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BACKGROUND: Mental fatigue and mental recovery have gained scientific attention in relation to sporting performance, yet best practice assessment and management methods are lacking. A greater understanding of current knowledge and practices in high-performance sport are necessary. OBJECTIVE: To understand the contemporary knowledge, beliefs, monitoring processes, management strategies, perceived responsibility, sources of evidence, and challenges, when assessing the mental fatigue and mental recovery of athletes in high-performance sport. METHODS: A mixed-methods survey approach obtained information from 156 multi-disciplinary high-performance sport practitioners. Descriptive outputs were reported and potential differences between key concepts were detected using Wilcoxon-signed rank analysis. Thematic analysis interpreted open-text responses. RESULTS: Only 11.5% and 5.1% of respondents indicated they were "very" knowledgeable about mental fatigue and mental recovery, respectively. Knowledge (p < 0.001) and confidence in application (p = 0.001) were significantly greater for mental fatigue than mental recovery. Nearly all respondents perceived mental fatigue and mental recovery impacted training and competition performance, with a greater negative impact during competition (p < 0.001). A limited number of respondents reported deliberate assessment (31.1%) or management (51.2%) of mental fatigue and mental recovery. A combination of sources of evidence were used to inform practice, with common challenges to implementation including staff knowledge, athlete-buy in, time-availability, and a lack of evidence. Practitioners reported that assessing and managing mental fatigue and mental recovery was multi-disciplinary in nature. CONCLUSION: Practitioners reported that mental fatigue and mental recovery did impact performance, yet this was not reflected in the implementation of evidence-based assessment and management practices in high-performance sport.
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Esportes , Humanos , Esportes/fisiologia , Atletas , Atenção , Fadiga Mental/terapiaRESUMO
The correlative imaging workflow is a method of combining information and data across modes (e.g. SEM, X-ray CT, FIB-SEM), scales (cm to nm) and dimensions (2D-3D-4D), providing a more holistic interpretation of the research question. Often, subsurface objects of interest (e.g. inclusions, pores, cracks, defects in multilayered samples) are identified from initial exploratory nondestructive 3D tomographic imaging (e.g. X-ray CT, XRM), and those objects need to be studied using additional techniques to obtain, for example, 2D chemical or crystallographic data. Consequently, an intermediate sample preparation step needs to be completed, where a targeted amount of sample surface material is removed, exposing and revealing the object of interest. At present, there is not one singular technique for removing varied thicknesses at high resolution and on a range of scales from cm to nm. Here, we review the manual and automated options currently available for targeted sample material removal, with a focus on those methods which are readily accessible in most laboratories. We summarise the approaches for manual grinding and polishing, automated grinding and polishing, microtome/ultramicrotome, and broad-beam ion milling (BBIM), with further review of other more specialist techniques including serial block face electron microscopy (SBF-SEM), and ion milling and laser approaches such as FIB-SEM, Xe plasma FIB-SEM, and femtosecond laser/LaserFIB. We also address factors which may influence the decision on a particular technique, including the composition, shape and size of the samples, sample mounting limitations, the amount of surface material to be removed, the accuracy and/or resolution of peripheral parts, the accuracy and/or resolution of the technique/instrumentation, and other more general factors such as accessibility to instrumentation, costs, and the time taken for experimentation. It is hoped that this study will provide researchers with a range of options for removal of specific amounts of sample surface material to reach subsurface objects of interest in both correlative and non-correlative workflows.
