bluuebunny/crossref_metadata_2025 huggingface dataset:
Computations of the Numerical Solutions of Higher Class of Navier-Stokes Equations: 2D Newtonian Fluid Flow
Authors: Surana K. S. , Nayak H. Vijayendra
Published: April 2020

This paper presents formulations, computations, investigations and consequences of the various aspects of the numerical solutions of classes C00 and C11 of the two dimensional Navier-Stokes equations in primitive variables u, v, p, τxx, τxy and τyy for incompressible, isothermal and laminar Newtonian fluid flows using p-version Least Squares Finite Element Formulations (LSFEF). The stick-slip problem is used as a model problem in all investigations since this model problem is typical of many other flow situations like contraction, expansion etc. The major thrust of the work presented is to attempt to resolve the local behavior of the solutions in the immediate vicinity of the stick-slip point.

The investigations reveal the following: a) The manner in which the stresses are non-dimensionalized in the governing differential equations (GDEs) influences the performance of the iterative procedure of solving non-linear algebraic equations and thus, computational efficiency. b) Solutions of the class C00 are always the wrong class of solutions and thus are always spurious. c) In the flow domains, containing sharp gradients of dependent variables, conservation of mass is difficult to achieve specially at lower p-levels. d) C11 solutions of the Navier-Stokes equations are in conformity with the continuity considerations in the GDEs. e) An augmented form of the Navier-Stokes equations is proposed that always ensures conservation of mass regardless of mesh, p-levels and the nature of the solution gradients. This approach yields the most desired class of C11 solutions. f) It is mathematically established and numerically demonstrated using stick-slip problem that τij are in fact zero at the stick-slip point and the peak values of τxx and τyy must occur, and in fact do, past the stick-slip point in the free field and that peak values of τxy must occur before the stick-slip point on the no-slip boundary. Thus, there is no singularity of τij in the stick-slip problem at the stick-slip point. A significant finding is that imposition of symmetry boundary condition (necessary based on physics) at the stick-slip point even in C11 interpolations is not possible without deteriorating τij behavior in the vicinity of the stick-slip point. However, with the boundary condition, the peak of τxy does occur before the stick-slip point, while the locations of τxx and τyy remain past the stick-slip point in the free field. h) A significant feature of our research work is that we utilize straightforward p-version LSFEF with C00 and C11 type interpolation without linearizing GDEs and that SUPG, SUPG/DC, SUPG/DC/LS operators are neither needed nor used. All numerical studies are conducted and presented using three different meshes (progressively refined and graded) for two different velocities (0.01 and 100 m/s).
Solutions of Higher Class and Their Computations for Polymer Flows Using Giesekus Constitutive Model
Authors: Surana K. S. , Nayak H. Vijayendra
Published: April 2020

This paper presents formulations, computations and investigations of the solutions of classes C00 and C11 for two dimensional viscoelastic fluid flows in u, v, p, τijp, τijs with Giesekus constitutive model using p-version least squares finite element formulation (LSFEF). The main thrust of the research work presented in the paper is to employ ‘right classes of interpolations’ and the ‘best computational strategy’ 1) to obtain numerical solutions of governing differential equations (GDEs) for increasing Deborah numbers 2) to investigate the nature of the computed solutions with the aim of establishing limiting values of the flow parameters beyond which the solutions may be possible to compute, but may not be meaningful.

The investigations presented in this paper reveal the following: a) The manner in which the stresses are non-dimensionalized significantly influences the performance of the iterative procedure of solving non-linear algebraic equations. b) Solutions of the class C00 are always the wrong class of solutions of GDEs in variables u, v, p, τijp and τijs and thus spurious. c) C11 class of solutions are the right class of solutions of the GDEs in variables u, v, p, τijp and τijs. d) In the flow domains, containing sharp gradients of the dependent variables, conservation of mass is difficult to achieve at lower p-levels (worse for coarse meshes). e) An augmented form of GDEs are proposed that always ensure conservation of mass at all p-levels regardless of the mesh and the nature of the solution gradients. f) Stick-slip problem is used as a model problem. Dimensions, fluid properties and flow rates used correspond to MIT experiments [20]. We demonstrate that converged solutions are possible to compute for all flow rates reported in ref [20] and that the detailed examination of the solution characteristics reveals them to be in agreement with all the physics of the flow, g) Numerical studies with graded meshes and high p-levels presented in this paper are aimed towards establishing and demonstrating detail behavior of local as well as global nature of the computed solutions, h) Various norms are proposed and tested to judge local and global dominance of elasticity or viscous behavior i) New definitions are proposed for elongational (extensional) viscosity. The proposed definitions are more in conformity and agreement with the flow physics compared to currently use definitions j) A significant aspect and strength of our work is that we utilize straightforward p-version LSFEF with C00 and C11 type interpolations without linearizing GDEs and that SUPG, SUPG/DC, SUPG/DC/LS operators are neither needed nor used.
Inefficacy of Evaluation of Temperatures in Overdriven Steady Wave Fronts Using Thermoelastic Theory
Authors: Sano Yukio , Abe Akihisa , Yamasaki Akira
Published: April 2020

