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The versatile reverse flow sural artery neurocutaneous flap: A case series and review of literature

The versatile reverse flow sural artery neurocutaneous flap: A case series and review of literature

Soft tissue defects around the foot and ankle region often present an awkward problem to the orthopaedic surgeons. Tendons and bones are frequently exposed after trauma because of the thinness of the subcutaneous tissue. Tradi- tionally, local flaps were used for resurfacing but their use is limited by their size and arc of rotation. Reverse flow flaps such as anterior tibial artery flap and posterior tibial artery flap require the sacrifice of major arteries. Free flap is currently the treatment of choice for large soft tissue defects of the distal extremity and it solves the problem of donor site morbidity in the immediate vicinity of the flap. It is however a technically demanding procedure for sur- geons with less microsurgical experience. Furthermore in a few cases of trauma with damaged or occluded major vessels, where a free flap may be potentially hazardous, the reverse sural artery flap can prove to be one of the few safe options for soft tissue coverage [1]. The accompany- ing arteries of the lesser saphenous vein and sural nerve have been utilized with success for harvest of reverse flow sural flap [2]. The sural nerve remains the anatomic land- mark for the inclusion of vessels in pedicle of the flap. The sural artery reverse flow flap is nourished by the lower- most perforating branch of the peroneal artery. Since the introduction of this flap by Masquelet [3] in 1992, it has become one of the favourite among reconstructive sur- geons. It is the flap of first choice in our centre. In the present report, the results of reverse flow sural neurocuta- neous flaps done at our centre is presented along with some thought provoking ideas for the future.

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Boundary layer flow beneath an internal solitary wave of elevation

Boundary layer flow beneath an internal solitary wave of elevation

The flow reversal seen in the bottom boundary in the decelerating part of the wave-induced flow was shown to be similar in nature to that found under surface solitary waves. 21–23 Liu et al. 22 suggest that the reversal is a result of a phase lag between the irrotational and rotational velocity components. Carr and Davies 25 and Carr et al. 26 presented experimental evidence of a similar flow reversal at the lower boundary under an ISW of depression in the decelerating part of the wave-induced flow aft of the crest but conjectured that the flow reversal was a result of boundary layer separa- tion in the adverse pressure gradient region. In both in- stances, however, a reverse flow is seen in the decelerating part of the flow 共aft of the wave crest/trough兲. Hence, it may be that the reverse flow under an ISW of depression is also the result of a phase lag between the irrotational and rota- tional velocity components and is not the result of the ad- verse pressure gradient region as previously proposed. 16,25,26 On the other hand, the wave-induced flow under ISWs of differing polarity have significant differences and a direct comparison of the two should be made with caution. For example in the elevation case, there is strong shear 共i兲 at the crest of the wave, where the wave-induced velocity changes sign, and 共ii兲 at the lower boundary where there is a no-slip requirement. The velocity gradient is oppositely signed at the crest and the lower boundary, respectively, for example see Moum et al. 6 Fig. 9. Hence, oppositely signed vorticity is injected into the wave core at the crest and at the lower boundary, respectively. This is in contrast to the depression case where the wave core is bounded above by a free surface and below by the wave trough. The free surface does not generate the same kind of high stresses that the lower solid boundary does in the elevation case and, in consequence, input of vorticity into the wave core is significantly different in the two cases. Moreover, the wave-induced shear stress generated at the bottom boundary beneath an ISW of eleva- tion is expected to be higher than in the depression counter- part as the pycnocline is located nearer the bed and so the wave-induced velocity field is stronger.

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Modeling Thermal Oxidation of Coal Mine Methane in a Non-Catalytic Reverse-Flow Reactor

Modeling Thermal Oxidation of Coal Mine Methane in a Non-Catalytic Reverse-Flow Reactor

Compressed air from the air compressor through the gas regulating valve and pressure-relief valve mixes with the methane from Methane cylinder in the mixer, which is then fed into the oxidation bed. The time relay controls the periodic closing and opening of the electromagnetic valve to control the the cycle gas flow direction. To initiate the reaction, the reverse flow reactor was preheated from an ambient temperature to about 950 °C using an electrical heater in the central position of the reactor. Once the reactor was preheated, the burner was extinguished and the lean methane mixture was supplied to the reactor. The heating temperature and heating power in the startup process is controlled by the temperature control instrument. The intake and exhaust composition is tested by gas chromatography. Electric heaters mounted in the middle of TFRR were used only for preheating the monoliths to enable the start of normal operations. There are 12 thermocouple measuring points arranged along the axis of the oxidation bed, the output signal of the thermocouple connected to the computer can monitor the transient temperature field in the TFRR. The direction of the gas flow was controlled by four solenoid valves.