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Técnicas Histológicas , Imageamento Tridimensional , Microscopia Eletrônica de Varredura , Fluxo de Trabalho , Imageamento Tridimensional/métodos , Técnicas Histológicas/métodos , MicrotomiaRESUMO
Ecosystem accounting is a statistical framework that aims to track the state of ecosystems and ecosystem services, with periodic updates. This framework follows the statistical standard of the System of Environmental Economic Accounting Ecosystem Accounting (SEEA EA). SEEA EA is composed of physical ecosystem extent, condition and ecosystem service supply-use accounts and monetary ecosystem service and asset accounts. This paper focuses on the potential use of the "Value Transfer" (VT) valuation method to produce the monetary ecosystem service accounts, taking advantage of experience with rigorous benefit transfer methods that have been developed and tested over many years in environmental economics. Although benefit transfer methods have been developed primarily for welfare analysis, the underlying techniques and advantages are directly applicable to monetary exchange values required for ecosystem accounting. The compilation of regular accounts is about to become a key area of work for the National Statistical Offices worldwide as well as for the EU Member States in particular, due to the anticipated amendment to regulation on European environmental economic accounts introducing ecosystem accounts. On this basis, accounting practitioners have voiced their concerns in a global consultation during SEEA EA revision, about three issues in particular: the lack of resources, the need for guidelines and the challenge of periodically updating the accounts. We argue that VT can facilitate empirical applications that assess ecosystem services in monetary terms, especially at national scales and in situations with limited expertise and resources available. VT is a low-cost valuation approach in line with SEEA EA requirements able to provide periodic, rigorous and consistent estimates for use in accounts. While some methodological challenges remain, it is likely that VT can help to implement SEEA EA at scale and in time to respond to the pressing need to incorporate nature into mainstream decision-making processes.
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Conservação dos Recursos Naturais , Ecossistema , Conservação dos Recursos Naturais/métodosRESUMO
The Age of Acquisition (AoA) effect results in early-acquired words being processed more quickly and accurately than later-acquired words. This effect is argued to result from a gradual development of semantic representations and a changing neural network throughout development (Chang, Y.-N., Monaghan, P., & Welbourne, S., 2019). Some forms of the Recognition Without Identification (RWI) effects have been observed at a perceptual level. The present study used the RWI paradigm to examine whether the AoA effect is located at the perceptual loci. A total of 174 participants were presented a list of pictures (Experiment 1) or words (Experiment 2) followed by a list of mixed early- and late-acquired picture or word fragments that participants had to identify; half of which corresponded to studied words and half of which to unstudied words. Irrespective of whether the item was identified, participants then rated the likelihood that the item appeared in the study phase. In both experiments, results showed that studied items were recognised more accurately than unstudied items, even when they could not be identified and late-acquired items were recognised more than early-acquired items, even when they were not identified. Finally, RWI interacted with the AoA effect only in pictorial stimuli, suggesting that the RWI and AoA effects are located at the perceptual level.
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Reconhecimento Psicológico , Semântica , HumanosRESUMO
BACKGROUND: Programmed death-ligand 1 (PD-L1) expression is the only FDA-approved biomarker for immune checkpoint inhibitors (ICIs) in patients with lung adenocarcinoma, but sensitivity is modest. Understanding the impact of molecular phenotype, clinical characteristics, and tumor features on PD-L1 expression is largely unknown and may improve prediction of response to ICI. PATIENTS AND METHODS: We evaluated patients with lung adenocarcinoma for whom PD-L1 testing and targeted next-generation sequencing (using MSK-IMPACT) was performed on the same tissue sample. Clinical and molecular features were compared across PD-L1 subgroups to examine how molecular phenotype associated with tumor PD-L1 expression. In patients treated with anti-PD-(L)1 blockade, we assessed how these interactions impacted efficacy. RESULTS: A total of 1586 patients with lung adenocarcinoma had paired PD-L1 testing and targeted next-generation sequencing. PD-L1 negativity was more common in primary compared to metastatic samples (P < 0.001). The distribution of PD-L1 expression (lymph nodes enriched for PD-L1 high; bones predominantly PD-L1 negative) and predictiveness of PD-L1 expression on ICI response varied by organ. Mutations in KRAS, TP53, and MET significantly associated with PD-L1 high expression (each P < 0.001, Q < 0.001) and EGFR and STK11 mutations associated with PD-L1 negativity (P < 0.001, Q = 0.01; P = 0.001, Q < 0.001, respectively). WNT pathway alterations also associated with PD-L1 negativity (P = 0.005). EGFR and STK11 mutants abrogated the predictive value of PD-L1 expression on ICI response. CONCLUSION: PD-L1 expression and association with ICI response vary across tissue sample sites. Specific molecular features are associated with differential expression of PD-L1 and may impact the predictive capacity of PD-L1 for response to ICIs.
