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Identification of priority populations such as men who have sex with men (MSM) is important in surveillance systems to monitor trends of sexually transmitted infections (STIs). We explored using routinely collected non-behavioural data as a means to establish MSM status in surveillance by assessing anorectal swab as a marker of male-to-male sexual exposure. We used chlamydia testing data from a sexual health clinic, 2007–2012. Men reporting any male sexual partner(s) in the previous 12 months were considered MSM. The dataset was split into development and validation samples to develop a univariate predictive model and assess the model fit. The dataset included 30 358 individual men and 48 554 episodes of STI testing; 45% were among reported MSM and an anorectal swab was performed in 40% of testing episodes. Anorectal swabbing had good diagnostic performance as a marker for MSM status (sensitivity = 87%, specificity = 99%, positive predictive value = 98·6%, negative predictive value = 90·3%). The model showed good fit against the internal validation sample (area under the curve = 0·93). Anorectal swabs are a valid marker of MSM behaviour in surveillance data from sexual health clinics, and they are likely to be particularly useful for monitoring STI trends among MSM with higher risk behaviour.
A procedure is described for testing ice in tension. It incorporates a one-piece lucite mold, two carpeted “Synthane” end-caps and a pair of yokes anti ball joints. Use of the procedure has resulted in a successful test rate greater than 80%.
Although there is robust evidence linking childhood adversities (CAs) and an increased risk for psychotic experiences (PEs), little is known about whether these associations vary across the life-course and whether mental disorders that emerge prior to PEs explain these associations.
We assessed CAs, PEs and DSM-IV mental disorders in 23 998 adults in the WHO World Mental Health Surveys. Discrete-time survival analysis was used to investigate the associations between CAs and PEs, and the influence of mental disorders on these associations using multivariate logistic models.
Exposure to CAs was common, and those who experienced any CAs had increased odds of later PEs [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.9–2.6]. CAs reflecting maladaptive family functioning (MFF), including abuse, neglect, and parent maladjustment, exhibited the strongest associations with PE onset in all life-course stages. Sexual abuse exhibited a strong association with PE onset during childhood (OR 8.5, 95% CI 3.6–20.2), whereas Other CA types were associated with PE onset in adolescence. Associations of other CAs with PEs disappeared in adolescence after adjustment for prior-onset mental disorders. The population attributable risk proportion (PARP) for PEs associated with all CAs was 31% (24% for MFF).
Exposure to CAs is associated with PE onset throughout the life-course, although sexual abuse is most strongly associated with childhood-onset PEs. The presence of mental disorders prior to the onset of PEs does not fully explain these associations. The large PARPs suggest that preventing CAs could lead to a meaningful reduction in PEs in the population.
Nodal metastasis is an important prognostic factor in head and neck squamous cell carcinoma. This study aimed to determine the average nodal basin yield per level of neck dissection, and to investigate if age, gender, body mass index, tumour size, depth of tumour invasion and p16 status influence nodal yield.
A retrospective review of 185 patients with head and neck squamous cell carcinoma generated 240 neck dissection specimens.
The respective mean nodal yields for levels I, II, III, IV and V were 5.27, 9.43, 8.49, 7.43 and 9.02 in non-cutaneous squamous cell carcinoma patients, and 4.2, 7.57, 9.65, 4.33 and 12.29 in cutaneous squamous cell carcinoma patients. Multiple regression analysis revealed that p16-positive patients with mucosal squamous cell carcinoma yielded, on average, 2.4 more nodes than their p16-negative peers (p = 0.04, 95 per cent confidence interval = 0.116 to 4.693). This figure was 3.84 (p = 0.008, 95 per cent confidence interval = 1.070 to 6.605) for p16-positive patients with oral cavity squamous cell carcinoma.
In mucosal squamous cell carcinoma, p16-positive status significantly influenced nodal yield, with the impact being more pronounced in oral cavity squamous cell carcinoma patients.
