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Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
Indium tin oxide (ITO) has become a very useful plasmonic and nonlinear optical material because of its highly tunable electrical and optical properties and strong optical nonlinearity. In this work, the authors conducted detailed fabrication process studies by using high-temperature reactive sputtering to finely tune the optical properties of ITO thin films, particularly the epsilon-near-zero (ENZ) wavelength in the near and mid-IR spectrum. Sputtered ITO thin films are characterized by using spectroscopic ellipsometry, surface profilometry, Hall measurements, and 4-point probe testing. Additionally, the effect of post-deposition annealing of ITO films is also investigated.
The scarcity of Romano-British human remains from north-west England has hindered understanding of burial practice in this region. Here, we report on the excavation of human and non-human animal remains1 and material culture from Dog Hole Cave, Haverbrack. Foetal and neonatal infants had been interred alongside a horse burial and puppies, lambs, calves and piglets in the very latest Iron Age to early Romano-British period, while the mid- to late Roman period is characterised by burials of older individuals with copper-alloy jewellery and beads. This material culture is more characteristic of urban sites, while isotope analysis indicates that the later individuals were largely from the local area. We discuss these results in terms of burial ritual in Cumbria and rural acculturation. Supplementary material is available online (https://doi.org/10.1017/S0068113X20000136), and contains further information about the site and excavations, small finds, zooarchaeology, human osteology, site taphonomy, the palaeoenvironment, isotope methods and analysis, and finds listed in Benson and Bland 1963.
Propagating inhomogeneous electromagnetic waves called surface plasmon polaritons (SPPs) can be excited by free-space beams on corrugated conducting surfaces at resonance angles determined by corrugation period, permittivity, and optical frequency. SPPs are coupled to and co-propagate with surface charge displacements. Complete electrical isolation of individual conducting corrugations prevents the charge displacement necessary to sustain an SPP, such that excitation resonances of traveling SPPs are absent. However, SPPs can be excited via electric induction if a smooth conducting surface exists below and nearby the isolated conducting corrugations. The dependence of SPP excitation resonances on that separation is experimentally investigated here at long-wave infrared wavelengths. We find that excitation resonances for traveling SPPs broaden and disappear as the dielectric’s physical thickness is increased beyond ~1% of the free-space wavelength. The resonance line width increases with refractive index and optical thickness of the dielectric.
The science of studying diamond inclusions for understanding Earth history has developed significantly over the past decades, with new instrumentation and techniques applied to diamond sample archives revealing the stories contained within diamond inclusions. This chapter reviews what diamonds can tell us about the deep carbon cycle over the course of Earth’s history. It reviews how the geochemistry of diamonds and their inclusions inform us about the deep carbon cycle, the origin of the diamonds in Earth’s mantle, and the evolution of diamonds through time.
Cognitive impairment is strongly linked with persistent disability in people with mood disorders, but the factors that explain cognitive impairment in this population are unclear.
Aims
To estimate the total effect of (a) bipolar disorder and (b) major depression on cognitive function, and the magnitude of the effect that is explained by potentially modifiable intermediate factors.
Method
Cross-sectional study using baseline data from the UK Biobank cohort. Participants were categorised as having bipolar disorder (n = 2709), major depression (n = 50 975) or no mood disorder (n = 102 931 and n = 105 284). The outcomes were computerised tests of reasoning, reaction time and memory. The potential mediators were cardiometabolic disease and psychotropic medication. Analyses were informed by graphical methods and controlled for confounding using regression, propensity score-based methods and G-computation.
Results
Group differences of small magnitude were found on a visuospatial memory test. Z-score differences for the bipolar disorder group were in the range −0.23 to −0.17 (95% CI −0.39 to −0.03) across different estimation methods, and for the major depression group they were approximately −0.07 (95% CI −0.10 to −0.03). One-quarter of the effect was mediated via psychotropic medication in the bipolar disorder group (−0.05; 95% CI −0.09 to −0.01). No evidence was found for mediation via cardiometabolic disease.
Conclusions
In a large community-based sample in middle to early old age, bipolar disorder and depression were associated with lower visuospatial memory performance, in part potentially due to psychotropic medication use. Mood disorders and their treatments will have increasing importance for population cognitive health as the proportion of older adults continues to grow.