The temperature distributions in overdriven steady wave fronts in 2024 Al shocked up to 80 GPa were predicted using the thermoelastic theory (Wallace theory), where the viscous stress is neglected, and the thermoviscous theory (Sano-Abe theory). The Wallace theory was improved by applying a more exact equation to the bulk modulus. As shock loading was increased, the difference between the temperature distributions predicted using each theory was greater. This tendency of the difference was similar for shocks up to 250 GPa in Pt. Thus, temperature distributions in overdriven steady wave fronts cannot be effectively evaluated using thermoelastic theory.
A New Theoretical and Computational Framework for Computing Solution of Higher Classes With Application to Gasdynamics in Eulerian Frame of Reference
Authors: Surana K. S. , Ahmadi Ali R.
Published: April 2020

This paper presents a new computational strategy along with a computational and mathematical framework for computing non-weak numerical solutions of stationary and time dependent partial differential equations. This approach utilizes strong form of the governing differential equations (GDE) and least squares approach in constructing the integral form. This new proposed approach is applied to one dimensional transient gasdynamics equation in Eulerian frame of reference using ρ, u, T as dependent variables. The currently used finite element approaches seek convergence of a solution in a fixed order space by h, p, or hp-adaptive processes. The fundamental point of departure in the proposed approach is that we seek the convergence of the computed converged solution over the spaces of different orders containing the basis functions. With this approach, dramatically higher convergence rates than those obtained for h, p, or hp-processes are achievable and the sequence of progressively converged solutions over the spaces of progressively increasing order in fact converge to the strong solution (analytical or theoretical) of the partial differential equation. It is demonstrated using one-dimensional transient Navier-Stokes equations for compressible fluid flow in Eulerian frame of reference, that in the presence of physical diffusion and dissipation, our computed solutions have exactly the same characteristics as the strong solutions. Riemann shock tube is used as a model problem.
Theory for Estimating Temperatures in Steady Wave Fronts
Authors: Sano Yukio , Abe Akihisa
Published: April 2020

The purpose of this study is to establish an Inside Temperature (IT) method for estimating temperatures in steady wave fronts in a thermoviscous material. A fundamental assumption that the material in the wave front, was approximately in an equilibrium state was used in this method. A further assumption that heat transport was neglected was used in the ITdQ=0 method, while in the ITIM method, the work done by the thermal stress was offset by heat transport. Two irreversible thermodynamic equations for the temperature in the wave front derived were connected with the Hugoniot function and the Mie-Grüneisen equation, respectively. To verify the efficacy of the IT method, three temperature distributions were estimated qualitatively using an equation for entropy including no assumption on heat transport, that including the assumption used in the ITdQ=0 method, and that in the ITIM method. These three distributions suggested that the temperatures were overestimated by the ITdQ=0 method, while the ITIM method was effective for shock compressions where the effect of viscosity was distinguished.
Tectonic and Overpressured Zones, Gulf of Mexico
Authors: Syngaevsky Pavel E.
Published: April 2020

We observe two different events happening in a Matagorda Island area. Faults may act as a seal and enhance the shale sealing. Changes in pore pressure calculated from sonic/resistivity logs are steep, “transitional” zone is about a 100–150′ thick and almost invisible at a whole well scale. Because of such sharp changes these zones are hard to recognize on MWD, however typically one casing point required to separate it from upper normally pressured section.

Another option — fault causes partial damage, possibly through micro-fractures in shales. Shale sealing properties are decreased pore pressure in reservoir sands is lower, that in neighboring blocks. Sealing zone possess gradual changes in pore pressure with lower values that expected. Such zones are up to 2000′ thick and could be observed on MWD as well as on conventional log diagrams. Several casing points required in order to drill through such zone.

By incorporating this information into the geological model one can predict whether the fault will act as a pressure-formation liquids “semi-conductor” or as a good seal. Faults that damage the seal above overpressured zone might result in unexpected shallow overpressure and/or shallow gas. Such faults should be determined, mapped and avoid when possible from drilling.
Experimental Verification of Fractal Geometry of Tool-Chip Contact in Machining
Authors: Longstreet Amber , Raman Shivakumar
Published: April 2020

The tool-chip interface in machining often consists of sliding and sticking islands of varying geometry intertwined within each other. Preliminary experimental evidence verifying the fractal geometry of the sticking/sliding profiles is presented in this paper.
Reliability Consideration in Plutonium Storage Container
Authors: Yeh Hsiang Y. , Masudi Houshang
Published: April 2020

Plutonium storage container is a very complex structure. There are many variables that affect the structural behavior of container. It is very difficult to obtain an explicit limit state function of this structure to perform the reliability analysis. This study used several techniques for the reliability analysis of container and consequently a suitable and efficient method is recommended for the container reliability study. The reliability of container was calculated using the proposed approach and the effect of random variables in the reliability of container is also assessed.
The interplay of damping and amplitude in the nonlinear pendulum
Authors: Braza Peter A.
Published: April 2020

A highly accurate solution of the nonlinear pendulum with small initial amplitude and damping proportional to the velocity is derived using multi-time scale perturbation methods. The nonlinear pendulum has been studied extensively, but its formulation has rarely incorporated damping. This paper extends the body of traditional results by using a mathematical framework that incorporates damping to get a clear, robust solution in which the interplay of the damping and amplitude yields new physical insights into the pendulum's motion.
Games of life
Authors: Faux David A. , Shah Mayank , Knapp Christopher
Published: April 2020