The Herschel Space Observatory was the fourth cornerstone mission in the European Space Agency (ESA) science programme with excellent broad band imaging capabilities in the sub-mm and far-infrared part of the spectrum. Although the spacecraft finished its observations in 2013, it left a large legacy dataset that is far from having been fully scrutinised and still has a large potential for new scientific discoveries. This is specifically true for the photometric observations of the PACS and SPIRE instruments. Some source catalogues have already been produced by individual observing programs, but there are many observations that risk to remain unexplored. To maximise the science return of the SPIRE and PACS data sets, we are in the process of building the Herschel Point Source Catalogue (HPSC) from all primary and parallel mode observations. Our homogeneous source extraction enables a systematic and unbiased comparison of sensitivity across the different Herschel fields that single programs will generally not be able to provide. The catalogue will be made available online through archives like the Herschel Science Archive (HSA), the Infrared Science Archive (IRSA), and the Strasbourg Astronomical Data Center (CDS).
The Ultra-Fast Flash Observatory (UFFO), which will be launched onboard the
Lomonosov spacecraft, contains two crucial instruments: UFFO Burst
Alert & Trigger Telescope (UBAT) for detection and localization of Gamma-Ray Bursts
(GRBs) and the fast-response Slewing Mirror Telescope (SMT) designed for the observation
of the prompt optical/UV counterparts. Here we discuss the in-space calibrations of the
UBAT detector and SMT telescope. After the launch, the observations of the standard X-ray
sources such as pulsar in Crab nebula will provide data for necessary calibrations of
UBAT. Several standard stars will be used for the photometric calibration of SMT. The
celestial X-ray sources, e.g. X-ray binaries with bright optical sources
in their close angular vicinity will serve for the cross-calibration of UBAT and SMT.
The Ultra-Fast Flash Observatory (UFFO) Pathfinder for Gamma-Ray Bursts (GRBs) consists
of two telescopes. The UFFO Burst Alert & Trigger Telescope (UBAT) handles the
detection and localization of GRBs, and the Slewing Mirror Telescope (SMT) conducts the
measurement of the UV/optical afterglow. UBAT is equipped with an X-ray detector, analog
and digital signal readout electronics that detects X-rays from GRBs and determines the
location. SMT is equipped with a stepping motor and the associated electronics to rotate
the slewing mirror targeting the GRBs identified by UBAT. First the slewing mirror points
to a GRB, then SMT obtains the optical image of the GRB using the intensified CCD and its
readout electronics. The UFFO Data Acquisition system (UDAQ) is responsible for the
overall function and operation of the observatory and the communication with the satellite
main processor. In this paper we present the design and implementation of the electronics
of UBAT and SMT as well as the architecture and implementation of UDAQ.
One of the unexplored domains in the study of gamma-ray bursts (GRBs) is the early time
phase of the optical light curve. We have proposed Ultra-Fast Flash Observatory (UFFO) to
address this question through extraordinary opportunities presented by a series of small
space missions. The UFFO is equipped with a fast-response Slewing Mirror Telescope that
uses a rapidly moving mirror or mirror array to redirect the optical beam rather than
slewing the entire spacecraft or telescope to aim the optical instrument at the GRB
position. The UFFO will probe the early optical rise of GRBs with sub-second response, for
the first time, opening a completely new frontier in GRB and transient studies. Its fast
response measurements of the optical emission of dozens of GRB each year will provide
unique probes of the burst mechanism and test the prospect of GRB as a new standard
candle, potentially opening up the z > 10 universe. We describe the current limit in
early photon measurements, the aspects of early photon physics, our soon-to-be-launched
UFFO-pathfinder mission, and our next planned mission, the UFFO-100.
The Slewing Mirror Telescope (SMT) is the UV/optical telescope of UFFO-pathfinder. The
SMT optical system is a Ritchey-Chrétien (RC) telescope of 100 mm diameter pointed by
means of a gimbal-mounted flat mirror in front of the telescope. The RC telescope has a
17 × 17arcmin2 in Field of View and 4.3 arcsec resolution (full width half
maximum of the point spread function) The beam-steering mirror enables the SMT to access a
35 × 35degree region and point and settle within 1 sec. All mirrors were fabricated to
about 0.02 wavelengths RMS in wave front error (WFE) and 84.7% average reflectivity over
200 nm ~ 650 nm. The RC telescope was aligned to 0.05 wavelengths RMS in WFE (test
wavelength 632.8 nm). In this paper, the technical details of the RC telescope and slewing
mirror system assembly, integration, and testing are given shortly, and performance tests
of the full SMT optical system are reported.
