The implications of large lepton-quark-leptoquark couplings for direct leptoquark searches at Large Hadron Collider (LHC) are addressed. It is shown that flavour physics constraints allow for sizeable couplings of leptoquarks to the Standard Model fermions if these interact exclusively with charged leptons and quarks of the same generation. The leptoquark production mechanisms at LHC are thoroughly discussed to demonstrate the importance of inclusion of a t-channel pair production and, in particular, a single leptoquark production if and when the leptoquark couplings are large. A recast of an existing CMS search at LHC for the second generation leptoquarks is accordingly presented. It is shown to yield the best direct limit to date on Yukawa coupling of a leptoquark that couples exclusively to a muon and a strange quark .

This paper discusses the problems associated with the negative effects that accompany blasting operations, and the certain conclusions were derived. One of the negative effects of blasting operations is the phenomenon of seismic action and its effects on the buildings and the environment. Shock waves, induced by blasting, could cause damages to the building facilities and the environment. Those shocks seem to be very unfavorable to both humans and the environment. Therefore, certain standards were developed that define permissible values of impacts on buildings and people in buildings. In Serbia, there are no standards for assessing the impact of such shock waves. The international regulations and standards, mostly Russian and German, will be used to solve this problem. This case study provides an overview the measurement of shock waves during blasting at the open pit Manastiriste near Topola in a function of the quantity of used explosives, their impact on the surrounding buildings with special reference to the Monastery of the Holy Archangel Michael, as well as the assessment of measurement results according to the appropriate scales in the world. Keywords blasting, shock waves, measurement, impact, seismics * University of Belgrade, Faculty of Mining and Geology, Djusina 7, 11000 Belgrade, Serbia, e-mail: sanjabajic@sezampro.com; radmila.gacina@rgf.rs; katarina.urosevic@rgf.rs; suzana.lutovac@rgf.bg.ac.rs