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1.
Plant Physiol ; 173(2): 1226-1234, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27956489

RESUMO

Recent and rapid evolution of resistance to glyphosate, the most widely used herbicides, in several weed species, including common waterhemp (Amaranthus tuberculatus), poses a serious threat to sustained crop production. We report that glyphosate resistance in A tuberculatus was due to amplification of the 5-enolpyruvylshikimate-3-P synthase (EPSPS) gene, which encodes the molecular target of glyphosate. There was a positive correlation between EPSPS gene copies and its transcript expression. We analyzed the distribution of EPSPS copies in the genome of A tuberculatus using fluorescence in situ hybridization on mitotic metaphase chromosomes and interphase nuclei. Fluorescence in situ hybridization analysis mapped the EPSPS gene to pericentromeric regions of two homologous chromosomes in glyphosate sensitive A tuberculatus In glyphosate-resistant plants, a cluster of EPSPS genes on the pericentromeric region on one pair of homologous chromosomes was detected. Intriguingly, two highly glyphosate-resistant plants harbored an additional chromosome with several EPSPS copies besides the native chromosome pair with EPSPS copies. These results suggest that the initial event of EPSPS gene duplication may have occurred because of unequal recombination mediated by repetitive DNA. Subsequently, gene amplification may have resulted via several other mechanisms, such as chromosomal rearrangements, deletion/insertion, transposon-mediated dispersion, or possibly by interspecific hybridization. This report illustrates the physical mapping of amplified EPSPS copies in A tuberculatus.


Assuntos
3-Fosfoshikimato 1-Carboxiviniltransferase/genética , Amaranthus/efeitos dos fármacos , Glicina/análogos & derivados , Resistência a Herbicidas/genética , Amaranthus/genética , Cromossomos de Plantas , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glicina/administração & dosagem , Glicina/farmacologia , Herbicidas/administração & dosagem , Herbicidas/farmacologia , Kansas , Mapeamento Físico do Cromossomo , Proteínas de Plantas/genética , Glifosato
2.
Langmuir ; 34(33): 9598-9605, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30036477

RESUMO

For electrophoretic deposition (EPD) to achieve its potential as a method for assembling functional semiconductors, it will be necessary to understand both what governs the threshold voltage for deposition and how to reduce that threshold. Herein we demonstrate that postsynthetic modification of the surface chemistry of all-inorganic copper zinc tin sulfide (CZTS) nanocrystals (NCs) enables EPD at voltages of as low as 4 V, which is a 3-fold or greater reduction over previous examples of nonoxide semiconductors. The chemical exchange of the original surfactant-based NC-surface ligands with selenide ions yields essentially bare, highly surface-charged NCs. Thus, both the electrophoretic mobility and electrochemical reactivity of these particles are increased, favoring deposition. In situ imaging of the reactor during deposition provides a quantitative measure of the electric field in the bulk of the reactor, yielding fundamental insight into the reaction mechanism and mass transport in the low-voltage regime. A crossover from mass-transport-limited to reaction-rate-limited EPD is observed. Under the latter conditions, the influence of gravity can result in boundary-layer instabilities that are severely deleterious to the uniformity of the deposited film, despite the gravitational stability of the colloids in the absence of electric fields. This knowledge is applied to deposit thick, uniform, and crack-free films without sintering, from stable, well-dispersed colloidal starting materials.

3.
Psychother Res ; 28(3): 406-422, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-27728998

RESUMO

OBJECTIVE: To investigate the pattern of change in emotional states over a course of emotion-focused therapy using the model of sequential emotional processing as an initial framework for analysis. METHOD: This was a single case study observational design examining 15 sessions of therapy with one client. A qualitative analysis of moment-to-moment shifts in client emotional events was conducted. This conceptualised the interplay between experienced emotions using the sequential emotional processing model as an interpretative framework. The analysis was triangulated by using existing observer-based rating scales and reliability assessed with an independent rater. RESULTS: The sequential emotional processing model was found to be an effective means to explain the sequence of expressed emotional events, although some emotional events and emotion scheme change processes pertaining to this particular case required additional explanation than provided in the original model descriptions. CONCLUSIONS: Observed nuances in this specific case included highlighting triggers to emotional experience and avoidance processes fuelled by anticipatory fear. The observations included a process of change through accessing core feelings of shame, fear, and loneliness and their transformation through the generation of self-compassion and assertive anger. Implications for practice are discussed in terms of case conceptualisation and therapeutic strategy.