The UFFO (Ultra-Fast Flash Observatory) is a GRB detector on board the Lomonosov
satellite, to be launched in 2013. The GRB trigger is provided by an X-ray detector,
called UBAT (UFFO Burst Alarm & Trigger Telescope), which detects X-rays from the GRB
and then triggers to determine the direction of the GRB and then alerts the Slewing Mirror
Telescope (SMT) to turn in the direction of the GRB and record the optical photon fluxes.
This report details the calibration of the two components: the MAPMTs and the YSO crystals
and simulations of the UBAT. The results shows that this design can observe a GRB within a
field of view of ±35° and can trigger in a time scale as short as 0.2 – 1.0 s
after the appearance of a GRB X-ray spike.
The Ultra-Fast Flash Observatory (UFFO) is a space observatory for optical follow-ups of
gamma ray bursts (GRBs), aiming to explore the first 60 seconds of GRBs optical emission.
UFFO is utilized to catch early optical emissions from GRBs within few sec after trigger
using a Gimbal mirror which redirects the optical path rather than slewing entire
spacecraft. We have developed a 15 cm two-axis Gimbal mirror stage for the UFFO-Pathfinder
which is going to be on board the Lomonosov satellite which is to be launched in 2013. The
stage is designed for fast and accurate motion with given budgets of 3 kg of mass and 3
Watt of power. By employing stepping motors, the slewing mirror can rotate faster than 15
deg/sec so that objects in the UFFO coverage (60 deg × 60 deg) can be targeted in
~1 sec. The obtained targeting resolution is better 2 arcmin using a close-loop
control with high precision rotary encoder. In this presentation, we will discuss details
of design, manufacturing, space qualification tests, as well as performance tests.
The Ultra-Fast Flash Observatory (UFFO) aims to detect the earliest moment of Gamma-Ray
Bursts (GRBs) which is not well known, resulting into the enhancement of GRB mechanism
understanding. The pathfinder mission was proposed to be a scaled-down version of UFFO,
and only contains the UFFO Burst Alert & Trigger Telescope (UBAT) measuring the
X-ray/gamma-ray with the wide-field of view and the Slewing Mirror Telescope (SMT) with a
rapid-response for the UV/optical photons. Once the UBAT detects a GRB candidate with the
position accuracy of 10 arcmin, the SMT steers the UV/optical photons from the candidate
to the telescope by the fast rotatable mirror and provides the early UV/optical photons
measurements with 4 arcsec accuracy. The SMT has a modified Ritchey-Chrètien telescope
with the aperture size of 10 cm diameter including the rotatable mirror and the image
readout by the intensified charge-coupled device. There is a key board called the UFFO
Data Acquisition system (UDAQ) that manages the communication of each telescope and also
of the satellite and the UFFO overall operation. This pathfinder is designed and built
within the limited size and weight of ~20 kg and the low power consumption up to
~30 W. We will discuss the design and performance of the UFFO-pathfinder, and its
integration to the Lomonosov satellite.
The Ultra-Fast Flash Observatory (UFFO) is a space mission to detect the early moments of an explosion from Gamma-ray bursts (GRBs), thus enhancing our understanding of the GRB mechanism. It consists of the UFFO Burst & Trigger telescope (UBAT) for the recognition of GRB positions using hard X-ray from GRBs. It also contains the Slewing Mirror Telescope (SMT) for the fast detection of UV-optical photons from GRBs. It is designed to begin the UV-optical observations in less than a few seconds after the trigger. The UBAT is based on a coded-mask X-ray camera with a wide field of view (FOV) and is composed of the coded mask, a hopper and a detector module. The SMT has a fast rotatable mirror which allows a fast UV-optical detection after the trigger. The telescope is a modified Ritchey-Chrétien telescope with the aperture size of 10 cm diameter, and an image intensifier readout by CCD. The UFFO pathfinder is scheduled to launch into orbit on 2012 June by the Lomonosov spacecraft. It is a scaled-down version of UFFO in order to make the first systematic study of early UV/optical light curves, including the rise phase of GRBs. We expect UBAT to trigger ~44 GRBs/yr and expect SMT to detect ~10 GRBs/yr.
