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Abstract: The COS Legacy Archive Spectroscopic SurveY (CLASSY) is designed to provide the community with a spectral atlas of 45 nearby star-forming galaxies that were chosen to cover similar properties to those seen at high z (z > 6). The prime high-level science product of CLASSY is accurately coadded UV spectra, ranging from ∼1000 to 2000 Å, derived from a combination of archival and new data obtained with HST’s Cosmic Origins Spectrograph (COS). This paper details the multistage technical processes of creating this prime data product and the methodologies involved in extracting, reducing, aligning, and coadding far-ultraviolet and near-ultraviolet (NUV) spectra. We provide guidelines on how to successfully utilize COS observations of extended sources, despite COS being optimized for point sources, and best-practice recommendations for the coaddition of UV spectra in general. Moreover, we discuss the effects of our reduction and coaddition techniques in the scientific application of the CLASSY data. In particular, we find that accurately accounting for flux calibration offsets can affect the derived properties of the stellar populations, while customized extractions of NUV spectra for extended sources are essential for correctly diagnosing the metallicity of galaxies via C iii] nebular emission. Despite changes in spectral resolution of up to ∼25% between individual data sets (due to changes in the COS line-spread function), no adverse affects were observed on the difference in velocity width and outflow velocities of isolated absorption lines when measured in the final combined data products, owing in part to our signal-to-noise regime of S/N < 20.

Strong nebular emission lines are an important diagnostic tool for tracing the evolution of star-forming galaxies across cosmic time. However, different observational setups can affect these lines, and the derivation of the physical nebular properties. We analyze 12 local star-forming galaxies from the COS Legacy Spectroscopy SurveY (CLASSY) to assess the impact of using different aperture combinations on the determination of the physical conditions and gas-phase metallicity. We compare optical spectra observed with the Sloan Digital Sky Survey Data Release aperture, which has a 3″ diameter similar to COS, IFU, and long-slit spectra, including new LBT/MODS observations of five CLASSY galaxies. We calculate the reddening, electron densities and temperatures, metallicities, star formation rates, and equivalent widths (EWs). We find that measurements of the electron densities and temperatures, and metallicity remained roughly constant with aperture size, indicating that the gas conditions are relatively uniform for this sample. However, using IFU observations of three galaxies, we find that the E(B - V) values derived from the Balmer ratios decrease (by up to 53%) with increasing aperture size. The values change most significantly in the center of the galaxies, and level out near the COS aperture diameter of 2.″5. We examine the relative contributions from the gas and stars using the Hα and [O iii] λ5007 EWs as a function of aperture light fraction, but find little to no variations within a given galaxy. These results imply that the optical spectra provide nebular properties appropriate for the far-UV CLASSY spectra, even when narrow 1.″0 long-slit observations are used.

Far-ultraviolet (FUV; ∼1200-2000 Å) spectra are fundamental to our understanding of star-forming galaxies, providing a unique window on massive stellar populations, chemical evolution, feedback processes, and reionization. The launch of the James Webb Space Telescope will soon usher in a new era, pushing the UV spectroscopic frontier to higher redshifts than ever before; however, its success hinges on a comprehensive understanding of the massive star populations and gas conditions that power the observed UV spectral features. This requires a level of detail that is only possible with a combination of ample wavelength coverage, signal-to-noise, spectral-resolution, and sample diversity that has not yet been achieved by any FUV spectral database. We present the Cosmic Origins Spectrograph Legacy Spectroscopic Survey (CLASSY) treasury and its first high-level science product, the CLASSY atlas. CLASSY builds on the Hubble Space Telescope (HST) archive to construct the first high-quality (S/N1500 Å ≳ 5/resel), high-resolution (R ∼ 15,000) FUV spectral database of 45 nearby (0.002 < z < 0.182) star-forming galaxies. The CLASSY atlas, available to the public via the CLASSY website, is the result of optimally extracting and coadding 170 archival+new spectra from 312 orbits of HST observations. The CLASSY sample covers a broad range of properties including stellar mass (6.2 < log M ⋆(M ⊙) < 10.1), star formation rate (−2.0 < log SFR (M ⊙ yr−1) < +1.6), direct gas-phase metallicity (7.0 < 12+log(O/H) < 8.8), ionization (0.5 < O32 < 38.0), reddening (0.02 < E(B − V) < 0.67), and nebular density (10 < n e (cm−3) < 1120). CLASSY is biased to UV-bright star-forming galaxies, resulting in a sample that is consistent with the z ∼ 0 mass-metallicity relationship, but is offset to higher star formation rates by roughly 2 dex, similar to z ≳ 2 galaxies. This unique set of properties makes the CLASSY atlas the benchmark training set for star-forming galaxies across cosmic time.

