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Small Number (small + number)
Kinds of Small Number Selected AbstractsPower of the Rank Adjacency Statistic to Detect Spatial Clustering in a Small Number of RegionsGEOGRAPHICAL ANALYSIS, Issue 1 2001John Paul Ekwaru The rank adjacency statistic D is a statistical method for assessing spatial autocorrelation or clustering of geographical data. It was originally proposed for summarizing the geographical patterns of cancer data in Scotland (IARC 1985). In this paper, we investigate the power of the rank adjacency statistic to detect spatial clustering when a small number of regions is involved. The investigations were carried out using Monte Carlo simulations, which involved generating patterned/clustered values and computing the power with which the D statistic would detect it. To investigate the effects of region shapes, structure of the regions, and definition of weights, simulations were carried out using two different region shapes, binary and nonhinary weights, and three different lattice structures. The results indicate that in the typical example of considering Canadian total mortality at the electoral district level, the D statistic had adequate power to detect general spatial autocorrelation in twenty-five or more regions. There was an inverse relationship between power and the level of connectedness of the regions, which depends on the weighting function, shape, and arrangement of the regions. The power of the D statistic was also found to compare favorably with that of Moran's I statistic. [source] Laws of Small Numbers: Extremes and Rare Events, 2nd revised and extended edition edited by M. Falk, J. Huesler, and R.-D.BIOMETRICS, Issue 3 2007Reiss No abstract is available for this article. [source] Ectopic germline cells in embryos of Xenopus laevisDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 7 2007Kohji Ikenishi Whether all descendants of germline founder cells inheriting the germ plasm can migrate correctly to the genital ridges and differentiate into primordial germ cells (PGCs) at tadpole stage has not been elucidated in Xenopus. We investigated precisely the location of descendant cells, presumptive primordial germ cells (pPGCs) and PGCs, in embryos at stages 23,48 by whole-mount in situ hybridization with the antisense probe for Xpat RNA specific to pPGCs and whole-mount immunostaining with the 2L-13 antibody specific to Xenopus Vasa protein in PGCs. Small numbers of pPGCs and PGCs, which were positively stained with the probe and the antibody, respectively, were observed in ectopic locations in a significant number of embryos at those stages. A few of the ectopic PGCs in tadpoles at stages 44,47 were positive in TdT-mediated dUTP digoxigenin nick end labeling (TUNEL) staining. By contrast, pPGCs in the embryos until stage 40, irrespective of their location and PGCs in the genital ridges of the tadpoles at stages 43,48 were negative in TUNEL staining. Therefore, it is evident that a portion of the descendants of germline founder cells cannot migrate correctly to the genital ridges, and that a few ectopic PGCs are eliminated by apoptosis or necrosis at tadpole stages. [source] Predation by seals on salmonids in two Scottish estuariesFISHERIES MANAGEMENT & ECOLOGY, Issue 3 2001T. J. Carter Detailed observations of the behaviour of harbour seals, Phoca vitulina L., at sites within the estuaries of the Rivers Dee and Don, in north-eastern Scotland, were made over two full years between 1993 and 1996. Small numbers of grey seals, Halichoerus grypus Fab., were also present. The presence of seals within the estuaries was strongly related to season, with maximum numbers observed in winter and early spring; seals were virtually absent in June and July. The River Don was used largely as a haul-out site, while the River Dee was used predominantly as a foraging site, although it was not possible to determine whether the same seals were using the two estuaries. More seals were hauled-out on the River Don during twilight and dark than in daylight. The seals were observed to eat mostly salmonids, Salmo salar L. and S. trutta L., unidentified roundfish and flounder, Pleuronectes flesus L. The otoliths identified in scats collected at the mouth of the River Don belonged to marine species indicating that the seals were also feeding outside the estuaries. A minimum estimate is given of the numbers of large salmonids eaten in each river during the course of the year. Although no information was available on the numbers of salmonids using the rivers or the reproductive status of the fish eaten by the seals, as a cause of mortality, seal predation on large salmonids in estuaries is apparently an order of magnitude less important than mortality caused by angling within the river. [source] Immunohistochemical staining for calretinin is useful in the diagnosis of ovarian sex cord,stromal tumoursHISTOPATHOLOGY, Issue 5 2001W G McCluggage Immunohistochemical staining for calretinin is useful in the diagnosis of ovarian sex cord,stromal tumours Aims:,Ovarian sex cord,stromal tumours are a heterogeneous group of neoplasms which may be confused morphologically with a wide variety of tumours. Calretinin positivity has previously been demonstrated in a small number of ovarian sex cord,stromal tumours. The aim of this study was to investigate calretinin staining in a series of these tumours and their histological mimics in order to determine the value of calretinin staining in a diagnostic setting. Methods and results:,Seventy-two neoplasms, including 37 ovarian sex cord,stromal tumours and 35 miscellaneous neoplasms which may enter into the differential diagnosis, were stained with a commercially available polyclonal antibody against calretinin. All sex cord,stromal tumours exhibited positivity except for a single fibrothecoma. In this group of tumours staining was generally