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1.
Mol Psychiatry ; 28(8): 3171-3181, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37580524

RESUMO

Most mental disorders have a typical onset between 12 and 25 years of age, highlighting the importance of this period for the pathogenesis, diagnosis, and treatment of mental ill-health. This perspective addresses interactions between risk and protective factors and brain development as key pillars accounting for the emergence of psychopathology in youth. Moreover, we propose that novel approaches towards early diagnosis and interventions are required that reflect the evolution of emerging psychopathology, the importance of novel service models, and knowledge exchange between science and practitioners. Taken together, we propose a transformative early intervention paradigm for research and clinical care that could significantly enhance mental health in young people and initiate a shift towards the prevention of severe mental disorders.


Assuntos
Transtornos Mentais , Saúde Mental , Humanos , Adolescente , Transtornos Mentais/terapia , Transtornos Mentais/diagnóstico , Psicopatologia
2.
Adv Mater ; 35(24): e2212042, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36934307

RESUMO

Solution-processed graphene is a promising material for numerous high-volume applications including structural composites, batteries, sensors, and printed electronics. However, the polydisperse nature of graphene dispersions following liquid-phase exfoliation poses major manufacturing challenges, as incompletely exfoliated graphite flakes must be removed to achieve optimal properties and downstream performance. Incumbent separation schemes rely on centrifugation, which is highly energy-intensive and limits scalable manufacturing. Here, cross-flow filtration (CFF) is introduced as a centrifuge-free processing method that improves the throughput of graphene separation by two orders of magnitude. By tuning membrane pore sizes between microfiltration and ultrafiltration length scales, CFF can also be used for efficient recovery of solvents and stabilizing polymers. In this manner, life cycle assessment and techno-economic analysis reveal that CFF reduces greenhouse gas emissions, fossil energy usage, water consumption, and specific production costs of graphene manufacturing by 57%, 56%, 63%, and 72%, respectively. To confirm that CFF produces electronic-grade graphene, CFF-processed graphene nanosheets are formulated into printable inks, leading to state-of-the-art thin-film conductivities exceeding 104 S m-1 . This CFF methodology can likely be generalized to other van der Waals layered solids, thus enabling sustainable manufacturing of the diverse set of applications currently being pursued for 2D materials.

3.
Neuropsychopharmacology ; 47(2): 524-530, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33833403

RESUMO

Matrix metalloproteinases 9 (MMP9) are enzymes involved in regulating neuroplasticity in the hippocampus. This, combined with evidence for disrupted hippocampal structure and function in schizophrenia, has prompted our current investigation into the relationship between MMP9 and hippocampal volumes in schizophrenia. 34 healthy individuals (mean age = 32.50, male = 21, female = 13) and 30 subjects with schizophrenia (mean age = 33.07, male = 19, female = 11) underwent a blood draw and T1-weighted magnetic resonance imaging. The hippocampus was automatically segmented utilizing FreeSurfer. MMP9 plasma levels were measured with ELISA. ANCOVAs were conducted to compare MMP9 plasma levels (corrected for age and sex) and hippocampal volumes between groups (corrected for age, sex, total intracranial volume). Spearman correlations were utilized to investigate the relationship between symptoms, medication, duration of illness, number of episodes, and MMP9 plasma levels in patients. Last, we explored the correlation between MMP9 levels and hippocampal volumes in patients and healthy individuals separately. Patients displayed higher MMP9 plasma levels than healthy individuals (F(1, 60) = 21.19, p < 0.0001). MMP9 levels correlated with negative symptoms in patients (R = 0.39, p = 0.035), but not with medication, duration of illness, or the number of episodes. Further, patients had smaller left (F(1,59) = 9.12, p = 0.0040) and right (F(1,59) = 6.49, p = 0.013) hippocampal volumes. Finally, left (R = -0.39, p = 0.034) and right (R = -0.37, p = 0.046) hippocampal volumes correlated negatively with MMP9 plasma levels in patients. We observe higher MMP9 plasma levels in SCZ, associated with lower hippocampal volumes, suggesting involvement of MMP9 in the pathology of SCZ. Future studies are needed to investigate how MMP9 influences the pathology of SCZ over the lifespan, whether the observed associations are specific for schizophrenia, and if a therapeutic modulation of MMP9 promotes neuroprotective effects in SCZ.