Declaration of interest
I.J.D. is a UK Biobank participant. J.P.P. is a member of the UK Biobank Steering Committee.
Metal–insulator–metal (MIM) resonant absorbers comprise a conducting ground plane, a dielectric of thickness t, and thin separated metal top-surface structures of dimension l. The fundamental resonance wavelength is predicted by an analytic standing-wave model based on t, l, and the dielectric refractive index spectrum. For the dielectrics SiO2, AlN, and TiO2, values for l of a few microns give fundamental resonances in the 8-12 μm long-wave infrared (LWIR) wavelength region. Agreement with theory is better for t/l exceeding 0.1. Harmonics at shorter wavelengths were already known, but we show that there are additional resonances in the far-infrared 20 - 50 μm wavelength range in MIM structures designed to have LWIR fundamental resonances. These new resonances are consistent with the model if far-IR dispersion features in the index spectrum are considered. LWIR fundamental absorptions are experimentally shown to be optimized for a ratio t/l of 0.1 to 0.3 for SiO2- and AlN-based MIM absorbers, respectively, with TiO2-based MIM optimized at an intermediate ratio.
Metal–insulator–metal (MIM) resonant absorbers comprise a conducting ground plane, a thin dielectric, and thin separated metal top-surface structures. The dielectric SiO2 strongly absorbs near 9 µm wavelength and has correspondingly strong long-wave-infrared (LWIR) dispersion for the refractive index. This dispersion results in multiple absorption resonances spanning the LWIR, which can enhance broad-band sensitivity for LWIR bolometers. Similar considerations apply to silicon nitride Si3N4. TiO2 and AlN have comparatively low dispersion and give simple single LWIR resonances. These dispersion-dependent features for infrared MIM devices are demonstrated by experiment, electrodynamic simulation, and an analytic model based on standing waves.
OBJECTIVES/SPECIFIC AIMS: Patients with locally advanced pancreatic cancer typically have poor outcomes, with a median survival of ~16 months. Novel methods to improve local control are needed. Nab-paclitaxel (abraxane) has shown efficacy in pancreatic cancer and is FDA approved for metastatic disease in combination with gemcitabine. Nab-paclitaxel is also a promising radiosensitizer based on laboratory studies, but it has never been clinically tested with definitive radiotherapy for locally advanced disease. METHODS/STUDY POPULATION: We performed a phase 1 study using a 3+3 dose-escalation strategy to determine the safety and tolerability of dose escalated nab-paclitaxel with fractionated radiotherapy for patients with unresectable or borderline resectable pancreatic cancer. Following induction chemotherapy with 2 cycles of nab-paclitaxel and gemcitabine, patients were treated with weekly nab-paclitaxel and daily radiotherapy to a dose of 52.5 Gy in 25 fractions. Final dose-limiting toxicity (DLT) determination was performed at day 65 after the start of radiotherapy. RESULTS/ANTICIPATED RESULTS: Nine patients received nab-paclitaxel at a dose level of either 100 mg/m2 (n=3) or 125 mg/m2 (n=6). One DLT (grade 3 neuropathy) was observed in a patient who received 125 mg/m2 of nab-paclitaxel. Other grade 3 toxicities included fatigue (11%), anemia (11%), and neutropenia (11%). No grade 4 toxicities were observed. With a median follow-up of 8 months (range 5–28 months), median survival was 19 months and median progression-free survival was 10 months. Following chemoradiation, 3 patients underwent surgical resection, all with negative margins and limited tumor viability. Of the 3 patients, 2 initially had borderline resectable tumors and 1 had an unresectable tumor. Tumor (SMAD-4, Caveolin-1) and peripheral (circulating tumor cells and microvesicles) biomarkers were collected and are being analyzed. DISCUSSION/SIGNIFICANCE OF IMPACT: The combination of fractionated radiation and weekly nab-paclitaxel was safe and well tolerated. This regimen represents a potentially promising therapy for patients with unresectable and borderline resectable pancreatic cancer and warrants further investigation.
