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ZUSAMMENFASSUNGDie linksatriale Katheterablation ist eine etablierte rhythmuserhaltenden Behandlung bei Patienten mit Vorhofflimmern und anderen supraventikulären Rhythmusstörungen. Es verdichten sich Hinweise, dass eine rhythmuserhaltende Therapie zusätzlich zur Verbesserung der Lebensqualität und Linderung von vorhofflimmerassozierten Symptomen kardiovaskuläre Ereignisse wie etwa ischämische Schlaganfälle verhindern und zum Erhalt der kognitiven Funktion beitragen kann. Allerdings finden sich bei etwa einem Viertel der Patienten nach linksatrialer Vorhofflimmerablation mittels Kernspintomografie klinisch stumme akute zerebrale Ischämien und etwa 0,2–0,3 % aller abladierten Patienten erleiden periinterventionell eine zerebrale Ischämie mit manifesten neurologischen Defiziten. Eine optimale Antikoagulation zur Prävention thrombembolischer Ereignisse im Zuge einer linksatrialen Katheterablationen ist daher ein zentraler Bestandteil in einem ganzheitlichen Therapiekonzept. Im Rahmen des vorliegenden Artikels soll die Datenlage und insbesondere die Ergebnisse der vom AFNET koordinierten AXAFA-AFNET-5-Studie vorgestellt werden.

Eastern equine encephalitis virus (EEEV) causes a rare but severe disease in horses and humans, and is maintained in an enzootic transmission cycle between songbirds andCuliseta melanuramosquitoes. In 2019, the largest EEEV outbreak in the United States for more than 50 years occurred, centered in the Northeast. To explore the dynamics of the outbreak, we sequenced 80 isolates of EEEV and combined them with existing genomic data. We found that, like previous years, cases were driven by frequent short-lived virus introductions into the Northeast from Florida. Once in the Northeast, we found that Massachusetts was important for regional spread. We found no evidence of any changes in viral, human, or bird factors which would explain the increase in cases in 2019. By using detailed mosquito surveillance data collected by Massachusetts and Connecticut, however, we found that the abundance ofCs. melanurawas exceptionally high in 2019, as was the EEEV infection rate. We employed these mosquito data to build a negative binomial regression model and applied it to estimate early season risks of human or horse cases. We found that the month of first detection of EEEV in mosquito surveillance data and vector index (abundance multiplied by infection rate) were predictive of cases later in the season. We therefore highlight the importance of mosquito surveillance programs as an integral part of public health and disease control.

In July 2019, Bourbon virus RNA was detected in anAmblyomma americanumtick removed from a resident of Long Island, New York. Tick infection and white-tailed deer (Odocoileus virginianus) serosurvey results demonstrate active transmission in New York, especially Suffolk County, emphasizing a need for surveillance anywhereA. americanumis reported.

Europace : the European journal of pacing, arrhythmias and cardiac electrophysiology 24(6), 1037-1038 (2022). doi:10.1093/europace/euab317, Published by Oxford Univ. Press, Oxford

Intracranial calcifications (ICC) are the most common neuropathological finding in the brains of children exposed in utero to the Zika virus (ZIKV). Using a mouse model of developmental ZIKV infection, we reported widespread calcifications in the brains of susceptible mice that correlated in multiple ways with the behavioral deficits observed. Here, we examined the time course of ICC development and the role of iron deposition in this process, in 3 genetically distinct inbred strains of mice. Brain iron deposits were evident by Perls’ staining at 2 weeks post infection, becoming increasingly dense and coinciding with calcium buildup and the formation of ICCs. A regional analysis of the brains of susceptible mice (C57BL/6J and 129S1/SvImJ strains) revealed the presence of iron initially in regions containing many ZIKV-immunoreactive cells, but then spreading to regions containing few infected cells, most notably the thalamus and the fasciculus retroflexus. Microglial activation was widespread initially and later delineated the sites of ICC formation. Behavioral tests conducted at 5–6 weeks of age revealed greater deficits in mice with the most extensive iron deposition and calcification of subcortical regions, such as thalamus. These findings point to iron deposition as a key factor in the development of ICCs after developmental ZIKV infection.

