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1.
Ann Thorac Surg ; 2024 Jun 04.
Article in English | MEDLINE | ID: mdl-38864803

ABSTRACT

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries. As a first step, a global needs assessment confirmed rheumatic heart disease as the overwhelming pathology requiring cardiac surgery in these regions. Subsequently, CSIA published a request for proposals to support fledgling programs that could demonstrate the backing by their governments and health care institution. Out of 11 applicants, and following an evaluation of the sites, including site visits to the 3 finalists, Mozambique and Rwanda were selected as the first Pilot Sites. Subsequently, a mentorship and training agreement was completed between Mozambique and the University of Cape Town, a middle-income country with a comparable burden of rheumatic heart disease. The agreement entails regular video calls between the heart teams, targeted training across all aspects of cardiac surgery, as well as on-site presence of mentoring teams for complex cases with the strict observance of "assisting only." In Rwanda, Team Heart, a US and Rwanda-based non-governmental organization (NGO) that has been performing cardiac surgery in Rwanda and helping to train the cardiac surgery workforce since 2008, has agreed to continue providing mentorship for the local team and to assist in the establishment of independent cardiac surgery with all that entails. This involves intermittent virtual conferences between Rwandan and US cardiologists for surgical case selection. Five years after CSIA was founded, its "Seal of Approval" for the sustainability of endorsed programs in Mozambique and Rwanda has resulted in higher case numbers, a stronger government commitment, significant upgrades of infrastructure, the nurturing of generous consumable donations by industry and the commencement of negotiations with global donors for major grants. Extending the CSIA Seal to additional deserving programs could further align the international cardiac surgical community with the principle of local cardiac surgery capacity-building in developing countries.

2.
Article in English | MEDLINE | ID: mdl-38864805

ABSTRACT

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries. As a first step, a global needs assessment confirmed rheumatic heart disease as the overwhelming pathology requiring cardiac surgery in these regions. Subsequently, CSIA published a request for proposals to support fledgling programs that could demonstrate the backing by their governments and health care institution. Out of 11 applicants, and following an evaluation of the sites, including site visits to the 3 finalists, Mozambique and Rwanda were selected as the first Pilot Sites. Subsequently, a mentorship and training agreement was completed between Mozambique and the University of Cape Town, a middle-income country with a comparable burden of rheumatic heart disease. The agreement entails regular video calls between the heart teams, targeted training across all aspects of cardiac surgery, as well as on-site presence of mentoring teams for complex cases with the strict observance of "assisting only." In Rwanda, Team Heart, a US and Rwanda-based nongovernmental organization (NGO) that has been performing cardiac surgery in Rwanda and helping to train the cardiac surgery workforce since 2008, has agreed to continue providing mentorship for the local team and to assist in the establishment of independent cardiac surgery with all that entails. This involves intermittent virtual conferences between Rwandan and US cardiologists for surgical case selection. Five years after CSIA was founded, its "Seal of Approval" for the sustainability of endorsed programs in Mozambique and Rwanda has resulted in higher case numbers, a stronger government commitment, significant upgrades of infrastructure, the nurturing of generous consumable donations by industry and the commencement of negotiations with global donors for major grants. Extending the CSIA Seal to additional deserving programs could further align the international cardiac surgical community with the principle of local cardiac surgery capacity-building in developing countries.

3.
Eur J Cardiothorac Surg ; 65(6)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38856237

ABSTRACT

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries. As a first step, a global needs assessment confirmed rheumatic heart disease as the overwhelming pathology requiring cardiac surgery in these regions. Subsequently, CSIA published a request for proposals to support fledgling programmes that could demonstrate the backing by their governments and health care institution. Out of 11 applicants, and following an evaluation of the sites, including site visits to the 3 finalists, Mozambique and Rwanda were selected as the first Pilot Sites. Subsequently, a mentorship and training agreement was completed between Mozambique and the University of Cape Town, a middle-income country with a comparable burden of rheumatic heart disease. The agreement entails regular video calls between the heart teams, targeted training across all aspects of cardiac surgery, as well as on-site presence of mentoring teams for complex cases with the strict observance of 'assisting only'. In Rwanda, Team Heart, a US and Rwanda-based non-governmental organization (NGO) that has been performing cardiac surgery in Rwanda and helping to train the cardiac surgery workforce since 2008, has agreed to continue providing mentorship for the local team and to assist in the establishment of independent cardiac surgery with all that entails. This involves intermittent virtual conferences between Rwandan and US cardiologists for surgical case selection. Five years after CSIA was founded, its 'Seal of Approval' for the sustainability of endorsed programmes in Mozambique and Rwanda has resulted in higher case numbers, a stronger government commitment, significant upgrades of infrastructure, the nurturing of generous consumable donations by industry and the commencement of negotiations with global donors for major grants. Extending the CSIA Seal to additional deserving programmes could further align the international cardiac surgical community with the principle of local cardiac surgery capacity-building in developing countries.


