Distributed self-stabilizing placement of replicated resources in emerging networks

Emerging large scale distributed networking systems, such as P2P file sharing systems, sensor networks, and ad hoc wireless networks, require replication of content, functionality, or configuration to enact or optimize communication tasks. The placement of these replicated resources can significantly impact performance. We present a novel self-stabilizing, fully distributed, asynchronous, scalable protocol that can be used to place replicated resources such that each node is "close" to some copy of any object. We describe our protocol in the context of a graph with colored nodes, where a node's color indicates the replica/task that it is assigned. Our combination of theoretical results and simulation prove stabilization of the protocol, and evaluate its performance in the context of convergence time, message transmissions, and color distance. Our results show that the protocol generates colorings that are close to the optimal under a set of metrics, making such a protocol ideal for emerging networking systems.     

Memory in sub-clinical obsessive-compulsive checkers

In a series of experiments we extended the research on possible memory deficits in subclinical obsessive-compulsive Ss who reported excessive checking. Using a variety of memory tests we compared 20 subclinical checkers to 20 Ss without obsessive-compulsive symptomatology. Contrary to hypothesis, checkers remembered self-generated words better than read words just as much as did normals, but they were more likely than normals to report thinking they had studied words that, in fact, had not been on the study list. Further, they more often confused whether they read or generated the words at study. Checkers did not appear to perseverate on already-recalled words on repeated free recall tests any more than did normals. However, checkers remembered fewer actions overall and more often misremembered whether they had performed, observed, or written these actions. Such memory deficits may contribute to the development of excessive checking.     

CFD–DEM modelling of particle flow in IsaMills – Comparison between simulations and PEPT measurements

The IsaMill? is a high speed stirred mill with a horizontal configuration that offers advantages such as energy efficiency and an inert grinding environment. A combined computational fluid dynamics (CFD) and discrete element method (DEM) approach was developed to investigate the particle and fluid flows inside a simplified IsaMill?. The configuration of the mill was simpler than that of an actual IsaMill? and no feed flow or rotor was considered. The CFD–DEM model is a progression from earlier DEM only models of “dry” systems which did not account for the fluid phase. The properties of flows at a macroscopically steady state, such as velocity field, distributions of particle velocity and acceleration in the radial direction and power draw, were analysed. Detailed comparisons were carried out between the simulation results and Positron Emission Particle Tracking (PEPT) measurements under similar conditions. The comparisons showed reasonable agreements, confirming that both techniques can capture the key features of the flow. The discrepancies between simulated and measured results were discussed. The findings indicated that the proposed model can be used to generate microdynamic information that is useful in leading to a better understanding of the underpinning physics of flow inside mills.     

Association of MSX1 and TGFB3 with nonsyndromic clefting in humans

Nonsyndromic cleft lip with or without cleft palate (CL/P) and nonsyndromic cleft palate only (CPO) are common congenital anomalies with significant medical, psychological, social, and economic ramifications. Both CL/P and CPO are examples of complex genetic traits. There exists sufficient evidence to hypothesize that disease loci for CL/P and CPO can be identified by a candidate-gene linkage-disequilibrium (LD) strategy. Candidate genes for clefting, including TGFA, BCL3, DLX2, MSX1, and TGFB3, were screened for LD with either CL/P or CPO in a predominantly Caucasian population, with both case-control- and nuclear-family-based approaches. Previously reported LD for TGFA with both CL/P and CPO could not be confirmed, except in CL/P patients with a positive family history. Also, in contrast to previous studies, no LD was found between BCL3 and either CL/P or CPO. Significant LD was found between CL/P and both MSX1 and TGFB3 and between CPO and MSX1, suggesting that these genes are involved in the pathogenesis of clefting. In addition, a mutation search in the genes DLX2, MSX1, and TGFB3 was performed in 69 CPO patients and in a subset of the CL/P patients. No common mutations were found in the coding regions of these genes; however, several rare variants of MSX1 and TGFB3 were found that may alter the latters' normal function. These results form the basis for future research, including (a) mutation searches in the MSX1 and TGFB3 genes in Caucasian CL/P patients and (b) extension of the search for MSX1 mutations in CPO patients to the noncoding regions.     

A measure of teachers' observations of student behavior.

