Total hip arthroplasty in Cambodia – Our experience of two hundred and fifty six consecutive total hip arthroplasties in a low-income country & the challenge of service delivery in this setting

The Children's Surgical Centre has performed 256 THAs since 2007, We aim to assess the outcome of arthroplasty in a LMIC. Primary outcome: all cause of re-operation, Secondary outcome: any other complication. A retrospective review of all consecutive THA since 2007 was conducted. Electronic and physical case notes were reviewed. Statistical analysis was performed using MedCalc. 256 THA. Mean age: 43, gender M2:1F. Common pathologies include (1) AVN (44%), (2) OA (11%) and (3) DDH (11%). Revision rate 13%. Time to revision was 2.8 years (0–9). Common revision reasons: (1) stem fracture (5.8%), (2) aseptic loosening (4.8%) and (3) infection (2.7%). Complications were identified in 85 patients (33.2%). Common complications included (1) aseptic loosening (10.5%) (2) stem fracture (5.8%) and (3) dislocation (5.8%). Patients at CSC benefit from THA, the complication rates at CSC are declining suggesting the apex of the ‘learning curve’ has passed. Cheap poorly manufactured implants continue to cause catastrophic failure.

Pressure and temperature predictions of Al2O3/water nanofluid flow in a porous pipe for different nanoparticles volume fractions: combination of CFD and ACOFIS

Artificial intelligence (AI) techniques have illustrated significant roles in finding general patterns of CFD (Computational fluid dynamics) results. This study is conducted to develop combination of the ant colony optimization (ACO) algorithm with the fuzzy inference system (ACOFIS) for learning the CFD results of a physical case study. This binary join of the ACOFIS and CFD was used for pressure and temperature predictions of Al2O3/water nanofluid flow in a heated porous pipe. The intelligence of ACOFIS is investigated for different input numbers and pheromone effects, as the ant colony tuning parameter. The results showed that the intelligence of the ACOFIS could be found for three inputs (x and y nodes coordinates and nanoparticles fraction) and the pheromone effect of 0.1. At the system intelligence, the ACOFIS could predict the pressure and temperature of the nanofluid on any values of the nanoparticles fraction between 0.5 and 2%. Comparing the ANFIS and the ACOFIS, it was shown that both methods could reach the same accuracy in predictions of the nanofluid pressure and temperature. The root mean square error (RMSE) of the ACOFIS (~ 1.3) was a little more than that of the ANFIS (~ 0.03), while the total process time of the ANFIS (~ 213 s) was a bit more than that of the ACOFIS (~ 198 s). The AI algorithms process time (less than 4 min) shows their ability in the reduction of CFD modeling calculations and expenses.

Tall Buildings in Dubai—Converting Architecture into Reality

In just over two decades, Dubai has transformed from a desert served by a single port to a flourishing metropolis. Dubai alone is the home to 20% of the world’s tallest 50 buildings. This transformation brings new challenges to the city during construction and post completion. The surrounding areas will be affected by these skyscrapers from transportation, traffic constraints, parking, power and water consumption and other factors. The cost of building a skyscraper remains the major obstacle with the need to source out new materials other than steel and concrete. Also, moving people around efficiently in super tall buildings is another challenge for engineers keeping in mind the unique designs that architects are looking after. Once all design aspects are concluded and approved by different stakeholders, it will move on to the next phase which is construction, that is called: Reality.Construction realization is the focus of this paper. It will discuss the actual facts and surprises which will be encountered during the transformation of the design into shop drawings and tangible concrete. A physical case study from a busy district in the city of Dubai is the main focus of this study along with the core challenges and obstacles faced the team during the execution phase. Also, this review will debate couple of design elements that were considered as a design feature then developed to be a real construction challenge.Originality/value: the paper will focus on a case study of a high-end skyscrapers designed and built in the city of Dubai in a dense area and the challenges faced by the team during construction. These challenges are beneficial to understand since they will help architects and designers to take into consideration during their studies.

An Avant-Garde Handling of Temporal-Spatial Fractional Physical Models

In the present study, we dilate the differential transform scheme to develop a reliable scheme for studying analytically the mutual impact of temporal and spatial fractional derivatives in Caputo’s sense. We also provide a mathematical framework for the transformed equations of some fundamental functional forms in fractal 2-dimensional space. To demonstrate the effectiveness of our proposed scheme, we first provide an elegant scheme to estimate the (mixed-higher) Caputo-fractional derivatives, and then we give an analytical treatment for several (non)linear physical case studies in fractal 2-dimensional space. The study concluded that the proposed scheme is very efficacious and convenient in extracting solutions for wide physical applications endowed with two different memory parameters as well as in approximating fractional derivatives.

