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1.
Phys Rev Lett ; 131(3): 030602, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540850

RESUMO

Neutral atoms are a promising platform for scalable quantum computing, however, prior demonstration of high fidelity gates or low-loss readout methods have employed restricted numbers of qubits. Using randomized benchmarking of microwave-driven single-qubit gates, we demonstrate average gate errors of 7(2)×10^{-5} on a 225 site atom array using conventional, destructive readout. We further demonstrate a factor of 1.7 suppression of the primary measurement errors via low-loss, nondestructive, and state-selective readout on 49 sites while achieving gate errors of 2(9)×10^{-4}.

2.
Scand J Med Sci Sports ; 33(12): 2470-2481, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37787091

RESUMO

Studies examining the effect of protein (PRO) feeding on post resistance exercise (RE) muscle protein synthesis (MPS) have primarily been performed in men, and little evidence is available regarding the quantity of PRO required to maximally stimulate MPS in trained women following repeated bouts of RE. We therefore quantified acute (4 h and 8 h) and extended (24 h) effects of two bouts of resistance exercise, alongside protein-feeding, in women, and the PRO requirement to maximize MPS. Twenty-four RE trained women (26.6 ± 0.7 years, mean ± SEM) performed two bouts of whole-body RE (3 × 8 repetitions/maneuver at 75% 1-repetition maximum) 4 h apart, with post-exercise ingestion of 15 g, 30 g, or 60 g whey PRO (n = 8/group). Saliva, venous blood, and a vastus lateralis muscle biopsy were taken at 0 h, 4 h, 8 h, and 24 h post-exercise. Plasma leucine and branched chain amino acids were quantified using gas chromatography mass spectrometry (GC-MS) after ingestion of D2 O. Fifteen grams PRO did not alter plasma leucine concentration or myofibrillar synthetic rate (MyoFSR). Thirty and sixty grams PRO increased plasma leucine concentration above baseline (105.5 ± 5.3 µM; 120.2 ± 7.4 µM, respectively) at 4 h (151.5 ± 8.2 µM, p < 0.01; 224.8 ± 16.0 µM, p < 0.001, respectively) and 8 h (176.0 ± 7.3 µM, p < 0.001; 281.7 ± 21.6 µM, p < 0.001, respectively). Ingestion of 30 g PRO increased MyoFSR above baseline (0.068 ± 0.005%/h) from 0 to 4 h (0.140 ± 0.021%/h, p < 0.05), 0 to 8 h (0.121 ± 0.012%/h, p < 0.001), and 0 to 24 h (0.099 ± 0.011%/h, p < 0.01). Ingestion of 60 g PRO increased MyoFSR above baseline (0.063 ± 0.003%/h) from 0 to 4 h (0.109 ± 0.011%/h, p < 0.01), 0 to 8 h (0.093 ± 0.008%/h, p < 0.01), and 0 to 24 h (0.086 ± 0.006%/h, p < 0.01). Post-exercise ingestion of 30 g or 60 g PRO, but not 15 g, acutely increased MyoFSR following two consecutive bouts of RE and extended the anabolic window over 24 h. There was no difference between the 30 g and 60 g responses.


Assuntos
Treinamento Resistido , Masculino , Humanos , Feminino , Leucina/metabolismo , Leucina/farmacologia , Proteínas do Soro do Leite , Músculo Esquelético/metabolismo , Proteínas Musculares/metabolismo
3.
BMC Womens Health ; 19(1): 34, 2019 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30764813

RESUMO

BACKGROUND: Epidemiological research suggests an interrelationship between mental health problems and the (re)occurrence of intimate partner violence (IPV). However, little is known about the impact of mental health treatments on IPV victimization or perpetration, especially in low- and middle-income countries (LMIC). METHODS: We conducted a systematic review to identify prospective, controlled studies of mental health treatments in LMIC. We defined 'mental health treatment' as an intervention for individuals experiencing mental ill health (including substance misuse) including a substantial psychosocial or pharmacological component. Studies had to measure a mental health and IPV outcome. We searched across multi-disciplinary databases using a structured search strategy. Screening of title/abstracts and full-text eligibility assessments were conducted by two researchers independently, data were extracted using a piloted spreadsheet, and a narrative synthesis was generated. RESULTS: We identified seven studies reported in 11 papers conducted in five middle-income countries. With the exception of blinding, studies overall showed acceptable levels of risk of bias. Four of the seven studies focused on dedicated mental health treatments in various populations, including: common mental disorders in earthquake survivors; depression in primary care; alcohol misuse in men; and alcohol misuse in female adult sex workers. The dedicated mental health treatments targeting depression or alcohol misuse consistently reduced levels of these outcomes. The two studies targeting depression also reduced short-term IPV, but no IPV benefits were identified in the two alcohol-focused studies. The other three studies evaluated integrated interventions, in which a focus on substance misuse was part of efforts to reduce HIV/AIDS and violence against particularly vulnerable women. In contrast to the dedicated mental health interventions, the integrated interventions did not consistently reduce mental ill health or alcohol misuse compared to control conditions. CONCLUSIONS: Too few studies have been conducted to judge whether mental health treatments may provide a beneficial strategy to prevent or reduce IPV in LMIC. Key future research questions include: whether promising initial evidence on the effects of depression interventions on reducing IPV hold more broadly, the required intensity of mental health components in integrated interventions, and the identification of mechanisms of IPV that are amenable to mental health intervention.