diffuse and strong. Small numbers of the miscellaneous group of neoplasms exhibited positivity but this tended to be focal and weak, although this was not always the case. There was consistent strong positive staining of granulosa cells in follicular cysts and corpora lutea. There was also positive staining of luteinized stromal cells in two cases of ovarian stromal hyperplasia and hyperthecosis. Conclusions:,Calretinin is a sensitive immunohistochemical marker of ovarian sex cord,stromal tumours and may be useful in a diagnostic setting. However, the value is somewhat limited since occasional neoplasms which enter into the morphological differential diagnosis may be positive. Be that as it may, calretinin positivity may be of value in the diagnosis of an ovarian sex cord,stromal tumour and its differentiation from other neoplasms. In this regard, calretinin should always be used as part of a larger panel. [source] A systematic review of multivitamin and multimineral supplementation for infectionJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2006A. I. Stephen Abstract Background, Infections are major causes of morbidity and mortality worldwide. Micronutrients have important functions in the body's immune system. This systematic review examined the evidence from randomized controlled trials (RCTs) on whether multivitamin and multimineral supplementation is effective in reducing infection. Methods, Electronic databases searched: Cochrane Controlled Trials Register, EMBASE, MEDLINE, BIOSIS, CAB abstracts. Hand searching of nutrition journals and reference lists was carried out. RCTs and quasi-randomized trials of supplementation of adults with at least two vitamins or minerals or a combination were selected. Study results were combined in meta-analysis plots where appropriate. Results, Twenty studies were included in the review. Small numbers were available for each meta-analysis. Results are presented here without the Chandra group studies. No significant difference was found in the number of episodes of infection in older people (,65 years) between those supplemented and those not supplemented; (WMD) 0.06 [95% confidence interval (CI) ,0.04, 0.16], P = 0.25. In other adults groups, there were significantly less episodes of infection in those supplemented; (WMD) ,1.20 (95% CI ,2.08, ,0.32), P = 0.008. There was no significant difference between those older people supplemented and those not supplemented in the number with at least one infection; relative risk (RR) 0.98 (95% CI 0.86, 1.11), P = 0.77. Similarly, there was no significant difference in the numbers in other adult groups who had at least one episode of infection between those supplemented and those taking placebo; (RR) 0.81 (95% CI 0.65, 1.00), P = 0.06. Subgroup analyses suggested that supplemented people aged 65 years or over may benefit more if they are undernourished and supplemented for over 6 months, WMD ,0.67 infections (95% CI ,1.24, ,0.10), P = 0.02. Conclusion, Further large trials are needed, particularly in undernourished older people. Trials of supplementation periods of over 6 months are recommended. [source] Differential expression of catecholamine biosynthetic enzymes in the rat ventrolateral medullaTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2001Jacqueline K. Phillips Abstract Adrenergic (C1) neurons located in the rostral ventrolateral medulla are considered a key component in the control of arterial blood pressure. Classically, C1 cells have been identified by their immunoreactivity for the catecholamine biosynthetic enzymes tyrosine hydroxylase (TH) and/or phenylethanolamine N-methyltransferase (PNMT). However, no studies have simultaneously demonstrated the expression of aromatic L-amino acid decarboxylase (AADC) and dopamine ,-hydroxylase (DBH) in these neurons. We examined the expression and colocalization of all four enzymes in the rat ventrolateral medulla using immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Retrograde tracer injected into thoracic spinal segments T2,T4 was used to identify bulbospinal neurons. Using fluorescence and confocal microscopy, most cells of the C1 group were shown to be double or triple labeled with TH, DBH, and PNMT, whereas only 65,78% were immunoreactive for AADC. Cells that lacked detectable immunoreactivity for AADC were located in the rostral C1 region, and approximately 50% were spinally projecting. Some cells in this area lacked DBH immunoreactivity (6.5,8.3%) but were positive for TH and/or PNMT. Small numbers of cells were immunoreactive for only one of the four enzymes. Numerous fibres that were immunoreactive for DBH but not for TH or PNMT were noted in the rostral C1 region. Single-cell RT-PCR analysis conducted on spinally projecting C1 neurons indicated that only 76.5% of cells that contained mRNA for TH, DBH, and PNMT contained detectable message for AADC. These experiments suggest that a proportion of C1 cells may not express all of the enzymes necessary for adrenaline synthesis. J. Comp. Neurol. 