The European construction industry and its competitiveness: a construct of the European Commission

The 'European construction industry' is a fiction that tends to obscure its heterogeneous character and to mar studies and policies of the European Commission aimed at improving the internal and external 'competitiveness' of the sector. In order to assess the process of integration in Europe under the impact of its own dynamics as well as Union policies, this paper looks at the dynamics of the sector from three different aspects: as investment, production and labour process. It shows, in particular, the persistent regional and social disparities dividing the industry into separate entities. Political attention tends to focus on a small number of construction companies competing for a few projects which represent the European dimension. Yet, these companies still rely on their respective national bases and local labour from the place where construction is carried out. Persistent divisions between the states are also reflected in the low level of transnational organization of the construction industry. The policy of the European Commission generally ignores these divisions and attempts to establish principles intended to make a whole sector more 'competitive', while its component parts, operating at hugely different levels of productivity, do not even meet on the same market. This paper argues that, instead of trying in vain to introduce a 'knock-out' system of competition in the EU Member States, a targeted approach might help raise productivity in lagging regions and thus improve the basis of competitiveness on global markets.     

Simulation of gas–solid two-phase flow in the annulus of drilling well

This paper investigates the hydrodynamic behavior of gas–solid two-phase flow in the annular space of an air drilling well under different arrangements by using three-dimensional approach. Two-fluid model is used to solve the governing equations in the Eulerian–Eulerian framework. Effect of eccentricity and drill pipe rotation on the pressure drop, volume fraction and velocity profile are examined. The results are compared with available data in the literature and good agreement is found. The results show that the presence of solid particles in the annulus change the air velocity profile significantly and create two off-center peaks velocity close to the walls instead of one peak velocity in the middle. Eccentricity of drill pipe makes more accumulation of the cuttings in the smaller space of the annulus. Increasing the eccentricity increases pressure drop due to impact of particles with annulus wall and also particles collision with each other. Rotation of the drill pipe shifts maximum air velocity location toward smaller space of the annulus which results more uniform cutting distributions in the annulus and improvement in their transportations. Pressure drop in the annulus increases as eccentricity and rotation of drill pipe increase.     

Unconfined compressive strength prediction of soils stabilized using artificial neural networks and support vector machines

This study aims to improve the unconfined compressive strength of soils using additives as well as by predicting the strength behavior of stabilized soils using two artificial-intelligence-based models. The soils used in this study are stabilized using various combinations of cement, lime, and rice husk ash. To predict the results of unconfined compressive strength tests conducted on soils, a comprehensive laboratory dataset comprising 137 soil specimens treated with different combinations of cement, lime, and rice husk ash is used. Two artificial-intelligence-based models including artificial neural networks and support vector machines are used comparatively to predict the strength characteristics of soils treated with cement, lime, and rice husk ash under different conditions. The suggested models predicted the unconfined compressive strength of soils accurately and can be introduced as reliable predictive models in geotechnical engineering. This study demonstrates the better performance of support vector machines in predicting the strength of the investigated soils compared with artificial neural networks. The type of kernel function used in support vector machine models contributed positively to the performance of the proposed models. Moreover, based on sensitivity analysis results, it is discovered that cement and lime contents impose more prominent effects on the unconfined compressive strength values of the investigated soils compared with the other parameters.     

Lu3+/Yb3+ and Lu3+/Er3+ co-doped antimony selenide nanomaterials: synthesis,characterization, and electrical,thermoelectrical, and optical properties

Lu³⁺/Yb³⁺ and Lu³⁺/Er³⁺ co-doped Sb₂Se₃ nanomaterials were synthesized by co-reduction method in hydrothermal condition. Powder X-ray diffraction patterns indicate that the Ln_xLn^′_xSb_2−2xSe₃ Ln: Lu³⁺/Yb³⁺ and Lu³⁺/Er³⁺ crystals (x = 0.00 − 0.04) are isostructural with Sb₂Se₃. The cell parameters were increased for compounds upon increasing the dopant content (x). Scanning electron microscopy and transmission electron microscopy images show that co-doping of Lu³⁺/Yb³⁺ ions in the lattice of Sb₂Se₃ produces nanorods, while that in Lu³⁺/Er³⁺ produces nanoparticles, respectively. The electrical conductivity of co-doped Sb₂Se₃ is higher than that of the pure Sb₂Se₃ and increases with temperature. By increasing the concentration of Ln³⁺ions, the absorption spectrum of Sb₂Se₃ shows red shifts and some intensity changes. In addition to the characteristic red emission peaks of Sb₂Se₃, emission spectra of co-doped materials show other emission bands originating from f-f transitions of the Yb³⁺ ions.     

Benchmark study of numerical methods for reliability-based design optimization

The reliability-based design optimization (RBDO) seeks for the best compromise between cost and safety, by considering system uncertainties. In order to overcome computational difficulties, many formulations have been recently developed, leading to confusion about what method should be selected for a given application, due to the lack of full-scale comparative studies. In this context, the present paper aims at giving an overview of various RBDO approaches which are tested on a benchmark constituted of four examples using mathematical and finite element models, with different levels of difficulties. The study is focused on the three main approaches, namely the two-level approach, the single loop approach and the decoupled approach; for each category, two RBDO formulations are discussed, implemented and tested for numerical examples. The benchmark study allows us to give comprehensive overview of various approaches, to give clear ideas about their capabilities and limitations, and to draw useful conclusions regarding robustness and numerical performance.     

