Stable, narrow-linewidth laser system with a broad frequency tunability and a fast switching time

For a Rydberg atom-based sensor to change its sensing frequency, the wavelength of the Rydberg state excitation laser must be altered. The wavelength shifts required can be on the order of 10 nm. A fast-tunable narrow-linewidth laser with broadband tuning capability is required. Here, we present a demonstration of a laser system that can rapidly switch a coupling laser as much as 8 nm in less than 50 μs. The laser system comprises a frequency-stabilized continuous wave laser and an electro-optic frequency comb. A filter enables selection of individual comb lines. A high-speed electro-optic modulator is used to tune the selected comb line to a specific frequency, i.e., an atomic transition. Through Rydberg atom-based sensing experiments, we demonstrate frequency hopping between two Rydberg states and a fast switching time of 400 μs, which we show can be reduced to ∼50 μs with a ping-pong scheme. If updating the RF frequency is not required during frequency hopping, a 200 ns switching time can be achieved. These results showcase the potential of the laser system for advanced Rydberg atom-based radio frequency sensing applications, like communications and radar.

Primary standardization and half-life determination of 225Ac at NRC

A solution of 225Ac was standardized by NRC using the triple-to-double coincidence ratio (TDCR) method. The counting efficiencies were calculated assuming a counting efficiency of 100% for alpha decays and those calculated using the MICELLE2 Monte Carlo code for beta decays and was approximately 500% for the NRC TDCR system. The relative uncertainty for the activity concentration was determined to be 0.25%. This agreed with measurements performed using gamma spectroscopy and a predicted calibration factor for the Vinten 671 ionization chamber as calculated using an EGSnrc model, implementing radioactive decay. Finally, the half-life of 225Ac was determined from long-term measurements using ionization chambers and liquid scintillation counting. The NRC measured half-life for 225Ac was found to be 9.914(4) days and is consistent within an expanded uncertainty coverage of k = 2 with the most recent (Kossert et al., 2020; Pommé et al., 2012) measurements of this decay parameter.

Improving Sexual Orientation and Gender Identity Documentation at an NCI-Designated Comprehensive Cancer Center

PURPOSE/OBJECTIVE(S)

To increase the rate of sexual orientation and gender identity (SOGI) patient data collection in healthcare software for new patients at a NCI-Designated Comprehensive Cancer Center, via targeted identification of Advanced Practice Providers (APP), development of novel SOGI collection workflows, creation of a real-time SOGI data dashboard, and tailored training utilizing existing High Reliability Organization (HRO) huddles in order to measure, analyze, and improve the quality of care, safety, and patient experiences for Sexual and Gender Minority (SGM) patients.

MATERIALS/METHODS

Prior to interventions, project leadership (PL) and data analytics staff obtained SOGI baseline data, while cancer center clinical leadership, registration, and administrative staff identified APPs as the most appropriate staff to collect patient SOGI data. Intervention 1: PL met with Disease Management Groups (DMG)/HRO leads of thoracic medical oncology to identify a practice-level APP champion. PL and the APP champion scripted language for multiple scenarios when asking SOGI questions, and served as a resource for additional practice APPs. PL provided SGM-focused training during HRO huddles, which included how to ask and document SOGI, and significance of asking SOGI information. SOGI data completion rate was tracked on a HRO scorecard. This intervention was replicated across additional DMG/HROs during the study period. Intervention 2: Breast surgical oncology completed Intervention 1 and added SOGI questions to their new patient-facing intake form, allowing patients to self-identify. PL and data analytics team provided continuous feedback to DMG/HRO leads on provider-level completion rates and additional education as needed.

RESULTS

At the end of the Interventions, there were 9 LGBTQ+ Knowledge and Awareness HRO training sessions completed resulting in over 300 unique individuals receiving advanced SOGI documentation education. For intervention 1, there were 12,322 new patients asked their SOGI information, which was a greater than 300% increase in SOGI documentation (baseline completion rate for sexual orientation and gender identity was 17% and 21%, respectively, which improved to 77% and 84%). For intervention 2, there were 3,217 new patients asked their SOGI information, which was a greater than 400% increase (baseline completion rate for sexual orientation and gender identity was 13% and 16%, respectively, which improved to 81% and 81%).

