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Studying the interplay between massive star formation and the interstellar medium (ISM) is paramount to understand the evolution of galaxies. Radio continuum (RC) emission serves as an extinction-free tracer of both massive star formation and the energetic components of the interstellar medium. We present a multi-band radio continuum survey of the local group galaxy M 33 down to ~30 pc linear resolution observed with the Karl G. Jansky Very Large Array (VLA). We calibrate the star-formation rate surface density and investigate the impact of diffuse emission on this calibration using a structural decomposition. Separating the thermal and nonthermal emission components, the correlation between different phases of the interstellar medium and the impact of massive star formation are also investigated. Radio sources with sizes, 20 pages, 12 figures, accepted for publication in MNRAS journal

The Advanced Telescope for High Energy Astrophysics (Athena) is the X-ray observatory large mission selected by the European Space Agency (ESA), within its Cosmic Vision 2015-2025 programme, to address the "Hot and Energetic Universe" scientific theme (Nandra et al. 2013), and it is provisionally due for launch in the early 2030s. The Square Kilometer Array (SKA) is the next generation radio observatory and consists of two telescopes, one comprised of dishes operating at mid frequencies (SKA1-MID) and located in South Africa, and the other comprised of Log-Periodic antennas operating at low radio frequencies (SKA1-LOW), which will be located in Australia (Braun et al. 2017). The scientific commissioning of the radio telescope is planned to begin in 2021-2022. The SKA-Athena Synergy Team (SAST) has been tasked to single out the potential scientific synergies between Athena and SKA. The astrophysical community was involved in this exercise primarily through a dedicated SKA-Athena Synergy Workshop, which took place on April 24-25, 2017 at SKAO, Jodrell Bank, Manchester. The final result of the synergy exercise, this White Paper, describes in detail a number of scientific opportunities that will be opened up by the combination of Athena and SKA, these include: 1. the Cosmic Dawn; 2. the Evolution of black holes and galaxies; 3. Active galaxy feedback in galaxy clusters; 4. Non-thermal phenomena in galaxy clusters; 5. Detecting the cosmic web; 6. Black-hole accretion physics and astrophysical transients; 7. Galactic astronomy: stars, planets, pulsars and supernovae., Comment: 79 pages, 28 figures. A high resolution version of the White Paper is available here: https://drive.google.com/open?id=1HpuGUlDGl2oWHV7j7fQPDYnkZZ15af2I

We show that gaseous \HI disks of primordial composition irradiated by an external radiation field can develop a multiphase medium with temperatures between 10^2 and 10^4 K due to the formation of molecular hydrogen. For a given \HI column density there is a critical value of the radiation field below which only the cold \HI phase can exist. Due to a time decreasing quasar background, the gas starts cooling slowly after recombination until the lowest stable temperature in the warm phase is reached at a critical redshift $z=z_{cr}$. Below this redshift the formation of molecular hydrogen promotes a rapid transition towards the cold \HI phase. We find that disks of protogalaxies with $10^{20}\simlt N_{HI}\simlt 10^{21} cm^{-2}$ are gravitationally stable at $T\sim 10^4$ K and can start their star formation history only at $z \simlt z_{cr}\sim 2$, after the gas in the central portion of the disk has cooled to temperatures $T\simlt 300$ K. Such a delayed starbust phase in galaxies of low gas surface density and low dynamical mass can disrupt the disks and cause them to fade away. These objects could contribute significantly to the faint blue galaxy population., Comment: 16 pages (LaTeX), 2 Figures to be published in Astrophysical Journal Letters

The aim of this study was to evaluate the age of immigrants' children at diagnosis of Type 1 diabetes (T1DM) according to their country of birth. Immigration from developing countries to a westernised area causes rapid changes in the environmental conditions, and we investigated whether the location of birth, either inside or outside Italy, is associated with age at diagnosis of diabetes. Out of a prevalent hospital-based cohort of 5718 T1DM children cared for in 2002 in 47 Italian Pediatric Diabetes Units, we recruited 195 children (M: 97) of immigrants from developing countries--119 were born in Italy and 76 outside the European Union. Children with only one immigrant parent (no. 42) were also included. Age at diagnosis of T1DM, and other variables were compared with those of Italian children. Children of immigrated families born in Italy developed T1DM at a median age of 4.0 yr (IQR 2.2-6.9), whereas those born in developing countries and that had immigrated to Italy after birth developed T1DM at a median age of 7.9 yr (IQR 5.1-10.7, p < 0.001). Among the children born in Italy, 77 had parents who were both immigrants and the children's median age at diagnosis was 3.8 yr (IQR 2.1-6.3); 42 had only one immigrant parent and, when it was the father (no. = 23), median age was even younger (2.9 yr, IQR 2.0-8.2). Ten children had immigrated in their first yr of life and their median age was 9.1 yr (IQR 5.0-10.6). The median age of the Italian children was 6.6 yr (IQR 3.6-9.5). Results show that the outbreak of T1DM is earlier in immigrants' children born in Italy than in original countries.