Assuntos
Vítimas de Crime/psicologia , Vítimas de Crime/estatística & dados numéricos , Violência por Parceiro Íntimo/prevenção & controle , Violência por Parceiro Íntimo/psicologia , Transtornos Mentais/terapia , Pobreza/psicologia , Pobreza/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
4.
BMC Health Serv Res ; 19(1): 262, 2019 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-31036002

RESUMO

BACKGROUND: There is mounting evidence supporting the effectiveness of task-shifted mental health interventions in low- and middle-income countries (LMIC). However, there has been limited systematic scale-up or sustainability of these programs, indicating a need to study implementation. One barrier to progress is a lack of locally relevant and valid implementation measures. We adapted an existing brief dissemination and implementation (D&I) measure which includes scales for acceptability, appropriateness, feasibility and accessibility for local use and studied its validity and reliability among a sample of consumers in Ukraine. METHODS: Local qualitative data informed adaptation of the measure and development of vignettes to test the reliability and validity. Participants were veterans and internally displaced persons (IDPs) recruited as part of a separate validity study of adapted mental health instruments. We examined internal consistency reliability, test-retest reliability, and construct and criterion validity for each scale on the measure. We randomly assigned half the participants to respond to a vignette depicting existing local psychiatric services which we knew were not well regarded, while the other half was randomized to a vignette describing a potentially more well-implemented mental health service. Criterion validity was assessed by comparing scores on each scale by vignette and by overall summary ratings of the programs described in the vignettes. RESULTS: N = 169 participated in the qualitative study and N = 153 participated in the validity study. Qualitative findings suggested the addition of several items to the measure and indicated the importance of addressing professionalism/competency of providers in both the scales and the vignettes. Internal consistency reliabilities ranged from α = 0.85 for feasibility to α = 0.91 for appropriateness. Test-rest reliabilities were acceptable to good for all scales (rho: 0.61-0.79). All scales demonstrated substantial and significant differences in average scores by vignette assignment (ORs: 2.21-5.6) and overall ratings (ORs: 5.1-14.47), supporting criterion validity. CONCLUSIONS: This study represents an innovative mixed-methods approach to testing an implementation science measure in contexts outside the United States. Results support the reliability and validity of most scales for consumers in Ukraine. Challenges included large amounts of missing data due to participants' difficulties responding to questions about a hypothetical program.


Assuntos
Saúde Global , Ciência da Implementação , Serviços de Saúde Mental/organização & administração , Serviços de Saúde Mental/normas , Humanos , Psicometria , Pesquisa Qualitativa , Reprodutibilidade dos Testes , Projetos de Pesquisa , Ucrânia
5.
Pediatr Surg Int ; 34(9): 967-970, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30051148

RESUMO

BACKGROUND: After definitive repair of esophageal atresia (EA) and tracheoesophageal fistula (TEF), a chest tube (CT) may be left in place to diagnose and conservatively treat a postoperative anastomotic leak, although its necessity is controversial. The purpose of this study was to determine if the use of a CT decreases rates of early postoperative complications after EA and TEF repair. METHODS: A retrospective chart review was performed to identify all patients with EA and TEF who underwent repair between 1985 and 2012. Univariate analysis was performed to compare patients who did or did not have a CT in terms of preoperative characteristics and postoperative outcomes. RESULTS: One hundred twenty neonates were included; 69 had a CT inserted intraoperatively, while 51 did not. The two groups were similar in terms of patient characteristics. There was no statistically significant difference between the groups in terms of length of hospital stay (31 ± 12 vs. 36 ± 16 days, p = 0.5), or complication rates (13% vs. 12%, p = 0.9) for those with or without CT, respectively. CONCLUSIONS: The use of a CT does not alter early postoperative complications after EA/TEF repair.


