To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
Excavations at several locations in Verteba Cave have uncovered a large amount of human skeletal remains in association with faunal bones and Tripolye material culture. We aim to establish radiocarbon (14C) dates for eight sites and to evaluate whether these deposits are singular events, or slow accumulations over time. 14C measurements, along with stable carbon and nitrogen isotope data from human and faunal remains, were collected from 18 specimens. Stable isotope values were used to evaluate human and animal diet, and whether freshwater reservoir effects offset measured dates. We found diets of the sampled species had limited to no influence from freshwater resources. Human diet appears to be dominated by terrestrial plants and herbivores. Four new sites were identified as Eneolithic. Comparisons of dates from top and bottom strata for two sites (7 and 20) reveal coeval dates, and we suggest that these deposits represent discrete events rather than slow continuous use. Lastly, we identified dates from the Mesolithic (8490±45 BP, 8765±30 BP), Iron Age (2505±20 BP), Slavic state era (1315±25 BP), and Medieval Period (585±15 BP), demonstrating periodic use of the cave by humans prior to and after the Eneolithic.
The SPICA mid- and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimised detectors, and wide instantaneous bandwidth throughout the mid- and far-infrared. The spectroscopic, imaging, and polarimetric observations that SPICA will be able to collect will help in clarifying the complex physical mechanisms which underlie the baryon cycle of galaxies. In particular, (i) the access to a large suite of atomic and ionic fine-structure lines for large samples of galaxies will shed light on the origin of the observed spread in star-formation rates within and between galaxies, (ii) observations of HD rotational lines (out to ~10 Mpc) and fine structure lines such as [C ii] 158 μm (out to ~100 Mpc) will clarify the main reservoirs of interstellar matter in galaxies, including phases where CO does not emit, (iii) far-infrared spectroscopy of dust and ice features will address uncertainties in the mass and composition of dust in galaxies, and the contributions of supernovae to the interstellar dust budget will be quantified by photometry and monitoring of supernova remnants in nearby galaxies, (iv) observations of far-infrared cooling lines such as [O i] 63 μm from star-forming molecular clouds in our Galaxy will evaluate the importance of shocks to dissipate turbulent energy. The paper concludes with requirements for the telescope and instruments, and recommendations for the observing strategy.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.
The physical processes driving the chemical evolution of galaxies in the last ~ 11Gyr cannot be understood without directly probing the dust-obscured phase of star-forming galaxies and active galactic nuclei. This phase, hidden to optical tracers, represents the bulk of the star formation and black hole accretion activity in galaxies at 1 < z < 3. Spectroscopic observations with a cryogenic infrared observatory like SPICA, will be sensitive enough to peer through the dust-obscured regions of galaxies and access the rest-frame mid- to far-infrared range in galaxies at high-z. This wavelength range contains a unique suite of spectral lines and dust features that serve as proxies for the abundances of heavy elements and the dust composition, providing tracers with a feeble response to both extinction and temperature. In this work, we investigate how SPICA observations could be exploited to understand key aspects in the chemical evolution of galaxies: the assembly of nearby galaxies based on the spatial distribution of heavy element abundances, the global content of metals in galaxies reaching the knee of the luminosity function up to z ~ 3, and the dust composition of galaxies at high-z. Possible synergies with facilities available in the late 2020s are also discussed.
Childhood maltreatment (CM) has consistently been linked with adverse outcomes including substance use disorders and adult sexual revictimization. Adult sexual victimization itself has been linked with psychopathology but has predominately been studied in women. The current investigation examines the impact of CM and co-occurring psychopathology on adult sexual victimization in men and women, replicating findings in three distinct samples.
We investigated the association between continuous CM factor scores and adult sexual victimization in the Childhood Trauma Study (CTS) sample (N = 2564). We also examined the unique relationship between childhood sexual abuse (CSA) and adult sexual victimization while adjusting for co-occurring substance dependence and psychopathology. We replicated these analyses in two additional samples: the Comorbidity and Trauma Study (CATS; N = 1981) and the Australian Twin-Family Study of Alcohol Use Disorders (OZ-ALC; N = 1537).