The elastic constants of the L12-type ordered nickel-based intermetallics Ni3X (X = Mn, Al, Ga, Si, Ge), have been calculated by means of ab initio total-energy electronic structurecalculations based on the full-potential linear-muffin-tin-orbital (FLMTO) method. Theorigins in the electronic structure of the variation of the elastic constants, bulk and shearmoduli are investigated across the series, and the effects of the anisotropy of bonding chargedensity on the shear anisotropy factor and the degree of ductility is discussed.
We report an investigation into the mechanism responsible for the optical limiting behavior in multiwalled carbon nanotubes. We conducted energy-dependent transmission measurements, picosecond time-resolved pump-probe, and nonlinear scattering experiments at 532-nm wavelength on multiwalled carbon nanotube suspension. For comparison, C60-toluene solution and carbon black suspension were also studied in the same experiments. The similarities that we observed between the multiwalled carbon nanotubes and carbon black suspension suggest that nonlinear scattering, which is known to be responsible for the limiting action in carbon black suspension, should play an important role in the limiting effect in multiwalled carbon nanotubes.
Polycrystalline Si (poly-Si) waveguides offer design flexibility and multilayered structures in Si-integrated photonic devices. However, as-deposited poly-Si surfaces are rough compared with single-crystalline Si, and a rough surface causes significant waveguide scattering loss at the surface. In this study, surface smoothing of poly-Si waveguides with a gas-cluster ion beam (GCIB) was demonstrated as a new smoothing technique. As the GCIB process is a directional ion-beam process, in principle it can be applied not only to plane surfaces but also to three-dimensional or non-flat structures, such as waveguide ridges.
The initial average roughness of as-deposited poly-Si films (625°C, 1 μm thick) ranged from 15 nm to 22 nm, and the grain sizes were distributed from 0.2 to 0.4μm. This rough surface was dramatically smoothed to a roughness of 1.5 nm by Ar cluster ion irradiation. From the relation between the sputtered depth and the surface roughness, the sputtered depth must be greater than the height difference of the roughness (peak-to-valley) to obtain smooth surfaces. Optical transmission losses at λ =1.54 μm were measured using cutback measurement from samples before and after the smoothing by GCIB. After surface smoothing with GCIB, the optical loss decreased from 85 dB/cm to 54 dB/cm.
Amorphous Fe80B20 alloy films with a large quantity of plastics (polymethyl methacrylate: PMMA) are prepared using a combined technique of electrochemical plating and spin coating. The embedding of amorphous alloys into PMMA plastics is expected to reduce the effective conductivities of alloy films, and hence to improve their magnetomechanical coupling coefficients at high frequency by reducing effective eddy-current losses. Preparation conditions for obtaining Fe100−XBX (X=20±5at%) films with amorphous structure are determined, and the composite films are formed in accordance with the plating conditions. The resultant composite films are studied by examining their surface states and magnetic properties.
At JPL, it is our desire to fabricate thermoelectric micro-devices for power generation and cooling applications using an electrochemical deposition (ECD) technique. We believe that the performance of our current micro-device developed is limited by the properties of the ECD materials. Therefore, the objective of this study is to develop ECD methods for obtaining n-type Bi2Te3 and p-type Bi2-xSbxTe3 thermoelectric materials with near bulk properties, as well as optimizing morphology and transport properties. The films of Bi2Te3 and Bi2-xSbxTe3 were initially obtained under various ECD conditions. Seebeck coefficients and transport properties were then measured along the direction parallel to the substrates before and after annealing at 250°C for 2hrs. From the data obtained, ECD n-Bi2Te3 material can achieve a high Seebeck coefficient (-189 μV/K) when it is deposited at –200 mV vs. SCE. The in-plane resistivity, in-plane mobility, and carrier concentration are 3.0 mohm-cm, 31 cm2 V−1 S−1, and 6.79 × 1019 cm−3, respectively. As for the p-type Bi2-xSbxTe3, it is possible to achieve a high Seebeck coefficient (+295 μV/K) when it is deposited at 0.3 mA/cm2. The in-plane resistivity, in-plane mobility, and carrier concentration are 9.8374 mohm-cm, 66.58 cm2 V−1 S−1, and 9.54 × 1018 cm−3, respectively. From the results of our preliminary study, we have found the conditions for depositing high quality Bi2Te3 and Bi2-xSbxTe3 materials with thermoelectric properties comparable to those of their state-of-the-art bulk samples.