Assuntos
Tubos Torácicos , Atresia Esofágica/cirurgia , Fístula Traqueoesofágica/cirurgia , Fístula Anastomótica/diagnóstico , Fístula Anastomótica/terapia , Feminino , Humanos , Recém-Nascido , Tempo de Internação , Masculino , Ontário , Complicações Pós-Operatórias , Reoperação/estatística & dados numéricos , Estudos Retrospectivos
6.
AIDS Care ; 29(6): 793-799, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27951734

RESUMO

Prior studies indicate a substantial link between maternal depression and early child health but give limited consideration to the direction of this relationship or the context in which it occurs. We sought to create a contextually informed conceptual framework of this relationship through semi-structured interviews with women that had lived experience of caring for an HIV-infected child while coping with depression and anxiety symptoms. Caregivers explained their role in raising healthy children as complex and complicated by poverty, stigma, and isolation. Caregivers discussed the effects of their own mental health on child well-being as primarily emotional and behavioral, and explained how looking after a child could bring distress, particularly when unable to provide desired care for sick children. Our findings suggest the need for investigation of the reciprocal effects of child sickness on caregiver wellness and for integrated programs that holistically address the needs of HIV-affected families.


Assuntos
Ansiedade , Cuidadores/psicologia , Depressão , Infecções por HIV , Saúde Mental , Adaptação Psicológica , Adulto , Ansiedade/etiologia , Pré-Escolar , Depressão/etiologia , Feminino , Infecções por HIV/terapia , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Pobreza , Isolamento Social/psicologia , Estigma Social , Adulto Jovem
7.
Scand J Med Sci Sports ; 27(1): 4-25, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27263489

RESUMO

The applications of Western/immunoblotting (WB) techniques have reached multiple layers of the scientific community and are now considered routine procedures in the field of physiology. This is none more so than in relation to skeletal muscle physiology (i.e., resolving the mechanisms underpinning adaptations to exercise). Indeed, the inclusion of WB data is now considered an essential aspect of many such physiological publications to provide mechanistic insight into regulatory processes. Despite this popularity, and due to the ubiquitous and relatively inexpensive availability of WB equipment, the quality of WB in publications and subsequent analysis and interpretation of the data can be variable, perhaps resulting in spurious conclusions. This may be due to poor laboratory technique and/or lack of comprehension of the critical steps involved in WB and what quality control procedures should be in place to ensure robust data generation. The present review aims to provide a detailed description and critique of WB procedures and technicalities, from sample collection through preparation, blotting and detection, to analysis of the data collected. We aim to provide the reader with improved expertise to critically conduct, evaluate, and troubleshoot the WB process, to produce reproducible and reliable blots.


Assuntos
Western Blotting/métodos , Músculo Esquelético/metabolismo , Western Blotting/normas , Confiabilidade dos Dados , Humanos , Fisiologia , Manejo de Espécimes/métodos , Manejo de Espécimes/normas
8.
Soc Psychiatry Psychiatr Epidemiol ; 51(7): 981-91, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27083900

RESUMO

PURPOSE: Prevalence estimates of depression vary between countries, possibly due to differential functioning of items between settings. This study compared the performance of the widely used Hopkins symptom checklist 15-item depression scale (HSCL-15) across multiple settings using item response theory analyses. Data came from adult populations in the low and middle income countries (LMIC) of Colombia, Indonesia, Kurdistan Iraq, Rwanda, Iraq, Thailand (Burmese refugees), and Uganda (N = 4732). METHODS: Item parameters based on a graded response model were compared across LMIC settings. Differential item functioning (DIF) by setting was evaluated using multiple indicators multiple causes (MIMIC) models. RESULTS: Most items performed well across settings except items related to suicidal ideation and "loss of sexual interest or pleasure," which had low discrimination parameters (suicide: a = 0.31 in Thailand to a = 2.49 in Indonesia; sexual interest: a = 0.74 in Rwanda to a = 1.26 in one region of Kurdistan). Most items showed some degree of DIF, but DIF only impacted aggregate scale-level scores in Indonesia. CONCLUSIONS: Thirteen of the 15 HSCL depression items performed well across diverse settings, with most items showing a strong relationship to the underlying trait of depression. The results support the cross-cultural applicability of most of these depression symptoms across LMIC settings. DIF impacted aggregate depression scores in one setting illustrating a possible source of measurement invariance in prevalence estimates.