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Antígeno B7-H1 , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , MutaçãoRESUMO
A 61 year old male presented to chest clinic with a lung abscess. This ruptured and resulted in an empyema that required a small bore chest drain. Pus started bypassing the drain, spilling out subcutaneously. This was probably due to the impending formation of an empyema necessitans. To stem the flow, a large bore drain was inserted. An ambulatory bag was connected to the end of that drain which enabled outpatient management through the ambulatory care unit over a ten week period. The chest drain stayed in for nine weeks. Risk stratification using the RAPID score was applied. This is a routine medical presentation with well-known and accepted investigations with routine organisms (mixed aerobic and anaerobic microbiota) and treatment with classical broad spectrum antibiotics. The striking feature of the case is that with strict supervision, patient education and motivation, ambulatory management is perfectly feasible and safe.
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Drenagem , Empiema Pleural/terapia , Assistência Ambulatorial , Antibacterianos , Tubos Torácicos , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Despite the reported achievement of the Millennium Development Goals (MDGs) with respect to drinking water, lack of access to water remains widespread worldwide. The indicator used there to measure access to water in the MDGs refers to the use of an improved water source. However, the amount of time spent in collecting water is high in countries where access to drinking water supplies located on premises is not common. 26.3% of the world's population did not have such access in 2015. Thus the need to travel to a water point, possibly queue, fill water containers, and carry them home is prevalent. The amount of time and effort used in water collection can be considerable, and household surveys increasingly provide data on collection time. This study aims to demonstrate the effect of adding a 30-minute collection time component to monitor access to drinking water. This study draws on household surveys from 17 countries to highlight the widespread burden of fetching water and its significant impact on estimates of coverage. The proportion of the population with access decreased by 13% on average for these 17 countries when collection time was added as a consideration.
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Água Potável , Abastecimento de Água , Países em Desenvolvimento , Humanos , Fatores de Tempo , Organização Mundial da SaúdeRESUMO
An in vivo study in the laboratory rat model has been carried out to monitor changes to the spermatogenic cells in the testis tubules of adult Fasciola hepatica following treatment with the artemisinins, artemether and artesunate. Rats infected with the triclabendazole (TCBZ)-resistant Sligo isolate were dosed orally with artemether at a concentration of 200 mg/kg and flukes recovered at 24, 48 and 72 h post treatment (pt). Rats infected with the TCBZ-resistant Oberon isolate were dosed orally with artesunate at a concentration of 200 mg/kg and flukes recovered 24, 48, 72 and 96 h pt. The flukes were processed for histological and transmission electron microscope (TEM) examination. Changes to the spermatogenic cells were evident at 24 h pt with artemether. The spermatogonial and spermatocyte cells contained abnormal mitochondria, there were fewer spermatids and spermatozoa in the tubules than normal, and a number of cells showed signs of apoptosis. There was a further decline in cell numbers at 48 h pt and the organization of the spermatocyte and spermatid rosettes was atypical. Sperm formation had become abnormal and those spermatozoa present possessed only a single axoneme. By 72 h pt, the testis tubules were vacuolated and filled with abnormal cells and cell debris. Only spermatogonial cells could be identified and there was widespread evidence of apoptosis in the cells. Distinct cellular changes following artesunate treatment did not become apparent until 48 h pt. The changes seen were similar to those described for artemether, but were generally less severe at matching time-periods. The fine structural changes occurring in the spermatogenic cells were compared to those observed in other cell types and fluke tissues and the overall information was collated to identify the cellular targets for artemisinin action and to establish the time-line for drug action.
