4,511 research outputs found
Combined electronic nose and tongue for a flavour sensing system
We present a novel, smart sensing system developed for the flavour analysis of liquids. The system comprises both a so-called "electronic tongue" based on shear horizontal surface acoustic wave (SH-SAW) sensors analysing the liquid phase and a so-called "electronic nose" based on chemFET sensors analysing the gaseous phase. Flavour is generally understood to be the overall experience from the combination of oral and nasal stimulation and is principally derived from a combination of the human senses of taste (gustation) and smell (olfaction). Thus, by combining two types of microsensors, an artificial flavour sensing system has been developed. Initial tests conducted with different liquid samples, i.e. water, orange juice and milk (of different fat content), resulted in 100% discrimination using principal components analysis; although it was found that there was little contribution from the electronic nose. Therefore further flavour experiments were designed to demonstrate the potential of the combined electronic nose/tongue flavour system. Consequently, experiments were conducted on low vapour pressure taste-biased solutions and high vapour pressure, smell-biased solutions. Only the combined flavour analysis system could achieve 100% discrimination between all the different liquids. We believe that this is the first report of a SAW-based analysis system that determines flavour through the combination of both liquid and headspace analysis
Space Transportation Materials and Structures Technology Workshop
The Space Transportation Materials and Structures Technology Workshop was held on September 23-26, 1991, in Newport News, Virginia. The workshop, sponsored by the NASA Office of Space Flight and the NASA Office of Aeronautics and Space Technology, was held to provide a forum for communication within the space materials and structures technology developer and user communities. Workshop participants were organized into a Vehicle Technology Requirements session and three working panels: Materials and Structures Technologies for Vehicle Systems, Propulsion Systems, and Entry Systems
Intelligence/Electronic Warfare (IEW) direction-finding and fix estimation analysis report. Volume 2: Trailblazer
An analysis of the direction finding (DF) and fix estimation algorithms in TRAILBLAZER is presented. The TRAILBLAZER software analyzed is old and not currently used in the field. However, the algorithms analyzed are used in other current IEW systems. The underlying algorithm assumptions (including unmodeled errors) are examined along with their appropriateness for TRAILBLAZER. Coding and documentation problems are then discussed. A detailed error budget is presented
Flora of Richmond National Battlefield Park, Virginia
An inventory of the vascular flora of nine of eleven units of Richmond National Battlefield Park was compiled from 1985 to 1987. Each site was visited during the growing season in two to four week intervals; plant species were identified and recorded in the field and/or collected for later study. A total of 761 different species were identified in the surveyed units, and 2487 individual records of species per particular park unit were noted. Twenty-three percent of the flora consists of exotic species, largely from Eurasia. Voucher specimens are housed in the herbaria of the University of Richmond and Virginia Commonwealth University
Holevo Cram\'er-Rao Bound for waveform estimation of gravitational waves
Detecting kilohertz gravitational waves from the post-merger remnants of
binary neutron-star mergers could enhance our understanding of extreme matter.
To enable this detection, a gravitational-wave interferometer can be detuned to
increase its kilohertz sensitivity. The precision limits of detuned
interferometers and other cavity--based quantum sensors, however, are not well
understood. The sensitivity of the standard variational readout scheme does not
reach the waveform-estimation Quantum Cram\'er-Rao Bound. We establish the
fundamental precision limit, the waveform-estimation Holevo Cram\'er-Rao Bound,
by identifying the incompatibility of the na\"ive estimates of the signal's
cosine and sine phases. For an equal weighting between the phases, we prove
that the standard scheme is indeed optimal. For unequal weights, however, we
propose an experimental realisation of a new measurement scheme to
significantly improve the sensitivity. This scheme could facilitate kilohertz
gravitational-wave astronomy and has broader applications to detuned
cavity--based quantum metrology.Comment: v2. Letter: 7 pages, 2 figures. Supplemental Material: 17 pages, 4
figures. Submitted on August 11 2023 to Physical Review Letter
A new classification and linear sequence of extant gymnosperms
A new classification and linear sequence of the gymnosperms based on previous molecular and morphological phylogenetic and other studies is presented. Currently accepted genera are listed for each family and arranged according to their (probable) phylogenetic position. A full synonymy is provided, and types are listed for accepted genera. An index to genera assists in easy access to synonymy and family placement of genera.Peer reviewe
Comparison of the airway microbiota in children with chronic suppurative lung disease
Rationale: The airway microbiota is important in chronic suppurative lung diseases (CSLD), such as primary ciliary dyskinesia (PCD) and cystic fibrosis (CF). This comparison has not previously been described but is important because difference between the two diseases may relate to the differing prognoses and lead to pathological insights and potentially, new treatments. Objectives: To compare the longitudinal development of the airway microbiota in children with PCD to that of CF and relate this to age and clinical status. Methods: Sixty-two age-matched children (age range 0.5–17 years) with PCD or CF (n=31 in each group) were recruited prospectively and followed for 1.1 years. Throat swabs or sputum as well as clinical information were collected at routine clinical appointments. 16S rRNA gene sequencing was performed. Measurements and Main Results: The microbiota was highly individual and more diverse in PCD and differed in community composition when compared with CF. Whilst Streptococcus was the most abundant genus in both conditions, Pseudomonas was more abundant in CF with Haemophilus more abundant in PCD (Padj=0.0005). In PCD only, an inverse relationship was seen in the relative abundance of Streptococcus and Haemophilus with age. Conclusions: Bacterial community composition differs between children with PCD and those with CF. Pseudomonas is more prevalent in CF and Haemophilus in PCD, at least until infection with Pseudomonas supervenes. Interactions between organisms, particularly members of Haemophilus, Streptococcus, and Pseudomonas genera appear important. Study of the interactions between these organisms may lead to new therapies or risk stratification
Multi-messenger astronomy with a Southern-Hemisphere gravitational-wave observatory
Joint observations of gravitational waves and electromagnetic counterparts
will answer questions about cosmology, gamma-ray bursts, and the behaviour of
matter at supranuclear densities. The addition of a Southern-Hemisphere
gravitational-wave observatory to proposed global networks creates a longer
baseline, which is beneficial for sky localisation. We analyse how an
observatory in Australia can enhance the multi-messenger astronomy capabilities
of future networks. We estimate the number of binary neutron star mergers with
joint observations of gravitational waves and kilonova counterparts detectable
by the Vera C. Rubin Observatory. First, we consider a network of upgrades to
current observatories. Adding an Australian observatory to a three-observatory
network (comprising two observatories in the USA and one in Europe) boosts the
rate of joint observations from per year to
per year (a factor of two improvement). Then, we consider a
network of next-generation observatories. Adding a km Australian
observatory to a global network of a Cosmic Explorer km in the USA and an
Einstein Telescope in Europe only marginally increases the rate from
per year to per year (a factor of 1.1
improvement). The addition of an Australian observatory, however, ensures that
at least two observatories are online far more often. When the Cosmic Explorer
km is offline for a major upgrade, the Australian observatory increases
the joint observation rate from per year to
per year (a factor of 82 improvement). When the Einstein
Telescope is offline, the joint observation rate increases from
per year to per year (a factor of 113
improvement). We sketch out the broader science case for a Southern-Hemisphere
gravitational-wave observatory.Comment: v1, 13 pages, 7 figures. Submitted to PRD on August 24 202
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