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The ALPHA Collaboration, based at the CERN Antiproton Decelerator, has recently implemented a novel beamline for low energy (≲100 eV) positron and antiproton transport between cylindrical Penning traps that have strong axial magnetic fields. Here, we describe how a combination of semianalytical and numerical calculations was used to optimize the layout and design of this beamline. Using experimental measurements taken during the initial commissioning of the instrument, we evaluate its performance and validate the models used for its development. By combining data from a range of sources, we show that the beamline has a high transfer efficiency and estimate that the percentage of particles captured in the experiments from each bunch is (78±3)% for up to 105 antiprotons and (71±5)% for bunches of up to 107 positrons.

ABSTRACT: Background: ''Food deserts'' are areas with limited access to affordable and healthy foods, disproportionately affecting low-income and ethnic-minority communities in the United States. Analogous disparities exist in other disciplines. Our interprofessional team observed ''therapy deserts” in orthopaedic and rehabilitation settings, wherein pediatric patients (particularly those with Medicaid-type insurance) appeared to lack equal access to physical therapy (PT), occupational therapy (OT), and speech-language pathology (SLP) services. Inadequate access to therapy services places patients at risk for worse outcomes. Methods: We conducted a quality improvement project to assess pediatric patients’ access to therapy care in our region. We surveyed all local PT, OT, and SLP clinics identified from a comprehensive listserv maintained by pediatric therapy teams in our institution. Using a scripted questionnaire, we contacted 113 PT, 38 OT, and 82 SLP clinics external to our institution, collecting data on accepted conditions, appointment waitlist periods, and accepted insurance types. Our primary objective was to determine the percentage of clinics that accepted patients with Medicaid-type insurance. We supplemented our survey with an examination of the Area Deprivation Index for each clinic location. Results: 59 PT clinics (52%), 15 OT clinics (39%), and 36 SLP clinics (44%) completed the survey. Clinics often had limited capacity to care for medically complex conditions. Waitlist times varied, with a median wait of 1 week for PT services, 1 month for OT services, and immediate availability for SLP services. Only 14% of responding PT clinics, 53% of OT clinics, and 22% of SLP clinics accepted patients with Medicaid-type insurance. Insufficient reimbursement rates were frequently cited as the reason for not accepting Medicaid-type insurance. Waitlist times were longer for PT and SLP clinics that accepted Medicaid-type insurance compared to those that did not. Moreover, clinics that accepted Medicaid-type insurance were, on average, in more disadvantaged locations. Conclusions: Our findings suggest the existence of “therapy deserts,” where limited access to therapy services is influenced by insurance type and patient complexity. These restrictions likely exacerbate existing health disparities and illustrate a systemic problem rooted in complex social drivers of health. Addressing ''therapy deserts'' requires collaborative efforts from multidisciplinary teams. Key Concepts: (1) ''Food deserts'' are areas with limited access to affordable and healthy foods that disproportionately affect low-income and ethnic-minority communities in the United States. (2) We propose that such “deserts” exist in other disciplines, including orthopaedics, wherein our interprofessional team of health care providers universally observed unequal access to therapy services—including physical therapy (PT), occupational therapy (OT), and speech-language pathology (SLP)—among pediatric patients. (3) Within our geographical region, we found only 1 in 10 PT clinics, 1 in 4 SLP clinics, and 1 in 2 OT clinics accepted pediatric patients with Medicaid-type insurance. Clinics that accepted Medicaid-type insurance were, on average, in more disadvantaged locations than those that did not. (4) The existence of “therapy deserts” likely further exacerbates existing health disparities, and requires immediate attention from orthopaedic surgeons, allied health care providers, policymakers, researchers, and the public. (5) Successfully addressing “therapy deserts” requires a multifaceted approach and may include: expanding insurance coverage for therapy services; offering financial incentives (eg, tax incentives/exemptions) to clinics providing these services; developing partnerships between non-profit and for-profit organizations; implementing innovative methods of delivering therapy services (eg, virtual appointments); upskilling local providers; and involving communities in the development of interventions. Level of Evidence: Level III

