Functional groups of hoverflies in Southeast Europe across different vegetation types

To better understand the relationship between biodiversity and ecosystem functioning, it is increasingly accepted that the focus of study needs to shift from taxonomic identity to the diversity of functional traits displayed by species within a community. Such an approach allows species to be grouped according to particular functional characteristics. Increasingly viewed as an extremely important group of model organisms, hoverflies have been the focus of a variety of ecological studies. Based on data regarding selected functional traits of hoverflies registered in Southeast Europe, the main aims of our study were to define hoverfly functional groups according to the similarity of these traits, as well as to compare the representation of delineated hoverfly functional groups among these vegetation types. We used fuzzy clustering to classify 568 SE European hoverfly species into five functional groups. The principle trait separating these functional groups was larval feeding type, followed by size of species range, flight ability, number of generations, inundation tolerance, and tolerance to human impact. For 9 of 11 vegetation types, the dominant functional group was characterized by species with good flight ability, having high human impact tolerance and more annual generations. The remaining two vegetation types, South-west Balkan sub-Mediterranean mixed oak forests and Mediterranean mixed forests, showed disparate dominance patterns, indicating that richness of functional groups is dependent on vegetation. Further investigation of whether and how established conservation measures enable recovery of the functional richness affected by habitat disturbance would help elucidate the importance of functional diversity in preserving biodiversity.Peer reviewe

Uticaj oblika i strukture čestica na tečljivost elektrolitičkog bakarnog praha II - eksperimentalna potvrda modela reprezentativne čestice praha

An analysis of the effects of the shape, surface structure and size distribution of particles on the flow ability of the copper powder was performed. It is shown that the most important property of the particles of a powder, regarding the flow ability of the powder, is the surface structure of the particles.Izvedena je analiza uticaja oblika, površinske strukture i raspodele veličina čestica na tečljivost bakarnog praha. Pokazano je da površinska struktura predstavlja najvažnije svojstvo čestice praha u odnosu na njegovu tečljivost

Kritična nasipna masa za tečenje praha bakra

A method for the determination of the critical apparent density, which permits the free flow of electrodeposited copper powder is discussed. It was found that powders the apparent density of which were larger than 2.3 g/cm3 exhibit free flow. This is in good agreement with the literature data.Razmatrana je metoda određivanja kritične nasipne mase, pri kojoj dolazi do tečenja elektrohemijski taloženog praha bakra. Nađeno je da tečenje postoji kod prahova čija je nasipna masa veća od 2.3 g/cm3, što je u saglasnosti sa literaturnim podacima

NEW FINDINGS OF HOVERFLY FAUNA (DIPTERA: SYRPHIDAE) OF THE WESTERN PART OF SERBIA (ZLATIBOR AND RAŠKA DISTRICTS)

During a three year systematic sampling of the hoverfly fauna in highlands of western Serbia, 150 hoverfly species of 51 genera were recorded for this region. Eumerus ovatus Loew, 1848, new to the fauna of Serbia, was recorded on mountain Zlatibor. Additionally, 4 new hoverfly species from the genus Merodon Meigen, 1803 were found, awaiting species descriptions. The most species-rich areas in the investigated region are SW part of Mt. Golija and SE part of Mt. Zlatar. These mountains also have the highest number of protected and strictly protected species. In order to preserve this high local diversity of hoverflies, protection of these areas, as well as proper conservation management are of crucial importance

Meat quality characteristics of DurocxYorkshire, DurocxYorkshirexwild boar and wild boar

Chemical composition, pH value, fatty acids profile, cholesterol content, color and sensory analysis of pork meat from Duroc x Yorkshire (D x Y), Duroc x Yorkshire x wild boar (D x Y x WB) crossbreeds and wild boars (WB) was investigated. Samples for all tests were taken from m. longissimus dorsi. Chemical composition and pH value were tested by ISO methods. Fatty acid and cholesterol determination was performed by gas chromatography technique with external standard method. Color was determined instrumentally using the thristimulus colourimeter. The overall sensoric quality (appearance, texture and smell) of samples of raw meat was evaluated. In evaluation of results the scoring system was used. In chemical composition (moisture, fat, protein, ash) and pH values statistically significant difference was noted (p<0,05) between each of the examined groups. Also, among all the examined groups statistically significant difference (p<0,05) was found for fatty acids and cholesterol content. Measurment of the color of meat from all three groups showed that the L*, a * b *, Chroma and Hue angle were also statistically significantly different (p<0,01)