Subject(s)
Cardiac Surgical Procedures , Societies, Medical , Thoracic Surgery , Humans , Societies, Medical/organization & administration , Thoracic Surgery/organization & administration , Developing Countries , Global Health
4.
Asian Cardiovasc Thorac Ann ; : 2184923241259191, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38872357

ABSTRACT

Informed by the almost unimaginable unmet need for cardiac surgery in the developing regions of the world, leading surgeons, cardiologists, editors in chief of the major cardiothoracic journals as well as representatives of medical industry and government convened in December 2017 to address this unacceptable disparity in access to care. The ensuing "Cape Town Declaration" constituted a clarion call to cardiac surgical societies to jointly advocate the strengthening of sustainable, local cardiac surgical capacity in the developing world. The Cardiac Surgery Intersociety Alliance (CSIA) was thus created, comprising The Society of Thoracic Surgeons (STS), the American Association for Thoracic Surgery (AATS), the Asian Society for Cardiovascular and Thoracic Surgery (ASCVTS), the European Association for Cardio-Thoracic Surgery (EACTS) and the World Heart Federation (WHF). The guiding principle was advocacy for sustainable cardiac surgical capacity in low-income countries.

5.
Science ; 380(6651): 1282-1287, 2023 06 23.
Article in English | MEDLINE | ID: mdl-37347848

ABSTRACT

Biodiversity is declining globally in response to multiple human stressors, including climate forcing. Nonetheless, local diversity trends are inconsistent in some taxa, obscuring contributions of local processes to global patterns. Arctic tundra diversity, including plants, fungi, and lichens, declined during a 15-year experiment that combined warming with exclusion of large herbivores known to influence tundra vegetation composition. Tundra diversity declined regardless of experimental treatment, as background growing season temperatures rose with sea ice loss. However, diversity declined slower with large herbivores than without them. This difference was associated with an increase in effective diversity of large herbivores as formerly abundant caribou declined and muskoxen increased. Efforts that promote herbivore diversity, such as rewilding, may help mitigate impacts of warming on tundra diversity.


Subject(s)
Biodiversity , Extinction, Biological , Herbivory , Reindeer , Animals , Humans , Arctic Regions , Climate Change , Ice Cover , Plants , Reindeer/physiology , Tundra
6.
Transplant Proc ; 55(2): 384-386, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36914437

ABSTRACT

BACKGROUND: To review outcomes from a regionalized heart and lung transplant service over a 15-year period. METHODS: Data on organ procurements made by the Specialized Thoracic Adapted Recovery (STAR) team. The STAR team staff recorded data from November 2, 2004 to June 30, 2020, were reviewed. RESULTS: The STAR teams recovered thoracic organs from 1118 donors between November 2004 and June 2020. The teams recovered 978 hearts, 823 bilateral lungs, 89 right lungs and 92 left lungs, and 8 heart and lung sets. A total of 79% of hearts and 76.1% of lungs were transplanted, whereas 2.5% of hearts and 5.1% of lungs were declined; the remainder were used for research, valves, or abandoned. A total of 47 transplantation centers received at least 1 heart, and 37 centers received at least 1 lung during this period. The 24-hour graft survival among organs recovered by STAR teams was 100% for lungs and 99% for hearts. CONCLUSIONS: A specialized regional thoracic organ procurement team may improve transplantation rates.