432:20,34, 2001. © 2001 Wiley-Liss, Inc. [source] ENDOVASCULAR REPAIR OF POPLITEAL ARTERY ANEURYSMS: TECHNIQUES, CURRENT EVIDENCE AND RECENT EXPERIENCEANZ JOURNAL OF SURGERY, Issue 6 2006Ray Siauw Endovascular repair of popliteal artery aneurysms is a new technique, which has emerged as an alternative to open surgical bypass. However, evidence to support its use is limited. We present a review of current literature relevant to this technique. The MEDLINE search terms were popliteal artery, aneurysm, endovascular, endoluminal and stent. Fifty-eight articles were yielded, of which 21 were studies of endovascular repair by implantation of stent or stent graft of true aneurysms of the popliteal artery. There was only one randomized study. Small numbers of endovascular interventions are reported, with variations in study design and endovascular techniques. Long-term follow-up data is lacking; however, early results have been promising with high rates of initial treatment success. Early thrombosis of stent grafts occurs in approximately 10%, but this does not herald limb loss. Endovascular treatment offers potential benefits over traditional surgery, but needs to be studied further with a large-scale multicentre randomized trial. [source] Keratoprosthesis surgery: Eastern European and Russian devicesACTA OPHTHALMOLOGICA, Issue 2009ZF ZAGORSKI Purpose To present the development and current status of keratoprosthesis surgery in Eastern Europe. Methods Collection of data from coauthors and other surgeons involved in k-pro surgery. Results Large numbers of surgeries were performed in Filatov's Institute in Odessa (Ukraine), where over 1000 different types of devices developed by Puchkovskaya, Yakimienko and Golubenko were imlanted since 1966. The last model, s.c. "universal separable device" was implanted in over 750 with the best results (extrusion occured in about 2.5% cases). K-pro devices in Russia were mostly developed by S. Fyodorov Z. Moroz, V. Zuyev, ?. Krasnov, V. Volkov, R. Gundorova, N. Ushakov and V. Bedilo. Over 1500 surgeries sine 1969 resulted in the visual aquity improvement in 94% of cases. Haptics were made of titanium, stainless steel and also biocompatible materials (xenopericardium). In Poland about 100 surgeries were performed using mostly Russian and Ukrainian devices. The results were less favorable than in countries of origin. Small numbers were also implanted in other East European states. Conclusion In former Soviet Union keratoprosthesis surgery was well developed in selected centers (Moscow, Odessa). Surgeons in these places have gained extraordinary experience performing hundredes of surgeries. The results presented by the authors were excellent, however they were less favorable in the hands of surgeons from other countries. [source] Gradient-based Interpolation and Sampling for Real-time Rendering of Inhomogeneous, Single-scattering MediaCOMPUTER GRAPHICS FORUM, Issue 7 2008Zhong Ren Abstract We present a real-time rendering algorithm for inhomogeneous, single scattering media, where all-frequency shading effects such as glows, light shafts, and volumetric shadows can all be captured. The algorithm first computes source radiance at a small number of sample points in the medium, then interpolates these values at other points in the volume using a gradient-based scheme that is efficiently applied by sample splatting. The sample points are dynamically determined based on a recursive sample splitting procedure that adapts the number and locations of sample points for accurate and efficient reproduction of shading variations in the medium. The entire pipeline can be easily implemented on the GPU to achieve real-time performance for dynamic lighting and scenes. Rendering results of our method are shown to be comparable to those from ray tracing. [source] Lazy Solid Texture SynthesisCOMPUTER GRAPHICS FORUM, Issue 4 2008Yue Dong Abstract Existing solid texture synthesis algorithms generate a full volume of color content from a set of 2D example images. We introduce a new algorithm with the unique ability to restrict synthesis to a subset of the voxels, while enforcing spatial determinism. This is especially useful when texturing objects, since only a thick layer around the surface needs to be synthesized. A major difficulty lies in reducing the dependency chain of neighborhood matching, so that each voxel only depends on a small number of other voxels. Our key idea is to synthesize a volume from a set of pre-computed 3D candidates, each being a triple of interleaved 2D neighborhoods. We present an efficient algorithm to carefully select in a pre-process only those candidates forming consistent triples. This significantly reduces the search space during subsequent synthesis. The result is a new parallel, spatially deterministic solid texture synthesis algorithm which runs efficiently on the GPU. Our approach generates high resolution solid textures on surfaces within seconds. Memory usage and synthesis time only depend on the output textured surface area. The GPU implementation of our method rapidly synthesizes new textures for the surfaces appearing when interactively breaking or cutting objects. [source] Pose Controlled Physically Based MotionCOMPUTER GRAPHICS FORUM, Issue 4 2006Raanan Fattal Abstract In this paper we describe a new method for generating and controlling physically-based motion of complex articulated characters. Our goal is to create motion from scratch, where the animator provides a small amount of input and gets in return a highly detailed and physically plausible motion. Our method relieves the animator from the burden of enforcing physical plausibility, but at the same time provides full control over the internal DOFs of the articulated character via a familiar interface. Control over the global DOFs is also provided by supporting kinematic constraints. Unconstrained portions of the motion are generated in real time, since the character is driven by joint torques generated by simple feedback controllers. Although kinematic constraints are satisfied using an iterative search (shooting), this process is typically inexpensive, since it only adjusts a few DOFs at a few time instances. The low expense of the optimization, combined with the ability to generate unconstrained motions in real time yields an efficient and practical tool, which is particularly attractive for high inertia motions with a relatively small number of kinematic constraints. [source] DRIVE,Dispatching Requests Indirectly through Virtual EnvironmentCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 4 2010Hyung Won Choi Abstract Dispatching a large number of dynamically changing requests directly to a small number of servers exposes the disparity between the requests and the