Effect of water properties in thixotropic clay systems on biological activity Final report

Effect of water properties in thixotropic clay systems on biological activit

Effect of Water Properties in Thixotropic Clay Systems on Biological Activity Annual Report, 1965

Effect of water properties in thixotropic clay systems on biological activit

THE EFFECTS OF FARM PRICE SUPPORT POLICIES: HOW LEVEL IS THE PLAYING FIELD FOR GRAIN PRODUCERS IN NAMIBIA?

In Namibia historically high levels of support to the commercial farm sector have been reduced in recent years in line with general market liberalisation trends. However some support remains. At the same time more attention has been paid to supporting the previously neglected communal sector. The avowed aim of politicians is to ensure that grain producers in Namibia operate “on a level playing fieldâ€. This paper examines to what extent the policy support playing field has been levelled for all major types of grain producer in Namibia. A methodology is introduced for developing a common measure of the effects of price support across grain producers with subsistence and commercial objectives and across scales of operation ranging from 1 hectare to 300 hectares under grain crops. The finding show that the bulk of grain producers in Namibia, who farm most of the grain area, remain seriously disadvantaged compared to the fewer, larger farms. Ongoing discussions on outsourcing government support services to small farmers is likely to result in the playing field becoming more uneven and other compensating measures will need to be taken if politicians and decision makers are serious about “evening the playing field for allâ€.Agricultural and Food Policy, Crop Production/Industries,

A new approach to service provisioning in ATM networks

The authors formulate and solve a problem of allocating resources among competing services differentiated by user traffic characteristics and maximum end-to-end delay. The solution leads to an alternative approach to service provisioning in an ATM network, in which the network offers directly for rent its bandwidth and buffers and users purchase freely resources to meet their desired quality. Users make their decisions based on their own traffic parameters and delay requirements and the network sets prices for those resources. The procedure is iterative in that the network periodically adjusts prices based on monitored user demand, and is decentralized in that only local information is needed for individual users to determine resource requests. The authors derive the network's adjustment scheme and the users' decision rule and establish their optimality. Since the approach does not require the network to know user traffic and delay parameters, it does not require traffic policing on the part of the network

A Review of Papua New Guinea's Red Meat Industry

Livestock Production/Industries,

Hydrogen peroxide induced genomic instability in nucleotide excision repair-deficient lymphoblastoid cells

Copyright @ 2010 Gopalakrishnan et al; licensee BioMed Central Ltd.Background The Nucleotide Excision Repair (NER) pathway specialises in UV-induced DNA damage repair. Inherited defects in the NER can predispose individuals to Xeroderma Pigmentosum (XP). UV-induced DNA damage cannot account for the manifestation of XP in organ systems not directly exposed to sunlight. While the NER has recently been implicated in the repair of oxidative DNA lesions, it is not well characterised. Therefore we sought to investigate the role of NER factors Xeroderma Pigmentosum A (XPA), XPB and XPD in oxidative DNA damage-repair by subjecting lymphoblastoid cells from patients suffering from XP-A, XP-D and XP-B with Cockayne Syndrome to hydrogen peroxide (H2O2). Results Loss of functional XPB or XPD but not XPA led to enhanced sensitivity towards H2O2-induced cell death. XP-deficient lymphoblastoid cells exhibited increased susceptibility to H2O2-induced DNA damage with XPD showing the highest susceptibility and lowest repair capacity. Furthermore, XPB- and XPD-deficient lymphoblastoid cells displayed enhanced DNA damage at the telomeres. XPA- and XPB-deficient lymphoblastoid cells also showed differential regulation of XPD following H2O2 treatment. Conclusions Taken together, our data implicate a role for the NER in H2O2-induced oxidative stress management and further corroborates that oxidative stress is a significant contributing factor in XP symptoms. Resistance of XPA-deficient lymphoblastoid cells to H2O2-induced cell death while harbouring DNA damage poses a potential cancer risk factor for XPA patients. Our data implicate XPB and XPD in the protection against oxidative stress-induced DNA damage and telomere shortening, and thus premature senescence.This research is supported by the Defence Innovative Research Programme, Defence Science and Technology Agency, Singapore (POD: 0613592) and the Academic Research Fund, Ministry of Education, Singapore (T206B3108). Supported in part by a grant from British Council, PMI2 Connect (Grant Number: RC134)

Projective Representations of the Inhomogeneous Hamilton Group: Noninertial Symmetry in Quantum Mechanics

Symmetries in quantum mechanics are realized by the projective representations of the Lie group as physical states are defined only up to a phase. A cornerstone theorem shows that these representations are equivalent to the unitary representations of the central extension of the group. The formulation of the inertial states of special relativistic quantum mechanics as the projective representations of the inhomogeneous Lorentz group, and its nonrelativistic limit in terms of the Galilei group, are fundamental examples. Interestingly, neither of these symmetries includes the Weyl-Heisenberg group; the hermitian representations of its algebra are the Heisenberg commutation relations that are a foundation of quantum mechanics. The Weyl-Heisenberg group is a one dimensional central extension of the abelian group and its unitary representations are therefore a particular projective representation of the abelian group of translations on phase space. A theorem involving the automorphism group shows that the maximal symmetry that leaves invariant the Heisenberg commutation relations are essentially projective representations of the inhomogeneous symplectic group. In the nonrelativistic domain, we must also have invariance of Newtonian time. This reduces the symmetry group to the inhomogeneous Hamilton group that is a local noninertial symmetry of Hamilton's equations. The projective representations of these groups are calculated using the Mackey theorems for the general case of a nonabelian normal subgroup

Timing of progression from Chlamydia trachomatis infection to pelvic inflammatory disease: a mathematical modelling study

PMCID: PMC3505463The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1471-2334/12/187. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited