The effects of a new grain boundary phase in Ni-Al alloy

In a γ/γ nickel-aluminum alloy, a new phase has been identified along grain boundaries by conventional transmission electron microscopy. This phase is identified to be of the C6Cr23 type structure with lattice parameter 10.48Å, which is approximately three times that of Ni3Al or nickel. This grain boundary precipitate is found to be coherent with the γ phase in one grain. The chemical composition of this grain boundary precipitate is determined by energy dispersive x-ray spectroscopy and parallel electron energy loss spectroscopy. The deformation mechanism of this grain boundary precipitate is investigated on post-mortem specimens which have been carefully deformed by nanoindentation after jet-polishing.published_or_final_versio

Investigating interactions between land use and honey bee - microbiota associations

Dissertação de mestrado em Psicologia (Psicologia da Educação, Desenvolvimento e Aconselhamento), apresentada à Faculdade de Psicologia e de Ciências da Educação da Universidade de Coimbra.Bryant e Smith (2001) desenvolveram um instrumento composto por 12 itens para avaliar comportamentos agressivos, com base no Questionário de Agressividade de Buss-Perry (AQ). Este questionário tornou-se rapidamente um dos instrumentos de avaliação mais populares para medir a agressividade, tendo sido traduzido para várias línguas e estudado em múltiplos contextos culturais. Ao longo do tempo foram propostas distintas versões do instrumento, nomeadamente quanto ao número de itens e de fatores. Em Portugal, os primeiros estudos empíricos sobre as propriedades metodológicas do Questionário de Agressividade (AQ) tiveram lugar, em Coimbra, na década de 1990, com uma versão composta pelos 29 itens desenvolvidos pelos autores do instrumento. O recente projeto dá continuidade ao estudo inicial, mas visando especificamente a construção de uma versão mais curta do mesmo, na linha iniciada por Bryant e Smith (2001). Neste estudo analisa-se a estrutura fatorial e as propriedades psicométricas de uma versão portuguesa da versão abreviada do Questionário de Agressividade, numa amostra de 893 jovens adultos portugueses. Os respondentes integram o Estudo Longitudinal de Coimbra (ELC) cujo início teve lugar no ano académico de 1992-1993, envolvendo uma amostra representativa dos alunos que nessa altura frequentavam o 2º, 4º e 6º anos das Escolas Públicas desse Concelho. Neste estudo usamos os dados da última avaliação efetuada (quinta fase: n= 746). A amostra é composta por 384 homens (51.5%) e 362 mulheres (48.5%). A análise fatorial exploratória revelou uma estrutura de três fatores distinta, portanto, da definida por Buss e Perry (1992). Os três fatores retidos foram denominados, em conformidade com trabalhos anteriores (Irritabilidade, Agressividade física e Hostilidade). A escala Agressividade Verbal, devido ao baixo número de indicadores usados, não emergiu como um fator independente na análise fatorial. A consistência interna para o score total revelou ser boa ( = .82). O score global de agressividade mostrou 4 validade convergente e discriminante relativamente a um conjunto de variáveis derivadas com base na teoria da tensão do comportamento antissocial. Os resultados foram discutidos com base na validação do AQ versão reduzida para 12 itens de (Bryant & Smith, 2001), adaptada para a população portuguesa.Bryant and Smith (2001) developed an instrument composed by 12 items to assess aggressive behavior, based on the Aggression Questionnaire (AQ) of Buss-Perry. This questionnaire has quickly become one of the most popular assessment tools to measure aggression, and had been translated into several languages and studied in multiple cultural contexts. Over time were presented different versions of the instrument, particularly concerning the number of items and factors. In Portugal the first empirical studies of the measurement characteristics of Aggression Questionnaire (AQ) took place in Coimbra, in the 1990s, with a version composed of 29 items. The recent project pretend to follow the original, but specifically assess the construction of a brief version, according to the work of Bryant and Smith (2001). In this study we analyze the factor structure and psychometric properties of a portuguese version of the brief version of the Aggression Questionnaire in a sample of 893 portuguese young adults. Data are part of the Longitudinal Study of Coimbra (LSC) which took place early in the academic year 1992-1993, involving a representative sample of students who attended the 2nd, 4th and 6th years of Coimbra Public Schools. This study used the participants from the last evaluation performed (fifth stage: n= 746). The sample consists of 384 men (51.5%) and 362 women (48.5%). The exploratory factor analysis revealed a three-factor structure distinct, therefore, defined by Buss and Perry (1992). The three factors retained were called, in accordance with previous jobs: (Irritability, Physical Aggressiveness and Hostility). The scale Verbal Aggressiveness, due to the low number of indicators used not emerged as an independent factor in factor analysis. The internal consistency for the total score was found to be good (alpha = .82). The overall score of aggressiveness showed convergent and discriminated validity in relation to a set of derived variables on the basis of the theory of voltage of antisocial behavior. The results were discussed on the basis of the validation of AQ version reduced to 12 items (Bryant and Smith, 2001), adapted to the Portuguese population

Do knee pain phenotypes have different risks of total knee replacement?