Assuntos
Metaloproteinase 9 da Matriz , Esquizofrenia , Adulto , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Metaloproteinase 9 da Matriz/uso terapêutico , Esquizofrenia/tratamento farmacológico
4.
Adv Mater ; 34(3): e2106402, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34731506

RESUMO

LiNiO2 (LNO) is a promising cathode material for next-generation Li-ion batteries due to its exceptionally high capacity and cobalt-free composition that enables more sustainable and ethical large-scale manufacturing. However, its poor cycle life at high operating voltages over 4.1 V impedes its practical use, thus motivating efforts to elucidate and mitigate LiNiO2 degradation mechanisms at high states of charge. Here, a multiscale exploration of high-voltage degradation cascades associated with oxygen stacking chemistry in cobalt-free LiNiO2 , is presented. Lattice oxygen loss is found to play a critical role in the local O3-O1 stacking transition at high states of charge, which subsequently leads to Ni-ion migration and irreversible stacking faults during cycling. This undesirable atomic-scale structural evolution accelerates microscale electrochemical creep, cracking, and even bending of layers, ultimately resulting in macroscopic mechanical degradation of LNO particles. By employing a graphene-based hermetic surface coating, oxygen loss is attenuated in LNO at high states of charge, which suppresses the initiation of the degradation cascade and thus substantially improves the high-voltage capacity retention of LNO. Overall, this study provides mechanistic insight into the high-voltage degradation of LNO, which will inform ongoing efforts to employ cobalt-free cathodes in Li-ion battery technology.

5.
Sci Rep ; 9(1): 6871, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053725

RESUMO

A diverse microbiota exists within the airways of individuals with non-cystic fibrosis bronchiectasis (nCFB). How the lung microbiome evolves over time, and whether changes within the microbiome correlate with future disease progression is not yet known. We assessed the microbial community structure of 133 serial sputa and subsequent disease course of 29 nCFB patients collected over a span of 4-16 years using 16S rRNA paired-end sequencing. Interestingly, no significant shifts in the microbial community of individuals were observed during extended follow-up suggesting the microbiome remains relatively stable over prolonged periods. Samples that were Pseudomonas aeruginosa culture positive displayed markedly different microbial community structures compared to those that were positive for Haemophilus influenzae. Importantly, patients with sputum of lower microbial community diversity were more likely to experience subsequent lung function decline as defined by annual change in ≥-1 FEV1% predicted. Shannon diversity values <1 were more prevalent in patients with FEV1 decline (P = 0.002). However, the relative abundance of particular core microbiota constituents did not associate with risk of decline. Here we present data confirming that the microbiome of nCFB individuals is generally stable, and that microbiome-based measurements may have a prognostic role as biomarkers for nCFB.


Assuntos
Brônquios/microbiologia , Bronquiectasia/microbiologia , Microbiota , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bronquiectasia/tratamento farmacológico , Feminino , Humanos , Estudos Longitudinais , Masculino , Microbiota/efeitos dos fármacos , Pessoa de Meia-Idade
6.
Med Biol Eng Comput ; 57(2): 489-503, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30232700