Analyses revealed a significant association with CM factor scores and adult sexual victimization for both men and women across all three samples. The CSA factor score was strongly associated with adult sexual victimization after adjusting for substance dependence and psychopathology; higher odds ratios were observed in men (than women) consistently across the three samples.
A continuous measure of CSA is independently associated with adult sexual trauma risk across samples in models that included commonly associated substance dependence and psychopathology as covariates. The strength of the association between this CSA measure and adult sexual victimization is higher in magnitude for men than women, pointing to the need for further investigation of sexual victimization in male community samples.
Genetic influences contribute significantly to co-morbidity between conduct disorder and substance use disorders. Estimating the extent of overlap can assist in the development of phenotypes for genomic analyses.
Multivariate quantitative genetic analyses were conducted using data from 9577 individuals, including 3982 complete twin pairs and 1613 individuals whose co-twin was not interviewed (aged 24–37 years) from two Australian twin samples. Analyses examined the genetic correlation between alcohol dependence, nicotine dependence and cannabis abuse/dependence and the extent to which the correlations were attributable to genetic influences shared with conduct disorder.
Additive genetic (a2 = 0.48–0.65) and non-shared environmental factors explained variance in substance use disorders. Familial effects on conduct disorder were due to additive genetic (a2 = 0.39) and shared environmental (c2 = 0.15) factors. All substance use disorders were influenced by shared genetic factors (rg = 0.38–0.56), with all genetic overlap between substances attributable to genetic influences shared with conduct disorder. Genes influencing individual substance use disorders were also significant, explaining 40–73% of the genetic variance per substance.
Among substance users in this sample, the well-documented clinical co-morbidity between conduct disorder and substance use disorders is primarily attributable to shared genetic liability. Interventions targeted at generally reducing deviant behaviors may address the risk posed by this shared genetic liability. However, there is also evidence for genetic and environmental influences specific to each substance. The identification of these substance-specific risk factors (as well as potential protective factors) is critical to the future development of targeted treatment protocols.
Comparison of the ISM properties of a wide range of metal poor galaxies with normal metal-rich galaxies reveals striking differences. We find that the combination of the low dust abundance and the active star formation results in a very porous ISM filled with hard photons, heating the dust in dwarf galaxies to overall higher temperatures than their metal-rich counterparts. This results in photodissociation of molecular clouds to greater depths, leaving relatively large PDR envelopes and difficult-to-detect CO cores. From detailed modeling of the low-metallicity ISM, we find significant fractions of CO-dark H2 - a reservoir of molecular gas not traced by CO, but present in the [CII] and [CI]-emitting envelopes. Self-consistent analyses of the neutral and ionized gas diagnostics along with the dust SED is the necessary way forward in uncovering the multiphase structure of galaxies.
Anaplastic thyroid carcinoma is rare but carries a poor prognosis. Anaplastic thyroid carcinoma leads to tracheal compression, airway compromise and eventually death. Airway compromise, a particularly distressing symptom, can be palliated with tracheal stenting.
A retrospective case note analysis was conducted of patients diagnosed with anaplastic thyroid carcinoma between July 2003 and July 2013.
Twelve patients with anaplastic thyroid carcinoma were identified. Four patients underwent palliative tracheal stenting. Three patients had no dyspnoea at the time of stenting. Two stented patients subsequently developed dyspnoea secondary to stent migration; this was managed successfully with stent exchange. The other stented patient remained asymptomatic with regards to dyspnoea. All non-stented patients died with or from airway compromise.
Tracheal stenting is a relatively safe and effective method for palliation of distressing airway symptoms in patients with anaplastic thyroid carcinoma. Early prophylactic tracheal stenting in anaplastic thyroid carcinoma may be an effective option to prevent development of airway compromise as the disease progresses.
Bioarchaeological studies have found that, in general, the adoption of agriculture is associated with deteriorating oral health, most frequently manifested as an increase in the prevalence of dental caries. However, compared to other regions of the world, bioarchaeological studies focusing on prehistoric Europe have produced more variable results, with different populations experiencing deteriorations, improvements, and stasis in oral health. This study assesses the oral health of individuals of the Tripolye culture buried in Verteba Cave, Ukraine, within the context of the transition to agriculture in Eastern Europe. We compare the rates of dental caries between Tripolye farmers with earlier hunter-fisher-gatherers from Ukraine. The Tripolye were found to have carious lesions on 9.5 per cent of teeth, while the hunter-fisher-gatherers were found to be universally free of carious lesions. A Fisher's exact test demonstrates that this difference is statistically significant, supporting the model that the transition to agriculture was detrimental to oral health in prehistoric Ukraine. This could be related to the manner in which grain was processed by the Tripolye and the needs of their relatively population-dense society.
