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Wired warfare 3.0: protecting the civilian population during cyber operations
As a general matter, international humanitarian law is up to the task of providing the legal framework for cyber operations during an armed conflict. However, two debates persist in this regard, the resolution of which will determine the precise degree of protection the civilian population will enjoy during cyber operations. The first revolves around the meaning of the term “attack” in various conduct of hostilities rules, while the second addresses the issue of whether data may be considered an object such that operations destroying or altering it are subject to the prohibition on attacking civilian objects and that such effects need be considered when considering proportionality and the taking of precautions in attack. Even if these debates were to be resolved, the civilian population would still face risks from the unique capabilities of cyber operations. This article proposes two policies which parties to a conflict should consider adopting in order to ameliorate such risks. They are both based on the premise that military operations must reflect a balance between military concerns and the interest of States in prevailing in the conflict
Magnetization reversal and local switching fields of ferromagnetic Co/Pd microtubes with radial magnetization
Three-dimensional nanomagnetism is a rapidly growing field of research covering both noncollinear spin textures and curved magnetic geometries including microtubular structures. We spatially resolve the field-induced magnetization reversal of free-standing ferromagnetic microtubes utilizing multifrequency magnetic force microscopy (MFM). The microtubes are composed of Co/Pd multilayer films with perpendicular magnetic anisotropy that translates to an anisotropy with radial easy axis upon rolling-up. Simultaneously mapping the topography and the perpendicular magnetostatic force derivative, the relation between surface angle and local magnetization configuration is evaluated for a large number of locations with slopes exceeding 45 degrees. The angle-dependence of the switching field is concurrent with the Kondorsky model, i.e., the rolled-up nanomembrane behaves like a planar magnetic film with perpendicular anisotropy and a pinning dominated magnetization reversal. Additionally, we discuss methodological challenges when detecting magnetostatic force derivatives near steep surfaces
Self-consistent model of unipolar transport in organic semiconductor diodes: accounting for a realistic density-of-states distribution
A self-consistent, mean-field model of charge-carrier injection and unipolar
transport in an organic semiconductor diode is developed utilizing the
effective transport energy concept and taking into account a realistic
density-of-states distribution as well as the presence of trap states in an
organic material. The consequences resulting from the model are discussed
exemplarily on the basis of an indium tin oxide/organic semiconductor/metallic
conductor structure. A comparison of the theory to experimental data of a
unipolar indium tin oxide/poly-3-hexyl-thiophene/Al device is presented.Comment: 6 pages, 2 figures; to be published in Journal of Applied Physic
Self consistent theory of unipolar charge-carrier injection in metal/insulator/metal systems
A consistent device model to describe current-voltage characteristics of
metal/insulator/metal systems is developed. In this model the insulator and the
metal electrodes are described within the same theoretical framework by using
density of states distributions. This approach leads to differential equations
for the electric field which have to be solved in a self consistent manner by
considering the continuity of the electric displacement and the electrochemical
potential in the complete system. The model is capable of describing the
current-voltage characteristics of the metal/insulator/metal system in forward
and reverse bias for arbitrary values of the metal/ insulator injection
barriers. In the case of high injection barriers, approximations are provided
offering a tool for comparison with experiments. Numerical calculations are
performed exemplary using a simplified model of an organic semiconductor.Comment: 21 pages, 8 figure
Economic inequalities in burden of illness, diagnosis and treatment of five long-term conditions in England: panel study
We compared the distribution by wealth of self-reported illness burden (estimated from validated scales, biomarker and reported symptoms) for angina, cataract, depression, diabetes and osteoarthritis, with the distribution of self-reported medical diagnosis and treatment. We aimed to determine if the greater illness burden borne by poorer participants was matched by appropriately higher levels of diagnosis and treatment
Spectroscopic biomedical imaging with the Medipix2 detector