Assuntos
Comparação Transcultural , Depressão/epidemiologia , Países em Desenvolvimento/estatística & dados numéricos , Adulto , Colômbia/epidemiologia , Depressão/etnologia , Etnicidade/psicologia , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Indonésia/epidemiologia , Iraque/epidemiologia , Masculino , Modelos Teóricos , Prevalência , Escalas de Graduação Psiquiátrica , Psicometria , Ruanda/epidemiologia , Tailândia/epidemiologia , Uganda/epidemiologia
9.
Breast Cancer Res Treat ; 154(1): 89-97, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26456573

RESUMO

Amplified PI3K/Akt/mTOR signaling is common in metastatic breast cancer (MBC). The mTOR inhibitor everolimus improves progression-free survival (PFS) when added to steroidal aromatase inhibitor therapy. This randomized phase II trial compares the efficacy of paclitaxel/bevacizumab/everolimus and paclitaxel/bevacizumab/placebo as first-line treatment for MBC. Patients with untreated HER2-negative MBC were randomized (1:1) to receive 28-day cycles of paclitaxel 90 mg/m(2) IV (days 1, 8, and 15) and bevacizumab 10 mg/kg IV (days 1, 15) with either everolimus 10 mg (Arm 1) or placebo (Arm 2) daily. Treatment continued (evaluation every 8 weeks) until progression or unacceptable toxicity. Treatment of 110 patients allowed detection of an improvement in median PFS from 11 to 16 months (70 % power, α = 0.10). Between August 2009 and June 2011, 113 patients (median age 58 years; 88 % ER or PR positive) were randomized (Arm 1, 56; Arm 2, 57). Patients in both arms received a median of six treatment cycles. Median PFS (95 % CI) was 9.1 months (6.8-18.8) for Arm 1, and 7.1 months (5.6-10.8) for Arm 2 (p = 0.89). Comparisons of other efficacy endpoints were also similar in the two treatment arms. Patients receiving everolimus had more anemia, stomatitis, diarrhea, rash, and arthralgia/myalgia, although the overall incidence of severe (grade 3/4) toxicity was similar. The addition of everolimus did not improve the efficacy of weekly paclitaxel/bevacizumab as first-line treatment for patients with HER2-negative MBC. These results contrast with the demonstrated efficacy of adding everolimus to either hormonal or HER2-targeted therapy in previously treated patients.


Assuntos
Bevacizumab/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Everolimo/administração & dosagem , Paclitaxel/administração & dosagem , Adulto , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Receptor ErbB-2/genética
10.
Diabetes Obes Metab ; 17 Suppl 1: 99-105, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26332974

RESUMO

Circadian clocks are biologic oscillators present in all photosensitive species that produce 24-h cycles in the transcription of rate-limiting metabolic enzymes in anticipation of the light-dark cycle. In mammals, the clock drives energetic cycles to maintain physiologic constancy during the daily switch in behavioural (sleep/wake) and nutritional (fasting/feeding) states. A molecular connection between circadian clocks and tissue metabolism was first established with the discovery that 24-h transcriptional rhythms are cell-autonomous and self-sustained in most tissues and comprise a robust temporal network throughout the body. A major window in understanding how the clock is coupled to metabolism was opened with discovery of metabolic syndrome pathologies in multi-tissue circadian mutant mice including susceptibility to diet-induced obesity and diabetes. Using conditional transgenesis and dynamic metabolic testing, we have pinpointed tissue-specific roles of the clock in energy and glucose homeostasis, with our most detailed understanding of this process in endocrine pancreas. Here, we review evidence for dynamic regulation of insulin secretion and oxidative metabolic functions by the clock transcription pathway to regulate homeostatic responses to feeding and fasting. These studies indicate that clock transcription is a determinant of tissue function and provide a reference for understanding molecular pathologies linking circadian desynchrony to metabolic disease.


Assuntos
Relógios Circadianos/fisiologia , Metabolismo Energético , Homeostase , Animais , Ingestão de Alimentos/fisiologia , Jejum/metabolismo , Glucose/metabolismo , Humanos , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Camundongos , Oxirredução , Fotoperíodo , Transdução de Sinais/fisiologia , Transcrição Gênica
11.
Women Birth ; 35(5): e502-e511, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34666952

