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A positive integer d = i = 1 r p i d i is said to be an exponential divisor or an e-divisor of n = i = 1 r p i n i > 1 if 𝑑𝑖 ∣ 𝑛𝑖 for all prime divisors 𝑝𝑖 of 𝑛. In addition, 1 is an e-divisor of 1. It is easy to see that ℤ+ is a poset under the e-divisibility relation. Utilizing this observation we show that e-convolution of arithmetical functions is an example of the convolution of incidence functions of posets. We also note that the identity, units and the Möbius function are preserved in this process.

Open access

Let (𝑃𝑛)𝑛≥0 and (𝑄𝑛)𝑛≥0 be the Pell and Pell–Lucas sequences. Let 𝑏 be a positive integer such that 𝑏 ≥ 2. In this paper, we prove that the following two Diophantine equations 𝑃𝑛 = 𝑏𝑑𝑃𝑚 + 𝑄𝑘 and 𝑃𝑛 = 𝑏𝑑𝑄𝑚 + 𝑃𝑘 with 𝑑, the number of digits of 𝑃𝑘 or 𝑄𝑘 in base 𝑏, have only finitely many solutions in nonnegative integers (𝑚, 𝑛, 𝑘, 𝑏, 𝑑). Also, we explicitly determine these solutions in cases 2 ≤ 𝑏 ≤ 10.

Open access
Society and Economy
Authors:
Srdana Táborosi
,
Jelena Rajković Avdija
,
Jasmina Poštin
,
Edit Terek Stojanović
,
Nemanja Berber
, and
Milan Nikolić

Abstract

The paper presents the results of research on the impact of national culture, Big Five personality traits, and emotional intelligence on job satisfaction in teleworkers. The impacts were also examined in conventionally employed, which enabled a comparison. The research was conducted in the countries of the Western Balkans and included 313 respondents. The job satisfaction of teleworkers is most positively influenced by humane orientation, performance orientation, agreeableness, conscientiousness, openness, self-regulation, and social skills. Self-awareness can act both positively and negatively, and neuroticism has a negative impact on job satisfaction. National culture has a greater impact on job satisfaction among conventionally employed rather than within teleworkers. Big Five personality traits work differently: extroversion has a greater impact on job satisfaction among conventionally employed, while agreeableness and conscientiousness have a greater impact on job satisfaction among teleworkers. Emotional intelligence has a greater impact on job satisfaction among conventionally employed rather than teleworkers. Teleworking employees are less influenced by the environment, and thus less influenced by national culture. Emotional intelligence helps conventionally employed work more, while teleworkers place higher value on the results of their work.

Open access

Abstract

During the past years, we found a new Coleophora taxon in Hungary that proved to be unknown for the fauna of the country. We identified the unknown specimens using combined information from morphological examination including the female genitalia and genetic analyses. We sequenced the Cytochrome Oxidase “COI” gene of the mitochondrial DNA, and used the resultant base-pair sequence for species identification, using the BOLD platform, and for preparing a phylogenetic tree with the most closely related taxa involved. Our results show that larval and adult morphology, genitalia structure, and the sequence of the COI region of the unknown specimens are most similar to those of Coleophora gazella Toll, 1952. The habitats of the species in Hungary are strongly isolated from the nearest population in Turkey (Anatolia). We also studied habitat characteristics and life history of the species, which are briefly presented in this paper. The article contains four figures and two tables.

Open access

Abstract

A new subgenus of leaf-beetles Chrysolina (Ambrostomima subgen. nov.) is described from Hengduan Mountains (Sichuan and Gansu, China). It is characterized by the following main characters: body metallic, mostly green mixed with purple or one-colored green; last maxillary palpomere elongate, narrow, similar in both sexes; elytral punctures arranged in more or less distinct rows or mostly irregular; elytral epipleura inclined outside; hind wings completely missing; pygidium without furrow in apical 1/2 in most species; tarsomeres 1–3 more or less broadened in male, narrow in female, with entire sole in both sexes.

The subgenus consists of 25 species: Chrysolina amica Lopatin, Ch. baimana Lopatin, Ch. davidiani Lopatin, Ch. korotjaevi Lopatin, Ch. luyoui Daccordi et Ge, Ch. matruelis Lopatin, Ch. mirabilis (Daccordi), Ch. nesterovae Lopatin, Ch. pingchuana Lopatin, Ch. purpureoviridis Lopatin, Ch. rotundata Lopatin, Ch. sichuanica Lopatin, Ch. sicieni Ge et Yang, Ch. songpana Lopatin, Ch. viridiopaca Lopatin, Ch. aurita sp. nov., Ch. auriviridis sp. nov., Ch. bellissima sp. nov., Ch. ferdinandoi sp. nov., Ch. korolevi sp. nov., Ch. latipes sp. nov., Ch. ovata sp. nov., Ch. pilula sp. nov., Ch. pulchra sp. nov., and Ch. tortilla sp. nov.

Types of all previously described species except Ch. luyoui are examined. Males of Ch. mirabilis and Ch. viridiopaca are examined and described for the first time. Key to species is compiled. Type localities of Ch. viridiopaca and Ch. songpana are corrected. Photographs of habitus and male aedeagi are presented for all species.

Open access

As many world languages, Turkic also has simple suffixes in terms of structure, as well as complex suffixes with controversial origins. Although some of these suffixes have been systematized and bound to certain rules, the emergence of some suffixes still remains a mystery. Old Uyghur, which is one of the historical periods of the Turkic language, has such an undeciphered suffix. The compound suffix of +DXrtI has been evaluated by some researchers to date; however, no definite conclusion has been reached regarding its origin and function. For this purpose, various structures in Altaic languages will be examined and a connection will be made between this suffix and the ‘extraordinary’ examples seen in Old Uyghur.

Restricted access

Abstract

Purpose

The present study compares the efficacy of refractive surgery using third-generation and sixth-generation laser vision correction procedures in terms of postoperative visual acuity. The goal of the authors was to determine whether advances in laser technology had improved patients' uncorrected visual acuity, as measured at six-month follow-ups.

Materials/Methods

Results were reported from one of Europe's leading laser eye clinics, which has performed an outstandingly high number of treatments (over 100,000). The results of the clinic's first 10,000 treatments and most recent 10,000 treatments were evaluated.

Results

The analysis was performed by treated dioptric range and age group. The raw six-month visual acuity results show a statistically significant improvement over the last 10,000 interventions. The treatments resulted in significant improvements in all groups compared to the previous technology. With the new devices, visual acuity increased to above 1.0 in young myopes. The best results were seen in patients between 18 and 45 years of age, in the dioptric range between −1.0 D and −6.0 D.

Conclusions

It can be concluded that advances in technology improved refractive outcomes in all patient groups. This conclusion has excellent reliability and predictability due to the particularly high number of cases.

Open access

Abstract

Elderberry pomace, a by-product generated by elderberry processing industries, may be a favourable resource for further utilisation due to its components of high nutritional quality. In our research, elderberry pomace extract (EP) was added to apple juice as natural food additive for controlling microbial spoilage and enriching antioxidant components.

During the 8-week storage period of enriched apple juice (EPA) and control apple juice samples antioxidant properties were evaluated using the FRAP assay, Folin–Ciocalteu method, and pH differentiation method. The amount of polyphenols components was quantified using an RP-HPLC method. The microbiological status of samples was studied by determining the total viable and yeast/mould counts. The EPA is an important source of polyphenol components and other bioactive compounds, and the results suggest that extract of elderberry pomace could be a promising natural preservative to improve microbiological stability during refrigerated storage and increase the quality of apple juice.

Open access