bluuebunny/crossref_metadata_2025 huggingface dataset:
Decreased and increased relative acetabular volume predict the development of osteoarthritis of the hip
Authors: Weinberg D. S. , Williamson D. F. K. , Millis M. B. , Liu R. W.
Published: April 2017

Aims

Recently, there has been considerable interest in quantifying the associations between bony abnormalities around and in the hip joint and osteoarthritis (OA). Our aim was to investigate the relationships between acetabular undercoverage, acetabular overcoverage, and femoroacetabular impingement (FAI) with OA of the hip, which currently remain controversial.

Materials and Methods

A total of 545 cadaveric skeletons (1090 hips) from the Hamann-Todd osteological collection were obtained. Femoral head volume (FHV), acetabular volume (AV), the FHV/AV ratio, acetabular version, alpha angle and anterior femoral neck offset (AFNO) were measured. A validated grading system was used to quantify OA of the hip as minimal, moderate, or severe. Multiple linear and multinomial logistic regression were used to determine the factors that correlated independently with the FHV, AV, and the FHV/AV ratio.

Results

Female cadavers had smaller FHVs (standardised beta -0.382, p < 0.001), and AVs (standardised beta -0.351, p < 0.001), compared with male patients, although the FHV/AV ratio was unchanged. Every 1° increase in alpha angle increased the probability of having moderate OA of the hip compared with minimal OA by 7.1%. Every 1 mm decrease in AFNO increased the probability of having severe or moderate OA of the hip, compared with minimal OA, by 11% and 9%, respectively. The relative risk ratios of having severe OA of the hip compared with minimal OA were 7.2 and 3.3 times greater for acetabular undercoverage and overcoverage, respectively, relative to normal acetabular cover.

Conclusion

Acetabular undercoverage and overcoverage were independent predictors of increased OA of the hip. The alpha angle and AFNO had modest effects, supporting the hypothesis that bony abnormalities both in acetabular dysplasia and FAI are associated with severe OA. Cite this article: Bone Joint J 2017;99-B:432–9.
Is there still a role for osteoarticular allograft reconstruction in musculoskeletal tumour surgery?
Authors: Bus M. P. A. , van de Sande M. A. J. , Taminiau A. H. M. , Dijkstra P. D. S.
Published: April 2017

Aims

To assess complications and failure mechanisms of osteoarticular allograft reconstructions for primary bone tumours.

Patients and Methods

We retrospectively evaluated 38 patients (28 men, 74%) who were treated at our institution with osteoarticular allograft reconstruction between 1989 and 2010. Median age was 19 years (interquartile range 14 to 32). Median follow-up was 19.5 years (95% confidence interval (CI) 13.0 to 26.1) when 26 patients (68%) were alive. In addition, we systematically searched the literature for clinical studies on osteoarticular allografts, finding 31 studies suitable for analysis. Results of papers that reported on one site exclusively were pooled for comparison.

Results

A total of 20 patients (53%) experienced graft failure, including 15 due to mechanical complications (39%) and three (9%) due to infection. In the systematic review, 514 reconstructions were analysed (distal femur, n = 184, 36%; proximal tibia, n = 136, 26%; distal radius, n = 99, 19%; proximal humerus, n = 95, 18%). Overall rates of failure, fracture and infection were 27%, 20%, and 10% respectively. With the distal femur as the reference, fractures were more common in the humerus (odds ratio (OR) 4.1, 95% CI 2.2 to 7.7) and tibia (OR 2.2, 95% CI 1.3 to 4.4); infections occurred more often in the tibia (OR 2.2, 95% CI 1.3 to 4.4) and less often in the radius (OR 0.1, 95% CI 0.0 to 0.8).

Conclusion

Osteoarticular allograft reconstructions are associated with high rates of mechanical complications. Although comparative studies with alternative techniques are scarce, the risk of mechanical failure in our opinion does not justify routine employment of osteoarticular allografts for reconstruction of large joints after tumour resection. Cite this article: Bone Joint J 2017;99-B:522–30.
Proximal translation of > 1 mm within the first two years of revision total hip arthroplasty correctly predicts whether or not an acetabular component is loose in 80% of cases
Authors: Kim Y. S. , Abrahams J. M. , Callary S. A. , De Ieso C. , Costi K. , Howie D. W. , Solomon L. B.
Published: April 2017

Aims

The purpose of this study was to determine the sensitivity, specificity and predictive values of previously reported thresholds of proximal translation and sagittal rotation of cementless acetabular components used for revision total hip arthroplasty (THA) at various times during early follow-up.

Patients and Methods

Migration of cementless acetabular components was measured retrospectively in 84 patients (94 components) using Ein-Bild-Rontgen-Analyse (EBRA-Cup) in two groups of patients. In Group A, components were recorded as not being loose intra-operatively at re-revision THA (52 components/48 patients) and Group B components were recorded to be loose at re-revision (42 components/36 patients).

Results

The mean proximal translation and sagittal rotation were significantly higher in Group B than in Group A from three months onwards (p < 0.02). Proximal translation > 1.0 mm within 24 months had a positive predictive value (PPV) of 90% and a specificity of 94%, but a sensitivity of 64%. Proximal translation > 1.0 mm within the first 24 months correctly identified 76 of 94 (81%) of components to be either loose or not loose. However, ten components in Group B (24%) did not migrate proximally above 1.0 mm within the first 60 months.