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A radiofrequency heated reactor system for post combustion carbon capture

A radiofrequency heated reactor system for post combustion carbon capture

To demonstrate this effect in practice, the desorption cycles have been carried out both in direct and reverse flow mode. It can be seen in Figure 7 that the sorption capacity is gradually decreases after five absorption/desorption cycles and then it remains a constant value of 15 wt.%. The sorption capacity remains the same after desorption in direct and reverse flow mode. The specific surface area and pore volume of CaO fresh and spent sorbents are listed in Table 3. It should be mentioned that amount of CO 2 desorbed from the sorbent during the desorption

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MANIPULATION OF FLOW OVER BACKWARD STEP

MANIPULATION OF FLOW OVER BACKWARD STEP

The experimental results show that the various flow regimes are characterized by typical variation of separation length with Reynolds number 4 .Also an additional region of flow separation at the downstream of the step is found apart from the primary recirculation region 5 . Experimental investigation for the flow of Reynolds number 100 to 8000 shows the size of the reverse flow region is function of the Reynolds number 6 .

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A REVIEW PAPER ON DESIGN, DEVELOPMENT CYCLONE SEPARATOR

A REVIEW PAPER ON DESIGN, DEVELOPMENT CYCLONE SEPARATOR

A. Sakin, et al.[ 2019] Performance characteristics of a novel cyclone with tangential inlet were presented in axial and reverse flow operation modes. 3-D and unsteady governing equations were used for the numerical solution of the two- phase turbulent flow in the cyclone separator. The Eulerian approach was used to solve the flow field, and the Reynolds Stress Model (RSM) with the scalable wall function was employed for the numerical study. The Lagrangian approach with the Discrete Phase Model was used to calculate the discrete phase by releasing particles from the inlet surface. CFD calculations were run for different geometric configurations to analyze the performance of the cyclones regarding pressure drop, cut-off diameter, and fractional efficiency. Axial and tangential velocity profiles are presented at the defined sections. The computational results of pressure drop, velocity field, and separation efficiency were also compared for the axial and reverse flow cyclones at the same flow rate. The results show that pressure drop and collection efficiency in reverse flow mode are higher than that of the axial flow operation. However, axial flow cyclones seem to be more efficient for small particles comparing to reverse flow cyclones.[1]

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Rapid and Sensitive Detection of H7N9 Avian Influenza Virus by Use of Reverse Transcription–Loop Mediated Isothermal Amplification

Rapid and Sensitive Detection of H7N9 Avian Influenza Virus by Use of Reverse Transcription–Loop Mediated Isothermal Amplification

For effective global monitoring and control of the H7N9 epi- demic, it is necessary that the characterization of influenzalike cases, especially severe pneumonia in humans, and H7N9 avian influenza virus (AIV) detection in migratory birds and poultry be stringent (6). Currently, the sensitivity of the immunological col- loidal-gold test method is quite low (7), making it difficult to detect H7N9 in samples from clinical cases. Quantitative real-time reverse transcription-PCR (rRT-PCR) of the H7N9 avian influ- enza virus hemagglutinin (HA) and neuraminidase (NA) genes (8, 9, 10), while being both sensitive and specific, requires expensive equipment, professional technology, and a complicated method- ology which is not suitable for on-site detection or laboratories with poor conditions, especially in developing countries. There is, therefore, an urgent need to establish a simple, rapid, and sensitive method for the detection of the new H7N9 influenza virus.

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Study of Volume Reduction by Reverse Osmosis and Evaporation of Waste Water

Study of Volume Reduction by Reverse Osmosis and Evaporation of Waste Water

A reverse osmosis membrane acts as the semi permeable barrier to flow in the RO process, allowing selective passage of a particular species (solvent, usually water) while partially or completely retaining other species (solutes).The concentrated solution discharged as waste from the RO system is referred to as REJECT, while the cleaner solution coming through the product end is called as PERMEATE.

