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Water-in-oil droplet microfluidics promises capacity for high-throughput single-cell antimicrobial susceptibility assays and investigation of drug resistance mechanisms. Every droplet must serve as an isolated environment with a controlled antibiotic concentration in such assays. While technologies for generation, incubation, screening, and sorting droplets mature, predictable retention of active molecules inside droplets remains a major outstanding challenge. Here, we analyzed 36 descriptors of the antibiotic molecules against experimental results on the cross-talk of antibiotics in droplets. We show that partition coefficient and fractional polar surface area are the key physicochemical properties that predict antibiotic retention. We verified the prediction by monitoring growth inhibition by antibiotic-loaded neighboring droplets. Our experiments also demonstrate that transfer of antibiotics between droplets is concentration- and distance-dependent. Our findings immediately apply to designing droplet antibiotic assays and give deeper insight into the retention of small molecules in water-in-oil emulsions.

The quality of fruit as a source of bioactive ingredients is related to the genetic characteristics of plants, but it can also be modified by growing conditions. Therefore, long-term research can be extremely valuable in evaluating various crop plants, especially novel ones. The aim of the research was to test four popular European kiwiberry (

The quality of fruit as a source of bioactive ingredients is related to the genetic characteristics of plants, but it can also be modified by growing conditions. Therefore, long-term research can be extremely valuable in evaluating various crop plants, especially novel ones. The aim of the research was to test four popular European kiwiberry (Actinidia arguta) cultivars (‘Geneva’, ‘Bingo’, ‘Weiki’, ‘Anna’) in terms of selected morphological features, yield, and chemical composition as well as their variability over 3 years. It can be concluded that the studied genotypes were very diverse in terms of the biochemical compounds’ concentration in individual seasons. The cultivars ‘Anna’ and ‘Weiki’ were the most similar ones with respect to each other in terms of morphology and chemical composition. The cultivars ‘Bingo’ and ‘Geneva’ were definitely different. ‘Bingo’ was characterized by the largest and most uniform fruits in each season and had the highest concentration of vitamin C but the lowest carotenoid concentration. In turn, ‘Geneva’ produced the smallest fruit in each season with the highest concentration of polyphenols and a high concentration of carotenoids and displayed the highest antioxidant capacity regardless of the determination method. The research was performed with the application of computer-supported statistical analysis.

Influence of moisture on maturation rate of the airborne Venturia inaequalis (Cooke) Wint. ascospores was numerically examined using field data collected from spore traps in Skierniewice, Poland, during 2005–2008 and 2010–2014. In order to avoid a bias resulting from different abundance of airborne ascospores in different seasons, the cumulative proportions of mature ascospores observed in the season were analyzed. The maturation rate was expressed with the probit of cumulative proportion which linearized its sigmoidal shape and made the effect of the weather during the entire season of the same importance. The significant, positive association between the probit slope and the moisture indicators related to precipitation, leaf wetness, and high relative humidity were observed. Additionally, the significant, negative relationships with the average and maximal air temperature were found. The results suggested that rain should be treated as the major factor driving the ascospore development and leaf wetness as the second factor. In conclusion, the main sources of moisture should be taken into account in statistical models of ascospore development, but it seems reasonable to take into account different strength of their association with the development rate.

Models of maturation rate of the airborne Venturia inaequalis (Cooke) Wint. ascospores were compared using field data collected from spore traps in Skierniewice, Poland, during 2005–2008 and 2010–2014. Two sets of models describing ascospores maturation rate as a function of cumulative temperature were compared. The first set consisted of the “Stensvand” model with degrees summed during and 147 h after the rainfall, and the “Only” type models accumulating temperature only during hours with observed high moisture level indicated by rain, leaf wetness or high humidity. The second set consisted of more complex “All” type models proposed in the study, with degrees summed each hour, but differently weighted for periods with various sources of moisture such as rain, leaf wetness (LW) and relative air humidity (RH). The “All” type models proved to be superior over the “Only” type models. The “All Rain + LW + RH,” “All Rain + LW,” “All LW” and the “Stensvand” models gave the best match with the data. The final and most important result of the study is such that all of the examined models had high and unsatisfactory range of models’ uncertainty for the data from central Poland. Therefore, further improvements in modeling of ascospore maturation rate are necessary. Low accuracy of the models limits their practical application at the current stage of development.