Conclusion

The high PPV of EBRA-Cup measurements of proximal translation (90%) shows that this can be used in early follow-up to identify patients at risk of aseptic loosening. The absence of proximal translation within the first 60 months indicates a component is not likely to be loose at re-revision THA although it does not exclude late aseptic loosening as a cause of failure. Cite this article: Bone Joint J 2017;99-B:465–74.
The stability of the hip after the use of a proximal femoral endoprosthesis for oncological indications
Authors: Henderson E. R. , Keeney B. J. , Pala E. , Funovics P. T. , Eward W. C. , Groundland J. S. , Ehrlichman L. K. , Puchner S. S. E. , Brigman B. E. , Ready J. E. , Temple H. T. , Ruggieri P. , Windhager R. , Letson G. D. , Hornicek F. J.
Published: April 2017

Aims

Instability of the hip is the most common mode of failure after reconstruction with a proximal femoral arthroplasty (PFA) using an endoprosthesis after excision of a tumour. Small studies report improved stability with capsular repair of the hip and other techniques, but these have not been investigated in a large series of patients. The aim of this study was to evaluate variables associated with the patient and the operation that affect post-operative stability. We hypothesised an association between capsular repair and stability.

Patients and Methods

In a retrospective cohort study, we identified 527 adult patients who were treated with a PFA for tumours. Our data included demographics, the pathological diagnosis, the amount of resection of the abductor muscles, the techniques of reconstruction and the characteristics of the implant. We used regression analysis to compare patients with and without post-operative instability.

Results

A total of 20 patients out of 527 (4%) had instability which presented at a mean of 35 days (3 to 131) post-operatively. Capsular repair was not associated with a reduced rate of instability. Bivariate analysis showed that a posterolateral surgical approach (odds ratio (OR) 0.11, 95% confidence interval (CI) 0.02 to 0.86) and the type of implant (p = 0.046) had a significant association with reduced instability; age > 60 years predicted instability (OR 3.17, 95% CI 1.00 to 9.98). Multivariate analysis showed age > 60 years (OR 5.09, 95% CI 1.23 to 21.07), female gender (OR 1.73, 95% CI 1.04 to 2.89), a malignant primary bone tumour (OR 2.04, 95% CI 1.06 to 3.95), and benign condition (OR 5.56, 95% CI 1.35 to 22.90), but not metastatic disease or soft-tissue tumours, predicted instability, while a posterolateral approach (OR 0.09, 95% CI 0.01 to 0.53) was protective against instability. No instability occurred when a synthetic graft was used in 70 patients.

Conclusion

Stability of the hip after PFA is influenced by variables associated with the patient, the pathology, the surgical technique and the implant. We did not find an association between capsular repair and improved stability. Extension of the tumour often dictates surgical technique; however, our results indicate that PFA using a posterolateral approach with a hemiarthroplasty and synthetic augment for soft-tissue repair confers the lowest risk of instability. Patients who are elderly, female, or with a primary benign or malignant bone tumour should be counselled about an increased risk of instability. Cite this article: Bone Joint J 2017;99-B:531–7.
In situ pinning in slipped capital femoral epiphysis: long-term follow-up studies
Authors: Accadbled F. , Murgier J. , Delannes B. , Cahuzac J. P. , de Gauzy J. Sales
Published: April 2017

Background

Management of moderately displaced slipped capital femoral epiphysis (SCFE) is debated, mostly because of the risks related to open reduction on one hand, and subsequent evolution toward femoroacetabular impingement (FAI) on the other.

Method

All SCFE cases treated with in situ fixation (ISF) and a minimum of ten years of follow-up beyond skeletal maturity were analysed in a retrospective multicentre study. Coxometry parameters were measured. Long-term results of ISF were meanwhile analysed at our Institution.

Results

A total of 222 patients were included. Patient reported outcome measurements were related to the severity of the initial slip. It suggested a 35.5° threshold for slip angle beyond which FAI was more frequent. Only slight remodelling at the head-neck junction is to be expected.

Conclusion

Based on these findings, it seems reasonable to perform ISF only in SCFE with a slip angle below 35°.
Slipped capital femoral epiphysis: A spectrum of surgical care and changes over time
Authors: Loder R. T.
Published: April 2017

Purpose

To survey the spectrum of surgical care in children with slipped capital femoral epiphysis (SCFE). This information is valuable in counselling the patient about the future treatment course.

Methods

Data for this study were obtained from the Pediatric Hospital Information System (PHIS) between 2004 and 2015. For all patients with an ICD9 diagnosis of 732.2, gender, ethnicity, hospital, medical record number, date of birth/admission/discharge, type of admission, length of stay, disposition and treatment(s) rendered were collected.

Results

A total of 13 168 procedures were performed in 11 058 unique SCFE patients, or 1.2 procedures per patient. Primary procedures were those performed for the initial treatment of the SCFE and secondary procedures as reconstructive and salvage. The majority (11 693, 88.8%) were primary. There was significant variation in the ratio of primary and secondary procedures by institution. There was a decline in in situ fixation as the initial SCFE treatment with an increase in open reduction and internal fixation over the 12-year span. Similarly, there was a significant increase in the number of secondary procedures over time as well as complications and implant removal. There was no change over time in the diagnosis of avascular necrosis.

