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1.
Ulster Med J ; 92(3): 134-138, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38292498

RESUMO

Introduction: Worldwide colonic cancer is the third most common cancer with up to 30% of cases presenting with large bowel obstruction. Self-expanding metal stents (SEMS) have been used as a bridge to surgery (BTS) in the treatment of this malignant obstruction. We review the outcomes of SEMS as a BTS across two high volume colorectal units. Methodology: A retrospective analysis of patients undergoing colonic stenting as a bridge to surgery was performed; outcomes were compared to previously published figures on emergency colonic resections. Inclusion criteria were adults (>18 years of age) undergoing colonic stenting for colonic obstruction with a view to elective resection. Patients undergoing stenting for palliation of symptoms were excluded. Results: 39 patients were identified across both trusts over a ten-year period. 90 day mortality following BTS was found to be 3.6% and there was an 82.1% (32/39) technical success rate. 46.4% proceeded to an elective resection which was started laparoscopically. Permanent stoma rate was observed at 14.3% for elective surgery. Conclusion: Stenting for relief of acute malignant obstruction as a bridge to surgery is a viable option in select patients. Further research is required to determine oncological safety and rate of local recurrences.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Obstrução Intestinal , Adulto , Humanos , Estudos Retrospectivos , Stents , Obstrução Intestinal/etiologia , Obstrução Intestinal/cirurgia , Resultado do Tratamento , Neoplasias do Colo/complicações , Neoplasias do Colo/cirurgia
2.
Clin Oncol (R Coll Radiol) ; 36(2): 119-127, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042669

RESUMO

AIMS: Cardiac disease is a dose-limiting toxicity in non-small cell lung cancer radiotherapy. The dose to the heart base has been associated with poor survival in multiple institutional and clinical trial datasets using unsupervised, voxel-based analysis. Validation has not been undertaken in a cohort with individual patient delineations of the cardiac base or for the endpoint of cardiac events. The purpose of this study was to assess the association of heart base radiation dose with overall survival and the risk of cardiac events with individual heart base contours. MATERIALS AND METHODS: Patients treated between 2015 and 2020 were reviewed for baseline patient, tumour and cardiac details and both cancer and cardiac outcomes as part of the NI-HEART study. Three cardiologists verified cardiac events including atrial fibrillation, heart failure and acute coronary syndrome. Cardiac substructure delineations were completed using a validated deep learning-based autosegmentation tool and a composite cardiac base structure was generated. Cox and Fine-Gray regressions were undertaken for the risk of death and cardiac events. RESULTS: Of 478 eligible patients, most received 55 Gy/20 fractions (96%) without chemotherapy (58%), planned with intensity-modulated radiotherapy (71%). Pre-existing cardiovascular morbidity was common (78% two or more risk factors, 46% one or more established disease). The median follow-up was 21.1 months. Dichotomised at the median, a higher heart base Dmax was associated with poorer survival on Kaplan-Meier analysis (20.2 months versus 28.3 months; hazard ratio 1.40, 95% confidence interval 1.14-1.75, P = 0.0017) and statistical significance was retained in multivariate analyses. Furthermore, heart base Dmax was associated with pooled cardiac events in a multivariate analysis (hazard ratio 1.75, 95% confidence interval 1.03-2.97, P = 0.04). CONCLUSIONS: Heart base Dmax was associated with the rate of death and cardiac events after adjusting for patient, tumour and cardiovascular factors in the NI-HEART study. This validates the findings from previous unsupervised analytical approaches. The heart base could be considered as a potential sub-organ at risk towards reducing radiation cardiotoxicity.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Cardiopatias , Neoplasias Pulmonares , Radioterapia de Intensidade Modulada , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Coração , Radioterapia de Intensidade Modulada/efeitos adversos , Cardiopatias/epidemiologia , Cardiopatias/etiologia , Doses de Radiação
3.
Integr Org Biol ; 5(1): obad039, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38078056