The aim of the study was to examine the possible factors that might contribute to consumer acceptance of food innovations. Particular attention was paid to 3 main factors: (a) relationship between socio-demographic determinants and level of consumer innovation, (b) evaluation of consumer innovation acceptance, particularly toward animal-derived food products, and (c) consumer preferences for health-promoting food innovation over time. Studies were conducted using quantitative research methods in 2004 and 2011. An organic method of production, least important in 2004, was top rated in 2011, and ease of preparation dropped to the bottom of the list in 2011, whereas food origin, low fat, and sugar content were ranked in the first group of the considered factors in 2011. Since 2004, consumers have become used to products with various innovations. The new generation of Poles is relatively more open to new food products, due to the wide range of food products available on the free market. Furthermore, the group of well-educated consumers with a higher level of income has increased in size, and this includes people interested in knowledge of a product's nutritional value and its health impact. Our study extends existing research in the area of understanding consumer expectations toward food innovations. The results not only contribute to the field of consumer behavior but also have practical potential for food market applications, especially for companies operating on or planning to enter the Polish food market, and which could be used for developing communication strategies.

Sustainable urban forests require tree acceptance and support. Two groups of respondents, professionals (working in urban green areas) and individuals (with no professional connection with trees) revealed their attitudes towards trees by assessing statements in a survey questionnaire. Similar general attitude from professionals and nonprofessionals towards the examined benefits and harms related to urban trees was observed. Tree benefits were perceived as much more important than the annoyance they might cause. However, 6% of nonprofessionals found only negative aspects in trees, proving to be arboriphobes. No arboriphobes and no &ldquo, Tree sceptics&rdquo, were among the professionals. Around 40% of the respondents in the two groups found the number of trees in the surrounding areas too low. The nuisance caused by trees was seen as more disturbing by younger and lower-educated professionals. Women tended to assess trees as more attractive and as having a stronger influence on socioeconomic contributions than men. Men dominated the &ldquo, Tree indifferent&rdquo, group. The attractiveness of trees and their impact on socioeconomic contributions were related to the place of residence and the level of education among the nonprofessionals. The level of education of the nonprofessionals was also connected to being clustered into one of the four abovementioned groups of respondents. A majority of medium and big city dwellers as well as a minority of villagers were in the &ldquo, Tree liking&rdquo, cluster.

The linden tree (Tilia spp.) is a popular tree for landscaping and urban environments in central and northwest European countries, and it is one of the most popular in cities in Poland. Ectomycorrhizal fungi form a symbiosis with many urban tree species and protect the host plant from heavy metals and against salinity. The aim of this study was to characterise the ECM fungal community of urban linden trees along the tree damage gradient. The study was performed on two sites located in the centre of the city of Gdańsk, in northern Poland. The vitality assessment of urban linden trees was made according to Roloff’s classification. Tree damage classes were related to soil characteristics using principal component analysis. The five ectomycorrhizal fungal species were shared among all four tree damage classes, and Cenococcum geophilum was found to be the most abundant and frequent ectomycorrhizal fungal species in each class. Soil samples collected in the vicinity of trees belonging to the R0 class had significantly lower pH Na, Cl and Pb content than other soils. Our knowledge of ectomycorrhizal communities in urban areas is still limited, and these findings provide new insights into ectomycorrhizal distribution patterns in urban areas.

