bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment and Inclusion of Capillary Pressure/Relative Permeability Hysteresis Effects in Downhole Water Sink (DWS) Well Technology for Water Coning Control
Authors: Inikori Solomon O. , Wojtanowicz Andrew K.
Published: April 2020

The objective of this study is to assess the effects of capillary pressures and relative permeability hysteresis on the performance of wells using the downhole water sink (DWS) technology for water coning control.

In the study a commercial reservoir simulator has been adopted to evaluate well performance under conditions of stabilized oil production/water drainage rates for various combinations of these rates. Operational domain of water-free oil production, Inflow Performance Window (IPW), was used to quantify the effects of capillary pressure transition zone and relative permeability hysteresis on the water coning - control performance of DWS wells. Field data from wells in Canada, West Africa and Louisiana exhibiting severe problems of water coning were used in this study.

The simulation results show that the basic concept of the DWS is unchanged by the inclusion of capillary pressure and relative permeability hysteresis. However, these effects may cause considerable reduction in the size of the water-free oil production domain and lead to increase in water production.

The results also indicate that, for the same reservoir, converting conventional wells with prior water coning history to DWS application would not be as beneficial as DWS completions on new wells. Thus the effect of drainage-imbibition relative permeability hysteresis should be included in the DWS well design practice.
Smart Sensors for Controlling Oil-Water Separation Processes
Authors: Jaworski Artur J. , Dyakowski Tomasz , Davies Graham A.
Published: April 2020

In this paper we present a novel approach to designing sensors and instrumentation for monitoring and controlling multiphase processes. Our concept is based on using distributed sensor arrays, embedded within the vital plant components and thus forming smart structures. Distributed information obtained from such devices, coupled with appropriate data processing, could improve our understanding of the nature of multiphase processes and hence improve plant operation. We discuss the requirements for such sensors and, in the experimental part of this paper, present a short case study, conducted at UMIST Pilot Plant facility, to highlight the benefits of using smart sensing techniques in a process environment. We hope that this paper will open a general discussion on sensing multiphase flows.
A Numerical Model Coupling Reservoir and Horizontal Well Flow Dynamics: Applications in Well Completions, and Production Logging
Authors: Vicente Ronaldo , Sarica Cem , Ertekin Turgay
Published: April 2020

A fully implicit, three-dimensional simulator with local grid refinement around the wellbore is developed to solve reservoir and horizontal well flow equations simultaneously, for single-phase liquid and gas cases. The model consists of conservation of mass and Darcy’s law in the reservoir, and mass and momentum conservation in the wellbore for isothermal conditions. Establishing the continuity of pressure and preserving mass balance at the sandface satisfy the coupling requirements. The proposed simulator is tested against and verified with the results obtained from a commercial code ECLIPSE-100™, and available public domain simulators and semi-analytical models.

The proposed model can be used for multiple purposes such as well productivity prediction, well length optimization, completion design and optimization, and production logging interpretation. Different completion scenarios and reservoir anisotropy are simulated and their effects on the productivity of the horizontal wells are discussed. Completion cases include open-hole, partial and full completions with perforations and slotted liners. During the production logging of a horizontal well, the coil tubing reduces the wellbore cross sectional area and may cause substantial changes in the wellbore flow behavior. Depending on the well and coil tubing diameters, a significant difference between the actual production rates and the rates obtained from a production log can be observed.
A CFD Based Correlation for Erosion Factor for Long-Radius Elbows and Bends
Authors: Wang Jianrong , Shirazi Siamack A.
Published: April 2020

A model for predicting sand erosion in 90 degree elbows and bends has been developed based on computational fluid dynamics (CFD), particle tracking and erosion data. After the flow field was obtained from the flow (CFD) model, particles were introduced into the flow and particle trajectories were computed using a Lagrangian approach. A model was also implemented that accounts for the interaction between the particles and the target material. Based on predicted particle impingement velocities, erosion rates and penetration rates were predicted using the empirical equations for erosion ratio. The predicted penetration rates are compared with available experimental data for several different elbows. The agreement between the predicted penetration rates and the experimental data is good. The erosion model is applied to standard (short-radius) elbows and long-radius elbows to understand why long radius elbows have lower erosion (penetration) rates. In addition, based on many predictions and erosion rate results, a new CFD based correlation is developed and is recommended as a first-order approximation for engineering calculations to account for effects of elbow radius on erosion in long-radius elbows. This equation is for computing the ratio of the wall thickness loss (or the penetration rate) in a long-radius elbow to the penetration rate of a standard (short-radius) elbow. The results from the correlation agree well with the trend of available data in the literature.
New Developments in Multiphase Flow Modelling and Field Data Verification
Authors: Nossen Jan , Shea Richard H. , Rasmussen Jon
Published: April 2020

The OLGA Verification and Improvement Project for Three-Phase Flow is a joint industrial project sponsored by 11 oil companies to improve the flow models in OLGA and verify the improved code against field data. To improve the stratified flow model, correlations for wall shear and entrainment were improved based on published experimental data as well as unique in-house data. For slug flow, the translational velocity and slug body pressure drop have been improved using models from literature. The improved OLGA code has been compared to the AGA data bank for wet gas pipelines and to data from Prudhoe Bay. The comparisons show that systematic prediction errors are greatly reduced.
Kinetic of Nonelastic Processes in the Flowing Plasma
Authors: Sado Jerzy
Published: April 2020