Objective: To describe the design, development, and deployment of an electronic health record (EHR)-based application to manage the Mayo Clinic home dialysis program, improve staff efficiency, and ensure delivery of high-quality clinical care. Patients and Methods: At Mayo Clinic, the Cohort Knowledge Intelligence Solutions (CKIS) team develops innovative patient cohort management solutions using the Epic Healthy Planet module. The CKIS team uses a collaborative and agile approach that incorporates feedback from clinical stakeholders and informatics to create these solutions that improve and automate processes for clinical staff, all managed within the EHR. Over several months (September 1, 2019, to December 30, 2020), the clinical nephrology and CKIS teams met regularly to develop in an iterative fashion 2 home dialysis applications. Time spent on various EHR-related home dialysis tasks was compared before and after the implementation of the applications based on the Nursing Efficiency Assessment Tool (NEAT). Results: Two EHR applications were developed for managing home dialysis referrals and enrollments or monitoring, respectively. The applications consolidate all needed information and provide real-time data to manage patients at the individual or population level. Time saved for the 2 dialysis nurses who worked before and after the implementation was 25 and 20.4 minutes per 8-hour shift, respectively. Conclusion: We developed and implemented 2 EHR applications that proved useful and increased efficiency in managing a home dialysis program. These digital tools can facilitate quality metrics reporting, scale the home dialysis program, and improve care delivery.

Laney J Cuddihee,1 Peter Giannulis,1 Sarah Merriner,1 Paul E Runge,2 Victoria Pringels,3 Virginia McGill,3 Mary-Alice Johnson,3 Lindsey B Cobb,4 Robert W Arnold1 1Alaska Blind Child Discovery, Alaska Children’s EYE & Strabismus, Anchorage, AK, USA; 2International Retinal Consultant, Lakewood Ranch, FL, USA; 3Neonatal Intensive Care Unit, Providence Alaska Medical Center, Anchorage, AK, USA; 4Anesthesiology Department, Central Peninsula Hospital, Soldotna, AK, USACorrespondence: Robert W Arnold, Alaska Blind Child Discovery, Alaska Children’s EYE & Strabismus, 3500 Latouche #280, Anchorage, AK, 99508, USA, Tel +1(907)561-1917, Fax +1(907)563-5373, Email eyedoc@alaska.netPurpose: To better understand the sensory impact of retinal exam components typically experienced by infants undergoing various retinopathy of prematurity staging examinations, adults concerned for infant welfare and exam quality underwent similar exams to compare their perceived stress.Patients and Methods: Adults directly involved with ROP exams and infant stress reduction had cardiac monitoring and concomitant ordinal self symptom-score (1– 10 Likert) during 15 components of the exam including lid speculum, various scleral depressors, indirect ophthalmoscopy, goniolens and direct ophthalmoscopy and retinal photography (Phoenix ICON) with or without topical anesthesia.Results: Nine adults provided impressions and cardiac rhythm gathered supine over 15 minutes. Pain score for topical anesthetic 2 was less than for tropicamide 4. Lid specula numb scored a median 2 level (from 1 to 10) pain but without anesthetic scored 6. The goniolens numb scored 3. Scleral depression numb scored 3– 4 but increased to 7 without topical anesthesia. Direct ophthalmoscope scored 3 through the goniolens and the retinal camera scored 4 pain. Brightness with low 350 Lux indirect scored 6– 8 numb and 9 brightness without anesthetic. Full bright indirect, direct ophthalmoscope and the retinal camera all had Lux of 3000– 4000 and were scored brightness 9, 7 and 10, respectively. Adults had minimal oculocardiac reflex during on-globe retinal examination methods (range 98% to 102%).Conclusion: Topical anesthesia provided a moderate reduction in pain during on-globe lid-speculum, scleral depressed indirect examination. There was a synergistic augmented sensory response between pain and brightness. Adults did not show the bradycardia typically elicited by retinal examinations in premature infants.Keywords: retinopathy of prematurity, infant pain, bradycardia, scleral depression, imaging

