Panel III: Implications of the New Telecommunications Legislation

We present a method that employs a tree-based Neural Network (NN) for performing classification. The novel mechanism, apart from incorporating the information provided by unlabeled and labeled instances, re-arranges the nodes of the tree as per the laws of Adaptive Data Structures (ADSs). Particularly, we investigate the Pattern Recognition (PR) capabilities of the Tree-Based Topology-Oriented SOM (TTOSOM) when Conditional Rotations (CONROT) [8] are incorporated into the learning scheme. The learning methodology inherits all the properties of the TTOSOM-based classifier designed in [4]. However, we now augment it with the property that frequently accessed nodes are moved closer to the root of the tree. Our experimental results show that on average, the classification capabilities of our proposed strategy are reasonably comparable to those obtained by some of the state-of-the-art classification schemes that only use labeled instances during the training phase. The experiments also show that improved levels of accuracy can be obtained by imposing trees with a larger number of nodes

The role of the lateral amygdala in the retrieval and maintenance of fear-memories formed by repeated probabilistic reinforcement

The lateral nucleus of the amygdala (LA) is a key element in the neural circuit subserving Pavlovian fear-conditioning, an animal model of fear and anxiety. Most studies have focused on the role of the LA in fear acquisition and extinction, i.e., how neural plasticity results from changing contingencies between a neutral conditioned stimulus (CS) (e.g., a tone) and an aversive unconditioned stimulus (US) (e.g., a shock). However, outside of the lab, fear-memories are often the result of repeated and unpredictable experiences. Examples include domestic violence, child abuse or combat. To better understand the role of the LA in the expression of fear resulting from repeated and uncertain reinforcement, rats experienced a 30% partial reinforcement (PR) fear-conditioning schedule four days a week for four weeks. Rats reached asymptotic levels of conditioned-fear expression after the first week. We then manipulated LA activity with drug (or vehicle) (VEH) infusions once a week, for the next three weeks, before the training session. LA infusions of muscimol (MUSC), a GABA-A agonist that inhibits neural activity, reduced CS evoked fear-behavior to pre-conditioning levels. LA infusions of pentagastrin (PENT), a cholecystokinin-2 (CCK) agonist that increases neural excitability, resulted in CS-evoked fear-behavior that continued past the offset of the CS. This suggests that neural activity in the LA is required for the retrieval of fear memories that stem from repeated and uncertain reinforcement, and that CCK signaling in the LA plays a role in the recovery from fear after the removal of the fear-evoking stimulus

Five New Species of Guimaraesiella (Phthiraptera: Ischnocera) from Broadbills (Aves: Passeriformes: Calyptomenidae: Eurylaimidae)

Under embargo until: 2020-11-15Five new species of Guimaraesiella Eichler, 1949 are described and illustrated from hosts in the Eurylaimidae and Calyptomenidae. They are Guimaraesiella corydoni n. sp. from Corydon sumatranus laoensisMeyer de Schauensee, 1929; Guimaraesiella latirostris n. sp. from Eurylaimus ochromalusRaffles, 1822; Guimaraesiella cyanophoba n. sp. from Cymbirhynchus macrorhynchus malaccensisSalvadori, 1874 and C. m. siamensisMeyer de Schauensee and Ripley, 1940; Guimaraesiella altunai n. sp. from Calyptomena viridis caudacutaSwainson, 1838; and Guimaraesiella forcipata n. sp. from Eurylaimus steerii steeriiSharpe, 1876. These represent the first species of Guimaraesiella described from the Calyptomenidae and Eurylaimidae, as well as the first species of this genus described from the Old World suboscines.acceptedVersio

Seasonal Pattern of Acute Myocardial Infarction in the National Registry of Myocardial Infarction

