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Broadband telecommunication service is growing rapidly and its economic impact is likely to vary considerably around the globe. Considerable interest is being shown in wireless broadband, especially in low income and rural areas. This study focuses on the direct effect (broadband penetration as an input), and separately, the productive efficiency effect of broadband (as an information network externality), using a model developed in Thompson and Garbacz (2007). Aggregate fixed and mobile broadband usage and their effect are analyzed and compared first on a sample of forty-three countries with sufficient data. The same models are used on samples of high income and low income countries. It is hypothesized that the rapid growth of broadband could have a stronger effect for low income countries and their initial levels of network development. Key variables are adjusted to a per household basis, using information on household size. Due to the endogeneity of key variables, instrumental variables are employed to estimate separate equations for mobile broadband and fixed broadband. Predicted values for these variables are used in the final equations in order to adjust for endogeneity and omitted variable bias. The results of the model estimated for the full sample indicate that mobile broadband has an important direct effect on GDP, but fixed broadband has an effect no different than zero. In the models with high and low income samples it is apparent that low income countries derive significantly more benefit from mobile broadband. Estimates from the Stochastic Frontier Model find mobile broadband to be a significant driver of growth via a reduction of inefficiency.

Analysis of the Coxiella burnetii RSA 493 (Nine Mile phase I strain) genome revealed ORFs with significant homology to the type IVB secretion system (T4BSS) of Legionella pneumophila . The T4BSS genes exist primarily at two loci, designated regions I (RI) and II. In C. burnetii , little is known about the T4BSS regions and the role they play in establishing and/or maintaining infection. Coxiella burnetii T4BSS RI contains genes arranged in three linkage groups: (1) icmW →CBU1651→ icmX , (2) icmV → dotA →CBU1647, and (3) icmT → icmS → dotD → dotC → dotB →CBU1646. We used reverse transcriptase (RT)-PCR to demonstrate transcriptional linkage within the groups, and that icmX , icmV , and icmT are transcribed de novo by 8 h post infection (hpi). We then examined the transcript levels for icmX , icmW, icmV , dotA, dotB , and icmT during the first 24 h of an infection using quantitative RT-PCR. The expression initially increased for each gene, followed by a decrease at 24 hpi. Subsequently, we analyzed IcmT protein levels during infection and determined that the expression increases significantly from 8 to 24 hpi and then remains relatively constant. These data demonstrate temporal changes in the RNA of several C. burnetii T4SS RI homologs and the IcmT protein. These changes correspond to early stages of the C. burnetii infectious cycle.

Our multivariate model finds smoke detector impact on the fire death rate has an elasticity of − 0.10, similar to Garbacz [Garbacz, C., 1989. Smoke Detector Effectiveness And The Value Of Saving A Life, Economics Letters, 31, 281–286.] using pre-saturation detector data. Public health estimates are − 0.45. Additionally, we find that cigarette smoking has ten times the impact of detectors.

Living standards and economic growth in developing countries are invariably linked to the availability and use of telecom services. Effective policy decisions require the best estimates of the drivers of these services. In this paper, telecommunications demand is estimated in models for residential mainline and mobile telephone service for developing countries for the period 1996-2003. The paper tests for cross-price effects between mainline and mobile service and its findings have important policy implications. It finds residential monthly price elasticity to be insignificant for developing countries, but the connection elasticity is larger than generally found in the literature. Mobile monthly price elasticities are very large. A new and important empirical finding is that although wireline phones are substitutes in the mobile market, the contrary is not true-mobile phones are not substitutes in the wireline market, and in fact may be considered complements. This lack of symmetry has important implications for properly defining telecom markets. Universal service subsidies and competitive market initiatives should be reevaluated in light of the paper's elasticity estimates. Increased competition, income growth and enhanced education may be the ultimate universal service promoters.

The O-antigen-encoding region in the genomes of 14 isolates of Coxiella burnetii was examined by PCR. Five phase I isolates (Nine Mile clone 7, KAV, Ohio, Henzerling RSA 343, Q173) were analyzed and no deletions were detected. Two other isolates of unknown phase (Scottish, WAV) were examined, but no deletions were detected. In contrast, RSA 514 and three phase II isolates (Nine Mile phase II clone 4, Nine Mile phase II clone 1, Nine Mile Baca) contained large deletions, and the latter two were further characterized by DNA sequencing. Three other phase II isolates (Henzerling RSA 331, M44, Australian QD) contained no apparent deletions. Reactivity to phase I- and phase II-specific antibodies by immunofluorescence assay was used to further characterize isolates. Selected ORFs in Australian QD and M44 DNA were sequenced to detect mutations, and no significant changes were found. Australian QD RNA was examined by reverse transcriptase-PCR specific to the four ORFs hypothesized to encode the O-antigen sugar virenose, which this isolate has been shown to lack, as well as one that is predicted to encode part of the O-antigen ABC transporter. Each of these five genes was found to be expressed.