Subject(s)
Heart Transplantation , Lung Transplantation , Tissue and Organ Procurement , Humans , Tissue Donors , Lung
7.
Radiography (Lond) ; 29 Suppl 1: S52-S58, 2023 05.
Article in English | MEDLINE | ID: mdl-36759222

ABSTRACT

INTRODUCTION: Despite abundant literature on the diagnosis of dementia, limited research has explored the lived experiences by radiography practitioners when delivering care to people living with dementia (PLWD). This study explored the perceptions and compatibility of current professional guidance by both radiography practitioners and key stakeholders involved in developing the Society and College of Radiographers clinical practice guideline document for caring for people with dementia. METHODS: This was a two-stage qualitative multi-method study. Fifteen diagnostic and two therapeutic radiography practitioners from across the UK participated with three asynchronous online discussion forums. One core member and three members from the key stakeholder group participated with individual semi-structured interviews. Data analysis included narrative and thematic analysis. RESULTS: Participants from both stages identified enablers and barriers to providing person-centred care (PCC) to PLWD. Three superordinate themes were identified linked to (1) Challenges in delivering person-centred care to people living with dementia, (2) The need for role specific education and training, and (3) Partnership working with carers. Challenges in delivering care included time and resource pressures. The lack of dementia specific education compounded these difficulties. Care partners were seen as an asset to providing care. CONCLUSION: Providing PCC to meet the individual needs of PLWD can be challenging in practice. This is often due to time and resource implications. There were also issues with the identification of PLWD prior to their attendance in the department. Carers could help to alleviate some challenges. There is a need for profession specific education and dementia awareness training to support the provision of PCC to PLWD. IMPLICATIONS FOR PRACTICE: Dementia training needs to be specifically tailored for radiography practitioners to bridge the gap between guidelines and clinical practice rather than being generalised from other disciplines.


Subject(s)
Caregivers , Dementia , Humans , Qualitative Research , Radiography , Patient Outcome Assessment
8.
Hernia ; 26(6): 1625-1633, 2022 12.
Article in English | MEDLINE | ID: mdl-36036822

ABSTRACT

PURPOSE: Prescribing and consumption of opioids remain highly variable. Using a national hernia registry, we aimed to identify patient and surgery specific factors associated with low and high opioid tablet consumption after inguinal hernia repair. METHODS: This was a retrospective cross-sectional study evaluating patients undergoing elective inguinal hernia repair with 30-day follow-up and patient-reported opioid consumption from March 2019 to March 2021 using the Abdominal Core Health Quality Collaborative. Clinically significant patient demographics, comorbidities, operative details, quality-of-life measurements, and surgeon prescribing data were entered into a multivariable logistic regression model to identify statistically significant predictors of patients who took no opioid tablets or >10 tablets. RESULTS: A total of 1937 patients were analyzed. Operations included 59% laparoscopic or robotic, 35% open mesh, and 6% open non-mesh repairs. Of these patients, 50% reported taking zero, 42% took 1-10, and 8% took ≥10 opioid tablets at 30-day follow-up. Patients who were older (OR 1.55, 95% CI 1.34-1.79, p-value <0.001), ASA ≤ 2 (OR 1.56, 95% CI 1.2-2.01, p-value <0.001), had no preoperative opioid use at baseline (OR 2.29, 95% CI 1.31-4.03, p-value = 0.004), had local anesthetic with general anesthesia (OR 1.39, 95% CI 1.0.5-1.85, p-value = 0.022), or prescribed <7 opioid tablets (OR 2.27, 95% CI 1.96-2.62, p-value <0.001) were more likely to take no opioid tablets. CONCLUSION: Older, healthier, opioid naïve patients with local anesthetic administered during elective inguinal hernia repair are most likely to not require opioids. Surgeon prescribing-arguably the most modifiable factor-independently correlates with both low and high opioid consumption.


Subject(s)
Hernia, Inguinal , Laparoscopy , Humans , Hernia, Inguinal/surgery , Analgesics, Opioid/therapeutic use , Herniorrhaphy/adverse effects , Retrospective Studies , Anesthetics, Local , Cross-Sectional Studies , Tablets , Surgical Mesh
9.
Hernia ; 26(3): 865-871, 2022 06.
Article in English | MEDLINE | ID: mdl-35399142