Conclusions

The average number of surgical procedures in patients was in the range of 1 to 6 and varied widely by hospital. Each physician should know his/her own hospital's data for the percentage of subsequent procedures so as to counsel the patient and family properly. The increasing number of complications over time may reflect the increasing number of more complex procedures.
Special symposium issue: Slipped capital femoral epiphysis (SCFE)
Authors: Krauspe R. , Weinstein S.
Published: April 2017

Up-date on the pathogenesis, epidemiology, pathology, histopathology, clinical findings, diagnosis & classification, imaging modalities and all treatment options in slipped capital femoral epiphysis. This symposium issue of JCO is based on lectures presented at the Pre-Course at the 35th Annual Congress of the European Paediatric Orthopaedic Society (EPOS) in 2016.
Patient-specific 3D models aid planning for triplane proximal femoral osteotomy in slipped capital femoral epiphysis
Authors: Cherkasskiy L. , Caffrey J. P. , Szewczyk A. F. , Cory E. , Bomar J. D. , Farnsworth C. L. , Jeffords M. , Wenger D. R. , Sah R. L. , Upasani V. V.
Published: April 2017

Purpose

Slipped capital femoral epiphysis (SCFE) can result in a complex three-dimensional (3D) deformity of the proximal femur. A three-plane proximal femoral osteotomy (TPFO) has been described to improve hip mechanics. The purpose of this study was to evaluate the benefits of using 3D print technology to aid in surgical planning.

Patients and Methods

Fifteen children treated with TPFO for symptomatic proximal femoral deformity due to SCFE were included in this study. Ten patients were treated by a single surgeon with (model group, n = 5) or without (no-model group, n = 5) a 3D model for pre-operative planning, and compared with patients treated by two senior partners without the use of a model (senior group, n = 5) to evaluate for a learning curve. Peri-operative data including patient body mass index (BMI), surgical time and fluoroscopy time were recorded.

Results

Children in all three groups had similar BMIs at the time of the TPFO. Post-operative radiographic parameters were equally improved in all three groups. On average, surgical time decreased by 45 minutes and 38 minutes, and fluoroscopy time decreased by 50% and 25%, in the model group compared with the no-model and senior groups, respectively.

Conclusions

Patient-specific 3D models aid in surgical planning for complex 3D orthopaedic deformities by enabling practice of osteotomies. Results suggest that 3D models may decrease surgical time and fluoroscopy time while allowing for similar deformity correction. These models may be especially useful to overcome steep learning curves for complex procedures or in trainee education through mock surgical procedures.
Algorithms of common solutions for a fixed point of hemicontractive-type mapping and a generalized equilibrium problem
Authors: Zegeye Habtu , Hadush Meche Tesfalem , Goa Sangago Mengistu
Published: April 2017

In this paper, we introduce and study an iterative algorithm for finding a common element of the set of fixed points of a Lipschitz hemicontractive-type multi-valued mapping and the set of solutions of a generalized equilibrium problem in the framework of Hilbert spaces. Our results improve and extend most of the results that have been proved previously by many authors in this research area.
Software, Server, Suchmaschine – Technische Kriterien der Gründung und des Betriebs von (Diamond) Open Access-Zeitschriften
Authors: Ledl Andreas
Published: April 2017

Der vorliegende Beitrag beschreibt, wie mit Hilfe non-proprietärer Software eine technische Publikationsinfrastruktur für unabhängige Open-Access-Zeitschriften aufgesetzt werden kann. Er stellt eine Auswahl an Systemen zur Verwaltung und Veröffentlichung wissenschaftlicher Journals sowie Tools zur Erzeugung verschiedener Artikel-Formate vor. Darüber hinaus werden Möglichkeiten des Hostings und der Indexierung einer Zeitschrift thematisiert. Schließlich präsentiert er mit PubPub eine benutzerfreundliche und für Anhänger von mehr Offenheit im wissenschaftlichen Publikationswesen zukunftsträchtige Alternative zu OJS.
Evaluation of Subsoil Compaction of Plastic Soils
Authors: Śnieg Kinga , Błażejczak Dariusz
Published: April 2017

The objective of the research was to evaluate soil compaction with selected indexes and to determine the relation between them including results obtained with Proctor’s method. Measurements of penetration resistance and shear vane, dry density of soil particles (ρd) and their moisture were made in layers in the following depths: 25-30, 35-40, 45-50 and 55-60 cm. Moreover, the maximum volumetric density of soil particles, particles size distribution, content of calcium carbonate and humus, density of solid particles, reaction, plastic and liquid limit were determined with Proctor's method (ρds). Also, packing density and natural density were measured. It was found out that the investigated soils may be generally included to excessively compacted and susceptible to compaction to an average and small degree. It was shown that soil may be recognized as excessively compacted when the quotient ρd/ρds exceeds the value of 0.87.
Springback Prediction of Stretching Process using Finite Element Analysis for DP600 Steel Sheet
Authors: Slota Jan , Gajdos Ivan , Spišák Emil , Šiser Marek
Published: April 2017