CONCLUSION

Together, patient self-reporting quickly increased data completion rates from baseline, comparable to clinical sites from Intervention 1, and may decrease the burden of APPs collecting SOGI history; however, clinical review of questions is important and may further increase SOGI data completion. Leadership buy-in, site champions, and active data monitoring are essential to measurable change. Together, improved SOGI data completion will allow for improved equitable cancer care and increased assessment of SGM cancer disparities.

Childhood-Onset Lupus Nephritis in the Childhood Arthritis and Rheumatology Research Alliance Registry: Short-Term Kidney Status and Variation in Care

OBJECTIVE

The goal was to characterize short-term kidney status and describe variation in early care utilization in a multicenter cohort of patients with childhood-onset systemic lupus erythematosus (cSLE) and nephritis.

METHODS

We analyzed previously collected prospective data from North American patients with cSLE with kidney biopsy-proven nephritis enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from March 2017 through December 2019. We determined the proportion of patients with abnormal kidney status at the most recent registry visit and applied generalized linear mixed models to identify associated factors. We also calculated frequency of medication use, both during induction and ever recorded.

RESULTS

We identified 222 patients with kidney biopsy-proven nephritis, with 64% class III/IV nephritis on initial biopsy. At the most recent registry visit at median (interquartile range) of 17 (8-29) months from initial kidney biopsy, 58 of 106 patients (55%) with available data had abnormal kidney status. This finding was associated with male sex (odds ratio [OR] 3.88, 95% confidence interval [95% CI] 1.21-12.46) and age at cSLE diagnosis (OR 1.23, 95% CI 1.01-1.49). Patients with class IV nephritis were more likely than class III to receive cyclophosphamide and rituximab during induction. There was substantial variation in mycophenolate, cyclophosphamide, and rituximab ever use patterns across rheumatology centers.

CONCLUSION

In this cohort with predominately class III/IV nephritis, male sex and older age at cSLE diagnosis were associated with abnormal short-term kidney status. We also observed substantial variation in contemporary medication use for pediatric lupus nephritis between pediatric rheumatology centers. Additional studies are needed to better understand the impact of this variation on long-term kidney outcomes.

Intraarticular steroids as DMARD-sparing agents for juvenile idiopathic arthritis flares: Analysis of the Childhood Arthritis and Rheumatology Research Alliance Registry

BACKGROUND

Children with juvenile idiopathic arthritis (JIA) who achieve a drug free remission often experience a flare of their disease requiring either intraarticular steroids (IAS) or systemic treatment with disease modifying anti-rheumatic drugs (DMARDs). IAS offer an opportunity to recapture disease control and avoid exposure to side effects from systemic immunosuppression. We examined a cohort of patients treated with IAS after drug free remission and report the probability of restarting systemic treatment within 12 months.

METHODS

We analyzed a cohort of patients from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry who received IAS for a flare after a period of drug free remission. Historical factors and clinical characteristics and of the patients including data obtained at the time of treatment were analyzed.

RESULTS

We identified 46 patients who met the inclusion criteria. Of those with follow up data available 49% had restarted systemic treatment 6 months after IAS injection and 70% had restarted systemic treatment at 12 months. The proportion of patients with prior use of a biologic DMARD was the only factor that differed between patients who restarted systemic treatment those who did not, both at 6 months (79% vs 35%, p < 0.01) and 12 months (81% vs 33%, p < 0.05).

CONCLUSION

While IAS are an option for all patients who flare after drug free remission, it may not prevent the need to restart systemic treatment. Prior use of a biologic DMARD may predict lack of success for IAS. Those who previously received methotrexate only, on the other hand, are excellent candidates for IAS.