Cellular automata are widely used in undergraduate physics courses to educate students in elementary programming and for project work. Cellular automata are coded with simple rules yet provide a rich if well-trodden landscape for exploring aspects of physics such as diffusion and magnetism. Mathematical games, such as the minority game or the prisoner's dilemma, are also amenable to project work with the added dimension of applications in finance, econophysics, and social physics. Conway's classical game of life is both a mathematical game and a cellular automaton. We exploit adaptations of Conway's game of life as an opportunity for undergraduate students to explore new territory within the safe haven of an easy-to-implement cellular automaton. Students may discover new “lifeforms” comprising collections of live, dead, and part-live cells, and explore the escalation of floating-point errors leading to chaos-like behavior, amongst many phenomena not observed in Conway's classical counterpart.
Analyzing the structure of basic quantum knowledge for instruction
Authors: Zuccarini Giacomo
Published: April 2020

In order to support students in the development of expertise in quantum mechanics, we asked which concepts and structures can act as organizing principles of non-relativistic theory. The research question has been addressed in a multi-step process based on the analysis of categorization studies, on a content analysis of a sample of undergraduate textbooks, and on the results of existing research on learning difficulties. The answer consists of seven concept maps, intended as models of the organizing principles of quantum knowledge needed to account for the results of measurement and time evolution. By means of these instruments, it is possible to visualize and explore the different facets of the interplay between the vector structure of the quantum states and the operator structure of the observables, and to highlight the educational significance of the relations between observables. The maps can be used by instructors as a support for helping students build a well-organized knowledge structure and by researchers as a basis for the design of investigations into student understanding. While this framework may be adapted to different approaches and interpretive stances, it provides indications in favor of a spin-first approach over a waves-first one.
Are BMI, Self-Perceptions, Motor Competence, Engagement, and Fitness Related to Physical Activity in Physical Education Lessons?
Authors: Valentini Nadia Cristina , Nobre Glauber Carvalho , de Souza Mariele Santayana , Duncan Michael J.
Published: April 2020

Background: Higher levels of actual and perceived motor competence are purported to lead to participation in physical activity (PA). Whereas considerable work has been published regarding motor and perceived competence and body mass index (BMI), much less is known about the association of these variables considering PA and engagement in physical education settings—the focus of the present study. Method: In 600 children (aged 3–10 y), PA during physical education lessons, locomotor skills, object control skills, perceived competence, and BMI (study 1) were assessed. In a subsample of 149 children, PA, engagement, and health-related fitness were assessed (study 2). Results: Structural equation model showed that in study 1, locomotor skills were the strongest variable in the early years, and object control skills were the strongest later, in explained PA. The regression analysis, in study 2, showed that BMI, object control skills, and engagement were significantly associated with PA and that appropriate motor engagement was the best predictor of PA. Conclusion: The authors extended previous research by providing evidence that motor competence varies across childhood in explaining participation in PA, and appropriate motor engagement plays a critical role in being active during lessons and was the strongest predictor of PA. BMI and self-perception were not significant in the models.
Genetic Mutations Associated with Isoniazid Resistance in Mycobacterium tuberculosis in Mongolia
Authors: Narmandakh Erdenegerel , Tumenbayar Oyuntuya , Borolzoi Tsetsegtuya , Erkhembayar Baasansuren , Boldoo Tsolmon , Dambaa Naranzul , Burneebaatar Buyankhishig , Nymadawa Naranbat , Mitarai Satoshi , Jav Sarantuya , Chiang Chen-Yuan
Published: April 2020

Globally, mutations in the
katG
gene account for the majority of isoniazid-resistant strains of
Mycobacterium tuberculosis
. Buyankhishig et al. analyzed a limited number of
Mycobacterium tuberculosis
strains in Mongolia and found that isoniazid resistance was mainly attributable to
inhA
mutations (B. Buyankhishig, T. Oyuntuya, B. Tserelmaa, J. Sarantuya, et al., Int J Mycobacteriol 1:40–44, 2012,
https://doi.org/10.1016/j.ijmyco.2012.01.007
).
LuxR Solos in the Plant Endophyte
Kosakonia
sp. Strain KO348
Authors: Mosquito Susan , Meng Xianfa , Devescovi Giulia , Bertani Iris , Geller Alexander M. , Levy Asaf , Myers Michael P. , Bez Cristina , Covaceuszach Sonia , Venturi Vittorio
Published: April 2020

Cell-cell signaling in bacteria allows a synchronized and coordinated behavior of a microbial community. LuxR solos represent a subfamily of proteins in proteobacteria which most commonly detect and respond to signals produced exogenously by other microbes or eukaryotic hosts. Here, we report that a plant-beneficial bacterial endophyte belonging to the novel genus of
Kosakonia
possesses two LuxR solos; one is involved in the detection of exogenous
N
-acyl homoserine lactone quorum sensing signals and the other in detecting a compound(s) produced by the host plant. These two
Kosakonia
LuxR solos are therefore most likely involved in interspecies and interkingdom signaling.
MicroRNA-155 Deficiency Exacerbates Trypanosoma cruzi Infection
Authors: Jha Bijay K. , Varikuti Sanjay , Seidler Gabriella R. , Volpedo Greta , Satoskar Abhay R. , McGwire Bradford S.
Published: April 2020