RESUMO

Species ecology and life history patterns are often reflected in animal morphology. Blue whales are globally distributed, with distinct populations that feed in different productive coastal regions worldwide. Thus, they provide an opportunity to investigate how regional ecosystem characteristics may drive morphological differences within a species. Here, we compare physical and biological oceanography of three different blue whale foraging grounds: (1) Monterey Bay, California, USA; (2) the South Taranaki Bight (STB), Aotearoa New Zealand; and (3) the Corcovado Gulf, Chile. Additionally, we compare the morphology of blue whales from these regions using unoccupied aircraft imagery. Monterey Bay and the Corcovado Gulf are seasonally productive and support the migratory life history strategy of the Eastern North Pacific (ENP) and Chilean blue whale populations, respectively. In contrast, the New Zealand blue whale population remains in the less productive STB year-round. All three populations were indistinguishable in total body length. However, New Zealand blue whales were in significantly higher body condition despite lower regional productivity, potentially attributable to their non-migratory strategy that facilitates lower risk of spatiotemporal misalignment with more consistently available foraging opportunities. Alternatively, the migratory strategy of the ENP and Chilean populations may be successful when their presence on the foraging grounds temporally aligns with abundant prey availability. We document differences in skull and fluke morphology between populations, which may relate to different feeding behaviors adapted to region-specific prey and habitat characteristics. These morphological features may represent a trade-off between maneuverability for prey capture and efficient long-distance migration. As oceanographic patterns shift relative to long-term means under climate change, these blue whale populations may show different vulnerabilities due to differences in migratory phenology and feeding behavior between regions. Spanish abstract La ecología y patrones de historia de vida de las especies a menudo se reflejan en la morfología animal. Las ballenas azules están distribuidas globalmente, con poblaciones separadas que se alimentan en diferentes regiones costeras productivas de todo el mundo. Por lo tanto, brindan la oportunidad de investigar cómo las características regionales de los ecosistemas pueden impulsar diferencias morfológicas dentro de una especie. Aquí, comparamos la oceanografía física y biológica de tres zonas de alimentación diferentes de la ballena azul: (1) Bahía de Monterey, California, EE. UU., (2) Bahía del sur de Taranaki (BST), Nueva Zelanda, y (3) Golfo de Corcovado, Chile. Adicionalmente, comparamos la morfología de las ballenas azules de estas regiones utilizando imágenes de aeronaves no tripuladas. La Bahía de Monterey y el Golfo de Corcovado son estacionalmente productivos y apoyan la estrategia migratoria de la historia de vida de las poblaciones de ballena azul chilena y del Pacífico Norte Oriental (PNO), respectivamente. Por el contrario, la población de ballena azul de Nueva Zelanda permanece en la menos productiva BST durante todo el año. Las tres poblaciones eran indistinguibles en cuanto a la longitud corporal total. Sin embargo, las ballenas azules de Nueva Zelanda tenían una condición corporal significativamente mayor a pesar de una menor productividad regional, potencialmente atribuible a su estrategia no migratoria que facilita un menor riesgo de desalineación espaciotemporal con oportunidades de alimentación disponibles de manera más consistente. Alternativamente, la estrategia migratoria de las poblaciones de ballenas PNO y chilena puede tener éxito cuando su presencia en las zonas de alimentación se alinea temporalmente con la abundante disponibilidad de presas. Documentamos diferencias en la morfología del cráneo y la aleta caudal entre poblaciones, que pueden estar relacionadas con diferentes comportamientos de alimentación adaptados a las características de hábitat y presas específicas para cada región. Estas características morfológicas pueden representar una compensación entre la maniobrabilidad para la captura de presas y una migración eficiente a larga distancia. A medida que los patrones oceanográficos cambian en términos de mediano a largo plazo debido al cambio climático, estas poblaciones de ballenas azules pueden mostrar diferentes vulnerabilidades debido a diferencias en la fenología migratoria y el comportamiento de alimentación entre regiones.

