Acetabular Migration of Lag Screw of Intramedullary Nail Used as Treatment for Intertrochanteric Fracture. Case Study

Most trochanteric fractures of the femur are classified as low-energy fractures as they are seen in people with decreased mechanical properties of bone tissue. The treatment is assumed to provide biomechanical fixation with the possibility of dynamization between bony fragments to stimulate the biological processes of bone union. The aim of the study was to analyze a complication presenting as migration of the cervical screw of an intra­medullary nail towards the hip joint acetabulum and present the therapeutic management of this complication. The case report concerned a 74-year-old patient with an AO/OTA type 31 A2.2 fracture of the trochanteric massif of the right femur treated with the Gamma3 intramedullary nail. An assessment of changes over time of the radiological appearances on A-P images after the surgery showed migration of the cervical screw towards the acetabulum and displacement of the major trochanter fracture. Extensive destruction of the acetabular fossa made biologic restorative treatment impossible. A total hip joint prosthesis with a modular stem and MDM articulation was implan­ted and the trochanter was fixed with a "hook" plate with a "cable system". The postoperative course was uneventful. Failure to perform axial radiographs in the preoperative and postoperative period made it impossible to objectively determine the type of fracture and the quality of screw insertion into the femoral neck, and assessment limited to A-P images turned out to be deceptive. The wandering of the screw towards the acetabulum led to extensive destruction of the acetabular fossa. The decision to stop biological treatment, which, if properly performed, stimulates bone union, and perform the mechanical procedure of endoprosthesoplasty was fully prognostically justified. The early and late postoperative course was not complicated.

THEORETICAL COMPLEX ENERGIES OF STARK RESONANCES IN LITHIUM BY OPERATOR PERTURBATION THEORY APPROACH

The theoretical complex energies of the Stark resonances in the lithium atom (non-hydrogenic atomic system) in a DC electric are calculated within the operator form of the modified perturbation theory for the non-H atomic systems. The method includes the physically reasonable distorted-waves approximation in the frame of the formally exact quantum-mechanical procedure. The calculated Stark resonances energies and widths in the lithium atom are calculated and compared with results of calculations on the basis of the method of complex eigenvalue Schrödinger equation by Themelis-Nicolaides, the complex absorbing potential method by Sahoo-Ho and the B-spline-based coordinate rotation method approach by Hui-Yan Meng et al.

Evaluation of a new nomogram for Ferrara ring segment implantation in keratoconus

AIM: To evaluate the short-term clinical outcomes of Ferrara rings in keratoconus using an optimized nomogram developed after several years of research and retrospective analysis of clinical data. METHODS: This prospective longitudinal non-comparative clinical trial evaluated 88 eyes of 88 patients (age 18-62y) with keratoconus diagnosis from two Spanish centers. Ferrara ring segment (AJL Ophthalmic) implantation was performed in all cases, using the mechanical procedure in 25 eyes (28.4%) and a femtosecond laser-assisted procedure in 63 eyes (71.6%). The ring segments implanted in each case were selected using a new optimized nomogram that considered variables such as anterior corneal asphericity and astigmatism or the discrepancy among astigmatism and coma orientations. Visual, refractive, corneal topographic, aberrometric, and pachymetric changes after surgery were evaluated during a 3-month follow-up. RESULTS: The implants induced a significant refractive change as well as an improvement in uncorrected (UDVA) and corrected distance visual acuity (CDVA; P<0.001). Postoperative CDVA of 0.10 logMAR or better was achieved in 28.4% and 46.5% of eyes, respectively. Two eyes (2.3%) lost two or more lines of CDVA whereas a total of 53.5% of eyes gained lines of CDVA. A significant central anterior and posterior corneal flattening was induced (P≤0.003), with a significant reduction of anterior (P<0.001) and posterior corneal astigmatisms (P=0.048), and a change in anterior asphericity (P<0.001). Total primary coma (6 mm pupil) change was also statistically significant (preoperative 3.66±3.04 µm vs postoperative 2.33±2.26 µm, P<0.001). No significant differences were found in the effect of ring segments between cases implanted using the mechanical and femtosecond techniques (P≥0.101). CONCLUSION: The implantation of Ferrara rings based on the nomogram evaluated is safe and effective for promoting a visual rehabilitation in keratoconus, with a relevant control of primary coma aberration.

Error on the Estimation of Sand Size Parameters When Using Small Diameter Sieves and a Solution

Analyses were carried out to determine the main sand size parameters (median grain size D50 and sorting σ) for beach nourishment purposes using the sieving method aboard a dredger. Due to a lack of space and the need to carry and use the material with ease, the sieves are commonly small (10 cm diameter), and the shaking procedure is usually performed by hand. However, the influence of shaking, either mechanically or manually, has not yet been studied with 10 cm diameter sieves. Therefore, 20 samples were taken from inside the hopper of a trailing suction dredger and sieved both manually and mechanically for 10 min. The results showed that manual sieving yielded higher D50 values than the mechanical procedure. The average error arising from using the manual method was 14%, but it can reach 36.5%. The granulometric analysis carried out for different shaking times has shown that this error is &lt; 5% when at least 20 min of shaking is performed. The mechanical procedure gave always finer sand results. In addition, the overfill ratio calculated for both mechanical and manual results reached differences of up to 48%.