Chagas disease, caused by the intracellular protozoan parasiteTrypanosoma cruzi, is a public health problem affecting 6 to 8 million people, mainly in Latin America. The role of microRNAs in the pathogenesis of Chagas disease has not been well described. Here, we investigate the role of microRNA-155 (miR-155), a proinflammatory host innate immune regulator responsible for T helper type 1 and type 17 (Th1 and Th17) development and macrophage responses duringT. cruziinfection.
5-Methylcytosine RNA Modifications Promote Retrovirus Replication in an ALYREF Reader Protein-Dependent Manner
Authors: Eckwahl Matthew , Xu Ruyi , Michalkiewicz Julia , Zhang Wen , Patel Pooja , Cai Zhen , Pan Tao
Published: April 2020

Over 130 modifications have been identified in cellular RNAs, which play critical roles in many cellular processes, from modulating RNA stability to altering translation efficiency. One such modification, 5-methylcytosine, is relatively abundant in mammalian mRNAs, but its precise location and function are not well understood. In this study, we identified unexpectedly high levels of m
5
C in the murine leukemia virus RNA, precisely mapped its location, and showed that ALYREF, a reader protein that specifically recognizes m
5
C, regulates viral production. Together, our findings provide a high-resolution atlas of m
5
C in murine leukemia virus and reveal a functional role of m
5
C in viral replication.
Discrete Virus Factories Form in the Cytoplasm of Cells Coinfected with Two Replication-Competent Tagged Reporter Birnaviruses That Subsequently Coalesce over Time
Authors: Campbell Elle A. , Reddy Vishwanatha R. A. P. , Gray Alice G. , Wells Joanna , Simpson Jennifer , Skinner Michael A. , Hawes Philippa C. , Broadbent Andrew J.
Published: April 2020

Reassortment is common in viruses with segmented double-stranded RNA (dsRNA) genomes. However, these viruses typically replicate within discrete cytoplasmic virus factories (VFs) that may represent a barrier to genome mixing. We generated the first replication competent tagged reporter birnaviruses, infectious bursal disease viruses (IBDVs) containing a split GFP11 or tetracysteine (TC) tag and used the viruses to track the location and movement of IBDV VFs, in order to better understand the intracellular dynamics of VFs during a coinfection. Discrete VFs initially formed from each virus that subsequently coalesced from 10 h postinfection. We hypothesize that VF coalescence is required for the reassortment of the
Birnaviridae
. This study provides new information that adds to our understanding of dsRNA virus VF trafficking.
Host Cathelicidin Exacerbates Group BStreptococcusUrinary Tract Infection
Authors: Patras Kathryn A. , Coady Alison , Babu Priyanka , Shing Samuel R. , Ha Albert D. , Rooholfada Emma , Brandt Stephanie L. , Geriak Matthew , Gallo Richard L. , Nizet Victor
Published: April 2020

Certain populations such as diabetic individuals are at increased risk for developing urinary tract infections (UTI), although the underlying reasons for this susceptibility are not fully known. Additionally, diabetics are more likely to become infected with certain types of bacteria, such as group BStreptococcus(GBS). In this study, we find that an antimicrobial peptide called cathelicidin, which is thought to protect the bladder from infection, is ineffective in controlling GBS and alters the type of immune cells that migrate to the bladder during infection. Using a mouse model of diabetes, we observe that diabetic mice are more susceptible to GBS infection even though they also have more infiltrating immune cells and increased production of cathelicidin. Taken together, our findings identify this antimicrobial peptide as a potential contributor to increased susceptibility of diabetic individuals to GBS UTI.
Perineural invasion predicts for locoregional failure in patients with oesophageal adenocarcinoma treated with neoadjuvant chemoradiotherapy
Authors: Patel Ankur K , Pan Xueliang , Vila Diana M , Frankel Wendy L , Chen Wei , Perry Kyle A , Merritt Robert E , D'Souza Desmond M , Wuthrick Evan J , Williams Terence M
Published: April 2020

Aim

The prognostic significance of perineural invasion (PNI) in oesophageal adenocarcinoma (EAC) is unclear. We examined the association of PNI with clinical outcomes in patients treated with neoadjuvant chemoradiotherapy (nCRT) and surgery.

Methods

We performed a single institutional retrospective study. We evaluated the association of PNI with locoregional recurrence-free survival (LRFS), distant metastasis-free survival, disease-free survival (DFS) and overall survival using log-rank and Cox proportional hazard modelling.

Results

29 out of 73 patients (40%) had PNI at the time of surgery. The median follow-up was 20.1 months. The median DFS was 18.4 months for patients with PNI vs 41.3 months for patients without PNI (p<0.05). The median LRFS was 23.3 months for patients with PNI and median not reached for patients without PNI (p<0.01). In a multivariate model including age and pathological variables, PNI remained a significant independent predictor of LRFS (HR 0.20, 95% CI 0.07 to 0.60; p=0.004).

