Trachomatous Trichiasis: Surgical Management and Impact

Background: Trachomatous trichiasis (TT), is the in-turning of eyelashes from long-term, progressive conjunctival scarring initiated by chlamydia trachomatis. It is the painful blinding stage of trachoma. We aimed to measure impact of TT on Quality of Life (QoL) and household poverty; identify the most effective of two commonly used surgical TT procedures; and measure impact of TT surgery on QoL and daily living. Methods: A randomized, controlled, single-masked clinical trial was conducted in Ethiopia comparing the bilamellar tarsal rotation (BLTR) and posterior lamellar tarsal rotation (PLTR) procedures (1000-participants). A case-control study was nested within the trial to measure QoL using standard quantitative tools, and household poverty using three economic measures (assetbased analysis, self-rated and peer-rated wealth) among TT cases and compared to healthy neighborhood controls (200-participants). These participants were followed-up after one year to measure impact of TT surgery on QoL and daily living using the same tools. Results: PLTR was the superior surgical procedure, with only 13% recurrent TT by 12-months compared to 22% in the BLTR (OR=1.96; 95%CI:1.40–2.75; p=0.0001). At baseline, TT cases were more likely to belong to poorer households with substantially lower QoL, less likely to participate in, more likely to report difficulty and assistance in performing productive and leisure activities regardless of visual impairment than controls. Twelve months after surgery, QoL scores of TT cases and their ability to perform daily activities without difficulty and assistance improved substantially, independent of the presence of visual acuity improvement. Conclusions: PLTR surgery appears to be superior in terms of reduced recurrence and complications for the programmatic management of TT. TT is associated with household poverty and is disabling and substantially reduces QOL. Corrective surgery improves QoL and functional capabilities of affected individuals even without vision gains and may contribute to improved household income and wealth

Extension of dynamic source routing protocol in mobile ad hoc network

In a large dynamic network, data can be copied anywhere to make it fault tolerant and easy accessed but there must be an efficient protocol to manage the replicas and make sure the data is consistent and high in availability with a low communication cost. In this paper, we introduced a new protocol, named Diagonal Replication in Mesh (DRM) for data replica control protocol for a large dynamic network by using quorum and voting techniques to improve the availability and the communication cost because quorum techniques reduce the number of copies involved in reading or writing data.The protocol of DRM replicates data for large dynamic network by putting the protocol in a logical mesh structure and access consistent data by ensuring the quorum not to have a nonempty intersection quorum.To evaluate our protocol, we developed a simulation model in Java.Our results proved that DRM improves the performance of the response time compare to Three Dimensional Grid structure Protocol (TDGS)

NE102A Plastic Scintillator Response to He-3 Ions

Plastic scintillators are widely used in detecting nuclear radiation due to their low construction cost, the ability to be produced in nearly any shape and size and relatively fast time response, among which NE102A (or its equivalents, BC400 and EJ-212) is one of the most famous and widely used scintillators in the focal plane of the particle magnetic spectrometers. In this study, the response of a large NE102A scintillator to He-3 ions was investigated in the energy range of 55-87 MeV. The experimental data were collected from the measurements carried out at the accelerator center of University of Groningen, the Netherlands (KVI-CART). The results of this research, acceptably consistent with previous published experimental data, confirmed that the response of the NE102A scintillator to He-3 ions with energies more than 10 MeV is approximately linear

Staff Knowledge, Adherence to Infection Control Recommendations and Seroconversion Rates in Hemodialysis Centers in Khartoum

Introduction: We evaluated hemodialysis (HD) staff knowledge, adherence to infection control recommendations and seroconversion rates for hepatitis B virus (HBV) and hepatitis C virus (HCV) in 13 centers that continuously provided HD services in Khartoum State between June 2009 and November 2010. Methods: The knowledge of 182 HD staff members was evaluated by a self-filled questionnaire. Relevant data were obtained from 1011 HD patients by direct interviews and record review. Adherence of staff members to infection control recommendations was evaluated by direct observation. Results: HD staff members achieved a median score of 81% in knowledge evaluation (range 44-100%). Better scores were achieved by more experienced staff. We identified serious gaps in knowledge related to the environmental risk of viral transmission. Regular screening by enzyme-linked immunoassay (ELISA) was performed in 46% of centers. Only half susceptible patients were vaccinated against HBV. Staff dedicated for treatment of HBV positive patients were found in only 57% of centers that served such patients. Hand washing recommendations were strictly observed in 15% of centers, disinfection of HD stations between patients was strictly observed in 23% of centers, medications were prepared in a separate area in 8% of centers and delivered separately to each patient in none of the centers. There were 2.5 HCV seroconversions and 0.6 HBV seroconversions per 100 patient-years. Center characteristics that predicted HCV seroconversion were accommodation of HCV-positive patients in the same center, using ELISA for patient screening, and assigning more than 3 patients for one HD nurse. Conclusion: There are serious gaps in HD staff knowledge and adherence to infection control recommendations. A structured training program for HD staff members is urgently required. Keywords: Hemodialysis; HBV; HCV; Infection Control; Khartou