RESUMO

In common radiography, image contrast is often limited due mainly to scattered x-rays and noise, decreasing the quantitative usefulness of x-ray images. Several scatter reduction methods based on software correction schemes have been extensively investigated in an attempt to overcome these difficulties, most of which are based on measurement, mathematical-physical modeling, or a combination of both. However, those methods require special equipment, system geometry, and extra manual work to measure scatter characteristics. In this study, we investigated a new software scheme for scatter correction based on a simple radiographic scattering model where the intensity of the scattered x-rays was directly estimated from a single x-ray image using a weighted l1-norm contextual regularization framework. We implemented the proposed algorithm and performed a systematic simulation and experiment to demonstrate its viability. We also conducted some clinical image studies using patient's image data of breast and L-spine to verify the clinical effectiveness of the proposed scheme. Our results indicate that the degradation of image characteristics by scattered x-rays and noise was effectively recovered by using the proposed software scheme, thus improving radiographic visibility considerably. Graphical abstract The schematic illustrations of scatter suppression methods by using a an antiscatter grid and b a scatter estimation algorithm.


Assuntos
Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Humanos , Imagens de Fantasmas , Intensificação de Imagem Radiográfica/métodos , Espalhamento de Radiação , Software , Raios X
7.
J Digit Imaging ; 32(3): 478-488, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30238344

RESUMO

In cone-beam computed tomography (CBCT), reconstructed images are inherently degraded, restricting its image performance, due mainly to imperfections in the imaging process resulting from detector resolution, noise, X-ray tube's focal spot, and reconstruction procedure as well. Thus, the recovery of CBCT images from their degraded version is essential for improving image quality. In this study, we investigated a compressed-sensing (CS)-based blind deconvolution method to solve the blurring problem in CBCT where both the image to be recovered and the blur kernel (or point-spread function) of the imaging system are simultaneously recursively identified. We implemented the proposed algorithm and performed a systematic simulation and experiment to demonstrate the feasibility of using the algorithm for image deblurring in dental CBCT. In the experiment, we used a commercially available dental CBCT system that consisted of an X-ray tube, which was operated at 90 kVp and 5 mA, and a CMOS flat-panel detector with a 200-µm pixel size. The image characteristics were quantitatively investigated in terms of the image intensity, the root-mean-square error, the contrast-to-noise ratio, and the noise power spectrum. The results indicate that our proposed method effectively reduced the image blur in dental CBCT, excluding repetitious measurement of the system's blur kernel.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Compressão de Dados/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Radiografia Dentária/métodos , Algoritmos , Desenho de Equipamento , Humanos , Imagens de Fantasmas
8.
Nat Commun ; 9(1): 4095, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30291247

RESUMO

Directed placement of solution-based nanomaterials at predefined locations with nanoscale precision limits bottom-up integration in semiconductor process technology. We report a method for electric-field-assisted placement of nanomaterials from solution by means of large-scale graphene layers featuring nanoscale deposition sites. The structured graphene layers are prepared via either transfer or synthesis on standard substrates, and then are removed once nanomaterial deposition is completed, yielding material assemblies with nanoscale resolution that cover surface areas >1 mm2. In order to demonstrate the broad applicability, we have assembled representative zero-dimensional, one-dimensional, and two-dimensional semiconductors at predefined substrate locations and integrated them into nanoelectronic devices. Ultimately, this method opens a route to bottom-up integration of nanomaterials for industry-scale applications.