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Anti-Infecciosos/administração & dosagem , Artemisininas/administração & dosagem , Fasciola hepatica/efeitos dos fármacos , Fasciolíase/tratamento farmacológico , Administração Oral , Animais , Anti-Infecciosos/farmacologia , Apoptose , Artemeter , Artemisininas/farmacologia , Artesunato , Contagem de Células , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Fasciola hepatica/fisiologia , Histocitoquímica , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Ratos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Espermatozoides/ultraestrutura , Fatores de TempoRESUMO
OBJECTIVE: To evaluate the extent to which elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) for osteoarthritis (OA) restore normal patient-reported physical function in men and women. METHODS: Pain and physical function (WOMAC-PF) were prospectively measured pre- and post-operatively. The relationship between surgical procedure and achieving physical function equivalent to age and sex-matched adults with no hip or knee joint problems was modeled using sex-specific logistic regression. Percent change in function was also compared between groups using sex-specific generalized linear models adjusted for age, BMI, pain, comorbid conditions, time from surgery, and subsequent surgery. RESULTS: Individuals with pre- and post-operative WOMAC data were classified exclusively into either THA (287M:306F) or TKA (239M:424F) groups. The median follow-up was 476 (THA) and 474 (TKA) days for men, and 495 (THA) and 526 (TKA) days for women. MAIN OUTCOME: women with THA compared with TKA were more likely to achieve a normal level of postoperative PF while there were no significant differences between procedures in men. Additional analyses: we found slightly lower preoperative PF in THA compared with TKA. This difference resolved postoperatively in men, but women who underwent THA reported greater improvement and better PF than those who had TKA. CONCLUSION: In women, THA results in greater improvement in WOMAC-PF at approximately 1-year follow-up and better approximates physical function of community-dwelling older adults without OA than TKA does. In contrast, in men, a lack of between-group post-operative WOMAC-PF differences suggests that procedures result in a similar degree of improvement.
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Artroplastia do Joelho , Artroplastia de Quadril , Feminino , Humanos , Articulação do Joelho , Masculino , Osteoartrite , DorRESUMO
The Birmingham cluster genetic algorithm is a package that performs global optimisations for homo- and bimetallic clusters based on either first principles methods or empirical potentials. Here, we present a new parallel implementation of the code which employs a pool strategy in order to eliminate sequential steps and significantly improve performance. The new approach meets all requirements of an evolutionary algorithm and contains the main features of the previous implementation. The performance of the pool genetic algorithm is tested using the Gupta potential for the global optimisation of the Au10Pd10 cluster, which demonstrates the high efficiency of the method. The new implementation is also used for the global optimisation of the Au10 and Au20 clusters directly at the density functional theory level.
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Vibrational spectra of Au(n)Ag(m)(+)â Ar(k) (n + m = 4, 5; k = 1-4) clusters are determined by far-infrared resonant multiple photon dissociation spectroscopy in the range νÌ=100-250 cm(-1). The experimental spectra are assigned using density functional theory for geometries obtained by the Birmingham cluster genetic algorithm. Putative global minimum candidates of the Ar complexes are generated by adding Ar atoms to the Au(n)Ag(m)(+) low energy isomers and subsequent local optimization. Differential Ar binding energies indicate exceptionally strong Au-Ar bonds in Au-rich clusters, leading to fundamental changes to the IR spectra. The stronger Ar binding is attributed to a relativistically enhanced covalent character of the Au-Ar bond, while in Au-rich species charge-induced dipole interactions overcompensate the relativistic affinity to Au. Moreover, not only the absolute composition but also the topologies are essential in the description of Ar binding to a certain cluster.
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An in vivo study in the laboratory rat model has been carried out to monitor changes to the tegument and gut of adult Fasciola hepatica following treatment with artesunate. Rats infected with the triclabendazole-resistant Oberon isolate were dosed orally with artesunate at a concentration of 200 mg/kg and flukes recovered 24, 48, 72 and 96 h post-treatment (pt). The flukes were processed for scanning and transmission electron microscope examination. Changes to the external surface were limited to swelling and blebbing of the interspinal tegument. There was one exception, a specimen recovered 72 h pt, which had completely lost the syncytium over the posterior region of the fluke. Internal changes to the tegumental syncytium and cell bodies were more severe and were apparent from 48 h pt onwards. Increased numbers of secretory bodies were present in the apical region of the syncytium, the basal infolds were swollen and sloughing of the apical plasma membrane was seen at 96 h pt. In the cell bodies, there was swelling and vesiculation of the cisternae of the granular endoplasmic reticulum (ger), swelling of the mitochondria and a decrease in secretory body production. Changes to the gastrodermal cells were evident from 24 h onwards. They comprised swelling and vesiculation of the ger cisternae, swelling and lysis of the mitochondria and accumulation of autophagic vacuoles and lipid droplets. The nuclei of the cells were karyopyknotic by 96 h pt. The gut was consistently more severely affected than the tegument at all time points pt, pointing to an oral route of uptake for artesunate. This study has provided information on the primary subcellular targets for drug action in the fluke.