Anorexia nervosa (AN) is a serious disorder incurring high costs due to hospitalization. International treatments vary, with prolonged hospitalizations in Europe and shorter hospitalizations in the USA. Uncontrolled studies suggest that longer initial hospitalizations that normalize weight produce better outcomes and fewer admissions than shorter hospitalizations with lower discharge weights. This study aimed to compare the effectiveness of hospitalization for weight restoration (WR) to medical stabilization (MS) in adolescent AN.
We performed a randomized controlled trial (RCT) with 82 adolescents, aged 12–18 years, with a DSM-IV diagnosis of AN and medical instability, admitted to two pediatric units in Australia. Participants were randomized to shorter hospitalization for MS or longer hospitalization for WR to 90% expected body weight (EBW) for gender, age and height, both followed by 20 sessions of out-patient, manualized family-based treatment (FBT).
The primary outcome was the number of hospital days, following initial admission, at the 12-month follow-up. Secondary outcomes were the total number of hospital days used up to 12 months and full remission, defined as healthy weight (>95% EBW) and a global Eating Disorder Examination (EDE) score within 1 standard deviation (s.d.) of published means. There was no significant difference between groups in hospital days following initial admission. There were significantly more total hospital days used and post-protocol FBT sessions in the WR group. There were no moderators of primary outcome but participants with higher eating psychopathology and compulsive features reported better clinical outcomes in the MS group.
Outcomes are similar with hospitalizations for MS or WR when combined with FBT. Cost savings would result from combining shorter hospitalization with FBT.
The aim of the present study was to determine whether age and sex influence both the status and incorporation of EPA and DHA into blood plasma, cells and tissues. The study was a double-blind, randomised, controlled intervention trial, providing EPA plus DHA equivalent to 0, 1, 2 or 4 portions of oily fish per week for 12 months. The participants were stratified by age and sex. A linear regression model was used to analyse baseline outcomes, with covariates for age or sex groups and by adjusting for BMI. The change in outcomes from baseline to 12 months was analysed with additional adjustment for treatment and average compliance. Fatty acid profiles in plasma phosphatidylcholine, cholesteryl esters, NEFA and TAG, mononuclear cells (MNC), erythrocyte membranes, platelets, buccal cells (BU) and adipose tissue (AT) were determined. At baseline, EPA concentrations in plasma NEFA and DHA concentrations in MNC, BU and AT were higher in females than in males (all P< 0·05). The concentrations of EPA in AT (P= 0·003) and those of DHA in plasma TAG (P< 0·01) and AT (P< 0·001) were higher with increasing age. Following 12-month supplementation with EPA plus DHA, adjusted mean difference for change in EPA concentrations in plasma TAG was significantly higher in females than in males (P< 0·05) and was greater with increasing age (P= 0·02). Adjusted mean difference for change in DHA concentrations in AT was significantly smaller with increasing age (P= 0·02). Although small differences in incorporation with age and sex were identified, these were not of sufficient magnitude to warrant a move away from population-level diet recommendations for n-3 PUFA.
DSM-IV specifies a hierarchal diagnostic structure such that an oppositional defiant disorder (ODD) diagnosis is applied only if criteria are not met for conduct disorder (CD). Genetic studies of ODD and CD support a combination of shared genetic and environmental influences but largely ignore the imposed diagnostic structure.
We examined whether ODD and CD share an underlying etiology while accounting for DSM-IV diagnostic specifications. Data from 1446 female twin pairs, aged 11–19 years, were fitted to two-stage models adhering to the DSM-IV diagnostic hierarchy.
The models suggested that DSM-IV ODD–CD covariation is attributed largely to shared genetic influences.