We tested 700 serum samples collected throughout Panama from 2015 to 2016 for detecting antibodies and RNA of arboviruses. In convalescent specimens, microsphere immunoassay detected an antibody prevalence of 59.3% for dengue virus (DENV) and 30.3% for Zika virus (ZIKV), which included samples that were collected before the Panamanian surveillance system reported the first case of Zika in the country. For acute sera, the most common arbovirus was DENV with 18 positive samples (6%), followed by four (1.3%) of ZIKV and one (0.6%) of chikungunya virus (CHIKV). Our results indicate a change in the chronology of when ZIKV was first detected in Panama and stress the importance of integrating various approaches to enable improved surveillance of both endemic and emerging arboviruses.

Exposure of the developing fetus to Zika virus (ZIKV) results in a set of brain abnormalities described as the congenital Zika syndrome. Although microcephaly is the most obvious outcome, neuropathologies, such as intracranial calcifications and polymicrogyria, can occur in the absence of microcephaly. Moreover, the full impact of exposure on motor, social, and cognitive skills during development remains uncharacterized. We examined the long-term neurobehavioral consequences of neonatal ZIKV exposure in four genetically divergent inbred mouse strains (C57BL/6J, 129S1/SvImJ, FVB/NJ, and DBA/2J). Male and female mice were infected on postnatal day 1, considered comparable with exposure late in the second trimester of humans. We demonstrate strain differences in early susceptibility to the virus and the time course of glial reaction in the brain. These changes were associated with strain- and sex-dependent differences in long-term behavioral abnormalities that include hyperactivity, impulsiveness, and motor incoordination. In addition, the adult brains of susceptible mice exhibited widespread calcifications that may underlie the behavioral deficits observed. Characterization of the neuropathological sequelae of developmental exposure to the Zika virus in different immunocompetent mouse strains provides a foundation for identifying genetic and immune factors that contribute to long-term neurobehavioral consequences in susceptible individuals. SIGNIFICANCE STATEMENT Developmental Zika virus (ZIKV) infection is now known to cause brain abnormalities in infants that do not display microcephaly at birth, and the full impact of these more subtle neuropathologies has yet to be determined. We demonstrate in a mouse model that long-lasting behavioral aberrations occur after developmental ZIKV exposure. We compare four divergent mouse strains and find that the effects of Zika infection differ greatly between strains, in terms of behavioral changes, sex differences, and the intracranial calcifications that develop in the brains of susceptible mice. These findings provide a foundation for identifying susceptibility factors that lead to the development of abnormal behaviors secondary to ZIKV infection early in life.

Surveillance for the emerging infectious disease Eastern equine encephalitis, and its causative virus in mosquitoes, continued within New York State from 2013 to 2019. There were increases in geographic area and number of consecutive years, with cases in four mammalian species, and virus in 11 mosquito species. The first cases in a goat and in an emu were reported. The first detection of virus in Aedes cinereus was reported. Virus in phylogenetic group NY4 was isolated from a horse and from mosquitoes 6 kilometers and 13 days apart in 2013. Phylogenetic groups NY4 and NY5 were found 15 days apart in two towns 280 kilometers distant in 2013. Within four adjacent counties there was a pattern of overlap, where four had NY5, two adjacent counties had NY6, two adjacent counties had NY7, and one county had NY5, NY6, and NY7, reducible to a Euler diagram. Virus in phylogenetic group NY5, found within an 11-kilometer wide area in New York State, was related to FL4 found in Florida 1,398 kilometers distant. This was consistent with a phylogenetic group originating in Florida, then being moved to a specific location in New York State, by migratory birds in consecutive years 2013 and 2014.

