Search results for "bee"
showing 10 items of 628 documents
Isolation of Free Phenylide-like Carbanions with N-Heterocyclic Carbene Frameworks
2009
A series of 1,3-bis(2,6-diisopropylphenyl)-5-methyl-1,3-diaza-4,6-diborabenzenes with methyl, phenyl, and dimethylamino substituents on the ring boron atoms were prepared using the cyclocondensation reaction between N,N′-bis(2,6-diisopropylphenyl)trimethylsilylformamidine and the appropriately substituted 1,1-bis(organochloroboryl)ethane, followed by deprotonation of the cationic ring intermediate. The planar, heterocyclic benzene analogues could be further deprotonated at the other ring carbon using an additional equivalent of potassium hexamethyldisilazide to yield organometallic derivatives akin to the potassium phenylide. The potassium cations could be efficiently sequestered in both so…
Chrząszcze saproksyliczne Karkonoszy. Część I - wykaz gatunków
2016
Założenia. W północnej (polskiej) części Karkonoszy nie prowadzono dotychczas gruntownych studiów fauny związanej z obumierającymi drzewami i rozkładającym się drewnem, mimo że w latach osiemdziesiątych i dziewięćdziesiątych ubiegłego wieku środowisko tych gór zostało dotknięte klęską zamierania lasów. Do dzisiaj, w wyniku procesów rozpadu drzewostanów, utrzymuje się wysoki zapas martwych drzew i rozkładającego się drewna. Celem przeprowadzonych prac inwentaryzacyjnych było rozpoznanie chrząszczy saproksylicznych występujących w środowiskach leśnych Karkonoszy. Materiał i metody. Prace realizowano w latach 2013–2015 w 10 obiektach badawczych reprezentujących środowiska lasów regla dolnego, …
Chrząszcze (Coleoptera) Suwalskiego Parku Krajobrazowego: monografia
2020
The beetles of the Suwalski Landscape Park (NE Poland) were studied between the years 2006−2013. The park covers an area of 6338 ha. Various field methods were used including sweep netting, dip netting, catching by hand, investigation of potential foraging sites of saproxylic beetles, rearing of cambio- and xylophagous larvae from inhabited material and attracting to artificial light sources. On the basis of our field studies and literature data, 1052 beetle species from 70 families were recorded, of which 715 have not been previously reported in the Park. One species – Variimorda briantea – is new to the Masurian Lake Region. The most numerous families were: rove beetles Staphylinidae (208…
Exploratory behaviour is not related to associative learning ability in the carabid beetle Nebria brevicollis
2020
Recently, it has been hypothesised that as learning performance and animal personality vary along a common axis of fast and slow types, natural selection may act on both in parallel leading to a correlation between learning and personality traits. We examined the relationship between risk-taking and exploratory behaviour and associative learning ability in carabid beetle Nebria brevicollis females by quantifying the number of trials individuals required to reach criterion during an associative learning task (‘learning performance’). The associative learning task required the females to associate odour and direction with refugia from light and heat in a T-maze. Further, we assessed learning …
Northward range expansion requires synchronization of both overwintering behaviour and physiology with photoperiod in the invasive Colorado potato be…
2014
Abstract. Photoperiodic phenological adaptations are prevalent in many organisms living in seasonal environments. As both photoperiod and growth season length change with latitude, species undergoing latitudinal range expansion often need to synchronize their life cycle with a changing photoperiod and growth season length. Since adaptive synchronization often involves a large number of time-consuming genetic changes, behavioural plasticity might be a faster way to adjust to novel conditions. We compared behavioural and physiological traits in overwintering (diapause) preparation in three latitudinally different European Colorado potato beetle (Leptinotarsa decemlineata) populations reared u…