The nonelastic, microscopic internal processes are generated in flowing plasma. All processes have living time different from zero. So, their influence on subsonic plasma flow can be significant. Presented paper is concerned on influence of rate collisions internal processes on subsonic flow of low temperature plasma.
Solutions of the Right Classes for Laminated Composites Satisfying Interlamina Physics
Authors: Surana K. S. , Ngyun H.
Published: April 2020

This paper presents a new theoretical and computational framework for computing solutions of right classes for laminated composites using 2D p-version least squares finite element formulation incorporating the correct physics of interlamina behavior. At the interface between two laminas of dissimilar materials we have continuity of displacements u, v, stresses σyy, τxy, and strain εxx, while the stress σxx and the strains εyy and γxy are discontinuous. Thus, a finite element formulation, incorporating the physics of laminate behavior, would require interpolation of u, v, εxx, σyy and τxy instead of u, v, σxx, σyy and τxy which is generally the case in most mixed formulations. In the p-version LSFEF presented here, we interpolate u, v and σyy, τxy (εxx = ∂u/∂x is used to eliminate εxx as a variable) using appropriate p-version interpolations which would ensure correct interlamina behavior of these components. When the mating lamina properties are different, interlamina discontinuity of σxx, εyy and γxy is automatically generated due to dissimilar material properties of the laminas. In this formulation interlamina jumps in σxx, εyy and γxy do not constitute singularities, hence mesh refinements and higher p-levels are not needed in the vicinity of inter-lamina boundaries. The major thrust of this paper is to construct interpolations for the dependant variables that are of right classes in appropriate spaces so that a sequence of converged solutions in these spaces may be computed which, when converged, would yield a numerical solution that has exactly the same characteristics (in terms of continuity and differentiability) as the analytical or theoretical (strong) solution.
Models for Inspected Systems Under General Degradation
Authors: Klutke Georgia-Ann
Published: April 2020

Many protective devices, as well as spare and standby systems, exhibit what are known as non self-announcing failures; that is, failures can be observed only by inspection. Inspections can usually reveal only whether the device is operational or not, and not the level of deterioration of the device. This paper considers the availability of such systems when degradation is driven by an exogenous random environment. We allow this environment to be quite general; it includes both continuous (graceful) degradation and degradation due to discrete shocks. For periodic inspection schemes, we compute the limiting average availability and discuss opportunities for more effective inspection policies.
Acoustic factors affecting interaural level differences for cochlear-implant users
Authors: Mayo Paul G. , Goupell Matthew J.
Published: April 2020

Bilateral cochlear-implant (BICI) listeners primarily use interaural level differences (ILDs) to localize sound in the horizontal plane. However, the ILD magnitude is altered at different frequencies and azimuths due to a combination of several acoustic phenomena such as the acoustical bright spot, acoustic axis, and microphone porting. This paper investigated the effects of BICI microphone placement on ILDs through an analysis of head-related transfer functions. At-the-canal BICI microphone placement provided both larger and more monotonic ILD-azimuth functions than behind-the-ear microphone placement. Results have implications for the fitting of clinical devices and their effect on sound localization in BICI users.
Toddlers' fast-mapping from noise-vocoded speech
Authors: Newman Rochelle S. , Morini Giovanna , Shroads Emily , Chatterjee Monita
Published: April 2020

The ability to recognize speech that is degraded spectrally is a critical skill for successfully using a cochlear implant (CI). Previous research has shown that toddlers with normal hearing can successfully recognize noise-vocoded words as long as the signal contains at least eight spectral channels [Newman and Chatterjee. (2013). J. Acoust. Soc. Am. 133(1), 483–494; Newman, Chatterjee, Morini, and Remez. (2015). J. Acoust. Soc. Am. 138(3), EL311–EL317], although they have difficulty with signals that only contain four channels of information. Young children with CIs not only need to match a degraded speech signal to a stored representation (word recognition), but they also need to create new representations (word learning), a task that is likely to be more cognitively demanding. Normal-hearing toddlers aged 34 months were tested on their ability to initially learn (fast-map) new words in noise-vocoded stimuli. While children were successful at fast-mapping new words from 16-channel noise-vocoded stimuli, they failed to do so from 8-channel noise-vocoded speech. The level of degradation imposed by 8-channel vocoding appears sufficient to disrupt fast-mapping in young children. Recent results indicate that only CI patients with high spectral resolution can benefit from more than eight active electrodes. This suggests that for many children with CIs, reduced spectral resolution may limit their acquisition of novel words.
Financing Improvements and Expansion: A Case of the Sunnyhill Health & Racquet Club
Authors: Chard Chris , McCrory Liam , Spence Kirsty
Published: April 2020

