bluuebunny/crossref_metadata_2025 huggingface dataset:
Hemoglobin aggregates studied under static and dynamic conditions involving the formation of nanobacteria-like structures
Authors: Baum Jeramy , Jones Riland , Manning Thomas , Nienow James , Phillips Dennis
Published: June 2012

Hemoglobin aggregates studied under static and dynamic conditions involving the formation of nanobacteria-like structures

Laser light scattering and scanning electron microscopy (SEM) are used to study hemoglobin in the aqueous phase. The impact that salts [NaCl, Ca3(PO4)2] and iron oxide nanoparticles have on the hemoglobin size are also studied. The first set of experiments examined hemoglobin aggregates in the aqueous phases in the presence of salts and nanoparticles. Aqueous phase samples were then dehydrated and examined using SEM. The resulting structures resemble those observed in nanobacteria studies conducted in other labs. This study demonstrates that aggregates of hemoglobin and various salts found in a physiological environment can produce structures that resemble nanobacteria.
Immunomodulatory effects of anti-estrogenic drugs
Authors: Ray Amitabha , Ficek Monica
Published: June 2012

Immunomodulatory effects of anti-estrogenic drugs

There are substantial experimental, epidemiological and clinical evidences that show that breast cancer pathology is influenced by endogenous estrogens. This knowledge is the foundation upon which endocrine deprivation therapy has been developed as a major modality for the management of breast cancer. Tamoxifen, which functions as a competitive partial agonist-inhibitor of estrogen at its receptor, has been widely used for more than three decades for adjuvant endocrine treatment in breast cancer. Currently, other effective drugs for endocrine therapy include raloxifene, different aromatase inhibitors (particularly third-generation agents) and luteinizing hormone-releasing hormone agonists. In recent years, a growing body of evidence suggests that these drugs can also act as immune modulators by altering the function of various leukocytes and the release of different cytokines. Moreover, there is evidence that anti-estrogens may prove to be beneficial in the treatment or prevention of some autoimmune diseases due to their effects on immune function. However, their immunopharmacological aspects in the present state of knowledge are not precisely comprehensible. Only a clear pathophysiological understanding could lead to an efficient strategy for breast cancer prevention and decrease in the mortality due to this disease.
Culture conditions and salt effects on essential oil composition of sweet marjoram (Origanum majorana) from Tunisia
Authors: Baâtour Olfa , Tarchoune Imen , Mahmoudi Hela , Nassri Nawel , Abidi Wissal , Kaddour Rym , Hamdaoui Ghaith , Nasri-Ayachi Mouhiba , Lachaâl Mohtar , Marzouk Brahim
Published: June 2012

Culture conditions and salt effects on essential oil composition of sweet marjoram (Origanum majorana) from Tunisia

O. majoranashoots were investigated for their essential oil (EO) composition. Two experiments were carried out; the first on hydroponic medium in a culture chamber and the second on inert sand in a greenhouse for 20 days. Plants were cultivated for 17 days in hydroponic medium supplemented with NaCl 100 mmol L-1. The results showed that theO. majoranahydroponic medium offered higher essential oil yield than that from the greenhouse. The latter increased significantly in yield (by 50 %) under saline constraint while it did not change in the culture chamber. Under greenhouse conditions and in the absence of salt treatment, the major constituents were terpinen-4-ol andtrans-sabinene hydrate. However, in the culture chamber, the major volatile components werecis-sabinene hydrate and terpinen-4-ol. In the presence of NaCl, new compounds appeared, such as eicosane, spathulenol, eugenol, and phenol. In addition, in the greenhouse, with or without salt, a very important change oftrans-sabinene hydrate concentration in EO occurred, whereas in the culture chamber change appeared incis-sabinene hydrate content.
Econometric Analysis of the Impact of Propensities on Economic Occurrences: A Macroeconomic Perspective
Authors: Doszyń Mariusz
Published: June 2012

Econometric Analysis of the Impact of Propensities on Economic Occurrences: A Macroeconomic Perspective

The main aim of this article was the specification of problems connected with analysis of impact of human propensities on economic occurrences and also a proposition of econometric tools enabling the identification of this impact. According to the meaning of propensities in economics the current state of knowledge is mostly an effect of considerations presented by J.M. Keynes in his famous book "The General Theory of Employment, Interest and Money" where J.M. Keynes proposed such economic categories as the average and marginal propensities. One of the goals of the presented deliberations was to specify problems related with economic theory of propensities. Such propensities as a propensity to consume, to save, to invest and thesaurisation were particularly carefully analysed. The impact of these propensities on basic macroeconomic variables was considered with respect to the classical model, the neoclassical Solow-Swan model and theIS-LMscheme. In case of spatial data the effects of the impact of propensities could be analysed by means of models with dummy variables showing presence of given propensities. A procedure enabling the construction of such variables was proposed. In case of time series, conceptions delivered by the integration and cointegration theory could be applied. Especially such models as VAR and VECM could be useful. Models for panel data enable direct (models with fixed effects) or indirect (models with random effects) consideration of the impact of propensities on the analysed processes.
Arch Effects in Multifactor Market-Timing Models of Polish Mutual Funds
Authors: Olbryś Joanna
Published: June 2012

