1,720,985 research outputs found
Overwintering index of two different ecotypes of honey bees (Apis mellifera L.) at a beekeeping farm near Zadar in Gorica
No full textSiva pčela (Apis mellifera carnica) izvorna je pasmina u Republici Hrvatskoj i nastanjuje više zemalja na području Europe. Uspješnost prezimljavanja pčela posljednjih desetak godina značajno se smanjuje uslijed različitih čimbenika kao što su bolesti i štetnici, klimatski i okolišni čimbenici, tehnologija pčelarenja i brojni drugi. Cilj rada je izračunati indeks prezimljavanja pčelinje zajednice s obzirom na genetiku, prezimljavanje u zajednicama značajno ovisi jesu li ispitivane zajednice na svojoj originalnoj lokaciji ili okolišno različitoj lokaciji. Istraživanje je provedeno od listopada 2022. do travnja 2023. godine na pčelinjaku OPG Zlatko Elveđi u Gorici kraj Zadra. Za istraživanje korištena je izvorna pasmina sive pčele. Jedne su zajednice tretirane oksalnom kiselinom koja je na principu ekološkog sredstva (organske kiseline). Druge zajednice su tretirane amitrazom (akaricid). U istraživanju prezimljavanja zajednica, utvrđena je manja brojnost pčela ali veća ujednačenost u zajednicama mediteranskog u odnosu na kontinentalni ekotip. Zajednice tretirane amitrazom su imale veću prosječnu snagu, ali i veću varijabilnost u usporedbi sa podacima o zajednicama tretiranim oksalnom kiselinom. Zajednice mediteranskog ekotipa imale su 32% više pčela u proljeće 2023. u odnosu na jesen 2022., dok su zajednice kontinentalnog ekotipa imale 20 % više pčela u istom razdobljuThe carniolan bee (Apis mellifera carnica) is a native race in the Republic of Croatia and inhabits several countries in Europe. The success of bee overwintering has significantly declined in the last decade due to various factors such as diseases, pests, climate and environmental factors, beekeeping techniques, and many others. The aim of this study is to calculate the overwintering index of honey bee colonies with regard to genetics; overwintering in colonies significantly depends on whether the examined colonies are in their original location or in an environmentally different location. The research was conducted from October 2022 to or in an environmentally different location. The research was conducted from October 2022 to April 2023 at the OPG Zlatko Elveđi in Gorica near Zadar. Two ecotypes of carniolan beesbees were used for the research. The aim was to monitor the overwintering of colonies comparing two ecotypes. Part of the colonies were treated with oxalic acid, other colonies were treated with amitraz (acaricide). Colonies of mediterranean ecotype colonies, had a lower population of bees with higher variability comparing to continental ecotype. Nevertheless, colonies treated with amitraz had a higher average strength but also greater variability, while colonies treated with oxalic acid showed a significantly higher number of bees. Colonies of mediterranean ecotype had 32% more bees in spring than in autumn 2022., with an increase in the number of bees in spring 2023 compared to autumn 2022, while colonies of continental ecotye had 20% more bees in the same period
The importance of honeybee wax in beekeeping and other industries
No full textPčelinji vosak je u povijesti imao važnu ulogu u svakodnevnom životu. Riječ vosak potječe od anglosaksonske riječi „weax“ što je značilo prirodni materijal, koji su se dobivao od pčelinjeg saća ali i za voskove dobivene iz biljaka. Proizvode ga pčele radilice u dobi od 12 do 18 dana, a najveće potrebe zajednice za novim voskom su u proljeće. Pčelinji vosak pčele koriste kao građevni materijal za izgradnju saća u kojem uzgajaju leglo, smještaju rezerve hrane te sudjeluje u komunikaciji jedinki u zajednici. Proizvodnja pčelinjeg voska zasniva se na pretapanju starog tamnog i/ili oštećenog saća, zaperaka, mednih poklopaca, građevnjaka i voštanog trusja. Pčelari zamjenjuju godišnje oko 30% starog saća u zajednicama. Većina voska se