The Sunnyhill Health & Racquet Club (SHRC) is a very small, private, volunteer-run, not-for-profit club located on a swath of prime real estate in the heart of a wealthy community in Sunnyhill Township. At the behest of the club’s board, SHRC President David Wilson has been tasked with developing financing strategies to address the current (perceived) shortcomings of the club. Like he did for decades working in Post Office Square, in Boston’s Financial District, Wilson knew he had to (1) understand the current financial capacity of SHRC, (2) discern the members’ desire for financial contribution, and (3) develop financing options. Here, strategies to finance improvements to the club include debt utilization (and the necessary servicing of any debt commitments), one-time capital injections through the disposition of club property, and/or enhanced revenue generation. Developing strategies in an environment of disparate stakeholder goals provides additional challenges for Wilson.
A Contemporary Variable-Power Cycling Protocol to Discriminate Race-Specific Performance Ability
Authors: Sharma Avish P. , Bentley David J. , Mejuto Gaizka , Etxebarria Naroa
Published: April 2020

Purpose: Traditional physiological testing and monitoring tools have restricted our ability to capture parameters that best relate to cycling performance under variable-intensity race demands. This study examined the validity of a 1-h variable cycling test (VCT) to discriminate between different-performance-level cyclists. Methods: Ten male national- and 13 club-level cyclists (body mass, 67 [9] and 79 [6] kg; peak power output, 359 [43] and 362 [21] W, respectively) completed a VO2max test and two 1-h VCT protocols on 3 separate occasions. The VCT consisted of 10 × 6-min segments containing prescribed (3.5 W·kg−1) and open-ended phases. The open-ended phases consisted of 4 × 30–40 s of “recovery,” 3 × 10 s at “hard” intensity, and 3 × 6-s “sprint” with a final 10-s “all-out” effort. Results: Power output for the 6- and 10-s phases was moderately higher for the national- compared with club-level cyclists (mean [SD] 10.4 [2.0] vs 8.6 [1.6] W·kg−1, effect size; ±90% confidence limits = −0.87; ±0.65 and mean [SD] 7.5 [0.7] vs 6.2 [1.0] W·kg−1, effect size; ±90% confidence limits = −1.24; ±0.66, respectively). Power output for the final 10-s “all-out” sprint was 15.4 (1.5) for the national- versus 13.2 (1.9) W·kg−1 for club-level cyclists. Conclusion: The 1-h VCT can successfully differentiate repeat high-intensity effort performance between higher-caliber cyclists and their lower-performing counterparts.
Mitochondrial pyruvate and fatty acid flux modulate MICU1-dependent control of MCU activity
Authors: Nemani Neeharika , Dong Zhiwei , Daw Cassidy C. , Madaris Travis R. , Ramachandran Karthik , Enslow Benjamin T. , Rubannelsonkumar Cherubina S. , Shanmughapriya Santhanam , Mallireddigari Varshini , Maity Soumya , SinghMalla Pragya , Natarajanseenivasan Kalimuthusamy , Hooper Robert , Shannon Christopher E. , Tourtellotte Warren G. , Singh Brij B. , Reeves W. Brian , Sharma Kumar , Norton Luke , Srikantan Subramanya , Soboloff Jonathan , Madesh Muniswamy
Published: April 2020

Nutrient stress triggers transcriptional changes that limit Ca
2+
influx into mitochondria through the MCU.
Blocking tau propagation
Authors: Foley John F.
Published: April 2020

Knockdown of the receptor LRP1 in mice reduces the spread of the protein tau between neurons.
Reviving the “Moore Swab”: a Classic Environmental Surveillance Tool Involving Filtration of Flowing Surface Water and Sewage Water To Recover Typhoidal
Salmonella
Bacteria
Authors: Sikorski Michael J. , Levine Myron M.
Published: April 2020

The “Moore swab” is a classic environmental surveillance tool whereby a gauze pad tied with string is suspended in flowing water or wastewater contaminated with human feces and harboring enteric pathogens that pose a human health threat. In contrast to single volume “grab” samples, Moore swabs act as continuous filters to “trap” microorganisms, which are subsequently isolated and confirmed using appropriate laboratory methods. Continuous filtration is valuable for the isolation of transiently present pathogens such as human-restricted
Salmonella enterica
serovars Typhi and Paratyphi A and B.
Performance of a Modified Two-Tiered Testing Enzyme Immunoassay Algorithm for Serologic Diagnosis of Lyme Disease in Nova Scotia
Authors: Davis Ian R. C. , McNeil Shelly A. , Allen Wanda , MacKinnon-Cameron Donna , Lindsay L. Robbin , Bernat Katarina , Dibernardo Antonia , LeBlanc Jason J. , Hatchette Todd F.
Published: April 2020

Compared to the standard two-tiered testing (STTT) algorithm for Lyme disease serology using an enzyme immunoassay (EIA) followed by Western blotting, data from the United States suggest that a modified two-tiered testing (MTTT) algorithm employing two EIAs has improved sensitivity to detect early localized
Borrelia burgdorferi
infections without compromising specificity. From 2011 to 2014, in the Canadian province of Nova Scotia, where Lyme disease is hyperendemic, sera submitted for Lyme disease testing were subjected to a whole-cell EIA, followed by C6 EIA and subsequently IgM and/or IgG immunoblots on sera with EIA-positive or equivocal results.
Defining high probability when making a diagnosis of asthma in primary care: mixed-methods consensus workshop
Authors: Daines Luke , Lewis Steff , Schneider Antonius , Sheikh Aziz , Pinnock Hilary
Published: April 2020

Objective

Making the diagnosis of asthma is challenging. Guidelines recommend that clinicians identify a group at ‘high probability’ of asthma. High probability, however, is not numerically defined giving rise to uncertainty. The aim of this work was to build consensus on what constitutes a high probability of asthma in primary care. High probability was defined as the probability threshold at which there is enough information to make a firm diagnosis of asthma, and a subsequent negative test would not alter that opinion (assumed to be a false negative).