Forest disturbance effects on La Crosse virus (LACV) are currently unknown. We determined the abundance of three LACV accessory vectors (Aedes albopictus, Ae. canadensis, and Ae. vexans) and the primary amplifying host (Eastern chipmunk, Tamias striatus), and tested for LACV prevalence in both vectors and chipmunks, across a gradient of experimental forest disturbance treatments in southwest Virginia. Forest disturbance significantly affected the abundance of LACV accessory vectors, with a higher abundance on disturbed sites for Ae. canadensis and Ae. vexans. However, there was no significant disturbance effect on chipmunk abundance. Forest disturbance significantly affected LACV prevalence in mosquito vectors, with most (80%) detections on unlogged control sites, which past work showed harbor the highest abundance of the two most common LACV vectors (the primary vector Aedes triseriatus, and Ae. japonicus). Interestingly, LACV nucleic acid was only detected in Ae. japonicus and Culex pipiens/restuans, with no detections in the primary vector, Ae. triseriatus. In contrast to the vector results, antibodies were only found in chipmunks on logged sites, but this result was not statistically significant. Overall, our results suggest that human LACV risk should generally decline with logging, and reveal the potential importance of accessory vectors in LACV maintenance in Appalachian forests.

Following its introduction into New York State (NYS) in 1999, West Nile virus (WNV; Flavivirus, Flaviviridae) underwent a rapid expansion throughout the USA and into Canada and Latin America. WNV has been characterized as being evolutionarily stable, with weak geographic structure, a dominance of purifying selection and limited adaptive change. We analyzed all available full-genome WNV sequences, focusing on the 543 available sequences from NYS, which included 495 newly sequenced 2000–15 isolates. In addition, we analyzed deep-sequencing data from 317 of these isolates. While our data are generally in agreement with the limited pace of evolutionary change and broad geographic and temporal mixing identified in other studies, we have identified some important exceptions. Most notably, there are 14 codons which demonstrated evidence of positive selection as determined by multiple models, including some positions with evidence of selection in NYS exclusively. Coincident with increased WNV activity, genotypes possessing one or more of these mutations, designated NY01, NY07, and NY10, have increased in prevalence in recent years and displaced historic strains. In addition, we have found a geographical bias with many of these mutations, which suggests selective pressures and adaptations could be regional. Lastly, our deep-sequencing data suggest both increased overall diversity in avian tissue isolates relative to mosquito isolates and multiple non-synonymous minority variants that are both host-specific and retained over time and space. Together, these data provide novel insight into the evolutionary pressures on WNV and the need for continued genetic surveillance and characterization of emergent strains.

In this retrospective causal comparative study, we analyzed 5 years of electronic medical records (EMR) data at two large teaching hospitals to determine effectiveness of evidence-based VTE prophylaxis physician order entry systems (CPOE) order sets, measured by acute VTE diagnosis, length of stay (LOS), and comorbidities outcomes. Results indicate lower VTE rate among non-surgical patients, while surgical patients did not benefit. Placing VTE orders via sets was not effective in influencing LOS and comorbidities outcomes. The study highlights the role of medical informatics in improving patient outcomes through reduction of variability in patient care practice.

Metastable $ϵ$-gallium oxide is expected to have very good properties for high-power electronics, combining the large band gap and high breakdown field of $\ensuremath{\beta}$-Ga${}_{2}$O${}_{3}$ with a very high spontaneous polarization. Unfortunately, synthesizing $ϵ$-Ga${}_{2}$O${}_{3}$ is quite tricky, yet the authors have managed it. Introducing tin avoids the formation of volatile suboxides, which leadsto a widened growth window in which $ϵ$-gallium oxide can beformed. Furthermore, the growth mechanism that the authors revealcould be relevant for the growth of any binary oxide.

Although early Homo is hypothesized to have used tools more than australopiths to process foods prior to consumption, it is unknown how much the food processing techniques they used altered the material properties of foods, and therefore the masticatory forces they generated, and how well they were able to comminute foods. This study presents experimental data on changes to food material properties caused by mechanical tenderization (pounding with a stone tool) and cooking (dry roasting) of two foods likely to have been important components of the hominin diet: meat and tubers. Mechanical tenderization significantly decreased tuber toughness by 42%, but had no effect on meat toughness. Roasting significantly decreased several material properties of tubers correlated with masticatory effort including toughness (49%), fracture stress (28%) and elastic modulus (45%), but increased the toughness (77%), fracture stress (50%–222%), and elastic modulus of muscle fibers in meat (308%). Despite increasing many material properties of meat associated with higher masticatory forces, roasting also decreased measured energy loss by 28%, which likely makes it easier to chew. These results suggest that the use of food processing techniques by early Homo probably differed for meat and tubers, but together would have reduced masticatory effort, helping to relax selection to maintain large, robust faces and large, thickly enameled teeth.

