Various Properties of Sturmian Words

This overview paper is devoted to Sturmian words. The first part summarizes different characterizations of Sturmian words. Besides the well known theorem of Hedlund and Morse it also includes recent results on the characterization of Sturmian words using return words or palindromes. The second part deals with substitution invariant Sturmian words, where we present our recent results. We generalize one-sided Sturmian words using the cut-and-project scheme and give a full characterization of substitution invariant Sturmian words.

Specular sets

We introduce the notion of specular sets which are subsets of groups called here specular and which form a natural generalization of free groups. These sets are an abstract generalization of the natural codings of linear involutions. We prove several results concerning the subgroups generated by return words and by maximal bifix codes in these sets.Comment: arXiv admin note: substantial text overlap with arXiv:1405.352

THE EFFECT OF YUCCA SCHIDIGERA EXTRACT IN DIET OF RABBITS ON NUTRIENT DIGESTIBILITY AND QUALITATIVE PARAMETERS IN CAECUM

ABSTRACT The aim of this study was to determine the effects of yucca (Yucca schidigera) powder extract added to the rabbit feed mixtures. The animals of experimental group (EG1) were fed diet enriched with supplement of Yucca schidigera dry extract 5g/100 kg feed; rabbits of EG2 had diet enriched with yucca dry extract 20g/100 kg feed for 42 days. The control group (CG) was fed untreated pellet diet. The experiment was carried out on commercial hybrid Hycole rabbits. Between 65 and 70 days of age, 3 male rabbits from each group were selected for digestibility tests using the balance method. The faeces were collected individually during 5 consecutive days according to the European reference method for rabbit digestion trials. Chemical analysis of the diets and faeces for dry matter, crude protein, crude fibre, crude fat, nitrogen free extract, organic matter and starch was carried out according to the same method. The caecal samples from each of three slaughtered rabbits were collected for analysis; pH, VFA, ammonia-N and lactic acid were determined. The rabbits in our experiment showed the lowest coefficients of digestibility of crude fibre, and higher digestibility of crude protein, crude fat and organic matter, but the differences were not statistically significant comparing with control diet. The effect of yucca extract addition is manifested in reducing ammonia levels in the caecum of rabbits

On Words with the Zero Palindromic Defect

We study the set of finite words with zero palindromic defect, i.e., words rich in palindromes. This set is factorial, but not recurrent. We focus on description of pairs of rich words which cannot occur simultaneously as factors of a longer rich word

The impact of managerial characteristics on business strategies under the environmental change: an investigation of the Israeli diamond industry

The changing business environment has required firms to adopt new strategies to facilitate efficient organizational adaptation. Previous upper echelons studies suggested that the demographic characteristics of top managers influence their choice of strategies, and ultimately the firms’ performance. These studies tended to examine firms in a homogenous way. The characteristics of family-owned firms, together with the unique external environment within which they operate, have been largely ignored. This study aims to fill this gap and examine the relationships between the top managers’ characteristics and their choice of exchange strategy within the diamond industry in light of the environmental changes. This paper illustrates the evolutionary stages of the diamond industry and how players adjust their strategies in-line with the environment. We interviewed 100 diamond firm managers to gather the empirical data. The results have shown that certain managerial characteristics, such as family background and marketing experience, have positively influenced the choice of using the arm’s length market exchange strategies. Our findings have also reflected that the relationship between managers’ characteristics and strategic choice is social and normative. Many managers follow the family or community traditions and imitate other key industry players in order to achieve legitimacy from the stakeholders and improve competitiveness

Various Properties of Sturmian Words

This overview paper is devoted to Sturmian words. The first part summarizes different characterizations of Sturmian words. Besides the well known theorem of Hedlund and Morse it also includes recent results on the characterization of Sturmian words using return words or palindromes. The second part deals with substitution invariant Sturmian words, where we present our recent results. We generalize one-sided Sturmian words using the cut-and-project scheme and give a full characterization of substitution invariant Sturmian words.

Bryophytes and macro-algal growths as a part of macrophyte monitoring in rivers used for ecological assessment

Altogether, 62 taxa of macrophytes including 18 bryophytes and 16 macro-algal growths were determined at 87 survey sites (73 rivers) representing the both ecoregions in Slovakia (Pannonian and Carpathian) during the years 2010–2013. Bryophytes represented the dominant community in the Carpathians, while the occurrence of macro-algal growths was relatively balanced in both ecoregions. Ordination analyses (DCA) showed an obvious shift within studied survey sites from vascular plants to bryophytes, while macro-algal growths were more or less uniform distributed in the whole ordination space. Based on stepwise (forward) selection in CCA, altitude and water surfaces as a land use type were the main environmental factors responsible for this pattern and explained 13.7% of the variability. Variation partitioning showed that the shares of environmental variables on the total variation decreased in the following order: both groups together 8.3% (landscape and geographical variables, physicochemical variables), followed by landscape and geographical variables (5.8%) and purely physicochemical variables which had an insignificant effect on macrophyte composition. The importance of both groups (bryophytes and macro-algal growths) in ecological assessment was also confirmed by their contribution to the mean IBMR value determined for each water body type. Anyway, our study showed that their contribution to ecological assessment is not focused only on small mountain streams where they are dominant. They may obviously affect ecological assessment also in many water body types in lowland rivers and large upland rivers as well