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Sustainable Supply Chain Network Design: A Review on Quantitative Models Using Content Analysis

Sustainable Supply Chain Network Design: A Review on Quantitative Models Using Content Analysis

Pourmohammadi, H., Rahimi, M., & Dessouky, M. (2008, January). Sustainable reverse logistics for distribution of industrial waste/byproducts: A joint optimization of operation and environmental costs. In Supply Chain Forum: An International Journal (Vol. 9, No. 1, pp. 2-17). Taylor & Francis. Pozo, C., Ruiz-Femenia, R., Caballero, J., Guillén-Gosálbez, G., & Jiménez, L. (2012). On the use of Principal Component Analysis for reducing the number of environmental objectives in multi- objective optimization: application to the design of chemical supply chains. Chemical Engineering Science, 69(1), 146-158.

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On Varieties of Reverse Wiener Like Indices of a Graph

On Varieties of Reverse Wiener Like Indices of a Graph

Abstract. In this paper Reverse Wiener index, Reverse Detour Wiener index, Reverse Circular Wiener index Reverse Harary index, Reverse Detour Harary index, Reverse Circular Harary index, Reverse Reciprocal Wiener index, Reverse Detour Reciprocal Wiener index, Reverse Circular Reciprocal Wiener index, Reverse Hyper Wiener index, Reverse, Detour Hyper Wiener index, Reverse Circular Hyper Wiener index, Reverse Gutman Wiener index, Reverse Detour Gutman Wiener index, Reverse circular Gutman Wiener index are defined using the diameter and Detour diameter of a graph and the above indices have been estimated for the Cartesian product P 2 and C n .

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A Single Inductor Dual Buck Inverter

A Single Inductor Dual Buck Inverter

The most attractive advantage of the dual buck topologies is the high reliability. Firstly, without adding the extra dead time, the dual buck topologies can solve the shoot through problem. Secondly, compared to the traditional H-bridge inverter, the current will not flow through the body diodes of the switches in the dual buck topologies which mean no reverse recovery problem exists in the MOSFET phase legs. Considering the above two aspects, the dual buck topologies can achieve high reliability without the shoot through and reverse recovery issues. However, the main drawback of the dual buck topologies is the low magnetic utilization. In each power delivering and freewheeling modes, the current only flow through half of the inductance, which means the other half of the inductance, is wasted in each working condition. The low utilization of the inductance makes the increasing of the weight and volume for the whole system. To solve this problem, a concept of single inductor dual buck full bridge inverter [7] is proposed. The circuit diagram of the inverter is shown in fig.1.

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Suggested Strategies in Water Treatment by Using Situ Pressure in Reverse Osmosis

Suggested Strategies in Water Treatment by Using Situ Pressure in Reverse Osmosis

dominant method in desalting [3]. Spain and Italy hold the majority of the European desalination capacity, with each country holding 2.6% of world production capacity; 69% of desalination plants in Spain use RO technolo- gy, while only 20% of plants in Italy use RO, Japan holds 3.7% of global production [4] and has been using seawater RO technology since 1974. Countries in South America, such as Chile, have recently implemented large desalination plants [5], and Australia has been battling a water crisis with new RO installations from Mel- bourne to the Gold Coast [6]. Membranous process probably turns saltwater into fresh one. One of the most mi- nuscule membranes in separating process is osmosis membranes. In reverse osmosis, the water moves from higher concentration to the lower one due to the pressure entering the salt water, furthermore, water moves against the Salts concentration gradients and natural direction osmosis. Pure water passes through the membrane, thus, salt remains in the other side of the membrane. In this process, in addition to salt ions, the other substances in water such as suspended particles, viruses, minerals, organic matter and microbes are separated from the wa- ter. In this method, pressure must be increased by rising the amount of solute in water. Thus, the required pres- sure for desalination is 10 to 15 bars for the brackish water and about 54 to 80 bars for seawater [7]. Therefore, the purpose of this research is utilizing the pressure, which is available at harvested areas. Moreover, based on the obtained results, the most efficient and practical option for the regional and climatic conditions is suggested to be a small step to improve water crisis.