Purpose: To describe the use of silicone oil (SO) in combination with subretinal recombinant tissue plasminogen activator (rtPA) to achieve dislocation of large subretinal hemorrhage secondary to exudative age-related macular degeneration (AMD). Methods: A single-eye 81-year-old woman, known for exudative AMD, presented for a profound vision loss in her left eye since 7 days due to a massive subretinal hemorrhage. She promptly underwent standard three-port pars plana vitrectomy with subretinal injection of rtPA and SO tamponade. Results: The surgical technique showed favorable anatomical and functional outcomes, achieving a substantial peripheral displacement of blood and visual improvement. Conclusion: This report favorably supports the use of SO in adjunction to subretinal rtPA in selected cases of subretinal hemorrhage secondary to wet AMD.

Purposes: To describe the prevalence of ocular features among COVID-19 patients and their relationship with clinical data, inflammatory markers and respiratory support therapy (including CPAP); to investigate SARS-CoV-2 in ocular secretions of symptomatic patients. Methods: 172 COVID-19 patients were evaluated for presence of ocular manifestations. Clinical and laboratory data were also reviewed. Conjunctival swabs were analyzed for SARS-CoV-2 by RT-PCR. Results: Forty-five patients (26.2%) reported ocular manifestations. Patients treated with CPAP were more likely to have ocular abnormalities (p

Purpose: To investigate the optical coherence tomography (OCT) en face reconstruction of the choroid in different phenotypes of non-neovascular age-related macular degeneration (AMD), to identify the relative distribution of the vascular patterns of the Haller’s layer in each AMD category. Methods: Retrospective study enrolling consecutive patients with non-neovascular AMD. Patients were divided into the following: (1) those with reticular pseudodrusen (RPD); (2) those with small (< 63μm) or medium–large drusen (63–124μm); (3) those with geographic atrophy (GA). Qualitative analysis of the en face images provided by CIRRUS HD-OCT 5000 (Carl Zeiss Meditech, Inc., Dublin, USA) was performed, identifying five arrangements of Haller’s vessels: temporal herringbone, branched from below, laterally diagonal, double arcuate, and reticular. Choroidal thickness (CT) was measured from structural OCT. Healthy age-matched subjects were included as a control group. Results: Fifty-eight eyes of 58 patients (20 eyes with RPD; 22 eyes with drusen; 16 eyes with GA) and 18 control eyes were enrolled. The laterally diagonal configuration was the most prevalent (40.0%) in the RPD group; the reticular pattern was the most frequent in the drusen group (50.0%); the double arcuate (62.5%) was the most recurrent pattern in patients with GA. In the control group, the temporal herringbone (38.9%) arrangement was the most represented. The CT associated with the temporal herringbone and reticular arrangement was significantly higher compared to the branched from below (p < 0.001), the laterally diagonal (p = 0.014), and the double arcuate pattern (p = 0.009). Conclusion: Different phenotypes of non-neovascular AMD present a specific distribution of vascular arrangement on en face OCT. The temporal herringbone and the reticular pattern (the ones more associated in a physiological setting) disclosed a thicker choroid compared to the arrangements more represented in non-neovascular AMD-correlated phenotypes.

