Most of the photons that reionized the Universe came from dwarf galaxies.

The identification of sources driving cosmic reionization, a major phase transition from neutral hydrogen to ionized plasma around 600-800 Myr after the Big Bang1-3, has been a matter of debate4. Some models suggest that high ionizing emissivity and escape fractions (fesc) from quasars support their role in driving cosmic reionization5,6. Others propose that the high fesc values from bright galaxies generate sufficient ionizing radiation to drive this process7. Finally, a few studies suggest that the number density of faint galaxies, when combined with a stellar-mass-dependent model of ionizing efficiency and fesc, can effectively dominate cosmic reionization8,9. However, so far, comprehensive spectroscopic studies of low-mass galaxies have not been done because of their extreme faintness. Here we report an analysis of eight ultra-faint galaxies (in a very small field) during the epoch of reionization with absolute magnitudes between MUV ≈ -17 mag and -15 mag (down to 0.005L⋆ (refs. 10,11)). We find that faint galaxies during the first thousand million years of the Universe produce ionizing photons with log[ξion (Hz erg-1)] = 25.80 ± 0.14, a factor of 4 higher than commonly assumed values12. If this field is representative of the large-scale distribution of faint galaxies, the rate of ionizing photons exceeds that needed for reionization, even for escape fractions of the order of 5%.

A high black-hole-to-host mass ratio in a lensed AGN in the early Universe.

Early JWST observations have uncovered a population of red sources that might represent a previously overlooked phase of supermassive black hole growth1-3. One of the most intriguing examples is an extremely red, point-like object that was found to be triply imaged by the strong lensing cluster Abell 2744 (ref. 4). Here we present deep JWST/NIRSpec observations of this object, Abell2744-QSO1. The spectroscopy confirms that the three images are of the same object, and that it is a highly reddened (AV ≃ 3) broad emission line active galactic nucleus at a redshift of zspec = 7.0451 ± 0.0005. From the width of Hß (full width at half-maximum = 2,800 ± 250 km s-1), we derive a black hole mass of M BH = 4 - 1 + 2 × 1 0 7 M ⊙ . We infer a very high ratio of black-hole-to-galaxy mass of at least 3%, an order of magnitude more than that seen in local galaxies5 and possibly as high as 100%. The lack of strong metal lines in the spectrum together with the high bolometric luminosity (Lbol = (1.1 ± 0.3) × 1045 erg s-1) indicate that we are seeing the black hole in a phase of rapid growth, accreting at 30% of the Eddington limit. The rapid growth and high black-hole-to-galaxy mass ratio of Abell2744-QSO1 suggest that it may represent the missing link between black hole seeds6 and one of the first luminous quasars7.

Age-associated alterations of brain mitochondria energetics.

The study aimed to explore the role of age-associated elevated cytosolic Ca2+ in changes of brain mitochondria energetic processes. Two groups of rats, young adults (4 months) and advanced old (24 months), were evaluated for potential alterations of mitochondrial parameters, the oxidative phosphorylation (OxPhos), membrane potential, calcium retention capacity, activity of glutamate/aspartate carrier (aralar), and ROS formation. We demonstrated that the brain mitochondria of older animals have a lower resistance to Ca2+ stress with resulting consequences. The suppressed complex I OxPhos and decreased membrane potential were accompanied by reduction of the Ca2+ threshold required for induction of mPTP. The Ca2+ binding sites of mitochondrial aralar mediated a lower activity of old brain mitochondria. The altered interaction between aralar and mPTP may underlie mitochondrial dysregulation leading to energetic depression during aging. At the advanced stages of aging, the declined metabolism is accompanied by the diminished oxidative background.

Magnetic resonance imaging validation of medial transthyroid ultrasound-guided stellate ganglion block: A pilot study.

OBJECTIVE: Ultrasound-guided stellate ganglion block (usSGB) facilitates improved accuracy of needle position and application of lesser volumes of local anesthetic (LA). Approaches of usSGB, however, have not fully been optimized with respect to efficacy and technical convenience. This pilot study examined the anatomical position and spatial distribution of a small volume of LA injectate dispensed by medial transthyroid usSGB via magnetic resonance imaging (MRI) and assessment of its effect on cervical sympathetic nerves. METHODS: Twelve healthy males were tested in a double-blinded within-subject design. In a total of 37 usSGB, 3 ml of LA and saline 0.9% solution were injected intramuscularly into the longus colli muscle (LCM) preventing uncontrollable spread of LA within cervical structures. Immediately after injection, distribution of injectate was traced by MRI. Twenty-four out of the 37 usSGB-injections with 3 ml ropivacaine 1% (verum) and saline 0.9% (placebo) were compared. Efficacy of usSGB was assessed by the appearance of oculosympathetic paresis and increases in skin temperature. RESULTS: All usSGBs were positioned in the proximity of the LCM muscle belly. Most of the axial injectate was distributed within the transversal plane between the middle section of C5 and the upper section of T1 vertebra. Signs of oculosympathetic paresis and skin temperature increase were found exclusively under verum conditions. CONCLUSION: This pilot study demonstrated the feasibility of medial transthyroid usSGB using an out-of-plane technique and a volume of 3 ml of LA. Further studies are required to establish the relative value and safety of this technique compared to other published approaches.