An olivine cumulate outcrop on the floor of Jezero crater, Mars

The geological units on the floor of Jezero crater, Mars, are part of a wider regional stratigraphy of olivine-rich rocks, which extends well beyond the crater. We investigate the petrology of olivine and carbonate-bearing rocks of the Séítah formation in the floor of Jezero. Using multispectral images and x-ray fluorescence data, acquired by the Perseverance rover, we performed a petrographic analysis of the Bastide and Brac outcrops within this unit. We find that these outcrops are composed of igneous rock, moderately altered by aqueous fluid. The igneous rocks are mainly made of coarse-grained olivine, similar to some Martian meteorites. We interpret them as an olivine cumulate, formed by settling and enrichment of olivine through multi-stage cooling of a thick magma body.

Social determinants of health influence disease activity and functional disability in Polyarticular Juvenile Idiopathic Arthritis

BACKGROUND

Social determinants of health (SDH) greatly influence outcomes during the first year of treatment in rheumatoid arthritis, a disease similar to polyarticular juvenile idiopathic arthritis (pJIA). We investigated the correlation of community poverty level and other SDH with the persistence of moderate to severe disease activity and functional disability over the first year of treatment in pJIA patients enrolled in the Childhood Arthritis and Rheumatology Research Alliance Registry.

METHODS

In this cohort study, unadjusted and adjusted generalized linear mixed effects models analyzed the effect of community poverty and other SDH on disease activity, using the clinical Juvenile Arthritis Disease Activity Score-10, and disability, using the Child Health Assessment Questionnaire, measured at baseline, 6, and 12 months.

RESULTS

One thousand six hundred eighty-four patients were identified. High community poverty (≥20% living below the federal poverty level) was associated with increased odds of functional disability (OR 1.82, 95% CI 1.28-2.60) but was not statistically significant after adjustment (aOR 1.23, 95% CI 0.81-1.86) and was not associated with increased disease activity. Non-white race/ethnicity was associated with higher disease activity (aOR 2.48, 95% CI: 1.41-4.36). Lower self-reported household income was associated with higher disease activity and persistent functional disability. Public insurance (aOR 1.56, 95% CI 1.06-2.29) and low family education (aOR 1.89, 95% CI 1.14-3.12) was associated with persistent functional disability.

CONCLUSION

High community poverty level was associated with persistent functional disability in unadjusted analysis but not with persistent moderate to high disease activity. Race/ethnicity and other SDH were associated with persistent disease activity and functional disability.

Covid-19, Child & Adolescent Mental Health Services (CAMHS) and Crises

Despite low rates of Covid-19 infection and mortality, children and adolescents have experienced disproportionate restrictions on their personal, social and academic life. Among youth in Ireland, reports of increased attendances by primary care counselling services have been mirrored by increased presentations to emergency departments and specialist mental health services, most notably self-harm and eating disorders. Following an immediate post lock down reduction, emergency department presentations by children for acute mental health care and referrals to child and adolescent mental health services (CAMHS) showed a sustained increase throughout 2020. Urgent action is needed to invest in CAMHS post pandemic to prevent any further increase in psychiatric illness among youth. We all share this collective responsibility to insist of government commitment to our youth.

Short-Term Concerns Primarily Determine Patient Preference for Abdominal Aortic Aneurysm Repair

INTRODUCTION

Abdominal aortic aneurysm (AAA) repair may be performed through open or endovascular approaches, but the factors influencing a patient's repair-type preference are not well characterized. Here we performed a qualitative analysis to better understand factors influencing patient preference within the Preference for Open Versus Endovascular Repair of AAA Trial.

METHODS

Open-ended responses regarding primary (n = 21) and secondary (n = 47) factors influencing patient preference underwent qualitative analysis using the constant comparative method with iterative reviews. Codes were used to generate themes and themes grouped into categories, with each step conducted via consensus agreement between three researchers. Relative prevalence of themes were compared to ascertain trends in patient preference.