The photon-the quantum excitation of the electromagnetic field-is massless but carries momentum. A photon can therefore exert a force on an object upon collision1. Slowing the translational motion of atoms and ions by application of such a force2,3, known as laser cooling, was first demonstrated 40 years ago4,5. It revolutionized atomic physics over the following decades6-8, and it is now a workhorse in many fields, including studies on quantum degenerate gases, quantum information, atomic clocks and tests of fundamental physics. However, this technique has not yet been applied to antimatter. Here we demonstrate laser cooling of antihydrogen9, the antimatter atom consisting of an antiproton and a positron. By exciting the 1S-2P transition in antihydrogen with pulsed, narrow-linewidth, Lyman-α laser radiation10,11, we Doppler-cool a sample of magnetically trapped antihydrogen. Although we apply laser cooling in only one dimension, the trap couples the longitudinal and transverse motions of the anti-atoms, leading to cooling in all three dimensions. We observe a reduction in the median transverse energy by more than an order of magnitude-with a substantial fraction of the anti-atoms attaining submicroelectronvolt transverse kinetic energies. We also report the observation of the laser-driven 1S-2S transition in samples of laser-cooled antihydrogen atoms. The observed spectral line is approximately four times narrower than that obtained without laser cooling. The demonstration of laser cooling and its immediate application has far-reaching implications for antimatter studies. A more localized, denser and colder sample of antihydrogen will drastically improve spectroscopic11-13 and gravitational14 studies of antihydrogen in ongoing experiments. Furthermore, the demonstrated ability to manipulate the motion of antimatter atoms by laser light will potentially provide ground-breaking opportunities for future experiments, such as anti-atomic fountains, anti-atom interferometry and the creation of antimatter molecules.

The positron, the antiparticle of the electron, predicted by Dirac in 1931 and discovered by Anderson in 1933, plays a key role in many scientific and everyday endeavours. Notably, the positron is a constituent of antihydrogen, the only long-lived neutral antimatter bound state that can currently be synthesized at low energy, presenting a prominent system for testing fundamental symmetries with high precision. Here, we report on the use of laser cooled Be+ ions to sympathetically cool a large and dense plasma of positrons to directly measured temperatures below 7 K in a Penning trap for antihydrogen synthesis. This will likely herald a significant increase in the amount of antihydrogen available for experimentation, thus facilitating further improvements in studies of fundamental symmetries.

In 1906, Theodore Lyman discovered his eponymous series of transitions in the extreme-ultraviolet region of the atomic hydrogen spectrum1,2. The patterns in the hydrogen spectrum helped to establish the emerging theory of quantum mechanics, which we now know governs the world at the atomic scale. Since then, studies involving the Lyman-α line-the 1S-2P transition at a wavelength of 121.6 nanometres-have played an important part in physics and astronomy, as one of the most fundamental atomic transitions in the Universe. For example, this transition has long been used by astronomers studying the intergalactic medium and testing cosmological models via the so-called 'Lyman-α forest'3 of absorption lines at different redshifts. Here we report the observation of the Lyman-α transition in the antihydrogen atom, the antimatter counterpart of hydrogen. Using narrow-line-width, nanosecond-pulsed laser radiation, the 1S-2P transition was excited in magnetically trapped antihydrogen. The transition frequency at a field of 1.033 tesla was determined to be 2,466,051.7 ± 0.12 gigahertz (1σ uncertainty) and agrees with the prediction for hydrogen to a precision of 5 × 10-8. Comparisons of the properties of antihydrogen with those of its well-studied matter equivalent allow precision tests of fundamental symmetries between matter and antimatter. Alongside the ground-state hyperfine4,5 and 1S-2S transitions6,7 recently observed in antihydrogen, the Lyman-α transition will permit laser cooling of antihydrogen8,9, thus providing a cold and dense sample of anti-atoms for precision spectroscopy and gravity measurements10. In addition to the observation of this fundamental transition, this work represents both a decisive technological step towards laser cooling of antihydrogen, and the extension of antimatter spectroscopy to quantum states possessing orbital angular momentum.

