Indirect cyclopexy for treatment of a chronic traumatic cyclodialysis cleft with hypotony

Cyclodialysis cleft is a rare clinical finding and therefore, reports on surgical repair techniques in the literature are limited. Additionally, hypotony can make repair technically challenging. We share a novel, simple surgical approach to management of a case of chronic traumatic cyclodialysis cleft with a successful outcome

Energy transfer in nonlinear network models of proteins

We investigate how nonlinearity and topological disorder affect the energy relaxation of local kicks in coarse-grained network models of proteins. We find that nonlinearity promotes long-range, coherent transfer of substantial energy to specific, functional sites, while depressing transfer to generic locations. Remarkably, transfer can be mediated by the self-localization of discrete breathers at distant locations from the kick, acting as efficient energy-accumulating centers.Comment: 4 pages, 3 figure

Electron Quasiparticles Drive the Superconductor-to-Insulator Transition in Homogeneously Disordered Thin Films

Transport data on Bi, MoGe, and PbBi/Ge homogeneously-disordered thin films demonstrate that the critical resistivity, $R_c$, at the nominal insulator-superconductor transition is linearly proportional to the normal sheet resistance, $R_N$. In addition, the critical magnetic field scales linearly with the superconducting energy gap and is well-approximated by $H_{c2}$. Because $R_N$ is determined at high temperatures and $H_{c2}$ is the pair-breaking field, the two immediate consequences are: 1) electron-quasiparticles populate the insulating side of the transition and 2) standard phase-only models are incapable of describing the destruction of the superconducting state. As gapless electronic excitations populate the insulating state, the universality class is no longer the 3D XY model. The lack of a unique critical resistance in homogeneously disordered films can be understood in this context. In light of the recent experiments which observe an intervening metallic state separating the insulator from the superconductor in homogeneously disordered MoGe thin films, we argue that the two transitions that accompany the destruction of superconductivity are 1) superconductor to Bose metal in which phase coherence is lost and 2) Bose metal to localized electron insulator via pair-breaking.Comment: This article is included in the Festschrift for Prof. Michael Pollak on occasion of his 75th birthda

Compliance error compensation in robotic-based milling

The paper deals with the problem of compliance errors compensation in robotic-based milling. Contrary to previous works that assume that the forces/torques generated by the manufacturing process are constant, the interaction between the milling tool and the workpiece is modeled in details. It takes into account the tool geometry, the number of teeth, the feed rate, the spindle rotation speed and the properties of the material to be processed. Due to high level of the disturbing forces/torques, the developed compensation technique is based on the non-linear stiffness model that allows us to modify the target trajectory taking into account nonlinearities and to avoid the chattering effect. Illustrative example is presented that deals with robotic-based milling of aluminum alloy

An inhomogeneous Josephson phase in thin-film and High-Tc superconductors

In many cases inhomogeneities are known to exist near the metal (or superconductor)-insulator transition, as follows from well-known domain-wall arguments. If the conducting regions are large enough (i.e. when the T=0 superconducting gap is much larger than the single-electron level spacing), and if they have superconducting correlations, it becomes energetically favorable for the system to go into a Josephson-coupled zero-resistance state before (i.e. at higher resistance than) becoming a "real" metal. We show that this is plausible by a simple comparison of the relevant coupling constants. For small grains in the above sense, the electronic grain structure is washed out by delocalization and thus becomes irrelevant. When the proposed "Josephson state" is quenched by a magnetic field, an insulating, rather then a metallic, state should appear. This has been shown to be consistent with the existing data on oxide materials as well as ultra-thin films. We discuss the Uemura correlations versus the Homes law, and derive the former for the large-grain Josephson array (inhomogenous superconductor) model. The small-grain case behaves like a dirty homogenous metal. It should obey the Homes law provided that the system is in the dirty supeconductivity limit. A speculation why that is typically the case for d-wave superconductors is presented.Comment: Conference proceeding for "Fluctuations in Superconductors" held in Nazareth, Israel in June, 2007; 6 pages with 1 figure, to appear in Physica

3D virtual worlds as environments for literacy learning

Background: Although much has been written about the ways in which new technology might transform educational practice, particularly in the area of literacy learning, there is relatively little empirical work that explores the possibilities and problems - or even what such a transformation might look like in the classroom. 3D virtual worlds offer a range of opportunities for children to use digital literacies in school, and suggest one way in which we might explore changing literacy practices in a playful, yet meaningful context. Purpose: This paper identifies some of the key issues that emerged in designing and implementing virtual world work in a small number of primary schools in the UK. It examines the tensions between different discourses about literacy and literacy learning and shows how these were played out by teachers and pupils in classroom settings.Sources of evidence: Case study data are used as a basis for exploring and illustrating key aspects of design and implementation. The case study material includes views from a number of perspectives including classroom observations, chatlogs, in-world avatar interviews with teachers and also pupils, as well as the author’s field notes of the planning process with accompanying minutes and meeting documents.Main argument: From a Foucauldian perspective, the article suggests that social control of pedagogical practice through the regulation of curriculum time, the normalisation of teaching routines and the regimes of individual assessment restricts teachers’ and pupils’ conceptions of what constitutes literacy. The counternarrative, found in recent work in new litearcies (Lankshear & Knobel, 2006) provides an attractive alternative, but a movement in this direction requires a fundamental shift of emphasis and a re-conceptualisation of what counts as learning.Conclusions: This work on 3D virtual worlds questions the notion of how transformative practice can be achieved with the use of new technologies. It suggests that changes in teacher preparation, continuing professional development as well as wider educational reform may be needed

Household flow detection using FEAT (flow estimating accelerometer-thermometer) device

