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Despite the widespread use of Scanning Transmission Electron Microscopy (STEM) for observing the structure of materials at the atomic scale, a detailed understanding of some relevant electron beam damage mechanisms is limited. Recent reports suggest that certain types of damage can be modelled as a diffusion process and that the accumulation effects of this process must be kept low in order to reduce damage. We therefore develop an explicit mathematical formulation of spatiotemporal diffusion processes in STEM that take into account both instrument and sample parameters. Furthermore, our framework can aid the design of Diffusion Controlled Sampling (DCS) strategies using optimally selected probe positions in STEM, that constrain the cumulative diffusion distribution. Numerical simulations highlight the variability of the cumulative diffusion distribution for different experimental STEM configurations. These analytical and numerical frameworks can subsequently be used for careful design of 2- and 4-dimensional STEM experiments where beam damage is minimised.
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Here we show that compressive sensing allows 4-dimensional (4-D) STEM data to be obtained and accurately reconstructed with both high-speed and reduced electron fluence. The methodology needed to achieve these results compared to conventional 4-D approaches requires only that a random subset of probe locations is acquired from the typical regular scanning grid, which immediately generates both higher speed and the lower fluence experimentally. We also consider downsampling of the detector, showing that oversampling is inherent within convergent beam electron diffraction (CBED) patterns and that detector downsampling does not reduce precision but allows faster experimental data acquisition. Analysis of an experimental atomic resolution yttrium silicide dataset shows that it is possible to recover over 25 dB peak signal-to-noise ratio in the recovered phase using 0.3% of the total data. Lay abstract: Four-dimensional scanning transmission electron microscopy (4-D STEM) is a powerful technique for characterizing complex nanoscale structures. In this method, a convergent beam electron diffraction pattern (CBED) is acquired at each probe location during the scan of the sample. This means that a 2-dimensional signal is acquired at each 2-D probe location, equating to a 4-D dataset. Despite the recent development of fast direct electron detectors, some capable of 100kHz frame rates, the limiting factor for 4-D STEM is acquisition times in the majority of cases, where cameras will typically operate on the order of 2kHz. This means that a raster scan containing 256^2 probe locations can take on the order of 30s, approximately 100-1000 times longer than a conventional STEM imaging technique using monolithic radial detectors. As a result, 4-D STEM acquisitions can be subject to adverse effects such as drift, beam damage, and sample contamination. Recent advances in computational imaging techniques for STEM have allowed for faster acquisition speeds by way of acquiring only a random subset of probe locations from the field of view. By doing this, the acquisition time is significantly reduced, in some cases by a factor of 10-100 times. The acquired data is then processed to fill-in or inpaint the missing data, taking advantage of the inherently low-complex signals which can be linearly combined to recover the information. In this work, similar methods are demonstrated for the acquisition of 4-D STEM data, where only a random subset of CBED patterns are acquired over the raster scan. We simulate the compressive sensing acquisition method for 4-D STEM and present our findings for a variety of analysis techniques such as ptychography and differential phase contrast. Our results show that acquisition times can be significantly reduced on the order of 100-300 times, therefore improving existing frame rates, as well as further reducing the electron fluence beyond just using a faster camera.
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Traditional image acquisition for cryo focused ion-beam scanning electron microscopy (FIB-SEM) tomography often sees thousands of images being captured over a period of many hours, with immense data sets being produced. When imaging beam sensitive materials, these images are often compromised by additional constraints related to beam damage and the devitrification of the material during imaging, which renders data acquisition both costly and unreliable. Subsampling and inpainting are proposed as solutions for both of these aspects, allowing fast and low-dose imaging to take place in the Focused ion-beam scanning electron microscopy FIB-SEM without an appreciable loss in image quality. In this work, experimental data are presented which validate subsampling and inpainting as a useful tool for convenient and reliable data acquisition in a FIB-SEM, with new methods of handling three-dimensional data being employed in the context of dictionary learning and inpainting algorithms using a newly developed microscope control software and data recovery algorithm.