Springback phenomenon is well predicted for some mild steel materials, but not for steels with higher strength. One of the most used tools to stamping optimization is usage of finite element analysis. In order to accurate describe the real behaviour of the materials for stamping of vehicle panels, the application of proper hardening rule seems to be crucial. Due to higher accuracy of predicted results, high strength steel sheets are usually modelled by means of kinematic or mixed isotropic-kinematic hardening models. In this paper the springback prediction of advanced high strength steel DP600 by numerical simulation was investigated. Through cyclic tension-compression tests, the material characterization has been performed for DP600 steel sheet. Different hardening models (isotropic, kinematic and mixed isotropic-kinematic) used in the simulations were compared with expreriment. The Yoshida–Uemori model succesfully describe the kinematic behaviour of the material and provided more accurate results than others.
Determination of Cutting Forces in Grinding with Crossed Axes of Tool and Workpiece
Authors: Kalchenko Volodimyr , Yeroshenko Andrij , Boyko Sergiy , Sira Nataliia
Published: April 2017

In the work the analysis of existent methods of determination of local and general forces of cutting at polishing of surfaces with a type as the arc of circumference is given. The dependence for determination of speed polishing and method for determination of thickness of the cut away layer on condition of equality of the tricked into and taken off volumes of material are offered. The method of determination of cutting forces, which takes into account cutting and deforming grain, is suggested. The method of determining the thickness of a cutting layer of one of the cutting edge, from the condition that the volume of material that is brought and is cut in each local point of contact spots has been proposed. The proposed method takes into account the compliance of the processing system and the discontinuity of the abrasive surface of the tool. By experimental way upper limits of thickness cutting layer when using different abrasive materials for a wide range of cutting speeds have been obtained.
Carbon Nanomaterials Application as a Counter Electrode for Dye-Sensitized Solar Cells
Authors: Dobrzański L. A. , Prokopiuk vel Prokopowicz M. , Drygała A. , Wierzbicka A. , Lukaszkowicz K. , Szindler M.
Published: April 2017

The paper presents the results of the structure investigation of a counter electrode in dye-sensitized solar cells using the carbon nanomaterials. Solar cells were fabricated on the glass with transparent conductive oxide TCO (10Ω/sq). Nanocrystalline titania based photoanode was prepared by spreading TiO2paste onto TCO glass and subsequently annealed at 450°C for at least 30 min to convert anatase phase and make an interparticle network. After then the nanostructured titania films was immersed into an ethanolic solution of the ruthenium-based dye. As a counter electrodes of dye-sensitized solar cells composite films of carbon nanomaterials and polystyrene sulfonate doped poly (3,4-ethylenedioxythiophene) PEDOT-PSS (Sigma-Aldrich) were deposited onto TCO substrates. Because carbon nanoelements and titanium oxide consist of nano-metric structural units to determine the properties of the cells and their parameters several surface sensitive techniques and methods, i.e. Raman spectroscopy, Scanning Electron Microscopy (SEM), High-Resolution Transmission Electron Microscopy (HRTEM), and electric properties of conductive layers were used.
Influence exerted by the shape of the surfaces of working roll barrels upon the course of the MEFASS (Metal Forming Aided by Shear Stresses) rolling process
Authors: Świątoniowski A. , Woźniak D. , Szostak J.
Published: April 2017

The essential aspect of the MEFASS rolling process is introducing the cyclic axial counter movement of the rolls transverse to the direction of rolling in the course of a band pass through a rolling gap. The effect of a change in the way of deformation obtained in this manner makes it possible to set in one roll pass a deformation several times larger than it is possible in a conventional process. In this paper, upon the basis of the computer model of the MES process, supported by experimental research, the analysis of the influence exerted by the shape of the surface of roll barrels upon the distribution of the intensity of stresses σi and deformations εi in the section of the band being rolled, and also upon the kinematic and force parameters of the process.
The role of β(Al12Mg17) phase on corrosion behavior of the AZ91 alloy in NaCl aqueous solution
Authors: Hatakeyama M. , Shimono K. , Iwashima D. , Saikawa S. , Sunada S.
Published: April 2017

The effect of the β phase (Al12Mg17) on the corrosion resistance in a NaCl solution was investigated by electro chemical methods.Volume fraction of β phase in each specimen was controlled systematically by isothermal annealing at 473 K as 0%, 4%, 22% and 100 %, respectively. Although α phase shows lower corrosion current density than that of β phase, the α/β mixed phase specimen showed higher corrosion current density than that of α phase.It strongly suggests that β phase act as cathodic electrode in the alloys.
Pearlitic Lamellae Spheroidisation During Austenitization and Subsequent Temperature Hold
Authors: Hauserova D. , Dlouhy J. , Kover M.
Published: April 2017