In the Western Hemisphere, Zika virus is thought to be transmitted primarily by Aedes aegypti mosquitoes. To determine the extent to which Ae. albopictus mosquitoes from the United States are capable of transmitting Zika virus and the influence of virus dose, virus strain, and mosquito species on vector competence, we evaluated multiple doses of representative Zika virus strains in Ae. aegypti and Ae. albopictus mosquitoes. Virus preparation (fresh vs. frozen) significantly affected virus infectivity in mosquitoes. We calculated 50% infectious doses to be 6.1-7.5 log 10 PFU/mL; minimum infective dose was 4.2 log 10 PFU/mL. Ae. albopictus mosquitoes were more susceptible to infection than Ae. aegypti mosquitoes, but transmission efficiency was higher for Ae. aegypti mosquitoes, indicating a transmission barrier in Ae. albopictus mosquitoes. Results suggest that, although Zika virus transmission is relatively inefficient overall and dependent on virus strain and mosquito species, Ae. albopictus mosquitoes could become major vectors in the Americas.

Maximum bite force affects craniofacial morphology and an organism's ability to break down foods with different material properties. Humans are generally believed to produce low bite forces and spend less time chewing compared with other apes because advances in mechanical and thermal food processing techniques alter food material properties in such a way as to reduce overall masticatory effort. However, when hominins began regularly consuming mechanically proc- essed or cooked diets is not known. Here, we apply a model for estimating maximum bite forces and stresses at the second molar in modern human, nonhuman pri- mate, and hominin skulls that incorporates skeletal data along with species-specific estimates of jaw muscle archi- tecture. The model, which reliably estimates bite forces, shows a significant relationship between second molar bite force and second molar area across species but does not confirm our hypothesis of isometry. Specimens in the genus Homo fall below the regression line describing the relationship between bite force and molar area for non- human anthropoids and australopiths. These results suggest that Homo species generate maximum bite forces below those predicted based on scaling among australopiths and nonhuman primates. Because this decline occurred before evidence for cooking, we hypothesize that selection for lower bite force production was likely made possible by an increased reliance on nonthermal food processing. However, given substantial variability among in vivo bite force magnitudes meas- ured in humans, environmental effects, especially varia- tions in food mechanical properties, may also be a factor. The results also suggest that australopiths had ape-like bite force capabilities. Am J Phys Anthropol 151:544- 557, 2013. V C 2013 Wiley Periodicals, Inc.

This chapter examines the current state-of-the-art multiplex PCR and diagnostic platforms that are based on multiplex PCR but contain additional features to enhance sensitivity, multiplexing capability, or ease of use. Advances that aid in the development and optimization of multiplex rtPCR-based assays, such as primer design software and novel rtPCR reagents, are also reviewed. Multiplex PCR is a technique in which the amplification and detection of two or more target DNA or RNA sequences in a single reaction are accomplished through the use of specific primers or a combination of specific primers and probes. Microarrays have been utilized to measure the levels of expression of genes, to identify single-nucleotide polymorphisms, and to genotype organisms. Another technology that is being utilized is the reverse line-blot hybridization assay (mPCR/RLB). This method in combination with multiplex PCR has been reported to provide some benefits over microarray methods. Bead-based suspension array technology is being utilized currently for antigen-, protein-, and nucleotide-based detection assays. New technologies and new platforms for high-throughput DNA sequencing are reaching maturity and should soon be available for routine use in diagnostic laboratories. With concomitant advances in the fields of microfluidics, nucleotide and fluorescent dye chemistries, and information processing, highly multiplexed nucleic acid detection and identification technologies will gradually come to be applied in a vast range of situations in which sensitivity, specificity, and speed are indispensable.