Spin-valve Josephson junctions with perpendicular magnetic anisotropy for cryogenic memory

We demonstrate a Josephson junction with a weak link containing two ferromagnets with perpendicular magnetic anisotropy and independent switching fields in which the critical current can be set by the mutual orientation of the two layers. Such pseudospin-valve Josephson junctions are a candidate cryogenic memory in an all superconducting computational scheme. Here, we use Pt/Co/Pt/CoB/Pt as the weak link of the junction with dCo=0.6 nm, dCoB=0.3 nm, and dPt=5 nm and obtain a 60% change in the critical current for the two magnetization configurations of the pseudospin-valve. Ferromagnets with perpendicular magnetic anisotropy have advantages over magnetization in-plane systems, which have been exclusively considered at this point, as, in principle, the magnetization and magnetic switching of layers in the junction should not affect the in-plane magnetic flux

Spin relaxation through Kondo scattering in Cu/Py lateral spin valves

The temperature dependence of the spin diffusion length typically reflects the scattering mechanism responsible for spin relaxation. Within nonmagnetic metals it is reasonable to expect the Elliot-Yafet mechanism to play a role and thus the temperature dependence of the spin diffusion length might be inversely proportional to resistivity. In lateral spin valves, measurements have found that at low temperatures the spin diffusion length unexpectedly decreases. By measuring the transport properties of lateral Py/Cu/Py spin valves, fabricated from Cu with magnetic impurities of <1 ppm and ∼4 ppm, we extract a spin diffusion length which shows this suppression below 30 K only in the presence of the Kondo effect. We have calculated the spin-relaxation rate and isolated the contribution from magnetic impurities. We find the spin-flip probability of a magnetic impurity to be 34%. Our analysis demonstrates the dominant role of Kondo scattering in spin relaxation, even in low concentrations of order 1 ppm, and hence illustrates its importance to the reduction in spin diffusion length observed by ourselves and others

Development time and new product sales: A contingency analysis of product innovativeness and price

Opposing theories and conflicting empirical results with regard to the effect of development time on new product sales suggest the need for a contingency analysis into factors affecting this relationship. This study uses a unique combination of accounting and perceptual data from 129 product development projects to test the combined contingency effect of product innovativeness and new product price on the relationship between development time and new product sales. The results show that for radically new products with short development times, price has no effect on new product sales. When the development time is long, price has a negative effect on the sales of radical new products. The findings additionally show that price has no effect on sales for incremental new products with short development times and a negative effect for incremental new products with long development times. Together, these findings shed new light on the relationship between development time and new product sales

Effects of structural ordering on infrared active vibrations within Bi₂(Te₍₁—ₓ₎Seₓ)₃

We performed a materials investigation into the properties of the THz conductivity spectra in the ternary alloy Bi₂(Te₍₁—ₓ₎Seₓ)₃ as a function of selenium fraction, x, and temperature. We find that the reduction in crystalline anharmonicity caused by the preferential ordering of the ₓ=1/3 phase of Bi₂(Te₍₁—ₓ₎Seₓ)₃ results in the prominent E1uphonon (occurring between 1.5 and 1.9 THz) red-shifting on cooling less than the binary Bi2Te3and Bi2Se3samples. We also find that the E1uphonon couples to an electronic continuum at low temperatures (T⩽40K), regardless of Bi₂(Te₍₁—ₓ₎Seₓ)₃stoichiometry or the Hall mobility of the topological insulator crystal. These results highlight the role that these optical modes play in the electronic and thermal transport within this ternary alloy and pave the way for exploring the interesting phonon dynamics within these topological insulator and thermoelectric materials

Laboratory comparison of aging characteristics of warm mix asphalts involving natural and synthetic water containing additives

When comparing the aging characteristics of hot and warm mix asphalts from a technical point of view, it can intuitively be expected that a warm mix asphalt would be less subjected to aging-induced failures due to lower application temperatures. Since the side effects of warm asphalt technology should be investigated distinctly. This study addresses the aging investigation of properties of bituminous mixtures containing two (i.e., natural and synthetic zeolite) water based additives available on the market. Within the scope of this study, short- and long-term aging conditions were simulated on mixtures containing various contents of additives as well as on control specimens. The aging indices were determined based on the hardness ratio employing indirect tensile strength values in order to investigate the aging induced failures betide by time. Aging indices showed that the specimens with water containing additives demonstrate relatively better resistance against hardening than conventional hot mix asphalt specimens