Conclusions

For patients with EAC treated with nCRT, PNI found at the time of surgery is significantly associated with worse LRFS. Our data support attempts to validate this finding and perhaps testing the role of adjuvant therapy in patients with PNI.
Determinants of cerebral radiological progression in Fabry disease
Authors: Körver Simon , Longo Maria G F , Lima Marjana R , Hollak Carla E M , El Sayed Mohamed , van Schaik Ivo N , Vedolin Leonardo , Dijkgraaf Marcel G W , Langeveld Mirjam
Published: April 2020

Background and aim

It is unclear which patients with Fabry disease (FD) are at risk for progression of white matter lesions (WMLs) and brain infarctions and whether enzyme replacement therapy (ERT) changes this risk. The aim of this study was to determine the effect of ERT and clinical characteristics on progression of WMLs and infarctions on MRI in patients with FD.

Methods

MRIs were assessed for WMLs (Fazekas scale), infarctions and basilar artery diameter (BAD). The effect of clinical characteristics (renal and cardiac involvement, cardiovascular risk factors, cardiac complications, BAD) and ERT on WML and infarction progression was evaluated using mixed models.

Results

One hundred forty-nine patients were included (median age: 39 years, 38% men, 79% classical phenotype). Median follow-up time was 7 years (range: 0–13 years) with a median number of MRIs per patient of 5 (range: 1–14), resulting in a total of 852 scans. Variables independently associated with WML and infarction progression were age, male sex and a classical phenotype. Progression of WMLs and infarctions was not affected by adding ERT to the model, neither for the whole group, nor for early treated patients. Progression was highly variable among patients which could not be explained by other known variables such as hypertension, cholesterol, atrial fibrillation and changes in kidney function, left ventricular mass or BAD.

Conclusion

Progression of WMLs and cerebral infarctions in FD is mainly related to age, sex and phenotype. Additional effects of established cardiovascular risk factors, organ involvement and treatment with ERT are probably small to negligible.
Recognition, collaboration and community: science fiction representations of robot carers inRobot & Frank,Big Hero 6andHumans
Authors: Teo Yugin
Published: April 2020

In the 2010s, a small number of science fiction films and television series exploring the theme of the robot carer and how humans respond to them were released. This paper explores three works in this regard: the filmsRobot & Frank(dir. Jake Schreier, USA 2012),Big Hero 6(dir. Don Hall/Chris Williams, USA 2014) and the television seriesHumans(UK/USA, Channel 4/AMC, 2015–2018). Examining these works with some of the ethical issues currently being discussed in the use of robot technology in care work, this paper demonstrates how they align themselves with, but also challenge some of these ideas, and ultimately direct viewers to consider their own expectations of personalised healthcare. The essay begins by examining the fears of the care industry deploying robots to replace the work of human carers, followed by a discussion of the effectiveness of robots as carers as depicted in these fictional representations, and the final section considers the social environment that these robot carers are situated in, and how the robots become a reflection of human lives and a repository of memories of affective relations. These texts suggest alternate ways of thinking about human–robot interactions and care work, advocating for a more mutually dependent and reciprocal working relationship that might lead to a better quality of care.
Comparison of intra-aneurysmal flow modification using optical flow imaging to evaluate the performance of Evolve and Pipeline flow diverting stents
Authors: Cancelliere Nicole Mariantonia , Nicholson Patrick , Radovanovic Ivan , Mendes Karla Mirella , Orru Emanuele , Krings Timo , Pereira Vitor M
Published: April 2020

Background

Flow diverting stent (FDS) devices have revolutionized the treatment of large and complex brain aneurysms, but there is still room for improvement, particularly on the flow diversion properties and technical challenges associated with stent deployment. In this study we compared flow diversion properties between the new generation Surpass Evolve (Stryker) and the Pipeline Flex (Medtronic) devices by quantitatively evaluating intra-aneurysmal flow modification.

Methods

An in vitro experimental set-up was used, consisting of four patient-specific silicone models with internal carotid aneurysms and a circulating hemodynamic simulation system with pulsatile flow. The Evolve and Pipeline stents were deployed across the neck of each aneurysm model, in a randomized fashion, for a total of eight device deployments. A 60 frames/s digital subtraction angiography run was acquired before and after placement of each FDS. An optical flow-analysis method was used to measure intra-aneurysmal flow modification induced by the stent by calculating a mean aneurysm flow amplitude (MAFA) before and after stent placement and computing a ratio.

Results

Average MAFA ratio values calculated from pre- and post-stent placement were significantly lower after deployment of the Evolve (n=4, mean=0.62±0.09) compared with the Pipeline device (n=4, mean=0.71±0.06) (p=0.03).

