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Al-Mg alloys used in the shipbuilding industry were tested. The most commonly used alloy AW 5083 and alloy AW 5059 with higher strength properties were selected. Both native materials and their joints welded by the traditional MIG arc welding method and the friction stir welding (FSW) method were tested. Both methods are approved by classification societies which allow them to be used in construction by the shipbuilding industry. The research was carried out in two stages. The first study was an "in-situ tensile test in SEM". The surfaces of the deformed specimens' changes were observed in the vacuum chamber of a Philips XL30 scanning electron microscope. During the tests, the force and elongation of the specimen were recorded. In addition, a chemical analysis of selected precipitates was performed by energy dispersive spectrometry (EDS) using the EDAX adapter. Slip lines were observed on the surface of the tested specimens, which are arranged in bands in the native material and in a disordered manner in the joints welded by MIG and FSW methods. Cracking starts mainly through decohesion at the matrix-precipitate interfaces. In the second stage of the research, slow strain rate testing (SSRT) was carried out in accordance with ISO 7539-7:2005. The tests were carried out on a specially designed test stand, where the FT-5307 strain gauge force sensor with a measuring range of 0-16 kN was used to measure the force value. The PSz 20 transducer with a measuring range of 0-20 mm was also used. The test consisted of subjecting the specimen to increasing deformation with the strain rate έ = 1.6 × 10 -6 s -1 until destruction. The fracture surfaces of the SSRT specimens were subjected to fractographic analysis using a Philips XL-30 scanning electron microscope. The results of fractographic studies after the SSRT test of the native materials and their joints welded by the MIG and FSW methods indicate that the trans-crystalline cracking mechanism is dominant, characterized by ductile fracture, and cracks are initiated at the interfaces of the precipitates with the matrix. The research results show that the plastic deformation increases and micro-cracks develop and merge into a main crack, which, after reaching the critical dimension, rapidly develops, causing the destruction of the material. The fracture micrographs of the specimens of base metals and their joints welded by FSW and MIG after the SSRT test allow us to conclude that the cracking mechanism was trans-crystalline ductile.

The ongoing shift towards hybrid and electric vehicles has a strong impact on noise and vibration engineering. New, complex dynamic phenomena are brought to vehicle user attention due to the absence of internal combustion engines and the significant role in vehicle and drive feel perception. This paper presents an FEM (Finite Element Method) dynamic simulation model of an automotive Electric Power Steering assembly. Preliminary modal simulations and experiments as well as field data replication techniques were implemented to identify the phenomena and prepare and validate model components. A full dynamic model of an Electric Power Steering was presented, and fine-tuned including the presence of lubrication at the gear mesh interface. Experimental investigations were conducted alongside FEM simulations for various model setups. Linear and nonlinear contact stiffness models were implemented, as well as contact damping, and simulated at chosen assembly interfaces. The results indicated that in the case of NVH (Noise Vibration and Harshness) analysis of shock/impact originating problems, contact parameters used for static, quasi-static, and low velocity analyses were not applicable. Nonlinear and damped contact stiffness provided better results in such a case.

Sport does not automatically generate educational benefits for players. For a sports field to become a child-friendly educational environment, it is essential that all actors involved in the organization of youth sport take deliberate educational measures. Among these actors are referees, who should be taken into account during the research on the educational value of sport for the youngest. The subject of the present study was handball referees, who interact with the players during matches. Assuming that the referee is an important actor in sport education and that referee-players interactions are the basic mechanism of the referee's educational influence, this study aimed to assess the quality of his or her interactions with players during handball matches for children aged 9 to 12 years. The research was conducted in a group of 25 handball referees who refereed matches of children in the region of Mazowieckie Voivodeship in Poland. The referees surveyed had current licenses issued by the Warsaw-Mazovian Handball Association. To assess the quality of referee-players interactions, the authors' direct observation tool (Referee-Players' Interaction Assessment Scoring System) was used. The educational referee-players interaction was studied in six dimensions: Positive climate, Responsiveness, Behavior management, Proficiency, Instructing, and Communicating. Data were statistically analyzed using chi-squared test, Mann-Whitney U test and exploratory factor analysis (EFA). Cronbach's alpha values were higher than 0.90 in the factors, showing adequate levels of reliability. The results of the research demonstrated that the assessment of the quality of the referee's educational influence on players was neither affected by the referees' experience nor by the outcome of the match. The quality of educational referee-players interactions in five of the six dimensions studied was assessed as average, whereas positive climate was assessed as poor (three-step scale: poor, average, good). If referees are to support coaches and parents in achieving their educational goals, the results indicate areas where they can improve. The research provided empirical evidence that could be used as a basis for the modification of previous training programs for referees developed by local and national sports associations. The referees should be trained to build a positive climate on the sport field, which consists in creating emotional ties with players (physical proximity, social conversation), expressed in an enthusiastic attitude and joy of contacts (smiling, engagement, positive affect reaction, positive comments, respectful and inclusive language, using players first names, listening to players). In addition, referees must be taught to actively monitor players' emotional, cognitive, social, and health needs, as well as to respond to the players' needs and solve problems.