Sustainable urban forests require tree acceptance and support. Two groups of respondents: professionals working in urban green areas and individuals with no professional connection with trees revealed their attitudes towards trees by assessing statements in a survey questionnaire. Tree benefits were perceived as much more important than the annoyance. However, 6% of the non-professionals found only negative aspects of trees, proving to be arboriphobes. No arboriphobes and no “tree sceptics” were among the professionals. Around 40% of the respondents in the two groups found the number of trees in the surrounding areas too low. The nuisance caused by trees was seen as more disturbing by younger and lower educated professionals. Women tended to assess trees as more attractive and as having a stronger influence on social relations than men. Men dominated the “tree indifferent” group. The attractiveness of trees and their impact on social relations were related to the place of residence and the level of education among the non-professionals. The level of education of the non-professionals was also connected to being clustered into one of the four abovementioned groups of respondents. A majority of medium and big city dwellers as well as a minority of villagers were in the “tree liking” cluster.

The article presents the vision of the development of countries and societies as seen in threeworks from the 1990s: Francis Fukuyama’s End of History, Samuel Huntington’s The Clash ofCivilisations and Benjamin Barber’s Jihad vs McWorld. The author compares these visions to the contemporary world, together with their utopian and dystopian aspects, wondering whichof them more accurately predicted the directions of its development. Treating these works asan entry point, he considers the alternatives of the dominating liberal democracy, analysesthe features of the more and more popular neomedievalism and the flaws and advantages ofdirect democracy. Talking about direct democracy, he describes the only functioning exampleof such political system in Switzerland. Describing its details and specification, he wonders ifthe system analogous to the Swiss one could be useful somewhere else. By referring to thisproblem in the context of technological advancement, he considers the issue of developingdirect democracy with the use of electronic media. In the end, the again refers to the worksby Barber, Fukuyama and Huntington, expressing his regret for the lack of other, equally boldvisions of the world and political systems development in contemporary times.Key words: political system, liberalism, direct democracy, neomedievalism

The yeast microbiota occurring on different varieties of grapes grown in cool-climate is not completely researched. Therefore, its identification is important to research. On the other hand, yeasts occurring in these fruits can be potentially used as starter cultures to obtain particularly demanded features in the production of wine. In addition, rapid methods for yeast identification allow to eliminate the contamination with pathogenic yeasts, which could cause the loss of wine production. The aim of the study was to isolate and identify the yeasts occurring on the surface of the different varieties of white and red grapes, grown in cool-climate of Poland. Also, the aim was to compare the qualitative and quantitative composition of yeasts on the tested grapes. The 84 cultures of yeasts were isolated, that were initially macroscopic and microscopic analyzed and the purity of cultures was rated on the WL medium. Identification of yeasts by PCR-RAPD was carried using the M13 primer. In the PCR-RFLP method ITS1 and ITS4 primers, as well as restriction enzymes HhaI, HinfI, HaeIII, were used. Preliminary identification of yeasts by standard methods produced results very different from the results obtained by molecular methods. Among the isolated microorganisms yeasts were dominating, but bacteria and molds were also present. Using the PCR-RAPD method most strains of yeasts were identified. Yeast microflora of different varieties of white and red grapes was very similar as the same species of yeasts were identified. Yeasts of the genus Saccharomyces were present in all varieties of grapes. The Rhodotorula mucilaginosa, Saccharomyces cerevisiae, Metschnikowia pulcherrima, Rhodotorula minuta, Pichia kluyveri, Hanseniaspora uvarum and Rhodotorula mucilaginosa were identified by PCR-RAPD. 4 of the 33 tested strains of yeasts were identified by PCR-RFLP. By PCR-RAPD only Hanseniaspora uvarum was identified. The quantity and quality of microorganisms living on the surface of grape fruits is very important for the process of winemaking. Yeasts influence the course of alcoholic fermentation, the flavor, aroma, and thus the quality of the produced wine. To a large extent their presence depends on the condition of the surface of the fruit. Many researchers reported significant differences between yeast microflora in grapes of Mediterranean and cool-climate vineyards. As they are expected to affect the final wine properties precise researching of the microflora of cool-climate grapes may lead to the isolation of new species of yeasts and thus the wines with unique characteristics can be obtained.