RESULTS

Patient responses regarding both primary and secondary factors fell into four categories: Short-term concerns, long-term concerns, advice & experience, and other. Patients most frequently described short-term concerns (23) as their primary influence, with themes including post-op complications, hospitalization & recovery, and intraoperative concerns. Long-term concerns were more prevalent (20) as secondary factors, which included themes such as survival, and chronic management. The average age of patients voicing only long-term concerns as a primary factor was 11 years younger than those listing only short-term concerns.

CONCLUSION

Short-term concerns relating to the procedure and recovery are more often the primary factor influencing patient preference, while long term concerns play a more secondary role. Long-term concerns are more often a primary factor in younger patients. Vascular surgeons should consider this information in shared decision making to reach an optimal outcome.

Rapid review of decision-making for place of care and death in older people: Lessons for COVID-19

Introduction

The coronavirus pandemic (COVID-19) has affected the functioning and capacity of healthcare systems worldwide. COVID-19 has also disproportionately affected older adults, including those living with dementia. In the context of COVID-19, decision-making surrounding place of care and place of death in this population involves significant new challenges.

Objectives

To explore key factors that influence place of care and place of death decisions in older adults. A secondary aim was to investigate key factors that influence the process and outcome of these decisions in older adults. To apply findings from current evidence to the context of COVID-19.

Methods

Rapid review of reviews, undertaken using WHO guidance for rapid reviews. Ten papers were included for full data extraction. These papers were published between 2005-2020. Data extracted was synthesised using narrative synthesis, with thematic analysis and tabulation.

Results

Papers included discussed actual place of death, as well as preferred. Results were divided into papers that explored the process of decision-making, and those that explored decision-making outcomes. Factors such as caregiver capacity, the availability of multidisciplinary teams, cultural appropriateness of care packages and advanced care planning were found to be key.

Conclusions

The process and outcomes of decision-making for older people are affected by many factors – all of which have the potential to influence both patients and caregivers experience of illness and dying. Within the context of COVID-19, such decisions may have to be made rapidly and be reflexive to changing needs of systems and of families and patients.

Neutrophil-Lymphocyte Ratio and Absolute Lymphocyte Count as Prognostic Markers in Patients Treated with Curative-intent Radiotherapy for Non-small Cell Lung Cancer

AIMS

The neutrophil-lymphocyte ratio (NLR) and the absolute lymphocyte count (ALC) have been proposed as prognostic markers in non-small cell lung cancer (NSCLC). The objective of this study was to examine the association of NLR/ALC before and after curative-intent radiotherapy for NSCLC on disease recurrence and overall survival.

MATERIALS AND METHODS

A retrospective study of consecutive patients who underwent curative-intent radiotherapy for NSCLC across nine sites in the UK from 1 October 2014 to 1 October 2016. A multivariate analysis was carried out to assess the ability of pre-treatment NLR/ALC, post-treatment NLR/ALC and change in NLR/ALC, adjusted for confounding factors using the Cox proportional hazards model, to predict disease recurrence and overall survival within 2 years of treatment.

RESULTS

In total, 425 patients were identified with complete blood parameter values. None of the NLR/ALC parameters were independent predictors of disease recurrence. Higher pre-NLR, post-NLR and change in NLR plus lower post-ALC were all independent predictors of worse survival. Receiver operator curve analysis found a pre-NLR > 2.5 (odds ratio 1.71, 95% confidence interval 1.06-2.79, P < 0.05), a post-NLR > 5.5 (odds ratio 2.36, 95% confidence interval 1.49-3.76, P < 0.001), a change in NLR >3.6 (odds ratio 2.41, 95% confidence interval 1.5-3.91, P < 0.001) and a post-ALC < 0.8 (odds ratio 2.86, 95% confidence interval 1.76-4.69, P < 0.001) optimally predicted poor overall survival on both univariate and multivariate analysis when adjusted for confounding factors. Median overall survival for the high-versus low-risk groups were: pre-NLR 770 versus 1009 days (P = 0.34), post-NLR 596 versus 1287 days (P ≤ 0.001), change in NLR 553 versus 1214 days (P ≤ 0.001) and post-ALC 594 versus 1287 days (P ≤ 0.001).