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Scanning transmission electron microscopy images can be complex to interpret on the atomic scale as the contrast is sensitive to multiple factors such as sample thickness, composition, defects and aberrations. Simulations are commonly used to validate or interpret real experimental images, but they come at a cost of either long computation times or specialist hardware such as graphics processing units. Recent works in compressive sensing for experimental STEM images have shown that it is possible to significantly reduce the amount of acquired signal and still recover the full image without significant loss of image quality, and therefore it is proposed here that similar methods can be applied to STEM simulations. In this paper, we demonstrate a method that can significantly increase the efficiency of STEM simulations through a targeted sampling strategy, along with a new approach to independently subsample each frozen phonon layer. We show the effectiveness of this method by simulating a SrTiO3 grain boundary and monolayer 2H-MoS2 containing a sulphur vacancy using the abTEM software. We also show how this method is not limited to only traditional multislice methods, but also increases the speed of the PRISM simulation method. Furthermore, we discuss the possibility for STEM simulations to seed the acquisition of real data, to potentially lead the way to self-driving (correcting) STEM.
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BACKGROUND: In Australia, midwives care closely for women during pregnancy and birth and the immediate postnatal period. This scoping review aimed to explore the experiences of female maternity healthcare professionals when they return to work following a personal pregnancy loss or neonatal death.Methodology: A scoping review was carried out on published and unpublished research and grey literature looking at how maternity healthcare professionals who have had a personal perinatal loss experience working in a maternity setting following the loss. A search of the literature was performed between October and December 2018, with no set limitations. A search for relevant references from included papers was also carried out. The literature was analysed thematically. The types of perinatal loss were defined as per Australian guidelines. RESULTS: 10 articles were included in this scoping review. Four themes emerged from the literature and these were: 1) Impact of being asked, "have you got children?"; 2) Impact on professional practice; 3) Impact of pre-existing professional knowledge; 4) Importance of collegial support on return to work. CONCLUSIONS: Return to work in a maternity setting following a personal perinatal loss is emotionally challenging and requires a range of supports. Further research is needed in this area.
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Tocologia , Recém-Nascido , Criança , Humanos , Feminino , Gravidez , Austrália , Pessoal de Saúde/psicologia , Atenção à SaúdeRESUMO
When high-energy electrons from a scanning transmission electron microscope (STEM) are incident on a liquid, the vast majority of the chemical reactions that are observed are induced by the radiolysis breakdown of the liquid molecules. In the study of liquids, the radiolysis products of pure water are well known, and their rate of formation for a given flux of high-energy electrons has been studied intensively over the last few years for uniform TEM illumination. In this paper, we demonstrate that the temporal and spatial distribution of the electron illumination can significantly affect the final density of radiolysis products in water and even change the type of reaction taking place. We simulate the complex array of possible spatial/temporal distributions of electrons that are accessible experimentally by controlling the size, the scan rate and the hopping distance of the electron probe in STEM mode and then compare the results to the uniformly illuminated TEM mode of imaging. By distributing the electron dose both spatially and temporally in the STEM through a randomised "spot-scan" mode of imaging, the diffusion overlap of the radiolysis products can be reduced, and the resulting reactions can be more readily controlled. This control allows the resolution of the images to be separated from the speed of the induced reaction (which is based on beam current alone) and this facet of the experiment will allow a wide range of chemical reactions to be uniquely tailored and observed in all liquid cell STEM experiments.
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AIMS AND OBJECTIVES: This article presents the generation of a model of care encompassing "function" and "affect" based on findings from a 2011 research project aimed at improving care delivery for people with advanced dementia. Objectives were to provide comprehensive and sustainable care, honouring and respecting the person. BACKGROUND: Dementia is a debilitating, progressive, and terminal disease with a trajectory ranging from approximately 3 to 16 years, yet attention to end-of-life care, promoting comfort, alleviating suffering, and maximizing quality of life is frequently overlooked for people living in the advanced stages of the disease. METHODS: The research project from which the model was drawn used a three-phase mixed methods approach at three residential aged care facilities (nursing homes) providing high care in New South Wales, Australia. Thematic analysis was elicited from focus group discussions with staff, family members, and carers of residents. FINDINGS: Themes describe distinct dimensions of a model of care: "function" (dedication, designation, and deliberation) and "affect" (the personal outcomes revealed in relaxation, stimulation, and transformation). CONCLUSION: Reframing nursing practice from task and disease orientation to person centred and relationship focused is essential in meeting the complete needs of people with advanced dementia. This transformational model of care may be useful in adapting to other end-of-life care settings.