9.
Br J Anaesth ; 121(4): 758-767, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30236238

RESUMO

BACKGROUND: We investigated potential for hypersensitivity reactions after repeated sugammadex administration and explored the mechanism of hypersensitivity. METHODS: In this double-blind, placebo-controlled study (NCT00988065), 448 healthy volunteers were randomised to one of three arms to receive three repeat i.v. administrations of either sugammadex 4 mg kg-1, 16 mg kg-1, or placebo. Primary endpoint was percentage of subjects with hypersensitivity (assessed by an independent adjudication committee). Secondary endpoint of anaphylaxis was classified per Sampson and Brighton criteria. Exploratory endpoints included skin testing, serum tryptase, anti-sugammadex antibodies [immunoglobulin (Ig) E/IgG], and other immunologic parameters. RESULTS: Hypersensitivity was adjudicated for 1/148 (0.7%), 7/150 (4.7%), and 0/150 (0.0%) subjects after sugammadex 4 mg kg-1, 16 mg kg-1, and placebo, respectively. After sugammadex 16 mg kg-1, one subject met Sampson criterion 1 and Brighton level 1 (highest certainty) anaphylaxis criteria; two met Brighton level 2 criteria. After database lock it was determined that certain protocol deviations could have introduced bias in the reporting of hypersensitivity signs/symptoms in a subject subset. Objective laboratory investigations indicated that potential underlying hypersensitivity mechanisms were unlikely to have been activated; the results suggest that most of the observed hypersensitivity reactions were unlikely IgE/IgG-mediated. CONCLUSION: Dose-dependent hypersensitivity or anaphylaxis reactions to sugammadex were observed when administered without prior neuromuscular blocking agent. Laboratory investigations do not suggest prevalent allergen-specific IgE/IgG-mediated immunologic hypersensitivity. Because it could not be fully excluded that estimates of hypersensitivity/anaphylaxis incidence were unbiased, an additional study was conducted to characterise the potential for hypersensitivity reactions and is described in a companion report. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov NCT00988065; Protocol number P06042.


Assuntos
Hipersensibilidade a Drogas/imunologia , Sugammadex/efeitos adversos , Administração Intravenosa , Adolescente , Adulto , Anafilaxia/imunologia , Anticorpos/imunologia , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Segurança , Testes Cutâneos , Sugammadex/administração & dosagem , Triptases/sangue , Adulto Jovem
10.
Br J Anaesth ; 121(4): 749-757, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30236237

RESUMO

BACKGROUND: We evaluated the incidence of hypersensitivity or anaphylaxis after repeated single-dose sugammadex administration in non-anaesthetised adults. METHODS: In this multicentre, double-blind study (NCT02028065), healthy volunteer subjects were randomised (2:2:1 ratio) to one of three groups to receive three repeated intravenous injections of sugammadex 4 or 16 mg kg-1, or placebo, separated by a ∼5 week intervals. Targeted hypersensitivity assessments were performed 0.5, 4, and 24 h post-dosing, and hypersensitivity signs/symptoms were referred to a blinded independent Adjudication Committee. Anaphylaxis was determined per Sampson (Criterion 1). The primary endpoint was the proportion with confirmed hypersensitivity. RESULTS: Of 375 evaluable subjects, 25 had confirmed hypersensitivity [sugammadex 4 mg kg-1: 10/151 (6.6%); sugammadex 16 mg kg-1: 14/148 (9.5%); placebo: 1/76 (1.3%)]. The differences in incidence rates vs placebo were 5.3% (95% confidence interval: -0.9, 10.7) for sugammadex 4 mg kg-1 and 8.1% (1.7, 14.2) for 16 mg kg-1. Incidence was similar across sugammadex doses and dosing occasions, including in subjects with reactions to previous doses. Three subjects (16 mg kg-1 group) required antihistamines/corticosteroids and discontinued the study, per protocol; symptoms resolved and no subject required epinephrine. One subject with anaphylaxis after the first 16 mg kg-1 dose recovered completely post-treatment. There were no clinically relevant anti-sugammadex antibody or tryptase findings. CONCLUSIONS: Hypersensitivity in response to sugammadex administration can occur in healthy subjects without history of previous sugammadex exposure. Hypersensitivity incidence was similar across sugammadex doses and numerically higher than placebo, with no evidence of sensitisation with repeated administration. Hypersensitivity is unlikely to be mediated through sugammadex-specific immunoglobulin G- or E-mediated mast cell stimulation in healthy volunteers. CLINICAL TRIAL REGISTRATION: NCT02028065.