machines. In this paper, we present a novel approach that dispatches requests to servers through virtual machines, called Dispatching Requests Indirectly through Virtual Environment (DRIVE). Client requests are first dispatched to virtual machines that are subsequently dispatched to actual physical machines. This buffering of requests helps to reduce the complexity involved in dispatching a large number of requests to a small number of machines. To demonstrate the effectiveness of the DRIVE framework, we set up an experimental environment consisting of a PC cluster and four benchmark suites. With the experimental results, we demonstrate that the use of virtual machines indeed abstracts away the client requests and hence helps to improve the overall performance of a dynamically changing computing environment. Copyright © 2009 John Wiley & Sons, Ltd. [source] Concepts for computer center power managementCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2010A. DiRienzo Abstract Electrical power usage contributes significantly to the operational costs of large computer systems. At the Hypersonic Missile Technology Research and Operations Center (HMT-ROC) our system usage patterns provide a significant opportunity to reduce operating costs since there are a small number of dedicated users. The relatively predictable nature of our usage patterns allows for the scheduling of computational resource availability. We take advantage of this predictability to shut down systems during periods of low usage to reduce power consumption. With interconnected computer cluster systems, reducing the number of online nodes is more than a simple matter of throwing the power switch on a portion of the cluster. The paper discusses these issues and an approach for power reduction strategies for a computational system with a heterogeneous system mix that includes a large (1560-node) Apple Xserve PowerPC supercluster. In practice, the average load on computer systems may be much less than the peak load although the infrastructure supporting the operation of large computer systems in a computer or data center must still be designed with the peak loads in mind. Given that a significant portion of the time, systems loads can be less than full peak, an opportunity exists for cost savings if idle systems can be dynamically throttled back, slept, or shut off entirely. The paper describes two separate strategies that meet the requirements for both power conservation and system availability at HMT-ROC. The first approach, for legacy systems, is not much more than a brute force approach to power management which we call Time-Driven System Management (TDSM). The second approach, which we call Dynamic-Loading System Management (DLSM), is applicable to more current systems with ,Wake-on-LAN' capability and takes a more granular approach to the management of system resources. The paper details the rule sets that we have developed and implemented in the two approaches to system power management and discusses some results with these approaches. Copyright © 2009 John Wiley & Sons, Ltd. [source] A dynamic admission control scheme to manage contention on shared computing resourcesCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 2 2009Percival Xavier Abstract A virtual organization is established when physical organizations collaborate to share their computing resources with the aim of serving each other when there is a likelihood of insufficient local resources during peak resource usage periods at any organization. Contention becomes a potential problem when a large number of requests, which can overwhelm the aggregate capacity of shared resources, are submitted from the participating organizations coincidentally at the same period. In particular, when a small number of requests that require large amounts of computing resources are admitted in place of a large number of requests that require less computing resources, the overall system performance, in terms of admission ratio, can deteriorate significantly. Hence, admission control is necessary to reduce resource oversubscription. Because domain-shared computing resources are likely to be combined to form a large-scale system, it is not possible to define a fixed admission policy solely based on the request's CPU and execution time requirements. In this paper, we introduce an admission control framework, based on a pricing model, for a multi-domain-shared computing infrastructure. The performance of the admission control framework is evaluated under different scenarios that contribute to the overall degree of competition for shared resources. The results are presented and analyzed in this paper. Copyright © 2008 John Wiley & Sons, Ltd. [source] Distributed end-host multicast algorithms for the Knowledge GridCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2007Wanqing Tu Abstract The Knowledge Grid built on top of the peer-to-peer (P2P) network has been studied to implement scalable, available and sematic-based querying. In order to improve the efficiency and scalability of querying, this paper studies the problem of multicasting queries in the Knowledge Grid. An m -dimensional irregular mesh is a popular overlay topology of P2P networks. We present a set of novel distributed algorithms on top of an m -dimensional irregular mesh overlay for the short delay and low network resource consumption end-host multicast services. Our end-host multicast fully utilizes the advantages of an m -dimensional mesh to construct a two-layer architecture. Compared to previous approaches, the novelty and contribution here are: (1) cluster formation that partitions the group members into clusters in the lower layer where cluster consists of a small number of members; (2) cluster core selection that searches a core with the minimum sum of overlay hops to all other cluster members for each cluster; (3) weighted shortest path