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Afeto , Demência/psicologia , Modelos de Enfermagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Cuidadores/psicologia , Coleta de Dados , Atenção à Saúde , Demência/enfermagem , Família/psicologia , Feminino , Grupos Focais , Humanos , Masculino , Pessoa de Meia-Idade , New South Wales , Casas de Saúde/organização & administração , Qualidade de Vida , Assistência TerminalRESUMO
Amorphous spray-dried dispersions (SDDs) are a key enabling technology for oral solid dosage formulations, used to improve dissolution behaviour and clinical exposure of poorly soluble active pharmaceutical ingredients (APIs). Appropriate assessment of amorphous dissolution mechanisms is an ongoing challenge. Here we outline the novel application using focused beam reflectance measurement (FBRM) to analyse particle populations orthogonal to USP 2 dissolution. The relative impact of polymer substitution and particle attributes on 25% BMS-708163/HPMC-AS SDD dissolution was assessed. Dissolution mechanisms for SDDs were categorized into erosion versus disintegration. Beyond an initial mixing period, FBRM particle counts diminish slowly and particles are detectable until the point where API dissolution is complete. There is correlation between FBRM particle count decay rate, representing loss of SDD particles in the dissolution media, and UV dissolution rate, measuring dissolved API. For the SDD formulation examined, the degree of succinoyl substitution for HPMC-AS, SDD particle size and surface area all had an impact on dissolution. These data indicate the SDD displayed an erosion mechanism and that FBRM is capturing a rate-limiting step. From this screening tool, the mechanistic understanding and measured impact of polymer chemistry and particle properties can inform a risk-assessment and control strategy for this compound.
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Excipientes/química , Lactose/análogos & derivados , Metilcelulose/análogos & derivados , Oxidiazóis/química , Sulfonamidas/química , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Química Farmacêutica/instrumentação , Desenho de Equipamento , Lactose/química , Metilcelulose/química , Tamanho da Partícula , SolubilidadeRESUMO
AIMS AND OBJECTIVES: To investigate the feasibility of a 13-week mentoring programme in providing social support to promote hope for recovery in anorexia nervosa. BACKGROUND: With no clear first-line psychological treatment for people with anorexia nervosa, mentoring support programmes, as an adjunct to treatment, may provide the social support necessary to promote hope for recovery. DESIGN: A mixed-method study; participatory action research. METHODS: Women (n = 11), recovering and who had recovered from anorexia nervosa, participated in the programme and completed self-report questionnaires related to quality of life, distress and the mentoring relationship at different time points. Qualitative feedback from logbooks, workshop evaluation questionnaires, interviews and focus groups was also collected to assess the programme's acceptability. RESULTS: General compliance for completing most study outcome questionnaires was 90%; however, the mentoring relationship questionnaires were not completed to the same degree. Five key themes emerged from the focus group/interview data: (i) she understands me and could relate to me; (ii) reconnecting with the world-asking questions and being challenged; (iii) mentors' altruistic motivations and the transformation and discovery of self; (iv) instilling hope-recovery is possible; and (v) effective communication-the key to successful mentoring. CONCLUSIONS: Further research is needed; however, the results provide preliminary support for the mentoring programme's feasibility as an adjunct to treatment. We found that having someone who understands, to talk and share with, met a clear need for people with anorexia nervosa. RELEVANCE TO CLINICAL PRACTICE: While further research is warranted mentoring support or recovered mentors, may play a potentially valuable role in supporting those in community settings.