Arch Effects in Multifactor Market-Timing Models of Polish Mutual Funds

Performance measurement of investment managers is a topic of interest to practitioners and academics alike. The traditional performance evaluation literature has attempted to distinguish stock-picking ability (selectivity) from the ability to predict overall market returns (market-timing). However, the literature finds that it is not easy to separate ability into two such dichotomous categories. To overcome these problems multifactor alternative market-timing models have been proposed. The author's recent research provides evidence of strong ARCH effects in the market-timing models of Polish equity open-end mutual funds. For this reason, the main goal of this paper is to present the regression results of the new GARCH(p, q) versions of market-timing models of these funds. We estimate multifactor extensions of classical market-timing models with Fama & French's spread variables SMB and HML, and Carhart's momentum factor WML. We also include lagged values of the market factor as an additional independent variable in the regressions of the models because of the pronounced "Fisher effect" in the case of the main Warsaw Stock Exchange indexes. The market-timing and selectivity abilities of fund managers are evaluated for the period January 2003-December 2010. Our findings suggest that the GARCH(p, q) model is suitable for such applications.
On Certain Analogies Between the Laws of Quantum Mechanics and Rules of an English Auction
Authors: Drabik Ewa
Published: June 2012

On Certain Analogies Between the Laws of Quantum Mechanics and Rules of an English Auction

It is a self-evident truth that nowadays a growing number of economic phenomena is described by means of physics methods. The most frequent theories derived from physics and applied to economy are: (1) the universal gravitation law and (2) the first as well as the second law of thermodynamics. The methods of static physics are applicable also to the theory of financial markets. In this case it is assumed that the financial market is composed of single participants interacting as a system of particles. Such approach is associated with a model of financial market otherwise known as a minority game. It is postulated that the process of securities and money allocation is performed on the basis of prices fluctuation, where - if a vast majority of investors tend to purchase goods or services - the sale constitutes a more profitable option, and vice versa. The players who end up on minority side win. At the end of the XX century the economy commenced to apply the laws of quantum mechanics. These laws proved to be useful, in particular when attempting to generalize game theory, which resulted in quantum games. The aim of the paper is to compare the rules and auction mechanisms with selected laws of quantum mechanics. This paper aims also to introduce the basic concepts of quantum mechanics to the process of economic phenomena modeling. Quantum mechanics is a theory describing a behaviour of microscopic objects and is grounded on the principle of wave-particle duality. It is assumed that quantum-scale objects at the same time exhibit both wave-like and particle-like properties. The key role in quantum mechanics is played by: (1) the Schrödinger equation describing the probability amplitude for the particle to be found at a given position and at a given time, as well as (2) the Heisenberg uncertainty principle stating that a certain pair of physical properties may not be simultaneously measured to arbitrarily high precision.
Changes in body build of awf students 1967–2008. Can a secular trend be observed?
Authors: Stachoń Aleksandra , Burdukiewicz Anna , Pietraszewska Jadwiga , Andrzejewska Justyna
Published: June 2012

Purpose

Previous research on intergenerational changes in body build has focused on body height and mass. The aim of this study was to determine both the direction and sexual dimorphism of secular changes in body build by using a sample population of students attending the University School of Physical Education (AWF) in Wrocław, Poland.

Methods

The anthropometric data used in this study were collected every year from 1967 to 2008 and included a sample size of 4688 males and 3922 females. The subjects were analyzed for changes in somatotype by use of Sheldon’s method, as modified by Heath and Carter. Basic statistical analysis for significance and post-hoc tests were used to analyze the data with Statistica 9.0 software. The data were then converted in Excel 2003 into chart form to analyze the direction of changes.

Results

Analysis of the successive classes of male and female subjects during the 40-year period under study revealed a number of different directional changes in the mean values of body height, mass and the level of body build components. Trend lines, calculated by the mean values of five-year intervals, indicated an increasing tendency in both body height and mass in the two genders. Mesomorphy was found to be the largest factor of body build composition of females and males. Throughout the entire analyzed period, the endomorphy of males was significantly lower in comparison to females. In women, the level of fatness was similar to their level of musculature, but during the last several years the observed level of muscle in the students exceeded their fatness level. Ectomorphy happened to be the most stable component of both sexes.

Conclusions

Analysis on the male and female sample population revealed a constant increase in body mass and height in successive generations. In female subjects, intergenerational changes were found to be characterized by a decrease in endomorphy and an increase in ectomorphy, while the level of mesomorphy remained at a similar level. In men, a secular trend was visible with an increase in mesomorphy, while the levels of endomorphy and ectomorphy stayed constant.
Health-related physical fitness and associated sociodemographic factors in adolescents from a brazilian state capital
Authors: Petroski Edio Luiz , Silva Diego Augusto Santos , Silva João Marcos Ferreira de Lima E , Pelegrini Andreia
Published: June 2012

Purpose

The aim of this study was to investigate the associations between health-related physical fitness and sociodemographic factors in students from a capital city of a Brazilian state.