ABSTRACT

PURPOSE: Physical therapy (PT) and rehabilitation are widely utilized in a variety of disease processes to improve function, return to activities of daily living (ADLs), and promote overall recovery. However, hernia repair has struggled to adopt this practice despite operations occurring in one of the most dynamic parts of the body - the abdominal core. This study sought to understand perspectives and perceived barriers regarding the incorporation of PT and rehabilitation in hernia care. METHODS: A standardized rehabilitation protocol was developed by the Abdominal Core Health Quality Collaborative (ACHQC), a national quality improvement initiative specific to hernia disease, and launched in 2019. Empiric data from the ACHQC was then obtained to describe preliminary utilization. A prospective electronic survey was then deployed to all surgeons participating in the ACHQC to aid in interpreting the identified trends. The survey included questions regarding the current use of PT in their practice, as well as further opinions on the functionality, benefit, and barriers to its use. RESULTS: We identified 1,544 patients who were listed as receiving some form of postoperative rehabilitation, of which 992 (64.2%) had a primary diagnosis of ventral hernia and 552 (35.8%) had an inguinal hernia. Among patients who had a ventral hernia, 863 (87.0%) received self-directed rehabilitation exercises compared to 488 (88.4%) of inguinal hernia patients. The subsequent survey exploring these trends was completed by 46 ACHQC surgeons (10.2%). More than half (52%) reported using PT for hernia patients, primarily in abdominal wall reconstruction cases (92%). Of those who did not report using PT, 50% cited unknown clinical benefit and another 27% cited unknown PT resources. PT utilization was typically concentrated to the postoperative period (58%), while 42% reported also using it preoperatively. Despite 72% of respondents citing a perceived benefit of PT in hernia patients, overall use of PT was primarily reported as 'occasional' by 42%, with another 27% reporting 'rarely.' Perceived benefits of PT included increased core strength, stability, mobility, patient satisfaction, education, independence, earlier return to work and ADLs, overall improved recovery, and decreased risk of postoperative issues. Reported barriers to implementing PT in practice or adapting the ACHQC Rehabilitation Protocol included lack of education, lack of evidence of clinical benefit, and difficulties operationalizing the protocol. CONCLUSION: A national survey of hernia surgeons demonstrated willingness to adopt PT and rehabilitation protocols in their clinical practices and noted a high perceived benefit to patients. However, lack of education and evidence regarding the protocol may represent important barriers to overcome in widely disseminating these resources to patients. These gaps can be addressed through dedicated educational venues and additional studies establishing PT and rehabilitation as critical future adjuncts for the recovery of hernia repair patients.


Subject(s)
Hernia, Inguinal , Hernia, Ventral , Activities of Daily Living , Hernia, Inguinal/surgery , Hernia, Ventral/surgery , Herniorrhaphy/methods , Humans , Physical Therapy Modalities , Preliminary Data , Prospective Studies , Standard of Care
10.
Hernia ; 26(3): 855-864, 2022 06.
Article in English | MEDLINE | ID: mdl-35039950

ABSTRACT

PURPOSE: Post-operative opioid prescriptions contribute to prolonged opioid misuse and abuse. Using a national hernia registry, we aimed to evaluate the effectiveness of a data-driven educational intervention on surgeon prescribing behavior. METHODS: After collecting opioid prescribing and patient consumption data from March 2019-December 2019 in inguinal and umbilical hernia repair, the Abdominal Core Health Quality Collaborative (ACHQC) Opioid Reduction Task Force presented data at a Quality Improvement (QI) Summit to educate surgeons on strategies to minimize opioid prescribing. Surgeons were asked to implement a multimodal pain management approach and were supported with educational tools created by the task force. Prescribing and consumption data after the summit, December 2019-March 2021, were then collected to assess the effectiveness of the QI effort. RESULTS: Registry participation before and after the QI summit increased from 52 to 91 surgeons, with an increase of 353-830 umbilical hernia patients and 976-2447 inguinal hernia patients. After the summit, high (> 10 tablets) surgeon prescribers shifted toward low (≤ 10 tablets) prescribing. Yet, patients consumed less than what was prescribed, with a significant increase in patients consuming ≤ 10 tablets before and after the summit: 79-88% in umbilical hernia (p = 0.01) and 85-94% in inguinal hernia (p < 0.001). CONCLUSIONS: Following an educational QI summit by the ACHQC Opioid Reduction Task Force, high opioid prescribing has shifted toward low. However, patients consume less than prescribed, highlighting the importance of continuing this effort to reduce opioid prescribing.