PurposeThe purpose of this paper is to discuss an academic library's need to engage all available resources to provide the services required by the changing uses, formats, and production of information.Design/methodology/approachThe paper uses the @One service environment as a case study. The service and staffing model employed a sample of 20 students and professionals who work at the @One desk. Attitudes toward the @One space were assessed through one‐on‐one interviews using two different interview protocols. Participants were asked open‐ended questions that allowed them to talk at length in response.FindingsIt is found that the University of Nevada, Reno's Mathewson‐IGT Knowledge Center has implemented a highly interactive service environment in support of production‐intensive information technologies. Professionals from numerous information disciplines participate in staffing the department, but student staff constitute the core of service delivery.Originality/valueThis paper provides information on an interactive staffing model in a US university.

Complex interactions between microbial residents of mosquitoes and arboviruses are likely to influence many aspects of vectorial capacity and could potentially have profound effects on patterns of arbovirus transmission. Such interactions have not been well studied for West Nile virus (WNV, Flaviviridae, Flavivirus) and Culex spp. mosquitoes. We utilized next-generation sequencing of 16S ribosomal RNA bacterial genes derived from Culex pipiens Linnaeus following WNV exposure and/or infection and compared bacterial populations and broad immune responses to unexposed mosquitoes. Our results demonstrate that WNV infection increases the diversity of bacterial populations and is associated with up-regulation of classical invertebrate immune pathways including RNA interference (RNAi), Toll, and Jak-STAT (Janus kinase-Signal Transducer and Activator of Transcription). In addition, WNV exposure alone, without the establishment of infection, results in similar alterations to microbial and immune signatures, although to a lesser extent. Multiple bacterial genera were found in greater abundance inWNV-exposed and/or infected mosquitoes, yet the most consistent and notable was the genus Serratia.

Objective Evidence-based sets of medical orders for the treatment of patients with common conditions have the potential to induce greater efficiency and convenience across the system, along with more consistent health outcomes. Despite ongoing utilization of order sets, quantitative evidence of their effectiveness is lacking. In this study, conducted at Advocate Health Care in Illinois, we quantitatively analyzed the benefits of community acquired pneumonia order sets as measured by mortality, readmission, and length of stay (LOS) outcomes. Methods In this study, we examined five years (2007–2011) of computerized physician order entry (CPOE) data from two city and two suburban community care hospitals. Mortality and readmissions benefits were analyzed by comparing “order set” and “no order set” groups of adult patients using logistic regression, Pearson’s chi-squared, and Fisher’s exact methods. LOS was calculated by applying one-way ANOVA and the Mann-Whitney U test, supplemented by analysis of comorbidity via the Charlson Comorbidity Index. Results The results indicate that patient treatment orders placed via electronic sets were effective in reducing mortality [OR=1.787; 95% CF 1.170-2.730; P =.061], readmissions [OR=1.362; 95% CF 1.015-1.827; P =.039], and LOS [F (1,5087)=6.885, P =.009, 4.79 days (no order set group) vs. 4.32 days (order set group)]. Conclusion Evidence-based ordering practices have the potential to improve pneumonia outcomes through reduction of mortality, hospital readmissions, and cost of care. However, the practice must be part of a larger strategic effort to reduce variability in patient care processes. Further experimental and/or observational studies are required to reduce the barriers to retrospective patient care analyses. Keywords: evidence-based medicine, medication order sets, health outcomes research, pneumonia, computerized physician order entry (CPOE).