PurposeTo describe optical coherence tomography (OCT) features in the Bruch's membrane (BM) of eyes with angioid streaks (AS) and evaluate their evolution over the follow-up.Patients and methodsPatients with AS presenting between March 2016 and September 2016 at two tertiary referral centers were consecutively recruited in this study. Eligibility criteria included prior spectral domain (SD)-OCT images, taken at least 3 months before at the same referral center, with automated eye tracking and image alignment modules. Alterations of BM were described and compared to previous scans over the follow-up. Multimodal imaging was used to identify alteration of retinal pigment epithelium (RPE) and choroid.ResultsThirty-two eyes of 16 consecutive patients with AS were included. BM undulations, mostly observed around the optic nerve head, were found in 19 (59.4%) of 32 eyes. BM breaks were found in 31 (96.9%) out of 32 eyes. Evolution of BM undulations into BM breaks was observed in 5 eyes (15.6%). Choroidal neovascularization (CNV) was observed in 12 eyes (37.5%) during follow-up, typically in areas of BM interruption.ConclusionsBM undulations, probably caused by high stretching forces exerted on the BM around the optic nerve head, seem to precede some BM breaks. BM interruptions may be a preferred way for the growth of CNV, which was identified in one-third of our cases.

Purpose: To provide an integrate multimodal imaging characterization of peripheral drusen in the eyes with and without macular signs of age-related macular degeneration (AMD) and to analyze their association with macular findings. Methods: In this retrospective, cross-sectional study, subjects with peripheral drusen were imaged with the Optos (Optos PLC, Dunfermline, Scotland, UK) and Spectralis devices to obtain referenced spectral domain optical coherence tomography (SD-OCT) images. Two experienced graders independently graded the ultra-widefield (UWF) pseudocolor and fundus autofluorescence (FAF) images for the presence of peripheral drusen and analyzed peripheral druse features using OCT. Main outcome measures included quantitative and qualitative assessment of peripheral drusen. Results: Fifty-seven eyes (30 subjects) were included in the analysis. Mean ± SD age was 77.6 ± 9.2years (range 54–97years). On pseudocolor images, graders identified the presence of drusen in all the enrolled eyes (Cohen’s kappa was 1.0). On FAF images, Cohen’s kappa was 0.71. In the topographical assessment, peripheral drusen were detected in 23 cases in the temporal region, in 40 cases in the nasal region, in 40 cases in the inferior region, and in 42 cases in the superior region. On SD-OCT images, peripheral drusen had a high reflective core in 97.1% of cases, while remaining drusen were characterized by a low reflective core. The macula was affected by early/intermediate AMD in 23 eyes (43.5%) and late AMD in 6 eyes (10.5%). Conclusions: We provided an integrate multimodal imaging assessment of peripheral drusen in the eyes with and without AMD. Peripheral drusen were characterized by distinguished features that may suggest that these lesions constitute a distinct disease, rather than representing an expansion of AMD.

Purpose To analyze the frequency and phenotypic variation of AMD in subjects with high myopia (HM), and to describe the clinical course and response to treatment of neovascularization (NV). Methods Patients with HM were identified at five retina tertiary referral centers. Inclusion criteria were myopic patients aged 55 years or more with axial lengths equal or greater than 25.5 mm. Results A total of 874 eyes from 442 HM subjects older than 55 years were identified and 104 eyes of 54 patients (72 ± 11 years) were included in the study and followed up for 23.5 ± 19.5 months. The estimated AMD frequency in HM subjects over 55 years was 11.9% (95% confidence interval; 9.8%-14.0%). A total of 34 of 104 eyes were diagnosed with drusen, 22 with reticular pseudodrusen (RPD), 28 with both drusen and RPD, and 20 with geographic atrophy. Neovascularization was detected in 52 eyes (50%), and type 1 was the most frequent form (39 eyes, 75%). Overall, NV was treated with 4.6 ± 2.6 anti-VEGF injections. Eyes with treatment-naive NV at baseline (n = 34) required 3.8 ± 1.5 anti-VEGF injections during the first year of treatment. This exceeded the injection number in the purely myopic population (1.8 to 3.6 injections for the first year). Conclusions This study provides evidence to suggest that older patients with HM are at a significant risk of the dry and neovascular forms of AMD. NV in eyes with HM and AMD required more injections in the first year compared to NV in HM eyes without AMD.

