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1.
Nano Lett ; 24(23): 6897-6905, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38805366

RESUMO

Aluminum nanocrystals created by catalyst-driven colloidal synthesis support excellent plasmonic properties, due to their high level of elemental purity, monocrystallinity, and controlled size and shape. Reduction in the rate of nanocrystal growth enables the synthesis of highly anisotropic Al nanowires, nanobars, and singly twinned "nanomoustaches". Electron energy loss spectroscopy was used to study the plasmonic properties of these nanocrystals, spanning the broad energy range needed to map their plasmonic modes. The coupling between these nanocrystals and other plasmonic metal nanostructures, specifically Ag nanocubes and Au films of controlled nanoscale thickness, was investigated. Al nanocrystals show excellent long-term stability under atmospheric conditions, providing a practical alternative to coinage metal-based nanowires in assembled nanoscale devices.

2.
J Gen Intern Med ; 37(Suppl 1): 22-32, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35349016

RESUMO

BACKGROUND: Stakeholder engagement helps ensure that research is relevant, clinical innovations are responsive, and healthcare services are patient-centered. OBJECTIVE: Establish and sustain a Veteran engagement board involving older Veterans and caregivers to provide input on aging-related research and clinical demonstration projects. DESIGN AND PARTICIPANTS: The Older Veteran Engagement Team (OVET)-a group of eight Veterans and one caregiver who range in age from 62 to 92-was formed in November 2017 and has met monthly since January 2018. The OVET provides feedback on topics that reflect the foci of the VA Eastern Colorado Geriatric Research Education and Clinical Center (GRECC) (e.g., physical functioning, hearing health, and emotional wellness/mental health). Ongoing evaluation documents the return on investment of Veteran engagement. MAIN MEASURES: The OVET member and provider/investigator meeting evaluations with longitudinal follow-up at 6 and 12 months. RESULTS: Return on investment of Veteran engagement is multi-faceted. For OVET, ROI ranges from grant support to improved healthcare quality/efficiency to social-emotional benefits. To date, funding awards total over $2.3 M for NIH and VA-funded projects to which OVET provided substantive feedback. Documented impacts on healthcare services include reductions in patient wait times, more appropriate utilization of services and increased patient satisfaction. Social-emotional benefits include generativity, as OVET members contribute to improving clinical and community-based supports for other Veterans. The OVET provides an opportunity for older Veterans to share their lived experience with trainees and early career investigators who are preparing for careers serving Veterans. CONCLUSION: The OVET is similar to other established stakeholder engagement groups; team members offer their individual viewpoints at any stage of research, clinical demonstration, or quality improvement projects. The OVET provides a mechanism for the voice of older Veterans and caregivers to shape aspects of individual projects. Importantly, these projects support patient-centered care and promote the characteristics of an age-friendly healthcare system.


Assuntos
Veteranos , Idoso , Humanos , Saúde Mental , Satisfação do Paciente , Assistência Centrada no Paciente , Estados Unidos , United States Department of Veterans Affairs
3.
Philos Trans A Math Phys Eng Sci ; 377(2154): 20180407, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31378179

RESUMO

Recent observations of Jupiter's Great Red Spot indicate that the thermosphere above the storm is hotter than its surroundings by more than 700 K. Possible suggested sources for this heating have thus far included atmospheric gravity waves and lightning-driven acoustic waves. Here, we propose that Joule heating, driven by Great Red Spot vorticity penetrating up into the lower stratosphere and coupling to the thermosphere, may contribute to the large observed temperatures. The strength of Joule heating will depend on the local inclination angle of the magnetic field and thus the observed emissions and inferred temperatures should vary with planetary longitude as the Great Red Spot tracks across the planet. This article is part of a discussion meeting issue 'Advances in hydrogen molecular ions: H3+, H5+ and beyond'.