We assume that all institutions and individuals involved in the organization of sport for children and young people should utilize the educational potential of sport. We assessed the quality of referee interactions with children during sports competitions in soccer. Based on the developmental theory and research suggesting that interactions between kids and adults are the primary mechanism of their development and learning, we focused on the quality of the referee-player interactions in terms of (1) emotional support, (2) game organization, and (3) instructional support. Twenty-five soccer referees who refereed matches for children aged 9-12 years were recruited. The Referee Educational Function Assessment Scoring System (REFASS) was used to assess the quality of the referee-player interactions. This tool was developed based on Classroom Assessment Scoring System-Upper Elementary. Regarding the REFASS dimensions, the mean scores for positive climate, Sensitivity, behavior management, content understanding and quality of feedback were in the medium range, while productivity and negative climate in the high range. In the case of the positive climate variable, the lowest mean ratings were recorded compared to other assessed dimensions. The assessments of the quality of referee-player interactions obtained for particular dimensions translated into the ratings for the specified domains. The highest ratings were given to game organization (6.0 ± 0.8; Me = 6.0), whereas the emotional support and instructional support were in the medium range (4.6 ± 1.5; Me = 4.5, and 5.2 ± 1.8; Me = 6.0, respectively). Referees are usually not aware of their pedagogical function and the complexity of their respective responsibilities. They are commonly considered to be ordinary technicians and evaluators of performance in competition. Based on the results, a postulate was formulated that referees should consciously perform a pedagogical function in the youth sport. Therefore, it is necessary to train them in educational methods and techniques appropriate to the age and needs of the child. The referees will then be prepared to take actions to prevent negative behavior of players on the field and to encourage prosocial behavior., Competing Interests: The authors declare no conflict of interest.

Optical thin section observations represent the core empirical basis for most micromorphological interpretations at archaeological sites. These observations, which often vary in size and shape, are usually documented through digital graphic representations such as photomicrographs, scans, or figures. Due to variability in documentation practices, however, visual thin section data can be captured with a range of methods and in many different formats and resolutions. In this paper, we compare and evaluate five common image-based methods for documenting thin sections in high-resolution: a flatbed scanner, a film scanner, a macro photography rig, and conventional stereo and light microscopes. Through the comparison results, we demonstrate that advances in digital imaging technology now allow for fast and high-resolution visual recording of entire thin sections up to at least ×30 magnification. We suggest that adopting a digital micromorphological documentation practice has several advantages. First, a digital thin section may be observed more efficiently and consistently, for example, on a computer screen, and the spatial configuration of large or complex features may be more accurately documented. Second, they allow for the establishment of digital repositories that may promote scientific reproducibility and inter-laboratory communication, as well as lay the foundations for more consensus-based educational training of archaeological micromorphology.

Objectives: The aim of this research was to examine whether Perfusion Computed Tomography (P-CT) can qualitatively and quantitatively help detect gastric cancer neoangiogenesis in vivo as well as treatment response evaluation. We attempted to explore which P-CT parameters are best used in neoangiogenesis and neoadjuvant therapy for most effective evaluation. We also tried to recognize a positive prediction value of P-CT in early responders and non-responders patients identification., Materials and Methods: Twenty-four patients with positive biopsy results and/or clinically proven gastric cancer were enrolled in the P-CT exam. Patients were qualified for systemic treatment (16 patients received chemotherapy and 8 patients received radiochemotherapy). The baseline Perfusion-CT exam and after neoadjuvant treatment Perfusion-CT exam were conducted using a 64-row GE tomograph based on a deconvolution model in first-pass protocol perfusion. The P-CT examined the following parameters: Blood Flow (BF), Blood Volume (BV), Mean Transit Time (MTT) and Permeability Surface (PS). Positive clinical response to neoadjuvant treatment (CHT and RCT) was defined as tumor size reduction 25% or more., Results: Tumor dimension reduction after neoadjuvant therapy was significantly correlated with the BF and the PS. Neoadjuvant therapy was more effective for patients with higher output BF and PS values. We did not register a significant relationship between BV and MTT parameters and tumor dimension reduction. Patients with a positive treatment response showed a decrease in BF, BV and PS perfusion parameters with an increase in MTT., Conclusions: P-CT examination allows a noninvasive neoangiogenesis assessment in vivo, leading to early identification of responding and non-responding patients. As a standard procedure, a full evaluation of treatment response should include a P-CT exam assessing neoangiogenesis., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The Minister of National Education introduces relevant changes into the content and aims of health education in virtue of the resolution of 23 December 2008 that relates to the essential curricula of pre-school and general education in particular types of schools. Special responsibility for the realization of the health education programme in schools rests, according to the content of the above mentioned document, with the teachers of physical education. Placing physical education teachers in the role of the leading executor of the health education aims in schools induces a reflection on the degree of the teachers'preparation to fulfill such a role. In order to carry out such evaluation it is essential to determine more accurately the scope of competences, which are requisite of an efficient realization of health education in conditions appropriate to school physical education. In the study we work on the characteristics of the subject competences and of the pedagogical competences of the physical education teacher, which are indispensable in the effective realization of the health education programme. As far as the first competences we focus on the knowledge and didactic and organizational skills which a physical education teacher should possess, and as far as the second competences we discuss five categories of competences: moral, praxiological, communicational, creative and informative.