4.
Science ; 382(6673): 946-951, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37995229

RESUMO

Reconstructions of coupled carbon, oxygen, and sulfur cycles rely heavily on sedimentary pyrite sulfur isotope compositions (δ34Spyr). With a model of sediment diagenesis, paired with global datasets of sedimentary parameters, we show that the wide range of δ34Spyr (~100 per mil) in modern marine sediments arises from geographic patterns in the relative rates of diffusion, burial, and microbial reduction of sulfate. By contrast, the microbial sulfur isotope fractionation remains large and relatively uniform. Over Earth history, the effect of increasing seawater sulfate and oxygen concentrations on sulfate and sulfide transport and reaction may explain the corresponding increase observed in the δ34S offset between sulfate and pyrite. More subtle variations may be related to changes in depositional environments associated with sea level fluctuations and supercontinent cycles.

5.
J Robot Surg ; 17(4): 1803-1808, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37079149

RESUMO

Transoral robotic surgery (TORS) in children is in its infancy, and indications have been primarily limited to lingual tonsillar hypertrophy and superficial mucosal lesions. However, the relatively avascular channel of the midline posterior tongue, vallecula, and posterior hyoid space provides a safe plane of dissection for deep lesions of the tongue and access to structures in the anterior neck. As robotic surgeons gain experience, application of this technology will continue to grow. The method is retrospective case series. We present seven patients who had either a primary (n = 3) or recurrent (n = 4) lingual thyroglossal duct cyst (TGDC) and underwent TORS excision. Four of the seven patients also underwent transoral resection of the central portion of the hyoid bone, while three had central hyoid resection during prior surgery. Two minor complications occurred with no evidence of lesion recurrence after mean follow-up of 19.7 mo. The midline avascular channel of the tongue allows for relatively bloodless surgical access to pathologies of the midline base of tongue and anterior neck. Lingual thyroglossal duct cysts can safely be removed via a TORS approach with evidence of limited recurrence. Robotic technology can provide safe and effective surgical alternatives for children with a variety of pathologies, and we aim to promote the widespread adoption of TORS in pediatric head and neck surgery by sharing our knowledge and clinical experience. Further study and publication are needed to establish safety and efficacy.


Assuntos
Procedimentos Cirúrgicos Robóticos , Robótica , Cisto Tireoglosso , Humanos , Criança , Procedimentos Cirúrgicos Robóticos/métodos , Estudos Retrospectivos , Língua/cirurgia , Língua/patologia , Osso Hioide , Cisto Tireoglosso/cirurgia , Cisto Tireoglosso/patologia
6.
Artigo em Inglês | MEDLINE | ID: mdl-36901467

RESUMO

Little is known about digital health interventions used to support treatment for pregnant and early parenting women (PEPW) with substance use disorders (SUD). METHODS: Guided by the Arksey and O'Malley's Scoping Review Framework, empirical studies were identified within the CINAHL, PsycInfo, PubMed, and ProQuest databases using subject headings and free-text keywords. Studies were selected based on a priori inclusion/exclusion criteria, and data extraction and descriptive analysis were performed. RESULTS: A total of 27 original studies and 30 articles were included. Varying study designs were used, including several feasibility and acceptability studies. However, efficacious findings on abstinence and other clinically important outcomes were reported in several studies. Most studies focused on digital interventions for pregnant women (89.7%), suggesting a dearth of research on how digital technologies may support early parenting women with SUD. No studies included PEPW family members or involved PEPW women in the intervention design. CONCLUSIONS: The science of digital interventions to support treatment for PEPW is in an early stage, but feasibility and efficacy results are promising. Future research should explore community-based participatory partnerships with PEPW to develop or tailor digital interventions and include family or external support systems to engage in the intervention alongside PEPW.