tree construction that guarantees the minimum number of shortest paths to be occupied by the multicast traffic; (4) distributed multicast routing that directs the multicast messages to be efficiently distributed along the two-layer multicast architecture in parallel, without a global control; the routing scheme enables the packets to be transmitted to the remote end hosts within short delays through some common shortest paths; and (5) multicast path maintenance that restores the normal communication once the membership alteration appears. Simulation results show that our end-host multicast can distributively achieve a shorter delay and lower network resource consumption multicast services as compared with some well-known end-host multicast systems. Copyright © 2006 John Wiley & Sons, Ltd. [source] Severe personality disorder emerging in childhood: a proposal for a new developmental disorderCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 1 2004Eileen Vizard Background The concept of ,severe personality disorder' is currently applied to adults with a history of serious antisocial and offending behaviour. There is, however, no similar classification that can be applied to the sub-group of children and adolescents who display persistent and serious offending from an early age. This omission from diagnostic nomenclature prevents the appropriate early identification, assessment and management of these young people. Method This paper therefore proposes a new developmental disorder: ,severe personality disorder emerging in childhood'. The existing evidence base strongly supports the presence of a developmental trajectory from childhood to adult life for the small number of children who show early signs of severe personality disorder (SPD). Based on a review of the literature and the experience of working in a specialist, forensic Child and Adolescent Mental Health Service (CAMHS), a multi-factorial model is proposed that outlines the developmental trajectory of SPD. This model includes neurobiological, psychosocial, environmental and systemic factors, within a developmental framework, and contributes to a more developmentally appropriate understanding of the genesis of severe personality disorder. Copyright © 2004 Whurr Publishers Ltd. [source] SOCIAL DISORGANIZATION OUTSIDE THE METROPOLIS: AN ANALYSIS OF RURAL YOUTH VIOLENCE,CRIMINOLOGY, Issue 1 2000D. WAYNE OSGOOD In order to extend the study of community social disorganization and crime beyond its exclusive focus on large urban centers, we present an analysis of structural correlates of arrest rates for juvenile violence in 264 nonmetropolitan counties of four states. Findings support the generality of social disorganization theory: Juvenile violence was associated with rates of residential instability, family disruption, and ethnic heterogeneity. Though rates of poverty were not related to juvenile violence, this is also in accord with social disorganization theory because, unlike urban settings, poverty was negatively related to residential instability. Rates of juvenile violence varied markedly with population size through a curvilinear relationship in which counties with the smallest juvenile populations had exceptionally low arrest rates. Analyses used negative binomial regression (a variation of Poisson regression) because the small number of arrests in many counties meant that arrest rates would be ill suited to least-squares regression. [source] VIOLENCE AMONG ADOLESCENTS LIVING IN PUBLIC HOUSING: A TWO-SITE ANALYSIS,CRIMINOLOGY AND PUBLIC POLICY, Issue 1 2003TIMOTHY O. IRELAND Research Summary: Current knowledge about violence among public housing residents is extremely limited. Much of what we know about violence in and around public housing is derived from analysis of Uniform Crime Report (UCR) data or victimization surveys of public housing residents. The results of these studies suggest that fear of crime among public housing residents is high and that violent offense rates may be higher in areas that contain public housing compared with similar areas without public housing. Yet, "[r]ecorded crime rates (and victimization rates) are an index not of the rate of participation in crime by residents of an area, but of the rate of crime (or victimization) that occurs in an area whether committed by residents or non-residents" (Weatherburn et al., 1999:259). Therefore, neither UCR nor victimization data measurement strategies address whether crime in and around public housing emanates from those who reside in public housing. Additionally, much of this research focuses on atypical public housing,large developments with high-rise buildings located in major metropolitan areas. To complement the existing literature, we compare rates of self-reported crime and violence among adolescents who reside in public housing in Rochester, N.Y., and Pittsburgh, Pa., with adolescents from the same cities who do not live in public housing. In Rochester, property crime and violence participation rates during adolescence and early adulthood among those in public housing are statistically equivalent to participation rates among those not in public housing. In Pittsburgh, living in public housing during late adolescence and early adulthood, particularly in large housing developments,increases the risk for violent offending, but not for property offending. The current study relies on a relatively small number of subjects in public housing at any single point in time and is based on cross-sectional analyses. Even so, there are several important policy implications that can be derived from this study, given that it moves down a path heretofore largely unexplored. Policy Implications: If replicated, our findings indicate that not all public housing is inhabited disproportionately by those involved in crime; that to develop appropriate responses, it is essential to discover if the