Typical processing routes for bearing steels include a soft annealing stage. The purpose of this procedure is to obtain a microstructure containing globular carbides in ferritic matrix. A newly developed process called ASR (Accelerated Spheroidisation and Refinement) cuts the carbide spheroidisation times several fold, producing considerably finer globular carbides than conventional soft annealing. Finer microstructure also leads to more homogeneous and finer structure after final hardening process. The present paper explores process of the accelerated spheroidisation (ASR) in steel 100CrMnSi6-4 with initial pearlitic structure. Cementite lamellae morphology was observed in different stages of austenitization. The heat treatment was performed using induction heating in quenching dilatometer. There was analysed influence of austenitization temperature and austenitization time on spheroidisation. Hardness and carbide morphology was observed. Deep etching was used to reveal evolution of cementitic lamellae fragmentation. It is favourable process especially in induction treatment of small parts.
The effect of alloying method on the structure and properties of sintered stainless steel
Authors: Dudek A. , Lisiecka B. , Ulewicz R.
Published: April 2017

Sintered duplex stainless steels (SDSSs) appear to be very interesting and promising materials that can be used in many industrial sectors. Ferrite improves material strength while austenite increases hardness and corrosion resistance. This study proposes a method to improve functional properties (e.g. hardness and wear resistance) by means of alloying the surface of the sintered duplex steel with Cr3C2+ 10% NiAl powder. The results of optical microscope metallography, SEM/EDX, XRD analysis and microhardness and wear resistance measurements are also presented. The surface alloying with Cr3C2is a manufacturing method of surface layer hardening in sintered stainless steels and modification of surface layer properties such as hardness and coefficient of friction.
The thermal and structural analysis of new bicomponent binders for moulding sands consisting of furfuryl resin and polycaprolactone (PCL)
Authors: Major-Gabryś K. , Bobrowski A. , Grabarczyk A. , Dobosz St. M.
Published: April 2017

The aim of the article is thermal and structural analysis of new two-component binders for foundry moulding sands. The previous research showed the possibility of using biodegradable materials as binders or parts of binders’ compositions for foundry moulding and core sands. This paper is concentrated on estimating the influence of PCL on phenol-furfuryl resin thermal destruction (measured by derivatographic research) and its structure (measured by FTiR technology). The research proved that addition of new biodegradable additive PCL in the amount of 5-15% to the phenol-furfuryl resin doesn’t change the resin thermal destruction course but it results in appearance of a new band in two-component binder structure. What’s more there has been noticed a growth of intensity for band at wavenumber 1730 cm-1 (C = O) with the increasing addition of PCL.
Study of the precipitation hardening process in recycled Al-Si-Cu cast alloys
Authors: Kuchariková L. , Tillová E. , Matvija M. , Belan J. , Chalupová M.
Published: April 2017

The formation of extremely small uniformly dispersed particles of a second phase within the original phase matrix during heat treatment changed material properties. Therefore the characterization of precipitation had been investigated using high resolution transmission electron microscopy (TEM) and electron diffraction of thin foils for an AlSi9Cu3 cast alloy. For investigation the hardening effect onto mechanical properties of aluminium cast was used heat treatment, which consisted from solution treatment at 515°C / 4 hours (h), followed by quenching into water with temperature 50°C and artificial aging using different temperatures 170°C and 190°C with different holding time 2, 4, 8, 16, and 32 hours. The observations of microstructure and substructure reveals that precipitation hardening has caused great changes in size, morphology and distributions of structural components, the formation of precipitates of Cu phases, and the change of mechanical properties as well.
Electrophoretic deposition of nc-TiO2/chitosan composite coatings on X2CrNiMo17-12-2 stainless steel
Authors: Ledwig P. , Kot M. , Moskalewicz T. , Dubiel B.
Published: April 2017

This paper presents the results of the optimization of electrophoretic deposition parameters for manufacturing of nc-TiO2/chitosan composite coatings on X2CrNiMo17-12-2 steel as well as characterization of their microstructure, electrochemical properties and adhesion to the substrate. The parameters of the deposition, such as composition, pH and zeta potential of suspensions as well as voltage and process time were investigated. The microstructure of the coatings was characterized using scanning and transmission electron microscopy. Obtained coatings were crack-free and uniform. The adhesion strength to the substrate was measured by scratch-test method. The deposited coatings improve corrosion resistance of steel, what was confirmed by the results of the potentiodynamic polarization test in Ringer’s solution.
Geometry of product complex Cartan manifolds
Authors: Aldea Nicoleta , Munteanu Gheorghe
Published: April 2017

In this paper we consider the product of two complex Cartan manifolds, the outcome being a class of product complex Cartan spaces. Then, we study the relationships between the geometric objects of a product complex Cartan space and its components, (e.g. Chern-Cartan complex nonlinear connection, Cartan tensors). By means of these, we establish the necessary and sufficient conditions under which a product complex Cartan space is Landsberg-Cartan or Berwald-Cartan or it has some other properties.
The Relationships Between p−valent Functions and Univalent Functions
Authors: Çağlar Murat
Published: April 2017

In this paper, we obtain some sufficient conditions for general p−valent integral operators to be the p−th power of a univalent functions in the open unit disk.
An adaptive stepsize algorithm for the numerical solving of initial-value problems
Authors: Militaru Romulus
Published: April 2017

