RESUMO
Spinel-structured solids were studied to understand if fast Li+ ion conduction can be achieved with Li occupying multiple crystallographic sites of the structure to form a "Li-stuffed" spinel, and if the concept is applicable to prepare a high mixed electronic-ionic conductive, electrochemically active solid solution of the Li+ stuffed spinel with spinel-structured Li-ion battery electrodes. This could enable a single-phase fully solid electrode eliminating multi-phase interface incompatibility and impedance commonly observed in multi-phase solid electrolyte-cathode composites. Materials of composition Li1.25M(III)0.25TiO4, M(III) = Cr or Al were prepared through solid-state methods. The room-temperature bulk Li+-ion conductivity is 1.63 × 10-4 S cm-1 for the composition Li1.25Cr0.25Ti1.5O4. Addition of Li3BO3 (LBO) increases ionic and electronic conductivity reaching a bulk Li+ ion conductivity averaging 6.8 × 10-4 S cm-1, a total Li-ion conductivity averaging 4.2 × 10-4 S cm-1, and electronic conductivity averaging 3.8 × 10-4 S cm-1 for the composition Li1.25Cr0.25Ti1.5O4 with 1 wt. % LBO. An electrochemically active solid solution of Li1.25Cr0.25Mn1.5O4 and LiNi0.5Mn1.5O4 was prepared. This work proves that Li-stuffed spinels can achieve fast Li-ion conduction and that the concept is potentially useful to enable a single-phase fully solid electrode without interphase impedance.
RESUMO
PURPOSE: The aim of this study was to assess how often women with undetected calcifications in prior screening mammograms are subsequently diagnosed with invasive cancer. METHODS: From a screening cohort of 63,895 women, exams were collected from 59,690 women without any abnormalities, 744 women with a screen-detected cancer and a prior negative exam, 781 women with a false positive exam based on calcifications, and 413 women with an interval cancer. A radiologist identified cancer-related calcifications, selected by a computer-aided detection system, on mammograms taken prior to screen-detected or interval cancer diagnoses. Using this ground truth and the pathology reports, the sensitivity for calcification detection and the proportion of lesions with visible calcifications that developed into invasive cancer were determined. RESULTS: The screening sensitivity for calcifications was 45.5%, at a specificity of 99.5%. A total of 68.4% (n = 177) of cancer-related calcifications that could have been detected earlier were associated with invasive cancer when diagnosed. CONCLUSIONS: Screening sensitivity for detection of malignant calcifications is low. Improving the detection of these early signs of cancer is important, because the majority of lesions with detectable calcifications that are not recalled immediately but detected as interval cancer or in the next screening round are invasive at the time of diagnosis.
Assuntos
Neoplasias da Mama/complicações , Calcinose/diagnóstico , Diagnóstico Precoce , Adulto , Idoso , Neoplasias da Mama/patologia , Calcinose/complicações , Calcinose/patologia , Feminino , Humanos , Mamografia , Programas de Rastreamento , Pessoa de Meia-IdadeRESUMO
People seeking abortion may need or want emotional or informational support before, during, and after their abortion. Feeling supported and affirmed contributes to perceptions of quality care. The All-Options Talkline offers free, telephone-based, peer counselling to callers anywhere in the United States. This study aimed to explore the types of support received through the Talkline and the ways it supplemented other forms of support received by people who obtained an abortion. Between May 2021 and February 2022, we conducted 30 interviews via telephone or Zoom with callers recruited through the Talkline. We coded the interviews and conducted thematic analysis, focusing on themes related to gaps of support from family, friends, and healthcare professionals, as well as types of support received through the Talkline. We identified four key motivations for calling the Talkline, including the need for (1) decision-making support and validation, (2) a neutral perspective, (3) emotional support to discuss negative or complex feelings, and (4) information about the abortion process. Participants indicated that interactions with family, friends, and healthcare professionals ranged from unsupportive and negative, to substantially supportive. Access to the Talkline was particularly useful prior to clinical interactions and in the weeks or months after an abortion. We found that the All-Options Talkline provided person-centred, remote support for callers, filling gaps or supplementing support from one's community or healthcare professionals. Abortion support from non-medically trained support people contributes to high-quality abortion care, especially in a time of increasing abortion restrictions and use of remote abortion services.
Assuntos
Aborto Induzido , Feminino , Gravidez , Humanos , Emoções , Pessoal de Saúde , Motivação , Qualidade da Assistência à SaúdeRESUMO
Elucidating the neural pathways that underlie brain function is one of the greatest challenges in neuroscience. Light sheet based microscopy is a cutting edge method to map cerebral circuitry through optical sectioning of cleared mouse brains. However, the image contrast provided by this method is not sufficient to resolve and reconstruct the entire neuronal network. Here we combined the advantages of light sheet illumination and confocal slit detection to increase the image contrast in real time, with a frame rate of 10 Hz. In fact, in confocal light sheet microscopy (CLSM), the out-of-focus and scattered light is filtered out before detection, without multiple acquisitions or any post-processing of the acquired data. The background rejection capabilities of CLSM were validated in cleared mouse brains by comparison with a structured illumination approach. We show that CLSM allows reconstructing macroscopic brain volumes with sub-cellular resolution. We obtained a comprehensive map of Purkinje cells in the cerebellum of L7-GFP transgenic mice. Further, we were able to trace neuronal projections across brain of thy1-GFP-M transgenic mice. The whole-brain high-resolution fluorescence imaging assured by CLSM may represent a powerful tool to navigate the brain through neuronal pathways. Although this work is focused on brain imaging, the macro-scale high-resolution tomographies affordable with CLSM are ideally suited to explore, at micron-scale resolution, the anatomy of different specimens like murine organs, embryos or flies.