Assuntos
Hipersensibilidade a Drogas/epidemiologia , Sugammadex/efeitos adversos , Corticosteroides/uso terapêutico , Adulto , Anafilaxia/epidemiologia , Anafilaxia/etiologia , Anticorpos/análise , Método Duplo-Cego , Hipersensibilidade a Drogas/tratamento farmacológico , Feminino , Voluntários Saudáveis , Antagonistas dos Receptores Histamínicos/uso terapêutico , Humanos , Imunoglobulina E/análise , Imunoglobulina G/análise , Incidência , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Triptases/sangue , Adulto Jovem
11.
Forensic Sci Int ; 291: 17-22, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30125767

RESUMO

If an automobile happens to crash into the back of another vehicle while travelling at high speeds, both vehicles will be seriously damaged. Consequently, it is not easy to reconstruct the initial collision state between the two vehicles or determine whether or not the risk perception of the driver is normal. The entire picture of the accident cannot be fully understood and thus clarifying the relevant legal responsibility is difficult. The trace evidence of tires, such as pattern, direction, and impression examination as well as other characteristics, can be carefully observed and used as evidence in accident reconstruction. A case report of a fatal collision involving a bus crashing into the frame of a full trailer on a freeway is examined in this study. The police agency used the characteristics of the trace evidence of the bus tires to reconstruct the initial collision state of the two vehicles to clarify the cause of the accident, and these determination guidelines can be used by police while handling similar cases in the future. This case uses new information regarding the initial collision state of road traffic accidents for reconstruction and provides knowledge and interest for the forensic community.

12.
Comput Biol Med ; 97: 74-82, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29709716

RESUMO

In this study, we propose a modification to a single-grid phase-contrast x-ray imaging (PCXI) system using a Fourier domain analysis technique to extract absorption, scattering, and differential phase-contrast images. The proposed modification is to rotate the x-ray grid in the image plane to achieve spectral separation between the desired information and the moiré artifact, which is introduced by the superposition of the periodic image of the grid shadow and the periodic sampling by the detector. In addition, we performed some system optimization by adjusting distances between source, object, grid, and detector to further improve image quality. This optimization aimed to increase the spectral spacing between the primary spectrum (lower frequency) and the harmonics of the spectrum (higher frequency) used to extract the various image contrasts. The table-top setup used in the experiment consisted of a focused-linear grid with a 200-lines/inch strip density, a microfocus x-ray tube with a 55-µm focal spot size, and a CMOS flat-panel detector with a 49.5-µm pixel size. The x-ray grid was rotated at 27.8° with respect to the detector and the sample was placed as close as possible to the x-ray tube. Our results indicated that the proposed method effectively eliminated the PCXI artifacts, thus improving image quality.


Assuntos
Artefatos , Análise de Fourier , Intensificação de Imagem Radiográfica/métodos , Animais , Desenho de Equipamento , Peixes , Modelos Biológicos
13.
Skeletal Radiol ; 47(9): 1221-1228, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29497774

RESUMO

BACKGROUND: The ring apophyses of the cervical spine have a variable appearance that changes with age. The times at which they appear and fuse at each level are not fixed. In this study, we aim to detail normal ranges of appearance of these ossification centers for each age group. MATERIALS AND METHODS: One hundred and eighty patients under the age of 21 attending the Royal Stoke University Hospital for cervical spine radiographs were retrospectively identified. The presence or absence of ring apophyses at each cervical level and whether these had undergone fusion was reported, as were the thickness, length, and craniocaudal and anteroposterior distance of the apophysis from the vertebral body. The angulation of the apophysis relative to the endplate was also noted. RESULTS: The youngest patient in which apophyses were seen was aged 3, but apophyses were otherwise rarely seen before the age of 6. All apophyses were present from age 14, and the superior apophyses fused by the age of 18, although unfused inferior apophyses were still seen in the 20-year age group. It was observed that apophyses were rarely separated from the vertebral body by greater than 1 mm in craniocaudal distance (1%) or 2.5 mm in anteroposterior distance (2.6%) and the anterior apophysis was angulated towards the endplate in only 1% of cases. CONCLUSIONS: We have detailed the range of normal appearances of the ring apophyses of the developing cervical spine. Cervical spine apophyseal injury is thought to be rare, but knowledge of normative morphological features should help in this diagnosis.