Conclusions

Our in vitro results show that the Evolve stent had a superior flow diversion effect compared with the Pipeline stent, which—based on clinical evidence—suggest it may promote faster aneurysm occlusion rates in patients.
Navigating a proximal loop in the radial artery and avoiding the recurrent radial artery
Authors: Dossani Rimal , Waqas Muhammad , Tso Michael K , Rajah Gary B , Smolar David E , Davies Jason M
Published: April 2020

Several anatomical variations of the radial artery have been described in the literature. Common variations include radial artery loop, recurrent branch, and anastomotic channels connecting the radial and brachial arteries. These variations can pose significant technical challenges to safe radial artery catheterization. Because radial access for neurointervention is becoming popular, appreciation of these variations and mastery of techniques for safe radial artery catheterization are of paramount importance. In this operative video,(video 1) we present a case of a 75-year-old man who underwent middle meningeal artery embolization for treatment of chronic subdural hematoma using a transradial approach. The patient was found to have a radial artery loop and a recurrent branch off the radial artery. The loop could not be negotiated with the conventional technique. We therefore used a microcatheter system with a stiff microwire to navigate and straighten the radial loop under road map guidance. The remaining procedure was performed successfully.
Optimizing the trauma resuscitation bay during the covid-19 pandemic
Authors: Livingston David Hugh , Bonne Stephanie , Morello Catherin , Fox Adam
Published: April 2020

The covid-19 global pandemic due to the SARS-CoV2 (CoV2) virus has created the need to adapt hospital workspaces and staffing models, and trauma is no exception. While the optimal configuration of a trauma resuscitation area is debatable, the space needs to be large enough to accommodate the trauma team and ancillary staff. It also needs to have ready access to supplies and equipment to quickly and easily control hemorrhage, secure an airway and initiate fluid resuscitation. Lastly, stores of personal protective equipment in the form of fluid resistant gowns, head covering, face shield, and gloves (both sterile and non-sterile) should be readily available but under strict access. As CoV2 carriers increased in our population in New Jersey, we treated each incoming trauma patient as a potentially CoV2-positive case and sought to reconfigure out trauma resuscitation area to minimize exposure of our supplies to aerosolized virus.
Effectiveness of the anaesthetic combination of tiletamine, zolazepam, ketamine and xylazine for the sterilisation of street dogs in field clinics
Authors: Landry Jami , Maza Paul
Published: April 2020

15 dogs presented to a sterilisation clinic in March 2017 for ovariohysterectomy or castration surgeries. All patients were initially injected with an anaesthetic combination of Telazol (tiletamine/zolazepam), ketamine and xylazine (TKX) intramuscularly, followed by venous catheterisation and a number of follow‐up intravenous boluses of TKX when appropriate to maintain a surgical anaesthesia. 6 dogs required redosing of the TKX drug combination. Data of monitoring anaesthesia via heart rate, respiratory rate, jaw tone, limb and muscle movement were collected. These data were used to determine timing for additional intravenous half doses of TKX for the maintenance of anaesthesia. All surgeries were successful without complications, and the anaesthetic protocol was effective at maintaining surgical anaesthesia. This case report describes a group of patients in which TKX was used as the anaesthetic protocol, with details on this previously unreported protocol such that others may be able to consider using TKX in future dog sterilisation clinics.
Multiple nutritional currencies shape pregnancy in a large herbivore
Authors: Newby J.R. , DeCesare N.J.
Published: April 2020

Nutritional condition embodies environmental conditions experienced by animals with survival and reproductive consequences. Body fat is often associated with ungulate fecundity; however, other nutritional currencies may limit fecundity. Using data from 129 moose (Alces alces (Linnaeus, 1758)) monitored over 429 moose-years, we examined the limiting role of multiple nutritional currencies on pregnancy rates while concurrently assessing the influence of age and prior reproduction. Females tended to be pregnant in successive years, suggesting differences in individual or habitat quality. However, probability of pregnancy declined with survival of calves from prior litters, indicating a reproductive cost to rearing offspring. Pregnancy was positively associated with serum iron (Fe), body fat, body mass, and serum protein. The best model predicting pregnancy included serum Fe, body fat, and age class, with serum Fe being the strongest single predictor. Moose with Fe concentrations considered deficient in cattle (Bos taurus Linnaeus, 1758) had pregnancy rates of 33%–35%, whereas 89%–91% of individuals with sufficient Fe were pregnant. We subsequently evaluated hypotheses concerning factors potentially limiting Fe concentrations, including Fe-deficient diet, chronic infection, parasitism, and malnutrition. The best supported hypothesis was energy and protein malnutrition constrained Fe stores. We conclude that subclinical anemia due to nutritional constraints can limit or indicate limits in moose fecundity.
Supersymmetric proton decay revisited
Authors: Ellis John , Evans L. , Nagata Natsumi , Olive Keith A. , Velasco-Sevilla Liliana
Published: April 2020

Encouraged by the advent of a new generation of underground detectors – JUNO, DUNE and Hyper-Kamiokande – that are projected to improve significantly on the present sensitivities to various baryon decay modes, we revisit baryon decay in the minimal supersymmetric SU(5) GUT. We discuss the phenomenological uncertainties associated with hadronic matrix elements and the value of the strong coupling $$\alpha _s$$αs – which are the most important – the weak mixing angle $$\theta _W$$θW, quark masses including one-loop renormalization effects, quark mixing and novel GUT phases that are not visible in electroweak interaction processes. We apply our analysis to a variety of CMSSM, super- and sub-GUT scenarios in which soft supersymmetry-breaking parameters are assumed to be universal at, above and below the GUT scale, respectively. In many cases, we find that the next generation of underground detectors should be able to probe models with sparticle masses that are $${{\mathcal {O}}}(10)$$O(10) TeV, beyond the reach of the LHC.
Numerical application of the nonlinear coupled constitutive relations under three-dimensional hybrid unstructured finite-volume framework
Authors: He Zhi-Qiang , Fan Guo-Chao , Jiang Zhong-Zheng
Published: April 2020