Assuntos
Encéfalo/anatomia & histologia , Aumento da Imagem/instrumentação , Iluminação/instrumentação , Microscopia Confocal/instrumentação , Microscopia Confocal/veterinária , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Camundongos , Camundongos Transgênicos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
In this paper, we propose a novel method for the detection of small lesions in digital medical images. Our approach is based on a multi-context ensemble of convolutional neural networks (CNNs), aiming at learning different levels of image spatial context and improving detection performance. The main innovation behind the proposed method is the use of multiple-depth CNNs, individually trained on image patches of different dimensions and then combined together. In this way, the final ensemble is able to find and locate abnormalities on the images by exploiting both the local features and the surrounding context of a lesion. Experiments were focused on two well-known medical detection problems that have been recently faced with CNNs: microcalcification detection on full-field digital mammograms and microaneurysm detection on ocular fundus images. To this end, we used two publicly available datasets, INbreast and E-ophtha. Statistically significantly better detection performance were obtained by the proposed ensemble with respect to other approaches in the literature, demonstrating its effectiveness in the detection of small abnormalities.
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Fundo de Olho , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Aprendizado Profundo , Humanos , Mamografia/métodosRESUMO
PURPOSE OF REVIEW: This paper will review recent use of syndemic frameworks in HIV research among African-Americans. RECENT FINDINGS: Researchers have used syndemic theory in diverse African-American study populations, including MSM, cis-women, trans-women, heterosexual men and adolescents. These studies have evaluated the associations between syndemic conditions and a variety of outcomes, such as sexual behaviours, HIV and other sexually transmitted infections, HIV testing, adherence to antiretroviral therapy, HIV suppression and preexposure prophylaxis use. The most frequently evaluated syndemic conditions have been depression, substance use and personal experience of abuse or violence; a few studies have included experience of incarceration and unstable housing. SUMMARY: These studies have yielded valuable insights into links between HIV-related outcomes and mental health, experience of violence and abuse, and substance use. But a key feature - and major utility - of the syndemics framework is its potential for examining not only synergistic individual-level risk factors but also the interactions with economic, political and social systems that influence these individual-level factors and thereby shape the HIV epidemic among African-Americans. Research that takes these systems into account is needed to inform policy changes that can help end the HIV epidemic in this population.
Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Negro ou Afro-Americano , Feminino , Infecções por HIV/epidemiologia , Homossexualidade Masculina , Humanos , Masculino , Comportamento Sexual , Transtornos Relacionados ao Uso de Substâncias/complicações , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Sindemia , ViolênciaRESUMO
Chronic obstructive pulmonary disease is a frequent medical condition, mainly triggered by smoking. COPD patients often suffer from heart diseases that can benefit from beta-blocker therapy. However, fear from triggering latent bronchospasm, or from worsening it, leads to under-prescription of these agents. Adequate patient selection is, thus, crucial. Prescription of a cardio-selective beta-blocker is not only reasonably safe in stable COPD patients but it is also beneficial in terms of mortality in those patients with comorbid cardiac diseases. Use of beta-blockers is contra-indicated in the case of decompensated COPD with severe bronchospasm or in poorly controlled asthma. In all cases, close clinical and, sometimes, functional monitoring is mandatory.
Assuntos
Antagonistas Adrenérgicos beta/efeitos adversos , Espasmo Brônquico/induzido quimicamente , Cardiopatias/tratamento farmacológico , Seleção de Pacientes , Doença Pulmonar Obstrutiva Crônica/complicações , Antagonistas Adrenérgicos beta/administração & dosagem , Contraindicações , Volume Expiratório Forçado , Cardiopatias/complicações , Cardiopatias/mortalidade , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de SobrevidaRESUMO
Spinal anesthesia was administered to a patient for the surgical reduction of an inguinal hernia. However, the procedure was complicated by corticotropic insufficiency secondary to the necrosis of a non-secretory hypophyseal adenoma. The clinical presentation is discussed here together with both medical and neurosurgical managements. Etiology and pathophysiological mechanisms of this complication are analyzed in accordance with the most recent of the literature.
Assuntos
Raquianestesia/efeitos adversos , Hipófise/patologia , Adenoma/patologia , Idoso , Humanos , Necrose , Apoplexia Hipofisária/etiologia , Apoplexia Hipofisária/patologia , Neoplasias Hipofisárias/patologiaRESUMO
Finding abnormalities in diagnostic images is a difficult task even for expert radiologists because the normal tissue locations largely outnumber those with suspicious signs which may thus be missed or incorrectly interpreted. For the same reason the design of a Computer-Aided Detection (CADe) system is very complex because the large predominance of normal samples in the training data may hamper the ability of the classifier to recognize the abnormalities on the images. In this paper we present a novel approach for computer-aided detection which faces the class imbalance with a cascade of boosting classifiers where each node is trained by a learning algorithm based on ranking instead of classification error. Such approach is used to design a system (CasCADe) for the automated detection of clustered microcalcifications (µCs), which is a severely unbalanced classification problem because of the vast majority of image locations where no µC is present. The proposed approach was evaluated with a dataset of 1599 full-field digital mammograms from 560 cases and compared favorably with the Hologic R2CAD ImageChecker, one of the most widespread commercial CADe systems. In particular, at the same lesion sensitivity of R2CAD (90%) on biopsy proven malignant cases, CasCADe and R2CAD detected 0.13 and 0.21 false positives per image (FPpi), respectively (p-value=0.09), whereas at the same FPpi of R2CAD (0.21), CasCADe and R2CAD detected 93% and 90% of true lesions respectively (p-value=0.11) thus showing that CasCADe can compete with high-end CADe commercial systems.