This case report presents the diagnostic and treatment procedures of stone removal from the kidney of a 67-year-old donor, the transplantation of the kidney to a 65-year-old recipient, and the postoperative course until the end of hospitalization. Computed tomography performed before collecting the organ showed a staghorn stone in the renal pelvis and lower calyces in the right donor kidney. The stones were removed ex-vivo using a rigid ureteroscope and a holmium laser prior to transplantation. Then the organ was transplanted to the left iliac fossa of a 65-year-old man with end-stage renal failure. The authors think there is a possibility of increasing the kidney pool, by using organs containing large calculi. In such cases stones should be removed before the operation and the patient should be monitored regularly, especially in the first months after the transplant.

A simple method for reducing the uncertainty intervals of models describing the maturation of Venturia inaequalis (Cooke) Wint ascospores is described. The number of trapped ascospores related to the current accumulated degree days of the season, and the confidence interval predicted with the historical ascospore release datasets, were used to re-calculate the confidence interval for the ascospore proportion for the rest of the season. The historical uncertainty in ascospore proportion was described with logistic functions fitted to upper and lower confidence limits of the mean of fitted values for several years of ascospore release data. The re-calculated confidence interval was derived by the determination of the total number of ascospores that would be trapped during the season, if the current day cumulative release were at either the upper or lower confidence limit of the historical data. The method was examined by applying three models of ascospore maturation and using ascospore trap and weat...

A total of 128 Polish professionals (active and future designers, construction employees, and public officials) were questioned about their awareness and experience of tree protection practice in a survey conducted during tree diagnostic training sessions. According to the experienced professionals, trees were not protected at all in a significant proportion of projects. In the experience of nearly two thirds of professionals, trees on construction sites were protected in less than 60% of the projects in which they were involved. Half of respondents estimated that in over 60% of the projects where any protection was applied it was insufficient. Constraints related to the shape of the construction site, lack of funds, and insufficient knowledge were the main factors leading to the lack of tree protection. The main reason for any tree protection being in place was the legal regulations. Although respondents did not perceive the regulations as a source of knowledge, they believed that effective enforcement of penalties could be one crucial way to protect trees on construction sites, alongside specialist support. According to the results of the survey, awareness of the value of trees did not lead to tree protection. Respondents rated highly their knowledge about the influence of soil properties on tree survival and development, the growth and reaction of trees to damage, and tree protection in construction projects, but nevertheless admitted that they lacked knowledge of the technical issues of tree protection.

The article presents the results of a study investigating the links between emotion regulation and identity. The aim of this study was to explore the relationship between the two variables. On the basis of neo-eriksonian theories, an attempt to specify the role of emotion regulation in the process of identity formation was made. The study involved 849 people (544 women, 304 men) aged 14-25. The participants attended six types of schools: lower secondary school, basic vocational school, technical upper secondary school, general upper secondary school, post-secondary school, and university. The research was conducted with the use of two questionnaires: Difficulties in Emotion Regulation Scale (DERS) and Dimensions of Identity Development Scale (DIDS). The analysis of the results points to a partial confirmation of the assumed hypotheses about the differences between people with different identity statuses in respect of the six investigated dimensions of emotion regulation. Also, the hypotheses about the links between the dimensions of emotion regulation and dimensions of identity in the subgroups with different identity statuses were partially confirmed.

The article presents the results of research on relationships between types of social participation and emotion regulation. In the study, Gratz’ and Roemer’s (2004) perspective on emotion regulation and Reinders’ and Butz’s (2001) concept of types of social participation were applied. Participants were 1151 students from three types of vocational schools: basic vocational school (n=266), technical upper secondary school (n=644), and specialized upper secondary school (n=241). The results of studies conducted with the use of Difficulties in Emotion Regulation Scale (DERS) and Social Participation Questionnaire (SPQ-S 1) indicate that there are small, however, significant, differences in the levels of social participation dimensions and the frequency of particular types of social participation between students from the three investigated types of vocational schools. The level of transitive orientation turned out to be higher among students from the basic vocational schools than among students from the specialized upper secondary schools and the technical upper secondary schools. In each educational group, the level of transitive orientation was significantly higher than the level of moratorium orientation. The hypothesis about the relationship between dimensions of emotion regulation and types of social participation, particularly with respect to the dimension of “lack of emotional awareness”, was confirmed. The most effective style in terms of emotion regulation turned out to be the assimilation type. The highest level of emotion dysregulation proved to be connected with the segregation type.