Design

Mixed-methods study.

Setting

A consensus workshop using modified nominal group technique was held during an international respiratory conference.

Participants

International conference attendees eligible if they had knowledge/experience of working in primary care, respiratory medicine and spoke English.

Methods

Participants took part in facilitated discussions and voted over three rounds on what constituted a high probability of asthma diagnosis. The workshop was audio-recorded, transcribed and qualitatively analysed.

Results

Based on final votes, the mean value for a high probability of asthma in primary care was 75% (SD 7.6), representing a perceived trade-off between limiting the number of false positives (more likely if a lower threshold was used) and pragmatism on the basis that first-line preventive therapies (ie, low-dose inhaled corticosteroids) are relatively low risk. The need to review response to treatment was strongly emphasised for detecting non-responders and reviewing the diagnosis.

Conclusion

A consensus probability of 75% was the threshold at which the primary care participants in this workshop felt confident to establish the diagnosis of asthma, albeit with the caveat that a review of treatment response was essential. Contextual factors, including availability and timing of tests and the ease with which patients could be reviewed, influenced participants’ decision making.
ALKS 4230: a novel engineered IL-2 fusion protein with an improved cellular selectivity profile for cancer immunotherapy
Authors: Lopes Jared E , Fisher Jan L , Flick Heather L , Wang Chunhua , Sun Lei , Ernstoff Marc S , Alvarez Juan C , Losey Heather C
Published: April 2020

Background

Interleukin-2 (IL-2) plays a pivotal role in immune homeostasis due to its ability to stimulate numerous lymphocyte subsets including natural killer (NK) cells, effector CD4+and CD8+T cells, and regulatory T cells (Tregs). Low concentrations of IL-2 induce signaling through the high-affinity IL-2 receptor (IL-2R) comprised of IL-2Rα, IL-2Rβ, and common γ chain (γc), preferentially expressed on Tregs. Higher concentrations of IL-2 are necessary to induce signaling through the intermediate-affinity IL-2R, composed of IL-2Rβ and γc, expressed on memory CD8+T cells and NK cells. Recombinant human IL-2 (rhIL-2) is approved for treatment of metastatic melanoma and renal cell carcinoma (RCC), but adverse events including capillary leak syndrome, potentially mediated through interaction with the high-affinity IL-2R, limit its therapeutic use. Furthermore, antitumor efficacy of IL-2 may also be limited by preferential expansion of immunosuppressive Tregs. ALKS 4230 is an engineered fusion protein comprised of a circularly-permuted IL-2 with the extracellular domain of IL-2Rα, designed to selectively activate effector lymphocytes bearing the intermediate-affinity IL-2R.

Results

ALKS 4230 was equipotent to rhIL-2 in activating human cells bearing the intermediate-affinity IL-2R, and less potent than rhIL-2 on cells bearing the high-affinity IL-2R. As observed in vitro with primary human cells from healthy donors and advanced cancer patients, ALKS 4230 induced greater activation and expansion of NK cells with reduced expansion of Tregsrelative to rhIL-2. Similarly, in mice, ALKS 4230 treatment stimulated greater expansion of NK cells and memory-phenotype CD8+T cells at doses that did not expand or activate Tregs. ALKS 4230 treatment induced significantly lower levels of proinflammatory cytokines, including tumor necrosis factor alpha, interleukin-6, and interferon gamma relative to rhIL-2. Furthermore, ALKS 4230 exhibited superior antitumor efficacy in the mouse B16F10 lung tumor model, where ALKS 4230 could be administered via multiple routes of administration and dosing schedules while achieving equivalent antitumor efficacy.

Conclusions

ALKS 4230 exhibited enhanced pharmacokinetic and selective pharmacodynamic properties resulting in both improved antitumor efficacy and lower indices of toxicity relative to rhIL-2 in mice. These data highlight the potential of ALKS 4230 as a novel cancer immunotherapy, and as such, the molecule is being evaluated clinically.
The ratio of circulating endothelin-1 to endothelin-3 associated with TIMI risk and dynamic TIMI risk score in ST elevation acute myocardial infarction
Authors: Hartopo Anggoro Budi , Puspitawati Ira , Mumpuni Hasanah
Published: April 2020