Assuntos
Tecnologia Digital , Transtornos Relacionados ao Uso de Substâncias , Humanos , Feminino , Gravidez , Poder Familiar , Transtornos Relacionados ao Uso de Substâncias/terapia , PubMed
7.
Ulster Med J ; 91(3): 139-142, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36474845

RESUMO

Straight to test (STT) is a recognised pathway for improving the waiting time for red flag referrals. Electronic patient care records (ECR) provide clinicians with a greater volume of clinical information allowing virtual triage and STT. We aimed to assess if using ECR and STT can reduce delays in diagnosis and treatment. A review of 300 colorectal referrals between 2018-2019 was performed. Patients awaiting an appointment were reviewed electronically, by a single colorectal surgeon and re-triaged STT if appropriate. The delay in time from referral to initial review was removed, creating a second group for statistical comparison to demonstrate time saved if the strategy was adopted at the point of original triage. 91.3% (n= 274) were red flag referrals. 94% (n=282) were sent STT. Patients processed via traditional referral and clinic had a median time to scope of 36 days compared with 22.5 days, p < 0.001 if triaged STT via virtual clinic. Median time to management was 59 days for traditional and 35 days for STT, p < 0.001.

8.
R Soc Open Sci ; 9(11): 220724, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36397972

RESUMO

Antarctic minke whales (Balaenoptera bonaerensis, AMW) are an abundant, ice-dependent species susceptible to rapid climatic changes occurring in parts of the Antarctic. Here, we used remote biopsy samples and estimates of length derived from unoccupied aircraft system (UAS) to characterize for the first time the sex ratio, maturity, and pregnancy rates of AMWs around the Western Antarctic Peninsula (WAP). DNA profiling of 82 biopsy samples (2013-2020) identified 29 individual males and 40 individual females. Blubber progesterone levels indicated 59% of all sampled females were pregnant, irrespective of maturity. When corrected for sexual maturity, the median pregnancy rate was 92.3%, indicating that most mature females become pregnant each year. We measured 68 individuals by UAS (mean = 8.04 m) and estimated that 66.5% of females were mature. This study provides the first data on the demography of AMWs along the WAP and represents the first use of non-lethal approaches to studying this species. Furthermore, these results provide baselines against which future changes in population status can be assessed in this rapidly changing marine ecosystem.

9.
Sci Rep ; 12(1): 20250, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36424421

RESUMO

Glucocorticoids are regularly used as biomarkers of relative health for individuals and populations. Around the Western Antarctic Peninsula (WAP), baleen whales have and continue to experience threats, including commercial harvest, prey limitations and habitat change driven by rapid warming, and increased human presence via ecotourism. Here, we measured demographic variation and differences across the foraging season in blubber cortisol levels of humpback whales (Megaptera novaeangliae) over two years around the WAP. Cortisol concentrations were determined from 305 biopsy samples of unique individuals. We found no significant difference in the cortisol concentration between male and female whales. However, we observed significant differences across demographic groups of females and a significant decrease in the population across the feeding season. We also assessed whether COVID-19-related reductions in tourism in 2021 along the WAP correlated with lower cortisol levels across the population. The decline in vessel presence in 2021 was associated with a significant decrease in humpback whale blubber cortisol concentrations at the population level. Our findings provide critical contextual data on how these hormones vary naturally in a population over time, show direct associations between cortisol levels and human presence, and will enable comparisons among species experiencing different levels of human disturbance.


Assuntos
COVID-19 , Jubarte , Humanos , Animais , Masculino , Feminino , Hidrocortisona , Regiões Antárticas , Estações do Ano
10.
Occup Med (Lond) ; 72(1): 17-24, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34693972

RESUMO

BACKGROUND: Anxiety and depression account for considerable cost to organizations, driven by both presenteeism (reduced performance due to attending work while ill) and absenteeism. Most research has focused on the impact of depression, with less attention given to anxiety and comorbid presentations. AIMS: To explore the cross-sectional relationship between depression and anxiety (individually and comorbidly) on workplace performance and sickness absence. METHODS: As part of a larger study to evaluate a mental health app, 4953 working Australians were recruited. Participants completed in-app assessment including demographic questions, the Patient Health Questionnaire-9, two-item Generalized Anxiety Disorder and questions from the World Health Organization Health and Work Performance Questionnaire. Cut-off scores were used to establish probable cases of depression alone, anxiety alone and comorbidity. RESULTS: Of the total sample, 7% met cut-off for depression only, 13% anxiety only, while 16% were comorbid. Those with comorbidity reported greater symptom severity, poorer work performance and more sickness absence compared to all other groups. Presenteeism and absenteeism were significantly worse in those with depression only and anxiety only compared to those with non-clinical symptom levels. Although those with depression alone tended to have poorer outcomes than the anxiety-only group, when sample prevalence rates were considered, the impact on presenteeism was comparable. CONCLUSIONS: Workplace functioning is heavily impacted by depression and anxiety both independently and where they co-occur. While comorbidity and more severe depression presentations stand out as impairing, workplace interventions should also prioritize targeting of anxiety disorders (and associated presenteeism) given their high population prevalence.