Methods

A cross-sectional study was conducted on 605 students aged 15 to 19 years. Sociodemographic data were collected, including gender, age, education level and family income, and correlated to physical fitness levels.

Results

The percentages of students with unhealthy body composition, unhealthy skeletal muscle fitness and aerobic fitness levels were 23.8%, 34.4% and 30.5%, respectively. There was a trend for fewer male adolescents (OR: 0.65; IC95%: 0.42–0.98) to have unhealthy body composition. Students from lower socioeconomic families were less likely to have musculoskeletal unfitness (OR = 0.60; IC95%: 0.41–0.89). In relation to aerobic fitness, male students (OR = 3.86; IC95%: 2.67–5.58) and those aged 17–19 years (RO = 1.49; IC95%: 1.02–2.177) were more likely to be unfit.

Conclusions

It is important to encourage young people to take part in sports and physical activities at moderate to vigorous intensities in order to improve their body composition, aerobic capacity and physical fitness.
Selected psychological determinants of sports results in senior fencers
Authors: Tomczak Maciej , Walczak Małgorzata , Bręczewski Grzegorz
Published: June 2012

Purpose

The aim of the present study was to determine the correlations between the strength of the stimulation process, mobility of nervous processes, achievement motivation and sports results of fencers in the senior age category.

Methods

The sample was comprised of 38 senior fencers (19 men and 19 women) aged 21–32 years. The strength of the stimulation process and mobility of nervous processes were assessed with the Strelau and Zawadzki PTS inventory. The subjects’ achievement motivation was measured with the achievement motivation questionnaire by Widerszal-B azyl.

Results

The study revealed that senior fencers (women, in particular) featured higher mean levels of the examined psychological determinants, i.e., strength of the stimulation process, mobility of nervous processes and achievement motivation than the general population in the same age range. Strong and statistically significant correlations were found between all the studied psychological determinants and sports results among the male fencers in the sample. In the group of female fencers none of the correlations were statistically significant.

Conclusions

The results might provoke reflection on the role of coaches and, consequently, may have implications for the cooperation between coaches and athletes, indicating that the individual psychological differences of fencers should be considered during training. The coach may also decide on the necessity for considering on the reported diversification within the gender or age domain, and the need to consider such psychological properties as temperamental characteristics or the level of achievement motivation.
Mood changes in individuals who regularly participate in various forms of physical activity
Authors: Myrna-Bekas Renata , Kałwa Małgorzata , Stefaniak Tadeusz , Kulmatycki Lesław
Published: June 2012

Purpose

A number of mental and physical benefits arise from leading an active lifestyle. Many forms of therapies make use of physical activity to reinforce rehabilitation as well as improve the condition of the body and mind. It is in this way that an individual can improve their well-being through cleansing the body of negative emotions and seek inner harmony, which is one of the most important features of mental health. However, the question arises whether all forms of physical activity improve the emotional state of an individual in the same way. A qualitative change in mood may be in fact related to the methodical factors present in physical activity (the type of exercise, the training method or its intensity and frequency) but also an instructor’s personality, the age and gender of the participant as well as their physical fitness and motor skills, the subject’s current social and mental state, environmental factors or other factors related to everyday life such as work, family, etc. The aim of this study was to determine the changes in mood of physically active and highly fit people, aged 22–25 years, after various forms of physical activity and with different training methodologies.

Methods

The Mood Adjective Check List (UMACL) was administered to 84 students before and after completing a course in a number of physical activities. Statistical methods were then applied to the results to measure the size of the differences and for any statistical significance.

Results

The results found that regardless of the form of physical activity or class duration, there was a positive change in the mood of participants. Differences in size of the changes, when compared to the forms of physical activity and gender, were not found.

Conclusions

The improvement in mood of fit and regularly physically active adults is observed regardless what form of physical activity is practiced.
An assessment of athletic identity in blind and able-bodied tandem cyclists
Authors: Tasiemski Tomasz , Wilski Maciej , Mędak Kamila
Published: June 2012

Purpose

The purpose of this study was to determine the athletic identity (AI) of blind and able-bodied tandem cyclists and explore its relationship to selected variables. An additional objective of this study was to analyze the reliability of the seven-item Athletic Identity Measurement Scale (AIMS) for tandem cyclists.

Methods

The participants (N = 50) completed measures of AI, variables characterizing their loss of vision (degree and time of loss) and variables characterizing their sports level (the number of hours of training per week and sports experience).

Results

The AI level of able-bodied tandem captains is significantly higher than the level in visually impaired athletes. Blind tandem cyclists were found to be a fairly homogeneous group according to AI. There were no differences in AI and the degree and time of vision loss, the number of hours of training per week and when a cycling license was received. Psychometric analysis showed that AIMS is a reliable and consistent research tool in the evaluation of AI of tandem cyclists.