PURPOSE: To analyze the quantitative and qualitative early changes of choroidal neovascularization (CNV) associated with chronic central serous chorioretinopathy (CSC) after treatment using optical coherence tomography-angiography (OCT-A). METHODS: Charts of consecutive patients with diagnosis of chronic CSC complicated by CNV were retrospectively reviewed. Included patients were divided in photodynamic therapy (PDT) or aflibercept group on the basis of the treatment received (half-fluence PDT or aflibercept 2.0 mg/0.05 ml intravitreal injection). Main outcome measures included the changes between baseline and 1-month follow-up in CNV vessel density (VD) and area on OCT-A images after thresholding and binarization. RESULTS: A total of 30 eyes of 26 Caucasian patients were included: 17 eyes of 15 patients in PDT group (mean age 53 ± 11 years) and 13 eyes of 11 patients in aflibercept group (mean age 58 ± 8 years [p = 0.196]). In both PDT and aflibercept groups, best-corrected visual acuity improved at 1 month, and central macular thickness and subretinal fluid significantly decreased. VD did not change after the treatment in both groups (p = 0.502 and p = 0.086) although CNV area decreased significantly (from 0.586 ± 0.449 mm(2) to 0.553 ± 0.453 mm(2) [0.041]) in the PDT group, and nonsignificantly (from 0.767 ± 0.466 mm(2) to 0.733 ± 0.472 mm(2) [p = 0.095]) in the aflibercept group. The same results were confirmed in the subanalysis of the 18 treatment-naïve eyes. CONCLUSIONS: We demonstrated that, despite all patients showed a favorable clinical response, VD of CNVs complicating chronic CSC did not change after treatment. These findings support the idea that arteriogenesis is the main driving force of CNV in pachychoroid-related macular disorders.

AimTo analyse quantitative optical coherence tomography angiography (OCTA) parameters of choriocapillaris (CC) at the foveal, perifoveal and parafoveal regions in healthy subjects of different age.MethodsIn this observational cross-sectional study, consecutive healthy subjects underwent swept source OCTA (PLEX Elite 9000, Carl Zeiss Meditec, USA). 3×3 mm and 6×6 mm scans centred on the fovea were acquired analysed and postprocessed with thresholding and binarisation processes. The main outcome measures included CC quantitative OCTA features (perfusion density (PD), vessel length density (VLD) and vessel diameter index (VDI)) at the foveal, perifoveal and parafoveal regions, and their relationship with age.ResultsSeventy-two eyes (72 patients, mean age 47.4±19.2 years, mean axial length 24.0±0.7 mm) were included. The mean PD was statistically lower in the foveal region compared with the parafoveal region in 3×3 mm scans (p=0.009). In subjects aged 70–80, PD of the foveal region was significantly reduced compared with the perifoveal region in 6×6 mm scans (p=0.008). A strong negative correlation was found between PD and ageing in the foveal, parafoveal and perifoveal regions (pConclusionsWe reported in vivo a strong negative correlation between PD and ageing in the CC of healthy subjects. This reduction seems related to a reduced diameter, and not to a reduced number, of capillaries. The age-related changes were higher in the central area compared with the perifoveal area.

Best vitelliform macular dystrophy (VMD) is an autosomal dominant inherited dystrophy, most frequently caused by mutations in the BEST1 gene. The authors describe “choroidal caverns,” a previously unreported optical coherence tomography finding in the choriocapillary and choroid of Best VMD. Histopathologic examination in eyes with Best VDM shows extensive deposition of lipofuscin in the retinal pigment epithelium (RPE) throughout the retina and accumulation of fibrillar material under the RPE and in the choroid. This supports the hypothesis that choroidal caverns could be a sign of the degenerative process involving the choroid in eyes with Best VMD. [ Ophthalmic Surg Lasers Imaging Retina . 2018;49:284–287.]

Aims: To analyze retinal vascular plexuses and choriocapillaris by optical coherence tomography angiography (OCT-A) and retinal nerve fiber layer and ganglion cell layer (GCL) by structural optical coherence tomography (OCT) in patients with type 1 diabetes mellitus (T1DM) without diabetic retinopathy (DR). Methods: A total of 25 eyes of 25 consecutive T1DM patients without signs of DR were prospectively recruited and compared to 25 healthy subjects (control eyes). All patients underwent OCT-A (CIRRUS HD-OCT model 5000, Carl Zeiss Meditec, Dublin, CA) and structural OCT. Qualitative and quantitative analyses with vessel density were performed on OCT-A images in the superficial capillary plexus (SCP), deep capillary plexus (DCP) and choriocapillaris for all patients. Results: By means of OCT-A, a rarefaction of the perifoveal capillary network in SCP was detected in 7 out of 25 eyes. No significant difference was found in FAZ area of both SCP and DCP comparing diabetic and control groups. By analyzing the DCP, diabetic eyes revealed a significant decreased vessel density compared to control eyes [0.464±0.016 and 0.477±0.014, respectively (p=0.005)]. Instead, no significant difference was found in the vessel density of all-retina plexus, SCP and choriocapillaris. By RFNL and GCL thickness analysis, no significant differences were disclosed between diabetics and healthy subjects. Conclusions: We demonstrated the ability of OCT-A to disclose early vascular alterations in patients with T1DM diagnosed as without any signs of DR on the basis of fundus biomicroscopy. Our results also suggest that microvascular changes could precede detectable damage of diabetic neuroretinopathy.