Describes the construction of the Rochester School Competency Schedule, a 26-item inventory derived by factor analysis to measure the ways in which teachers categorize students' behavior. 4 factors are involved, reflecting cognitive competence, social compliance, motivational orientation, and social competence. Test-retest reliability over 4 wks on a sample of 12 teachers was obtained using the final instrument; reliability coefficients for the 4 factors respectively were .80, .79, .71, and .75, with a coefficient for the total score of .85. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Variation in ovarian morphology in four species of New World moles with a peniform clitoris

Female moles of the Old World genus Talpa display a curious suite of reproductive features that include a peniform clitoris and ovaries with a discrete interstitial gland or testis-like region (so-called 'ovotestes'). The masculinization of the female external genitalia in Talpa has accordingly been linked with secretion of androgens from the interstitial gland region of the fetal gonad. Although their ovarian morphology has received less attention, some species of New World moles also have ovaries with a pronounced interstitial gland (for example star-nosed mole, Condylura cristata), whereas females of other species do not (for example eastern mole, Scalopus aquaticus). Although it is difficult to determine the sex of both Old and New World moles, published accounts describing the external genitalia of female moles are available only for Talpa. The hypothesis that masculinization of the female external genitalia in moles is associated with the presence of an ovarian interstitial gland (OIG) was tested in the present study by using a comparative approach to determine whether these features are ever found in isolation of one another. Three genera of North American moles (Scapanus, Condylura and Neurotrichus) were studied and a peniform clitoris was found in all three species, but OIG were found in only two of three genera. The ovaries of S. latimanus and S. orarius were unremarkable, with no evidence of a discrete interstitial gland or testis-like region. Mapping these results onto recent talpid phylogenies indicates that loss of the bipolar ovarian morphology is a derived trait in Scapanus, and conclusively demonstrates that masculinization of the external genitalia in female moles can develop in the presence or absence of 'ovotestes'.     

Tracking the motion of media particles inside an IsaMill™ using PEPT

Stirred milling is continually gaining acceptance in the mineral processing industry. The IsaMill? is a high intensity stirred mill with a horizontal configuration and internal classification. The present work describes the use of Positron Emission Particle Tracking (PEPT) to trace the motion of a media bead in a simplified IsaMill? rig. The rig has the same inner dimensions and disc sizes as the real M20 IsaMill? but is a closed unit without any flow through, no product separator and only three discs. The PEPT system has the advantage of being able to obtain detailed charge motion measurements in opaque and aggressive environments such as those encountered in grinding processes. Glass beads (3 mm) and ceramic media (3.5 mm) were tracked over a range of volumetric fillings and rotational speeds. An analysis of the resultant trajectory fields in terms of media location (occupancy), velocity, and acceleration is presented.     

Toward Optimal Network Fault Correction in Externally Managed Overlay Networks

We consider an end-to-end approach of inferring probabilistic data forwarding failures in an externally managed overlay network, where overlay nodes are independently operated by various administrative domains. Our optimization goal is to minimize the expected cost of correcting (i.e., diagnosing and repairing) all faulty overlay nodes that cannot properly deliver data. Instead of first checking the most likely faulty nodes as in conventional fault localization problems, we prove that an optimal strategy should start with checking one of the candidate nodes, which are identified based on a potential function that we develop. We propose several efficient heuristics for inferring the best node to be checked in large-scale networks. By extensive simulation, we show that we can infer the best node in at least 95 percent of time, and that first checking the candidate nodes rather than the most likely faulty nodes can decrease the checking cost of correcting all faulty nodes.     

Problems associated with the atrophic mandible

A range of treatment options has been presented regarding the use of dental implants to rehabilitate patients who otherwise have compromised function using conventional tissue-borne prostheses. This patient population offers significant challenges to both the surgeon and the prosthodontist. Generally speaking, IODs retained on two or more endosteal osseointegrated implants; transosteal, subperiosteal, ramus frame implant-supported and implant-retained prostheses, and a totally implant-supported design offer options to treat the severely atrophic mandible. When bone support or volume is so lacking that augmentation procedures are required, bone grafting can be considered as a treatment option. The state-of-the-art of implant treatment for the atrophic mandible offers to the dental professional and patient a variety of options. Thus far, it is too early to make specific recommendations as to which treatment offers the best option for each patient. It is fair to say that the ISP remains the gold standard against which other treatments can be compared.