other patches, thereby better preventing long-distance spread. Patches that experience lower visitor volumes benefit more from firewood movement restrictions than patches that experience higher visitor volumes. Also, cross–patch infestations not only seed new infestations, they can also worsen existing infestations to a surprising extent: long-term infestations are more intense in the high volume patches than the low volume patches, even when infestation is already endemic everywhere. Conclusions The success of efforts to prevent long-distance spread of forest pests may depend sensitively on the interaction between outbreak dynamics and human social processes, with similar levels of effort producing very different outcomes depending on where the coupled human and natural system exists in parameter space. Further development of such modeling approaches through better empirical validation should yield more precise recommendations for ways to optimally prevent the long-distance spread of invasive forest pests. PMID:26430902
Ilett, Kenneth F; Hale, Thomas W; Page-Sharp, Madhu; Kristensen, Judith H; Kohan, Rolland; Hackett, L Peter
2003-12-01
Our objective was to assess the extent of exposure to nicotine and cotinine in breast-fed infants during maternal smoking and later during maternal use of the nicotine transdermal patch to achieve smoking cessation. Fifteen lactating women (mean age, 32 years; mean weight, 72 kg) who were smokers (mean of 17 cigarettes per day) participated in a trial of the nicotine patch to assist in smoking cessation. Serial milk samples were collected from the women over sequential 24-hour periods when they were smoking and when they were stabilized on the 21-mg/d, 14-mg/d, and 7-mg/d nicotine patches. Nicotine and cotinine in milk were quantified by HPLC, and infant dose was calculated. Plasma concentrations of nicotine in the breast-fed infants were assessed, and the infants were also clinically assessed. Nicotine and cotinine concentrations in milk were not significantly different between smoking (mean of 17 cigarettes per day) and the 21-mg/d patch, but concentrations were significantly lower (P <.05) when patients were using the 14-mg/d and 7-mg/d patches than when smoking. There was also a downward trend in absolute infant dose (nicotine equivalents) from smoking or the 21-mg patch through to the 14-mg and 7-mg patches (P <.05 at both 14-mg and 7-mg doses, compared with smoking). Milk intake (shown as median and 25th to 75th percentile) by the breast-fed infants was similar while their mothers were smoking (585 mL/d [507-755 mL/d]) and subsequently when their mothers were using the 21-mg (717 mL/d [504-776 mL/d]), 14-mg (731 mL/d [535-864 mL/d]), and 7-mg (619 mL/d [520-706 mL/d]) patches (chi(2) = 3.19, P =.364). We conclude that the absolute infant dose of nicotine and its metabolite cotinine decreases by about 70% from when subjects were smoking or using the 21-mg patch to when they were using the 7-mg patch. In addition, use of the nicotine patch had no significant influence on the milk intake by the breast-fed infant. Undertaking maternal smoking cessation with the nicotine patch is, therefore, a safer option than continued smoking.