Conclusions

The findings suggest that there is a need to increase the involvement of blind cyclists in the sport as well as their responsibility for sports results.
Hydrometeorological parameters and aquatic chemistry of Lake Engure: Trends of changes due to human impact and natural variability
Authors: Kļaviņš Māris , Kokorīte Ilga , Rodinovs Valērijs , Avotniece Zanita , Spriņge Gunta , Briede Agrita
Published: June 2012

Hydrometeorological parameters and aquatic chemistry of Lake Engure: Trends of changes due to human impact and natural variability

Lake Engure, located in Latvia, is the largest shallow coastal lake that developed after retreat of the Littorina Sea. It supports high biodiversity and has national and international importance. Engure is a hardwater lake with abundant macrophyte and charophyte vegetation. The present study determined the impact of the main meteorological indicators related to global warming, and also indicators of climate extremes. The lake water level is regulated by hydrotechnical constructions. In the the warm period (April-October) of the year the lake level tends to increase. However, from a perspective of long-term changes, there was a good relationship between the Western type of Atmospheric Circulation Index and water level in general, and also between NAO index in March and lake water level in April. Regarding water chemical composition, there has been a decrease of phosphorus concentration while ammonium and nitrate concentrations have not changed. Ionic composition of Lake Engure is characterised by dominance of hydrocarbonates, calcium and magnesium ions.
Alien flora in the Lake Engure Nature Park
Authors: Gavrilova Gertrūde , Laiviņš Māris , Priede Agnese , Medene Anda
Published: June 2012

Alien flora in the Lake Engure Nature Park

This paper describes the alien vascular plant flora in the Lake Engure Nature Park, one of the most species-richest and diverse areas in Latvia. The review was based on the floristic inventories conducted in 1983-1989 and a field survey carried out in 2010. In total, 68 alien species (7.6% of the vascular plant flora in the nature park) were recorded, of which four had established in the period between both surveys. 22 species were recognised as adventive species and 46 as escaped species. Most of the alien species area concentrated in coastal villages, around human settlements, roadsides, coastal dunes and along streams discharging in the Lake Engure, thus mostly in transformed habitats. They are absent in most of the natural and semi-natural habitats. In comparison to the overall situation in Latvia, the Lake Engure Nature Park area is relatively little affected by plant invasions, most probably because large areas of natural and semi-natural habitats remain, since high naturalness of vegetation plays a significant role as a natural barrier hindering alien invasions.
Effect of water level and climatic factors on the radial growth of black alder
Authors: Elferts Didzis , Dauškane Iluta , Ūsele Guna , Treimane Agita
Published: June 2012

Effect of water level and climatic factors on the radial growth of black alder

Black alder (Alnus glutinosa (L.) Gaertn.) is a widespread tree species in Europe and the western part of the temperate climate zone. The area of forest in Latvia dominated by this tree species has substantially decreased due to wide-spread forest drainage. To predict future changes due to environmental change, it is extremely important to understand the function of ecosystems with black alder and their dynamics. Tree rings can be used as a proxy of past environmental factors. The aim of the study was to determine the effects of meteorological and hydrological factors on radial growth of black alder at two study sites (Dursupe and Raķupe) in Latvia. The response of black alder trees to the influence of climatic and hydrological factors was found to depend on site conditions, i.e. a climatic effect was observed in conditions when the water level was low. Spatial variation in the strength of the relationship of black alder growth to temperature, precipitation, and river level suggests that alder growth is more susceptible to drought stress on higher river banks, where the water table is deeper. Black alder trees growing on low river banks can potentially be used to reconstruct past water-levels.
Dynamics of emergent macrophytes for 50 years in the coastal Lake Engure, Latvia
Authors: Brižs Jānis
Published: June 2012

Dynamics of emergent macrophytes for 50 years in the coastal Lake Engure, Latvia

Coastal Lake Engure is a Ramsar site — a wetland of great importance due to its biological diversity and unique properties, especially its coverage of macrophytes, shallowness and size. This study assesses the dynamics of emergent macrophytes in the lake based on analysis of historical aerial photographs and digital orthophoto maps. The area of emergent macrophytes was shown to have increased by 781 ha (15 ha/year) in the period 1956 to 2007. The expansion rate differed during this period. Expansion was much faster (31 ha/year) from 1956 to 1972, but declined to 6 ha/year from 1972 to 1994 and increased again to 11 ha/year from 1994 to 2007. The greatest rates of expansion of emergent macrophytes from 1956 to 1972 can be partly explained by ceased grazing and hay harvesting activities. As the area covered by emergent macrophytes changes seasonally, only remote sensing materials acquired during the same season should be compared. The open water territory in 2007 was only 22.9 km2, compared to 30.7 km2 in 1956. Emergent vegetation has been mostly limited to areas where the depth does not exceed 0.5 m. Expansion of emergent vegetation was found to differ in various parts of the lake. The main factors affecting the rates of its development were wave disturbances, hydrological regime and ceased agricultural activities in the lake.
Environmental quality assessment of the drainage basin of Lake Engure using Scots pine as a bioindicator
Authors: Melece Ināra , Karpa Aina , Laiviņš Māris , Melecis Viesturs
Published: June 2012