In ST segment elevation acute myocardial infarction (STEMI), the endothelin (ET) system imbalance, reflected by the circulating ET-1:ET-3 ratio has not been investigated. This study’s primary objective was to measure the circulating ET-1:ET-3 ratio and correlate it with the risk stratification for 1 year mortality of STEMI based on TIMI score. On admission, the TIMI risk score and at discharge, the dynamic TIMI risk score were calculated in 68 consecutive subjects with STEMI. Subjects with high TIMI risk score were associated with higher mean ET-1 level and ET-1:ET-3 ratio. The ET-1:ET-3 ratio more accurately predicted the high on admission TIMI risk score than the ET-1 level. Subjects with high dynamic TIMI risk score were associated with higher mean ET-1 level and ET-1:ET-3 ratio. The ET-1:ET-3 ratio more accurately predicted the high at discharge dynamic TIMI risk score than ET-1 level. From multivariable analysis, the ET-1:ET-3 ratio was not independently associated with high on admission TIMI risk score but independently predicted high at discharge dynamic TIMI risk score (odds ratio = 9.186, p = 0.018). In conclusion, combining the ET-1 and ET-3 levels into the ET-1:ET-3 ratio provided a prognostic value by independently predicting the increased risk to 1 year mortality as indicated by at discharge dynamic TIMI risk score in patients with STEMI.
Experimental investigations of the asymmetric vortex formation over a slender body of revolution at high angles of attack
Authors: Zhu Yiding
Published: April 2020

This paper describes an experimental investigation of the initial growth of flow asymmetries over a slender body of revolution at high angles of attack with natural and disturbed noses. Time-resolved particle image velocimetry (PIV) is used to investigate the flow field around the body. Flow visualization clearly shows the formation of the asymmetric vortices. Instantaneous PIV shows that the amplified asymmetric disturbances lead to Kelvin–Helmholtz instability appearing first on one side, which increases the momentum exchange crossing the layer. As a result, the separation region shrinks which creates the initial vortex asymmetry.
Surface flow modification of aerofoils for automotive racing car applications
Authors: Allarton Richard , Yao Jun , Clifford Tyler , Hitchborn Benjamin , Parker Liam J , Shaw Joshua
Published: April 2020

An aerofoil commonly used in aerospace engineering to produce lift is also employed in the motor sport industry to produce downforce for improving traction during cornering. This paper investigates aerofoil surface modification through ‘golf ball dimpling’, used to reduce flow separation behind a golf ball. The studies of other researchers have shown that this type of design can have a positive effect on improving aerofoil performance. However, no optimization information of dimple sizing is given in literature. Therefore, three types of dimpling sized at 5, 10 and 15 mm are applied to the surface of a NACA 6615 wing at 25% chord length from the leading edge in this study using Computational Fluid Dynamics (CFD) as an initial design process. Then a physical model, made through 3D printing additive manufacturing (AM), is tested at angles of attack (AoA) ranging from [Formula: see text] to [Formula: see text] and wind speed up to 30 m/s in a subsonic wind tunnel. Experimental and CFD results show that the smallest dimple size provides the most significant increase on lift to drag ratio at high AoA above [Formula: see text]. This ratio increases further with the wind speed, indicating that a high AoA wing favors down force to improve drag reduction performance.
Exploration on application of dredging thermal protection in the leading edge of the wing
Authors: Zhu Xiao-Jun , Li Feng
Published: April 2020

Aiming at the severe aerodynamic heating problem in the leading edge of the hypersonic vehicle, in order to ensure the sharp shape of the leading edge of the wing, a dredging thermal protection structure is proposed, and the built-in high-temperature heat pipe structure is used to provide thermal protection for the leading edge of the wing. By means of numerical simulation and arc wind tunnel test, the dredging thermal protection structure of the leading edge of the wing is analyzed, and the thermal protection effect of the built-in high-temperature heat pipe is obtained. The numerical results show that under certain thermal conditions, the temperature at the leading edge of the wing decreases by 304 K, and the minimum temperature of the tail increases by 130 K. The heat flow is dredged from the high-temperature zone to the low-temperature zone, and the thermal load of the leading edge of the wing is weakened. The same result can be obtained by the arc wind tunnel test, which verifies the accuracy of the numerical method and the feasibility of the dredging thermal protection structure with high-temperature heat pipe embedded in the leading edge of the wing.
Numerical simulation of flow distribution in the header of plate-fin heat exchanger
Authors: Tian Shu-Ling , Shen Ying-Ying , Li Yao , Wang Hai-Bo , Muhammad Sheryar , Si Hai-Qing
Published: April 2020

Plate-fin heat exchangers are widely used in industry at present due to their compact structure and high efficiency. However, there is a problem of flow maldistribution, resulting in poor performance of heat exchangers. The influence of the header configuration on fluid flow distribution is studied by using CFD software FLUENT. The numerical results show that the fluid flow inside the header is seriously uneven. The reliability of the numerical simulation is validated against the published results. They are found to be basically consistent within considerable error. The optimal number of the punch baffle is investigated. Various header configuration with different opening ratios have been studied under the same boundary conditions. The gross flow maldistribution parameter (S) is used to evaluate flow nonuniformity, and the flow maldistribution parameters of different schemes under different Reynolds numbers are listed and compared. The optimal header with minimum flow maldistribution parameter is obtained through the performance analysis of headers. It is found that the flow maldistribution of the improved header is significantly smaller compared with the conventional header. Hence, the efficiency of the heat exchanger is effectively enhanced. The conclusion provides a reference for the optimization design of plate-fin heat exchanger.
Phase synchronization of memristive systems by using saturation gain method
Authors: Ma Siyu , Zhou Ping , Ma Jun , Wang Chunni
Published: April 2020