Pain is the main impetus for osteoarthritis (OA) patients to seek healthcare including joint replacement. The pain experience in OA is heterogeneous and affected by factors across multiple domains-peripheral, psychological, and neurological. This indicates the existence of homogenous subgroups/phenotypes within OA patients with pain. We recently identified three pain phenotypes using a wide spectrum of pain-related factors, including structural damage on magnetic resonance imaging (MRI), emotional problems, number of painful sites, sex, body mass index, education level and comorbidities (i.e., Class 1: high prevalence of emotional problems and low prevalence of structural damage (25%); Class 2: low prevalence of emotional problems and high prevalence of structural damage (20%); Class 3: low prevalence of emotional problems and low prevalence of structural damage (55%)). This study was to examine whether the total knee replacement (TKR) risk over 12 years was different among these three pain phenotypes. Data on 963 participants (mean age 62.8 ± 7.4 years) from a population-based cohort study were utilised. Data on socio-demographic, psychological and comorbidities were collected. MRI of the right knee structural pathology was performed. TKR history was ascertained by linking to the Australian Orthopedic Association National Joint Replacement Registry. Latent class analysis and the Cox proportional hazards model were applied for the analysis. During the follow-up period, 41 right and 44 left TKRs in 67 participants were identified. In multivariable analyses, participants in Class 1 and 2 had a higher risk of having a TKR (Class 1 vs. Class 3, HR (hazard ratio) 4.81, 95%CI (confidence interval) 2.33-9.93; Class 2 vs. Class 3, HR 9.23, 95%CI 4.66-18.30). These associations were stronger in the imaged right knee but were also significant in the left knee. Participants within distinct pain phenotypes have different risks of TKR, suggesting that the identified phenotypes reflect distinct clinical subgroups with different prognoses. The risk for TKR was higher in Class 1 than that in Class 3, suggesting that pain/emotional status is a stronger driver for TKR than structural damage, and that selecting patients for TKR needs to be optimized in clinical practice

Quantitative SERS Detection of Uric Acid via Formation of Precise Plasmonic Nanojunctions within Aggregates of Gold Nanoparticles and Cucurbit[n]uril

This work describes a rapid and highly sensitive method for the quantitative detection of an important biomarker, uric acid (UA), via surface-enhanced Raman spectroscopy (SERS) with a low detection limit of ~0.2 μM for multiple characteristic peaks in the fingerprint region, using a modular spectrometer. This biosensing scheme is mediated by the host-guest complexation between a macrocycle, cucurbit[7]uril (CB7), and UA, and the subsequent formation of precise plasmonic nanojunctions within the self-assembled Au NP: CB7 nanoaggregates. A facile Au NP synthesis of desirable sizes for SERS substrates has also been performed based on the classical citrate-reduction approach with an option to be facilitated using a lab-built automated synthesizer. This protocol can be readily extended to multiplexed detection of biomarkers in body fluids for clinical applications

TERC polymorphisms are associated both with susceptibility to colorectal cancer and with longer telomeres.

Shorter telomeres have been associated with increased risk of malignancy, including colorectal cancer (CRC). Telomere length is heritable and may be an intermediate phenotype linked to genetic susceptibility to CRC

SERS multiplexing of methylxanthine drug isomers via host-guest size matching and machine learning

Multiplexed detection and quantification of structurally similar drug molecules, methylxanthine MeX, incl. theobromine TBR, theophylline TPH and caffeine CAF, have been demonstrated via solution-based surface-enhanced Raman spectroscopy (SERS), achieving highly reproducible SERS signals with detection limits down to ∼50 nM for TBR and TPH, and ∼1 μM for CAF. Our SERS substrates are formed by aqueous self-assembly of gold nanoparticles (Au NPs) and supramolecular host molecules, cucurbit[n]urils (CBn, n = 7, 8). We demonstrate that the binding constants can be significantly increased using a host–guest size matching approach, which enables effective enrichment of analyte molecules in close proximity to the plasmonic hotspots. The dynamic range and the robustness of the sensing scheme can be extended using machine learning algorithms, which shows promise for potential applications in therapeutic drug monitoring, food processing, forensics and veterinary science