Assuntos
Absenteísmo , Depressão , Ansiedade/epidemiologia , Transtornos de Ansiedade/epidemiologia , Austrália/epidemiologia , Comorbidade , Depressão/epidemiologia , Depressão/psicologia , Humanos , Inquéritos e Questionários , Local de Trabalho/psicologia
11.
Science ; 374(6569): 874-879, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34762476

RESUMO

In mammals and flies, only one cell in a multicellular female germline cyst becomes an oocyte, but how symmetry is broken to select the oocyte is unknown. Here, we show that the microtubule (MT) minus end-stabilizing protein Patronin/CAMSAP marks the future Drosophila oocyte and is required for oocyte specification. The spectraplakin Shot recruits Patronin to the fusome, a branched structure extending into all cyst cells. Patronin stabilizes more MTs in the cell with the most fusome material. Our data suggest that this weak asymmetry is amplified by Dynein-dependent transport of Patronin-stabilized MTs. This forms a polarized MT network, along which Dynein transports oocyte determinants into the presumptive oocyte. Thus, Patronin amplifies a weak fusome anisotropy to break symmetry and select one cell to become the oocyte.


Assuntos
Proteínas de Drosophila/metabolismo , Células Germinativas/fisiologia , Proteínas Associadas aos Microtúbulos/metabolismo , Oócitos/fisiologia , Animais , Anisotropia , Drosophila melanogaster , Dineínas/metabolismo , Feminino , Células Germinativas/ultraestrutura , Proteínas dos Microfilamentos/metabolismo , Centro Organizador dos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Oócitos/ultraestrutura , Organelas/metabolismo , Organelas/ultraestrutura
12.
Geobiology ; 19(5): 450-459, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33989454

RESUMO

The ability of aerobic microorganisms to regulate internal and external concentrations of the reactive oxygen species (ROS) superoxide directly influences the health and viability of cells. Superoxide dismutases (SODs) are the primary regulatory enzymes that are used by microorganisms to degrade superoxide. SOD is not one, but three separate, non-homologous enzymes that perform the same function. Thus, the evolutionary history of genes encoding for different SOD enzymes is one of convergent evolution, which reflects environmental selection brought about by an oxygenated atmosphere, changes in metal availability, and opportunistic horizontal gene transfer (HGT). In this study, we examine the phylogenetic history of the protein sequence encoding for the nickel-binding metalloform of the SOD enzyme (SodN). The genomic potential to produce SodN is widespread among bacteria, including Actinobacteriota (Actinobacteria), Chloroflexota (Chloroflexi), Cyanobacteria, Proteobacteria, Patescibacteria, and others. The gene is also present in many archaea, with Thermoplasmatota and Nanoarchaeota representing the vast majority of archaeal sodN diversity. A comparison of organismal and SodN protein phylogenetic trees reveals several instances of HGT, including multiple inter-domain transfers of the sodN gene from the bacterial domain to the archaeal domain. Nearly half of the archaeal members with sodN live in the photic zone of the marine water column. The sodN gene is widespread and characterized by apparent vertical gene transfer in some sediment- or soil-associated lineages within the Actinobacteriota and Chloroflexota phyla, suggesting the ancestral sodN likely originated in one of these clades before expanding its taxonomic and biogeographic distribution to additional microbial groups in the surface ocean in response to decreasing iron availability. In addition to decreasing iron quotas, nickel-binding SOD has the added benefit of withstanding high reactant and product ROS concentrations without damaging the enzyme, making it particularly well suited for the modern surface ocean.