A variety of electric components can be used to bridge connection to the nonlinear circuits, and continuous pumping and consumption of energy are critical for voltage balance between the output end. The realization and stability of synchronization are mainly dependent on the physical properties of coupling channel, which can be built by using different electric components such as resistor, capacitor, induction coil and even memristor. In this paper, a memristive nonlinear circuit developed from Chua circuit is presented for investigation of synchronization, and capacitor, induction coil are jointed with resistor for building artificial synapse which connects one output of two identical memristive circuits. The capacitance and inductance of the coupling channel are carefully adjusted with slight step increase to estimate the threshold of coupling intensity supporting complete synchronization. As a result, the saturation gain method applied to realize the synchronization between chaotic circuits and physical mechanism is presented.
Optical solitons of the paraxial wave dynamical model in kerr media and its applications in nonlinear optics
Authors: Arshad Muhammad , Seadawy Aly R. , Lu Dianchen , Khan Farman Ullah
Published: April 2020

The solitons and other solutions illustrate nondiffractive and nondispersive spatio-temporal localized packets of wave propagating in the media of optical Kerr. In this paper, solitons, elliptic function and other solutions of dimensionless time-dependent paraxial wave model are constructed via employing three mathematical techniques, namely, the improved simple equation technique, [Formula: see text]-expansion technique and modified extended direct algebraic technique. These wave solutions have key applications and help to understand the physical phenomena of this wave model. By giving appropriate parameter values, different types of solitons structures can be depicted graphically. Several precise solutions and computations have proved the straightforwardness, consistency and power of the these techniques.
Application of bifurcation method and rational sine-Gordon expansion method for solving 2D complex Ginzburg–Landau equation
Authors: Leta Temesgen Desta , El Achab Abdelfattah , Liu Wenjun , Ding Jian
Published: April 2020

This paper implements bifurcation method and the rational sine-Gordon expansion method to investigate the dynamical behavior of traveling wave solutions of a 2D complex Ginzburg–Landau equation. By varying the parameters, we obtained traveling wave solutions including the periodic wave solutions, solitary wave solution, kink and anti-kink wave solution and in addition by using the rational sine-Gordon expansion method, we determined bright and dark soliton which have a great contribution in the long distance telecommunication system.
The Hand as a Homunculus – A Perspective from Hand Acupuncture Therapy
Authors: Ro Du Hyun , Gong Hyun Sik
Published: April 2020

Homunculus is a term used to refer to any representation of a miniature human being. In scientific fields, the word homunculus has been used to refer to any scale model of the human body that represents physiological, psychological, or other human functions. The hand is thought as a homunculus of the body in Hand Acupuncture Therapy, a type of alternative medicine in Korea. Hand acupuncture therapists believe stimulating the hand can improve bodily health. Although there is a need for scientific evidence regarding this concept, those that perform hand acupuncture seem to recognize the importance of hand in our body.
Evolution of late Paleozoic shearing in the Cobequid Highlands: constraints on the fragmentation of the Appalachian Orogen in Nova Scotia along intra-continental shear zones
Authors: Piper David J. W. , Pe-Piper Georgia
Published: April 2020

The Cobequid Highlands of northern Nova Scotia lie at the intersection of two major dextral intra-continental shear zones which developed during closure of the Rheic Ocean and formation of Pangea. The Cobequid Shear Zone was an ENE–WSW transfer zone in a NE–SW-trending, orogen-parallel, shear system in the late Devonian–early Carboniferous (Neo-Acadian phase), in which syntectonic granite–gabbro plutons and volcanic strata <4 km thick were progressively deformed along multiple faults. In the Late Carboniferous–Permian, the Alleghanian collision of Africa with Laurentia formed the east–west-trending Minas Fault Zone, reactivating parts of the Cobequid Shear Zone. This deformation was mostly taken up on the master Cobequid–Chedabucto Fault. Deformation chronology is well constrained by the biostratigraphy of syntectonic sedimentary rocks, and by radiometrically dated igneous rocks and minerals in faults and veins. Early strike-slip faults were lubricated by magmatic heating, leading to dyke-to-pluton construction along multiple faults. During cooling, rooted gabbro was more resistant than ductile granite, thereby deflecting solid-state deformation. Neo-Acadian strike-slip displacement across the shear zone is estimated as >50 km. The location of Alleghanian deformation was influenced by the paucity of magmatism and the resistance offered by older stitching plutons.
Grain Boundary Complexion Transitions
Authors: Cantwell Patrick R. , Frolov Timofey , Rupert Timothy J. , Krause Amanda R. , Marvel Christopher J. , Rohrer Gregory S. , Rickman Jeffrey M. , Harmer Martin P.
Published: April 2020