Subject(s)
Hernia, Inguinal , Hernia, Umbilical , Analgesics, Opioid/therapeutic use , Hernia, Inguinal/surgery , Hernia, Umbilical/surgery , Herniorrhaphy , Humans , Pain, Postoperative/drug therapy , Pain, Postoperative/surgery , Practice Patterns, Physicians' , Registries
11.
J Eur Acad Dermatol Venereol ; 35(2): 396-402, 2021 Feb.
Article in English | MEDLINE | ID: mdl-32564428

ABSTRACT

BACKGROUND: Nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant genetic disorder. It is commonly caused by mutations in PTCH1 and chiefly characterized by multiple basal cell carcinomas (BCCs) developing prior to the age of 30 years. In rare cases, NBCCS presents with a late onset of BCC development. OBJECTIVE: To investigate BCC tumorigenesis in two brothers, who showed characteristic features of NBCCS but developed their first BCCs only after the age of 40 years. Two other siblings did not show signs of NBCCS. RESULTS: We obtained blood samples from four siblings and nine BCCs from the two brothers with NBCCS. Whole exome sequencing and RNA sequencing revealed loss of heterozygosity (LOH) of PTCH1 in eight out of nine tumours that consistently involved the same haplotype on chromosome 9. This haplotype contained a germinal splice site mutation in PTCH1 (NM_001083605:exon9:c.763-6C>A). Analysis of germline DNA confirmed segregation of this mutation with the disease. All BCCs harboured additional somatic loss-of-function (LoF) mutations in the remaining PTCH1 allele which are not typically seen in other cases of NBCCS. This suggests a hypomorphic nature of the germinal PTCH1 mutation in this family. Furthermore, all BCCs had a similar tumour mutational burden compared to BCCs of unrelated NBCCS patients while harbouring a higher number of damaging PTCH1 mutations. CONCLUSIONS: Our data suggest that a sequence of three genetic hits leads to the late development of BCCs in two brothers with NBCCS: a hypomorphic germline mutation, followed by somatic LOH and additional mutations that complete PTCH1 inactivation. These genetic events are in line with the late occurrence of the first BCC and with the higher number of damaging PTCH1 mutations compared to usual cases of NBCCS.


Subject(s)
Basal Cell Nevus Syndrome , Carcinoma, Basal Cell , Skin Neoplasms , Adult , Basal Cell Nevus Syndrome/genetics , Carcinoma, Basal Cell/genetics , Genomics , Humans , Male , Patched Receptors , Patched-1 Receptor/genetics , Siblings , Skin Neoplasms/genetics
12.
Radiography (Lond) ; 27(2): 539-545, 2021 05.
Article in English | MEDLINE | ID: mdl-33262051

ABSTRACT

INTRODUCTION: As part of the BSc (Hons) Diagnostic Radiography programme students learn and undertake research relevant to their development as first post radiographers (dose optimisation and image quality) within the Research-Informed Teaching experience (RiTe). Due to the COVID-19 pandemic, the delivery of RiTe to our year 2 students was moved to an online format using Microsoft Teams and Blackboard Collaborate and focused on a key area of current practice - COVID-19 and chest X-ray imaging. Within RiTe students are placed into collaborative enquiry-based learning (CEBL) groups to share tasks, but to also support and learn from one another. METHODS: An online survey was used to explore the year 2 student cohort task value and self-efficacy of this online version of RiTe. RESULTS: A 73% (32/44) response rate was achieved. Students found the online version of RiTe to be a positive learning and development experience. There was strong agreement that they not only found it relevant to their area of practice (task-value), but also strongly agreed that they understood and could master the skills taught (self-efficacy). CONCLUSION: This online version of RiTe was effectively structured to help scaffold student learning and development of research data analysis skills despite the lack of face-to-face teaching. The students also valued the topic area (COVID-19 and chest X-ray imaging). A blended learning approach with RiTe will be used next year with a combination of collaborative online teaching and physical data collection and analysis in the university-based X-ray imaging laboratory. Further evaluation and data collection will also be undertaken. IMPLICATIONS FOR PRACTICE: University-based empirical work in groups to learn about research can be replaced by an online mechanism whilst still maintaining task-value and acceptable self-efficacy.


Subject(s)
Biomedical Research/education , COVID-19/epidemiology , Education, Distance/methods , Education, Medical, Undergraduate/methods , Pandemics , Radiography , Radiology/education , Curriculum , Humans , Interdisciplinary Placement , SARS-CoV-2 , Self Efficacy , United Kingdom/epidemiology
13.
Astron Astrophys ; 6392020 Jul.
Article in English | MEDLINE | ID: mdl-33173232