Quasi-Linear Buildup of Coulomb Integrals via the Coupling Strength Parameter in the Non-Relativistic Electronic Schrödinger Equation

The non-relativistic electronic Hamiltonian, Hkin+Hne+aHee, is linear in coupling strength parameter (a), but its eigenvalues (electronic energies) have only quasi-linear dependence on it. Detailed analysis is given on the participation of electron-electron repulsion energy (Vee) in total electronic energy (Etotal electr,k) in addition to the wellknown virial theorem and standard algorithm for vee(a=1)=Vee calculated during the standard- and post HF-SCF routines. Using a particular modification in the SCF part of the Gaussian package, we have analyzed the ground state solutions via the parameter “a”. Technically, with a single line in the SCF algorithm, operator was changed as 1/rij-> a/rij with input “a”. The most important findings are, 1, vee(a) is quasi-linear function of “a”, 2, the extension of 1st Hohenberg-Kohn theorem (PSI0(a=1) <=> Hne <=> Y0(a=0)) and its consequences in relation to “a”. The latter allows an algebraic transfer from the simpler solution of case a=0 (where the single Slater determinant Y0 is the accurate form) to the physical case a=1. Moreover, we have generalized the emblematic Hund’s rule, virial-, Hohenberg-Kohn- and Koopmans theorems in relation to the coupling strength parameter.

Quasi-Linear Buildup of Coulomb Integrals via the Coupling Strength Parameter in the Non-Relativistic Electronic Schrödinger Equation

The non-relativistic electronic Hamiltonian, Hkin+Hne+aHee, is linear in coupling strength parameter (a), but its eigenvalues (electronic energies) have only quasi-linear dependence on it. Detailed analysis is given on the participation of electron-electron repulsion energy (Vee) in total electronic energy (Etotal electr,k) in addition to the wellknown virial theorem and standard algorithm for vee(a=1)=Vee calculated during the standard- and post HF-SCF routines. Using a particular modification in the SCF part of the Gaussian package, we have analyzed the ground state solutions via the parameter “a”. Technically, with a single line in the SCF algorithm, operator was changed as 1/rij-> a/rij with input “a”. The most important findings are, 1, vee(a) is quasi-linear function of “a”, 2, the extension of 1st Hohenberg-Kohn theorem (PSI0(a=1) <=> Hne <=> Y0(a=0)) and its consequences in relation to “a”. The latter allows an algebraic transfer from the simpler solution of case a=0 (where the single Slater determinant Y0 is the accurate form) to the physical case a=1. Moreover, we have generalized the emblematic Hund’s rule, virial-, Hohenberg-Kohn- and Koopmans theorems in relation to the coupling strength parameter.

Correlation functions of three-dimensional Yang-Mills theory from the FRG

We compute correlation functions of three-dimensional Landau-gauge Yang-Mills theory with the Functional Renormalisation Group. Starting from the classical action as only input, we calculate the non-perturbative ghost and gluon propagators as well as the momentum-dependent ghost-gluon, three-gluon, and four-gluon vertices in a comprehensive truncation scheme. Compared to the physical case of four spacetime dimensions, we need more sophisticated truncations due to significant contributions from non-classical tensor structures. In particular, we apply a special technique to compute the tadpole diagrams of the propagator equations, which captures also all perturbative two-loop effects, and compare our correlators with lattice and Dyson-Schwinger results.

Theoretical aspects of antimatter and gravity

In this short contribution, I review the physical case of studying the gravitational properties of antimatter from a theoretical perspective. I first discuss which elements are desirable for any theory where the long-range interactions between matter and antimatter differ from those of matter with itself. Afterwards I describe the standard way to hide the effects of new forces in matter–matter interactions which still allows one to generate ponderable matter–antimatter interactions. Finally, I comment on some recent ideas and propose some possible future directions. This article is part of the Theo Murphy meeting issue ‘Antiproton physics in the ELENA era’.

Generalization of Brillouin theorem for the non-relativistic electronic Schrödinger equation in relation to coupling strength parameter, and its consequences in single determinant basis sets for configuration interactions

<p> The Brillouin theorem has been generalized for the extended non-relativistic electronic Hamiltonian (H_Ñ+ H_ne+ aH_ee) in relation to coupling strength parameter (a), as well as for the configuration interactions (CI) formalism in this respect. For a computation support, we have made a particular modification of the SCF part in the Gaussian package: essentially a single line was changed in an SCF algorithm, wherein the operator r_ij^-1 was overwritten as r_ij^-1 ® ar_ij^-1, and “a” was used as input. The case a=0 generates an orto-normalized set of Slater determinants which can be used as a basis set for CI calculations for the interesting physical case a=1, removing the known restriction by Brillouin theorem with this trick. The latter opens a door from the theoretically interesting subject of this work toward practice. </p>

Generalization of Brillouin theorem for the non-relativistic electronic Schrödinger equation in relation to coupling strength parameter, and its consequences in single determinant basis sets for configuration interactions

<p> The Brillouin theorem has been generalized for the extended non-relativistic electronic Hamiltonian (H_Ñ+ H_ne+ aH_ee) in relation to coupling strength parameter (a), as well as for the configuration interactions (CI) formalism in this respect. For a computation support, we have made a particular modification of the SCF part in the Gaussian package: essentially a single line was changed in an SCF algorithm, wherein the operator r_ij^-1 was overwritten as r_ij^-1 ® ar_ij^-1, and “a” was used as input. The case a=0 generates an orto-normalized set of Slater determinants which can be used as a basis set for CI calculations for the interesting physical case a=1, removing the known restriction by Brillouin theorem with this trick. The latter opens a door from the theoretically interesting subject of this work toward practice. </p>