Evidence-based order sets for treatment of patients with common conditions promise ordering efficiency and more consistent health outcomes. Despite ongoing utilization of order sets, quantitative evidence of their effectiveness is lacking. This study quantitatively analyzed benefits of CHF order sets as measured by mortality, readmission, and length of stay (LOS) outcomes.Mortality and readmissions were analyzed by comparing "order set" and "free text" groups of adult patients using logistic regression, Pearson chi-squared, and Fisher's exact methods. LOS was calculated by applying One-Way ANOVA and Mann-Whitney tests, supplemented by comorbidity analysis via Charlson Comorbidity Index.CHF orders placed via sets were effective in reducing mortality [OR=1.818;95% CF 1.039-3.181;p=0.034] and LOS [F(1,10938)=8.352,p=0.013,4.75 days ("free text" group) vs. 5.46 days ("order set" group)], while readmission outcome was not significant [OR=0.913;95% CF 0.734-1.137;p=0.417].Evidence-based medication ordering practices to treat CHF have potential to reduce mortality and LOS, without effect on readmissions.

We examined the effect of mutation of two sortase genes of Bacillus anthracis , srtA and srtB , on the ability of the bacterium to grow in J774A.1 cells, a mouse macrophage-like cell line. While disruption of either srtA or srtB had no effect on the ability of the bacteria to grow in rich culture media, mutations in each of these genes dramatically attenuated growth of the bacterium in J774A.1 cells. Complementation of the mutation restored the ability of bacteria to grow in the cells. Since the initial events in inhalation anthrax are believed to be uptake of B. anthracis spores by alveolar macrophages followed by germination of the spores and growth of the bacteria within the macrophages, these results suggest that two sortases of B. anthracis may be critical in the early stages of inhalation anthrax.

Summary The Dot/Icm type IV secretion system of Legionella pneumophila is essential for evasion of endocytic fusion and for activation of caspase-3 during early stages of infection of macrophages, but the mechanisms of manipulating these host cell processes are not known. Here, we show that caspase-3 activation by L. pneumophila is independent of all the known apoptotic pathways that converge on the activation of caspase-3. The cytoplasmic proteins IcmS, IcmR and IcmQ, which are involved in secretion of Dot/Icm effectors, are required for caspase-3 activation. Pretreatment of U937 macrophages and human peripheral blood monocytes (hPBM) with the capase-3 inhibitor (DEVD-fmk) or the paninhibitor of caspases (Z-VAD-fmk) before infection blocks intracellular replication of L. pneumophila in a dose-dependent manner. Inhibition of caspase-3 results in co-localization of the L. pneumophila-containing phagosome (LCP) with the late endosomal/lysosomal marker Lamp-2, and the LCP contains lysosomal enzymes, similar to the dotA mutant, which is defective in caspase-3 activation. However, activation of caspase-3 before infection does not rescue the replication defect of the dotA mutant. Interestingly, inhibition of caspase-3 after a 15 or 30 min infection period by the parental strain has no detectable effect on the formation of a replicative niche. The Dot/Icm-mediated activation of caspase-3 by L. pneumophila specifically cleaves, in a dose- and time-dependent manner, the Rab5 effector Rabaptin-5, which maintains Rab5-GTP on the endosomal membrane. In addition, PI3 kinase, which is a crucial effector of Rab5 downstream of Rababptin-5, is not required for intracellular replication. Using single-cell analysis, we show that apoptosis is not evident in the infected cell until bacterial replication results in > 20 bacteria per cell. We conclude that activation of caspase-3 by the Dot/Icm virulence system of L. pneumophila is essential for halting biogenesis of the LCP through the endosomal/lysosomal pathway, and that this is associated with the cleavage of Rabpatin-5.

This workshop addressed the experiences at the University of Nevada, Reno, as they discontinued check-in for print journals. The presenters reviewed the circumstances that led to this decision, such as the reduced number of print subscriptions and the increasing number of electronic journals in the collection. The Libraries also stopped binding the majority of their journals, and claiming is based more on shelf reviews than check-in records. Nearly a year after implementing this decision, the presenters deem it a success.