ABSTRACT

CONTEXT: The Orion Molecular Cloud is the nearest massive-star forming region. Massive stars have profound effects on their environment due to their strong radiation fields and stellar winds. Stellar feedback is one of the most crucial cosmological parameters that determine the properties and evolution of the interstellar medium in galaxies. AIMS: We aim to understand the role that feedback by stellar winds and radiation play in the evolution of the interstellar medium. Velocity-resolved observations of the [C II] 158µm fine-structure line allow us to study the kinematics of UV-illuminated gas. Here, we present a square-degree-sized map of [C II] emission from the Orion Nebula complex at a spatial resolution of 16″ and high spectral resolution of 0.2kms-1, covering the entire Orion Nebula (M42) plus M43 and the nebulae NGC 1973, 1975, and 1977 to the north. We compare the stellar characteristics of these three regions with the kinematics of the expanding bubbles surrounding them. METHODS: We use [C II] 158µm line observations over an area of 1.2deg2 in the Orion Nebula complex obtained by the upGREAT instrument onboard SOFIA. RESULTS: The bubble blown by the O7V star θ 1 Ori C in the Orion Nebula expands rapidly, at 13kms-1. Simple analytical models reproduce the characteristics of the hot interior gas and the neutral shell of this wind-blown bubble and give us an estimate of the expansion time of 0.2 Myr. M43 with the B0.5V star NU Ori also exhibits an expanding bubble structure, with an expansion velocity of 6kms-1. Comparison with analytical models for the pressure-driven expansion of H II regions gives an age estimate of 0.02 Myr. The bubble surrounding NGC 1973, 1975, and 1977 with the central B1V star 42 Orionis expands at 1.5kms-1, likely due to the over-pressurized ionized gas as in the case of M43. We derive an age of 0.4 Myr for this structure. CONCLUSIONS: We conclude that the bubble of the Orion Nebula is driven by the mechanical energy input by the strong stellar wind from θ 1 Ori C, while the bubbles associated with M43 and NGC 1977 are caused by the thermal expansion of the gas ionized by their central later-type massive stars.

14.
Radiography (Lond) ; 26 Suppl 2: S94-S99, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32291123

ABSTRACT

INTRODUCTION: With the introduction of digital radiography, the feedback between image quality and over-exposure has been partly lost which in some cases has led to a steady increase in dose. Over the years the introduction of exposure index (EI) has been used to resolve this phenomenon referred to as 'dose creep'. Even though EI is often vendor specific it is always a related of the radiation exposure to the detector. Due to the nature of this relationship EI can also be used as a patient dose indicator, however this is not widely investigated in literature. METHODS: A total of 420 dose-area-product (DAP) and EI measurements were taken whilst varying kVp, mAs and body habitus on two different anthropomorphic phantoms (pelvis and chest). Using linear regression, the correlation between EI and DAP were examined. Additionally, two separate region of interest (ROI) placements/per phantom where examined in order to research any effect on EI. RESULTS: When dividing the data into subsets, a strong correlation between EI and DAP was shown with all R-squared values > 0.987. Comparison between the ROI placements showed a significant difference between EIs for both placements. CONCLUSION: This research shows a clear relationship between EI and radiation dose which is dependent on a wide variety of factors such as ROI placement, body habitus. In addition, pathology and manufacturer specific EI's are likely to be of influence as well. IMPLICATIONS FOR PRACTICE: The combination of DAP and EI might be used as a patient dose indicator. However, the influencing factors as mentioned in the conclusion should be considered and examined before implementation.


Subject(s)
Radiation Dosage , Radiation Exposure , Radiographic Image Enhancement , Humans , Phantoms, Imaging , Reproducibility of Results
15.
Radiography (Lond) ; 25(4): 301-307, 2019 11.
Article in English | MEDLINE | ID: mdl-31582236

ABSTRACT

INTRODUCTION: Smart glasses can be adapted to display radiographic images to allow clinician's gaze not to be directionally fixed or predetermined by computer monitor location. This study presents an analysis of eye lens dose during interventional fluoroscopy guided procedures, comparing fixed monitor positions against the use of smart glasses. METHODS: Using a head phantom (simulating the clinician), thermoluminescent dosimeters and lead shielded glasses, the dose to the eye was measured for different head 'rotations and tilts' for: gaze directed towards the main scattering source (patient/primary beam) to represent potential gaze direction if smart glasses are used; gaze directed to a range of potential computer monitor positions. An anthropomorphic pelvis phantom was utilised to simulate the patient. Accumulated dose rates (µGy s-1) from five 10-second exposures at 75 kV 25.2 mAs were recorded. RESULTS: An average DAP reading of 758.84 cGy cm2 was measured during each 10 second exposure. Whilst wearing lead shielded glasses a 6.10 - fold reduction in dose rate to the lens is possible (p < 0.05). Influence of the direction of gaze by the clinician demonstrated a wide range of dose rate reduction from 3.13% (p = 0.16) to 143.69% (p < 0.05) when the clinician's gaze was towards the main scattering source. Increased dose rate to the clinician's eyes was received despite wearing lead shielded glasses, as the angle of gaze moved 45° and 90° from 0°. CONCLUSION: If the clinician's gaze is directed towards the main scattering source a potential exists for reducing eye lens dose compared with fixed location computer monitors. Introduction of lead lined smart glasses into interventional radiology may lead to improvements in patient care, reducing the need for the clinician to look away from the patient to observe a radiographic image.