The epoch of reionization (6 < z < 10) marks the period in our universe whenthe first large galaxies grew to fruition, and began to affect the universearound them. Massive stars, and potentially accreting supermassive black holes,filled the universe with ionizing radiation, burning off the haze of neutralgas that had filled the intergalactic medium (IGM) since recombination(z~1000). The evolution of this process constrains key properties of theseearliest luminous sources, thus observationally constraining reionization is akey science goal for the next decade. The measurement of Lyman-alpha emissionfrom photometrically-identified galaxies is a highly constraining probe ofreionization, as a neutral IGM will resonantly scatter these photons, reducingdetectability. While significant work has been done with 8-10m telescopes,these observations require extremely large telescopes (ELTs); the flux limitsavailable from today's 10m class telescopes are sufficient for only thebrightest known galaxies (m < 26). Ultra-deep surveys with the Giant MagellanTelescope (GMT) and Thirty Meter Telescope (TMT) will be capable of detectingLyman-alpha emission from galaxies 2-3 magnitudes fainter than today's deepestsurveys. Wide-field fiber spectroscopy on the GMT combined with narrow-fieldAO-assisted slit spectroscopy on the TMT will be able to probe the expectedsize of ionized bubbles throughout the epoch of reionization, following updegree scale deep imaging surveys with the Wide Field Infrared Space Telescope.These data will provide the first resolved Lyman-alpha-based maps of theionized intergalactic medium throughout the epoch of reionization, constrainingmodels of both the temporal and spatial evolution of this phase change.

Purpose: In England, health care policy promotes specialized age-appropriate cancer services for teenagers and young adults (TYA), for those aged 13–24 years at diagnosis. Specialist Principal Treatment Centers (PTCs) provide enhanced age-specific care for TYA, although many still receive all or some of their care in adult or children's cancer services. Our aim was to determine the patient-reported outcomes associated with TYA-PTC based care. Methods: We conducted a multicenter cohort study, recruiting 1114 TYA aged 13–24 years at diagnosis. Data collection involved a bespoke survey at 6,12,18, 24, and 36 months after diagnosis. Confounder adjusted analyses of perceived social support, illness perception, anxiety and depression, and health status, compared patients receiving NO-TYA-PTC care with those receiving ALL-TYA-PTC and SOME-TYA-PTC care. Results: Eight hundred and thirty completed the first survey. There was no difference in perceived social support, anxiety, or depression between the three categories of care. Significantly higher illness perception was observed in the ALL-TYA-PTC and SOME-TYA-PTC group compared to the NO-TYA-PTC group, (adjusted difference in mean (ADM) score on Brief Illness Perception scale 2.28 (95% confidence intervals [CI] 0.48–4.09) and 2.93 [1.27–4.59], respectively, p = 0.002). Similarly, health status was significantly better in the NO-TYA-PTC (ALL-TYA-PTC: ADM −0.011 [95%CI −0.046 to 0.024] and SOME-TYA-PTC: −0.054 [−0.086 to −0.023]; p = 0.006). Conclusion: The reason for the difference in perceived health status is unclear. TYA who accessed a TYA-PTC (all or some care) had higher perceived illness. This may reflect greater education and promotion of self-care by health care professionals in TYA units. [ABSTRACT FROM AUTHOR]

Rest-frame far-ultraviolet spectra are fundamental to our understanding of star-forming galaxies, providing a unique window on massive star populations (MSs), chemical evolution, feedback processes, and reionization. JWST is ushering in a new era, pushing the FUV frontier beyond z=10. The success of such endeavors hinges on a comprehensive understanding of the MSs and gas conditions that power the observed spectra. The COS Legacy Archive Spectroscopic SurveY (CLASSY) is a powerful and promising solution providing high-quality, high-resolution FUV spectra of 45 nearby star-forming galaxies. The spectra contain a suite of features that simultaneously characterize the MSs that populate metal-poor galaxies, physical properties of large-scale outflows, and chemical abundance patterns. The CLASSY sample is consistent with the z 0 mass-metallicity relationship and spans 1.5 dex in metallicity. These unique properties make CLASSY the benchmark training set for studies of MSs in star-forming galaxies both across cosmic time and connecting metal-poor to metal-rich populations. [ABSTRACT FROM AUTHOR]