CONCLUSION

NLR and ALC, surrogate markers for systemic inflammation, have prognostic value in NSCLC patients treated with curative-intent radiotherapy. These simple and readily available parameters may have a future role in risk stratification post-treatment to inform the intensity of surveillance protocols.

Rapid development of a decision-aid for people with dementia and their families during COVID-19

Introduction

COVID-19 as a pandemic has disproportionately affected older adults, including those with dementia. The effects on health and social care systems has necessitated a rapid-response approach to care planning and decision-making in this population, with reflexivity and responsiveness to changing individual and system needs at its core. In light of this, a decision-making tool to help families of persons with dementia was developed using a combination of qualitative data and evidence synthesis.

Objectives

To develop a decision-aid using a combination of assessment and evidence-gathering methods for families of persons with dementia.

Methods

Semi-structured interviews with helpline staff from national end-of-life and supportive care organisations formed the basis of the tool design. Co-design with people living with dementia, current and former carers and experts in general practice and social care shaped the next stage. Simultaneously, a rapid review of current evidence on making decisions with older people at the end of life was undertaken.

Results

Output from interviews covered many topics, including trust, agency and confusion in making decisions in the context of COVID-19. The rapid review of existing evidence highlighted the need to consider both process and outcome elements of decision-making.

Conclusions

Combining different sources and forms of evidence was efficient and valuable in creating a novel decision-making tool for persons with dementia and their families within the context of COVID-19. The decision-aid covered care planning, caregiver support systems, access to information and contingency considerations. Upon publication, the tool was adopted by NHS England and other leading healthcare organisations.

Disclosure

No significant relationships.

Predicting the Risk of Disease Recurrence and Death Following Curative-intent Radiotherapy for Non-small Cell Lung Cancer: The Development and Validation of Two Scoring Systems From a Large Multicentre UK Cohort

AIMS

There is a paucity of evidence on which to produce recommendations on neither the clinical nor the imaging follow-up of lung cancer patients after curative-intent radiotherapy. In the 2019 National Institute for Health and Care Excellence lung cancer guidelines, further research into risk-stratification models to inform follow-up protocols was recommended.

MATERIALS AND METHODS

A retrospective study of consecutive patients undergoing curative-intent radiotherapy for non-small cell lung cancer from 1 October 2014 to 1 October 2016 across nine UK trusts was carried out. Twenty-two demographic, clinical and treatment-related variables were collected and multivariable logistic regression was used to develop and validate two risk-stratification models to determine the risk of disease recurrence and death.

RESULTS

In total, 898 patients were included in the study. The mean age was 72 years, 63% (562/898) had a good performance status (0-1) and 43% (388/898), 15% (134/898) and 42% (376/898) were clinical stage I, II and III, respectively. Thirty-six per cent (322/898) suffered disease recurrence and 41% (369/898) died in the first 2 years after radiotherapy. The ASSENT score (age, performance status, smoking status, staging endobronchial ultrasound, N-stage, T-stage) was developed, which stratifies the risk for disease recurrence within 2 years, with an area under the receiver operating characteristic curve (AUROC) for the total score of 0.712 (0.671-0.753) and 0.72 (0.65-0.789) in the derivation and validation sets, respectively. The STEPS score (sex, performance status, staging endobronchial ultrasound, T-stage, N-stage) was developed, which stratifies the risk of death within 2 years, with an AUROC for the total score of 0.625 (0.581-0.669) and 0.607 (0.53-0.684) in the derivation and validation sets, respectively.

CONCLUSIONS

These validated risk-stratification models could be used to inform follow-up protocols after curative-intent radiotherapy for lung cancer. The modest performance highlights the need for more advanced risk prediction tools.