Subject(s)
Augmented Reality , Fluoroscopy/instrumentation , Radiation Protection/instrumentation , Radiography, Interventional/instrumentation , Smart Glasses , Eye/radiation effects , Female , Fluoroscopy/adverse effects , Fluoroscopy/methods , Humans , Male , Phantoms, Imaging , Radiation Exposure/prevention & control , Radiation Exposure/statistics & numerical data , Radiography, Interventional/adverse effects , Radiography, Interventional/methods , Thermoluminescent Dosimetry
16.
Hernia ; 23(6): 1149-1154, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30923979

ABSTRACT

BACKGROUND: Blood transfusions can affect the clotting cascade, leading to a hypercoagulable state. The association of a venous thromboembolic (VTE) event and perioperative blood transfusion has been identified previously in surgical patients, but not after ventral hernia repair (VHR). The aim of this study was to evaluate the risk of VTE in VHR patients who receive a perioperative blood transfusion. METHODS: The American College of Surgeons National Surgery Quality Improvement Program was queried for open (n = 34,687) and laparoscopic (n = 11,544) VHRs that occurred from 2013 to 2015. Regression analyses were used to determine factors predictive of VTE within 30-day post-operatively, the impact of bleeding requiring blood transfusion, and the influence of surgical approach on VTE. RESULTS: Post-operative VTE occurred in 246 (0.5%) VHR patients. Among those patients, 53.0% occurred after discharge. Increased age, operative time, and comorbidities increased the risk of VTE (p < 0.05). Controlling for surgical approach, perioperative blood transfusion increased the risk of VTE 10.2-fold (p < 0.0001) in open and 12.2-fold in laparoscopic VHR (p < 0.0001). CONCLUSION: Perioperative blood transfusions are associated with an increased rate of VTE following VHR, more than 50% of which occur after discharge. This study highlights the importance of identifying quality initiatives for at risk patients, including adequate VTE screening and potential prophylaxis for those who receive perioperative blood transfusions.


Subject(s)
Blood Transfusion , Hernia, Ventral/surgery , Herniorrhaphy/adverse effects , Venous Thromboembolism/etiology , Aged , Female , Humans , Laparoscopy , Male , Middle Aged , Perioperative Period , Risk Factors , Thrombophilia/etiology
17.
Nature ; 565(7741): 618-621, 2019 01.
Article in English | MEDLINE | ID: mdl-30617315

ABSTRACT

Massive stars inject mechanical and radiative energy into the surrounding environment, which stirs it up, heats the gas, produces cloud and intercloud phases in the interstellar medium, and disrupts molecular clouds (the birth sites of new stars1,2). Stellar winds, supernova explosions and ionization by ultraviolet photons control the lifetimes of molecular clouds3-7. Theoretical studies predict that momentum injection by radiation should dominate that by stellar winds8, but this has been difficult to assess observationally. Velocity-resolved large-scale images in the fine-structure line of ionized carbon ([C II]) provide an observational diagnostic for the radiative energy input and the dynamics of the interstellar medium around massive stars. Here we report observations of a one-square-degree region (about 7 parsecs in diameter) of Orion molecular core 1-the region nearest to Earth that exhibits massive-star formation-at a resolution of 16 arcseconds (0.03 parsecs) in the [C II] line at 1.9 terahertz (158 micrometres). The results reveal that the stellar wind originating from the massive star θ1 Orionis C has swept up the surrounding material to create a 'bubble' roughly four parsecs in diameter with a 2,600-solar-mass shell, which is expanding at 13 kilometres per second. This finding demonstrates that the mechanical energy from the stellar wind is converted very efficiently into kinetic energy of the shell and causes more disruption of the Orion molecular core 1 than do photo-ionization and evaporation or future supernova explosions.

