Surveillance for familial and hereditary pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma is one of the most lethal forms of cancer. This book describes the outcome of long-term surveillance for p16-Leiden/CDKN2A mutation carriers. Further evaluating the role of precursor lesions, including IPMN and PanIN in the development of PDAC. It is also common knowledge that hereditary cancer is associated with the development of multiple tumors due to the fact that all body cells carry the inherited mutation. Therefore the third aid was to evaluate the risk of multiple PDAC in carriers of a p16-Leiden founder mutation. The fourth aim was to evaluate cost-effectiveness of surveillance. During our surveillance study, the program unexpectedly detected also other types of cancer than PDAC including benign lesions (incidentaloma). The fifth aim was to evaluate what type of cancers and benging lesions were detected and whether surveillance and early detection offered any benefit. The final aim was to describe the dilemmas in the management of screen-detected lesions that we experienced during our surveillance program. Universiteit Leiden; HIX; ABN AmroLUMC / Geneeskund

Extent of Extension Service Delivery for Agro-pastoralists in Niger State,Nigeria

The study examines the extent of agricultural extension services deleivery to agro-pastoralists in Niger State. Nigeria. Primary data were collected through field survey from agropastorialist from three purposely selected Local Government Areas in Niger State. Katcha, Paiko and Wushishi LGA’s were purposely selected by making sure they were in different agricultural zones of the Niger State namely Zone I, II and III respectively. Twenty percent of the agropastoralists house-hold population was sampled from each of three LGA randomly. A total of 210 household heads were sampled and interviewed using a semi structured survey instrument administered by trained enumerators who understood the local language. Both descriptive and inferential statistics were employed to analyse the data. Results revealed that all (100%) of the household heads were all males and 67.7% acquired adult education while agro-pastoralism was the major occupation (98.1%). Majority (98.1%) of the agro-pastoralists claimed they were of Fulani ethnic group. Information on out break of diseases (mean=3.9); provision of grazing reserves (mean=3.7) were reported high. Majority (99.5%) of the respondents opined that lack of easy access to vaccines and non- proximity of veterinary clinic were major constraints. In the testing of hypotheses, Pearson Product Moment Correlation (PPMC) showed a significant positive relationship between extent of extension service provision and the following variables namely Age (r =0.172; p<0.05), number of wives (r =0.163; p<0.05), number of children (r =0.222 and; p<0.05), and number of cows owned (r =0.221; p<0.05).  The result of Chi-square analysis shows that there was a significant relationship between Extent of extension provision and the settlement type (X2 =10.21; p<0.05), Extent of extension provision and educational level (X2 =12.20;p<0.05). It was recommended that government should make adequate arrangement for provision of neccessary infra-structure in the already gazzeted grazing reserve most especially vetinery clinics and make vaccine available and affordable for them. There is need to produce more radio programmes and also encourage formation of radio listening group since is one of the major source of information to their production system. Keywords: Agriculture, Extension service delivery, agropastoralist

The Effect of Strain Rate on Electrical and Mechanical Characteristics of Pure Aluminum Using Equal Channel Angular Pressing (ECAP)

-During equal-channel angular pressing (ECAP), the effect of severe plastic deformation (SPD) rate on both the electrical (electrical resistance, denoted as (R),Ω and The electrical resistivity denoted as (ρ), Ω.m) and mechanical characteristics (Ultimate Tensile Strength abbreviated as (UTS), MPa and Micro-Hardness measured in Vickers Hardness Number, abbreviated as VHN) of pure aluminum alloy are experimentally investigated.ECAP was used to improve the pure aluminum alloy\u27s microstructure at room temperature, which had samples with square cross sections. The findings indicate that as the rate of strain decreases from 0.3 to 0.1 s^-1, there is a gradual increase in both Ultimate Tensile Strength (UTS) and hardness, with the highest values observed at a strain rate of 0.025 s^-1.This study empirically explored the influence of ECAP on the macrostructure, microstructure, mechanical properties, and electrical properties of pure aluminum alloy at different strain rates (s^-1) – 0, 0.025, 0.1, and 0.3. In summary, it was observed that under the optimized ECAP conditions, specifically at a strain rate of 0.025 s^-1, the ultimate tensile strength increased by approximately 266%, micro-hardness by about 210%, and electrical resistivity by roughly 250% compared to the base material. The maximum value of the ultimate tensile strength was equal to 93 MPa, while the maximum value of hardness was equal to 41 VNN, and the maximum value of electrical resistivity was equal to 1.8 Ω.m, which is equivalent to the ratios mentioned above. Additionally, there was notable fragmentation of course second-phase particles and microstructure refinement

The Effect of Strain Rate on Electrical and Mechanical Characteristics of Pure Aluminum Using Equal Channel Angular Pressing (ECAP)