Biodiversity analysis of metagenomic and metatranscriptomic data acquired from next-generation sequencing (NGS) requires following multiple analytic steps, often independent from each other with exception of passing output files of previous step as input for the following. If parameterization of steps following one after another is independent from one another, they may be pipelined. There are three most popular pipelines used for NGS analyses: QIIME, mothur and MetAMOS. In this work we describe our extensions to the latter. One is supplementing MetAMOS’ default modes with taxonomic and metabolic biodiversity using metagenomics and metatranscriptomics data and the other provides a web-based interface to run predefined analyses that is easy to integrate with laboratory information management systems.

Artykuł prezentuje wyniki badania dotyczącego związku funkcji wykonawczych i powodzenia szkolnego. W badaniu udział wzięło 46 dzieci w wieku 7 i 8 lat, uczniów pierwszej klasy szkoły podstawowej. W zakresie funkcji wykonawczych dokonano pomiaru dwóch ich przejawów: elastyczności poznawczej i zdolności tworzenia pojęć. Do ich pomiaru użyto dwóch narzędzi, z których jedno zostało stworzone na podstawie testu sortowania kart Wisconsin. Dla drugiego pierwowzorem był dwuwymiarowy test sortowania kart. W celu zbadania powodzenia szkolnego dokonano jego pomiaru z trzech różnych perspektyw: uczniów, nauczycieli i rodziców. Powodzenie szkolne z perspektywy uczniów i rodziców badano narzędziami stworzonymi na podstawie ankiety powodzenia szkolnego autorstwa Anny Żurawskiej (wywiad z uczniami, kwestionariusz dla rodziców);, trzecim wskaźnikiem powodzenia były oceny szkolne. Wyniki wskazują na istotne znaczenie funkcji wykonawczych w zakresie elastyczności poznawczej dla powodzenia szkolnego (część z uzyskanych wyników osiąga poziom istotności statystycznej). Natomiast w zakresie drugiego z przejawów funkcji wykonawczych, czyli zdolności tworzenia pojęć, związek z powodzeniem szkolnym zaobserwowano jedynie w przypadku pomiaru dokonywanego wśród uczniów.

Hardy kiwifruit, Actinidia arguta (Siebold et. Zucc) Planch ex Miq. and A. purpurea Rehd. are species with healthy fruit and high frost resistance. Despite being still exotic they start to be grown commercially, therefore they may become an important supplement to the current fruit production in regions with colder climate such as north European countries. The main goal of the study was to assess the genotypic variability of physicochemical and sensory characteristics of A. arguta fruit at the eating ripeness stage. Seven A. arguta genotypes and two hybrids (A. arguta × A. purpurea) including four selected at Warsaw University of Life Sciences, Poland, were evaluated via physicochemical measurements and via quantitative descriptive analysis by a trained sensory panel. The study consisted of two-year evaluation. The study showed high diversity of postharvest physicochemical characteristics of the examined hardy kiwifruit: firmness, soluble solid content, titratable acidity as well as mass and shape. This fruit diversity is significantly increased by the A. arguta and A. purpurea hybrids which are responsible for large part of the colour differences among the genotypes, revealing high potential of cross-breeding of these species. On the other hand, the overall sensory characteristics of the examined genotypes are similar. In general, ripe hardy kiwifruit are characterised with soft, sour and averagely astringent skin with additional irritating note. The taste of the soft, jelly-like pulp is dominated by fruity and sweet tastes with low admixture of irritating, vinous, astringent and sour tastes.