Vanadium Oxide has application to infrared bolometers due to high temperature coefficient of resistivity (TCR). It has attracted interest for switchable plasmonic devices due to its metal to insulator transition near room temperature. We report here the properties of vanadium oxide deposited by an aqueous spray process. The films have a ropy surface morphology with ∼70 nm surface roughness. The polycrystalline phase depends on annealing conditions. The films have TCR of ∼2%/deg, which compares well with sputtered films. Only weak evidence is found for an insulator-metal phase transition in these films.
Ternary lead chalcogenides, such as PbSxSe1-x, offer the possibility of room-temperature infrared detection with engineered cut-off wavelengths within the important 3-5 micron mid-wave infrared (MWIR) wavelength range. We present growth and characterization of aqueous spray-deposited thin films of PbSSe. Complexing agents in the aqueous medium suppress unwanted homogeneous reactions so that growth occurs only by the heterogeneous reaction on the hydrophilic substrate. The strongly-adherent films are smooth with a mirror-like finish. The films comprise densely packed grains with tens of nm dimensions and a total film thickness of ∼400-500 nm. Measured optical constants reveal absorption out to at least 4.5 μm wavelength and a ∼0.3 eV bandgap intermediate between those of PbS and PbSe. The semiconducting films are p-type with resistivity ∼1 and 85 Ohm-cm at 300 and 80 K, respectively. Sharp x-ray diffraction peaks identify the films as Clausthalite-Galena solid-state solution with a lattice constant that indicates an even mixture of PbS and PbSe. The photoconductive response is observed at both nitrogen and room temperature up to at least 2 kHz chopping frequency.
Self-assembled TiO2 films deposited by aqueous-spray deposition were investigated to evaluate morphology, crystalline phase, and infrared optical constants. The Anatase nano-crystalline film had ∼10 nm characteristic surface roughness sparsely punctuated by defects of not more than 200 nm amplitude. The film is highly transparent throughout the visible to wavelengths of 12 μm. The indirect band gap was determined to be 3.2 eV. Important for long-wave infrared applications is that dispersion in this region is weak compared with the more commonly used dielectric SiO2 for planar structures. An example application to a metal-insulator-metal resonant absorber is presented. The low-cost, large-area, atmospheric-pressure, chemical spray deposition method allows conformal fabrication on flexible substrates for long-wave infrared photonics.
Ira Aldridge -- a black New Yorker -- was one of nineteenth-century Europe's greatest actors. He performed abroad for forty-three years, winning more awards, honors, and official decorations than any of his professional peers. Billed as the "African Roscius," Aldridge developed a repertoire initially consisting of Shakespeare's Othello, melodramas about slavery, and farces that drew on his ability to sing and dance. By the time he began touring in Europe he was principally a Shakespearean actor, playing such classic characters as Shylock, Macbeth, Richard III, and King Lear. Although his frequent public appearances made him the most visible black man in the world by mid-nineteenth century, today Aldridge tends to be a forgotten figure, seldom mentioned in histories of British and European theater. This collection restores the luster to Aldridge's reputation by examining his extraordinary achievements against all odds. The early essays offer biographical information, while later essays examine his critical and popular reception throughout the world. Taken together, these diverse approaches to Aldridge offer a fuller understanding and heightened appreciation of a remarkable man who had an exceptionally interesting life and a spectacular career. Contributors: Cyril Bruyn Andrews, Nikola Batusic, Philip A. Bell, Keith Byerman, Ruth M. Cowhig, Nicholas M. Evans, Joost Groeneboer, Ann Marie Koller, Joyce Green MacDonald, Herbert Marshall, James J. Napier, Krzysztof Sawala, Gunner Sjögren, James McCune Smith, Hazel Waters, and Stanley B. Winters.
Bernth Lindfors is Professor Emeritus of English and African literatures at The University of Texas at Austin.