Grain boundaries can undergo phase-like transitions, called complexion transitions, in which their structure, composition, and properties change discontinuously as temperature, bulk composition, and other parameters are varied. Grain boundary complexion transitions can lead to rapid changes in the macroscopic properties of polycrystalline metals and ceramics and are responsible for a variety of materials phenomena as diverse as activated sintering and liquid-metal embrittlement. The property changes caused by grain boundary complexion transitions can be beneficial or detrimental. Grain boundary complexion engineering exploits beneficial complexion transitions to improve the processing, properties, and performance of materials. Here, we review the thermodynamic fundamentals of grain boundary complexion transitions, highlight the strongest experimental and computationalevidence for these transitions, clarify a number of important misconceptions, discuss the advantages of grain boundary complexion engineering, and summarize existing research challenges.
Topological Properties of Nanostar Dendrimer and Smart Polymer
Authors: Rashid Muhammad Aamer , Ahmad Sarfraz , Cancan Murat , Muhammad Mehwish Hussain
Published: April 2020

The nanostar dendrimers are a piece of another gathering of macromolecules that seem, by all accounts, to be photon pipes simply like counterfeit reception apparatuses. In addition, nanostar dendrimers are one of the fundamental stuffs of nanobiotechnology. The smart polymers are large-scale particles that show an emotional physioconcoction change because of little changes in their condition, for example, temperature, pH, light, attractive field, and ionic variables. A topological record of a graph G is a numeric quantity notorious with G which portrays subatomic diagram G. In this paper, we decide first and second Zagreb indices, hyper-Zagreb index, first multiple Zagreb index, second numerous Zagreb index, and Zagreb polynomials for nanostar dendrimer and smart polymer.
Effect of Reverse Polarisation of an Electromagnetic Field on the Performance of a Silicon PV Cell
Authors: Saria Mamoudou , Zouma Bernard , Korgo Bruno , Bokoyo Barandja Vinci de Dieu , Zoungrana Martial , Zerbo Issa , Bathiebo Dieudonné Joseph
Published: April 2020

This paper investigated, by one‐dimensional modelling, the effects of reverse polarisation of an electromagnetic field, generated by an amplitude modulation radio antenna, on the efficiency of a silicon PV cell. Through a simulation, the effects of both the incidence angle and the electromagnetic field magnitude on the power output of the PV cell are analyzed. The power output curves against the junction dynamic velocity are used to find the junction dynamic velocity at the equilibrium, the maximum power output, and the efficiency of the PV cell. The results have shown that the presence of important electromagnetic fields in the neighborhood of a silicon PV cell decreases its performance.
Metformin Ameliorates Aβ Pathology by Insulin-Degrading Enzyme in a Transgenic Mouse Model of Alzheimer’s Disease
Authors: Lu Xin-Yi , Huang Shun , Chen Qu-Bo , Zhang Dapeng , Li Wanyan , Ao Ran , Leung Feona Chung-Yin , Zhang Zhimin , Huang Jisheng , Tang Ying , Zhang Shi-Jie
Published: April 2020

Alzheimer’s disease (AD) is the most common neurodegenerative disease. The accumulation of amyloid beta (Aβ) is the main pathology of AD. Metformin, a well-known antidiabetic drug, has been reported to have AD-protective effect. However, the mechanism is still unclear. In this study, we tried to figure out whether metformin could activate insulin-degrading enzyme (IDE) to ameliorate Aβ-induced pathology. Morris water maze and Y-maze results indicated that metformin could improve the learning and memory ability in APPswe/PS1dE9 (APP/PS1) transgenic mice. 18F-FDG PET-CT result showed that metformin could ameliorate the neural dysfunction in APP/PS1 transgenic mice. PCR analysis showed that metformin could effectively improve the mRNA expression level of nerve and synapse-related genes (Syp, Ngf, and Bdnf) in the brain. Metformin decreased oxidative stress (malondialdehyde and superoxide dismutase) and neuroinflammation (IL-1β and IL-6) in APP/PS1 mice. In addition, metformin obviously reduced the Aβ level in the brain of APP/PS1 mice. Metformin did not affect the enzyme activities and mRNA expression levels of Aβ-related secretases (ADAM10, BACE1, and PS1). Meanwhile, metformin also did not affect the mRNA expression levels of Aβ-related transporters (LRP1 and RAGE). Metformin increased the protein levels of p-AMPK and IDE in the brain of APP/PS1 mice, which might be the key mechanism of metformin on AD. In conclusion, the well-known antidiabetic drug, metformin, could be a promising drug for AD treatment.
Reaction Kinetics of Sodium Bentonite with Different Acid Systems: An Experimental Study
Authors: Li Yang , Ni Xiaoming , Zhao Zheng , Yang Cixiang , Li Zhongcheng
Published: April 2020

Discovering the characteristics of the reaction kinetics of acid systems (hydrogen fluoride (HF), hydrochloric acid (HCl), and CH3COOH) at different concentrations with sodium bentonite can provide experimental support for optimising formulations used in removing plugs through acidification. By utilising a spectrophotometer and acid-base titration, changes in contents of Si, Al, and H+ concentration when sodium bentonite reacted with different acid systems (HF, HF, HCl, and HF and CH3COOH) at different concentrations (5%, 10%, and 15%) for different reaction times (1, 2, 4, 8, 12, and 24 h) at 45°C were measured. Based on this, a reaction kinetics model of H+ was fitted and reaction mechanisms of HF with sodium bentonite after adding HCl and CH3COOH were analysed. The results demonstrated that the rate of dissolution of Al was high and the reaction reached equilibrium in 1 h. Si showed a fast dissolution rate in the acid solution containing HF. In an HCl + HF + CH3COOH acid system, at a concentration of 15%, the greatest dissolution occurred, with a more stable dissolution rate and longer reaction time. Among the three acids tested, it was HF that mainly reacted with sodium bentonite, while the other two acids had weak reactions therewith. In the acid system containing HF, HF molecules reacted with sodium bentonite, rather than other forms, such as H+, F−, and HF2−. The addition of HCl could promote the reaction, while CH3COOH inhibited the reaction. The research results provide experimental support for optimising the formulation of such acid solutions.
A Privacy-Preserving Trajectory Publication Method Based on Secure Start-Points and End-Points
Authors: Zhao Yannian , Luo Yonglong , Yu Qingying , Hu Zhaoyan
Published: April 2020