Measures that can be used to teach critical thinking skills in nurse prescribers

Critical thinking is a pervasive skill that involves scrutinizing, differentiating, and appraising information and reflecting on the information gained in order to make judgements and inform clinical decisions. Studies inform us of the need for agreement on the approaches used to teach and measure critical thinking. Nurse prescribers undertake an advanced role that encompass the need to be able to make clinically based decisions about the appropriateness of a specific medication. This requires critical thinking attributes. A variety of teaching and learning approaches are offered which can be used by nurse educators to develop critical thinking skills in nurse prescribers

Three-year findings of the HORIZON trial: a Schlemm canal microstent for pressure reduction in primary open angle glaucoma and cataract

OBJECTIVE: To report 3-year outcomes of the HORIZON study comparing cataract surgery with Hydrus Microstent versus cataract surgery alone. DESIGN: Multicenter randomized clinical trial. PARTICIPANTS: Five hundred fifty-six eyes from 556 patients with cataract and POAG treated with ≥ 1 glaucoma medication, washed out diurnal intraocular pressure (DIOP) 22-34 mmHg and no prior incisional glaucoma surgery. METHODS: Following phacoemulsification, eyes were randomized 2:1 to receive a Hydrus® Microstent (Ivantis, Inc.) or no stent. Follow-up included comprehensive eye examinations through 3 years postoperatively. MAIN OUTCOME MEASURES: Outcome measures included IOP, medical therapy, reoperation rates, visual acuity, adverse events, and changes in corneal endothelial cell counts. RESULTS: 369 eyes were randomized to microstent treatment (HMS) and 187 to cataract surgery only (CS). Preoperative IOP, medication usage, washed out DIOP, and glaucoma severity did not differ between the two treatment groups. At 3 years, IOP was 16.7 ± 3.1 in the HMS group and 17.0 ± 3.4 in the CS group (p=0.85). The number of glaucoma medications was 0.4 ± 0.8 in the HMS group and 0.8 ± 1.0 in the CS group (p<0.001), and 73% of eyes in the HMS group were medication free compared to 48% in the CS group (p<0.001). The HMS group had a higher proportion of eyes with IOP ≤18 mmHg without medications compared to CS (56.2% vs. 34.6%, p<0.001) as well as IOP reduction of at least 20, 30 or 40 percent compared to CS alone. The cumulative probability of incisional glaucoma surgery was lower in the HMS group (0.6% vs. 3.9%, hazard ratio = 0.156, 95% CI 0.031 to 0.773, p=0.020). There was no difference in postoperative corneal endothelial cell loss between groups. There were no procedure or device related serious adverse events resulting in vision loss in either group. CONCLUSIONS: Combined cataract surgery and microstent placement for mild to moderate POAG is safe, more effective in lowering IOP with fewer medications, and less likely to result in further incisional glaucoma filtrations surgery than cataract surgery alone at 3 years

Computer-Aided Design and Analysis of Spectrally Aligned Hybrid Plasmonic Nanojunctions for SERS Detection of Nucleobases

Hybrid plasmonic nanojunctions with optimal surface-enhanced Raman scattering (SERS) activity are designed via a computer-aided approach, and fabricated via time-controlled aqueous self-assembly of core@shell gold@silver nanoparticles (Au@Ag NPs) with cucurbit[7]uril (CB7) upon simple mixing. The authors showed that SERS signals can be significantly boosted by the incorporation of a strong plasmonic metal and the spectral alignment between the maximal localized surface plasmon resonance (LSPR) and a laser wavelength used for SERS excitation. In a proof-of-concept application, SERS detection of nucleobases with a 633-nm laser has been demonstrated by positioning them within the nanojunctions via formation of host–guest complexes with CB7, achieving rapid response with a detection limit down to sub-nanomolar concentration and an enhancement factor (EF) up to ≈109–1010, i.e., the minimum required EF for single-molecule detection. Furthermore, machine-learning-driven multiplexing of nucleobases is demonstrated, which shows promise in point-of-care diagnosis of diseases related to oxidative damage of DNA and wastewater-based epidemiology