Purpose To investigate the application of noninvasive ultra-widefield (UWF) imaging in patients with angioid streaks secondary to pseudoxanthoma elasticum (PXE) and to compare detected findings with those obtainable with 7 standard 30° fields (7SF) imaging. Design Cross-sectional, observational study. Participants Forty eyes of 20 consecutive patients with angioid streaks secondary to PXE (8 women and 12 men; mean age, 56.9 ± 12.3 years). Methods Consecutive patients with angioid streaks secondary to PXE seeking treatment between January and June 2016 at the Medical Retina & Imaging Unit of the Department of Ophthalmology, University Vita-Salute San Raffaele, underwent UWF imaging (California; Optos PLC, Dunfermline, UK). Ultra-widefield color images and fundus autofluorescence (FAF) were evaluated. Ultra-widefield findings then were compared with those obtainable with 7SF. Main Outcome Measures Types and location of retinal lesions secondary to PXE. Results Peripheral lesions not entirely visible with 7SF were identified in 29 of 40 eyes (72.5%; P < 0.0001). These peripheral lesions included peau d'orange (52.5% of the eyes), coquille d'oeuf (52.5%), cracked eggshell (5.0%), comet lesions (27.5%), peripheral retinal degenerations (17.5%), parastreak atrophies (10.0%), and peripheral hemorrhage (5.0%). Furthermore, chorioretinal atrophies, drusen of the optic disc, cracked eggshell, pattern-like dystrophies, and retinal hemorrhages associated with angioid streaks were observed on digital color or FAF images, or both, and described. Conclusions Ultra-widefield imaging showed valuable usefulness in patients with angioid streaks by providing in a single image the entire spectrum of retinal alterations associated with PXE. Peripheral lesions often are present in patients with angioid streaks and may be missed with 7SF imaging. A careful examination of fundus periphery should be performed during screening and follow-up visits.

Age-related macular degeneration (AMD), the most important cause of vision loss in elderly people, is a degenerative disorder of the central retina with a multifactorial etiopathology. AMD is classified in dry AMD (d-AMD) or neovascular AMD depending on the presence of choroidal neovascularization. Currently, no therapy is approved for geographic atrophy, the late form of d-AMD, because no treatment can restore the damage of retinal pigment epithelium (RPE) or photoreceptors. For this reason, all treatment approaches in d-AMD are only likely to prevent and slow down the progression of existing atrophy. This review focuses on the management of d-AMD and especially on current data about potential targets for therapies evaluated in clinical trials. Numerous examinations are available in clinics to monitor morphological changes in the retina, RPE and choroid of d-AMD patients. Fundus autofluorescence and optical coherence tomography (OCT) are considered the most useful tools in the diagnosis and follow-up of d-AMD alterations, including the monitoring of atrophy area progression. Instead, OCT-angiography is a novel imaging tool that may add further information in patients affected by d-AMD. Several pathways, including oxidative stress, deposits of lipofuscin, chronic inflammation and choroidal blood flow insufficiency, seem to play an important role in the pathogenesis of d-AMD and represent possible targets for new therapies. A great number of treatments for d-AMD are under investigation with promising results in preliminary studies. However, only few of these drugs will enter the market, offering a therapeutic chance to patients affected by the dry form of AMD and help them to preserve a good visual acuity. Further studies with a long-term follow-up would be important to test the real safety and efficacy of drugs under investigation.

We describe the Herschel Virgo Cluster Survey (HeViCS) and the first data obtained as part of the Science Demonstration Phase (SDP). The data cover a central 4x4 sq deg region of the cluster. We use SPIRE and PACS photometry data to produce 100, 160, 250, 350 and 500 micron luminosity functions (LFs) for optically bright galaxies that are selected at 500 micron and detected in all bands. We compare these LFs with those previously derived using IRAS, BLAST and Herschel-ATLAS data. The Virgo Cluster LFs do not have the large numbers of faint galaxies or examples of very luminous galaxies seen previously in surveys covering less dense environments., Letter accepted for publication in A&A (Herschel special issue)