Qualitative characteristics of four Sicilian monofloral honeys from Apis mellifera ssp. sicula
2023
Four monofloral honeys, obtained from the Sicilian black bee by foraging on thistle, sulla, chestnut and eucalyptus, were studied. Results showed that the phenolic composition of chestnut honey was the highest (316 mg gallic acid equivalent GAE/kg), while that of sulla honey was the lowest (122 mg GAE/kg). Data confirmed a correlation between the total phenol content and colour intensity in chestnut honey, which was the darkest of the four samples. Sulla honey showed the highest antioxidant activity, while eucalyptus honey had the highest mineral content (K, Ca, Mg, and Na). Thistle honey showed the most intense floral and fruity aromas, as well as an intense -yellow colour. Principal compo…
Cuando la historia está presente: Argumentos a favor de la sociología histórica
2019
Sociology and history have maintained a discontinuous relationship and a permanent discussion. Classical sociology is intrinsically historical, but after the first theoretical synthesis the dialogue between both disciplines was extinguished and it has often been necessary to defend the need for the historical view in sociology from the margins of the dominant paradigm. However, as a specialty or subdiscipline, historical sociology has consolidated its own academic space and a strong theoretical, methodological and conceptual body. In Spain this process of institutionalization has not yet success. In this article we expose a few arguments in defense of historical sociology, both theoretical …
A deterministic simulation study of embryo marker-assisted selection for age at first calving in Nellore (Bos indicus) beef cattle
2007
Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:04:58Z No. of bitstreams: 1 S1415-47572007000400008.pdf: 85300 bytes, checksum: 7422029b120457123fb366c1bd71e758 (MD5) Made available in DSpace on 2013-08-22T19:04:58Z (GMT). No. of bitstreams: 1 S1415-47572007000400008.pdf: 85300 bytes, checksum: 7422029b120457123fb366c1bd71e758 (MD5) Previous issue date: 2007-01-01 Made available in DSpace on 2013-09-30T20:08:32Z (GMT). No. of bitstreams: 2 S1415-47572007000400008.pdf: 85300 bytes, checksum: 7422029b120457123fb366c1bd71e758 (MD5) S1415-47572007000400008.pdf.txt: 39461 bytes, checksum: 2796161439379a834535eeaff8aac2ba (MD5) Previous issue date: 2007-01-01 Submitt…
POPOLAMENTI MARGINALI DI FAGGIO E CAMBIAMENTI CLIMATICI IN SICILIA: CRITICITÀ ED EFFETTI DELL’APPLICAZIONE DI PRATICHE SELVICOLTURALI TRADIZIONALI NO…
2016
Il faggio (Fagus sylvatica) è una tipica specie medio-Europea; in Sicilia si rinvengono i boschi di faggio più meridionali d’Europa. La marginalità ecologica di questi boschi è particolarmente evidente nei pattern frammentati e isolati di questi soprassuoli, in prossimità del limite della vegetazione arborea e/o localizzati nelle condizioni topografiche meno favorevoli. Nel presente lavoro si mettono a confronto i parametri dendrometricostrutturali e lo stato di salute delle piante in soprassuoli delle Madonie, confrontando cedui di faggio recentemente sottoposti a pratiche di taglio e aree di controllo non trattate da tempo. Inoltre, questi aspetti sono stati messi in relazione con il grad…
Dispersion Forces and Counterintuitive Steric Effects in Main Group Molecules: Heavier Group 14 (Si-Pb) Dichalcogenolate Carbene Analogues with Sub-9…
2013
The synthesis and spectroscopic and structural characterization of an extensive series of acyclic, monomeric tetrylene dichalcogenolates of formula M(ChAr)2 (M = Si, Ge, Sn, Pb; Ch = O, S, or Se; Ar = bulky m-terphenyl ligand, including two new acyclic silylenes) are described. They were found to possess several unusual features—the most notable of which is their strong tendency to display acute interligand, Ch–M–Ch, bond angles that are often well below 90°. Furthermore, and contrary to normal steric expectations, the interligand angles were found to become narrower as the size of the ligand was increased. Experimental and structural data in conjunction with high-level DFT calculations, in…