Background: The mortality in aortic abdominal aneurysm surgery remains in the 2-7% range. The aim of the study was to compare the results and safety of surgical aneurysm resection with grafting under general anaesthesia, using percutaneous insertion of a stent under local anaesthesia and intravenous analgesic sedation., Methods: The data from patients scheduled for elective subrenal abdominal aortic treatment was analysed retrospectively. Patients were allocated to two groups, according to their general condition, ASA status, presence of other pathologies and anatomical conditions. Patients in group I underwent open surgery with general anaesthesia; patients in group II received stents implanted using local anaesthesia and intravenous analgesic sedation., Results: One houndred twenty-seven patients were allocated either to group I (n=87) or to group II (n=40). Blood pressure, heart rate, the need for catecholamines, blood loss and fluid replacement were all higher in group I. More than 50% of patients from this group required mechanical ventilation in the early postoperative period, as well as longer hospitalization. All patients in group II survived, while 6 patients from group I died from postoperative complications., Conclusions: Endovascular repair of aortic abdominal aneurysms under local anaesthesia combined with i.v. sedation is a safe alternative in high-risk patients.

Respiratory distress and the need for mechanical ventilation, have been the most common reasons for ITU hospitalization. Pulmonary pathology is sometimes difficult to diagnose and differentiate; therefore we are on a continuous search for diagnostic tools and markers. It has been suggested that in patients intubated for acute lung injury, lower concentrations of surfactant proteins A and D in bronchoalveolar fluid and higher concentrations in the plasma are associated with more severe lung injury and worse clinical outcomes. Surfactant protein D (SP-D) plays a crucial role in defense mechanisms and immunomodulation, binding with various pathogens such as bacteria, fungi and viruses. SP-D is a valuable marker in ARDS and other specific and non-specific pulmonary pathologies, and may find a place as a valuable marker of the severity of disease.

Gastric tonometry is relatively non-invasive technique to assess gastric perfusion and to monitor oxygen metabolism in visceral system. The technique utilizes the PCO2 of the gastric fluid to calculate intramucosal pH (pHi). The calculation is assessed by a modified Henderson-Hasselbalch equation. The combination of a high intramural PCO2 and mucosal acidosis may result from decreased splanchnic perfusion. The values of pHi and regional PCO2 (PrCO2) based on gastric tonometry reflect indirect index of visceral blood flow. In clinical practice the PCO2 of the gastric fluid is collected from saline sampled in the penetrable by carbon dioxide balloon. The silicon balloon is a part of tonometric probe placed in the gastric lumen. Device TONOCAP (Datex-Ohmeda, Helsinki, Finland) allows for full automatic measurement of the carbon dioxide regional pressure (PrCO2). Presented experimental and clinical studies confirmed the usefulness of gastric tonometry in visceral blood perfusion assessment during perioperative and critical ill stage. Finally, the technique allows to decrease the number of complications, treatment expenses and mortality.