Ethical Pain and Terminal Chaperonage.

Terminal chaperonage embedded in palliative care deeply resonates with human needs and has undergone significant advances in the past decades. At the same time, it is in jeopardy due to austerity measures in healthcare. Its comprehensive translation in philanthropic end-of-life practice necessitates reflection on underlying ethical issues. This chapter addresses ethical aspects arising in pain and terminal chaperonage and deduces important ethical imperatives in the wake of the palliative mandate. The imperatives affect the deployment of resources necessary for a humane pain and terminal chaperonage, one that is to be comprehensive and flexible in design and implementation at the same time. Furthermore, they are concerned with critical implications for dying clients emerging from the idiosyncratic properties of opioids with respect to their potential to induce mental status alterations. Given that living and dying are profoundly mental by nature, the human mind plays a fundamental role in the command of both. Based on this, this chapter also outlines the essentials of terminal thought plasticity and affect catharsis en route to a mindful, decent death. It identifies and advocates eight most fundamental affective, respectively cognitive fields of the human mind, the "Ensemble of the essential eight iridescent fields of relinquishment", whose adaptable, culturally sensitive facilitation in mental management prior to death may have to be considered the core ethical imperative in terminal chaperonage - in true congruence with philanthropic end-of-life care.

The formation of submillimetre-bright galaxies from gas infall over a billion years.

Submillimetre-bright galaxies at high redshift are the most luminous, heavily star-forming galaxies in the Universe and are characterized by prodigious emission in the far-infrared, with a flux of at least five millijanskys at a wavelength of 850 micrometres. They reside in haloes with masses about 10(13) times that of the Sun, have low gas fractions compared to main-sequence disks at a comparable redshift, trace complex environments and are not easily observable at optical wavelengths. Their physical origin remains unclear. Simulations have been able to form galaxies with the requisite luminosities, but have otherwise been unable to simultaneously match the stellar masses, star formation rates, gas fractions and environments. Here we report a cosmological hydrodynamic galaxy formation simulation that is able to form a submillimetre galaxy that simultaneously satisfies the broad range of observed physical constraints. We find that groups of galaxies residing in massive dark matter haloes have increasing rates of star formation that peak at collective rates of about 500-1,000 solar masses per year at redshifts of two to three, by which time the interstellar medium is sufficiently enriched with metals that the region may be observed as a submillimetre-selected system. The intense star formation rates are fuelled in part by the infall of a reservoir gas supply enabled by stellar feedback at earlier times, not through major mergers. With a lifetime of nearly a billion years, our simulations show that the submillimetre-bright phase of high-redshift galaxies is prolonged and associated with significant mass buildup in early-Universe proto-clusters, and that many submillimetre-bright galaxies are composed of numerous unresolved components (for which there is some observational evidence).

Effectiveness, Safety, and Predictive Potential in Ultrasound-Guided Stellate Ganglion Blockades for the Treatment of Sympathetically Maintained Pain.

BACKGROUND: Evaluating the effectiveness of stellate ganglion blockades (SGBs) proves challenging, since the criteria defining a successful blockade are controversial. This may be one reason for the scarcity of studies on this topic, thus forcing clinical guidelines to remain conservative in recommending SGBs. Moreover, factors to predict which patients will benefit from blockade series are not yet available. OBJECTIVES: The objectives of this study were to evaluate through a clinical approach SGBs' effectiveness performed under ultrasound guidance (us-SGB) and to identify factors to predict effectiveness. METHODS: We retrospectively analyzed 809 us-SGBs in 105 patients with complex regional pain syndrome (CRPS) and neuropathic pain syndromes (all potentially including sympathetically maintained pain) regarding pain reduction. Volume and type of local anesthetics, magnitude of pain, temperature of the dorsal hands, heart rate, blood pressure, and occurrence of Horner's syndrome or complications were assessed. RESULTS: Pain reduction after a blockade series was highly significant and showed no significant correlation with change of temperature, vital signs, or Horner's syndrome. For patients with neuropathic pain, the predictive potential for pain reduction following a blockade series lies within the range of pain reduction after the first blockade. In a literature comparison, incidences of complications (hoarseness 3.9%, dysphagia 3.4%, hematoma 0.6%) were lower than in non-ultrasound-guided techniques. CONCLUSIONS: Data indicate that us-SGBs are safe and effective in reducing sympathetically maintained pain in patients with CRPS and neuropathic pain syndromes. Pain reduction after the first blockade may predict total pain reduction after a blockade series. Other clinical measures seem unsuitable to predict effectiveness.

Body-Related Emotions in Posttraumatic Stress Disorder Following Childhood Sexual Abuse.