Assuntos
Transtorno Depressivo/terapia , Terapia Focada em Emoções/métodos , Avaliação de Processos e Resultados em Cuidados de Saúde/métodos , Adulto , Feminino , Humanos
4.
Nano Lett ; 16(6): 3563-70, 2016 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-27135266

RESUMO

Cesium lead iodide possesses an excellent combination of band gap and absorption coefficient for photovoltaic applications in its perovskite phase. However, this is not its equilibrium structure under ambient conditions. In air, at ambient temperature it rapidly transforms to a nonfunctional, so-called yellow phase. Here we show that chloride doping, particularly at levels near the solubility limit for chloride in a cesium lead iodide host, provides a new approach to stabilizing the functional perovskite phase. In order to achieve high doping levels, we first co-deposit colloidal nanocrystals of pure cesium lead chloride and cesium lead iodide, thereby ensuring nanometer-scale mixing even at compositions that potentially exceed the bulk miscibility of the two phases. The resulting nanocrystal solid is subsequently fused into a polycrystalline thin film by chemically induced, room-temperature sintering. Spectroscopy and X-ray diffraction indicate that the chloride is further dispersed during sintering and a polycrystalline mixed phase is formed. Using density functional theory (DFT) methods in conjunction with nudged elastic band techniques, low-energy pathways for interstitial chlorine diffusion into a majority-iodide lattice were identified, consistent with the facile diffusion and fast halide exchange reactions observed. By comparison to DFT-calculated values (with the PBE exchange-correlation functional), the relative change in band gap and the lattice contraction are shown to be consistent with a Cl/I ratio of a few percent in the mixed phase. At these incorporation levels, the half-life of the functional perovskite phase in a humid atmosphere increases by more than an order of magnitude.

5.
J Nutr ; 146(5): 1109-17, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27075910

RESUMO

BACKGROUND: Recent evidence demonstrates the benefits of integrated agriculture and nutrition programs for children's health and nutrition outcomes. These programs may also improve mothers' nutrition and empowerment outcomes. However, evidence from rigorous evaluations is scarce. OBJECTIVE: We examined impacts of Helen Keller International's 2-y enhanced-homestead food production (E-HFP) program in Burkina Faso on the secondary impact measures of mothers' nutrition and empowerment. METHODS: We used a cluster-randomized controlled trial whereby 55 villages with 1767 mothers of young children were randomly assigned to 3 groups: 1) control, 2) E-HFP with the behavior change communication (BCC) strategy implemented by older women leaders, or 3) E-HFP with BCC implemented by health committee members. Data for the treatment groups were pooled for this analysis because no differences were found between the 2 groups in key mothers' outcomes. We used difference-in-differences (DID) estimates to assess impacts on mothers' dietary intake, diversity, body mass index (BMI; in kg/m(2)), prevalence of underweight (BMI <18.5), and empowerment. RESULTS: The E-HFP program significantly increased mothers' intake of fruit (DID = 15.8 percentage points; P = 0.02) and marginally increased their intake of meat/poultry (DID = 7.5 percentage points; P = 0.08) and dietary diversity (DID = 0.3 points; P = 0.08). The prevalence of underweight was significantly reduced among mothers in treatment compared with control villages by 8.7 percentage points (P < 0.01). Although the changes in BMI did not differ between mothers in treatment and control villages, there was a marginally significant interaction (baseline underweight × change in BMI; P-interaction = 0.07), indicating that underweight mothers had a greater increase in BMI than did mothers who were not underweight. The E-HFP program also positively affected mothers' overall empowerment score (DID = 3.13 points out of 37 possible points; P < 0.01) and 3 components of empowerment: meeting with women (DID = 1.21 points out of 5 possible points; P < 0.01), purchasing decisions (DID = 0.86 points out of 8 possible points; P = 0.01), and health care decisions (DID = 0.24 points out of 2 possible points; P = 0.05). CONCLUSIONS: Helen Keller International's E-HFP program in Burkina Faso substantially improved mothers' nutrition and empowerment outcomes. These positive impacts benefit the mothers themselves and may also improve their ability to care for their children. This trial was registered at clinicaltrials.gov as NCT01825226.