koristi za satne osnove, no koristi se i u kozmetičkoj industriji (25 – 30 %), farmaciji (25 – 30 %), proizvodnji svijeća (20 %) te prehrambenoj industriji i ostalo (10 – 20 %). Zbog svojih kemijsko fizikalnih svojstava zadržao je primjenu i u ostalim industrijama kao laštilo, premaz za drvene predmete, u voćarstvu za premaz nakon rezidbe, u tekstilnoj industriji i elektronici te brojnim drugim. Pčelinji vosak koji se vraća u pčelarstvo ne podliježe kontroli na rezidue pesticida i lijekova,koji se u njemu akumuliraju godinama. Rezidue pesticida i lijekova utječu na vitalnost i zdravlje legla i pčela. Patvorenje pčelinjeg voska predstavlja veliki problem na tržištu satnih osnova u svjetskim razmjerima. Satne osnove od patvorenog voska utječu na vitalnost i život pčela te mogu ugroziti zdravlje zajednice i zbog narušenih komunikacijskih uvjeta unutar zajednice, osim navedenog utječe na smanjenje proizvodnje ali i kakvoće meda.Historically beeswax has played an important role in everyday life. The word wax comes from the Anglo-Saxon word "weax", which meant a natural material, which was obtained from comb, but also for waxes obtained from plants. It is produced by worker bees 12 to 18 days old, colonies are producing wax in the spring. Bees use beeswax as a building material for building combs in which they rear brood, place food reserves and it is participating in communication of nestmates. The production of beeswax is based on the melting of old dark and/or damaged combs, honey caps and wax scum. Beekeepers replace annually about 30% of the old comb in the colonies. Most of the wax is used to produce wax foundation, but it is also used in the cosmetic industry (25-30%), pharmacy (25-30%), candle production (20%), the food industry and others (10-20%). Due to its chemical and physical properties, it has continued to be used in other industries as a varnish, a coating for wooden objects, in fruit growing as a coating after pruning, in the textile industry, electronics and many others. Beeswax that is returned to beekeeping is not subject to control for pesticide and drug medicine residues, which accumulate in the wax over years of use. Residues of pesticides and medicines affect the vitality and health of brood and bees. Adulteration of beeswax is a major problem in the wax foundation market on a global scale. Wax foundations made of adulterated wax affect the vitality and life of bees and can threaten the health of the colony due to impaired communication conditions within the community and negatively affect normal physiological development, and foreign substances affect the decreased production and quality of hone
Overwintering index of two different ecotypes of honey bees (Apis mellifera L.) at a beekeeping farm near Zadar in Gorica
No full textSiva pčela (Apis mellifera carnica) izvorna je pasmina u Republici Hrvatskoj i nastanjuje više zemalja na području Europe. Uspješnost prezimljavanja pčela posljednjih desetak godina značajno se smanjuje uslijed različitih čimbenika kao što su bolesti i štetnici, klimatski i okolišni čimbenici, tehnologija pčelarenja i brojni drugi. Cilj rada je izračunati indeks prezimljavanja pčelinje zajednice s obzirom na genetiku, prezimljavanje u zajednicama značajno ovisi jesu li ispitivane zajednice na svojoj originalnoj lokaciji ili okolišno različitoj lokaciji. Istraživanje je provedeno od listopada 2022. do travnja 2023. godine na pčelinjaku OPG Zlatko Elveđi u Gorici kraj Zadra. Za istraživanje korištena je izvorna pasmina sive pčele. Jedne su zajednice tretirane oksalnom kiselinom koja je na principu ekološkog sredstva (organske kiseline). Druge zajednice su tretirane amitrazom (akaricid). U istraživanju prezimljavanja zajednica, utvrđena je manja brojnost pčela ali veća ujednačenost u zajednicama mediteranskog u odnosu na kontinentalni ekotip. Zajednice tretirane amitrazom su imale veću prosječnu snagu, ali i veću varijabilnost u usporedbi sa podacima o zajednicama