Assuntos
Archaea/genética , Bactérias/genética , Transferência Genética Horizontal , Níquel , Superóxido Dismutase , Sequência de Aminoácidos , Filogenia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
13.
Clin Oncol (R Coll Radiol) ; 33(8): e331-e338, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33863615

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Neoplasias Pulmonares/radioterapia , Contagem de Linfócitos , Linfócitos , Recidiva Local de Neoplasia/radioterapia , Neutrófilos , Prognóstico , Estudos Retrospectivos
14.
J Phys Condens Matter ; 33(10): 105401, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33570049

RESUMO

A Raman spectroscopy study on high quality single crystals of SrCr2 As2 (SCA) in the temperature T range 4 K < T < 300 K and high applied magnetic fields up to H = 9 T is presented. The chromium B 1g phonon analysis reveals two anomalous shifts in the frequency, the first below T = 250 K at H = 0 T in the saturated AFM G-type order likely due to an enhanced electron-phonon coupling by the magnetic order, whereas the second anomaly occurs above H = 4 T at T = 4 K likely as a consequence of a magnetostructural displacive transition. Renormalization of the electronic Raman spectra in both studies reveals a decrease in the electronic density of states with decreasing T and increasing H, respectively, with consequent changes in the Fermi surface, which are intrinsically related to the observed anomalies.

15.
Nat Commun ; 12(1): 999, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579928

RESUMO

Knowledge of magnetic symmetry is vital for exploiting nontrivial surface states of magnetic topological materials. EuIn2As2 is an excellent example, as it is predicted to have collinear antiferromagnetic order where the magnetic moment direction determines either a topological-crystalline-insulator phase supporting axion electrodynamics or a higher-order-topological-insulator phase with chiral hinge states. Here, we use neutron diffraction, symmetry analysis, and density functional theory results to demonstrate that EuIn2As2 actually exhibits low-symmetry helical antiferromagnetic order which makes it a stoichiometric magnetic topological-crystalline axion insulator protected by the combination of a 180∘ rotation and time-reversal symmetries: [Formula: see text]. Surfaces protected by [Formula: see text] are expected to have an exotic gapless Dirac cone which is unpinned to specific crystal momenta. All other surfaces have gapped Dirac cones and exhibit half-integer quantum anomalous Hall conductivity. We predict that the direction of a modest applied magnetic field of µ0H ≈ 1 to 2 T can tune between gapless and gapped surface states.

16.
Sci Rep ; 11(1): 2070, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33483596

RESUMO

The modern nitrogen cycle consists of a web of microbially mediated redox transformations. Among the most crucial reactions in this cycle is the oxidation of ammonia to nitrite, an obligately aerobic process performed by a limited number of lineages of bacteria (AOB) and archaea (AOA). As this process has an absolute requirement for O2, the timing of its evolution-especially as it relates to the Great Oxygenation Event ~ 2.3 billion years ago-remains contested and is pivotal to our understanding of nutrient cycles. To estimate the antiquity of bacterial ammonia oxidation, we performed phylogenetic and molecular clock analyses of AOB. Surprisingly, bacterial ammonia oxidation appears quite young, with crown group clades having originated during Neoproterozoic time (or later) with major radiations occurring during Paleozoic time. These results place the evolution of AOB broadly coincident with the pervasive oxygenation of the deep ocean. The late evolution AOB challenges earlier interpretations of the ancient nitrogen isotope record, predicts a more substantial role for AOA during Precambrian time, and may have implications for understanding of the size and structure of the biogeochemical nitrogen cycle through geologic time.