The present paper focuses on the efficient numerical solving of initial-value problems (IVPs) using digital computers and one-step numerical methods. We start from considering that the integration stepsize is the crucial factor in determining the number of calculations required and the amount of work involved to obtain the approximate values of the exact solution of a certain problem for a given set of points, within a prescribed computational accuracy, is proportional to the number of accomplished iterations. We perform an analysis of the local truncation error and we derive an adaptive stepsize algorithm which coupled with a certain one-step numerical method makes the use of this structure more computationally effective and insures that the estimated values of the exact solution are in agreement with an imposed accuracy. We conclude with numerical computations proving the efficiency of the proposed step selection algorithm.
On a subclass of analytic functions involving harmonic means
Authors: Tudor Andreea-Elena , Rǎducanu Dorina
Published: April 2017

In the present paper, we consider a generalised subclass of analytic functions involving arithmetic, geometric and harmonic means. For this function class we obtain an inclusion result, Fekete-Szegö inequality and coefficient bounds for bi-univalent functions.
A decomposition model and voxel selection framework for fMRI analysis to predict neural response of visual stimuli
Authors: Raut Savita V. , Yadav Dinkar M.
Published: April 2017

This paper presents an fMRI signal analysis methodology using geometric mean curve decomposition (GMCD) and mutual information-based voxel selection framework. Previously, the fMRI signal analysis has been conducted using empirical mean curve decomposition (EMCD) model and voxel selection on raw fMRI signal. The erstwhile methodology loses frequency component, while the latter methodology suffers from signal redundancy. Both challenges are addressed by our methodology in which the frequency component is considered by decomposing the raw fMRI signal using geometric mean rather than arithmetic mean and the voxels are selected from EMCD signal using GMCD components, rather than raw fMRI signal. The proposed methodologies are adopted for predicting the neural response. Experimentations are conducted in the openly available fMRI data of six subjects, and comparisons are made with existing decomposition models and voxel selection frameworks. Subsequently, the effect of degree of selected voxels and the selection constraints are analyzed. The comparative results and the analysis demonstrate the superiority and the reliability of the proposed methodology.
Improvement of Range Estimation with Microphone Array
Authors: Kudriashov Volodymyr
Published: April 2017

This paper presentsanew approach for the three-dimensional (3-D) localization of sound sources. An acoustic camera uses an angular beamforming to measure the Direction of Arrival (Do A) of an incoming signal, to localize the emission source. The acoustic sensor used in this article is the Brüel & Kjaer acoustic camera transformed to operate inabistatic mode. The transformation consists inaplacing of one of the microphones of the acoustic camera outside of its microphone array. This allows simultaneous estimation of the Do Aand the Time Difference of Arrival (TDo A) of the incoming signal(s). Such sensors were not found. The paper proposes emitter localization in range - cross range - elevation coordinates by combining estimates of TDo Aand Do Aand presents the signal processing method for that purpose. The range resolution of 0.2mwas achieved in an experiment. Experimental results were obtained using different emission sources. Adescription of resolution cell limitations is presented. The obtained results show acoustic noise source localization without the pre-metering of the range of the imaging plane, i.e., withoutaneed to use the additional range meter which is notapart of the acoustic camera. The latter is important in tasks of non-destructive testing.
Research on Quick Response Code Defect Detection Algorithm
Authors: Yanhua Guo , Sihua Zhou , Xiaodong Zhou , Bojun Chen , Shaohui Wang
Published: April 2017

Defect Detection is one of the most important parts of Automatic Identification and Data transmission. Quick Response code (QRcode) is one of the most popular types of two-dimensional barcodes. It isachallenge to detect defect of various QRcode images efficiently and accurately. In this paper, we propose the procedure byaserial of carefully designed preprocessing methods. The defect detection procedure consists of QRcode identification, QRcode reconstruction, perspective transformation, image binarization, morphological operation, image matching, and Blob analysis. By these steps, we can detect defect of different types of QRcode images. The experiment results show that our method has stronger robustness and higher efficiency. Moreover, experiment results on QRcode images show that the prediction accuracy of proposed method reaches 99.07%with an average execution time of 6.592 ms. This method can detect defect of these images in real time.
Albania’s Transformation since 1997: Successes and Failures
Authors: Jusufi Islam
Published: April 2017

In 1997 Albania experienced a collapse of order and widespread violence, which resulted in a situation where the government was overthrown and some 2,000 people were killed. The 1997 disorder came as a result of the collapse of fraudulent financial pyramid schemes that had all the features of a war-like economic structure. During the 1997 events, large-scale confiscation and stealing of state assets occurred. Albania’s transitional period from communism to democracy, which began in 1990, led to the establishment of new structures for profiting from the country’s resources. Some of these political and economic structures, in the aftermath of the 1997 events, disappeared and others, including their structural effects, persist and have had an impact on the country’s political stability and economic progress. Today, both the successes and failures of the country are assessed based on the progress that the country has made since the 1997 events. The paper analyses the 1997 events and the transformation of Albania’s political and economic structures between 1997 and 2016, considering both achievements and failures. It looks at how the country has dealt with the post-1997 peace-building and development agenda from the perspective of it being a success. It looks at the factors that led to state failure in 1997 and at the factors that continue and have generated a path dependency to the current political context of the country. Although a lot has been written concerning the 1997 events, very little analysis has been conducted concerning what it means from the perspective of research on state failure. In this context, the proposed paper seeks to offer Albania as a case study example of a transformation process, from the uprising to the current situation, which is characterized as a mixture of successes and failures. The belief is that the proposed paper will point to some lessons learned for the strategies directed at the transformation processes.
Homokhátság - a special rural area affected by aridification in the Carpathian basin, Hungary
Authors: Kovács András Donát , Hoyk Edit , Farkas Jenő Zsolt
Published: April 2017