Although Q fever is considered enzootic in the United States, surveillance for human Q fever has been historically limited. From 1978 through 1999, 436 cases (average = 20 per year) of human Q fever were reported. After Q fever became nationally reportable in 1999, 255 human Q fever cases (average = 51 per year) were reported with illness onset during 2000 through 2004. The median age of cases was 51 years, and most cases were male (77%). The average annual incidence of Q fever was 0.28 cases per million persons, and was highest in persons 50-59 years of age (0.39 cases per million). State-specific incidence ranged from a high of 2.40 cases per million persons in Wyoming, to 0 cases in some states. Since Q fever became reportable, case reports have increased by more than 250%. Surveillance for Q fever is essential to establish the distribution and magnitude of disease and to complement U.S. bioterrorism preparedness activities.

The order Rickettsiales consists of the family Rickettsiaceae and the family Anaplasmataceae. The family Rickettsiaceae contains the genus Rickettsia and the genus Orientia. Members of the family Rickettsiaceae are short rods or coccobacilli, and members of the family Anaplasmataceae are small pleomorphic cocci. The family Bartonellaceae consists of two genera, one of which, Bartonella, includes human pathogens belonging to the α2-group proteobacteria. Currently, the principal techniques used for the serodiagnosis of rickettsial diseases are probe-based immunoassays. Immunoprobe-based tests include the indirect fluorescence assay (IFA) and its micromodification, the micro-IF (MIF) test. The MIF test is still considered as the gold standard. Other immunoprobe tests include immunoperoxidase assays (IPAs); enzyme-linked immunosorbent assays (ELISAs), in which the antigens are adsorbed either onto the well of a microtiter plate or onto nitrocellulose in a dot blot or slot blot configuration; and immunoblot assays (IBAs). IFAs and IPAs require the whole bacterium as the antigen. The remaining immunoprobe assays use either highly purified rickettsiae or an extract. The development of real-time PCR-based diagnosis and rapid PCR-based diagnostic methods has been the focus of much attention in many research laboratories. Recently, a protein-based method for the detection of the small-cell variant protein A (ScvA) plus other protein markers comprising a Coxiella fingerprint via matrix-assisted laser desorption-time of flight (MALDI-TOF) mass spectrometry has been developed.

The 1,995,275-bp genome ofCoxiella burnetii, Nine Mile phase I RSA493, a highly virulent zoonotic pathogen and category B bioterrorism agent, was sequenced by the random shotgun method. This bacterium is an obligate intracellular acidophile that is highly adapted for life within the eukaryotic phagolysosome. Genome analysis revealed many genes with potential roles in adhesion, invasion, intracellular trafficking, host-cell modulation, and detoxification. A previously uncharacterized 13-member family of ankyrin repeat-containing proteins is implicated in the pathogenesis of this organism. Although the lifestyle and parasitic strategies ofC. burnetiiresemble that ofRickettsiaeandChlamydiae, their genome architectures differ considerably in terms of presence of mobile elements, extent of genome reduction, metabolic capabilities, and transporter profiles. The presence of 83 pseudogenes displays an ongoing process of gene degradation. Unlike other obligate intracellular bacteria, 32 insertion sequences are found dispersed in the chromosome, indicating some plasticity in theC. burnetiigenome. These analyses suggest that the obligate intracellular lifestyle ofC. burnetiimay be a relatively recent innovation.

Adding the 2000 decennial census data to our pooled logit model results in much stronger evidence that targeted subsidy programs to add poor households to the network are ineffective and very costly. Untargeted programs are about nine times more expensive than targeted programs. Overall higher penetration rates are fueled by the declining real price of access and rapid income growth in the 1990s. In addition, our estimate of the first integrated access and new services model with 2000 decennial census data suggests that cell phones and Internet are, in part, responsible for the recent surge in penetration, but precise estimates are difficult without price information.

