Reasonableness Meets Requirements: Regulating Security and Privacy in Software

Software security and privacy issues regularly grab headlines amid fears of identity theft, data breaches, and threats to security. Policymakers have responded with a variety of approaches to combat such risk. Suggested measures include promulgation of strict rules, enactment of open-ended standards, and, at times, abstention in favor of allowing market forces to intervene. This Note lays out the basis for understanding how both policymakers and engineers should proceed in an increasingly software-dependent society. After explaining what distinguishes software-based systems from other objects of regulation, this Note argues that policymakers should pursue standards-based approaches to regulating software security and privacy. Although engineers may be more comfortable dealing with strict rules, this Note explains why both policymakers and engineers benefit from pursuing standards over rules. The nature of software development prevents engineers from ever guaranteeing security and privacy, but with an effective regulatory standards framework complemented by engineers\u27 technical expertise, heightened security, and privacy protections can benefit society

On the scaling behaviour of cross-tie domain wall structures in patterned NiFe elements

The cross-tie domain wall structure in micrometre and sub-micrometre wide patterned elements of NiFe, and a thickness range of 30 to 70nm, has been studied by Lorentz microscopy. Whilst the basic geometry of the cross-tie repeat units remains unchanged, their density increases when the cross-tie length is constrained to be smaller than the value associated with a continuous film. This occurs when element widths are sufficiently narrow or when the wall is forced to move close to an edge under the action of an applied field. To a very good approximation the cross-tie density scales with the inverse of the distance between the main wall and the element edge. The experiments show that in confined structures, the wall constantly modifies its form and that the need to generate, and subsequently annihilate, extra vortex/anti-vortex pairs constitutes an additional source of hysteresis.Comment: 4 pages, 5 figures, accepted for publication in Europhysics Letters (EPL

Electrical observation of a tunable band gap in bilayer graphene nanoribbons at room temperature

We investigate the transport properties of double-gated bilayer graphene nanoribbons at room temperature. The devices were fabricated using conventional CMOS-compatible processes. By analyzing the dependence of the resistance at the charge neutrality point as a function of the electric field applied perpendicular to the graphene surface, we show that a band gap in the density of states opens, reaching an effective value of ~sim50 meV. This demonstrates the potential of bilayer graphene as FET channel material in a conventional CMOS environment.Comment: 3 pages, 3 figure

Die hantering van neweskikkers en onderskikkers in Afrikaanse woordeboeke

Die diskrepansie tussen die behoefte aan leksikografiese leiding met betrekking tot voegwoorde en die relatiewe onverskilligheid hierteenoor in terme van leksikografiese navorsing en praktyk het tot hierdie artikel aanleiding gegee, waarin die onbevredigende hantering van voegwoorde in Afrikaanse woordeboeke aangedui word en enkele konstruktiewe leksikografiese oplossings vir die hantering van hierdie woordsoortkategorie aan die hand gedoen word. 'n Eerste aanbeveling is dat die lemmata voegwoord, verbindingswoord, neweskikker, onderskikker en voegende bywoord meer diepgaande sintaktiese inligting, met genoeg voorbeelde (ook oor sinsgrense heen) voorsien. Daar behoort kruisverwysings van die spesifieke voegwoordlemmata na hierdie lemmata te wees. Die voorbeelde wat aangebied word, behoort ook tipiese leksikale en grammatiese patrone aan te dui, sowel as of hipotaktiese binding moontlik is of net inlywing. In aanleerderwoordeboeke kan die tipiese leksikale patrone in vet druk verskyn. Sorg moet gedra word in omvattende woordeboeke, soos WAT, om vinniger inligtingsherwinning tot gevolg te hê en leksikograwe behoort nie funksies gelyk te stel aan polisemiese betekenisonderskeidings nie. So is daar byvoorbeeld twee lemmas nodig by of aangesien dit 'n homoniem is wat duidelik aparte lemmas vereis. Sleutelwoorde: Leksikografie, Neweskikker, Korrelatiewe Neweskikker, Onderskikker, Eentalige Woordeboek, Hipotaktiese Binding, Inlywing, Komplementsinne, Grammatikale Leiding, Linguistiese Fundering, Woordorde, Klousintegrasie, Funksiewoor

Controlling the Morphology of Aggregates of an Amphiphilic Synthetic Receptor through Host-Guest Interactions

A new amphiphilic receptor containing a macrocyclic anionic headgroup and a single alkyl chain was prepared through an efficient templated synthesis. The interdependence of the aggregation behavior and the host-guest chemistry was studied. In the absence of any guest the terminus of the alkyl chain of the receptor is included inside the hydrophobic cavity of the macrocycle (as evident from 1H NMR studies) leading to self-assembly into micrometer-long nanotubes (as evident from TEM studies). The alkyl chain can be displaced by an acridizinium bromide guest (as evident from 1H NMR and ITC), which leads to a dramatic change in aggregate size and morphology (as evident from DLS). Studies of the solubilization of Nile red suggest that the resulting aggregates are micelles with a cmc of around 35 µM. These results represent a new addition to the still small number of water-soluble amphiphilic receptors and one of the first examples in which specific host-guest chemistry controls the size and shape of nanoscale aggregates.

Recent Developments in Coloring Matters

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Little Higgs Model Completed with a Chiral Fermionic Sector

The implementation of the little Higgs mechanism to solve the hierarchy problem provides an interesting guiding principle to build particle physics models beyond the electroweak scale. Most model building works, however, pay not much attention to the fermionic sector. Through a case example, we illustrate how a complete and consistent fermionic sector of the TeV effective field theory may actually be largely dictated by the gauge structure of the model. The completed fermionic sector has specific flavor physics structure, and many phenomenological constraints on the model can thus be obtained beyond gauge, Higgs, and top physics. We take a first look on some of the quark sector constraints.Comment: 14 revtex pages with no figure, largely a re-written version of hep-ph/0307250 with elaboration on flavor sector FCNC constraints; accepted for publication in Phys.Rev.