The growth of average spring barley plants of Rasbet and Rastik cultivars is modelled using the canonical approach, based on power-law relations. It is one of the first applications of canonical modelling for plants and the very first for cereals. It uses a much smaller amount of experimental data and physiological knowledge of spring barley than is required in other more advanced approaches. The plant organs (the leaves, stem, ear and grain) are represented as compartments connected by fluxes of dry matter. The compartment variables and fluxes form sets of ordinary differential equations with the parameters constrained by their fits to the experimental data. Four models are described. Two have already been proposed in the literature, and the other two are derived for the purpose of spring barley growth modelling. The models include the phenomena of the accumulation of biomass before anthesis and its redistribution during the grain-filling period. Unlike most modelling approaches, we solely use data from a field experiment that was dedicated to the statistical evaluation of the dependence of spring barley crops on various agronomic conditions. We obtained a very good description of the data with all of the models presented, though only the two dedicated to modelling spring barley have correct biological interpretations. The ranges of the contributions of the spring barley organs to the overall photosynthesis of the barley plants are also estimated. We conclude that canonical modelling is a promising tool for the relatively simple modelling of the growth of cereals and can be applied in the more general crop growth models.

Epipactis helleborine (L.) Crantz (Orchidaceae, Neottieae) can spread by sexual or vegetative propagation. The choice of strategy likely depends on the environmental conditions. The rhizome is the organ of vegetative reproduction; hence, it is crucial to understand its development. Unfortunately, it is hardly possible to investigate rhizome morphology directly, since E. helleborine is a protected species in most European countries. The goal of our investigation was to infer the growth patterns of underground parts of an orchid population from long-term annual observations of its aboveground shoots. We implemented the Minimum Spanning Tree method to determine a likely set of underground connections between shoots and to simulate the annual growth of new rhizomes. Furthermore, we modelled the spatial distribution of shoots with a density kernel estimator to compare the density gradients with the direction of growth of the rhizomes. Observed shoot numbers fluctuated between 72 and 183 from year to year. Our results suggest that (1) vegetative reproduction prevails in the studied population, (2) the population consists of about a dozen clones with a diameter of up to 6 m, (3) rhizomes produce up to five new shoots at one branch end per year, (4) rhizomes develop in the direction of decreasing population density, and (5) nodes of rhizomes may produce new offshoots after up to 7 years of dormancy.

BACKGROUND: One of the problems in marketing fruit is to increase the share of fruits produced in sustainable agriculture to meet the expectation of ecology-oriented consumers. Acceptability of such fruits by the consumers is of paramount importance. The objective of this study was to explore the acceptability of three scab-resistant apple cultivars as compared with three popular conventional cultivars by Polish consumers of various age groups (adults, youngsters and children). Acceptability was tested on apples harvested in two consecutive years (2004 and 2005) after 2 months cold storage. Apple samples were chosen among 22 conventional and scab-resistant cultivars for their distinctive differences in sensory profiles. Consumers evaluated separately the degree of external (appearance) and internal (flavour and texture) liking of an apple using a 9-point hedonic scale (children used a 5-point scale) and completed a questionnaire detailing socio-demographic and apple-concerning behavioural questions. RESULTS: The results based on internal liking data have shown that in all age groups, consumers were similarly segmented into three clusters: cluster 1, which liked all cultivars a great deal and equally; cluster 2, which preferred firm, juicy and rather acidic fruits; and cluster 3, which liked sweeter apples with intensive ripe apple flavour and moderate firmness. CONCLUSION: It is concluded that scab-resistant cultivars with the above sensory characteristics might be accepted by quite a large segment of consumers, in each of the age groups tested. Copyright © 2009 Society of Chemical Industry

When a finite population is to be stratified, one of constraints in stratification is that sample sizes from strata may not be greater than the corresponding stratum sizes and may not be smaller than two. There are several ways of treating this allocation constraint, each providing an alternative approach to stratification. In this article, it is shown that a choice of the approach has a bearing on stratification efficiency. Unfortunately, no particular approach out of the four compared is shown to be the most efficient for each population studied. In addition, the approaches are applied to stratify a real population.