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Anorexia Nervosa/terapia , Tutoria , Qualidade de Vida , Adulto , Anorexia Nervosa/psicologia , Estudos de Viabilidade , Feminino , Grupos Focais , Pesquisa sobre Serviços de Saúde , Esperança , Humanos , Pesquisa Qualitativa , Autorrelato , Apoio SocialRESUMO
AIM: To discuss the application of the principles of participatory action research (PAR) in a project that developed and evaluated a mentor-mentee support programme for women with anorexia nervosa. BACKGROUND: A programme was developed and implemented in which mentors and mentees participated in workshops, social activities and focus groups that sought to support and develop resilience for those experiencing anorexia nervosa. DISCUSSION: PAR principles were mirrored in the programme, paying respect to the views and needs of each participant, an open trajectory to possible conclusions and a continuous feedback cycle. Mentees had a sense of empowerment, ownership of the programme and hope that recovery was possible. It allowed their voices to be heard and provided them with belief they could begin new relationships and friendships. CONCLUSION: The principles of PAR suited a project aimed at developing self-determination and resilience in women with anorexia nervosa. IMPLICATIONS FOR RESEARCH/PRACTICE: PAR would be readily transferable to a number of mental health settings where empowerment is of paramount concern.
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Anorexia Nervosa/fisiopatologia , Pesquisa sobre Serviços de Saúde , Feminino , HumanosRESUMO
AIM: This study analysed historical healthcare records to investigate how women diagnosed with mania or psychosis and admitted to two mental health facilities in Australia following childbirth, were described in the late Victorian (1885-1895) and inter-war period (1925-1935). BACKGROUND: Although historians have examined the history of mental health systems in Australia, there is no published scholarship that considers the healthcare records of these women. This was a unique opportunity to explore these documents. DESIGN: An historical study examining healthcare records. The data collection occurred in 2012. METHODS: Women admitted to mental health facilities with a diagnosis of psychosis or mania were identified in the admission registers found in the State Record Office of New South Wales and, if available, their healthcare record was transcribed verbatim. The records were imported into NVivo 10 for content analysis to determine the range and scope of information. A further textual analysis was conducted to see if the woman's diagnosis was congruent with the outcome of her admission. RESULTS/FINDINGS: 155 cases were identified across the two periods. Although, demographic data and the description of the women on admission were remarkably similar, 17% of women were physically, rather than mentally, ill and died soon after admission. The findings demonstrate the importance of current practices such as taking a comprehensive healthcare assessment and the use of antibiotics and sanitary measures during labour and in the postnatal period. CONCLUSION: Historical investigations of healthcare records provide legitimacy for current healthcare practices.
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Serviço Hospitalar de Admissão de Pacientes/história , Transtorno Bipolar/história , Hospitais Psiquiátricos/história , Prontuários Médicos , Serviços de Saúde Mental/história , Parto/psicologia , Transtornos Psicóticos/história , Adulto , Feminino , História do Século XIX , História do Século XX , Humanos , New South Wales , Gravidez , Adulto JovemRESUMO
This article presents the mental health aspects of 'touch' associated with a funded research project: Avoiding 'high tech' through 'high touch' in end-stage dementia: Protocol for care at the end-of-life. These mental health aspects highlight the human need for touch that continues up until and inclusive of the final stages of life. This study was informed by Simard's (2007) 'high touch' protocol based on the End-of-Life Namaste Care programme for people with dementia. The article is situated in relation to the research project which used a three-phase mixed methods approach. Data explored in this article are derived from focus groups conducted at three residential aged care facilities located in metropolitan and regional areas of NSW, Australia. The exploration of touch vis-a-vis mental health fell under two broad themes: touch by others and touch by the person. Sub-elements of these themes comprised touch towards a physical objective, touch towards an emotional objective, touch of objects and touch of others. The overarching outcome of interconnectedness embraced environmental awareness and human and life awareness. These two broad themes, with their accompanying elements, express the essential nature of mental health as a reciprocal connectedness, with reciprocal impacts on both those people with advanced dementia and their carers.