After repeated passages through embyronated eggs, the Nine Mile strain ofCoxiella burnetiiexhibits antigenic variation, a loss of virulence characteristics, and transition to a truncated lipopolysaccharide (LPS) structure. In two independently derived strains, Nine Mile phase II and RSA 514, these phenotypic changes were accompanied by a large chromosomal deletion (M. H. Vodkin and J. C. Williams, J. Gen. Microbiol.132:2587-2594, 1986). In the work reported here, additional screening of a cosmid bank prepared from the wild-type strain was used to map the deletion termini of both mutant strains and to accumulate all the segments of DNA that comprise the two deletions. The corresponding DNAs were then sequenced and annotated. The Nine Mile phase II deletion was completely nested within the deletion of the RSA 514 strain. Basic alignment and homology studies indicated that a large group of LPS biosynthetic genes, arranged in an apparent O-antigen cluster, was deleted in both variants. Database homologies identified, in particular, mannose pathway genes and genes encoding sugar methylases and nucleotide sugar epimerase-dehydratase proteins. Candidate genes for addition of sugar units to the core oligosaccharide for synthesis of the rare sugar 6-deoxy-3-C-methylgulose (virenose) were identified in the deleted region. Repeats, redundancies, paralogous genes, and two regions with reduced G+C contents were found within the deletions.

Coxiella burnetii can be transformed to ampicillin resistance by electroporation with plasmids encoding beta-lactamase. However, non-plasmid emergence of resistance to ampicillin also develops. To validate the usefulness of the bla gene marker for selection and detection, transformed C. burnetii were examined for beta-lactamase expression by use of immunoblotting after SDS-PAGE. The 29-kDa mature form of the beta-lactamase protein was detected in C. burnetii lysates. Quantitation of these immunoblot signals showed that C. burnetii surprisingly expressed low levels of beta-lactamase. The results validate the use of plasmid-encoded ampicillin resistance as a means for selecting C. burnetii transformants; they also suggest that levels of ampicillin used for selection pressure should be empirically determined and that detection of beta-lactamase by antibody blotting done to confirm transformants.

In an active market for generation assets prompted by deregulation, some nuclear plants will command higher market prices, but the unresolved issue of stranded costs will continue to be a drag. Controlled deregulation of nuclear assets may provide an interim solution.

We estimate an aggregate production frontier using time-series data for the private U.S. economy and show that estimated technical inefficiency is negatively correlated with the stock of public capital, or infrastructure. We then estimate a production frontier which includes a public-capital variable and report that this variable has no statistically significant effect on private productivity. Our results suggest that public capital affects private productivity indirectly by reducing aggregate technical inefficiency rather than directly by increasing output. Consequently, previous evidence indicating a positive, direct effect of public capital on average private-sector output may have been obtained from stochastically misspecified models.

We describe a fatal pediatric case of Rocky Mountain spotted fever in Panama, the first, to our knowledge, since the 1950s. Diagnosis was established by immunohistochemistry, PCR, and isolation of Rickettsia rickettsii from postmortem tissues. Molecular typing demonstrated strong relatedness of the isolate to strains of R. rickettsii from Central and South America.

Direct analysis in real time (DART) is implemented on a time-of-flight (TOF) mass spectrometer, and used for the generation of fatty acid methyl esters (FAMEs) ions from whole bacterial cells.

A 5.8-kb chromosomal fragment isolated from Coxiella burnetii initiates plasmid replication in Escherichia coli and was characterized as an autonomous replication sequence, ars (M. Suhan, S.-Y. Chen, H.A. Thompson, T.A. Hoover, A. Hill, and J.C. Williams, J. Bacteriol. 176:5233-5243, 1994). In the present study, an ars replicon was used to transform C. burnetii to ampicillin resistance. Plasmid pSKO(+)1000 contained the C. burnetii ars sequence cloned into a ColE1-type replicon encoding beta-lactamase. pSKO(+)1000 was introduced into C. burnetii by electroporation. Ampicillin-resistant cells were selected, and survivors were examined for the transformed genotype by Southern hybridization. Transformants stably maintained the pSKO(+)1000 bla DNA sequence in the chromosome as a result of homologous recombination. The recombination event resulted in the duplication of the 5.8-kb ars sequence in the C. burnetii chromosome. The bla gene was also located in an episome. However, an ampicillin resistance plasmid lacking the C. burnetii ars sequence did not stably transform C. burnetii. A biological assay analyzing beta-lactamase activity of C. burnetii transformants during acid activation in vitro provided evidence for expression of the bla (beta-lactamase) gene.