This is the first study, to our knowledge, to examine genetic and environmental overlap among these disorders while maintaining a DSM-IV hierarchical structure. The findings reflect primarily shared genetic influences and specific (i.e. uncorrelated) shared/familial environmental effects on these DSM-IV-defined behaviors. These results have implications for how best to define CD and ODD for future genetically informed analyses.
We present Herschel-SPIRE imaging spectroscopy (194-671 μm) of the bright starburst galaxy M82. We use RADEX and a Bayesian Likelihood Analysis to simultaneously model the temperature, density, column density, and filling factor of both the cool and warm components of molecular gas traced by the entire CO ladder up to J=13-12. The high-J lines observed by SPIRE trace much warmer gas (~500 K) than those observable from the ground. The addition of 13CO (and [C I]) is new and indicates that [C I] may be tracing different gas than 12CO. At such a high temperature, cooling is dominated by molecular hydrogen; we conclude with a discussion on the possible excitation processes in this warm component. Photon-dominated region (PDR) models require significantly higher densities than those indicated by our Bayesian likelihood analysis in order to explain the high-J CO line ratios, though cosmic-ray enhanced PDR models can do a better job reproducing the emission at lower densities. Shocks and turbulent heating are likely required to explain the bright high-J emission.
Initiation of cannabis use typically follows alcohol use, but the reverse order does occur and is more common for African-Americans (AAs) than European-Americans (EAs). The aim of this study was to test for differences in the order of initiation of cannabis and alcohol use between AA and EA women and to determine whether order and ethnicity contribute independently to risk for rapid progression to cannabis-related problems.
Data were drawn from structured psychiatric interviews of 4102 women (mean age = 21.6 years), 3787 from an all-female twin study and 315 from a high-risk family study; 18.1% self-identified as AA, 81.9% as EA. Ethnicity and order of initiation of cannabis and alcohol use were modeled as predictors of transition time from first use to onset of cannabis use disorder symptom(s) using Cox proportional hazards regression analyses.
AA women were nearly three times as likely as EA women to initiate cannabis use before alcohol use. Using cannabis before alcohol [hazard ratio (HR) 1.44, 95% confidence interval (CI) 1.08–1.93] and AA ethnicity (HR 1.59, 95% CI 1.13–2.24) were both associated with rapid progression from first use to cannabis symptom onset even after accounting for age at initiation and psychiatric risk factors.
The findings indicate that AA women are at greater risk for rapid development of cannabis-related problems than EA women and that this risk is even higher when cannabis use is initiated before alcohol use. Prevention programs should be tailored to the various patterns of cannabis use and relative contributions of risk factors to the development of cannabis-related problems in different ethnic groups.
Familial influences on remission from alcohol use disorder (AUD) have been studied using family history of AUD rather than family history of remission. The current study used a remission phenotype in a twin sample to examine the relative contributions of genetic and environmental influences to remission.
The sample comprised 6183 twins with an average age of 30 years from the Australian Twin Registry. Lifetime history of alcohol abuse and dependence symptoms and symptom recency were assessed with a structured telephone interview. AUD was defined broadly and narrowly as history of two or more or three or more abuse or dependence symptoms. Remission was defined as absence of symptoms at time of interview among individuals with lifetime AUD. Standard bivariate genetic analyses were conducted to derive estimates of genetic and environmental influences on AUD and remission.
Environmental influences alone accounted for remission in males and for 89% of influences on remission in females, with 11% due to genetic influences shared with AUD, which decreased the likelihood of remission. For women, more than 80% of influences on remission were distinct from influences on AUD, and environmental influences were from individual experiences only. For men, just over 50% of influences on remission were distinct from those on AUD, and the influence of environments shared with the co-twin were substantial. The results for the broad and narrow phenotypes were similar.
The current study establishes young adult remission as a phenotype distinct from AUD and highlights the importance of environmental influences on remission.
Properties of radiatively cooled supersonic plasma jets formed by ablation of thin Al
foils driven by 1.4 MA, 250 ns current pulse are presented. The jets are highly collimated
with half-opening angles of ~2°. Measurements of the flow velocity (~60
km/s) and plasma temperature (~15 eV) in the jet with Thomson scattering diagnostic
give internal Mach number of M ~ 3, suggesting additional collimation of the jet by
toroidal magnetic fields.