An evaluation of a veterinary-specific mental health service

BACKGROUND

Veterinary professionals are at increased risk of suicide and mental health difficulties compared to the general population. Vetlife Health Support (VHS) is a mental health case management service for veterinarians with mental health difficulties.

AIMS

To evaluate the VHS case management service from the service user's perspective.

METHODS

Service users (n = 98) completed questionnaires assessing their experience with VHS and current mental health status using the Kessler-6 Scale. A sub-sample was interviewed and the data qualitatively analysed (n = 14).

RESULTS

The results show that 97% (n = 95) reported a positive experience with VHS and 98% (n = 96) reported VHS staff respected and listened to them. Participants reported significant improvements in relationships with others after VHS (P < 0.001) and were significantly more likely to be in receipt of formal mental health care after VHS than before (P < 0.01). The main emergent themes from the qualitative interviews were (i) positive communication between clinician and service users, (ii) veterinary-specific mental health services were regarded as important to understanding service users' circumstances, (iii) knowing someone is supporting them positively impacted wellbeing and (iv) confusion with discharge status.

CONCLUSIONS

Most participants reported positive experiences with VHS. Quantitatively, data showed that participants reported significant improvements in relationships and access to formal mental health care after contact with VHS. Interviews with service users revealed that they felt speaking to a mental health professional with veterinary-specific knowledge was beneficial for their wellbeing. Further evaluation assessing whether VHS leads to a measurable impact on psychological wellbeing is recommended.

Loss of the laminin subunit alpha-3 induces cell invasion and macrophage infiltration in cutaneous squamous cell carcinoma

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is a common cancer that invades the dermis through the basement membrane. The role of the basement membrane in poorly differentiated cSCC is not well understood.

OBJECTIVES

To study the effect that loss of the laminin subunit alpha-3 (α3) chain from the tumour microenvironment has on tumour invasion and inflammatory cell recruitment.

METHODS

We examined the role of the basement membrane proteins laminin subunits α3, β3 and γ2 in SCC invasion and inflammatory cell recruitment using immunohistochemistry, short hairpin RNA knockdown, RNA-Seq, mouse xenograft models and patient tumour samples.

RESULTS

Analysis of SCC tumours and cell lines using antibodies specific to laminin chains α3, β3 and γ2 identified a link between poorly differentiated SCC and reduced expression of laminin α3 but not the other laminin subunits investigated. Knockdown of laminin α3 increased tumour invasion both in vitro and in vivo. Western blot and immunohistochemical staining identified increased phosphorylated myosin light chain with loss of laminin α3. Inhibition of ROCK (rho-associated protein kinase) but not Rac1 significantly reduced the invasive potential of laminin α3 knockdown cells. Knockdown of laminin subunits α3 and γ2 increased monocyte recruitment to the tumour microenvironment. However, only the loss of laminin α3 correlated with increased tumour-associated macrophages both in xenografted tumours and in patient tumour samples.

CONCLUSIONS

These data provide evidence that loss of the laminin α3 chain in cSCC has an effect on both the epithelial and immune components of cSCC, resulting in an aggressive tumour microenvironment.

Absence of the Musculocutaneous Nerve and Associated Compensation by the Median Nerve

The musculocutaneous and median nerves frequently show variations from their normal course. The purpose of this paper is to report a rare variation, in which the right musculocutaneous nerve was absent. Consequently, the median nerve supplied motor innervation to the flexor compartment of the arm and sensory innervation to the lateral aspect of the forearm. The primary targets of this paper are orthopedic surgeons, anesthesiologists and radiologists. In cases of injuries to the upper limb, knowledge of these variations can assist them in avoiding misdiagnoses.

The logistical management of tertiary urethral disease in the United Kingdom: Implications from an online audit of male reconstructive urethral surgery

Objective:

To determine those patient groupings, based on volume and risk, whose optimal urethral reconstructive management might be provided by a reorganisation of UK reconstructive surgeons.