4.
J Chem Phys ; 150(9): 094103, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30849904

RESUMO

From the inception of nuclear magnetic resonance as a spectroscopic technique, the local origin of chemical shifts has been a topic of discussion. A useful concept employed to describe it has been that of the "Lorentz sphere," the approximately spherical volume surrounding a given nucleus in which the electronic currents contribute significantly to the chemical shift, whereas the outside can be considered as an uniformly magnetised "bulk." In this paper, we use the output of the plane wave density functional theory code CASTEP to get a quantitative estimate of the Lorentz sphere in periodic systems. We outline a mathematical description of a radial buildup function for the magnetic shielding starting from the electronic currents and the simple assumption of periodicity. We provide an approximate upper bound for the Lorentz sphere's size in any crystal, then compute buildup functions for a number of sites in two molecular crystals, showing how various chemical features such as hydrogen bonds influence to convergence to the final shielding value.

5.
J Oral Rehabil ; 45(3): 250-257, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29171914

RESUMO

The removal of mandibular third molar teeth is one of the most common oral surgical procedures. In a significant number of patients, it carries a degree of associated morbidity, including damage to the inferior alveolar nerve (IAN). For this reason, practitioners desire the most up-to-date guidance on the most appropriate technique, informed by the best available evidence that will produce the lowest incidence of iatrogenic complications. The aim of this study was to perform a systematic review comparing the effect of coronectomy vs complete surgical extraction of mandibular third molar teeth on the risk of IAN injury and other complications in adults. Studies were identified through Embase (1980-2016) and Ovid MEDLINE (1946-2016) database searches. Search terms included coronectomy, partial root removal, deliberate vital root retention, odontectomy, surgical removal, surgical extraction, complete tooth extraction and extract. Limits of the study included humans, English language and randomised controlled trials (RCTs). Only RCTs comparing IAN damage associated with surgical extraction of mandibular third molars vs coronectomy were included. From our database searches, we identified two unique RCTs matching the inclusion criteria. Both evaluated patients who had specific radiographic signs of intimate relationships with the IAN. Upon detailed analysis, the studies were noted to exhibit a high risk of bias in many categories, thereby rendering their results inconclusive. Although evidence from two RCTs suggests that coronectomy can reduce the risk of IAN injury compared to surgical removal of high-risk mandibular third molars, the quality of evidence is insufficient to provide definitive conclusions regarding the preferred technique.


Assuntos
Nervo Mandibular/cirurgia , Extração Dentária/métodos , Dente Impactado/cirurgia , Traumatismos do Nervo Trigêmeo/prevenção & controle , Humanos , Nervo Mandibular/fisiopatologia , Dente Serotino , Ensaios Clínicos Controlados Aleatórios como Assunto , Irrigação Terapêutica , Técnicas de Fechamento de Ferimentos
6.
Mol Psychiatry ; 21(2): 205-15, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25869802

RESUMO

Prepulse inhibition (PPI) is an example of sensorimotor gating and deficits in PPI have been demonstrated in schizophrenia patients. Phencyclidine (PCP) suppression of PPI in animals has been studied to elucidate the pathological elements of schizophrenia. However, the molecular mechanisms underlying PCP treatment or PPI in the brain are still poorly understood. In this study, quantitative phosphoproteomic analysis was performed on the prefrontal cortex from rats that were subjected to PPI after being systemically injected with PCP or saline. PCP downregulated phosphorylation events were significantly enriched in proteins associated with long-term potentiation (LTP). Importantly, this data set identifies functionally novel phosphorylation sites on known LTP-associated signaling molecules. In addition, mutagenesis of a significantly altered phosphorylation site on xCT (SLC7A11), the light chain of system xc-, the cystine/glutamate antiporter, suggests that PCP also regulates the activity of this protein. Finally, new insights were also derived on PPI signaling independent of PCP treatment. This is the first quantitative phosphorylation proteomic analysis providing new molecular insights into sensorimotor gating.