A recent FBI survey reported that the average cost of a successful attack by a malicious insider is nearly 50 times greater than the cost of an external attack. Further, it is estimated that over 80% of information security incidents for the past four years are the result of insiders. Intrusion detection systems have traditionally targeted those who attack outside of trusted network boundaries. What is desperately needed are mechanisms that monitor insider activity and detect actions at the host level that may be malicious. This paper presents an overview of innovative approaches to detect malicious insiders who operate inside trusted network boundaries.

Considerable controversy surrounds the role of money in the production of goods and services. Previous empirical research has appeared to find that the real money stock affects aggregate output, holding other, more conventional inputs constant. However, the theoretical literature offers no convincing explanation for this empirical finding. One interpretation is that real money balances reduce the extent to which labor and capital are diverted into exchange-related activities instead of being used in production defined in a more narrow sense. To investigate this hypothesis, we estimate a production function augmented with real money balances as an input, using time-series data for the aggregate U.S. economy. A stochastic production frontier is then estimated without real money balances. We use these estimates to establish the presence of technical inefficiency. Finally, we show that the extent of technical inefficiency is negatively correlated with the real money stock. Our results provide a reconciliation between the empirical literature, which finds that real money balances affect output in a production function framework, and the theoretical literature, which suggests that real money balances enhance the technical efficiency of the economy.

This study investigates whether the structure of customer rates for US electric utilities with nuclear power generation is significantly different from the rate structure of non-nuclear utilities. Using previous estimates of the marginal costs of generation by nuclear and fossil-fuel plants, and of transmission and distribution, tests are made to determine if pricing practices are similar in nuclear and non-nuclear jurisdictions. The results show that the rate structure for the nuclear utilities is inefficient, with industrial rates significantly higher than first-best or second-best pricing criteria allow, whereas the rates for non-nuclear utilities are second-best efficient, with a slight favouritism toward the industrial class.

Viable Coxiella burnetii organisms were isolated from the culture medium of persistently infected Baby Hamster Kidney (BHK-21) fibroblasts. When these organisms were incubated in host-cell-free medium at low pH, some of the de novo-synthesized protein made by the bacteria was translocated to the exterior of the cell. The exported protein was detectable after 2-7 h incubation at 37 degrees C. No evidence was found to suggest that protein accumulation in the medium was due to leakiness caused by cell damage. Both DCCD (dicyclohexylcarbodiimide) and CCCP (carbonyl cyanide m-chlorophenylhydrazone) inhibited the process to some extent. Exported protein was represented largely by three polypeptides with molecular masses of 34, 24 and 12 kDa. De novo-synthesized proteins corresponding to these molecular masses were not detected in cytoplasmic fractions, but a membrane fraction might possess a similar form. It was concluded that a physiological process of protein translocation occurred in C. burnetii during acid activation in a defined medium. Organisms that were extracted directly from the cytoplasm of infected fibroblasts by a mechanical disruption procedure were also active in de novo protein synthesis; however they exported much less of the protein.

DOE funding was used to renovate 4,500 square feet of aging laboratories and classrooms that support science, engineering, and mathematics disciplines (specifically environmental science, and computer engineering). The expansion of the labs was needed to support robotics and environmental science research, and to better accommodate a wide variety of teaching situations. The renovated space includes a robotics laboratory, two multi-use labs, safe spaces for the storage of instrumentation, modern ventilation equipment, and other “smart” learning venues. The renovated areas feature technologies that are environmentally friendly with reduced energy costs. A campus showcase, the laboratories are a reflection of the University’s commitment to the environment and research as a tool for teaching. As anticipated, the labs facilitate the exploration of emerging technologies that are compatible with local and regional economic plans.

A Coxiella burnetii chromosomal fragment capable of functioning as an origin for the replication of a kanamycin resistance (Kanr) plasmid was isolated by use of origin search methods utilizing an Escherichia coli host. The 5.8-kb fragment was subcloned into phagemid vectors and was deleted progressively by an exonuclease III-S1 technique. Plasmids containing progressively shorter DNA fragments were then tested for their capability to support replication by transformation of an E. coli polA strain. A minimal autonomous replication sequence (ARS) was delimited to 403 bp. Sequencing of the entire 5.8-kb region revealed that the minimal ARS contained two consensus DnaA boxes, three A + T-rich 21-mers, a transcriptional promoter leading rightwards, and potential integration host factor and factor of inversion stimulation binding sites. Database comparisons of deduced amino acid sequences revealed that open reading frames located around the ARS were homologous to genes often, but not always, found near bacterial chromosomal origins; these included identities with rpmH and rnpA in E. coli and identities with the 9K protein and 60K membrane protein in E. coli and Pseudomonas species. These and direct hybridization data suggested that the ARS was chromosomal and not associated with the resident plasmid QpH1. Two-dimensional agarose gel electrophoresis did not reveal the presence of initiating intermediates, indicating that the ARS did not initiate chromosome replication during laboratory growth of C. burnetii.