Legionella pneumophila is a facultative intracellular pathogen that accounts for the majority of cases of Legionnaires' disease in the USA and Europe, but other Legionella spp. have been shown to cause disease. In contrast, Legionella longbeachae is the leading cause of Legionnaires' disease in Australia. The hallmark of Legionnaires' disease caused by L. pneumophila is the intracellular replication within phagocytes in the alveolar spaces, and the Dot/Icm type IV secretion system is essential for intracellular replication. Although it has been presumed that intracellular replication within phagocytes is the hallmark of other virulent legionellae, the virulence traits of Legionella spp. apart from L. pneumophila are not well defined. In this study, 27 strains of Legionella spp. belonging to 16 species that have been isolated from humans or from the environment were examined for five virulence traits exhibited by L. pneumophila: cytopathogenicity, intracellular replication within macrophages, induction of apoptosis/DNA fragmentation, pore-formation-mediated cytolysis of the host cell, and the presence of the dot/icm loci. The strains were divided into two broad groups (low and high cytopathogenic groups) based on cytopathogenicity assays using U937 human-derived macrophages. The other four virulence traits were evaluated in the low and high cytopathogenic groups of Legionella species. Most L. pneumophila serogroup 1 strains were highly cytopathogenic after 72 h, manifested high levels of intracellular growth, induced apoptosis/DNA fragmentation, and exhibited pore-forming activity. The majority of the other species were the low cytopathogenic group that did not induce apoptosis, neither did they exhibit pore-forming activity. All the species of legionellae tested have all the dot/icm loci, when examined by DNA hybridization. No correlation was found between cytopathogenicity and the other four pathogenic traits.

This paper presents a method for the extraction of contour lines and other geographic information from scanned color images of topographical maps. Although topographic maps are available from many suppliers, this work focuses on United States Geological Survey (USGS) maps. The extraction of contour lines, which are shown with brown color on USGS maps, is a difficult process due to aliasing and false colors induced by the scanning process and due to closely spaced and intersecting/overlapping features inherent to the map. These difficulties render simple approaches such as clustering ineffective. The proposed method overcomes these difficulties using a multistep process. First, a color key set, designed to comprehend color aliasing and false colors, is generated using an eigenvector line-fitting technique in RGB space. Next, area features, representing vegetation and bodies of water, are extracted using RGB color histogram analysis in order to simplify the next stage. Then, linear features corresponding to roads and rivers including contours, are extracted using a valley seeking algorithm operating on a transformed version of the original map. Finally, an A* search algorithm is used to link valleys together to form linear features and to close the gaps caused by intersecting features. The performance of the algorithm is tested on a number of USGS topographic map samples.

The final step of the intracellular life cycle of Legionella pneumophila and other intracellular pathogens is their egress from the host cell after termination of intracellular replication. We have previously isolated five spontaneous mutants of L. pneumophila that replicate intracellularly similar to the wild-type strain but are defective in pore formation-mediated cytolysis and egress from mammalian and protozoan cells, and the mutants have been designated rib (release of intracellular bacteria). Here, we show that the rib mutants are not defective in the activity of enzymes secreted through the type II secretion system, including phospholipase A, lysophospholipase A, and monoacylglycerol lipase, although they are potential candidates for factors that lyse host cell membranes. In addition, the pilD and lspG mutants, which are defective in the type II secretion system, are not defective in the pore-forming toxin. We show that all five rib mutants have an identical point mutation (deletion) following a stretch of poly(T) in the icmT gene. Spontaneous revertants of the rib mutants, due to an insertion of a nucleotide following the poly(T) stretch in icmT, have been isolated and shown to have regained the wild-type phenotype. We constructed an icmT insertion mutant (AA100kmT) in the chromosome of the wild-type strain by allelic exchange. The AA100kmT mutant was as defective as the rib mutant in pore formation-mediated cytolysis and egress from mammalian and protozoan cells. Both the rib mutant and the AA100kmT mutant were complemented by the icmT gene for their phenotypic defect. rtxA , a gene that is thought to have a minor role in pore formation, was not involved in pore formation-mediated cytolysis and egress from mammalian and protozoan cells. We conclude that the icmT gene is essential for pore formation-mediated lysis of mammalian and protozoan cells and the subsequent bacterial egress.