Environmental quality assessment of the drainage basin of Lake Engure using Scots pine as a bioindicator

Environmental quality assessment of the Lake Engure drainage area, which is the LT(S)ER region of the Latvian National Long-term Ecological Research network (Latvia LTER), was conducted using three bioindication methods based on Scots pinePinus sylvestrisL.: unspecific bioindication by pine needle tip necrosis, ground level ozone assessment by pine needle chlorotic mottling, and chemical analysis of pine bark. Samples were collected from 40 sites of the region in November 2010. Extent of needle tip necroses did not exceed class 4 (maximum possible value 6). The highest value of index of needle damage by ozone was Idam= 1.62 (maximum possible value 6). Multiple regression analysis of variables describing bark chemistry and needle damage in relation to distance from the sea, nearest roads and villages was performed. Pine bark acidity pH(KCl) and concentration of Mg and Fe decreased significantly (βpH(KCl)= -0.672,P< 0.001; βMg= -0.676, P< 0.001;βFe= -0.514, P< 0.001) with distance of sample site from gravel roads. Electric conductivity (EC) of pine bark and the extent of ozone damage of the first year needles Idamsignificantly decreased with distance from the sea(βozone= -0.507, P< 0.01;βEC= -0.453, P< 0.01). PCA of the pine bark chemistry data showed dust pollution from gravel roads to be the main factor responsible for the 33% variation of data. No statistically significant correlations were found between different bioindicator characteristics, except between first and second year ozone damage (ρ = 0.589, P = 0.01).
Tourism policy and management for conservation of biodiversity in the Lake Engure catchment area
Authors: Leitis Ēriks
Published: June 2012

Tourism policy and management for conservation of biodiversity in the Lake Engure catchment area

Tourism services are beginning to offer an increasing array of new niche product including ecotourism in protected nature reserves that contain many rare and protected animal and plant species. Consequently, even ecotourism, which is generally considered as being environmentally friendly, may threaten the maintenance of natural biodiversity. In order to avoid possible risks it is necessary to examine the existing and prospective environmental impact caused by tourism and to analyse relevant policy, with the goal to develop an effective tourism model in which protection of the environment has priority over economic interests. It is important to integrate such a policy into this model, which will serve to reduce social and economic pressures on biodiversity and will promote responsible actions in support of environmentally friendly technologies and approaches. The selected area for this study was the Lake Engure catchment area, which includes a diverse range of ecosystems and developed tourism facilities. The results of this investigation revealed comparatively little tourism activity, which is mostly seasonal and with low environmental impact. The area is attractive for its biodiversity and culture heritage. Further improvement of the tourism infrastructure and information flow will most certainly increase the number of visitors, thus making it necessary to develop sustainable management of tourism resources.
Grain quality traits important in feed barley
Authors: Bleidere Māra , Gaile Zinta
Published: June 2012

Grain quality traits important in feed barley

Spring barley (Hordeum vulgare L.) traditionally has been a major cereal crop for animal feed especially in Northern areas and also in Latvia. It is complicated to define what the ideal feed barley should be, as the requirements widely differ not only for different species, but even for different age groups of the same species of animals. Therefore, the breeding of feed barley has been developing very slowly and building on the basis of agronomic and beer barley quality parameters. Targeted breeding of barley varieties for a definite application purpose of the grain is connected with selection according to different criteria. The present article shows that the feed quality of barley is influenced both by physical grain quality indicators (colour, grain weight and size, hull content, 1000 grain weight, volume weight and grain hardness) and by the chemical composition (carbohydrates, non-starch polysaccharides, amino acids, fibre, protein, fat, minerals and vitamins). On the basis of the information collected, a profile of a high quality feed barley variety for different groups of animals is defined.
Use of DNA markers for cereal line uniformity assessment
Authors: Ruņgis Dainis , Gaile Ilze , Veinberga Ilze , Zute Sanita , Strazdiņa Vija , Bleidere Māra , Kronberga Arta
Published: June 2012

Use of DNA markers for cereal line uniformity assessment

Prior to the registration of a new variety, it is required to undergo Distinctness, Uniformity and Stability (DUS) testing. Preparing a newly developed variety to meet the requirements of DUS testing is a lengthy process, particularly regarding aspects of uniformity and stability. Field testing of a large number of lines is time and resource intensive. In addition, the expression of certain traits may be influenced by environmental conditions. The use of DNA markers may allow rapid assessment of the level of genetic diversity within a particular line or variety, and to remove individuals that are genetically differentiated, thus accelerating the homogenisation of a newly developed variety. In this study, we utilised AFLP and the iPBS marker techniques to assess genetic variation within advanced breeding lines of several cereal species (triticale, wheat, barley). The combined use of molecular and morphological selection over three years of analysis and selection resulted in the reduction of genetic diversity within breeding lines.
Variation of spring barley agronomic traits significant for adaption to climate change in latvian breeding programmes
Authors: Bleidere Māra , Mežaka Ieva , Legzdiņa Linda , Grunte Ilze , Beinaroviča Indra , Rostoks Nils
Published: June 2012