By judging whether the start-point and end-point of a trajectory conform to the user’s behavioral habits, an attacker who possesses background knowledge can breach the anonymous trajectory. Traditional trajectory privacy preservation schemes often generate an anonymous set of trajectories without considering the security of the trajectory start- and end-points. To address this problem, this paper proposes a privacy-preserving trajectory publication method based on generating secure start- and end-points. First, a candidate set containing a secure start-point and end-point is generated according to the user’s habits. Second, k−1 anonymous trajectories are generated bidirectionally according to that secure candidate set. Finally, accessibility corrections are made for each anonymous trajectory. This method integrates features such as local geographic reachability and trajectory similarity when generating an anonymized set of trajectories. This provides users with privacy preservation at the k-anonymity level, without relying on the trusted third parties and with low algorithm complexity. Compared with existing methods such as trajectory rotation and unidirectional generation, theoretical analysis and experimental results on the datasets of real trajectories show that the anonymous trajectories generated by the proposed method can ensure the security of trajectory privacy while maintaining a higher trajectory similarity.
Plant Extracts for Sleep Disturbances: A Systematic Review
Authors: Guadagna S. , Barattini D. F. , Rosu S. , Ferini-Strambi L.
Published: April 2020

Background. Sleep complaints are common health issues in the general population. These conditions are associated with poorer physical and psychological activity, and they may have important social, economic, and personal consequences. In the last years, several food supplements with different plant extracts have been developed and are currently taken for improving sleep. Study Objectives. The aim of this study is to systematically review recent literature on oral plant extracts acting on sleep disorders distinguishing their action on the different symptoms of sleep complaints: difficulty in initiating or maintaining sleep, waking up too early, and quality of sleep. Methods. We searched the PubMed database up to 05/03/2020 based on data from randomized, double‐blind, placebo‐controlled trials, noncontrolled trials, and cohort studies conducted in children and adult subjects. The search words used contained the following terms: oral food supplement and sleep disorders and the like. The most studied compounds were further analyzed with a second search using the following terms: name of the compound and sleep disorders. We selected 7 emerging compounds and 38 relevant reports. Results. Although nutraceutical natural products have been used for sleep empirically, there is a scarcity of evidence on the efficacy of each product in clinical studies. Valerian and lavender were the most frequently studied plant extracts, and their use has been associated (with conflicting results) with anxiolytic effects and improvements in quality and duration of sleep. Conclusions. Sleep aids based on plant extracts are generally safe and well tolerated by the population. More high‐quality research is needed to confirm the effectiveness of food supplements containing plant extracts in sleep complaints; in particular, it would be interesting to evaluate the association between plant extracts and sleep hygiene guidelines and to identify the optimal products to be used in a specific symptom of sleep complaint, giving more appropriate tools to the medical doctor.
Engineering Quantum Dot (Cadmium Sulfide) on Antibodies for Fluoroimmunoassays
Authors: Lodhi Madeeha Shahzad , Samra Zahoor Qadir
Published: April 2020

Antibodies are good escorts for a therapeutic and diagnostic tool against many diseases as well as for targeting drug delivery and in immunohistochemistry. Cysteine-capped cadmium sulfide (quantum dot) nanoparticles have wide applications in immunohistochemistry due to their unique physical, chemical, and fluorescent properties. In this study, polyclonal antibodies against transferrin (as ligand), doxorubicin (anticancer drug), and H. pylori (cancer-causing agent) were developed in rabbits and purified. Purified antibodies were labeled with cadmium sulfide (CdS) quantum dot (QD) and used as a fluorescent-labeled marker for one-step identification in diagnosis and therapeutics. Cysteine-capped CdS QDs were synthesized in the presence of taurine (antioxidant) and characterized by FTIR, VSM, DLS, and TEM. CdS nanoparticles are monodisperse with a narrow size range below 7 nm and showed an increase of almost 30 nm after conjugation to IgG. The binding of QD-labeled antibodies was observed and confirmed by binding on MDA-MB 231 cancer cells, mouse liver tissue, mouse tumor tissue, and H. pylori under a fluorescent microscope. QD-labeled antibodies gave sharp fluorescence after binding with their respective targets. Intensity of fluorescence with quantum dot enhances many folds as compared to that of traditional fluorescent-labeled compounds. Experiments are underway to target transferrin and doxorubicin and to analyze the role of H. pylori in a mouse model of gastric cancer.