Insights from the preimaginal morphology of the constans species‑group, to reveal novel morphological patterns of the Merodon albifrons‑evolutionary lineage (Diptera, Syrphidae)

Merodon triangulum Vujić, Radenković & Hurkmans, 2020 is a European endemic hoverfly species belonging to Merodon constans species-group, inside albifrons-lineage. The distribution of this species is known to be mostly central Europe and Balkan peninsula and it has been categorized as Near Threatened in the European IUCN red list of hoverflies; this paper cites the species for the first time in Ukraine (western Ukraine, specifically). In the present study, the preimaginal stages of this species are described and figured using Scanning Electron Microscopy. The material used for the descriptions were larvae collected in Ukraine and Serbia feeding inside underground storage organs of the spring snowflake Leucojum vernum L., 1753. This morphological description constitutes the first one inside the constans species-group, and the sixth description of the albifrons-lineage, in which there is only one species-group left to have at least one species of the preimaginal stages described (i.e., ruficornis species-group). The descriptions were compared with the rest available of the genus, stating the diagnostical characters of the present species and the shared characters inside the lineage. The novel information provided on the trophic interaction between M. triangulum larvae and Leucojum bulbs is stated for the first time and further supports the association of the constans species-group with the underground storage organs of snowflakes and snowdrops (Galantheae) in their role as host plants.Partial financial support was received from the research department of the University of Alicante in the frame work of a predoctoral grant (UAFPU2019-03). In addition, the study has been partially supported by the Ministry of Science, Technological Development and Innovation of the Republic of Serbia (Grant No. 451-03-47/2023-01/200125 and Grant No. 451-03-47/2023-01/200358)

Fizičko modelovanje reprezentativnih čestica elektrohemijski istaloženog bakarnog praha

A method for the estimation of the size of the representative particle of a copper powder is given. Cross sections of representative particles of flowing and non-flowing powders estimated by this procedure are also presented.U radu je dat metod za procenu veličine reprezentativnih čestica bakarnog praha. Predstavljeni su poprečni preseci reprezentativne čestice tečljivog i netečljivog praha dobijeni korišćenjem ovog postupka

Uticaj oblika i strukture čestica na tečljivost elektrolitičkog bakarnog praha IV - unutrašnja struktura čestica praha

The structure of powder particleswas analysed by considering their cross sections. It was shown that the structure of powder particles of nonsieved flowing powders is sufficiently dense to produce a continuous surface, which does not allow the particles to jam and hence permits the free flow of nonsieved powder. It was also shown that the representative powder particle the elementary cell of which can be presented by a 3D-cross, describes the properties of the powder relative to its flowability well.Analizirana je struktura čestica praha razmatranjem njihovog poprečnog preseka Pokazano je da je struktura čestica nesejanog praha koji teče dovoljno gusta da obrazuje kontinualnu površinu, koja ne dozvoljava zaglavljivanje čestica i samim tim omogućava slobodno tečenje nesejanih prahova. Takođe je pokazano da reprezentativna čestica praha, čija se elementarna ćelija može predstaviti 3D-krstom, dobro opisuje osobine praha koje se odnose na tečljivost

Uticaj oblika i strukture čestica na tečljivost elektrolitičkog bakarnog praha I - modelovanje reprezentativne čestice praha

One of the most important properties of copper powder is its flow ability which depends on the shape and the structure of the powder particles. A procedure for the determination of a representative powder particle permitting the free flow of copper powder is proposed.Jedno od najvažnijih svojstava bakarnog praha je njegova tečljivost, koja zavisi od oblika i strukture čestica praha. Predložen je postupak za određivanje reprezentativne čestice praha koja obezbeđuje slobodno tečenje bakarnog praha

Uticaj oblika I strukture čestica na tečljivost elektrolitičkog bakarnog praha III - model površine reprezentativne čestice tečljivog bakarnog praha dobijenog elektohemijskim taloženjem reversnom strujom

The structure of the surface of copper powder particles is discussed and correlated with the lowest apparent density at which copper powder can still flow. It is shown that such structures can be easily obtained in the electrodeposition of powders in reversing current regimes.Razmatrana je struktura površine čestica bakarnog praha i korelisana s najmanjom nasipnom masom pri kojoj bakarni prah još uvek može da teče. Pokazano je da se takva struktura može lako dobiti elektrohemijskim taloženjem praha u režimu reversne struje