tretiranim oksalnom kiselinom. Zajednice mediteranskog ekotipa imale su 32% više pčela u proljeće 2023. u odnosu na jesen 2022., dok su zajednice kontinentalnog ekotipa imale 20 % više pčela u istom razdobljuThe carniolan bee (Apis mellifera carnica) is a native race in the Republic of Croatia and inhabits several countries in Europe. The success of bee overwintering has significantly declined in the last decade due to various factors such as diseases, pests, climate and environmental factors, beekeeping techniques, and many others. The aim of this study is to calculate the overwintering index of honey bee colonies with regard to genetics; overwintering in colonies significantly depends on whether the examined colonies are in their original location or in an environmentally different location. The research was conducted from October 2022 to or in an environmentally different location. The research was conducted from October 2022 to April 2023 at the OPG Zlatko Elveđi in Gorica near Zadar. Two ecotypes of carniolan beesbees were used for the research. The aim was to monitor the overwintering of colonies comparing two ecotypes. Part of the colonies were treated with oxalic acid, other colonies were treated with amitraz (acaricide). Colonies of mediterranean ecotype colonies, had a lower population of bees with higher variability comparing to continental ecotype. Nevertheless, colonies treated with amitraz had a higher average strength but also greater variability, while colonies treated with oxalic acid showed a significantly higher number of bees. Colonies of mediterranean ecotype had 32% more bees in spring than in autumn 2022., with an increase in the number of bees in spring 2023 compared to autumn 2022, while colonies of continental ecotye had 20% more bees in the same period
FIZIKALNO KEMIJSKE ODLIKE MEDA OD VRIJESKA(Satureja spp.) I DRAČE (Palliurus spina Christi)
No full textPrema podacima FAO-a u svijetu je u 2011. godini proizvedeno 1.636.399 tona meda. Uzrok tolike razlike u podatcima leži u tome što se u službenu statistiku bilježi samo registrirana proizvodnja. Jedan od najvećih proizvođača ali i uvoznika meda je Europa. Zbog svoje relativno visoke cijene med se često patvori. Kako bi se to spriječilo doneseni su pravilnici i zakoni koji se odnose na kvalitetu meda. Zbog svojih brojnih značajki med se koristi u raznovrsne svrhe i predmet je brojnih istraživanja. Cilj ovoga rada je bio proučiti fizikalno kemijska svojstva meda koja se proizvode na jednom poljoprivrednom gospodarstvu. U istraživanju su analizirane dvije vrste meda iz 2011. i 2012. godine, med od drače (Paliurus spina christi) i vrijeska (Satureja spp.). Pri ispitivanju su se koristile metode prema Bučaru (laboratorij Srednje škole Lovre Montija u Kninu), za određivanje reducirajućih, nereducirajućih i ukupnih šećera u medu se kosristila Ernst-Lynon-ova metoda. U istraživanju su se ispitivali slijedeći parametri: refraktometrijsko određivanje šećera, pH meda, električna provodnost meda, ukupne kiseline te reducirajući i nereducirajući šećeri. Srednja vrijednost udjela vode u ispitivanim uzorcima meda od drače je iznosila 19. 5%, a kod meda od vrijeska 19 %. Vrijednosti za električnu provodnost su se kretale za med od vrijeska 400-620 mS/cm dok je ta vrijednost za med od drače bila ista i iznosila je 840 mS/cm. Vrijednosti za pH meda od drače su se kretale od 4.76-5.55, a za med od vrijeska 3.55-4.55. Ukupne kiseline kod meda od vrijeska su se kretale od 1.74-2.4 g/L, a za med od drače od 1.02-1.5 g/L. Udio reducirajućih šećera za med od drače se kretao od 58.72-70.71 %, a za med od vrijeska je iznosio 65.16-75.64 %, dok se udio nereducirajućih šećera za med od drače kretao od 5.29-13.04 %, a kod meda od vrijeska je iznosio od 1.49-3.98 %. Vrijednosti ukupnih šećera su iznosile za med od drače 71.76-76.00 % dok se ta vrijednost kod meda od vrijeska kretala od 66.65-79.62 %
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