Variation of spring barley agronomic traits significant for adaption to climate change in latvian breeding programmes

Breeding programmes have been recently challenged by climate change. Spring barley (Hordeum vulgare L.) yield, phenological traits (days to heading, length of filling period and days to maturity) and resistance to powdery mildew and net blotch, which are influenced by the rising temperature and precipitation, along with threshability in hulless, were evaluated and their genetic and environmental variability were determined. One hundred and ninety spring barley genotypes were studied, including 129 hulless genotypes and 61 hulled genotypes. The genotypes were grown in the State Stende Cereal Breeding Institute and State Priekuļi Plant Breeding Institute for three seasons during 2007-2009. Broad-sense heritability estimated on the basis of genotypical and phenotypical variances for all traits of hulled barley varied from 31 to 98, and 42 to 98% for hulless barley. For both types of barley the highest heritability was observed for days to heading, filling period and days to maturity. Despite the relatively high estimated heritability for all traits, nevertheless, location, year and interaction of genotype and environment were also been significant for all traits.
Risk assessment in renewable energy production from agriculture biomass in Latvia
Authors: Rivza Baiba , Rivza Sandija , Rivza Peteris
Published: June 2012

Risk assessment in renewable energy production from agriculture biomass in Latvia

The concepts "risk", "crisis", "danger" have become commonly used and recognised in various fields of entrepreneurship, governance, agriculture and environment protection. Risk management and risk evaluation nowadays has not only theoretical, but also practical application. Risk assessment is an important factor for successful and sustainable entrepreneurship of bioenergy production, which has become one of the priorities in the energy sector of Latvia — promotion of the use of renewable energy is included as one of the strategic goals for both European Union (EU) and Latvia. The present research focuses on risk assessment and choice of risk management alternatives in renewable energy production form agriculture biomass, since this type of energy is viewed as a perspective source for renewable energy production in Latvia. This field of energy production in Latvia is rather new and scantily explored, and therefore there are many risk factors that arise in different stages of energy production, starting with planning and building of a bioreactor and ending with production and further use and distribution of energy. A risk assessment module for renewable energy production made using Analytic Network Process (ANP) software is described in the paper.
Psychological consequences of money and money attitudes in dictator game
Authors: Gąsiorowska Agata , Hełka Anna
Published: June 2012

Psychological consequences of money and money attitudes in dictator game

According to the research conducted by Vohs, Mead, and Goode (2006, 2008), reminders of money cause people to behave self-sufficiently, and especially to reveal a reduced tendency to charitable behaviour. In this study, we wanted to establish if this tendency would be present in the dictator game, and if so, whether money activation would just change behaviour, or whether it would also change people's evaluation of their own decisions. We assumed that people who revealed symbolic and instrumental money attitudes would react differently to money activation. As expected, money priming caused smaller money transfers compared to the control condition, and this effect was significant among those with symbolic attitudes toward money. Moreover, participants who transferred at least half of the sum after money activation declared stronger negative emotions and lower satisfaction with the decision than those who made similar transfers in the control condition.
The Effect of Major Alloying Elements on the Size of Secondary Dendrite Arm Spacing in the As-Cast Al-Si-Cu Alloys
Authors: Djurdjevič M. , Grzinčič M.
Published: June 2012

The Effect of Major Alloying Elements on the Size of Secondary Dendrite Arm Spacing in the As-Cast Al-Si-Cu Alloys

A comprehensive understanding of melt quality is of paramount importance for the control and prediction of actual casting characteristics. Among many phenomenon that occur during the solidification of castings, there are four that control structure and consequently mechanical properties: chemical composition, liquid metal treatment, cooling rate and temperature gradient. The cooling rate and alloy composition are most important among them. This paper investigates the effect of the major alloying elements (silicon and copper) of Al-Si-Cu alloys on the size of secondary dendrite arm spacing. It has been shown that both alloying elements have reasonable influence on the refinement of this solidification parameter.
Influence of Compound Deoxidation of Steel with Al, Zr, Rare Earth Metals, and Ti on Properties of Heavy Castings
Authors: Senberger J. , Cech J. , Zadera A.
Published: June 2012

Influence of Compound Deoxidation of Steel with Al, Zr, Rare Earth Metals, and Ti on Properties of Heavy Castings