RESUMO

BACKGROUND: Holistic reflection encompasses reflection as a continuum, incorporating critical reflection, reflexivity, critical thinking and a whole-of-person approach. The development of holistic reflection in midwifery students and midwives is rarely measured in a standardised way. AIM: To develop and test a tool to measure holistic reflection in midwifery students and midwives, for use in pre-registration and post-graduate education, and research. DESIGN: The eight-step approach to tool development by DeVellis was followed with psychometric testing of data from a cross-sectional survey. PARTICIPANTS: Midwifery students (pre-registration and postgraduate), and midwifery alumni of an Australian university. METHODS: Draft items (n = 84) were generated from review of the literature, qualitative research, and a theoretical model. An expert panel (n = 19) reviewed draft items resulting in 39 items. The survey included demographic details, the draft Holistic Reflection Assessment Tool, emotional intelligence subscale, and a social desirability scale. Participants repeated the online survey at two weeks to confirm test-retest reliability. RESULTS: The 187 responses were received. Exploratory factor analysis with varimax rotation revealed three factors accounting for 49% of variance. Internal consistency of the tool was high (α = .91) and test-retest reliability at two weeks (α = .93) demonstrated stability. There were low correlations between social desirability (r = .22, p < .001) and emotional intelligence (r = .21, p < .001) with the new holistic reflection scale. CONCLUSIONS: The Holistic Reflection Assessment Tool is the first for midwifery. The tool was reliable, stable, and valid. Further research is warranted for criterion validity.


Assuntos
Tocologia , Estudantes de Enfermagem , Austrália , Estudos Transversais , Feminino , Humanos , Tocologia/métodos , Gravidez , Psicometria , Reprodutibilidade dos Testes , Estudantes de Enfermagem/psicologia , Inquéritos e Questionários
12.
Vet J ; 280: 105802, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35151883

RESUMO

Traditionally, staphylectomy has been performed using scissors cutting and suturing. Alternative surgical techniques such as staphylectomy with monopolar electrocoagulation, CO2 or diode laser, bipolar vessel sealing device and harmonic shears have also been described. The purpose of this prospective study was to compare the difference in surgical time, intraoperative haemorrhage and histological damage between staphylectomy performed with harmonic shears (HSS), diode laser (DLS) and traditional scissor 'cutting and suturing' technique with Metzenbaum scissors (SIS). Group HSS included 17 dogs, whereas Group DLS and Group SIS included 10 dogs each. Double masked histological evaluation was performed on the excised specimens. The harmonic shears resulted in the shortest surgical times (HSS 46 s, DLS 300 s, SIS 360 s; P < 0.001). There was a difference in the intraoperative haemorrhage among the three techniques; intraoperative haemorrhage did not occur in HSS and DLS groups. HSS was associated with more frequent damage involving the connective tissue (P = 0.001), muscle (P = 0.038), salivary gland tissue (P < 0.001), but less oedema was observed (P < 0.001). HSS was the fastest of the techniques evaluated for caudal elongated soft palate resection, resulting in less tissue oedema, and no intra-operative haemorrhage. These characteristics might result in reduced postoperative swelling and airway obstruction compared to other techniques.


Assuntos
Obstrução das Vias Respiratórias , Doenças do Cão , Obstrução das Vias Respiratórias/patologia , Obstrução das Vias Respiratórias/cirurgia , Obstrução das Vias Respiratórias/veterinária , Animais , Doenças do Cão/patologia , Doenças do Cão/cirurgia , Cães , Lasers Semicondutores/uso terapêutico , Palato Mole/patologia , Palato Mole/cirurgia , Estudos Prospectivos , Resultado do Tratamento
13.
Glob Ment Health (Camb) ; 9: 499-507, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36618735

RESUMO

Background: Integrating services for depression into primary care is key to reducing the treatment gap in low- and middle-income countries. We examined the value of providing the Healthy Activity Programme (HAP), a behavioral activation psychological intervention, within services for depression delivered by primary care workers in Chitwan, Nepal using data from the Programme for Improving Mental Health Care. Methods: People diagnosed with depression were randomized to receive either standard treatment (ST), comprised of psychoeducation, antidepressant medication, and home-based follow up, or standard treatment plus psychological intervention (T + P). We estimated incremental costs and health effects of T + P compared to ST, with quality adjusted life years (QALYs) and depression symptom scores over 12 months as health effects. Nonparametric uncertainty analysis provided confidence intervals around each incremental effectiveness ratio (ICER); results are presented in 2020 international dollars. Results: Sixty participants received ST and 60 received T + P. Implementation costs (ST = $329, T + P = $617) were substantially higher than service delivery costs (ST = $18.7, T + P = $22.4) per participant. ST and T + P participants accrued 46.5 and 49.4 QALYs, respectively. The ICERs for T + P relative to ST were $4422 per QALY gained (95% confidence interval: $2484 to $9550) - slightly above the highly cost-effective threshold - and -$53.21 (95% confidence interval: -$105.8 to -$30.2) per unit change on the Patient Health Questionnaire. Conclusion: Providing HAP within integrated depression services in Chitwan was cost-effective, if not highly cost-effective. Efforts to scale up integrated services in Nepal and similar contexts should consider including evidence-based psychological interventions as a part of cost-effective mental healthcare for depression.