Simple Summary: Developing cancer during adolescence or young adulthood adds extra challenges to an already difficult period of development. This can cause a 'biographical disruption,' in the sense that people miss out on key milestones they might reasonably have expected to achieve during the period, and this can affect their emotional wellbeing. While research shows that young people may experience various degrees of emotional distress, less is known about the emotional experiences and barriers young people experience when accessing help and support. We interviewed two groups of young people who were within 6 months of diagnosis and 3–5 years after treatment. We found three themes that described emotional health experiences: the emotional impact of cancer; personal barriers to support; and support to improve mental health. Differences were identified across the treatment journey, in which we were able to propose therapies and interventions that could be used to help improve psychological outcomes. The biographical disruption that occurs in adolescents and young adults following a cancer diagnosis can affect various important psychosocial domains including relationships with family and friends, sexual development, vocational and educational trajectories, and physical and emotional wellbeing. While there is evidence of the physical impact of cancer during this period, less is known about the impact on emotional wellbeing and especially on the barriers for young people accessing help and support. We aimed to obtain a more in-depth understanding of young people's experiences of their diagnosis, treatment, psychological impact, and range of resources they could or wanted to access for their mental health. We conducted an in-depth qualitative study using semi-structured interviews with 43 young people who had developed cancer aged 16 to 39 years and were either within 6 months of diagnosis or 3–5 years after treatment had ended. Framework analysis identified three themes: the emotional impact of cancer (expressed through anxiety, anger, and fear of recurrence); personal barriers to support through avoidance; and support to improve mental health through mental health services or adolescent and young adult treatment teams. We showed the barriers young people have to access care, particularly participant avoidance of support. Interrupting this process to better support young people and provide them with flexible, adaptable, consistent, long-term psychological support has the potential to improve their quality of life and wellbeing. [ABSTRACT FROM AUTHOR]

Adolescent and young adults (AYA) with germ cell tumours (GCT) have poorer survival rates than children and many older adults with the same cancers. There are several likely contributing factors to this, including the treatment received. The prognostic benefit of intended dose intensity is well documented in GCT from trials comparing regimens. However, evidence specific to AYA is limited by poor recruitment of AYA to trials and dose delivery outside trials not being well examined. We examined the utility of cancer registration data and a clinical trials dataset to investigate the delivery of relative dose intensity (RDI) in routine National Health Service practice in England, compared to within international clinical trials. Linked data from the Cancer Outcomes and Services Dataset (COSD) and the Systemic Anti‐Cancer Therapy (SACT) dataset, and data from four international clinical trials were analysed. Survival over time was described using Kaplan‐Meier estimation; overall, by age category, International Germ‐Cell Cancer Collaborative Group (IGCCCG) classification, stage, tumour subtype, primary site, ethnicity and deprivation. Cox regression models were used to determine the fully adjusted effect of RDI on mortality risk. The quality of both datasets was critically evaluated and clinically enhanced. RDI was found to be well maintained in all datasets with higher RDIs associated with improved survival outcomes. Real‐world data demonstrated several strengths, including population coverage and inclusion of sociodemographic variables and comorbidity. It is limited in GCT however, by the poor completion of data items enabling risk classification of patients and a higher proportion of missing data. [ABSTRACT FROM AUTHOR]

Data resource basics Cancer is a rare disease in children and young people[8],[9] and is commonly defined such that it includes any malignant tumour or benign central nervous system (CNS) tumour. Innovative data linkages with routinely collected administrative data facilitate the Yorkshire Register's world-leading programme of research on childhood and young-adult cancer outcomes, extending into ground-breaking areas of social and psychosocial morbidity. Key Features The Yorkshire Register is an established population-based research database of tumours diagnosed in the childhood, adolescent and young-adult age ranges.[1] Set up in 1984 to describe medium- and long-term outcomes for cancer survivors, it remains one of only three specialist databases in the UK covering the paediatric age range and the only one of its kind covering individuals diagnosed aged 25-29 years. 5 SMNs are defined as a malignant neoplasm of any site with a different morphology from that of the primary tumour regardless of time since diagnosis according to the recommended coding of multiple primary cancers.[21],[22] 6 ICCC-3, International Classification of Childhood Cancer (third edition)[20]; CNS, central nervous system. [Extracted from the article]