In Hungary, the aridification primarily affects the Great Hungarian Plain, most specifically the “Homokhátság” area which is part of the Danube-Tisza Interfluve. On the basis of our experience gained in the past 15 years, we would like to give an insight into the complex problems of this rural region. Our starting point is the aridification process and water scarcity which are characteristic features of this area for the last century. We investigate the related problems in land use management such as unfavourable land use and vegetation changes and the challenges in the local economy and social sustainability. In this respect we introduce the emerging issues in agriculture, forestry and nature conservation which may be relevant in European context too. We have discovered specific factors related to the devaluation of the rural environment and found that significant part of the unfavourable phenomena can be explained by the combined effect of climatic changes, improper land use and inappropriate environmental management. Based on our findings we outline a possible regional pathway for a sustainable rural development.
Land use changes in the last half century and their impact on water retention in the Šumava mountains and foothills (Czech Republic)
Authors: Bystřický Václav , Moravcová Jana , Polenský Jakub , Pečenka Jiří
Published: April 2017

Changes in land use and runoff characteristics in Otava river basin and its two subcatchment (Volšovka and Vydra) were examined. The goal was to find out how water retention have responded to changes in landscape management in Šumava mountains and foothills since the year 1970. There were two basic levels of changing land use - (a) conversion of arable land with varying intensity at different management of intensive and extensive grassland, (b) deforestation of large areas of indigenous mostly spruce monocultures and their transfer to the shrub and herbaceous vegetation covering the surface with a discontinuous vegetation. Water retention in Šumava mountains is locally reduced due to vulnerability of monoculture spruce forests by natural disasters (windstorms), diseases and pests. A positive effect of current agricultural management in the Šumava foothills on the reduction of direct runoff during intense rainfall was confirmed.
Tutor Emotional Competences Valued by Learners in a Blended Learning Contex
Authors: Youde Andrew
Published: April 2017

This paper outlines research into the emotional competences that mature, higher education students, undertaking part-time blended learning degrees within a School of Education, value in their tutors. A mixed methods approach was adopted to conduct a detailed exploration of eight tutors’ practice whilst teaching a module, with data gathered from three principal sources. Learners’ perceptions of their experiences were assessed using a questionnaire; interviews with tutors explored their approaches to delivery and considered factors that impacted on quality; and, an analysis of the content and communications in the virtual learning environment provided insight into tutors’ online practice. Goleman’s (2001) Framework of Emotional Competences provided a lens through which to analyse blended tutors’ practices in relation to learner perceptions. The paper proposes a framework of emotional competences that appeared to contribute to tutor effectiveness in this context. This research questions the value of some of Goleman’s relationship management competences, with the proposed framework developed to add further self-management competences. This was due, in part, to the measures evident by some tutors to effectively support these particular learners at a distance. The proposed framework could support recruitment and selection within higher education, and provide a language for discussing further research into blended and online tutors’ emotional competences.
An Evaluation of the African Leadership in ICT Programme from a Quality Assurance Perspective
Authors: Santally Mohammad
Published: April 2017

The aim of this paper is to present a comprehensive review of the African Leadership in ICT (ALICT-LATIC) course delivery model, offered by the Global e-Schools and Communities Initiatives (GESCI) from a quality assurance perspective taking into account the delivery model, cultural context, and the distributed nature of the programme and its participants, from a geographical perspective. In this paper, we look at the key concepts governing the ALICTLATIC course, such as the provision of transnational education and blended learning provisions. Through a series of steps including desk studies, expert observation and the application of the eLearning Maturity Model, we conduct an evaluation of the eLearning provision from a quality assurance perspective. We can reasonably argue at this stage that the current blended learning model is conducive for the development of skills and competencies as expected in terms of intended outcomes and learner experience. The quality of the course is comparable to academic standards adopted by institutions of higher education through their internal and external quality mechanisms.
In vitro rooting of Crocosmia × crocosmiiflora ‘Lucifer’
Authors: Krupa-Małkiewicz Marcelina , Żurawik Piotr
Published: April 2017

The aim of this study was to determine the effect of various auxins and their concentrations on Crocosmia × crocosmiiflora ‘Lucifer’ rooting in in vitro cultures and in vivo conditions. The initial research materials were shoots obtained from a stabilized in vitro culture. MS media were supplemented with the following auxins: IAA, IBA and NAA at concentrations of 0.5, 1.0, 2.0 and 5.0 mg dm-3. The results of the study showed that hormone applications had a positive effect on the root development of Crocosmia microshoots. 100% rooted shoots were observed in each of the applied combinations of the experiment. The highest number of roots and the longest roots were formed in the presence of IBA at a concentration of 1.0 mg dm-3. IAA, IBA and NAA affected plant height and root morphology of Crocosmia differently. The addition of higher concentrations of auxins to the medium (2.0 and 5.0 mg dm-3) resulted in the formation of short roots. The applied IBA concentrations determined the percentage of the plants that were adapted to in vivo conditions, as well as their vegetative features and the yield of descendant tubers. At the end of the vegetation period, higher IBA concentrations, i.e., 1.0, 2.0 and 5.0 mg dm-3, caused a decrease of up to 50-75% in the obtained plants and also inhibited plant height, as well as the weight and diameter of the tubers formed, compared to the control.
A Data Pre-Processing Model for the Topsis Method
Authors: Kobryń Andrzej , Prystrom Joanna
Published: April 2017