Assuntos
Comunicação , Dieta , Comportamento Alimentar , Mães , Poder Psicológico , Avaliação de Programas e Projetos de Saúde , Magreza/dietoterapia , Adulto , Agricultura , Índice de Massa Corporal , Burkina Faso , Humanos , Lactente , Prevalência , Adulto Jovem
6.
J Nutr ; 145(6): 1317-24, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25904734

RESUMO

BACKGROUND: Among young children in Burkina Faso, anemia and chronic and acute undernutrition are widespread. OBJECTIVE: This study assessed the impact of Helen Keller International's (HKI) 2-y integrated agriculture [homestead food production (HFP)] and nutrition and health behavior change communication (BCC) program, targeted to women, on children's (3-12.9 mo old at baseline) anthropometry (stunting, wasting, and underweight), mean hemoglobin (Hb), anemia (Hb < 11 g/dL), and diarrhea prevalence. METHODS: We used a cluster-randomized controlled trial, with 55 villages randomly assigned to a control group (n = 25) or 1 of 2 treatment groups (n = 15 each), which differed by who delivered the BCC messages [older women leaders or health committee (HC) members]. We used difference-in-difference (DID) estimates to assess impacts on child outcomes. RESULTS: We found marginally significant (P < 0.10) impacts on Hb (DID: 0.51 g/dL; P = 0.07) and wasting [DID: -8.8 percentage point (pp); P = 0.08] and statistically significant (P < 0.05) impacts on diarrhea (-15.9 pp; P = 0.00) in HC compared with control villages among children aged 3-12.9 mo and larger impacts for anemia (DID: -14.6 pp; P = 0.03) and mean Hb (DID: 0.74 g/dL; P = 0.03) among younger children (aged 3-5.9 mo). However, we found no significant impacts on stunting or underweight prevalence. Plausibility was supported by greater improvements in women's agricultural production and maternal infant and young child feeding and care knowledge and practices in HC compared with control villages. CONCLUSIONS: HKI's 2-y integrated HFP+BCC program (HC group) significantly improved several child outcomes, including wasting (marginal), diarrhea, Hb, and anemia, especially among the youngest children. This is the first cluster-randomized controlled trial of an HFP program that documents statistically significant positive effects on these child nutrition outcomes. This trial was registered at clinicaltrials.gov as NCT01825226.


Assuntos
Anemia/epidemiologia , Diarreia/epidemiologia , Comportamento Alimentar , Comportamentos Relacionados com a Saúde , Promoção da Saúde/métodos , Magreza/epidemiologia , Anemia/prevenção & controle , Burkina Faso/epidemiologia , Análise por Conglomerados , Diarreia/prevenção & controle , Feminino , Seguimentos , Hemoglobinas/metabolismo , Humanos , Lactente , Fenômenos Fisiológicos da Nutrição do Lactente , Masculino , Estado Nutricional , Prevalência , Magreza/prevenção & controle
7.
Int J Technol Assess Health Care ; 31(4): 223-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26585703

RESUMO

Health systems around the world cope with the challenge of difficult economic times, and the value of health technology assessment (HTA) is increasing. Making the right choices, with limited resources, in the face of increasingly complex technologies requires decisions informed by data and analyses that help us to manage the risks involved. Those who undertake and use HTA can play a greater role in helping decision makers meet these challenges; they need to think how to define innovation and respond to it, how to communicate their analyses, and, critically, how to align their work with the ambitions of their health systems. HTA can become a key health system enabler without compromising its objectivity or independence. It can say that it is too early to determine the value of a new technology when the data simply will not support a safe decision. However, it can also be bold and recommend the managed introduction of new technologies, even when the when the data is immature, provided that the health system understands the risks and there is a plausible case for believing that further research will support the value proposition. The goal for HTA is to be able confidently to do both.