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Demência/terapia , Assistência Terminal/métodos , Toque Terapêutico , Feminino , Grupos Focais , Humanos , Masculino , New South Wales , Pesquisa QualitativaRESUMO
AIMS AND OBJECTIVES: This study presents a minimum data set designed for an electronic system to complement verbal nursing handover. Background. Poor communication of patient information at handover has been implicated in adverse events with changes to clinical handover being proposed as a solution. This study developed a minimum data set for an electronic patient summary tool. DESIGN; Using an observational design the scope of information being presented by nurses at handover was identified in relation to a generic Nursing Handover Minimum Data Set. METHOD: Patient handovers (n = 195) were observed and digitally recorded across diverse specialties. RESULTS: Content analysis confirmed the frequent use of the Nursing Handover Minimum Data Set items across all specialties. The use of the items was affected by the patient context and the clinical setting. Aged care patients often had several clinical alerts reported (pressure areas, falls risk). Rapid changes in patient condition in emergency emphasised the need for a focus on observations and presenting problems. Mental health and maternity required further refinement of the items. CONCLUSION: The generic Nursing Handover Minimum Data Set can direct nurses to give a comprehensive account of their patient's condition and care. The data set needs to be flexible and adaptable to the patient context and setting and complements structured content verbal handover. This minimum data set provides an excellent framework for system development by clinicians, managers and information technologists. Educators can use this tool to teach student nurses, new graduates and experienced staff, about the patient information to be presented at handover. RELEVANCE TO CLINICAL PRACTICE: The Nursing Handover Minimum Data Set for electronic nursing handover complements verbal handover and provides a tool to give clinicians access to comprehensive information about all patients within the ward area.
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Relações Interprofissionais , Enfermeiras e Enfermeiros , Transferência de Pacientes , Sistemas Computadorizados de Registros Médicos , Gestão da SegurançaRESUMO
AIMS AND OBJECTIVES: To report the findings of a service review--specifically the strategy to provide early childhood services 'on site' at opioid treatment clinics to address access difficulties. BACKGROUND: Child and family health nurses are skilled in the assessment and support of families during early childhood. However, women with a history of substance abuse are often cautious when engaging with universal and other health services, with the result that the infant may miss recommended developmental screening and early referral to improve health outcomes. DESIGN: In 2006, an internal review was undertaken of the integration of early childhood and parenting services at opioid treatment clinics in a large Area Health Service of New South Wales, Australia. METHODS: A qualitative study design, using semi-structured interview questions was used. Data were collected via six focus groups (4-15 participants in each group) and individual interview of child and family health nurses, nurse unit managers and clinical staff (n=58). RESULTS: Three key components of a model for providing early childhood support in collaboration with opioid treatment services were identified. First, the importance of building a trusting relationship between the woman and the child and family health nurses, second, maintaining continuity of care and a multidisciplinary/multiagency approach, and finally the importance of staff education, support and professional development. CONCLUSION: The provision of early childhood and parenting services on site, as part of a multidisciplinary 'one stop shop' approach to service delivery was a clear recommendation of the review. RELEVANCE TO CLINICAL PRACTICE: Reduction of access difficulties to specialised early childhood support is of benefit to clients, community health services attempting to provide a service to this difficult to reach population and to drug and alcohol services seeking to provide a high level of holistic care for clients.
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Analgésicos Opioides/efeitos adversos , Modelos Organizacionais , Transtornos Relacionados ao Uso de Opioides/terapia , Criança , Continuidade da Assistência ao Paciente , Feminino , Humanos , New South Wales , Desenvolvimento de PessoalRESUMO
Clinical handover is the primary source of patient information for nurses; however, inadequate information transfer compromises patient safety. We investigated the content and organization of information conveyed at 81 handovers. A structure that captures and presents the information transferred at handover emerged: identification of the patient and clinical risks, clinical history/presentation, clinical status, care plan and outcomes/goals of care (ICCCO). This approach covers essential information while allowing for prioritization of information when required. Further research into the impact of ICCCO on patient safety is in progress.