TOPSIS is one of the most popular methods of multi-criteria decision making (MCDM). Its fundamental role is the establishment of chosen alternatives ranking based on their distance from the ideal and negative-ideal solution. There are three primary versions of the TOPSIS method distinguished: classical, interval and fuzzy, where calculation algorithms are adjusted to the character of input rating decision-making alternatives (real numbers, interval data or fuzzy numbers). Various, specialist publications present descriptions on the use of particular versions of the TOPSIS method in the decision-making process, particularly popular is the fuzzy version. However, it should be noticed, that depending on the character of accepted criteria – rating of alternatives can have a heterogeneous character. The present paper suggests the means of proceeding in the situation when the set of criteria covers characteristic criteria for each of the mentioned versions of TOPSIS, as a result of which the rating of the alternatives is vague. The calculation procedure has been illustrated by an adequate numerical example.
Development of Bioethics and Clinical Ethics in Bulgaria
Authors: Aleksandrova-Yankulovska Silviya S.
Published: April 2017

Background: Bioethics and clinical ethics emerged from the classical medical ethics in the 1970s of the 20th century. Both fields are new for the Bulgarian academic tradition.

Aim: The aims of this paper were to demarcate the subject fields of medical ethics, bioethics, and clinical ethics, to present the developments in the field of medical ethics in Bulgaria, to delineate the obstacles to effective ethics education of medical professionals, and to present the results of the application of an adapted bottom-up methodology for clinical ethics consultation in several clinical units in Bulgaria.

Materials and methods: Extended literature review and application of an adapted METAP methodology for clinical ethics consultation in six clinical units in the Northern Bulgaria between May 2013 and December 2014.

Results: Teaching of medical ethics in Bulgaria was introduced in the 1990s and still stands mainly as theoretical expertise without sufficient dilemma training in clinical settings. Earlier studies revealed need of clinical ethics consultation services in our country. METAP methodology was applied in 69 ethics meetings. In 31.9% of them non-medical considerations affected the choice of treatment and 34.8% resulted in reaching consensus between the team and the patient. Participants’ opinion about the meetings was highly positive with 87.7% overall satisfaction.

Conclusion: Development of bioethics in Bulgaria follows recent worldwide trends. Several ideas could be applied towards increasing the effectiveness of ethics education. Results of the ethics meetings lead to the conclusion that it is a successful and well accepted approach for clinical ethics consultation with a potential for wider introduction in our medical practice.
Acquisition and Expansion of Adult Rat Bone Marrow Multipotent Mesenchymal Stromal Cells
Authors: Šulla I. , Balik V. , Šarišský M.
Published: April 2017

This study was initiated in order to test a mini-invasive method of mesenchymal stem/progenitor cells (MS/PCs) isolation from a rat bone marrow (BM), and subsequently their expansion, differentiation, and evaluation of their immunophenotypic characteristics; and later their preservation as donor cells in an optimal condition for potential autotransplantation. The study group comprised of 6 adult male Sprague-Dawley (S-D) rats, weighing 480—690 g. The rats were anaesthetised by isoflurane with room air in a Plexiglas box and maintained by inhalation of a mixture of isoflurane and O2. Their femurs were surgically exposed and their diaphyses double-trephined. Then BM cells were flushed out by saline with heparin and aspirated into a syringe with a solution of DMEM (Dulbecco’s modified eagle’s medium) and heparin. The mononuclear cells from the BM were isolated by centrifugation and expanded in a standard culture medium supplemented with ES-FBS (es-cell-qualified foetal bovine serum), L-glutamine and rh LIF (recombinant human leukemia inhibitory factor). Following 14 days of passaging cultures, the cells were split into 2 equal parts. The first culture continued with the original medium. The second culture received additional supplementation with a human FGFβ (fibroblast growth factor beta) and EGF (epidermal growth factor). The populations of these cells were analysed by light-microscopy, then the mean fluorescence intensities (MFIs) of CD90 and Nestin were evaluated by a tricolour flow cytometry using monoclonal antibodies. The type of general anaesthesia used proved to be appropriate for the surgical phase of the experiments. All rats survived the harvesting of the BM without complications. The total number of mononuclear cells was 1.5—4.0 × 106per sample and the proportion of CD90/Nestin expressing cells was < 1 %. Following 14 days of expansion, the cells became larger, adherent, with fibrillary morphology; the proportion of cells expressing CD90/Nestin increased to almost 25 %, i. e. they earned basic phenotypic characteristics of MSCs. Throughout the further cultivation a gradual decrease of the CD90/Nestin expression occurred. This suggested that the suitability of rat bone marrow derived MS/PCs for replacement therapy would probably be the highest between days 12—15 of cultivation and then would diminish.