Assuntos
Desenvolvimento Ósseo , Vértebras Cervicais/diagnóstico por imagem , Adolescente , Fatores Etários , Vértebras Cervicais/anatomia & histologia , Criança , Pré-Escolar , Humanos , Radiografia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Traumatismos da Coluna Vertebral/diagnóstico , Adulto Jovem
14.
Handb Clin Neurol ; 150: 181-196, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29496141

RESUMO

Postmortem studies on the human brain reside at the core of investigations on neurologic and psychiatric disorders. Ground-breaking advances continue to be made on the pathologic basis of many of these disorders, at molecular, cellular, and neural connectivity levels. In parallel, there is increasing emphasis on improving methods to extract relevant demographic and clinical information about brain donors and, importantly, translate it into measures that can reliably and effectively be incorporated in the design and data analysis of postmortem human investigations. Here, we review the main source of information typically available to brain banks and provide examples on how this information can be processed. In particular, we discuss approaches to establish primary and secondary diagnoses, estimate exposure to therapeutic treatment and substance abuse, assess agonal status, and use time of death as a proxy in investigations on circadian rhythms. Although far from exhaustive, these considerations are intended as a contribution to ongoing efforts from tissue banks and investigators aimed at establishing robust, well-validated methods for collecting and standardizing information about brain donors, further strengthening the scientific rigor of human postmortem studies.


Assuntos
Encéfalo/patologia , Diagnóstico , Transtornos Mentais/diagnóstico , Doenças do Sistema Nervoso/diagnóstico , Projetos de Pesquisa , Bancos de Tecidos , Humanos , Doadores de Tecidos
15.
Schizophr Bull ; 44(2): 317-327, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29462456

RESUMO

Biomarker-guided treatments are needed in psychiatry, and previous data suggest oxidative stress may be a target in schizophrenia. A previous add-on trial with the antioxidant N-acetylcysteine (NAC) led to negative symptom reductions in chronic patients. We aim to study NAC's impact on symptoms and neurocognition in early psychosis (EP) and to explore whether glutathione (GSH)/redox markers could represent valid biomarkers to guide treatment. In a double-blind, randomized, placebo-controlled trial in 63 EP patients, we assessed the effect of NAC supplementation (2700 mg/day, 6 months) on PANSS, neurocognition, and redox markers (brain GSH [GSHmPFC], blood cells GSH levels [GSHBC], GSH peroxidase activity [GPxBC]). No changes in negative or positive symptoms or functional outcome were observed with NAC, but significant improvements were found in favor of NAC on neurocognition (processing speed). NAC also led to increases of GSHmPFC by 23% (P = .005) and GSHBC by 19% (P = .05). In patients with high-baseline GPxBC compared to low-baseline GPxBC, subgroup explorations revealed a link between changes of positive symptoms and changes of redox status with NAC. In conclusion, NAC supplementation in a limited sample of EP patients did not improve negative symptoms, which were at modest baseline levels. However, NAC led to some neurocognitive improvements and an increase in brain GSH levels, indicating good target engagement. Blood GPx activity, a redox peripheral index associated with brain GSH levels, could help identify a subgroup of patients who improve their positive symptoms with NAC. Thus, future trials with antioxidants in EP should consider biomarker-guided treatment.