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Development and Validation of a Method for Simultaneous Determination of Metformin and Saxagliptin in a Formulation by RP HPLC

Development and Validation of a Method for Simultaneous Determination of Metformin and Saxagliptin in a Formulation by RP HPLC

flow rate of 0.6 mL/min and by employing UV detection at 220 nm wavelength. The retention time of Metformin and Saxagliptin were found to be 4.38 min and 6.92 min, respectively. The method was validated as per ICH guidelines. The limit of detection (LOD) and limit of quantification (LOQ) of Metformin were found to be 0.112 µg/mL and 0.373 µg/mL, respectively, while those of Saxag- liptin were found to be 0.029 µg/mL and 0.096 µg/mL, respectively. The method was found to be rapid, sensitive, linear, specific, accurate, precise and economic for the quality control and stabili- ty assays of Metformin and Saxagliptin in marketed tablet dosage forms.

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Nappe flow regime energy loss in stepped chutes equipped with reverse inclined steps: experimental development

Nappe flow regime energy loss in stepped chutes equipped with reverse inclined steps: experimental development

Moreover, other work on the flow condition, and energy dissipation in stepped spillways equipped with inclined steps or an end sill, have been conducted by [7-9] who investigated the effect of inclined steps and an end sill together on the flow pattern and energy loss rate. Among all investigations conducted on spillways, the research performed by [10, 11] can be singled out. In his research, the height of the applied end sills was considered at 5, 10 and 15 mm on various step slopes and this led to presenting a relationship between the relative energy loss and the drop number. The result of his investigation demonstrated that relative energy loss increased 8% due to the existence of an end sill. The drop number, which is equal to q2/gHT3 (where q is the flow discharge per channel width, g is gravity acceleration, and HT its total drop height), is one of the most important energy dissipation parameters. [12-14] examined three inclined steps degrees (10o, 20 o, and 30o) and end sill to determine the energy dissipation rate separately. They noted that using an end sill is the best approach to increase the energy dissipation rate.

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Experimental and Computational Investigation of Thermal-Flow Characteristics of Gas Turbine Reverse-Flow Combustor

Experimental and Computational Investigation of Thermal-Flow Characteristics of Gas Turbine Reverse-Flow Combustor

During the meshing process, special effort has been expended to mesh hundred of small impinging holes. Two different methods have been used. One method sets the hole as an interior surface with at least ten nodes and cells on it as shown in Fig.3.4a. Another leaves the holes as part of interior volume with denser cells being meshed surrounding the holes as shown in Fig.4.3b. The first method needs more work and computational time because of the larger number of mesh sizes, while the second method can save more than 30% of computational time. It was initially thought that the first method would produce a better result because the flow is expected to drastically accelerate at the impinging holes interface. However, comparison of these two methods shows the difference is less than 1%. Considering the minimal benefits that can be obtained by the first method, the second method is therefore selected for this project.

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Use of Simulation for Waste Management and Reverse Material Flow

Use of Simulation for Waste Management and Reverse Material Flow

The wastes which infiltrate into the environment are created from unexpended materials and products. The envi- ronment can manage a great amount of waste, but this process requires time. Nature always attempts to achieve the balance . However, degradation of some materials in nature takes about 1000 years, which is a very long pe- riod of time in terms of the length of a human life, also in view of the rising trend of wastes generation. The need for appropriate waste management is steadily rising, as does the production of wastes and our living standards. Incorrect waste management has a negative impact on all components of the environment. Waste management, their processing and recycling additionally contribute to human health protection and preservation of a healthy environment. Another benefit is in the form of raw materials extraction, the global supplies of which are constantly reducing. One of the possible ways of effective waste management is improving environmental awareness but the science brings different ways of solution, for example in connection with waste management and simulation of wastes flow. The paper presents one of this ways by help with the creation of centralized collection point of wastes using a universal model which is usable for different countries with the problem of wastes and waste management. Keywords: waste, simulation, model, centralized collection point

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Simulation of small size divertor tokamak plasma edge under effect of toroidal magnetic field reversal