The absorption of radio waves propagating through naturally occurring waters varies greatly with the electrical conductivity. Glacier melt water is very transparent and the attenuation by melt water layers is due to reflexion of power, whereas the attenuation of sea-water layers is due to absorption. The attenuation of soaked firn is usually prohibitive if the liquid is brine but it should not be a serious obstacle to radio echo strength if the liquid is rain-water or melt water. However, the magnitude of the scattered power can become greater than that from continuous (bedrock) reflectors if the size of the irregularities in the medium is large (approaching the radio wavelength in ice). Echo power formulae show that ice lenses may have the most serious effect and that low radio frequencies will be necessary to combat this.
Insects in the fossil record are generally preserved in lacustrine shales or in amber. For those in lacustrine shales, preservation is usually via keroginization or mineralization. Given the extended period of microbial decay required to generate ions for mineralization, there is a predicted inherent bias toward lower preservation quality for this pathway by most taphonomic indices compared with keroginization. This study tests this hypothesis by comparing multiple measures of preservation quality between sites with similar sedimentology in the Eocene Green River Formation of Colorado. Here, insects are either mineralized in iron oxides (likely after pyrite) at the Paleoburn site or keroginized at the Anvil Points site.
Generally, the prediction that keroginization preserves soft-bodied fossils with higher preservational quality than mineralization is affirmed, but with some caveats. Beetles, known for their robust cuticles, are proportionately more abundant at the Paleoburn site, but eight of the nine orders recorded are shared between sites. As predicted, insects show lower preservation fidelity at the Paleoburn site, but they also show higher degrees of disarticulation. This second bias should be acquired primarily during the biostratinomy stage, and not early diagenesis. Nonetheless, higher-energy biostratinomic conditions may be compatible with taphonomic conditions that promote mineralization over keroginization.
Comparing the inherent taphonomic bias of different preservation pathways is often difficult, since fossil deposits may be preserved millions of years or thousands of kilometers apart. By studying two different preservation pathways of insects within the same formation, we can affirm that keroginization does indeed preserve recalcitrant organic matter with higher quality than pyritization or iron-oxide mineralization. Additionally, some guidelines can be proposed concerning the body parts and taxa that can be compared, and for what purpose, when contrasting mineralized and keroginized soft-bodied deposits.
Palladium germanide thin films were investigated for infrared plasmonic applications. Palladium thin films were deposited onto amorphous germanium thin films and subsequently annealed at a range of temperatures. X-ray diffraction was used to identify stoichiometry, and Scanning Electron Micrographs, along with Energy Dispersive Spectroscopy (EDS) was used to characterize composition and film quality. Resistivity was also measured for analysis. Complex permittivity spectra were measured from 0.3 to 15 µm using IR ellipsometry. From this, surface plasmon polariton (SPP) characteristics such as propagation length and mode confinement were calculated and used to determine appropriate spectral windows for plasmonic applications with respect to film characteristics. Films were evaluated for use with on-chip plasmonic components.
The relative contribution of demographic, lifestyle and medication factors to the association between affective disorders and cardiometabolic diseases is poorly understood.
Aims
To assess the relationship between cardiometabolic disease and features of depresion and bipolar disorder within a large population sample.
Method
Cross-sectional study of 145 991 UK Biobank participants: multivariate analyses of associations between features of depression or bipolar disorder and five cardiometabolic outcomes, adjusting for confounding factors.
Results
There were significant associations between mood disorder features and ‘any cardiovascular disease’ (depression odds ratio (OR) = 1.15, 95% CI 1.12–1.19; bipolar OR = 1.28, 95% CI 1.14–1.43) and with hypertension (depression OR = 1.15, 95% CI 1.13–1.18; bipolar OR = 1.26, 95% CI 1.12–1.42). Individuals with features of mood disorder taking psychotropic medication were significantly more likely than controls not on psychotropics to report myocardial infarction (depression OR = 1.47, 95% CI 1.24–1.73; bipolar OR = 2.23, 95% CI 1.53–3.57) and stroke (depression OR = 2.46, 95% CI 2.10–2.80; bipolar OR = 2.31, 95% CI 1.39–3.85).
Conclusions
Associations between features of depression or bipolar disorder and cardiovascular disease outcomes were statistically independent of demographic, lifestyle and medication confounders. Psychotropic medication may also be a risk factor for cardiometabolic disease in individuals without a clear history of mood disorder.