Perimetric motion thresholds are elevated in glaucoma suspects and glaucoma patients

The purpose of this study was to determine if a clinically feasible perimetric motion test utilizing random-dot kinematograms could identify glaucomatous visual field defects. Using a staircase procedure, an automated perimetric motion test and a larger foveally presented target were given to normal (n = 30), glaucoma suspects (n = 31) and primary open-angle glaucoma patients (n = 19). Motion thresholds at specific locations throughout the whole visual field were significantly elevated in glaucoma patients (P < or = 0.001). Perimetric motion testing identified 84.2% of the primary open-angle glaucoma patients and 25.8% of the glaucoma suspects as abnormal. A larger foveal stimulus was unable to distinguish between the different subject groups (P < or = 0.185). Perimetric motion thresholds were significantly correlated with Humphrey standard visual field thresholds in the glaucoma and glaucoma-suspect patients (P < or = 0.0002).     

Integrated services for treatment of schizophrenic substance abusers: demographics, symptoms, and substance abuse patterns

We have previously described a model of outpatient integrated treatment for patients with comorbid psychoactive substance use disorders and schizophrenia (PSUD/S)(1). Here we review relevant literature on comorbidity and outline the rationale for integrated services. Further, we describe results from 3 related studies: First, we document the approximate incidence of PSUD among a heterogeneous group of 602 schizophrenic inpatient admissions to our hospital. Second, we describe in greater detail the psychiatric symptoms and patterns of substance abuse among a subsample of 106 inpatients with PSUD/S, contrasting them with 112 patients with PSUD and mixed psychotic disorders, but who are not schizophrenic. Third, we present a prospective research project and describe a sample of 30 patients with PSUD/S, detailing demographic characteristics, psychiatric symptoms and substance abuse history. Attention is given to current issues in the differential diagnosis of patients with PSUD/S using standardized instruments.     

Acral lentiginous melanoma

BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) may cause neuropathic bladder dysfunction due to spinal cord involvement. OPLL, unlike a traumatic spinal cord lesion, progresses insidiously and sometimes affects longer cord segments. As the manifestation of bladder dysfunction may depend on the development of OPLL, we studied the relationship between bladder function and roentgenographic changes in the spinal canals of OPLL patients. PATIENTS AND METHODS: Eighteen surgical candidates (11 males and 7 females, 34 to 85 years old) were studied urodynamically. Sixteen underwent CO2-filling cystometry, uroflowmetry and measurement of their residual urine volume. Cystometry was omitted in the remaining 2 patients. The vertical extent of OPLL and the degree of stenosis in the spinal canal was estimated by x-ray films and CT. RESULTS: The cystometric study revealed detrusor hyperreflexia in 2 patients and areflexic or underactive detrusors in 5 patients. Intermittent flows or considerable amounts of residual urine were also observed in the arefilexia/underactive group. Uroflowmetry showed a normal flow with little residual urine in both patients in whom cystometry was omitted. Bladder sensation was maintained in all patients. The occurrence of abnormal detrusor activity had no relationship to the degree of canal stenosis, while the occurrence of an areflexic or underactive detrusor correlated with the vertical extent of OPLL. CONCLUSION: Although detrusor hyperreflexia is common in an upper spinal cord lesion, attention should also be paid to the development of detrusor underactivity in patients with a wide vertical extent of OPLL.     

Molecular characterization of Borrelia burgdorferi sensu lato from Slovenia revealing significant differences between tick and human isolates

The aim of the study was to evaluate the morphological and functional status of the liver in acute, oral cholinesterase inhibitors poisoning using static scintigraphy, hepatography and measurements of chosen enzymes activity. Considering the different clinical picture of cholinesterase inhibitors poisonings in people, it was necessary to estimate the poisoning severity and its dependence on the frequency and intensification of the liver lesion. Under examination there were 37 cholinesterase inhibitors orally poisoned patients, treated at the Department of Toxicology in the years 1992-1995. The examined group comprised 7 women (19%) and 30 men (81%). Organophosphate compounds poisoning was noted in 14 patients, and carbamates poisonings in 23 patients. The reference group comprised 30 healthy men aged 24 to 59 years not exposed to hepatotoxic agents. More than 90% of patients were classified as severe poisoned. Any fatal case was not noted. A differently intensified pathological changes of the liver dependent on age and poisoning severity were found in 97.2% of patients and their frequency was significantly higher than in the control group. Hepatographic picture revealed in 96.6% of cases the liver lesion. Hepatographic picture of the liver was also dependent on poisoning severity. The higher activity of AST, ALT, AP and higher bilirubin concentration in blood were noted in poisoned men compared to the control group. Control scintigraphic examination revealed a considerable improvement in the intensification of the liver scintigraphic picture in 40% of the patients and a higher intensification in 13% of the subjects. In 46.6% of the patients the intensification of scintigraphic changes remained at the same level. Considering arbitrary criteria for the degree of the liver lesion, the improvement in the intensification of hepatographic changes was noted in 42.8% of the patients; the intensification of the liver lesion was not noted even in one case. Analyzing the percentage of the liver lesion for each individual patient, improvement was noted in 92.8% of the examined patients, and the changes with the same level of intensification in 7.2%. Deterioration was not noted at all. Conclusion: The liver scintigraphy and hepatography combined with biochemical analysis allows to assess the liver condition in acute cholinesterase inhibitors poisoning.