Endothelial dysfunctions in the microcirculation are a common finding in the course of inflammatory disorders. These are, at least in part, mediated by endogenous agonists, e.g. tumor necrosis factor-alpha (TNF-alpha). As TNF-alpha mostly acts in an autocrine or paracrine fashion, it was tempting to speculate that microvascular endothelial cells synthesize and release this cytokine upon appropriate stimulation. In the present study, human dermal microvascular endothelial cells (HDMECs) expressed the TNF-alpha gene following incubation with interleukin-1beta (IL-1beta), lipopolysaccharids (LPSs), as well as a combination of IL-1beta, LPSs, and interferon-gamma (IFN-gamma), while IFN-gamma failed to exert an effect on TNF-alpha gene expression when given as a single stimulus. Transcription of the TNF-alpha gene was accompanied by an increase in TNF-alpha protein secretion into the cellular supernatant. As HDMECs were found to be a target of TNF-alpha, production of this cytokine by HDMECs may result in an autocrine activation loop that contributes to the deterioration of microcirculatory functions in infectious diseases and inflammatory skin disorders.

Objective: Elevated procalcitonin concentrations are found in the course of systemic inflammation caused by bacterial insults, for example, sepsis and septic shock. However, the source of procalcitonin and its role in the inflammatory process are still unknown. In clinical studies, procalcitonin concentrations reflected the severity of sepsis and were predictive of mortality, suggesting that an increased procalcitonin synthesis is detrimental for the host. In contrast, and data report anti-inflammatory effects of procalcitonin that rather may represent a benefit for the septic patient., Design: Prospective, controlled, cell culture study., Setting: University research laboratories., Subjects: WKY rats., Interventions: We investigated whether procalcitonin affects one principal mediator of sepsis, inducible nitric oxide synthase-derived nitric oxide, taking into account the typical 3-hr delay of procalcitonin increase following a bacterial challenge. Vascular smooth muscle cells were incubated with lipopolysaccharide (10 microg/mL), tumor necrosis factor-alpha (500 units/mL), interferon-gamma (100 units/mL), and procalcitonin (1, 10, 100, and 1000 ng/mL). Cells were preincubated with lipopolysaccharide for 90 mins followed by the addition of tumor necrosis factor-alpha/interferon-gamma. In a second set of experiments, procalcitonin was added to these proinflammatory agonists 3 hrs after lipopolysaccharide application., Measurements and Main Results: Although no inducible nitric oxide synthase complementary DNA was detectable in unstimulated controls and following single application of procalcitonin, inducible nitric oxide synthase gene expression was induced in cells treated with lipopolysaccharide plus tumor necrosis factor-alpha/interferon-gamma for a total incubation time of 24 hrs. When vascular smooth muscle cells were incubated with procalcitonin in addition to lipopolysaccharide plus tumor necrosis factor-alpha/interferon-gamma, a further stimulation of inducible nitric oxide synthase transcription rate could be detected., Conclusions: These results provide evidence that procalcitonin acts as a modulator that augments the inflammatory response triggered by agonists like lipopolysaccharide, tumor necrosis factor-alpha, and interferon-gamma. Although not effective as a single stimulus, it might contribute to the detrimental outcome following excessive activation of the inflammatory cascade.

In the course of sepsis, severe coagulopathy and disseminated intravascular coagulation (DIC) are common events. Therefore, substances known to interfere with the coagulation cascade have been studied in animal models of sepsis. Among them, antithrombin III (AT III) was reported to be a promising therapeutic tool because it exhibited anti-inflammatory properties in addition to its anticoagulative effects. In our studies using vascular smooth muscle cells (VSMC) as a monoculture model, contradictory effects of AT III on the release of the proinflammatory agonists tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) were found. Whereas AT III inhibited the lipopolysaccharide (LPS)-induced production of these cytokines on both the transcriptional and the translational levels when given at higher concentrations (5 or 10 U/ml), lower amounts of AT III did not show this suppressive effect. In contrast, 0.5, 1, and 5 U/ml AT III led to an enhancement of TNF-alpha synthesis when combined with LPS. To date, we cannot provide a mechanism to explain the AT III-promoted modulation of TNF-alpha and IL-1beta generation in VSMC. However, with respect to its potential therapeutic benefit in systemic inflammatory conditions, AT III should not be regarded strictly as an anti-inflammatory modulator.