The Hubble Deep Field provides one of the deepest multiwave-length views of the distant Universe and has led to the detection of thousands of galaxies seen throughout cosmic time (1). An early map of the Hubble Deep Field at a wavelength of 850 micrometres, which is sensitive to dust emission powered by star formation, revealed the brightest source in the field, dubbed HDF 850.1 (ref. 2). For more than a decade, and despite significant efforts, no counterpart was found at shorter wavelengths, and it was not possible to determine its redshift, size or mass (3-7). Here we report a redshift of z = 5.183 for HDF 850.1, from a millimetre-wave molecular line scan. This places HDF 850.1 in a galaxy overdensity at z ≅ 5.2, corresponding to a cosmic age of only 1.1 billion years after the Big Bang. This redshift is significantly higher than earlier estimates (3,4,6,8) and higher than those of most of the hundreds of submillimetre-bright galaxies identified so far. The source has a star-formation rate of 850 solar masses per year and is spatially resolved on scales of 5 kiloparsecs, with an implied dynamical mass of about 1.3 X 10 (11) solar masses, a significant fraction of which is present in the form of molecular gas. Despite our accurate determination of redshift and position, a counterpart emitting starlight remains elusive., We have obtained a full-frequency scan of the 3-mm band towards the Hubble Deep Field using the IRAM (Institut de Radioastronomie Millinietrique) Plateau de Bure Interferometer. The observations covered the [...]

Rest-frame far-ultraviolet spectra are fundamental to our understanding of star-forming galaxies, providing a unique window on massive star populations (MSs), chemical evolution, feedback processes, and reionization. JWST is ushering in a new era, pushing the FUV frontier beyond z=10. The success of such endeavors hinges on a comprehensive understanding of the MSs and gas conditions that power the observed spectra. The COS Legacy Archive Spectroscopic SurveY (CLASSY) is a powerful and promising solution providing high-quality, high-resolution FUV spectra of 45 nearby star-forming galaxies. The spectra contain a suite of features that simultaneously characterize the MSs that populate metal-poor galaxies, physical properties of large-scale outflows, and chemical abundance patterns. The CLASSY sample is consistent with the z 0 mass-metallicity relationship and spans 1.5 dex in metallicity. These unique properties make CLASSY the benchmark training set for studies of MSs in star-forming galaxies both across cosmic time and connecting metal-poor to metal-rich populations. [ABSTRACT FROM AUTHOR]

Objective: Adolescents and young adults (AYAs) diagnosed with cancer commonly experience elevated psychological distress and need appropriate detection and management of the psychosocial impact of their illness and treatment. This paper describes the multinational validation of the Distress Thermometer (DT) for AYAs recently diagnosed with cancer and the relationship between distress and patient concerns on the AYA‐Needs Assessment (AYA‐NA). Methods: AYA patients (N = 288; 15–29 years, Mage = 21.5 years, SDage = 3.8) from Australia (n = 111), Canada (n = 67), the UK (n = 85) and the USA (n = 25) completed the DT, AYA‐NA, Hospital Anxiety Depression Scale (HADS) and demographic measures within 3 months of diagnosis. Using the HADS as a criterion, receiver operating characteristics analysis was used to determine the optimal cut‐off score and meet the acceptable level of 0.70 for sensitivity and specificity. Correlations between the DT and HADS scores, prevalence of distress and AYA‐NA scores were reported. Results: The DT correlated strongly with the HADS‐Total, providing construct validity evidence (r = 0.65, p < 0.001). A score of 5 resulted in the best clinical screening cut‐off on the DT (sensitivity = 82%, specificity = 75%, Youden Index = 0.57). Forty‐two percent of AYAs scored at or above 5. 'Loss of meaning or purpose' was the AYA‐NA item most likely to differentiate distressed AYAs. Conclusions: The DT is a valid distress screening instrument for AYAs with cancer. The AYA‐POST (DT and AYA‐NA) provides clinicians with a critical tool to assess the psychosocial well‐being of this group, allowing for the provision of personalised support and care responsive to individuals' specific needs and concerns. [ABSTRACT FROM AUTHOR]