ObjectivesThe purpose of this study was to determine whether the rate of hospital admission for acute myocardial infarction (AMI) varies seasonally in a large, prospective U.S. registry.BackgroundIdentification of specific patterns in the timing of the onset of AMI is of importance because it implies that there are triggers external to the atherosclerotic plaque. Using death certificate data, most investigators have noted a seasonal pattern to the death rate from AMI. However, it is unclear whether this observation is due to variation in the prevalence of AMI or to other factors that may alter the likelihood of a fatal outcome.MethodsWe examined the seasonal mean number of cases of AMI (adjusted for the length of days in each season) that were submitted to the National Registry of Myocardial Infarction (NRMI) by 138 high volume core hospitals over a 3-year period (December 21,1990 through December 20,1993) during which the number of hospitals participating in the Registry was stable. Data were analyzed using general linear modeling and analysis of variance.ResultsHigh volume core hospitals reported 83,541 cases of AMI to the Registry during the study period. Approximately 10% more such cases were entered into the Registry in winter or spring than in summer (p < 0.05). The same trends were seen in both northern and southern states, men and women, patients <70 versus ≥70 years of age and those with Q wave versus non-Q wave AMI.ConclusionsWe conclude that there is a seasonal pattern to the reporting rate of cases of AMI in the NRMI. This observation further supports the hypothesis that acute cardiovascular events may be triggered by events that are external to the atherosclerotic plaque

Beta-Adrenergic Receptors in the Lateral Nucleus of the Amygdala Contribute to the Acquisition but Not the Consolidation of Auditory Fear Conditioning

Beta-adrenergic receptors (βARs) have long been associated with fear disorders and with learning and memory. However, the contribution of these receptors to Pavlovian fear conditioning, a leading behavioral model for studying fear learning and memory, is still poorly understood. The aim of this study was to investigate the involvement of βAR activation in the acquisition, consolidation and expression of fear conditioning. We focused on manipulations of βARs in the lateral nucleus of the amygdala (LA) because of the well-established contribution of this area to fear conditioning. Specifically, we tested the effects of intra-LA microinfusions of the βAR antagonist, propranolol, on learning and memory for auditory Pavlovian fear conditioning in rats. Pre-training propranolol infusions disrupted the initial acquisition, short-term memory (STM), and long-term memory (LTM) for fear conditioning, but infusions immediately after training had no effect. Further, infusion of propranolol prior to testing fear responses did not affect fear memory expression. These findings indicate that amygdala βARs are important for the acquisition but not the consolidation of fear conditioning

Impact of RNA Editing on Functions of the Serotonin 2C Receptor in vivo

Transcripts encoding 5-HT2C receptors are modified posttranscriptionally by RNA editing, generating up to 24 protein isoforms. In recombinant cells, the fully edited isoform, 5-HT2C-VGV, exhibits blunted G-protein coupling and reduced constitutive activity. The present studies examine the signal transduction properties of 5-HT2C-VGV receptors in brain to determine the in vivo consequences of altered editing. Using mice solely expressing the 5-HT2C-VGV receptor (VGV/Y), we demonstrate reduced G-protein coupling efficiency and high-affinity agonist binding of brain 5-HT2C-VGV receptors. However, enhanced behavioral sensitivity to a 5-HT2C receptor agonist was also seen in mice expressing 5-HT2C-VGV receptors, an unexpected finding given the blunted G-protein coupling. In addition, mice expressing 5-HT2C-VGV receptors had greater sensitivity to a 5-HT2C inverse agonist/antagonist enhancement of dopamine turnover relative to wild-type mice. These behavioral and biochemical results are most likely explained by increases in 5-HT2C receptor binding sites in the brains of mice solely expressing 5-HT2C-VGV receptors. We conclude that 5-HT2C-VGV receptor signaling in brain is blunted, but this deficiency is masked by a marked increase in 5-HT2C receptor binding site density in mice solely expressing the VGV isoform. These findings suggest that RNA editing may regulate the density of 5-HT2C receptor binding sites in brain. We further caution that the pattern of 5-HT2C receptor RNA isoforms may not reflect the pattern of protein isoforms, and hence the inferred overall function of the receptor

Cellular mechanisms of myocardial infarct expansion.