14.
J Chem Phys ; 135(12): 121101, 2011 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-21974504

RESUMO

The band structure and optical absorption spectrum of lithium peroxide (Li(2)O(2)) is calculated from first-principles using the G(0)W(0) approximation and the Bethe-Salpeter equation, respectively. A strongly localized (Frenkel type) exciton corresponding to the π(∗)→σ(∗) transition on the O(2)(-2) peroxide ion gives rise to a narrow absorption peak around 1.2 eV below the calculated bandgap of 4.8 eV. In the excited state, the internal O(2)(-2) bond is significantly weakened due to the population of the σ(∗) orbital. As a consequence, the bond is elongated by almost 0.5 Å leading to an extreme Stokes shift of 2.6 eV. The strong vibronic coupling entails significant broadening of the excitonic absorption peak in good agreement with diffuse reflectance data on Li(2)O(2) which shows a rather featureless spectrum with an absorption onset around 3.0 eV. These results should be important for understanding the origin of the high potential losses and low current densities, which are presently limiting the performance of Li-air batteries.

15.
Clin Nutr ; 40(6): 4456-4464, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33487503

RESUMO

BACKGROUND & AIMS: Nutritional composition is key for skeletal muscle maintenance into older age. Yet the acute effects of collagen protein blended with other protein sources, in relation to skeletal muscle anabolism, are ill-defined. We investigated human muscle protein synthesis (MPS) responses to a 20 g blend of collagen protein hydrolysate + milk protein (CP+MP, 125 ml) oral nutritional supplement (ONS) vs. 20 g non-blended milk protein source (MP, 200 ml) ONS, in older adults. METHODS: Healthy older men (N = 8, 71±1 y, BMI: 27±1 kg·m-2) underwent a randomized trial of 20 g protein, from either a CP+MP blend (Fresubin®3.2 kcal DRINK), or a kcal-matched (higher in essential amino acids (EAA) ONS of MP alone. Vastus lateralis (VL) MPS and plasma AA were determined using stable isotope-tracer mass spectrometry; anabolic signaling was quantified via immuno-blotting in VL biopsies taken at baseline and 2/4 h after ONS feeding. Plasma insulin was measured via enzyme-linked immunosorbent assay (ELISA). Measures were taken at rest, after the feed (FED) and after the feed + exercise (FED-EX) conditions (unilateral leg exercise, 6 × 8, 75% 1-RM). RESULTS: MP resulted in a greater increase in plasma leucine (MP mean: 152 ± 6 µM, CP+MP mean: 113 ± 4 µM (Feed P < 0.001) and EAA (MP mean: 917 ± 25 µM, CP+MP mean: 786 ± 15 µM (Feed P < 0.01) than CP+MP. CP + MP increased plasma glycine (peak 385 ± 57 µM (P < 0.05)), proline (peak 323 ± 29 µM (P < 0.01)) and non-essential amino acids (NEAA) (peak 1621 ± 107 µM (P < 0.01)) with MP showing no increase. Plasma insulin increased in both trials (CP+MP: 58 ± 10 mU/mL (P < 0.01), MP: 42 ± 6 mU/mL (P < 0.01), with peak insulin greater with CP+MP vs. MP (P < 0.01). MPS demonstrated equivalent increases in response to CP+MP and MP under both FED (MP: 0.039 ± 0.005%/h to 0.081 ± 0.014%/h (P < 0.05), CP+MP: 0.042 ± 0.004%/h to 0.085 ± 0.007%/h (P < 0.05)) and FED-EX (MP: 0.039 ± 0.005%/h to 0.093 ± 0.013%/h (P < 0.01), CP+MP: 0.042 ± 0.004%/h to 0.105 ± 0.015%/h, (P < 0.01)) conditions. FED muscle p-mTOR fold-change from baseline increased to a greater extent with CP+MP vs. MP (P < 0.05), whilst FED-EX muscle p-eEF2 fold-change from baseline decreased to a greater extent with CP+MP vs. MP (P < 0.05); otherwise anabolic signaling responses were indistinguishable. CONCLUSION: Fresubin®3.2 kcal DRINK, which contains a 20 g mixed blend of CP+MP, resulted in equivalent MPS responses to MP alone. Fresubin® 3.2 Kcal DRINK may provide a suitable alternative to MP for use in older adults and a convenient way to supplement calories and protein to improve patient adherence and mitigate muscle mass loss.