Traumatic experiences are associated with emotions such as anxiety, shame, guilt, disgust, and anger. For patients who have experienced child sexual abuse, these emotions might be triggered by perceptions of their own body. The aim of this study was to investigate the extent of the association of the body to traumatic experiences and to discern the emotions linked to trauma-associated body areas. Ninety-seven female participants were assigned to four groups: post-traumatic stress disorder following child sexual abuse with co-occurring borderline personality disorder, post-traumatic stress disorder following child sexual abuse without co-occurring borderline personality disorder, borderline personality disorder without post-traumatic stress disorder, and healthy controls. Participants rated 26 body areas regarding their association with trauma and 7 emotions. Emotions were assessed by questionnaires. Results suggest that specific areas of the body are associated with trauma and linked to highly aversive emotions. In post-traumatic stress disorder patients, the areas associated with highly negative emotions were the pubic region and inner thighs. Thus, the patient's body may act as a trigger for traumatic memories.

Ultrasound-guided stellate ganglion blocks combined with pharmacological and occupational therapy in Complex Regional Pain Syndrome (CRPS): a pilot case series ad interim.

OBJECTIVE: This preliminary and retrospective pilot case series examines a treatment concept consisting of ultrasound-guided stellate ganglion blocks (SGBs) combined with pharmacological and occupational therapy in patients with complex regional pain syndrome (CRPS) of the hand. Efficacy of combined treatment concepts and safety of ultrasound-guided SGB have not been sufficiently investigated yet. METHODS: A total number of 156 blocks were evaluated in 16 patients with CRPS in a retrospective analysis. All patients received pharmacotherapy and a standard regimen of occupational therapy offered simultaneously to the SGBs. Changes in both spontaneous and evoked pain levels were assessed by numerical pain rating score before and after the last blockade of a series. Side effects were documented. RESULTS: The overall mean pain reduction was 63.2% regarding spontaneous and 45.3% regarding evoked pain. Mild complications, such as hoarseness or dysphagia, occurred in 13.5% of the blocks (21 SGBs). Serious complications, such as plexus paresis or accidental puncture of vessels or other structures, did not occur. Time between symptom onset and start of treatment did not affect the extent of pain reduction. CONCLUSIONS: The combination of ultrasound-guided SGB and simultaneous pharmacological and occupational therapy showed encouraging treatment results under conditions of this pilot case series. Assessment of efficacy of this combined treatment concept and safety of ultrasound-guided SGB require further prospective clinical studies with larger number of participants.

Comprehensive curriculum for phantom-based training of ultrasound-guided intercostal nerve and stellate ganglion blocks.

OBJECTIVE: Ultrasound (US)-guided pain procedures become increasingly important due to their numerous advantages. Solid proficiency is necessary, however, to minimize complications and guarantee adequate performance. To enable beginners to learn the relevant skills in the technique of US-guided stellate ganglion (SGB) and intercostal nerve block (ICB), a training curriculum was developed and tested using self-made phantoms. DESIGN: The curriculum comprised an introduction to the didactics of US, SGB, and ICB, a demonstration of the techniques by an expert user, as well as hands-on training of needle guidance using a gel pad and two phantoms. SUBJECTS: Three groups of participants with different levels of expertise with US-guided procedures took part in the curriculum: 12 medical students with no prior experience, 12 anesthesiologists with some experience, and five senior anesthesiologists who already applied these techniques on a regular basis. METHODS: Participants evaluated the curriculum via questionnaire, and their performance of time until adequate puncture, attempts required for adequate puncture, number of corrections, and unintentional punctures was assessed. RESULTS: The medical students significantly increased their speed during both nerve blocks and reduced the number of attempts and corrections necessary to perform adequate ICB. The anesthesiologists with some experience also increased their speed in both blocks. The participants rated the curriculum as good to very good. CONCLUSIONS: The combination of theoretical teaching, expert demonstration, and hands-on training on phantoms proved useful in acquiring skills needed for US-guided procedures such as SGB and ICB, and can potentially improve graduate and post-graduate medical education.

Body image in patients with posttraumatic stress disorder after childhood sexual abuse and co-occurring eating disorder.

BACKGROUND: Body image is a multidimensional construct with cognitive-affective, behavioral and perceptive components. Survivors of childhood sexual abuse report a disturbance of the cognitive-affective component of their body image but not of the perceptive component. It has not yet been examined whether and how the behavioral component is affected. Also, it is still unknown whether the disturbances might be due to the influence of co-occurring eating disorders. SAMPLING AND METHODS: The cognitive-affective and behavioral components of the body image of 84 female participants with posttraumatic stress disorder (PTSD) after childhood sexual abuse (31 with a co-occurring eating disorder) and 53 healthy participants were assessed via the Dresden Body Image Inventory (Dresdner Körperbildfragebogen-35, DKB-35) and the Body Image Avoidance Questionnaire (BIAQ). RESULTS: PTSD patients reported significantly higher negative scores on all DKB-35 subscales (p < 0.001) and the BIAQ (p = 0.002; p < 0.001). Results remained consistent after accounting for the influence of co-occurring eating disorders (p = 0.021; p = 0.001; p < 0.001). CONCLUSIONS: Results show for the first time that the behavioral component of the body image is impaired in female patients with PTSD in addition to the cognitive-affective component. This is not solely due to a comorbid eating disorder. The effect of established treatments on the body image of PTSD patients should be evaluated and new treatment modules should be developed and tested, if necessary.