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Antiplatelmínticos/farmacologia , Artemisininas/farmacologia , Fasciola hepatica/efeitos dos fármacos , Administração Oral , Animais , Antiplatelmínticos/administração & dosagem , Antiplatelmínticos/uso terapêutico , Artemisininas/administração & dosagem , Artemisininas/uso terapêutico , Artesunato , Fasciola hepatica/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Ratos , Ratos Sprague-Dawley , Fatores de TempoRESUMO
An unambiguous determination of the three-dimensional structure of nanoparticles is challenging. Electron tomography requires a series of images taken for many different specimen orientations. This approach is ideal for stable and stationary structures. But ultrasmall nanoparticles are intrinsically structurally unstable and may interact with the incident electron beam, constraining the electron beam density that can be used and the duration of the observation. Here we use aberration-corrected scanning transmission electron microscopy, coupled with simple imaging simulation, to determine with atomic resolution the size, three-dimensional shape, orientation and atomic arrangement of size-selected gold nanoclusters that are preformed in the gas phase and soft-landed on an amorphous carbon substrate. The structures of gold nanoclusters containing 3096 atoms can be identified with either Ino-decahedral, cuboctahedral or icosahedral geometries. Comparison with theoretical modelling of the system suggests that the structures are consistent with energetic considerations. The discovery that nanoscale gold particles function as active and selective catalysts for a variety of important chemical reactions has provoked much research interest in recent years. We believe that the detailed structure information we provide will help to unravel the role of these nanoclusters in size- and structure-specific catalytic reactions. We note that the technique will be of use in investigations of other supported ultrasmall metal cluster systems.
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The present study is focused on the optical properties of the Ag10⺠cluster in the photon energy range âω = 1.9-4.4 eV. Absorption spectra are recorded by longitudinal molecular beam depletion spectroscopy and compared to optical response calculations using time-dependent density functional theory. Several cluster isomers obtained by the new pool-based parallel implementation of the Birmingham Cluster Genetic Algorithm, coupled with density functional theory, are used in excited state calculations. The experimental observations, together with additional simulations of ion mobilities for the several geometries found within this work using different models, clearly identify the ground state isomer of Ag10⺠to be composed of two orthogonal interpenetrating pentagonal bipyramids, having overall D(2d) symmetry.
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Combining molecular beam electric deflection experiments and global optimization techniques has proven to be a powerful tool for resolving equilibrium structures of neutral metal and semiconductor clusters. Herein, we present electric molecular beam deflection experiments on PbN (N = 7-18) clusters. Promising structures are generated using the unbiased Birmingham Cluster Genetic Algorithm approach based on density functional theory. The structures are further relaxed within the framework of two-component density functional theory taking scalar relativistic and spin orbit effects into account. Quantum chemical results are used to model electric molecular beam deflection profiles based on molecular dynamics calculations. Comparison of measured and simulated beam profiles allows the assignment of equilibrium structures for the most cluster sizes in the examined range for the first time. Neutral lead clusters adopt mainly spherical geometries and resemble the structures of lead cluster cations apart from Pb10. Their growth pattern deviates strongly from the one observed for tin and germanium clusters.
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We present experimental and theoretical studies of the optical response of mixed Ag(n)Au(+)(4-n) (n=1-3) clusters in the photon energy range âω = 1.9-3.5 eV. Absorption spectra are recorded by a newly built longitudinal molecular beam depletion spectroscopy apparatus providing lower limits to absolute photodissociation cross sections. The experimental data are compared to optical response calculations in the framework of long-range corrected time-dependent density functional theory with initial cluster geometries obtained by the unbiased Birmingham Cluster Genetic Algorithm coupled with density functional theory. Experiments and excited state calculations shed light on the structural and electronic properties of the mixed Ag-Au tetramer cations.
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Unrecognized vasa previa carries a significant risk of fetal mortality. Advances in ultrasound have improved detection of vasa previa and led to a dramatic reduction in fetal morbidity and mortality. However, current management strategies require prolonged hospitalized surveillance, preterm delivery prior to the onset of labor or rupture of membranes, and a cesarean delivery. Fetoscopic laser ablation of type II vasa previa allows for the possibility of term vaginal delivery. We present a patient who underwent successful laser photocoagulation of a type II vasa previa at 32(5)/7 weeks' gestation. She subsequently delivered vaginally at term without complications. The potential benefits of definitive in utero treatment of non-type I vasa previa, such as vaginal delivery at term, must be weighed against the procedure-related risks of operative fetoscopy.