Methods:

Between 2010 and 2017, ~689 men/year were enrolled onto an online audit platform collecting data about urethral reconstruction in the UK; this accrual was compared against hospital episode statistics (HES). The available workforce, and where this was based, was collected. Individual and institutional incumbent patient volumes, pathology, surgical complexity and outcomes from treatment were collated to stratify volume/risk groups.

Results:

More than 90% of all HES-recorded data were accrued, being provided by 50 surgeons at 39 operative sites. Most reconstructive surgery was provided at 10 centres performing >20 procedures/year. More than 50% of all interventions were of a high-volume low-risk type. Of activity, 32.3% was intermediate volume or moderate risk, and 12.5% of men presented for lower-volume or higher-risk procedures.

Conclusion:

Correlation of detailed volume/outcome data allows the definition of patient populations presenting for urethral reconstruction. Stratification of each group’s management, to optimise the surgical outcome, may be applied to a hierarchical service delivery model based on the complexity of the patient’s presenting urethral pathology.

Level of evidence:

Level IV

Rapid polarization mapping in ferroelectrics using Fourier masking

Ferroelectric materials, and more specifically ferroelectric domain walls (DWs) have become an area of intense research in recent years. Novel physical phenomena have been discovered at these nanoscale topological polarization discontinuities by mapping out the polarization in each atomic unit cell around the DW in a scanning transmission electron microscope (STEM). However, identifying these features requires an understanding of the polarization in the overall domain structure of the TEM sample, which is often a time-consuming process. Here, a fast method of polarization mapping in the TEM is presented, which can be applied to a range of ferroelectric materials. Due to the coupling of polarization to spontaneous strain, we can isolate different strain states and demonstrate the fast mapping of the domain structure in ferroelectric lead titanate (PTO). The method only requires a high-resolution TEM or STEM image and is less sensitive to zone axis or local strain effects, which may affect other techniques. Thus, it is easily applicable to in-situ experiments. The complimentary benefits of Fourier masking with more advanced mapping strategies and its application to other materials are discussed. These results imply that Fourier masked polarization mapping will be a useful tool for electron microscopists in streamlining their analysis of ferroelectric TEM samples. LAY DESCRIPTION: This paper addresses a problem that often occurs when looking at a ferroelectric material in the Transmission Electron Microscope (TEM). Ferroelectric samples are interesting because they form tiny areas inside themselves with arrow of charge in each one. The thinner the sample, the smaller these regions, called "domains" become. These arrows of charge point in different directions in each domain of the sample. The boundary where these domains meet have interesting properties to study in a TEM but it's important to figure out which way the arrows point in the domains around the boundary. What causes the arrows in the different domains is tiny shifts of different atoms in unit cell away from their neutral position, usually because they're being squeezed by pressure from the domains nearby. The problem is that these tiny atoms moving are difficult to measure and see where the charged arrow is pointing, often it's hard to know how many different domains are even in the sample and where they begin. This paper discusses a method called "Fourier masking" to quickly see what's going on in the overall TEM sample, where the domains are and roughly where the arrows point. It does this by looking at the spacings of the atoms from a magnification where you can just about see the lines of atoms. In lead titanate the unit cell is a rectangle and the arrow always points in line with the long side of the rectangle. The Fourier masking lets you see which direction the long side of the rectangular unit cell is pointing in different parts of your TEM image. The big advantage is that it takes about two minutes to do and uses software that almost every TEM already has. That lets the TEM user quickly know where the domains are in their TEM samples and roughly which way the arrows of charge are pointing. Then they can choose the most interesting features focus on for higher resolution analysis.