In vivo propagation of [PSI(+)], an aggregation-prone prion isoform of the yeast release factor Sup35 (eRF3), has previously been shown to require intermediate levels of the chaperone protein Hsp104. Here we perform a detailed study on the mechanism of prion loss after Hsp104 inactivation. Complete or partial inactivation of Hsp104 was achieved by the following approaches: deleting the HSP104 gene; modifying the HSP104 promoter that results in low level of its expression; and overexpressing the dominant-negative ATPase-inactive mutant HSP104 allele. In contrast to guanidine-HCl, an agent blocking prion proliferation, Hsp104 inactivation induced relatively rapid loss of [PSI(+)] and another candidate yeast prion, [PIN(+)]. Thus, the previously hypothesized mechanism of prion dilution in cell divisions due to the blocking of prion proliferation is not sufficient to explain the effect of Hsp104 inactivation. The [PSI(+)] response to increased levels of another chaperone, Hsp70-Ssa, depends on whether the Hsp104 activity is increased or decreased. A decrease of Hsp104 levels or activity is accompanied by a decrease in the number of Sup35(PSI+) aggregates and an increase in their size. This eventually leads to accumulation of huge agglomerates, apparently possessing reduced prion forming capability and representing dead ends of the prion replication cycle. Thus, our data confirm that the primary function of Hsp104 in prion propagation is to disassemble prion aggregates and generate the small prion seeds that initiate new rounds of prion propagation (possibly assisted by Hsp70-Ssa).

Propagation of the yeast protein-based non-Mendelian element [PSI], a prion-like form of the release factor Sup35, was shown to be regulated by the interplay between chaperone proteins Hsp104 and Hsp70. While overproduction of Hsp104 protein cures cells of [PSI], overproduction of the Ssa1 protein of the Hsp70 family protects [PSI] from the curing effect of Hsp104. Here we demonstrate that another protein of the Hsp70 family, Ssb, previously implicated in nascent polypeptide folding and protein turnover, exhibits effects on [PSI] which are opposite those of Ssa. Ssb overproduction increases, while Ssb depletion decreases, [PSI] curing by the overproduced Hsp104. Both spontaneous [PSI] formation and [PSI] induction by overproduction of the homologous or heterologous Sup35 protein are increased significantly in the strain lacking Ssb. This is the first example when inactivation of an unrelated cellular protein facilitates prion formation. Ssb is therefore playing a role in protein-based inheritance, which is analogous to the role played by the products of mutator genes in nucleic acid-based inheritance. Ssb depletion also decreases toxicity of the overproduced Sup35 and causes extreme sensitivity to the [PSI]-curing chemical agent guanidine hydrochloride. Our data demonstrate that various members of the yeast Hsp70 family have diverged from each other in regard to their roles in prion propagation and suggest that Ssb could serve as a proofreading component of the enzymatic system, which prevents formation of prion aggregates.

Based on the relatively scarce data and literature on information technology (IT) utilization as well as a sample survey of 44 Jordanian public agencies, this study examines the adoption and uses of IT in the Jordanian public sector. The findings show that the majority of Jordanian public organizations have access to computers, and most of the agencies have in-house systems. Microcomputers were found to be the most common computer platform, and agency use of IT was consistently intense in the area of financial management. Most public organizations with in-house computers employ on-staff programmers, whose numbers range from one to four or fewer. Software being used in the agencies was primarily commercially produced, but there was evidence of considerable internal development of software as well. The study concludes that current, specific agency use of computing is associated positively with plans to acquire additional microcomputer technology. In addition, an overview of emerging Internet activity in Jordan and the government’s role in this still emerging phenomenon is presented.

In 1997, the U.S. Joint Committee on Printing (JCP) drafted legislation to modify Title 44 of the United States Code. The two goals of the proposed legislation were: (1) to protect public access to government information and (2) to resolve the constitutional question concerning the relationship between the Government Printing Office and the executive branch. This effort, is being spearheaded by Eric C. Peterson, JCP Staff Director. This interview with Mr. Peterson describes the legislation, its purpose, and the Committee’s efforts to gain passage of such legislation during the 105th Congress. Published by Elsevier Science Ltd