Assuntos
Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Biomarcadores , Disfunção Cognitiva/tratamento farmacológico , Glutationa/efeitos dos fármacos , Avaliação de Resultados em Cuidados de Saúde , Córtex Pré-Frontal/efeitos dos fármacos , Transtornos Psicóticos/tratamento farmacológico , Esquizofrenia/tratamento farmacológico , Acetilcisteína/administração & dosagem , Adolescente , Adulto , Antioxidantes/administração & dosagem , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Método Duplo-Cego , Feminino , Glutationa Peroxidase , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Oxirredução , Córtex Pré-Frontal/metabolismo , Transtornos Psicóticos/complicações , Transtornos Psicóticos/metabolismo , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/complicações , Esquizofrenia/metabolismo , Esquizofrenia/fisiopatologia , Adulto Jovem
16.
BMC Geriatr ; 17(1): 264, 2017 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29132301

RESUMO

BACKGROUND: The objectives of this study were to determine: 1) the prevalence of frailty using Fried's phenotype method and the Short Performance Physical Battery (SPPB), 2) agreement between frailty assessment methods, 3) the feasibility of assessing frailty using Fried's phenotype method and the SPPB. METHODS: This cross-sectional study was conducted at a geriatric out-patient clinic in Hamilton, Canada. A research assistant conducted all frailty assessments. Patients were classified as non-frail, pre-frail or frail according to Fried's phenotype method and the SPPB. Agreement among methods is reported using the Cohen kappa statistic (standard error). Feasibility data included the percent of eligible participants agreeing to attempt the frailty assessments (criterion for feasibility: ≥90% of patients agreeing to the frailty assessment), equipment required, and safety considerations. A p-value of <0.05 is considered significant. RESULTS: A total of 110 participants (92%) and 109 participants (91%) agreed to attempt Fried's phenotype method and SPPB, respectively. No adverse events occurred during any assessments. According to Fried's phenotype method, the prevalence of frailty and pre-frailty was 35% and 56%, respectively, and according to the SPPB, the prevalence of frailty and pre-frailty was 50% and 35%, respectively. There was fair to moderate agreement between methods for determining which participants were frail (0.488 [0.082], p < 0.001) and pre-frail (0.272 [0.084], p = 0.002). CONCLUSIONS: Frailty and pre-frailty are common in this geriatric outpatient population, and there is fair to moderate agreement between Fried's phenotype method and the SPPB. Over 90% of the patients who were eligible for the study agreed to attempt the frailty assessments, demonstrating that according to our feasibility criteria, frailty can be assessed in this patient population. Assessing frailty may help clinicians identify high-risk patients and tailor interventions based on baseline frailty characteristics.


Assuntos
Idoso Fragilizado , Fragilidade/diagnóstico , Avaliação Geriátrica/métodos , Serviços de Saúde para Idosos/normas , Ambulatório Hospitalar/normas , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Estudos de Coortes , Estudos Transversais , Feminino , Fragilidade/epidemiologia , Humanos , Masculino
17.
Nano Lett ; 17(4): 2539-2546, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28240911

RESUMO

Efficient energy storage systems based on lithium-ion batteries represent a critical technology across many sectors including consumer electronics, electrified transportation, and a smart grid accommodating intermittent renewable energy sources. Nanostructured electrode materials present compelling opportunities for high-performance lithium-ion batteries, but inherent problems related to the high surface area to volume ratios at the nanometer-scale have impeded their adoption for commercial applications. Here, we demonstrate a materials and processing platform that realizes high-performance nanostructured lithium manganese oxide (nano-LMO) spinel cathodes with conformal graphene coatings as a conductive additive. The resulting nanostructured composite cathodes concurrently resolve multiple problems that have plagued nanoparticle-based lithium-ion battery electrodes including low packing density, high additive content, and poor cycling stability. Moreover, this strategy enhances the intrinsic advantages of nano-LMO, resulting in extraordinary rate capability and low temperature performance. With 75% capacity retention at a 20C cycling rate at room temperature and nearly full capacity retention at -20 °C, this work advances lithium-ion battery technology into unprecedented regimes of operation.