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Nascimento a Termo , Vasa Previa/cirurgia , Adulto , Parto Obstétrico , Feminino , Fetoscopia , Humanos , Gravidez , Resultado do TratamentoRESUMO
Plexiform fibrohistiocytic tumors are rare, small, ill-defined, solitary masses found in the deep dermis or subcutaneous tissues. These tumors will ordinarily be slow-growing masses that almost solely occur in children and young adults. They have had a greater prevalence in the upper extremity than in the lower extremity, with limited reports of this lesion in the lower extremity. We report a small painful mass found in the central plantar heel of a 12-year-old male.
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Histiocitoma Fibroso Maligno/patologia , Histiocitoma Fibroso Maligno/cirurgia , Criança , Calcanhar , Humanos , Masculino , Estadiamento de Neoplasias , ReoperaçãoRESUMO
UNLABELLED: The frequency and significance of calcification in intraductal papillary mucinous neoplasms (IPMN) are unknown. We examined calcifications by computed tomography (CT) in a large cohort of IPMNs and correlated them with clinicopathologic characteristics. METHODS: Preoperative contrast-enhanced CT imaging studies of 164 patients with surgically resected IPMN were retrospectively reviewed. Morphologic characteristics of IPMN, presence and type of calcifications, their location, the degree of dysplasia and the epithelial subtype were recorded. Symptoms at the time of diagnosis, history of smoking, and alcohol consumption were obtained from medical records. RESULTS: Of the 164 IPMNs, 68 were branch duct type (Br-IPMN) and 96 main duct (MD-IPMN) or combined type (CT-IPMN); 78 (48%) had a malignant component (CIS and Invasive). Calcifications were present in 33 cases (20%). By type, 16 calcifications were punctate, 11 coarse and 9 eggshell, and by location, 15 were mural, 3 septal, 2 ductal, 1 in the solid component, and 13 in multiple locations. Calcifications were seen more frequently in larger lesions (44 mm vs 32 mm p = 0.002), and when MPD dilation was noted (70% vs 45%, p = 0.023). There was no association between presence of calcification and malignancy, epithelial subtype, or other clinical data. However, malignancy was present in 9/11 IPMN with coarse calcification (p = 0.04), suggesting this may be a worrisome feature. CONCLUSION: Calcification is found in 20% of IPMNs, and is more common in larger lesions. Although its overall presence has no correlation with malignancy, coarse calcification, when combined with other morphologic features, may be a radiologic sign of malignancy.
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Carcinoma Ductal Pancreático/patologia , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Pancreáticas/patologia , Adenocarcinoma Mucinoso/diagnóstico por imagem , Adenocarcinoma Mucinoso/patologia , Idoso , Calcinose/diagnóstico por imagem , Carcinoma Ductal Pancreático/diagnóstico por imagem , Carcinoma Papilar/diagnóstico por imagem , Carcinoma Papilar/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Epiteliais e Glandulares/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
Resolving the structure of clusters in the gas phase often requires the comparison of experimental data to quantum chemical calculations. Herein, we present the variation of a straightforward approach, in which photodissociation spectra of isolated clusters are compared to optical response calculations in order to elucidate cluster structures. Our absorption spectra were measured using a newly built longitudinal beam depletion spectroscopy apparatus and recorded in the photon energy range hω = 1.9-3.5 eV. Cluster geometries were obtained using the unbiased Birmingham Cluster Genetic Algorithm coupled with density functional theory, while the optical response was calculated in the framework of time-dependent density functional theory. Experiments and excited state calculations are in excellent agreement using long-range corrected exchange correlation functionals for both ground and excited state calculations. Our methodology indicates a contribution of Y shaped Au4(+) whereas for Ag4(+) only the ground state isomer has to be considered to explain the experimental absorption spectrum. Our extended methodology shows two nearly degenerate isomers of Au4(+) probably being present in the molecular beam and therefore shows promise for the further structure determination of pure and binary transition-metal clusters.