Assuntos
Comunicação , Idioma , Avaliação da Tecnologia Biomédica , Economia
8.
J Dev Stud ; 51(9): 1155-1174, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-30363952

RESUMO

This article uses a mixed-methods approach to analyse the impact of an integrated agriculture and nutrition programme in Burkina Faso on women's and men's assets, and norms regarding ownership, use and control of assets. We use a cluster-randomised controlled trial to determine whether productive asset transfers and increased income-generating opportunities for women increase women's assets over time. Qualitative work on gender norms finds that although men still own and control most assets, women have greater decision-making power and control over home gardens and their produce, and attitudes towards women owning property have become more favourable in treatment areas.

9.
Lancet ; 389(10074): 1102, 2017 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-28322820
10.
Clin Med (Lond) ; 13(1): 13-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23472486

RESUMO

From 1 April 2013, the National Institute for Health and Clinical Excellence (NICE) will be re-established under the provisions of the Health and Social Care Act 2012. Although its name will change to the National Institute for Health and Care Excellence, its acronym--NICE--has been written into the face of the Act. The new NICE will continue to provide the full range of guidance and other products with which the Institute has become associated. It will, though, have enhanced responsibilities in the development of quality standards and in the introduction of value-based pricing. In addition, it will be responsible for producing guidance for social care (hence the change in its name) and associated quality standards. The changes to the structure of NICE will not change its relationship with the professions and we are confident that it will continue to be relevant to all those working in the National Health Service.


Assuntos
Academias e Institutos , Prioridades em Saúde/normas , Programas Nacionais de Saúde/organização & administração , Qualidade da Assistência à Saúde , Medicina Estatal , Humanos , Programas Nacionais de Saúde/normas , Reino Unido
12.
Elife ; 102021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34761751

RESUMO

UCH37, also known as UCHL5, is a highly conserved deubiquitinating enzyme (DUB) that associates with the 26S proteasome. Recently, it was reported that UCH37 activity is stimulated by branched ubiquitin (Ub) chain architectures. To understand how UCH37 achieves its unique debranching specificity, we performed biochemical and Nuclear Magnetic Resonance (NMR) structural analyses and found that UCH37 is activated by contacts with the hydrophobic patches of both distal Ubs that emanate from a branched Ub. In addition, RPN13, which recruits UCH37 to the proteasome, further enhances branched-chain specificity by restricting linear Ub chains from having access to the UCH37 active site. In cultured human cells under conditions of proteolytic stress, we show that substrate clearance by the proteasome is promoted by both binding and deubiquitination of branched polyubiquitin by UCH37. Proteasomes containing UCH37(C88A), which is catalytically inactive, aberrantly retain polyubiquitinated species as well as the RAD23B substrate shuttle factor, suggesting a defect in recycling of the proteasome for the next round of substrate processing. These findings provide a foundation to understand how proteasome degradation of substrates modified by a unique Ub chain architecture is aided by a DUB.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Domínio Catalítico , Deleção de Genes , Células HCT116 , Células HEK293 , Humanos , Corpos de Inclusão , Peptídeos e Proteínas de Sinalização Intracelular/genética , Complexo de Endopeptidases do Proteassoma/genética , Ligação Proteica , Proteólise , Ubiquitina/genética
13.
Econ Hum Biol ; 36: 100820, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31683110

RESUMO

Integrated agricultural-nutrition programs are often implemented under the premise that program effects are durable and spillover. This paper estimates one year post-program effects, three-year aggregate program effects and spillover effects using treated and untreated household cohorts. Two treatment interventions implemented agricultural interventions with behavior change communication strategies varying implementers using either village health committees or older female leaders. In the post-program period, program effects deteriorated relative to program period impacts documented in Olney et al. (2015), but the three-year agricultural, nutrition knowledge, health care practices and severe anemia impacts remained statistically significant. Despite the non-rival nature of nutrition education and promoted production techniques, there is little evidence of agricultural technology or health knowledge spillovers to non-treated households within treatment communities. Spillover effects measured for appropriate treatment of diarrhea (10 pp increase in giving rehydration salts rather than traditional medicine), wasting (20 pp lower probability of wasting) and children's anemia status (7 pp reduction in severe anemia) significantly improve in later cohorts. The aggregate program effects and spillovers are generally robust to multiple hypothesis testing.