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Sistemas Computadorizados de Registros Médicos , Cuidados de Enfermagem/organização & administração , Transferência da Responsabilidade pelo Paciente/organização & administração , Segurança do Paciente , Avaliação de Processos em Cuidados de Saúde , Humanos , New South WalesRESUMO
Patient safety is compromised if vital clinical information is not available to all members of the healthcare team. Therefore, it is important to understand the differences between patient information found in nursing documentation and information presented at clinical nursing handover. Content and textual analyses of two data sets were undertaken: one containing 67 examples of nursing documentation and the other containing 195 transcripts of clinical handover to understand the scope and construction of patient information found in each communication system. Clinical handover produced a comprehensive picture of the patient's condition and care whereas nursing documentation tended to present a series of descriptions of tasks performed by nurses. There is a need to investigate new systems of communication promoting congruence between clinical handover and nursing documentation to ensure that all patient information can be accessed by all interested parties.
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Documentação , Relações Interprofissionais , Registros de Enfermagem , Transferência da Responsabilidade pelo Paciente , Austrália , Humanos , Fala , RedaçãoRESUMO
OBJECTIVES: The aim of this study was to evaluate the use of mechanical thresholds (MT), measured with the SMALGO (Small Animal ALGOmeter), and to determine whether there was a correlation between MT and Glasgow Feline Composite Measure Pain Scale (CMPS-Feline) scores in cats undergoing ovariohysterectomy. METHODS: Client-owned cats undergoing flank ovariohysterectomy were recruited. Pain scores for the pre- and postoperative periods were obtained using the CMPS-Feline in each cat by two independent investigators (A and B). Following CMPS-Feline scoring, MT were measured with the SMALGO, in the surgical area, pre- and postoperatively, only by investigator A. Each cat served as its own control for the comparison of pre- and postoperative variables. Reliability statistics were used to assess the level of inter-observer agreement (A vs B) with respect to pre- and postoperative CMPS-Feline scores, while Spearman's correlation statistics were used to analyse the relationship between MT and CMPS-Feline scores. RESULTS: Twenty-nine cats completed the study. Preoperative MT (340 g [range 108-691]) were significantly higher than postoperatively (233 g [range 19-549]; P = 0.001). CMPS-Feline scores were not found to differ significantly between the preoperative period (2 [range 0-7] for investigator A and 3.2 ± 2.3 for investigator B) and postoperative period (2 [range 0-10] for investigator A and 3 [range 0-8] for investigator B) for either investigator. Reliability statistics revealed that the level of inter-observer agreement with respect to CMPS-Feline was fair for the preoperative assessments but poor for the postoperative evaluations. There was no correlation between MT and CMPS-Feline scores. CONCLUSIONS AND RELEVANCE: Although there was no correlation with CMPS-Feline scores performed at the same timepoint, MT increased postoperatively vs baseline. Assuming that, despite analgesia, susceptibility of the surgical area to mechanical stimulation would increase after surgery, this finding suggests that MT might be useful to assess feline surgical pain. The poor level of inter-observer agreement with respect to postoperative CMPS-Feline scores highlights the potential limitations of this scale.
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Dor Aguda , Analgesia , Doenças do Gato , Dor Aguda/veterinária , Analgesia/veterinária , Animais , Gatos , Feminino , Histerectomia/veterinária , Medição da Dor/métodos , Medição da Dor/veterinária , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/veterinária , Reprodutibilidade dos TestesRESUMO
Recently it has been shown that precise dose control and an increase in the overall acquisition speed of atomic resolution scanning transmission electron microscope (STEM) images can be achieved by acquiring only a small fraction of the pixels in the image experimentally and then reconstructing the full image using an inpainting algorithm. In this paper, we apply the same inpainting approach (a form of compressed sensing) to simulated, sub-sampled atomic resolution STEM images. We find that it is possible to significantly sub-sample the area that is simulated, the number of g-vectors contributing the image, and the number of frozen phonon configurations contributing to the final image while still producing an acceptable fit to a fully sampled simulation. Here we discuss the parameters that we use and how the resulting simulations can be quantifiably compared to the full simulations. As with any Compressed Sensing methodology, care must be taken to ensure that isolated events are not excluded from the process, but the observed increase in simulation speed provides significant opportunities for real time simulations, image classification and analytics to be performed as a supplement to experiments on a microscope to be developed in the future.