PyTheis—A Python Tool for Analyzing Pump Test Data

The Theis equation is an important mathematical model used for analyzing drawdown data obtained from pumping tests to estimate aquifer parameters. Since the Theis model is a nonlinear equation, a complex graphical procedure is employed for fitting this equation to pump test data. This graphical method was originally proposed by Theis in the late 1930s, and since then, all the groundwater textbooks have included this fitting method. Over the past 90 years, every groundwater hydrologist has been trained to use this tedious procedure for estimating the values of aquifer transmissivity (T) and storage coefficient (S). Unfortunately, this mechanical procedure does not provide any intuition for understanding the inherent limitations in this manual fitting procedure. Furthermore, it does not provide an estimate for the parameter error. In this study, we employ the public domain coding platform Python to develop a script, namely, PyTheis, which can be used to simultaneously evaluate T and S values, and the error associated with these two parameters. We solve nine test problems to demonstrate the robustness of the Python script. The test problems include several published case studies that use real field data. Our tests show that the proposed Python script can efficiently solve a variety of pump test problems. The code can also be easily adapted to solve other hydrological problems that require nonlinear curve fitting routines.

Generating fuzzy sets from the families of sets

The main purpose of this paper is to establish a mechanical procedure to determine the membership functions using the data collected from the economic and engineering problems. Determining the membership functions from the collected data may depend on the subjective viewpoint of decision makers. The mechanical procedure proposed in this paper can get rid of the subjective bias of decision makers. The concept of solid families is also proposed by regarding the sets in a family to be continuously varied. The desired fuzzy sets will be generated in the sense that its α-level sets will be identical to the sets of the original family. In order to achieve this purpose, any arbitrary families will be rearranged as the nested families by applying some suitable functions to the original families that are formulated from the collected data.

Measurement of wind erosion and dust emission triggered by different tillage tools

&lt;p&gt;Mechanized vineyard floor tillage aims at minimizing negative impact of weeds on water competition and spread of pests and diseases without herbicide application. It includes tillage between vines, in the vine row, and in headlands around vineyard blocks. While there is an increased awareness from vine growers and scientists concerning water erosion, wind erosion and dust emission are largely unnoticed processes that have not been investigated yet. The emission of soil particles seems to be strongly associated to the working of the soil surface by means of (tracked) tractor. This impact may be particularly important on surfaces considered erosion stable due to vegetation or stone cover preventing soil from direct detachment by wind.&lt;/p&gt;&lt;p&gt;The row-tillage only underneath the vines is an important management practice in modern and in organic viticulture because of the strongly reduced soil disturbance compared with clearing of the complete vineyard floor area. We investigated tillage as a trigger for wind erosion and dust production on particularly inclined vineyards in this study.&lt;/p&gt;&lt;p&gt;Three different tillage tools in three combinations were tested on two different steep-slope vineyards by means of modified Wilson and Cook Sampler (MWACS): rotary hoe, disc plow, and finger weeder.&lt;/p&gt;&lt;p&gt;We measured eroded material on both sites for different states of soil moisture and wind intensity. The results suggest a relationship between particular tillage tool combinations and airborne substrate particles that correspond to the general mechanical procedure.&lt;/p&gt;&lt;p&gt;These first results for measurement of tillage-induced wind erosion and dust emission indicate a considerable potential of vineyards to release dust that is related to specific management device needs to be investigated by means of qualitative analysis, flux measurements and monitoring.&lt;/p&gt;

Data Analytics and Its Applications in Brief

With an ever-increasing amount of data created, it has become a major challenge for infrastructures and frameworks to process a lot of information inside stipulated time and resources. So as to effectively extract from this information, organizations are required to discover new devices and strategies in particular for large information preparation. Therefore, data analytics has become a key factor for organizations to uncover hidden data and accomplish the upper hand in the market. As of now, tremendous distributions of larger data and information processing make it hard for experts and specialists to discover points they are keen on and track forward-thinking. This chapter puts forth an outline of data analytics, extension, and discoveries just as opportunities emancipated by analysis of data. The chapter also deals with various applications of data analytics which include applying an algorithmic or mechanical procedure to infer bits of knowledge, for instance, going through a few informational collections to search for significant connections between one another.

Integrated Empirical-mechanical Seismic Vulnerability Analysis Method for Masonry Buildings in Timișoara: Validation based on the 2009 Italian Earthquake

Background: Timisoara is one of the most important Romanina cities, located in the Banat area and characterised by shallow earthquakes with high ground motion vertical component. The seismicity of the area, in accordance with the P-100 Romanian Code, is affected by medium-high hazard level with an expected maximum PGA of 0.20 g. From a historical-artistic point of view, the city of Timisoara is full of monumental buildings of inestimable values and it was declared as the European Capital of Culture for 2021. Aims: The present work aims to investigate the seismic vulnerability of masonry buildings located in the districts of Fabric and Iosefin, which were grouped in typology classes based on the EMS-98 scale according to their geometrical and structural characteristics. Methods: The performed vulnerability analysis is based on a combined empirical-mechanical procedure to estimate the propensity at the damage of the buildings surveyed. Results: A specific formulation was proposed for typological vulnerability curves of building classes of the examined area, which were calibrated on the basis of the damages detected after occurred earthquakes. Conclusion: The proposed formulation was validated from the application to an urban sector of the municipality of San Pio delle Camere (Italy), which was damaged after the 2009 Abruzzo earthquake.

Surprisal of a Quantum State: Dynamics, Compact Representation and Coherence Effects

<p>Partially averaged or resolved distributions of quantum states are measured (or simulated) in diverse branches of Physics, in Chemical Physics and more recently in Biological Physics. Lately they are an output of quantum computations. Surprisal analysis, a blending of information theory and thermodynamics has been extensively used to characterize and compact such distributions. Currently, when coherence between quantum states is of central interest, the algebraic awkwardness of implementing a quantum mechanical procedure of maximal entropy is becoming an issue. We present a novel theoretical approach and its practical computational implementation with special reference to dynamical processes.</p>