perpetrators of violence are residents or trespassers; that policy should target reducing violence specifically and not crime in general; that a modification to housing allocation policies that limits, to the extent possible, placing families with children in late adolescence into large developments might reduce violence perpetrated by residents; that limited resources directed at reducing violence among residents should be targeted at those developments or buildings that actually have high rates of participation in violence among the residents; and that best practices may be derived from developments where violence is not a problem. [source] Comparison of bone marrow and peripheral blood ZAP-70 status examined by flow cytometric immunophenotyping in patients with chronic lymphocytic leukemiaCYTOMETRY, Issue 4 2006Rachel Sheridan Abstract Background: The mutational status of the immunoglobulin heavy chain variable gene in patients with chronic lymphocytic leukemia correlates with prognosis. Patients with mutated IgVH genes fare better than those with unmutated genes. Gene expression profiling studies identified the tyrosine kinase ZAP-70 to be expressed in unmutated CLL samples. Flow cytometric examination of ZAP-70 expression in tumor cells has been proposed to be a convenient surrogate marker for IgVH mutational status. However, a few studies have shown a small number of discordant results between ZAP-70 positivity, IgVH mutational status, and clinical outcome. There have been no reported studies comparing bone marrow samples with peripheral blood for ZAP-70 expression in CLL patients. Methods: We searched our flow cytometry files from October 2004 through April 2006 and identified CLL in 311 bone marrow and peripheral blood specimens from 256 patients. We defined ZAP-70 positivity as greater than 30% of the CD19+ B-cells above the isotype control value that coexpress ZAP-70. Statistical analyses were performed using the Fisher exact test and student t -test. Results: A significantly greater number of bone marrow specimens were positive for ZAP-70 when compared with the number of peripheral blood specimens. Of all the ZAP-70 negative specimens, CLL cells from bone marrow had a greater mean percentage of ZAP-70 positive cells when compared with the CLL cells from peripheral blood. Finally, six patients were identified who were ZAP-70 positive in the bone marrow but ZAP-70 negative in the peripheral blood. Conclusions: These results may be due to either an increase in the false positive rate in bone marrow specimens or to an intrinsic feature of CLL cells in the compartment that is biologically distinct from peripheral tumor cells. As prognosis and treatment decisions may be based on ZAP-70 results from either specimen type, it is prudent to further examine this observation. © 2006 International Society for Analytical Cytology [source] CD87 as a marker for terminal granulocytic maturation: Assessment of its expression during granulopoiesisCYTOMETRY, Issue 1 2003M. Tarek Elghetany Abstract Background Understanding the normal surface maturation pattern of granulocytes is essential for the recognition of abnormal patterns, which in turn may be of diagnostic or pathogenetic significance in disorders such as myelodysplastic syndromes and inherited bone marrow failure disorders. CD87 plays a role in cellular interaction, cell migration, and inflammatory response. Surface expression of this antigen has not been adequately studied on bone marrow granulocytes, and the small number of previous studies has provided conflicting data. Methods Bone marrow aspirates from 11 control subjects were studied by flow cytometry and a lysed whole blood technique to compare surface expression of CD87 on marrow granulocytes with those of CD11b, CD16, CD35, and CD10, which are expressed at the myelocyte, metamyelocyte, band, and segmented stage of neutrophilic development, respectively. Four sorting experiments of CD87+ granulocytes were also performed. Results Our study showed no statistical difference between surface expression of CD35 and CD87 (P > 0.3), whereas significant differences existed between CD87 and the other antibodies (P < 0.004). Sorting experiments showed that more than 80% of CD87+ cells were bands and segmented neutrophils. Dual staining for CD87 and CD35 showed that most CD87+ granulocytes coexpress CD35. Conclusions CD87 is expressed on granulocytes at the band and segmented neutrophil stage of development and can be used to study normal and abnormal granulopoiesis. Cytometry Part B (Clin. Cytometry) 51B:9,13, 2003. © 2002 Wiley-Liss, Inc. [source] Constraint-induced movement therapy (CIMT): Pediatric applicationsDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2009Kathleen Brady Abstract The purpose of this article is to describe theoretical and research bases for constraint-induced movement therapy (CIMT), to discuss key features and variations in protocols currently in use with children, and to review the results of studies of efficacy. CIMT has been found to be an effective intervention for increasing functional use of the hemiparetic upper extremity in adults with chronic disability from stroke. CIMT developed out of behavioral research on the phenomenon of "learned nonuse" of an upper extremity, commonly observed following sensory and/or motor CNS injury, in which failure to regain use persists even after a period of partial recovery. CIMT includes three key elements: (1) constraining the use of the less-impaired upper extremity (UE); (2) intensive, repetitive daily therapist-directed practice of motor movements with the impaired UE for an extended period (2,3 weeks); and (3) shaping of more complex action patterns through a process of rewarding successive approximations to the target action. Mechanisms responsible for success are thought to be separate but complementary, that is, operant conditioning (reversal