Toxicity and Efficacy of Stereotactic Ablative Body Radiotherapy for Moderately Central Non-small Cell Lung Cancers Using 50 Gy in Five Fractions

AIMS

Stereotactic ablative body radiotherapy doses for peripheral lung lesions caused high toxicity when used for central non-small cell lung cancer (NSCLC). To determine a safe stereotactic ablative body radiotherapy dose for central tumours, the phase I/II Radiation Therapy Oncology Group RTOG 0813 trial used 50 Gy/five fractions as a baseline. From 2013, 50 Gy/five fractions was adopted at the Beatson West of Scotland Cancer Centre for inoperable early stage central NSCLC. We report our prospectively collected toxicity and efficacy data.

MATERIALS AND METHODS

Patient and treatment characteristics were obtained from electronic medical records. Tumours were classed as moderately central or ultra-central tumours using published definitions. Toxicity was assessed in a centralised follow-up clinic at 2 weeks, 6 weeks, 3 months, 6 months, 1 year and 2 years after treatment.

RESULTS

Fifty patients (31 women, 19 men, median age 75.1 years) were identified with T1-2N0M0 moderately central NSCLC; one patient had both an ultra-central and a moderately central tumour. Eighty-four per cent were medically unfit for surgery. Forty per cent had biopsy-proven NSCLC and 60% were diagnosed radiologically using 18-fluorodeoxyglucose positron emission tomography/computed tomography imaging. Fifty-six per cent of patients were Eastern Cooperative Oncology Group (ECOG) performance status 2 or worse. All patients received 50 Gy/five fractions on alternate days on schedule. Two patients died within 90 days of treatment, one from a chest infection, the other cause of death was unknown. There was one episode of early grade 3 oesophagitis and one grade 3 late dyspnoea. There was no grade 4 toxicity. Over a median follow-up of 25.2 months (range 1-70 months), there were 34 deaths: 18 unrelated to cancer and 16 due to cancer recurrence. The median overall survival was 27.0 months (95% confidence interval 20.6-35.9) and cancer-specific survival was 39.8 months (95% confidence interval 28.6, not reached).

CONCLUSION

This study has shown that 50 Gy/five fractions is a safe dose and fractionation for early stage inoperable moderately central NSCLC, with outcomes comparable with other series, even with patients with a poor performance status.

Production of a carrier-free standard 56Mn source for the NRC manganese salt bath

The National Research Council (NRC) of Canada's primary method for emission rate for radionuclide neutron sources utilizes a manganese salt bath which was last calibrated in the 1960s. At that time, an NRC RaBe neutron source was used to irradiate a solution of calcium permanganate to take advantage of the Szilard-Chalmers effect in producing the bulk ⁵⁶Mn material for standardization and calibration of the bath. When attempting to repeat this exercise, a small amount (~100 kBq) was produced. This amount was sufficient for the standardization process but did not yield enough material to calibrate the bath to a sufficient level of precision. Improvements upon the previous separation scheme adopted at NRC for the separation of the ⁵⁶Mn from the bulk irradiated material included the rinsing of the ⁵⁶Mn dioxide precipitate using a mixture of sulfuric acid and hydrogen peroxide. While these improvements made in the separation chemistry improved the yield of ⁵⁶Mn extraction from 60% to above 95% the maximum amount of activity was still quite low. Hence in March of 2018, the SLOWPOKE-2 Facility at the Royal Military College in Kingston, ON, was used to irradiate three vials of KMnO₄ in solution. An estimated 2 GBq was produced and sent to NRC, from which the extraction procedure recovered essentially all of the available ⁵⁶Mn. The ⁵⁶Mn was standardized using the 4πβ-γ anti-coincidence counting system and confirmed using the CIEMAT/NIST primary method. The resulting bulk material was certified with an uncertainty of 0.8% (k = 2). Minor quantities of ⁶⁵Zn, ^69mZn and ⁴²K were unexpectedly observed but were in minute quantities so as not to affect the results of the standardization or calibration. The standardized ⁵⁶Mn artifact was used to calibrate the Secondary Standard Ionizing Radiation Chamber System (SSIRCS) for a more rapid deployment of the calibrant in the future.