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W-band (75-110 GHz) is proposed nowadays as a valuable alternative to intensively-exploited Ku- and Ka-bands for high-speed transmission over satellite networks. In such a framework, some experiments are being carried out, which are targeted to verify the feasibility of exploitation of W-band for broadband service deployment. From a theoretical viewpoint, the large bandwidth availability and the scarce amount of interference typical of W-band should guarantee high capacities. Nevertheless, many crucial aspects are still to be carefully investigated, e.g., signal propagation issues, RF impairments, choice of modulation and coding, efficient antenna design, etc. In this paper, an overview is made on the low Earth orbit (LEO) nano-satellite mission in-orbit key-test and validation of W-band (IKNOW). IKNOW mission is an ongoing advanced feasibility study part of an Italian Space Agency Project, named W-band analysis and verification (WAVE), coordinated by the Department of Electronic Engineering, University of Rome ldquoTor Vergatardquo. The main objective of the IKNOW mission is to tackle some of the unexplored critical aspects concerning W-band satellite transmission. In such a perspective, IKNOW should be regarded as a ldquopilot mission,rdquo whose results will be used for a first uplink-downlink satellite channel characterization, in-orbit validation of W-band technology, and space qualification processes. This paper is focused on the research work carried out in a preliminary phase of the IKNOW study and will also consider a number of elements related to the mission configuration, payload architecture, link analysis, potential RF impairment factors, and atmospheric effects. Proposed analysis and preliminary results shown can provide to interested readers the basic guidelines that will drive the practical implementation of IKNOW mission, as well as the most relevant issues to be faced by future developers of W-band missions using small LEO satellites. [ABSTRACT FROM PUBLISHER]

Summarizes the clinical course and exposure history of two rapidly fatal cases of rat-bite fever (RBF) in Washington and Florida identified by the U.S. Centers for Disease Control and Prevention Unexplained Deaths and Critical Illnesses (UNEX) Project in 2003. Importance of including RBF in the differential diagnoses of acutely ill patients with reported rat exposures; Significance of preventing zoonotic infections among persons with occupational or recreational exposure to rats; Length of time before patients in the described cases died.

The aim of the present work was to develop a loneliness scale for adolescents in order to assess their perceptions of the quality of their relationships with parents and peers. The scale was administered to 1,233 Argentine secondary school students, aged 13-16 years. Factor analyses (principal axes, oblimin solution) were conducted. Four factors were obtained, which accounted for 43.13% of the variance: Peer Rejection, Family Deficits and Parent Rejection, Personal Inadequacy, and Significant Separation. The internal consistency assessed through Cronbach's alpha was satisfactory. We believe that this proposal, which aims at evaluating the different processes that cause and are caused by a feeling of loneliness, allows for an integral approach to the issue. [ABSTRACT FROM AUTHOR]

Presents views on public health issues and concerns. Epidemic occurrence of Neisseria meningitis serogroup W135 in Saudi Arabia; Cases of human gnathosmosis in Mexico; Report on human granulocytic ehrlichiosis in France; Phylogenetic analysis of the Chinese Rickettsia isolate BJ-90.

Plants exhibit a range of responses in growth and reproduction to attack by herbivores from loss, to no effect, to overcompensation. We assessed herbivore impact on branch architecture, growth, and sexual reproduction by flowering dogwood, Cornus florida, for four years after attack by a specialist stem gall-forming fly, Resseliella clavula. We estimated the immediate and long-term consequences of herbivory for vegetative growth and flower and fruit production on marked shoots that were galled or ungalled at the outset of our study. The responseof dogwood trees to herbivory was complex with an initial negative effect on flower and fruit production, followed by compensatory shoot elongation and inflorescence production after three years, and a tendency toward overcompensation after four years. When observations on fruit production were terminated at the end of year three, fruit production on galled shoots was still suppressed relative to ungalled shoots. Attack by the gall-former in the initial year of the study causedan immediate reduction in shoot survival and a 46% decrease in inflorescence and 79% loss in fruit production relative to ungalled shoots. After four years, compensation in both vegetative growth and inflorescence production was detected. A tendency toward overcompensation within the fourth year was indicated by 24% greater shoot elongation and 90% more inflorescence production on galled shoots than on ungalled shoots. Compensation in vegetative growth on surviving galled shoots involved increases in the average length and the number of vegetative modules produced. Reproductive compensation occurred because a greater number of vegetative modules gave rise to reproductive buds on galled shoots than on ungalled shoots in the third and fourth years ofthe study. Our results suggest that in long-lived species, the initial response of the plant may not be an adequate measure of the impactof herbivores on plant fitness. Responses to herbivores may extend for s [ABSTRACT FROM AUTHOR]