Infarct expansion is acute regional dilatation and thinning of the infarct zone. There are several possibilities for the mechanism of this alteration in cardiac shape: thinning could be caused by 1) cell rupture, 2) a reduction in the intercellular space, or 3) stretching of myocytes or 4) slippage of groups of myocytes so that less cells are distributed across the wall. To determine the relative contributions of these cellular mechanisms of wall thinning and dilatation, detailed study of transverse histological sections of rat hearts with infarct expansion was performed 1, 2, and 3 days after coronary ligation. The number of cells across the wall was determined in six regions within, adjacent to, and remote from the infarct. Cell counting was performed so that the total number of cells across the wall and the number of cells per unit length (cell density) across the wall were determined. The transmural cell count and the cell density were correlated with the wall thickness in each region. Myocyte cross-sectional areas and sarcomere lengths were also measured. The results from the infarct expansion hearts were compared with those of sham-operated control hearts that had been similarly analyzed. To ensure that mechanisms identified in the rat were applicable to human infarct expansion, five hearts from patients who died within 3 days of infarction and two hearts from patients without coronary disease wer

Assessment and optimisation of STCA performance: Using the Pareto optimal receiver operating characteristic

EUROCONTROL Annual Safety R&D Seminar (2008), Southampton, UK, 22-24 October 2008Short Term Conflict Alert (STCA) systems are complex software programs, with many parameters that must be adjusted to achieve best performance. We describe a simple evolutionary algorithm for optimising the trade-off between wanted alerts and nuisance alerts. The procedure yields an estimate of the Pareto optimal Receiver Operating Characteristic for the STCA system and we discuss additional uses of this for characterising and comparing the performance of STCA systems and airspaces

Pediatric pacemaker infections: Twenty years of experience

AbstractObjective: We sought to evaluate possible predictors of early and late pacemaker infections in children. Methods: A review was performed of all pacemakers implanted in children at The Children's Hospital of Philadelphia between 1982 and 2001. Infections were classified as superficial cellulitus, deep pacemaker pocket infection necessitating removal, or positive blood culture without an identifiable source. Results: A total of 385 pacemakers (224 epicardial and 161 endocardial) were implanted in 267 patients at 8.4 ± 6.2 years. All 2141 outpatient visits were reviewed (median follow-up, 29.4 months; range, 2-232 months). There were 30 (7.8%) pacemaker infections: 19 (4.9%) superficial infections; 9 (2.3%) pocket infections; and 2 (0.5%) isolated positive blood cultures. All superficial infections resolved with intravenous antibiotics. The median time from implantation to infection was 16 days (range, 2 days-5 years). Only 1 deep infection occurred after primary pacemaker implantation. Six patients with deep infections were pacemaker dependent and were successfully managed with intravenous antibiotics, followed by lead-generator removal and implantation of a new pacemaker in a remote location. In univariate analyses trisomy 21 (relative risk, 3.9; P <.01), pacemaker revisions (relative risk, 2.5; P <.01), and single-chamber devices (relative risk, 2.4; P <.05) were identified as predictors of infection. However, in multivariate analyses only trisomy 21 and pacemaker revisions were predictors. Conclusions: The incidences of superficial and deep pacemaker infections were 4.9% and 2.3%, respectively. Trisomy 21 and pacemaker revisions were significant risk factors in the development of infection after pacemaker implantation. For primary pacemaker implantation, the risk of infection requiring system removal is low (0.3%).J Thorac Cardiovasc Surg 2002;124:821-

Tidal Wave II, Community Colleges, and Student Financial Aid

Article examining the impact of "Tidal Wave II" (a bulge of high school graduates wanting access to higher education) on public community colleges for the five-year period from 2000-2001 to 2005-2006