Assuntos
Aminoácidos Essenciais/análise , Colágeno , Suplementos Nutricionais , Alimentos Formulados , Proteínas do Leite , Proteínas Musculares/biossíntese , Hidrolisados de Proteína , Idoso , Aminoácidos/sangue , Estudos Cross-Over , Alimentos Formulados/análise , Humanos , Insulina/sangue , Masculino , Proteínas do Leite/análise , Músculo Esquelético/metabolismo , Transdução de Sinais
16.
Sci Rep ; 11(1): 22481, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34795364

RESUMO

We have performed sound velocity and unit cell volume measurements of three synthetic, ultrafine micro/nanocrystalline grossular samples up to 50 GPa using Brillouin spectroscopy and synchrotron X-ray diffraction. The samples are characterized by average grain sizes of 90 nm, 93 nm and 179 nm (hereinafter referred to as samples Gr90, Gr93, and Gr179, respectively). The experimentally determined sound velocities and elastic properties of Gr179 sample are comparable with previous measurements, but slightly higher than those of Gr90 and Gr93 under ambient conditions. However, the differences diminish with increasing pressure, and the velocity crossover eventually takes place at approximately 20-30 GPa. The X-ray diffraction peaks of the ultrafine micro/nanocrystalline grossular samples significantly broaden between 15-40 GPa, especially for Gr179. The velocity or elasticity crossover observed at pressures over 30 GPa might be explained by different grain size reduction and/or inhomogeneous strain within the individual grains for the three grossular samples, which is supported by both the pressure-induced peak broadening observed in the X-ray diffraction experiments and transmission electron microscopy observations. The elastic behavior of ultrafine micro/nanocrystalline silicates, in this case, grossular, is both grain size and pressure dependent.

17.
Clin Nutr ESPEN ; 46: 394-404, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34857226

RESUMO

BACKGROUND & AIMS: The skeletal muscle anabolic effects of n-3 polyunsaturated fatty acids (n-3 PUFA) appear favoured towards women; a property that could be exploited in older women who typically exhibit poor muscle growth responses to resistance exercise training (RET). Here we sought to generate novel insights into the efficacy and mechanisms of n-3 PUFA alongside short-term RET in older women. METHODS: We recruited 16 healthy older women (Placebo n = 8 (PLA): 67±1y, n-3 PUFA n = 8: 64±1y) to a randomised double-blind placebo-controlled trial (n-3 PUFA; 3680 mg/day versus PLA) of 6 weeks fully-supervised progressive unilateral RET (i.e. 6 × 8 reps, 75% 1-RM, 3/wk-1). Strength was assessed by knee extensor 1-RM and isokinetic dynamometry âˆ¼ every 10 d. Thigh fat free mass (TFFM) was measured by DXA at 0/3/6 weeks. Bilateral vastus lateralis (VL) biopsies at 0/2/4/6 weeks with deuterium oxide (D2O) dosing were used to determine MPS responses for 0-2 and 4-6 weeks. Further, fibre cross sectional area (CSA), myonuclei number and satellite cell (SC) number were assessed, alongside muscle anabolic/catabolic signalling via immunoblotting. RESULTS: RET increased 1-RM equally in the trained leg of both groups (+23 ± 5% n-3 PUFA vs. +25 ± 5% PLA (both P < 0.01)) with no significant increase in maximum voluntary contraction (MVC) (+10 ± 6% n-3 PUFA vs. +13 ± 5% PLA). Only the n-3 PUFA group increased TFFM (3774 ± 158 g to 3961 ± 151 g n-3 PUFA (P < 0.05) vs. 3406 ± 201 g to 3561 ± 170 PLA) and type II fibre CSA (3097 ± 339 µm2 to 4329 ± 264 µm2 n-3 PUFA (P < 0.05) vs. 2520 ± 316 µm2 to 3467 ± 303 µm2 in PL) with RET. Myonuclei number increased equally in n-3 PUFA and PLA in both type I and type II fibres, with no change in SC number. N-3 PUFA had no added benefit on muscle protein synthesis (MPS), however, during weeks 4-6 of RET, absolute synthesis rates (ASR) displayed a trend to increase with n-3 PUFA only (5.6 ± 0.3 g d-1 to 7.1 ± 0.5 g d-1 n-3 PUFA (P = 0.09) vs. 5.5 ± 0.5 g d-1 to 6.5 ± 0.5 g d-1 PLA). Further, the n-3 PUFA group displayed greater 4EBP1 activation after acute RE at 6 weeks. CONCLUSION: n3-PUFA enhanced RET gains in muscle mass through type II fibre hypertrophy, with data suggesting a role for MPS rather than via SC recruitment. As such, the present study adds to a literature base illustrating the apparent enhancement of muscle hypertrophy with RET in older women fed adjuvant n3-PUFA.


