Results 41 to 50 of about 158,284 (274)

Convergent Loss of Prothoracicotropic Hormone, A Canonical Regulator of Development, in Social Bee Evolution

Frontiers in Physiology, 2022
The evolution of insect sociality has repeatedly involved changes in developmental events and their timing. Here, we propose the hypothesis that loss of a canonical regulator of moulting and metamorphosis, prothoracicotropic hormone (PTTH), and its ...
Claudinéia P. Costa, Naoki Okamoto, Naoki Okamoto, Michael Orr, Naoki Yamanaka, S. Hollis Woodard   +5 more
doaj   +1 more source

Calcareous grassland fragments as sources of bee pollinators for the surrounding agricultural landscape

Global Ecology and Conservation, 2021
In Central Europe, agricultural intensification has led to increasing fragmentation and loss of semi-natural habitats. In turn, ecosystem services such as pollination are being lost when insect pollinators depend on semi-natural habitats.
Felix Klaus, Teja Tscharntke, Johannes Uhler, Ingo Grass   +3 more
doaj   +1 more source

Direct Access to Chiral Piperidines by Enantioselective HAT‐Initiated C(sp3)─H Oxidation

Angewandte Chemie, EarlyView.
The direct desymmetrization of piperidines is achieved through manganese‐catalyzed enantioselective α‐C(sp3)─H oxidation with hydrogen peroxide, affording versatile chiral N,O‐acetals in good yields and with high enantio‐ and diastereoselectivity. These intermediates provide access to diverse functionalized piperidines with retention of chirality ...
Sethuraman Muthuramalingam, Josep M. Luis, Arnau Call, Quentin Lefebvre, Matthew S. Sigman, Miquel Costas   +5 more
wiley   +2 more sources

Description and validation of an improved method to feed solitary bees (Osmia spp.) known amounts of pesticides

Ecotoxicology and Environmental Safety, 2023
Pesticide exposure is an important driver of bee declines. Laboratory toxicity tests provide baseline information on the potential effects of pesticides on bees, but current risk assessment schemes rely on one species, the highly social honey bee, Apis ...
C. Azpiazu, S. Hinarejos, G. Sancho, S. Albacete, F. Sgolastra, C.A.H. Martins, X. Domene, J. Benrezkallah, A. Rodrigo, X. Arnan, J. Bosch   +10 more
doaj   +1 more source

Oocyte size, egg index, and body lipid content in relation to body size in the solitary bee Megachile rotundata [PDF]

PeerJ, 2014
Females of solitary, nest-provisioning bees have relatively low fecundity, but produce large eggs as part of their overall strategy of investing substantially in each offspring.
Kevin M. O’Neill, Casey M. Delphia, Ruth P. O’Neill   +2 more
doaj   +2 more sources

Scientific Opinion on the science behind the development of a risk assessment of Plant Protection Products on bees (Apis mellifera, Bombus spp. and solitary bees)

EFSA Journal, 2012
The PPR Panel was asked to deliver a scientific opinion on the science behind the development of a risk assessment of plant protection products on bees (Apis mellifera, Bombus spp. and solitary bees).
EFSA Panel on Plant Protection Products and their Residues (PPR)
doaj   +1 more source

Survival rate and changes in foraging performances of solitary bees exposed to a novel insecticide

Ecotoxicology and Environmental Safety, 2021
Solitary bees are among the most important pollinators worldwide however population declines especially in croplands has been noticed. The novel pesticide sulfoxaflor is a competitive modulator of nicotinic acetylcholine receptors (nAChR) in insects ...
Samuel Boff, Ricarda Scheiner, Josué Raizer, Daniela Lupi   +3 more
doaj   +1 more source

Solitary-wave solutions of the Degasperis-Procesi equation by means of the homotopy analysis method [PDF]

, 2010
The homotopy analysis method is applied to the Degasperis-Procesi equation in order to find analytic approximations to the known exact solitary-wave solutions for the solitary peakon wave and the family of solitary smooth-hump waves.
Abbasbandy, S., Parkes, E.J.
core   +4 more sources

Local management and landscape effects on diversity of bees, wasps and birds in urban green areas [PDF]

, 2008
Today almost all ecosystems on Earth are directly or indirectly influenced by human activity. Most species occur in ecosystems that are managed by humans and only a small fraction of biodiversity exists in protected areas.
Ahrné, Karin
core   +1 more source

A strong immune response in young adult honeybees masks their increased susceptibility to infection compared to older bees [PDF]

, 2012
Honeybees, Apis mellifera, show age-related division of labor in which young adults perform maintenance ("housekeeping") tasks inside the colony before switching to outside foraging at approximately 23 days old. Disease resistance is an important feature
Baxter, LA, James C Bull, Bull James C., Ryabov, EV, Laura A. Baxter, Baxter Laura A., Mead, A, Pell, JK, Judith K. Pell (107694), Laura A Baxter, Osborne Juliet L., Ryabov, Eugene V., Chandler, D, Prince Gill, Judith K. Pell¤b, Juliet L Osborne, Prince, G, Osborne, Juliet L., Osborne, JL, Judith K Pell, Cunjin Zhang, Prince, Gillian, Dave Chandler (107700), Zhang, C., Laura A. Baxter (107691), Ryabov, E. V., Zhang Cunjin, Dave Ch, Chandler Dave, Baxter, L. A., Juliet L. Osborne¤c, James C. Bull (107677), Pell Judith K., Ryabov Eugene V., Baxter, Laura, James Bull, Chandler, Dave, Eugene V. Ryabov (107680), Mead, A. (Andrew), Zhang, Cunjin, Eugene V Ryabov, Andrew Mead, Cunjin Zhang (107690), James C. Bull, Mead Andrew, Chandler, D., Gill Prince, Bull, James C., Prince, G., Pell, Judith K., Dave Chandler, Pell, J. K., Osborne, J. L., Juliet L. Osborne (107697), Zhang, C, Andrew Mead (107686), Mead, A., Bull, JC, Bull, J. C., Eugene V. Ryabov, Gill Prince (107683)   +60 more
core   +1 more source