In 1928, Dirac published an equation 1 that combined quantum mechanics and special relativity. Negative-energy solutions to this equation, rather than being unphysical as initially thought, represented a class of hitherto unobserved and unimagined particles-antimatter. The existence of particles of antimatter was confirmed with the discovery of the positron 2 (or anti-electron) by Anderson in 1932, but it is still unknown why matter, rather than antimatter, survived after the Big Bang. As a result, experimental studies of antimatter3-7, including tests of fundamental symmetries such as charge-parity and charge-parity-time, and searches for evidence of primordial antimatter, such as antihelium nuclei, have high priority in contemporary physics research. The fundamental role of the hydrogen atom in the evolution of the Universe and in the historical development of our understanding of quantum physics makes its antimatter counterpart-the antihydrogen atom-of particular interest. Current standard-model physics requires that hydrogen and antihydrogen have the same energy levels and spectral lines. The laser-driven 1S-2S transition was recently observed 8 in antihydrogen. Here we characterize one of the hyperfine components of this transition using magnetically trapped atoms of antihydrogen and compare it to model calculations for hydrogen in our apparatus. We find that the shape of the spectral line agrees very well with that expected for hydrogen and that the resonance frequency agrees with that in hydrogen to about 5 kilohertz out of 2.5 × 1015 hertz. This is consistent with charge-parity-time invariance at a relative precision of 2 × 10-12-two orders of magnitude more precise than the previous determination 8 -corresponding to an absolute energy sensitivity of 2 × 10-20 GeV.

Antihydrogen, a positron bound to an antiproton, is the simplest anti-atom. Its structure and properties are expected to mirror those of the hydrogen atom. Prospects for precision comparisons of the two, as tests of fundamental symmetries, are driving a vibrant programme of research. In this regard, a limiting factor in most experiments is the availability of large numbers of cold ground state antihydrogen atoms. Here, we describe how an improved synthesis process results in a maximum rate of 10.5 ± 0.6 atoms trapped and detected per cycle, corresponding to more than an order of magnitude improvement over previous work. Additionally, we demonstrate how detailed control of electron, positron and antiproton plasmas enables repeated formation and trapping of antihydrogen atoms, with the simultaneous retention of atoms produced in previous cycles. We report a record of 54 detected annihilation events from a single release of the trapped anti-atoms accumulated from five consecutive cycles.Antihydrogen studies are important in testing the fundamental principles of physics but producing antihydrogen in large amounts is challenging. Here the authors demonstrate an efficient and high-precision method for trapping and stacking antihydrogen by using controlled plasma.

Background:. There is currently a mandate globally to incorporate patient’s perceptions of their illness into outcome measures, in order to provide a deeper insight into medical practice. Facial nerve palsy (FNP) is a devastating condition that can significantly impact quality of life. However, no measure currently exists that comprehensively assesses outcome in FNP using patient perception. The aim of this study is to explore patients’ experiences of FNP with the aim of informing the development of a patient-reported outcome measure. Methods:. Presented is a qualitative study, using in-depth semi-structured interviews with FNP patients. An interview guide was developed using expert opinion and a literature review. Interpretative description was used as the qualitative approach. Interviews were audio-recorded, transcribed, and coded line-by-line. Codes were refined using the constant comparison approach. Interviews continued until data saturation was reached. The data were used to develop a conceptual framework of patient perceived issues relating to FNP. Results:. The sample included 5 men and 9 women aged 57.7 years (range, 36–78) with a range of causes of FNP, including Bell’s palsy (n = 5), acoustic neuroma (n = 3), trauma (n = 2), meningioma (n = 1), muscular dystrophy (n = 1), congenital (n = 1), and Ramsay Hunt syndrome (n = 1). Analysis of the 14 participant interviews led to identification of 5 major domains including “facial function concerns,” “appearance concerns,” “psychological function,” “social function,” and “experience of care.” Conclusion:. This study provides a conceptual framework covering outcomes that matter to patients with FNP, which can be used to inform the development of a new comprehensive FNP-specific patient-reported outcome measure.