of learned nonuse) and experience-driven cortical reorganization. CIMT has recently been extended to children with hemiparesis secondary to perinatal stroke or other CNS pathology. Numerous case studies, as well as a small number of randomized controlled or controlled clinical trials have reported substantial gains in functional use of the hemiplegic UE following CIMT with children. Protocols vary widely in terms of type of constraint used, intensity and duration of training, and outcome measures. In general, all report gains in functional use, with minimal or no adverse effects. Continued research is needed, to clarify optimal protocol parameters and to further understand mechanisms of efficacy. © 2009 Wiley-Liss, Inc. Dev Disabil Res Rev 2009;15:102,111. [source] Genetic basis of rett syndromeDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 2 2002Ignatia B. Van den Veyver Abstract The origin of Rett syndrome has long been debated, but several observations have suggested an X-linked dominant inheritance pattern. We and others have pursued an exclusion-mapping strategy using DNA from a small number of familial Rett syndrome cases. This work resulted in the narrowing of the region likely to harbor the mutated gene to Xq27.3-Xqter. After systematic exclusion of several candidate genes, we discovered mutations in MECP2, the gene that encodes the transcriptional repressor, methyl-CpG-binding protein 2. Since then, nonsense, missense, or frameshift mutations have been found in at least 80% of girls affected with classic Rett syndrome. Sixty-four percent of mutations are recurrent C > T transitions at eight CpG dinucleotides mutation hotspots, while the C-terminal region of the gene is prone to recurrent multinucleotide deletions (11%). Most mutations are predicted to result in total or partial loss of function of MeCP2. There is no clear correlation between the type and position of the mutation and the phenotypic features of classic and variant Rett syndrome patients, and XCI appears to be a major determinant of phenotypic severity. Further research focuses on the pathogenic consequences of these mutations along the hypothesis of loss of transcriptional repression of a small number of genes that are essential for neuronal function in the maturing brain. MRDD Research Reviews 2002;8:82,86. © 2002 Wiley-Liss, Inc. [source] Churchill and Sip1a repress fibroblast growth factor signaling during zebrafish somitogenesisDEVELOPMENTAL DYNAMICS, Issue 2 2010Fatma O. Kok Abstract Cell-type specific regulation of a small number of growth factor signal transduction pathways generates diverse developmental outcomes. The zinc finger protein Churchill (ChCh) is a key effector of fibroblast growth factor (FGF) signaling during gastrulation. ChCh is largely thought to act by inducing expression of the multifunctional Sip1 (Smad Interacting Protein 1). We investigated the function of ChCh and Sip1a during zebrafish somitogenesis. Knockdown of ChCh or Sip1a results in misshapen somites that are short and narrow. As in wild-type embryos, cycling gene expression occurs in the developing somites in ChCh and Sip1a compromised embryos, but expression of her1 and her7 is maintained in formed somites. In addition, tail bud fgf8 expression is expanded anteriorly in these embryos. Finally, we found that blocking FGF8 restores somite morphology in ChCh and Sip1a compromised embryos. These results demonstrate a novel role for ChCh and Sip1a in repression of FGF activity. Developmental Dynamics 239:548,558, 2010. © 2009 Wiley-Liss, Inc. [source] Probability of walking, wheeled mobility, and assisted mobility in children and adolescents with cerebral palsyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2010ROBERT J PALISANO Aim, Our aim was to describe how the probability of walking, wheeled mobility, and assisted mobility changes with environmental setting and age in children and adolescents with cerebral palsy (CP). Method, The parents of a population-based sample of 642 children and adolescents (360 males, 282 females; age range 16mo,21y) reported their children's mobility at home, school, and outdoors at 6- or 12-month intervals a mean of 5.2 times. Generalized mixed-effects analyses were used to model the probabilities. Results, By age 3 years, children with motor function classified as level I according to the Gross Motor Function Classification System (GMFCS) walked in all three settings. Children/adolescents classified as level V used assisted mobility, with a small number using wheeled mobility. In the case of children classified as GMFCS level II, the probability of walking varied with the environmental setting, which, at age 18, is outdoors 90% of the time. Among children classified as GMFCS level III, the probability of walking was highest at age 9 at school (68%), and at age 18 was approximately 50% in all three settings. Among children/adolescents rated as GMFCS level IV, the probability of wheeled mobility increased with age and, at age 18, 57% of mobility took place outdoors. Interpretation, The results provide evidence that age and environmental setting influence method of mobility of children/adolescents with CP. The method that is preferred in one setting may not be preferred in another setting or at another age. [source] Chairperson and Faculty Gender in Academic Emergency Medicine DepartmentsACADEMIC EMERGENCY MEDICINE, Issue 8 2006David Cheng MD Objectives: Despite the influx of female physicians in academic medicine departments, there are a small number of women in faculty and departmental leadership positions in emergency medicine (EM). The objective of this study was to determine if the gender of the chairperson of an academic EM department is associated with the gender of the residency program director (RPD) and gender proportion of its faculty. Methods: This was a retrospective analysis of 133 academic EM departments