Assuntos
Agricultura/métodos , Diarreia , Educação em Saúde/organização & administração , Conhecimentos, Atitudes e Prática em Saúde , Estado Nutricional , Anemia/epidemiologia , Anemia/prevenção & controle , Criança , Transtornos da Nutrição Infantil/epidemiologia , Transtornos da Nutrição Infantil/prevenção & controle , Diarreia/terapia , Feminino , Humanos , Masculino
14.
Lancet ; 381(9876): 1460, 2013 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-23622283
15.
J Phys Chem Lett ; 8(6): 1278-1282, 2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-28256139

RESUMO

The perovskite phase of cesium lead iodide (α-CsPbI3 or "black" phase) possesses favorable optoelectronic properties for photovoltaic applications. However, the stable phase at room temperature is a nonfunctional "yellow" phase (δ-CsPbI3). Black-phase polycrystalline thin films are synthesized above 330 °C and rapidly quenched to room temperature, retaining their phase in a metastable state. Using differential scanning calorimetry, it is shown herein that the metastable state is maintained in the absence of moisture, up to a temperature of 100 °C, and a reversible phase-change enthalpy of 14.2 (±0.5) kJ/mol is observed. The presence of atmospheric moisture hastens the black-to-yellow conversion kinetics without significantly changing the enthalpy of the transition, indicating a catalytic effect, rather than a change in equilibrium due to water adduct formation. These results delineate the conditions for trapping the desired phase and highlight the significant magnitude of the entropic stabilization of this phase.

17.
Health Serv J ; 115(5948): 16-7, 1, 2005 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-15825651

RESUMO

Last week the National Institute for Clinical Excellence merged with the Health Development Agency, boosting the profile of an organisation that chief executive Andrew Dillon claims 'all three parties are keen to maintain' and which 26 per cent of the population has heard of. But is the newly expanded NICE ready--and able--to deliver on its public health remit?


Assuntos
Garantia da Qualidade dos Cuidados de Saúde , Medicina Estatal/organização & administração , Financiamento de Capital , Instituições Associadas de Saúde , Administração em Saúde Pública/economia , Medicina Estatal/normas , Reino Unido
20.
Nanotoxicology ; 7(1): 21-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22047053

RESUMO

One primary challenge in nanotoxicology studies is the lack of well-characterised nanoparticle reference materials which could be used as positive or negative nanoparticle controls. The National Institute of Standards and Technology (NIST) has developed three gold nanoparticle (AuNP) reference materials (10, 30 and 60 nm). The genotoxicity of these nanoparticles was tested using HepG2 cells and calf-thymus DNA. DNA damage was assessed based on the specific and sensitive measurement of four oxidatively-modified DNA lesions (8-hydroxy-2´-deoxyguanosine, 8-hydroxy-2´-deoxyadenosine, (5´S)-8,5´-cyclo-2´-deoxyadenosine and (5´R)-8,5´-cyclo-2´-deoxyadenosine) using liquid chromatography/tandem mass spectrometry. Significantly elevated, dose-dependent DNA damage was not detected at concentrations up to 0.2 µg/ml, and free radicals were not detected using electron paramagnetic resonance spectroscopy. These data suggest that the NIST AuNPs could potentially serve as suitable negative-control nanoparticle reference materials for in vitro and in vivo genotoxicity studies. NIST AuNPs thus hold substantial promise for improving the reproducibility and reliability of nanoparticle genotoxicity studies.


Assuntos
Ouro/química , Nanopartículas Metálicas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Animais , Linhagem Celular , Cromatografia Líquida , Dano ao DNA , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Microscopia Eletrônica de Transmissão , Espectrometria de Massas em Tandem
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