The nonlinear coupled constitutive relations (NCCR) has been studied intensively under structured finite-volume framework. For further engineering applications, it is necessary to study the potential capability of NCCR with the use of unstructured mesh. In this paper, a three-dimensional NCCR solver with hybrid unstructured techniques is developed on the basis of our in-house code. An upwind flux-splitting scheme with LU-SGS implicit time-marching scheme is employed. The accuracy of the developed NCCR solver is validated by two hypersonic cases, such as high-speed flows around 2D cylinder and 3D blunted cone tip in rarefied regimes. Computations show that the solver using hybrid unstructured techniques yields comparable good results as the structured one. Moreover, they can get solutions in better agreement with the Direct Simulation Monte Carlo (DSMC) than the NS results.
Visualization of asymmetric separation induced by lateral jet interaction on a slender body in supersonic flow
Authors: Luo Shi-Jie , Liu Yao-Feng , Liu Yu-Wei
Published: April 2020

The lateral jet interaction on a slender body in supersonic flow was investigated by numerical simulation. The spatial and surface flow characteristics induced by jet interaction were shown. As a result, when the lateral jet is not in the longitudinal symmetry plane, the jet interaction causes asymmetric separation flow of surface and space, and destroys the pressure distributions of the slender body. With different angle of attack and circumferential positions of jet, the flow characteristic of the after body for jet in asymmetry plane changes greatly. The results with and without jet interaction also show that the far-field interaction played a major role in the lateral jet interaction.
Numerical investigation of transonic buffet on supercritical airfoil considering uncertainties in wind tunnel testing
Authors: Zhu Hong-Yu , Wang Gang , Liu Yi , Zhou Ze-Kun
Published: April 2020

To improve the predictive ability of computational fluid dynamics (CFD) on the transonic buffet phenomenon, NASA SC(2)-0714 supercritical airfoil is numerically investigated by noninstructive probabilistic collocation method for uncertainty quantification. Distributions of uncertain parameters are established according to the NASA wind tunnel report. The effects of the uncertainties on lift, drag, mean pressure and root-mean square pressure are discussed. To represent the stochastic solution, the mean and standard deviation of variation of flow quantities such as lift and drag coefficients are computed. Furthermore, mean pressure distribution and root-mean square pressure distribution from the upper surface are displayed with uncertainty bounds containing 95% of all possible values. It is shown that the most sensitive part of flow to uncertain parameters is near the shock wave motion region. Comparing uncertainty bounds with experimental data, numerical results are reliable to predict the reduced frequency and mean pressure distribution. However, for root-mean square pressure distribution, numerical results are higher than the experimental data in the trailing edge region.
Aeroacoustic noise generated by flow around circular cyinder with permeable boundary
Authors: Wang Fang , Liu Qiuhong
Published: April 2020

A new integral computational formulation is presented to evaluate the noncompact noise induced by low Mach number flows. Based on Howe’s Vortex Sound Theory and wave equation of Green’s function in free space, we obtain a new integral equation by choosing a permeable boundary as the integral boundary. The flow calculation is developed with second-order CFD solvers, and noise calculation is executed with a two-step method to solve scattered sources and far field pressure. Two- and three-dimensional circular cylinders are chosen as test examples. The pressure amplitude obtained with permeable boundary agrees well with that obtained with body-fitted high-order method. Numerical results indicate that the present method is valid and efficient to calculate noncompact noise, and the permeable boundary can replace the body surface as the integral boundary.
A Review of De Quervain’s Stenosing Tenovaginitis in the Context of Smartphone Use
Authors: Morgan Samuel DJ. , Sivakumar Brahman S. , An Vincent GG. , Sevao Joshua , Graham David J.
Published: April 2020

Background: De Quervain tenosynovitis (DQT) has been associated with repetitive movements of the radial first dorsal compartment. Since 2007, smartphones have become ingrained in society. Their functionality is primarily performed by dexterity of the user’s thumb(s). The aim of this study was to review the current literature regarding the correlation between DQT and smartphone usage as a systematic review has not previously been presented.

Methods: A literature review was conducted electronically using the EMBASE, PubMed, Cochrane and MEDLINE search libraries during May of 2019. Studies eligible for inclusion were English-language studies assessing the link between mobile phone use and DQT. Included studies were required to report on focused outcomes. Only original data studies were included. Case studies, those with data sets collected prior to 2007, foreign language research were excluded.

Results: A positive Finkelstein’s result within the cohorts was found in a mean of 51.54% of participants. Odds ratios (OR) of 1.5 to 2.3 were found with increasing frequency of text messages and DQT. Females were found to have a higher frequency of text messages daily. Internet browsing and gaming on mobile phones were associated with an OR of 2.21 and 2.61 respectively. DQT associated pain correlated to a mild disruption in daily tasks. On a visual analogue scale, this pain was represented as a 4 out of 10.