Simulation of small size divertor tokamak plasma edge under effect of toroidal magnetic field reversal

Asymmetries between the divertor legs of small size divertor (SSD) tokamak plasma edge are noticed to reverse when the direction of toroidal magnetic field is reversed. In the present paper the small size divertor tokamak plasma edge under effect of toroidal magnetic field reversal is simulated by B2SOLPS0.5.2D fluid transport code. The simulation demonstrate the following results: 1) Parallel (toroidal) flow flux and Mach number up to 0.6 at higher plasma density re- verse with reverse toroidal magnetic direction in the edge plasma of small size divertor tokamak. 2) The radial electric field is toroidal magnetic direction independence in edge plasma of small size divertor tokamak. 3) For normal and reverse toroidal magnetic field, the strong ITB is located between the positions of the maximum and minimum values of the radial electric field shear. 4) Simulation result shows that, the structure of radial electric field at high field side (HFS) and low field side (LFS) is different. This difference result from the change in the parallel flux flows in the scrape off layer (SOL) to plasma core through separatrix. 5) At a region of strong ra- dial electric field shear, a large reduction of poloidal rotation was observed. 6) The poloidal rotation is toroidal magnetic field direction de- pendence.

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Poverty and unemployment in Spain during the 2008's financial crises

Poverty and unemployment in Spain during the 2008's financial crises

Providing aid to Less Developed Countries (LDCs) is used to fill the saving and the foreign exchange gaps. Domestic saving is important for domestic investment to take place, and if this is not sufficient, investment projects are financed by a flow of development assistance from donors. In development theory, the split of pro-aid and anti-aid arguments has been clear, and the protagonists of foreign aid argue that the major deficit of growth and development in the least developed countries are capital, foreign exchange and technical knowledge and they can’t generate these resources in their initial stage of development. Foreign aid can be helpful in pushing the growth rate by giving a solution for these bottlenecks; while antagonists of aid argue that, foreign aid may not be necessarily leading to the growth and development of recipient countries since their problems may go beyond either savings or foreign exchange constraints, and even foreign resources may not be properly utilized in the absence of proper macroeconomic policy, and may use to finance reverse flows (Pankaj, 2005, Serieux, 2011 and Girma, 2015).

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An Integrated Approach to Vehicle Recycling Facilities

An Integrated Approach to Vehicle Recycling Facilities

The logistics process usually begins from raw materials, up to the end process at the consumer level. On the other hand, reverse logistics is concerned on procedures and methods of recycling and dismantling, maintenance and repairs for product and materials. All these processes and activities in reverse logistics systems incur costs and must be included in the design of the system. The project put more emphasis on the different methods and techniques that are known to be effective in developing an integrated vehicle recycling facility.

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Probiotic lactobacillus and estrogen effects on vaginal epithelial gene expression responses to Candida albicans

Probiotic lactobacillus and estrogen effects on vaginal epithelial gene expression responses to Candida albicans

A MultiBead W multiplex immunoassay (Enzo Life Sciences, Ann Arbor, MI) was used to quantify cytokines excreted into the basolateral growth media by VK2 cells. Using the manufacturer’s instructions, culture superna- tants were incubated with allophycocyanin -labeled 4 μm and 5.4 μm anti-human cytokine antibody-coated capture beads that were washed in 96 well filter plates on a vacuum manifold (Enzo) set at 100 mbar vacuum. The beads were incubated with phycoerythrin-labeled streptavidin and washed on the vacuum manifold. The beads were analyzed in a C6 W digital flow cytometer (Accuri Cytometers) that was calibrated with Rainbow 8-peak W and Allophycocyanin 6-Peak Calibration Parti- cles W (Spherotech). Each size bead population was gated with forward and side scatter dot plots and individual allophycocyanin fluorescence intensities corresponding to specific anti-cytokine antibody were gated with an emission detector filtered at 675 nm (FL-4) after excita- tion with a 640 nm laser. Fluorescence of phycoerythrin was used to obtain quantitative information by excita- tion with a laser at 488 nm and detection at 585 nm (FL-2). Results were obtained from a standard curve in Assay Designs MultiBead W analysis software using stan- dards supplied by the kit manufacturer (Enzo).

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