Objective: In a recent study, we found different profiles of inducible nitric oxide synthase (iNOS) gene expression in the ovarian carcinoma cell lines OVCAR-3, HOC-7, and 2774 following stimulation by proinflammatory cytokines. The present study was performed to determine whether nitric oxide (NO) synthesis correlates with programmed cell death in these cells., Methods: NO-Dependent apoptosis was detected by DNA fragmentation analysis and fluorescence-activated cell sorter analysis., Results: NO formation in response to interferon gamma (IFN-gamma), interleukin-1beta (IL-1beta), and tumor necrosis factor alpha (TNF-alpha) was correlated with programmed cell death in the investigated cells. DNA fragmentation was most prominent in OVCAR-3 (34.17 +/- 1.81%), less pronounced in HOC-7 (12.86 +/- 0.45%), and undetectable in 2774 (4.54 +/- 0.40%) cells. The rate of apoptosis correlated with the amount of NO formation in cytokine-treated cells. Moreover, coincubation of OVCAR-3 and HOC-7 with the specific iNOS inhibitor aminoguanidine suppressed apoptosis induced by IFN-gamma, IL-1beta, and TNF-alpha., Conclusion: Our data indicate that in OVCAR-3 and HOC-7 cells, NO synthesis induced by IFN-gamma, IL-1beta, and TNF-alpha is correlated with the degree of apoptotic cell death. In clinical situations, this might in part explain the benefit of cytokine application in ovarian carcinoma patients (e.g., documented for IFN-gamma)., (Copyright 2001 Academic Press.)

Evidence suggests that antithrombin III (ATIII) exerts anti-inflammatory properties in addition to its anti-coagulative mechanisms. In animal models of sepsis, ATIII affected cytokine plasma concentrations with a decrease of pro-inflammatory cytokines. In addition to cytokines, excessive production of nitric oxide (NO) derived from inducible nitric oxide synthase (iNOS) might represent another important mediator of the cytotoxic events during sepsis. Regarding ATIII as a potential anti-inflammatory modulator, one may speculate that ATIII inhibits the synthesis of iNOS-derived NO. However, our data demonstrate that ATIII further stimulates iNOS gene expression when applied together with either interleukin-1 beta or the combination of lipopolysaccharide plus interferon-gamma. The most prominent synergistic effects on NO synthesis were found when ATIII was given at higher concentrations (1, 5, and 10 U/ml). Although the mechanisms of ATIII signal transduction remain to be established, intensification of interleukin-1 beta or interferon-gamma/lipopolysaccharide-induced NO synthesis by ATIII does not attribute to the anti-inflammatory properties of ATIII., (Copyright 2001 Academic Press.)

A soluble [NiFe] hydrogenase has been partially purified from the obligate thermophilic sulfate-reducing bacterium Thermodesulfobacterium mobile. A 17% purification yield was obtained after four chromatographic steps and the hydrogenase presents a purity index (A398 nm/A277 nm) equal to 0.21. This protein appears to be 75% pure on SDS-gel electrophoresis showing two major bands of molecular mass around 55 and 15 kDa. This hydrogenase contains 0.6-0.7 nickel atom and 7-8 iron atoms per mole of enzyme and has a specific activity of 783 in the hydrogen uptake reaction, of 231 in the hydrogen production assay and of 84 in the deuterium-proton exchange reaction. The H2/HD ratio is lower than one in the D2-H+ exchange reaction. The enzyme is very sensitive to NO, relatively little inhibited by CO but unaffected by NO2-. The EPR spectrum of the native hydrogenase shows the presence of a [3Fe-4S] oxidized cluster and of a Ni(III) species.

A partially-purified sample of hydrogenase from Methanobacterium thermoautotrophicum (delta H strain) has been investigated by optical absorption, magnetic circular dichroism and electron paramagnetic resonance spectroscopy. Variable temperature magnetic circular dichroism studies reveal, for the first time, the optical transitions associated with the Ni(III) center in the oxidized enzyme. Low temperature magnetic circular dichroism spectroscopy provides a new method of assessing both the coordination environment of Ni in hydrogenase and the appropriateness of inorganic model complexes.

The effect of low concentrations of CO (0.93 - 5.58 microM) on the EPR spectrum of the periplasmic non-heme iron hydrogenase from D. vulgaris has been investigated. The "g = 2.06" EPR signal is maximally induced (0.94 spin/molecule) at 46.5 microM CO and partial induction of the EPR signal could be observed at 0.93 microM CO. This effect is reversed by removal of the CO or irradiation of the hydrogenase with white light.

A hydrogenase from a new species of sulfate reducing bacterium has been isolated and characterized. In contrast to other hydrogenases isolated from Desulfovibrio, this enzyme is found in the cytoplasmic fraction rather than in the periplasm. The specific activity of the enzyme, as measured in the hydrogen evolution assay, is twice as high as the specific activity of the hydrogenase from D. gigas. It also differentiates itself from the periplasmic Desulfovibrio hydrogenases by being more active in the hydrogen evolution rather than in the hydrogen uptake assay. The enzyme was shown to contain 0.9 atoms of nickel, 11 atoms of iron and 10 atoms of labile sulfide per mole of enzyme. It exhibits an unusually low intensity of the g = 2.31 nickel EPR signal in the isolated enzyme but shows a normal intensity for the g = 2.19 nickel EPR signal when reduced under hydrogen.