High energy photon colliders (γγ,γe) are based on e-e-linear colliders where high energy photons are produced using Compton scattering of laser light on high energy electrons just before the interaction point. This paper is a part of the Technical Design Report of the linear collider TESLA.1Physics program, possible parameters and some technical aspects of the photon collider at TESLA are discussed.

New, radiatively generated, next-to-leading (NLO) quark $(u,d,s,c,b)$ and gluon densities in a real, unpolarized photon are presented. We perform three global fits, based on the NLO Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations for ${Q}^{2}g1\text{ }\text{ }{\mathrm{G}\mathrm{e}\mathrm{V}}^{2}$, to all the available structure-function ${F}_{2}^{\ensuremath{\gamma}}(x,{Q}^{2})$ data. As in our previous LO analysis we utilize two theoretical approaches. Two models, denoted as ${\mathrm{F}\mathrm{F}\mathrm{N}\mathrm{S}}_{\mathrm{C}\mathrm{J}\mathrm{K}}1$ and ${\mathrm{F}\mathrm{F}\mathrm{N}\mathrm{S}}_{\mathrm{C}\mathrm{J}\mathrm{K}}2$ NLO, adopt the so-called fixed flavor-number scheme for calculation of the heavy-quark contributions to ${F}_{2}^{\ensuremath{\gamma}}(x,{Q}^{2})$; the Cornet-Jankowski-Krawczyk NLO model applies the $\mathrm{A}\mathrm{C}\mathrm{O}\mathrm{T}(\ensuremath{\chi})$ scheme. We examine the results of our fits by a comparison with the LEP data for the ${Q}^{2}$ dependence of the ${F}_{2}^{\ensuremath{\gamma}}$, averaged over various $x$ regions, and the ${F}_{2,c}^{\ensuremath{\gamma}}$. Grid parametrizations of the parton densities for all fits are provided.

A new analysis of the radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, improved in respect to our paper [1], is presented. We perform four new global fits to the experimental data for F2^gamma, two using a standard FFNS approach and two based on ACOT(chi) scheme [2], leading to the FFNS(CJK) and CJK models. We also present the analysis of the uncertainties of the new CJK 2 parton distributions due to the experimental errors, the very first such analysis performed for the photon. This analysis is based on the Hessian method, for a comparison for chosen cross-sections we use also the Lagrange method., Comment: Prepared for Photon 2003: International Conference on the Structure and Interactions of the Photon (Including the 15th International Workshop on Photon-Photon Collisions), Frascati (Italy), 7-11 April 2003; 10 pages, Latex using espcrc2 style, 1 tex and 5 postscript figures; FORTRAN programs available at http://www.fuw.edu.pl/~pjank/param.html

New, radiatively generated, LO quark (u,d,s,c,b) and gluon densities in a real, unpolarized photon are presented. We perform a global 3-parameter fit, based on LO DGLAP evolution equations, to all available data for the structure function F2^gamma(x,Q^2). We adopt a new theoretical approach called ACOT(chi), originally introduced for the proton, to deal with the heavy-quark thresholds. This defines our basic model (CJKL model), which gives a very good description of the experimental data on F2^gamma(x,Q^2), for both Q^2 and x dependences. For comparison we perform a standard fit using the Fixed Flavour-Number Scheme (FFNS_CJKL model), updated with respect to the previous fits of this type. We show the superiority of the CJKL fit over the FFNS_CJKL one and other LO fits to the F2^gamma(x,Q^2) data. The CJKL model gives also the best description of the LEP data on the Q^2 dependence of the F2^gamma, averaged over various x-regions, and the F_2,c^gamma, which were not used directly in the fit. Finally, a simple analytic parametrization of the resulting parton densities obtained with the CJKL model is given., Comment: 43 pages, RevTeX4 using axodraw style, 3 tex and 12 postscript figures, version submitted to Phys. Rev. D, small text changes, one reference added, FORTRAN program available at http://www.fuw.edu.pl/~pjank/param.html and at http://www-zeuthen.desy.de/~alorca/id4.html