This study confirms that the Medipix2 x-ray detector enables spectroscopic bio-medical plain radiography. We show that the detector has the potential to provide new, useful information beyond the limited spectroscopic information of modern dual-energy computed tomography (CT) scanners. Full spectroscopic 3D-imaging is likely to be the next major technological advance in computed tomography, moving the modality towards molecular imaging applications. This paper focuses on the enabling technology which allows spectroscopic data collection and why this information is useful. In this preliminary study we acquired the first spectroscopic images of human tissue and other biological samples obtained using the Medipix2 detector. The images presented here include the clear resolution of the 1.4mm long distal phalanx of a 20-week-old miscarried foetus, showing clear energy-dependent variations. The opportunities for further research using the forthcoming Medipix3 detector are discussed and a prototype spectroscopic CT scanner (MARS, Medipix All Resolution System) is briefly describe
Stationary Velocity and Charge Distributions of Grains in Dusty Plasmas
Within the kinetic approach velocity and charge distributions of grains in
stationary dusty plasmas are calculated and the relations between the effective
temperatures of such distributions and plasma parameters are established. It is
found that the effective temperature which determines the velocity grain
distribution could be anomalously large due to the action of accelerating ionic
bombarding force. The possibility to apply the results obtained to the
explanation of the increasing grain temperature in the course of the
Coulomb-crystal melting by reduction of the gas pressure is discussed. This
paper was received by Phys.Rev.Lett. on 11 August 1999. As potential referees
the authors offered to Editor the following persons: V.N.Tsytovich, Russia;
R.Bingham, UK; D.Resendes, Portugal; G.Morfill, P.Shukla, Y.M.Yu., Germany.Comment: 8 pages, no figure
Events in Early Life are Associated with Female Reproductive Ageing: A UK Biobank Study.
The available oocyte pool is determined before birth, with the majority of oocytes lost before puberty. We hypothesised that events occurring before birth, in childhood or in adolescence ('early-life risk factors') could influence the size of the oocyte pool and thus the timing of menopause. We included cross-sectional data from 273,474 women from the UK Biobank, recruited in 2006-2010 from across the UK. We analysed the association of early menopause with events occurring before adulthood in 11,781 cases (menopause aged under 45) and 173,641 controls (menopause/pre-menopausal at ≥ 45 years), in models controlling for potential confounding variables. Being part of a multiple birth was strongly associated with early menopause (odds ratio = 1.42, confidence interval: 1.11, 1.82, P = 8.0 × 10(-9), fully-adjusted model). Earlier age at menarche (odds ratio = 1.03, confidence interval: 1.01, 1.06, P = 2.5 × 10(-6)) and earlier year of birth were also associated with EM (odds ratio = 1.02, confidence interval: 1.00, 1.04, P = 8.0 × 10(-6)). We also confirmed previously reported associations with smoking, drinking alcohol, educational level and number of births. We identified an association between multiple births and early menopause, which connects events pre-birth, when the oocyte pool is formed, with reproductive ageing in later life.This research has been conducted using the UK Biobank Resource. This work was generously supported by a Wellcome Trust Institutional Strategic Support Award [WT097835MF to University of Exeter].This is the final version of the article. It first appeared from Nature Publishing Group via http://dx.doi.org/10.1038/srep2471
Self-consistent analytical solution of a problem of charge-carrier injection at a conductor/insulator interface
We present a closed description of the charge carrier injection process from
a conductor into an insulator. Common injection models are based on single
electron descriptions, being problematic especially once the amount of
charge-carriers injected is large. Accordingly, we developed a model, which
incorporates space charge effects in the description of the injection process.
The challenge of this task is the problem of self-consistency. The amount of
charge-carriers injected per unit time strongly depends on the energy barrier
emerging at the contact, while at the same time the electrostatic potential
generated by the injected charge- carriers modifies the height of this
injection barrier itself. In our model, self-consistency is obtained by
assuming continuity of the electric displacement and the electrochemical
potential all over the conductor/insulator system. The conductor and the
insulator are properly taken into account by means of their respective density
of state distributions. The electric field distributions are obtained in a
closed analytical form and the resulting current-voltage characteristics show
that the theory embraces injection-limited as well as bulk-limited
charge-carrier transport. Analytical approximations of these limits are given,
revealing physical mechanisms responsible for the particular current-voltage
behavior. In addition, the model exhibits the crossover between the two
limiting cases and determines the validity of respective approximations. The
consequences resulting from our exactly solvable model are discussed on the
basis of a simplified indium tin oxide/organic semiconductor system.Comment: 23 pages, 6 figures, accepted to Phys.Rev.
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