Assuntos
Treinamento Resistido , Idoso , Suplementos Nutricionais , Exercício Físico , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas Musculares , Músculo Esquelético
18.
J Exp Med ; 148(3): 776-86, 1978 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29937

RESUMO

The present studies demonstrate that antisera directed against Streptococcus pneumoniae type 14 is opsonic for group B streptococci type III in a neutrophile-mediated bactericidal assay. Specificity was demonstrated by the observations that group B streptococci type III and S. pneumoniae type 14 adsorbed the opsonic activity of anti-S. pneumoniae type 14 antisera. Group B streptococci strain 090R (devoid of type antigens) and S. pneumoniae type 3, did not remove the opsonic activity of anti-S. pneumoniae type 14 serum. In vivo studies using a suckling rat model of neonatal group B streptococcal type III sepsis demonstrated that antisera directed against S. pneumoniae type 14 was highly protective.


Assuntos
Anticorpos Antibacterianos , Infecções Estreptocócicas/terapia , Streptococcus agalactiae/imunologia , Streptococcus pneumoniae/imunologia , Animais , Especificidade de Anticorpos , Atividade Bactericida do Sangue , Reações Cruzadas , Modelos Animais de Doenças , Imunoterapia , Neutrófilos/imunologia , Proteínas Opsonizantes , Polissacarídeos Bacterianos/imunologia , Ratos
19.
J Urol ; 183(5): 2012-8, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20303527

RESUMO

PURPOSE: Fowler and Stephens showed that by dividing the spermatic vessels a high intra-abdominal testis could be placed in the scrotum. Testicular atrophy is a potential complication of this technique. We conducted a systematic review to determine whether single or 2-stage Fowler-Stephens orchiopexy results in better testicular viability. MATERIALS AND METHODS: We searched electronic databases, clinical trial registries and gray literature. We included reports describing boys younger than 18 years with a primary outcome of "testicular viability and position." We performed a meta-analysis using random effects models. Heterogeneity was assessed using forest plot and I(2) statistic. RESULTS: We identified 1,807 citations and included 61 articles. Single stage Fowler-Stephens orchiopexy was discussed in 9 articles, a 2-stage procedure in 36 and both approaches in 16. There were no randomized controlled trials, and most studies were cohort or case series. The pooled estimate of success rates was 80% for single stage Fowler-Stephens orchiopexy (95% CI 75 to 86) and 85% for 2-stage Fowler-Stephens orchiopexy (95% CI 81 to 90). The pooled odds ratio of single stage vs 2-stage Fowler-Stephens orchiopexy was 2.0 (95% CI 1.1 to 3.9) favoring the 2-stage procedure. There was no difference in the success rate between laparoscopic and open techniques in either single or 2-stage Fowler-Stephens orchiopexy. There was no evidence of asymmetry on the funnel plot. There were no complications reported with single stage, while ileus, hematoma and infection were the most common complications with 2-stage Fowler-Stephens orchiopexy. CONCLUSIONS: Both techniques have a fairly high success rate but 2-stage Fowler-Stephens orchiopexy appears to carry a higher rate of success than the single stage approach (85% vs 80%, OR 2 in favor of 2-stage). Laparoscopic and open techniques had the same success rate. However, the level of evidence of the studies was low, and a study of a more robust design, such as a randomized controlled trial, should be performed.


Assuntos
Orquidopexia , Adolescente , Criança , Criptorquidismo/cirurgia , Humanos , Masculino , Escroto/cirurgia , Testículo/cirurgia
20.
Nature ; 406(6791): 46-8, 2000 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-10894534

RESUMO

The magnetic state of a ferromagnet can affect the electrical transport properties of the material; for example, the relative orientation of the magnetic moments in magnetic multilayers underlies the phenomenon of giant magnetoresistance. The inverse effect--in which a large electrical current density can perturb the magnetic state of a multilayer--has been predicted and observed experimentally with point contacts and lithographically patterned samples. Some of these observations were taken as indirect evidence for current-induced excitation of spin waves, or 'magnons'. Here we probe directly the high-frequency behaviour and partial phase coherence of such current-induced excitations, by externally irradiating a point contact with microwaves. We determine the magnon spectrum and investigate how the magnon frequency and amplitude vary with the exciting current. Our observations support the feasibility of a spin-wave maser' or 'SWASER' (spin-wave amplification by stimulated emission of radiation).

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