A high energy linear e^+e^- collider (LC) can also be used as a Photon Collider (PC), using Compton scattering of laser photons on the e^+/e^- beams. The leading order cross-section for the production of heavy quarks, e^+e^- -> e^+e^- Q(\bar{Q}) X, at high transverse momenta is calculated for both LC and PC modes. The sensitivity of this process to the parton distribution parametrizations of real photons, especially the gluon content, is tested for both modes., 8 pages, Latex using epsfig.sty, including 6 postscript figures. Contribution to Proceedings of the Workshop "Physics Studies for a Future Linear Collider", Rolf Heuer, Francois Richard and Peter Zerwas Eds., 2000, DESY 123F

Radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, improved in respect to our previous paper F. Cornet, P. Jankowski, M. Krawczyk and A. Lorca, Phys. Rev. D68, 014010 (2003), are presented. We perform three global fits to the F2γ data, using the LO DGLAP evolution equation. We improve the treatment of the strong coupling running and use lower values of ΛQCD, as we have found that the too high values adopted in the previous work caused the high χ2 of the fits. In addition to the modified FFNSCJKL model, referred to as FFNSCJK1 we analyse a FFNSCJK2 model in which we take into account the resolved-photon heavy-quark contribution. New CJK model with an improved high-x behaviour of the F2γ( ) x,Q2 is proposed. Finally, in the case of the CJK model we abandon the valence sum rule imposed on the VMD input densities. New fits give χ2 per degree of freedom about 0.25 better than the old results. All features of the CJKL model, such as the realistic heavy-quark distributions, good description of the LEP data on the Q2 dependence of the F2γ and on F2,cγ are preserved. Moreover we present results of an analysis of the uncertainties of the CJK parton distributions due to the experimental errors. It is based on the Hessian method used for the proton and very recently applied for the photon by one of us. Parton and structure function parametrizations of the best fits in both FFNSCJK and CJK approaches are made accessible. For the CJK model we provide also sets of test parametrizations which allow for calculation of uncertainties of any physical value depending on the real photon parton densities., This work was partly supported by the European Community's Human Potential Programme under contract HPRN-CT-2000-00149 Physics at Collider and HPRN-CT-2002-00311 EURIDICE. FC also acknowledges partial financial support by MCYT under contract FPA2000-1558 and Junta de Andalucía group FQM330. This work was partially supported by the Polish State Committee for Scientific Research (KBN), grant n. 1 P03B 040 26 and project n. 115/E-343/SPB/DESY/P-03/DWM517/2003-2005

Radiatively generated, LO quark (u,d,s,c,b) and gluon densities in the real, unpolarized photon, calculated in the CJK model being an improved realization of the CJKL approach, have been recently presented. The results were obtained through a global fit to the experimental F2^gamma data. In this paper we present, obtained for the very first time in the photon case, an estimate of the uncertainties of the CJK parton distributions due to the experimental errors. The analysis is based on the Hessian method which was recently applied in the proton parton structure analysis. Sets of test parametrizations are given for the CJK model. They allow for calculation of its best fit parton distributions along with F2^gamma and for computation of uncertainties of any physical value depending on the real photon parton densities. We test the applicability of the approach by comparing uncertainties of example cross-sections calculated in the Hessian and Lagrange methods. Moreover, we present a detailed analysis of the chi^2 of the CJK fit and its relation to the data. We show that large chi^2/DOF of the fit is due to only a few of the experimental measurements. By excluding them chi^2/DOF approx 1 can be obtained., 28 pages, 8 eps figures, 2 Latex figures; FORTRAN programs available at http://www.fuw.edu.pl/~pjank/param.html; table 10, figure 10 and section 6 corrected