-During equal-channel angular pressing (ECAP), the effect of severe plastic deformation (SPD) rate on both the electrical (electrical resistance, denoted as (R),Ω and The electrical resistivity denoted as (ρ), Ω.m) and mechanical characteristics (Ultimate Tensile Strength abbreviated as (UTS), MPa and Micro-Hardness measured in Vickers Hardness Number, abbreviated as VHN) of pure aluminum alloy are experimentally investigated.ECAP was used to improve the pure aluminum alloy\u27s microstructure at room temperature, which had samples with square cross sections. The findings indicate that as the rate of strain decreases from 0.3 to 0.1 s^-1, there is a gradual increase in both Ultimate Tensile Strength (UTS) and hardness, with the highest values observed at a strain rate of 0.025 s^-1.This study empirically explored the influence of ECAP on the macrostructure, microstructure, mechanical properties, and electrical properties of pure aluminum alloy at different strain rates (s^-1) – 0, 0.025, 0.1, and 0.3. In summary, it was observed that under the optimized ECAP conditions, specifically at a strain rate of 0.025 s^-1, the ultimate tensile strength increased by approximately 266%, micro-hardness by about 210%, and electrical resistivity by roughly 250% compared to the base material. The maximum value of the ultimate tensile strength was equal to 93 MPa, while the maximum value of hardness was equal to 41 VNN, and the maximum value of electrical resistivity was equal to 1.8 Ω.m, which is equivalent to the ratios mentioned above. Additionally, there was notable fragmentation of course second-phase particles and microstructure refinement

Dephasing time of disordered two-dimensional electron gas in modulated magnetic fields

The dephasing time of disordered two-dimensional electron gas in a modulated magnetic field is studied. It is shown that in the weak inhomogeneity limit, the dephasing rate is proportional to the field amplitude, while in strong inhomogeneity limit the dependence is quadratic. It is demonstrated that the origin of the dependence of dephasing time on field amplitude lies in the nature of corresponding single-particle motion. A semiclassical Monte Carlo algorithm is developed to study the dephasing time, which is of qualitative nature but efficient in uncovering the dependence of dephasing time on field amplitude for arbitrarily complicated magnetic-field modulation. Computer simulations support analytical results. The crossover from linear to quadratic dependence is then generalized to the situation with magnetic field modulated periodically in one direction with zero mean, and it is argued that this crossover can be expected for a large class of modulated magnetic fields.Comment: 8 pages, 2 figure

Rainfall-induced hydraulic properties for unsaturated soil in Klang valley

Klang Valley area is one of the most landslide-prone areas in Malaysia, especially at Hulu Kelang, Kuala Lumpur. The area has been frequently hit by landslide since 1990s. Soil instability is agreed by researchers occurred due to high precipitation and long duration of rainfall which cause property damage and leading to injury and fatality. Slope failure is also triggered by the antecedent rainfall leads to infiltration of rainwater into soil. Therefore, study of rainwater infiltration is vital to relates soil – water interaction and soil behaviour for varies of rainfall intensities and duration for unsaturated soil. The objective of this paper is to determine and compare soil water characteristic curve (SWCC) which is one of the soil hydraulic parameters for Klang Valley area. Samples were collected to determine the soil hydraulic properties at Hulu Kelang area, Universiti Kebangsaan Malaysia (UKM) and Universiti Pertahanan Nasional Malaysia (UPNM) campuses. SWCC was obtained by pressure plate extractor apparatus experiment and the analysis was performed using Van Genuchten equation. Result of parameters obtained shows significant differences of soil at Hulu Kelang area compared to soils at UKM and UPNM campuses. This research is relevant to supports national slope master plan 2009-2023

Self-similarity and novel sample-length-dependence of conductance in quasiperiodic lateral magnetic superlattices

We study the transport of electrons in a Fibonacci magnetic superlattice produced on a two-dimensional electron gas modulated by parallel magnetic field stripes arranged in a Fibonacci sequence. Both the transmission coefficient and conductance exhibit self-similarity and the six-circle property. The presence of extended states yields a finite conductivity at infinite length, that may be detected as an abrupt change in the conductance as the Fermi energy is varied, much as a metal-insulator transition. This is a unique feature of transport in this new kind of structure, arising from its inherent two-dimensional nature.Comment: 9 pages, 5 figures, revtex, important revisions made. to be published in Phys. Rev.

CP violation in chargino decays in the MSSM

In the minimal supersymmetric standard model (MSSM) with complex parameters, supersymmetric loop effects can lead to \emph{CP} violation. We calculate the rate asymmetries of decays of charginos into the lightest neutralino and a $W$ boson on the basis of the most important loop contributions in the third generation squark sectors. It turns out that the \emph{CP} violating asymmetries can be a few per cent in typical regions of the parameter space of the MSSM. These processes would provide very promising channels for probing \emph{CP} violation in the MSSM at future high-energy colliders.Comment: 15 pages, 5 figures, LaTeX2

Tunable Lyapunov exponent in inverse magnetic billiards

The stability properties of the classical trajectories of charged particles are investigated in a two dimensional stadium-shaped inverse magnetic domain, where the magnetic field is zero inside the stadium domain and constant outside. In the case of infinite magnetic field the dynamics of the system is the same as in the Bunimovich billiard, i.e., ergodic and mixing. However, for weaker magnetic fields the phase space becomes mixed and the chaotic part gradually shrinks. The numerical measurements of the Lyapunov exponent (performed with a novel method) and the integrable/chaotic phase space volume ratio show that both quantities can be smoothly tuned by varying the external magnetic field. A possible experimental realization of the arrangement is also discussed.Comment: 4 pages, 6 figure

Electronic structure of nuclear-spin-polarization-induced quantum dots

We study a system in which electrons in a two-dimensional electron gas are confined by a nonhomogeneous nuclear spin polarization. The system consists of a heterostructure that has non-zero nuclei spins. We show that in this system electrons can be confined into a dot region through a local nuclear spin polarization. The nuclear-spin-polarization-induced quantum dot has interesting properties indicating that electron energy levels are time-dependent because of the nuclear spin relaxation and diffusion processes. Electron confining potential is a solution of diffusion equation with relaxation. Experimental investigations of the time-dependence of electron energy levels will result in more information about nuclear spin interactions in solids