Heavy steel castings deoxidized with aluminium are sometimes brittle intercrystalline failed during their service along primary grain boundaries what is initiated by aluminium nitrides and so called conchoidal fractures are formed. The tendency to forming the conchoidal fractures depends in particular on cooling rate (the casting modulus), aluminium and nitrogen contents in steel. During deoxidation, when manufacturing heavy castings, the elements with high affinity to nitrogen, zirconium or titanium, are added to steel that would decrease nitrogen activity by the bond on stable nitrides. The formation of stable nitrides should reduce the tendency of steel to the formation of conchoidal fractures. Deoxidation was thermodynamically analyzed at presence of the mentioned elements. For particular conditions a probable course of deoxidation was estimated at test castings. The deoxidation course was checked by microanalysis of deoxidation products (inclusions). For service and experimental castings the anticipated composition of inclusions was compared. It has been proved that in heavy castings with high aluminium contents in steel under studied conditions neither the addition of zirconium nor of titanium nor of rare earth metals will prevent the formation of conchoidal fractures.
The Mechanism of the Surface Alloy Layer Creation for Cast Steel
Authors: Walasek A. , Szajnar J.
Published: June 2012

The Mechanism of the Surface Alloy Layer Creation for Cast Steel

The paper presents a detailed description of the process of creation of a surface alloy layer (using high-carbon ferrochromium) on the cast steel casting. The mechanism of the surface alloy layer is based on the known theories [5,6]. The proposed course of formation of the layers has been extended to decarburization stage of steel. The research included proving the presence of carbon-lean zone. The experiment included the analysis of the distribution of elements and microhardness measurement.
Effectiveness of chosen robust estimation methods compared to the level of network reliability
Authors: Kwaśniak Mieczysław
Published: June 2012

Effectiveness of chosen robust estimation methods compared to the level of network reliability

The work presents the results of studies on dependence of effectiveness of chosen robust estimation methods from the internal reliability level of a geodetic network. The studies use computer-simulated observation systems, so it was possible to analyse many variants differing from each other in a planned way. Four methods of robust estimation have been chosen for the studies, differing substantially in the approach to weight modifications. For comparative reasons, the effectiveness studies have also been conducted for the very popular method in surveying practice, of gross error detection basing on LS estimation results, the so called iterative data snooping. The studies show that there is a relation between the level of network internal reliability and the effectiveness of robust estimation methods. In most cases, in which the observation contaminated by a gross error was characterized by a low index of internal reliability, the robust estimation led to results being essentially far from expectations.
Extracorporeal Shock-Wave Therapy for Supraspinatus Calcifying Tendinitis: A Randomized Clinical Trial Comparing Two Different Energy Levels
Authors: Ioppolo Francesco , Tattoli Maria , Di Sante Luca , Attanasi Carmine , Venditto Teresa , Servidio Marila , Cacchio Angelo , Santilli Valter
Published: June 2012

Background

Extracorporeal shock-wave therapy (ESWT) represents a valid intervention in the treatment of people with supraspinatus calcifying tendinitis (SCT), but there is limited evidence for the useful range of ESWT doses.

Objective

The aim of this study was to compare 2 different ranges of energy flux density in treatment of SCT with ESWT.

Design

This study was designed as a single-blind randomized clinical trial.

Setting

This study was performed in a university hospital.

Patients

Forty-six patients with SCT were randomly assigned to 2 groups that received different therapeutic energy doses of ESWT: (1) group A received ESWT at an energy level of 0.20 mJ/mm2, and (2) group B received ESWT at an energy level of 0.10 mJ/mm2.

Intervention

The treatment protocol consisted of 4 sessions performed once a week.

Measurements

The change in mean Constant Murley Scale (CMS) scores at 3 and 6 months was the primary endpoint. The change in the mean visual analog scale (VAS) scores from baseline to 3 and 6 months after the intervention and radiographic change in size of calcium deposits were evaluated as secondary endpoints. At 12 months, pain relief was assessed using a numeric rating scale.

Results

Significant clinical improvement based on mean CMS scores was observed after 6 months in group A (X̅=79.43, SD=10.33) compared with group B (X̅=57.91, SD=6.53). Likewise, after 6 months, a significant decrease in VAS scores was found in group A (X̅=2.09, SD=1.54) compared with group B (X̅=5.36, SD=0.78). Calcific deposits disappeared in the same percentage of patients in both groups.

Limitations

The small sample size and lack of a control group were limitations of the study.

Conclusions

In ESWT for SCT, an energy level of 0.20 mJ/mm2 appears to be more effective than an energy level of 0.10 mJ/mm2 in pain relief and functional improvement.
Back Pain Beliefs Are Related to the Impact of Low Back Pain in 17-Year-Olds
Authors: Smith Anne J. , O'Sullivan Peter B. , Beales Darren , Straker Leon
Published: June 2012

Background

Disability in adults with low back pain (LBP) is associated with negative back pain beliefs (BPBs). Adult BPBs can be positively influenced with education, resulting in reduced LBP disability. By late adolescence, the prevalence of LBP reaches adult levels. The relationship among LBP experience, LBP impact, and BPBs has not been investigated in late adolescence.