18.
J Frailty Aging ; 5(2): 88-99, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27224499

RESUMO

Sarcopenia is a multi-faceted geriatric syndrome that is prevalent in the older population. It is an independent risk factor for a variety of devastating health outcomes that threaten the independence of older people. Quality of life is also very important to older people. The objective of this systematic review therefore was to determine the relationship between the biomarkers of sarcopenia (or sarcopenia) and health related quality of life in older people. Systematic searches were done using the electronic databases from MEDLINE and EMBASE. Search terms included sarcopenia, biomarkers of sarcopenia (e.g. muscle mass, grip strength, muscle performance), and health related quality of life. A total of 20 studies were finally included in this review. Only four studies were deemed of good quality. Sarcopenia was associated with poor health related quality of life in both genders from the one cross sectional study defining sarcopenia as per consensus definition. One high quality longitudinal study demonstrated that better physical performance and muscle strength was associated with a slower rate of decline in health related quality of life over six years. Muscle performance and strength were associated with health related quality of life but muscle mass was not in cross-sectional studies. Good quality and longitudinal studies where sarcopenia is defined as per consensus guidelines are required if the impact of the disease on quality of life is to be clarified.


Assuntos
Envelhecimento , Biomarcadores/análise , Qualidade de Vida , Sarcopenia , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Avaliação Geriátrica/métodos , Humanos , Sarcopenia/diagnóstico , Sarcopenia/psicologia
19.
Nanotechnology ; 27(7): 075601, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26762929

RESUMO

Low-temperature scanning gate microscopy (LT-SGM) studies of graphene allow one to obtain important spatial information regarding coherent transport such as weak localization (WL) and universal conductance fluctuations. Although fascinating LT-SGM results on pristine graphene prepared by mechanical exfoliation have been reported in the literature, there appears to be a dearth of LT-SGM results on chemical vapor deposition (CVD)-grown graphene whose large scale and flexible substrate transferability make it an ideal candidate for coherent electronic applications. To this end, we have performed LT-SGM studies on CVD-grown graphene wide constriction (0.8 µm), which can be readily prepared by cost-effective optical lithography fully compatible with those in wafer foundry, in the WL regime. We find that the movable local gate can sensitively modulate the total conductance of the CVD graphene constriction possibly due to the intrinsic grain boundaries and merged domains, a great advantage for applications in coherent electronics. Moreover, such a conductance modulation by LT-SGM provides an additional, approximately magnetic-field-independent probe for studying coherent transport such as WL in graphene and spatial conductance variation.

20.
Phys Med ; 32(1): 213-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26494155

RESUMO

In this work, we propose a practical method that can combine the two functionalities of dental panoramic and cone-beam CT (CBCT) features in one by using a single panoramic detector. We implemented a CS-based reconstruction algorithm for the proposed method and performed a systematic simulation to demonstrate its viability for 3D dental X-ray imaging. We successfully reconstructed volumetric images of considerably high accuracy by using a panoramic detector having an active area of 198.4 mm × 6.4 mm and evaluated the reconstruction quality as a function of the pitch (p) and the angle step (Δθ). Our simulation results indicate that the CS-based reconstruction almost completely recovered the phantom structures, as in CBCT, for p≤2.0 and θ≤6°, indicating that it seems very promising for accurate image reconstruction even for large-pitch and few-view data. We expect the proposed method to be applicable to developing a cost-effective, volumetric dental X-ray imaging system.


Assuntos
Tomografia Computadorizada de Feixe Cônico/métodos , Imageamento Tridimensional/métodos , Boca/diagnóstico por imagem , Radiografia Dentária/métodos , Algoritmos , Simulação por Computador , Análise Custo-Benefício , Compressão de Dados , Humanos , Modelos Teóricos , Imagens de Fantasmas , Interpretação de Imagem Radiográfica Assistida por Computador , Reprodutibilidade dos Testes , Dente/diagnóstico por imagem , Raios X
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