This is the final version. Available from Elsevier via the DOI in this record. Data availability: The authors do not have permission to share data.The use of IoT devices in water end use disaggregation verification is an emerging field which offers benefits over conventional approaches, in terms of cost, accuracy and scalability. Having reliably disaggregated water appliance consumption data will enable smart water meter data to be used in household water conservation approaches and for understanding water consumption behaviours. The FEAT device provides a low cost, easily applied and scalable solution that is demonstrated to work even for very low flow conditions of 0.03 l/s. The FEAT device is a combination of a battery, Wi-fi board and MPU6050 sensors providing multi-modal accelerometer and thermometer data. The study places 7 of these FEAT devices onto hot and cold water pipes leading to a shower, which is operated 4 times in a high flow situation, 0.13 l/s, and 4 times in a low flow situation, 0.03 l/s. The data is then analysed and compared with a flow logger to determine if the FEAT device can detect when a domestic appliance is using water. There are limiting cases where the level of noise or external interference limits distorts the data, obscuring the distinguishable peaks in the data due to the similarity of the values. By using high and low pass filtering methods it was possible to enhance the peaks but there are still situations where peaks cannot be detected: for example, if a rigid pipe is not able to vibrate easily or if a hot water boiler is not triggered due to the low flow rate. However, the results show it should be possible to overcome these limiting cases, as it is much less likely for both the vibration and temperature data to be adversely affected by noise or external influences simultaneously, therefore decreasing the effect of noise and external influences. In conclusion, this research paper demonstrates that FEAT devices are a low cost, easily applied and scalable solution for detecting flow. By using high and low pass filtering, placing sensors on freely moving pipes and through the use of multi-modal verification, the FEAT device is shown to work on both metal and plastic pipes even in the lowest flow situations of 0.03 l/s. Therefore the FEAT device is a suitable solution for appliance identification in disaggregation verification datasets.Engineering and Physical Sciences Research Counci

A knowledge-guided active model method of skull segmentation on T1-weighted MR images

Skull is the anatomic landmark for patient set up of head radiation therapy. Skull is generally segmented from CT images because CT provides better definition of skull than MR imaging. In the mean time, radiation therapy is planned on MR images for soft tissue information. This study utilized a knowledge-guided active model (KAM) method to segmented skull on MR images in order to enable radiation therapy planning with MR images as the primary planning dataset. KAM utilized age-specific skull mesh models that segmented from CT images using a conditional region growing algorithm. Skull models were transformed to given MR images using an affine registration algorithm based on normalized mutual information. The transformed mesh models actively located skull boundaries by minimizing their total energy. The preliminary validation was performed on MR and CT images from five patients. The KAM segmented skulls were compared with those segmented from CT images. The average image similarity (kappa index) was 0.57. The initial validation showed that it was promising to segment skulls directly on MR images using KAM

Self-Reported Occupational Exposure to HIV and Factors Influencing its Management Practice: A Study of Healthcare Workers in Tumbi and Dodoma Hospitals, Tanzania.

Blood borne infectious agents such as hepatitis B virus (HBV), hepatitis C virus (HCV) and human immune deficiency virus (HIV) constitute a major occupational hazard for healthcare workers (HCWs). To some degree it is inevitable that HCWs sustain injuries from sharp objects such as needles, scalpels and splintered bone during execution of their duties. However, in Tanzania, there is little or no information on factors that influence the practice of managing occupational exposure to HIV by HCWs. This study was conducted to determine the prevalence of self-reported occupational exposure to HIV among HCWs and explore factors that influence the practice of managing occupational exposure to HIV by HCWs in Tanzania. Self-administered questionnaire was designed to gather information of healthcare workers' occupational exposures in the past 12 months and circumstances in which these injuries occurred. Practice of managing occupational exposure was assessed by the following questions: Nearly half of the HCWs had experienced at least one occupational injury in the past 12 months. Though most of the occupational exposures to HIV were experienced by female nurses, non-medical hospital staff received PEP more frequently than nurses and doctors. Doctors and nurses frequently encountered occupational injuries in surgery room and labor room respectively. HCWs with knowledge on the possibility of HIV transmission and those who knew whom to contact in event of occupational exposure to HIV were less likely to have poor practice of managing occupational exposure. Needle stick injuries and splashes are common among HCWs at Tumbi and Dodoma hospitals. Knowledge of the risk of HIV transmission due to occupational exposure and knowing whom to contact in event of exposure predicted practice of managing the exposure. Thus provision of health education on occupational exposure may strengthen healthcare workers' practices to manage occupational exposure

In-situ electronic characterization of graphene nanoconstrictions fabricated in a transmission electron microscope

We report electronic measurements on high-quality graphene nanoconstrictions (GNCs) fabricated in a transmission electron microscope (TEM), and the first measurements on GNC conductance with an accurate measurement of constriction width down to 1 nm. To create the GNCs, freely-suspended graphene ribbons were fabricated using few-layer graphene grown by chemical vapor deposition. The ribbons were loaded into the TEM, and a current-annealing procedure was used to clean the material and improve its electronic characteristics. The TEM beam was then used to sculpt GNCs to a series of desired widths in the range 1 - 700 nm; after each sculpting step, the sample was imaged by TEM and its electronic properties measured in-situ. GNC conductance was found to be remarkably high, comparable to that of exfoliated graphene samples of similar size. The GNC conductance varied with width approximately as, where w is the constriction width in nanometers. GNCs support current densities greater than 120 \muA/nm2, two orders of magnitude higher than has been previously reported for graphene nanoribbons and 2000 times higher than copper.Comment: 17 pages, 4 figures. Accepted by Nano Letter