Objective

The aim of this study was to document unknown relationships among LBP experience, LBP impact, and BPBs in 17-year-olds.

Design

A cross-sectional study design was used.

Methods

Adolescents (n=1,126) in the Raine Study provided full information on LBP, LBP impact (sought professional advice or treatment, taken medication, missed school or work, interfered with normal activities, interfered with physical activities), BPBs, and a number of covariates.

Results

Back pain beliefs were more positive in participants with experience of LBP (X̄=30.2, SD=5.6) than in those without experience of LBP (X̄=28.5, SD=5.1). Individuals with LBP without activity modification impacts had more positive BPBs than those with activity modification impacts, even after adjustment for mental well-being and sex. The adjusted difference in BPBs between participants with experience of LBP but no activity modification impacts and those reporting all 3 activity modification impacts was 2.9 points (95% confidence interval=1.7 to 4.2). Participants with no activity modification impacts had more positive BPBs than those with no experience of LBP (adjusted difference=2.2 points, 95% confidence interval=1.4 to 2.9). More positive BPBs also were associated with female sex, lower body mass index, higher family income, better 36-Item Short-Form Health Survey (SF-36) Mental Health scale scores, and more positive primary caregiver beliefs.

Limitations

Cause and effect cannot be ascertained with the cross-sectional design.

Conclusion

Differences in BPBs are associated with different levels of LBP impact at 17 years of age. This finding provides a potential target for intervention early during the life course.
Discussion of defect analysis of a Ti-6Al-4V alloy forging ring
Authors: Huang Zhanghong , Qu Henglei , Ye Hongchuan , Deng Chao , Wu Hua , Ma Hongzheng , Yang Jianchao
Published: June 2012

An open crack was found in a Ti-6Al-4V alloy forging ring. Optical observation, scanning electron microscopy analysis, energy-dispersive X-ray spectroscopy, hardness test and X-ray photoelectron spectroscopy were applied to find out the reason. It was found there was an obvious transition zone from the edge of the crack to the matrix on one side of the crack, where the shape and size of the microstructure changed from big block to elongated wattle. In addition, the microstructure inside the crack appeared non-compact and porous. Microhardness tests showed that the hardness of the area near the crack was remarkably higher than that of matrix. The results of energy-dispersive X-ray spectroscopy showed that the content of Al and V was much smaller near the crack compared to the matrix. The surface of the crack is basically composed of Ti, Al and V, and no other elements were found in the precision range. X-ray photoelectron spectroscopy results showed that the blocky α-phase area near the crack contained oxygen, carbon and nitrogen. However, no carbon and nitrogen were found in the matrix and the oxygen content was lower.
Rheo-chemistry in Reactive Processing of Polyolefin
Authors: Yu W. , Liu J. , Zhou C.
Published: June 2012

A brief review of reactive processing of polyolefins, which are the most widely used polymers today, is given in this paper from the role of flow field in processing and the characterization of the modified chain topologies. The materials are mainly focused on polyethylene (PE), polypropylene (PP) and polyolefin elastomer (POE) here. Aspects of reactions, coupling/crosslinking and scission are discussed both in terms of the mechanism and kinetics under different flow conditions.
Visualization Analysis of a Multilayer Foam Development Process in Microcellular Injection Molding
Authors: Yamada T. , Murata Y. , Yokoi H.
Published: June 2012

In this study, cross-sectional analyses were performed on microcellular injection-molded high-impact polystyrene products. The results confirm that the following five types of layers were formed: Skin layers I (the silver streak layer) and II (a nonfoamed layer), Core layers I (cell diameter, d > 150 μm), II (d < 50 μm), and III (d > 100 μm). As the maximum in-mold pressure (Pmax) was increased from 5 to 30 MPa, the thickness of Skin layer II remained nearly constant. However, the foam types in the core layers changed from I and II to II and III or III only, resulting in an increase in cell diameter and a decrease in cell density. The process of cellular structure formation was observed using a glass-inserted mold, which revealed that this process consists of a flow (with a burst of cells at the melt front and the subsequent flow of the melt containing the cells), an end of the filling (involving elastic compression or the dissolution and disappearance of cells formed in the flow stage), and a cooling (new cell generation and growth and cooling solidification). Based on these cross-sectional observations, in concert with melt-pressure measurements and visualizations, we developed a model describing the formation process of Skin layer II and the core layers including a new concept that considers the melt pressure inside the cavity. The following layers are incorporated into the model: Skin layer II: A nonfoamed layer is formed in the area of the melt front where gases diffuse out from within the melt during the filling stage, and this nonfoamed layer moves to from melt front to the surface of the product due to fountain flow. Core layers I and II: A multilayer is formed containing a distribution of cells preserved from the flow stage due to the low compression forces, Core layer III: cells are dissolved in the melt due to strong compression forces at the end of the filling stage and then reform and grow in the cooling stage.