using the Society for Academic Emergency Medicine online residency catalog, program Web site, or e-mail. Main outcome measures were proportion of female EM faculty and gender of the RPD. Results: Data were available for 133 academic departments. Women chaired 7.5% (n= 10) of departments and comprised 22.3% of all faculty and 15.0% (n= 20) of RPD positions. EM departments that were chaired by women had a significantly higher percentage of female faculty compared with those led by men (31% vs. 22%; p = 0.01). Similarly, departments that were chaired by women had a significantly higher proportion of female RPDs compared with those chaired by men (50% vs. 12%; p < 0.01). Compared with departments chaired by men, the RPD was 5.0 times (95% confidence interval = 1.9 to 27.8; p < 0.01) more likely to be a woman if the chairperson was also a woman. Conclusions: An academic EM department was more likely to have a higher proportion of female faculty and a female RPD when the department chairperson was female. [source] Deletion of 8p: a report of a child with normal intelligenceDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 12 2001Linda Gilmore PhD The case is presented of a female infant with a distal deletion of 8p (8p23.1,pter) whose development was monitored over a 5-year period from 12 months of age. Although previous literature has suggested that 8p deletion is associated with mild to moderate intellectual disability, the child reported here has normal intelligence. Despite initial delays in gross motor and language skills, cognitive development (assessed with the Bayley Scales of Infant Development) and intellectual ability (measured on the Stanford-Binet Intelligence Scale) were within average range. It is argued that the small number of previous case reports may have created a misleading impression of intellectual development in individuals with distal deletions of 8p. [source] Self-help treatments for disorders of recurrent binge eating: a systematic reviewACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2006S. C. Stefano Objective:, To evaluate self-help interventions for patients with binge eating disorder (BED) and bulimia nervosa (BN), tested in randomized controlled trials, and compared with waiting list or any other type of control group. Methods:, A systematic review including quality appraisal was conducted of randomized controlled trials, using self-help techniques in patients with BED and/or BN. Six databases were searched during the period between January 1994 and June 2004. Results:, A total of 2686 articles were identified, 1701 abstracts were evaluated in detail and, nine studies fulfilled the inclusion criteria for this review. All studies indicated that patients treated with active interventions had a reduced number of binge eating episodes at end of treatment. Conclusion:, The results support self-help interventions but shall be interpreted with caution. Because of the small number of studies using self-help techniques for BED and BN, further larger randomized, multi-center controlled studies that apply standardized inclusion criteria, evaluation instruments and self-help materials, are needed. [source] Cell-type-specific limitation on in vivo serotonin storage following ectopic expression of the Drosophila serotonin transporter, dSERTDEVELOPMENTAL NEUROBIOLOGY, Issue 5 2006Sang Ki Park Abstract The synaptic machinery for neurotransmitter storage is cell-type specific. Although most elements of biosynthesis and transport have been identified, it remains unclear whether additional factors may be required to maintain this specificity. The Drosophila serotonin transporter (dSERT) is normally expressed exclusively in serotonin (5-HT) neurons in the CNS. Here we examine the effects of ectopic transcriptional expression of dSERT in the Drosophila larval CNS. We find a surprising limitation on 5-HT storage following ectopic expression of dSERT and green fluorescence protein-tagged dSERT (GFP-dSERT). When dSERT transcription is driven ectopically in the CNS, 5-HT is detectable only in 5-HT, dopamine (DA), and a very limited number of additional neurons. Addition of exogenous 5-HT does not dramatically broaden neuronal storage sites, so this limitation is only partly due to restricted intercellular diffusion of 5-HT. Furthermore, this limitation is not due to gross mislocalization of dSERT, because cells lacking or containing 5-HT show similar levels and subcellular distribution of GFP-dSERT protein, nor is it due to lack of the vesicular transporter, dVMAT. These data suggest that a small number of neurons selectively express factor(s) required for 5-HT storage, and potentially for function of dSERT. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006 [source] What Is the mechanism of SIDS?DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2009Clues from epidemiology Abstract The cause of sudden infant death syndrome (SIDS) is unknown. Many mechanisms have been postulated, although thermal stress, rebreathing of expired gases and infection/inflammation seem the most viable hypotheses for the causation of SIDS. Deaths from SIDS have reduced dramatically following the recommendation not to place infants to sleep prone. Epidemiological data have shown that prone sleeping position is more risky in winter, colder latitudes, higher altitudes, if the infant is unwell or has excessive bedding or clothing. This suggests prone sleeping position involves either directly or indirectly a thermal mechanism. SIDS caused by an infective/inflammatory mechanism might be associated with deaths occurring during the night. Rebreathing of expired gases, airway obstruction, long QT syndrome and other genetic conditions may explain a small number of sudden unexpected deaths in infancy. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 215,222, 2009 [source] | |||||||||||||||||||||||||||||||||||||||||||||||||