Algebraic K-theory of quasi-smooth blow-ups and cdh descent

We construct a semi-orthogonal decomposition on the category of perfect complexes on the blow-up of a derived Artin stack in a quasi-smooth centre. This gives a generalization of Thomason's blow-up formula in algebraic K-theory to derived stacks. We also provide a new criterion for descent in Voevodsky's cdh topology, which we use to give a direct proof of Cisinski's theorem that Weibel's homotopy invariant K-theory satisfies cdh descent.Comment: 24 pages; to appear in Annales Henri Lebesgu

The cdh-local motivic homotopy category

We construct a cdh-local motivic homotopy category SH_cdh(S) over an arbitrary base scheme S, and show that there is a canonical equivalence between SH_cdh(S) and SH(S). We learned this result from D.-C. Cisinski.Comment: 6 pages, posted on author's webpage in 2019; to appear in JPA

The derived homogeneous Fourier transform

We study a derived version of Laumon's homogeneous Fourier transform, which exchanges G_m-equivariant sheaves on a derived vector bundle and its dual. In this context, the Fourier transform exhibits a duality between derived and stacky phenomena. This is the first in a series of papers on derived microlocal sheaf theory.Comment: 29 page

The curious case of urban population in Pakistan

In their examination of recently released census data, Saad Khan and Dr Muhammad Adeel write that not only has the urban population been undercounted, but that there exists an urban bias that is affecting vital service delivery to the rural and peri-urban populations in Pakistan

Strategies for prevention of road traffic injuries (RTIs) in Pakistan: situational analysis.

Road traffic injuries (RTIs) are one of the leading causes of death among productive age group. Using systems approach framework (SAF), current preventive strategies for RTI control were reviewed in Pakistan. A review of the literature was done using four international search engines. Only ten studies on preventive strategies for RTI stemming from Pakistan were found. The first Road Traffic Injuries Research Network (RTIRN) surveillance system for road traffic injuries was established in urban city (Karachi) in Pakistan has shown promise for injury control and should be scaled up to other cities. Enforcement of traffic laws on seat-belt and helmet wearing is poor. National Highway and Motorway Police Ordinance (2000) was one of the few legislative measure so far taken in Pakistan. Using SAF, efforts are required to implement interventions targeting human, vehicle design and also making environment safer for road users