This paper tests empirically the Ramsey version of the public-interest theory of regulation by examining the pricing practices in the nuclear power industry, using a 1985 cross-sectional sample of 40 electric utilities. Other researchers have avoided this segment of the industry because of difficulties with nuclear fuel data, or perceived differences in the underlying production function. We show that regulators respond to political influences according to the Stigler-Peltzman version of regulation and that Ramsey pricing cannot be validated, at least for the nuclear segment of the electric power industry.

Postexposure prophylaxis may avert Q fever illness and death when the probability of exposure is above the population-specific threshold point., Coxiella burnetii is a category B bioterrorism agent. We numerically evaluated the risks and benefits from postexposure prophylaxis (PEP) after an intentional release of C. burnetii to the general population, pregnant women, and other high-risk populations. For each group, we constructed a decision tree to estimate illness and deaths averted by use of PEP/100,000 population. We calculated the threshold points at which the number of PEP-related adverse events was equal to the cases averted. PEP was defined as doxycycline (100 mg 2×/day for 5 days), except for pregnant women, where we assumed a PEP of trimethoprim-sulfamethoxazole (160 mg/800 mg 2×/day) for the duration of the pregnancy. PEP would begin 8–12 days postexposure. On the basis of upper-bound probability estimates of PEP-related adverse events for doxycycline, we concluded that the risk for Q fever illness outweighs the risk for antimicrobial drug–related adverse events when the probability of C. burnetii exposure is >7% (pregnant women using trimethoprim-sulfamethoxazole = 16%).

Coxiella burnetii is a gram-negative obligate intracellular bacterium that must survive and replicate in an acidified phagosome of an infected host cell (Fig. 1). Most closely related to Legionella pneumophila, it is a member of the γ-proteobacteria class in the Legionellales order. First discovered in the 1930s in Australia and the United States, it is an organism with a worldwide distribution and is the causative agent of query (Q) fever in humans. C. burnetii, like Chlamydia, has a complex life cycle with at least two forms, a metabolically active large cell variant (LCV) and a spore-like small cell variant (SCV). Unlike Chlamydia, both the cell forms are infectious. Moreover, the SCV (or another resilient form, see C. burnetii Lifecycle Stages section) can survive in the environment outside a host for years while remaining infectious and is small enough to be carried and dispersed for miles by wind. These properties have renewed interest in C. burnetii, classified as a category B critical biologic agent, as a biological weapon and terror agent.

Accurate bacterial identification is important in diagnosing disease and in microbial forensics. Coxiella burnetii, a highly infective microorganism causative of the human disease Q fever, is now considered a U.S. category B potential bioterrorism agent. We report here an approach for the confirmatory identification of C. burnetii at the strain level which involves the combined use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and supervised pattern recognition via Partial Least Squares-Discriminant Analysis (PLS-DA). C. burnetii isolates investigated in this study included the following prototype strains from different geographical and/or historical origins and with different antigenic properties: Nine Mile I, Australian QD, M44, KAV, PAV, Henzerling, and Ohio. After culture and purification following standard protocols, linear MALDI-TOF mass spectra of pure bacterial cultures were acquired in positive ion mode. Mass spectral data were normalized, baseline-corrected, denoised, binarized and modeled by PLS-DA under crossvalidation conditions. Robustness with respect to uncontrolled variations in the sample preparation and MALDI analysis protocol was assessed by repeating the experiment on five different days spanning a period of 6 months. The method was validated by the prediction of unknown C. burnetii samples in an independent test set with 100% sensitivity and specificity for five out of six strain classes.

Prevalence of antibodies to Coxiella burnetii in 24 veterinary school-associated dairy herds in the United States was assessed through laboratory testing of bulk tank milk specimens by indirect immunofluorescent antibody assay. Twenty-two herds (92%) had evidence of antibodies to C. burnetii Phase I antibodies at a titer of > or = 1:16, and nine herds (38%) had Phase I antibody titers of > or = 1:256. These results suggest that C. burnetii infection is geographically widespread among dairy herds in the United States.