Assuntos
Compostos de Amônio/metabolismo , Bactérias/metabolismo , Oxirredução , Filogenia
17.
Anaesthesia ; 76 Suppl 1: 40-52, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33426663

RESUMO

Utilisation of regional anaesthesia is increasing globally; however, it remains challenging to determine the overall benefit of individual regional anaesthesia procedures. Like any peri-operative intervention, the benefit to the patient and healthcare system must outweigh any patient risk or resource implications. This review aims to identify markers of success in regional anaesthesia, categorise these into an objective framework and rationalise suggestions on how measuring outcomes in regional anaesthesia can be used to develop the widespread performance of this evolving subspecialty. This framework of measuring success of regional anaesthesia contains four pillars: patient-centred, population-centred, healthcare-centred and training-centred outcomes. Each pillar of success contains several outcomes which provide a structure for the measurement and development of regional anaesthesia success on a global scale.


Assuntos
Anestesia por Condução/normas , Anestesia por Condução/efeitos adversos , Humanos , Medição de Risco , Resultado do Tratamento
18.
Clin Oncol (R Coll Radiol) ; 33(3): 145-154, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32978027

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/radioterapia , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologia
19.
J Phys Condens Matter ; 33(11): 115802, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33377475

RESUMO

The ternary-arsenide compound BaCo2As2 was previously proposed to be in proximity to a quantum-critical point where long-range ferromagnetic (FM) order is suppressed by quantum fluctuations. Here we report the effect of Ir substitutions for Co on the magnetic and thermal properties of Ba[Formula: see text] (0 ⩽ x ⩽ 0.25) single crystals. These compositions all crystallize in an uncollapsed body-centered-tetragonal ThCr2Si2 structure with space group I4/mmm. Magnetic susceptibility measurements reveal clear signatures of short-range FM ordering for x ⩾ 0.11 below a nearly composition-independent characteristic temperature T cl ≈ 13 K. The small variation of T cl with x, thermomagnetic irreversibility between zero-field-cooled and field-cooled magnetic susceptibility versus T, the occurrence of hysteresis in magnetization versus field isotherms at low field and temperature, and very small spontaneous and remanent magnetizations <0.01 µ B/f.u. together indicate that the FM response arises from short-range FM ordering of FM spin clusters as previously inferred to occur in Ca(Co1-x Ir x )2-y As2. Heat-capacity C p(T) data do not exhibit any clear feature around T cl, consistent with the very small moments of the FM clusters. The C p(T) in the paramagnetic temperature regime 25-300 K is well described by the sum of a Sommerfeld electronic contribution and Debye and Einstein lattice contributions where the latter lattice contribution suggests the presence of low-frequency optic modes associated with the heavy Ba atoms in the crystals.

20.
J Exp Biol ; 223(Pt 20)2020 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-32820028

RESUMO

Fundamental scaling relationships influence the physiology of vital rates, which in turn shape the ecology and evolution of organisms. For diving mammals, benefits conferred by large body size include reduced transport costs and enhanced breath-holding capacity, thereby increasing overall foraging efficiency. Rorqual whales feed by engulfing a large mass of prey-laden water at high speed and filtering it through baleen plates. However, as engulfment capacity increases with body length (engulfment volume∝body length3.57), the surface area of the baleen filter does not increase proportionally (baleen area∝body length1.82), and thus the filtration time of larger rorquals predictably increases as the baleen surface area must filter a disproportionally large amount of water. We predicted that filtration time should scale with body length to the power of 1.75 (filter time∝body length1.75). We tested this hypothesis on four rorqual species using multi-sensor tags with corresponding unoccupied aircraft systems-based body length estimates. We found that filter time scales with body length to the power of 1.79 (95% CI: 1.61-1.97). This result highlights a scale-dependent trade-off between engulfment capacity and baleen area that creates a biomechanical constraint to foraging through increased filtration time. Consequently, larger whales must target high-density prey patches commensurate to the gulp size to meet their increased energetic demands. If these optimal patches are absent, larger rorquals may experience reduced foraging efficiency compared with smaller whales if they do not match their engulfment capacity to the size of targeted prey aggregations.


Assuntos
Metabolismo Energético , Comportamento Alimentar , Animais , Fenômenos Biomecânicos , Tamanho Corporal , Baleias
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