Conclusions: In conclusion, there appears to be a linear association between frequency of text messages and incidence of DQT. Additionally, there is an association between DQT pain and a mild disruption to daily activities other than mobile phone use.
Timing of Surgery for Pediatric Supracondylar Humerus Fractures and Early Postoperative Results
Authors: Suganuma Seigo , Tada Kaoru , Yasutake Hidetoshi , Horii Takeshi , Takata Munetomo , Shimanuki Keito , Tsuji Daiyu , Takagawa Shingo , Asano Yohei , Tsuchiya Hiroyuki
Published: April 2020

Background: Pediatric supracondylar humerus fracture (PSHF) is one of the most common fractures of the elbow seen among boys aged between 5 and 7 years. The timing of surgical treatment for this type of fracture is still controversial. Thus, we aimed to investigate whether the timing of surgery for PSHFs affects the incidence of early postoperative complications and reduction of PSHFs.

Methods: We retrospectively reviewed the medical records of PSHF patients who underwent surgery at our hospital between January 2007 and March 2019. We classified patients who underwent surgery within 12 h and more than 12 h after the fracture as the early and delayed groups, respectively. The outcome measures compared between the two groups were the incidence of postoperative early complications such as neurological deficits, including iatrogenic ulnar nerve injury, vascular compromise, compartment syndrome, K-wire migration, and unplanned returns to the operating room. We also examined surgical time, reduction procedure, and perioperative radiographic parameters.

Results: There was no significant difference in the incidence of early complications between the early and delayed groups for either modified Gartland type II or type III fractures. There was also no significant difference in surgical time, reduction procedure, or perioperative radiographic parameters between the two groups.

Conclusions: Delayed surgery was not associated with an increased rate of postoperative early complications in either type II or type III fractures. The timing of surgery does not affect the difficulty or quality of reduction.
Entrapment of the Median Nerve after Elastic Intramedullary Nailing of a Pediatric Forearm Fracture
Authors: Van Royen Kjell , Berghs Bart
Published: April 2020

Closed reduction and fixation with elastic intramedullary nails is a popular technique to treat displaced pediatric forearm fractures and has yielded good functional results. Postoperative neurological symptoms can be due to neuropraxia and expectative treatment has been advised for 3 months until further investigation is necessary. We present a case of an 11-year-old boy that presented with median nerve palsy 2 months after a displaced forearm fracture treated with elastic intramedullary nails. Ultrasound and nerve conduction study confirmed the presence of a median nerve entrapped in the callus of the radial fracture. Surgical exploration demonstrated that the nerve was twisted around the intramedullary device. After neurolysis and surgical repair the patient finally recovered 2 years after the operation. This case highlights the possibility of median nerve entrapment after reduction with elastic intramedullary nails. Symptoms should be recognized early, and urgent surgical exploration is needed to prevent irreversible damage.
FDP Avulsion Injury Due to Enchondroma: A Unique Surgical Approach
Authors: Moura Francisco , Salibi Andrej , Mishra Anuj
Published: April 2020

Flexor Digitorum Profundus avulsion injury associated with an enchondroma at the level of the distal phalanx is extremely rare. There have been few cases reported to date and most have been surgically managed using a screw and/or Bunnell pull-out wire technique with or without bone grafting. We describe the first case using a simple interosseus fixation technique for the reattachment of FDP tendon without bone grafting. The patient made an excellent post-operative recovery. This technique is a simple, effective, patient-friendly and internalised solution which, in addition, may prevent the need for bone grafting.
A contribution to the petrophysical knowledge of the Lourinhã Formation as an analogue for the Statfjord Formation in the North Sea oil and gas fields
Authors: Ludovico-Marques Marco
Published: April 2020

The Lourinhã Formation in the western region of Portugal is an analogue for the Statfjord Formation in the oil and gas fields of the Norwegian Northern North Sea. This petrophysics study encompasses a specific sandstone variety (M variety) of the Lourinhã Formation. This lithic arkose shows an average value of effective porosity of 18.5% and a permeability range of 20–30 mD, and is representative of the distribution range in the petrophysics models of the reservoirs of the Statfjord Formation. The petrographical, physical and mechanical characterization of the M variety sandstone is compared with the main features of the oil- and gas-producing sandstones of the Statfjord Formation in a reference well in the Norwegian Northern North Sea. Efficient enhanced oil recovery (EOR) projects in the oil and gas fields of the Norwegian Gullfaks hub are always needed, and this study intends to provide a contribution to that endeavour.
Excited-State Imaging of Single Particles on the Subnanometer Scale
Authors: Wallum Alison , Nguyen Huy A. , Gruebele Martin
Published: April 2020

At the intersection of spectroscopy and microscopy lie techniques that are capable of providing subnanometer imaging of excited states of individual molecules or nanoparticles. Such approaches are particularly important for imaging macromolecules or nanoparticles large enough to have a high probability of containing a defect. These inevitable defects often control properties and function despite an otherwise ideal structure. We discuss real-space imaging techniques such as using scanning tunneling microscopy tips to enhance optical measurements and electron energy-loss spectroscopy in a scanning transmission electron microscope, which is based on focused electron beams to obtain high-resolution spatial information on excited states. The outlook for these methods is bright, as they will provide critical information for the characterization and improvement of energy-switching, electron-switching, and energy-harvesting materials.