18.
S Afr Med J ; 108(9): 702-704, 2018 08 28.
Article in English | MEDLINE | ID: mdl-30182888

ABSTRACT

Twelve years after cardiologists and cardiac surgeons from all over the world issued the 'Drakensberg Declaration on the Control of Rheumatic Fever and Rheumatic Heart Disease in Africa', calling on the world community to address the prevention and treatment of rheumatic heart disease (RHD) through improving living conditions, to develop pilot programmes at selected sites for control of rheumatic fever and RHD, and to periodically review progress made and challenges that remain, RHD still accounts for a major proportion of cardiovascular diseases in children and young adults in low- and middle-income countries, where more than 80% of the world population live. Globally equal in prevalence to human immunodeficiency virus infection, RHD affects 33 million people worldwide. Prevention efforts have been important but have failed to eradicate the disease. At the present time, the only effective treatment for symptomatic RHD is open heart surgery, yet that life-saving cardiac surgery is woefully absent in many endemic regions. In this declaration, we propose a framework structure to create a co-ordinated and transparent international alliance to address this inequality.


Subject(s)
Cardiac Surgical Procedures/statistics & numerical data , Health Services Accessibility , Rheumatic Fever/complications , Rheumatic Heart Disease/surgery , Child , Global Health , Humans , Prevalence , Rheumatic Fever/epidemiology , Rheumatic Heart Disease/epidemiology , South Africa/epidemiology , Treatment Outcome , Young Adult
19.
20.
Astron Astrophys ; 6062017 Oct.
Article in English | MEDLINE | ID: mdl-28989177

ABSTRACT

CONTEXT: L1630 in the Orion B molecular cloud, which includes the iconic Horsehead Nebula, illuminated by the star system σ Ori, is an example of a photodissociation region (PDR). In PDRs, stellar radiation impinges on the surface of dense material, often a molecular cloud, thereby inducing a complex network of chemical reactions and physical processes. AIMS: Observations toward L1630 allow us to study the interplay between stellar radiation and a molecular cloud under relatively benign conditions, that is, intermediate densities and an intermediate UV radiation field. Contrary to the well-studied Orion Molecular Cloud 1 (OMC1), which hosts much harsher conditions, L1630 has little star formation. Our goal is to relate the [Cii] fine-structure line emission to the physical conditions predominant in L1630 and compare it to studies of OMC1. METHODS: The [Cii] 158 µm line emission of L1630 around the Horsehead Nebula, an area of 12' × 17', was observed using the upgraded German Receiver for Astronomy at Terahertz Frequencies (upGREAT) onboard the Stratospheric Observatory for Infrared Astronomy (SOFIA). RESULTS: Of the [Cii] emission from the mapped area 95%, 13 L⊙, originates from the molecular cloud; the adjacent Hii region contributes only 5%, that is, 1 L⊙. From comparison with other data (CO(1-0)-line emission, far-infrared (FIR) continuum studies, emission from polycyclic aromatic hydrocarbons (PAHs)), we infer a gas density of the molecular cloud of nH ∼ 3 · 103 cm-3, with surface layers, including the Horsehead Nebula, having a density of up to nH ∼ 4 · 104 cm-3. The temperature of the surface gas is T ∼ 100 K. The average [Cii] cooling efficiency within the molecular cloud is 1.3 · 10-2. The fraction of the mass of the molecular cloud within the studied area that is traced by [Cii] is only 8%. Our PDR models are able to reproduce the FIR-[Cii] correlations and also the CO(1-0)-[Cii] correlations. Finally, we compare our results on the heating efficiency of the gas with theoretical studies of photoelectric heating by PAHs, clusters of PAHs, and very small grains, and find the heating efficiency to be lower than theoretically predicted, a continuation of the trend set by other observations. CONCLUSIONS: In L1630 only a small fraction of the gas mass is traced by [Cii]. Most of the [Cii] emission in the mapped area stems from PDR surfaces. The layered edge-on structure of the molecular cloud and limitations in spatial resolution put constraints on our ability to relate different tracers to each other and to the physical conditions. From our study, we conclude that the relation between [Cii] emission and physical conditions is likely to be more complicated than often assumed. The theoretical heating efficiency is higher than the one we calculate from the observed [Cii] emission in the L1630 molecular cloud.

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