Assuntos
Fenciclidina/uso terapêutico , Córtex Pré-Frontal/metabolismo , Inibição Pré-Pulso/efeitos dos fármacos , Estimulação Acústica , Animais , Modelos Animais de Doenças , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Fosforilação , Ratos , Ratos Sprague-Dawley , Reflexo de Sobressalto/efeitos dos fármacos , Esquizofrenia/metabolismo , Filtro Sensorial/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
7.
Scand J Med Sci Sports ; 27(11): 1202-1212, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27624363

RESUMO

This study aimed to determine if ice slurry ingestion improved self-paced intermittent exercise in the heat. After a familiarisation session, 12 moderately trained males (30.4 ± 3.4 year, 1.8 ± 0.1 cm, 73.5 ± 14.3 kg, V˙O2max 58.5 ± 8.1 mL/kg/min) completed two separate 31 min self-paced intermittent protocols on a non-motorised treadmill in 30.9 ± 0.9 °C, 41.1 ± 4.0% RH. Thirty minutes prior to exercise, participants consumed either 7.5 g/kg ice slurry (0.1 ± 0.1 °C) (ICE) or 7.5 g/kg water (23.4 ± 0.9 °C) (CONTROL). Despite reductions in Tc (ΔTc : -0.51 ± 0.3 °C, P < 0.05) and thermal sensation prior to exercise, ICE did not enhance self-paced intermittent exercise compared to CONTROL. The average speed during the walk (CONTROL: 5.90 ± 1.0 km, ICE: 5.90 ± 1.0 km), jog (CONTROL: 8.89 ± 1.7 km, ICE: 9.11 ± 1.5 km), run (CONTROL: 12.15 ± 1.7 km, ICE: 12.54 ± 1.5 km) and sprint (CONTROL: 17.32 ± 1.3 km, ICE: 17.18 ± 1.4 km) was similar between conditions (P > 0.05). Mean Tsk , Tb , blood lactate, heart rate and RPE were similar between conditions (P > 0.05). The findings suggest that lowering Tc prior to self-paced intermittent exercise does not translate into an improved performance.


Assuntos
Desempenho Atlético/fisiologia , Ingestão de Alimentos , Exercício Físico/fisiologia , Temperatura Alta , Gelo , Adulto , Temperatura Corporal , Ingestão de Líquidos , Teste de Esforço , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Corrida/fisiologia , Sensação Térmica
8.
Skin Res Technol ; 23(1): 21-29, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27273806

RESUMO

BACKGROUND: Accurate skin colour measurements are important for numerous medical applications including the diagnosis and treatment of cutaneous disorders and the provision of maxillofacial soft tissue prostheses. METHODS: In this study, we obtained accurate skin colour measurements from four different ethnic groups (Caucasian, Chinese, Kurdish, Thai) and at four different body locations (Forehead, cheek, inner arm, back of hand) with a view of establishing a new skin colour database for medical and cosmetic applications. Skin colours are measured using a spectrophotometer and converted to a device-independent standard colour appearance space (CIELAB) where skin colour is expressed as values along the three dimensions: Lightness L*, Redness a* and Yellowness b*. Skin colour differences and variation are then evaluated as a function of ethnicity and body location. RESULTS: We report three main results: (1) When plotted in a standard colour appearance space (CIELAB), skin colour distributions for the four ethnic groups overlap significantly, although there are systematic mean differences. Between ethnicities, the most significant skin colour differences occur along the yellowness dimension, with Thai skin exhibiting the highest yellowness (b*) value and Caucasian skin the lowest value. Facial redness (a*) is invariant across the four ethnic groups. (2) Between different body locations, there are significant variations in redness (a*), with the forehead showing the highest redness value and the inner arm the lowest. (3) The colour gamut is smallest in the Chinese sample and largest in the Caucasian sample, with the Chinese gamut lying entirely the Caucasian gamut. Similarly, the largest variability in skin tones is found in the Caucasian group, and the smallest in the Chinese group. CONCLUSION: Broadly speaking, skin colour variation can be explained by two main factors: individual differences in lightness and yellowness are mostly due to ethnicity, whereas differences in redness are primarily due to different body locations. Variations in lightness are more idiosyncratic probably reflecting the large influence of environmental factors such as exposure to sun.


Assuntos
Colorimetria/normas , Bases de Dados Factuais/normas , Etnicidade , Pigmentação da Pele/fisiologia , Adolescente , Adulto , Idoso , Calibragem/normas , Colorimetria/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
9.
BMC Med Inform Decis Mak ; 17(1): 70, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28558757

RESUMO

BACKGROUND: The tumour stroma -or tumour microenvironment- is an important constituent of solid cancers and it is thought to be one of the main obstacles to quantitative translation of drug activity between the preclinical and clinical phases of drug development. The tumour-stroma relationship has been described as being both pro- and antitumour in multiple studies. However, the causality of this complex biological relationship between the tumour and stroma has not yet been explored in a quantitative manner in complex tumour morphologies. METHODS: To understand how these stromal and microenvironmental factors contribute to tumour physiology and how oxygen distributes within them, we have developed a lattice-based multiscalar cellular automaton model. This model uses principles of cytokine and oxygen diffusion as well as cell motility and plasticity to describe tumour-stroma landscapes. Furthermore, to calibrate the model, we propose an innovative modelling platform to extract model parameters from multiple in-vitro assays. This platform provides a novel way to extract meta-data that can be used to complement in-vivo studies and can be further applied in other contexts. RESULTS: Here we show the necessity of the tumour-stroma opposing relationship for the model simulations to successfully describe the in-vivo stromal patterns of the human lung cancer cell lines Calu3 and Calu6, as models of clinical and preclinical tumour-stromal topologies. This is especially relevant to drugs that target the tumour microenvironment, such as antiangiogenics, compounds targeting the hedgehog pathway or immune checkpoint inhibitors, and is potentially a key platform to understand the mechanistic drivers for these drugs. CONCLUSION: The tumour-stroma automaton model presented here enables the interpretation of complex in-vitro data and uses it to parametrise a model for in-vivo tumour-stromal relationships.


Assuntos
Neoplasias Pulmonares/patologia , Modelos Biológicos , Algoritmos , Calibragem , Linhagem Celular , Proteínas Hedgehog , Humanos , Hipóxia , Imunoquímica , Técnicas In Vitro , Processos Neoplásicos , Oxigênio
10.
Pharmacogenomics J ; 16(4): 326-35, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26503814

RESUMO

Short-acting ß2-agonist bronchodilators are the most common medications used in treating chronic obstructive pulmonary disease (COPD). Genetic variants determining bronchodilator responsiveness (BDR) in COPD have not been identified. We performed a genome-wide association study (GWAS) of BDR in 5789 current or former smokers with COPD in one African-American and four white populations. BDR was defined as the quantitative spirometric response to inhaled ß2-agonists. We combined results in a meta-analysis. In the meta-analysis, single-nucleotide polymorphisms (SNPs) in the genes KCNK1 (P=2.02 × 10(-7)) and KCNJ2 (P=1.79 × 10(-7)) were the top associations with BDR. Among African Americans, SNPs in CDH13 were significantly associated with BDR (P=5.1 × 10(-9)). A nominal association with CDH13 was identified in a gene-based analysis in all subjects. We identified suggestive association with BDR among COPD subjects for variants near two potassium channel genes (KCNK1 and KCNJ2). SNPs in CDH13 were significantly associated with BDR in African Americans.The Pharmacogenomics Journal advance online publication, 27 October 2015; doi:10.1038/tpj.2015.65.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/uso terapêutico , Broncodilatadores/uso terapêutico , Pulmão/efeitos dos fármacos , Variantes Farmacogenômicos/genética , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Negro ou Afro-Americano/genética , Idoso , Caderinas/genética , Europa (Continente) , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Nova Zelândia , América do Norte , Testes Farmacogenômicos , Fenótipo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio de Domínios Poros em Tandem/genética , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Fatores de Risco , Sarcoglicanas/genética , Índice de Gravidade de Doença , Espirometria , Resultado do Tratamento , População Branca/genética
11.
Mol Psychiatry ; 20(3): 361-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24686136

RESUMO

Consistent with recent reports indicating that neurons differentiated in vitro from human-induced pluripotent stem cells (hiPSCs) are immature relative to those in the human brain, gene expression comparisons of our hiPSC-derived neurons to the Allen BrainSpan Atlas indicate that they most resemble fetal brain tissue. This finding suggests that, rather than modeling the late features of schizophrenia (SZ), hiPSC-based models may be better suited for the study of disease predisposition. We now report that a significant fraction of the gene signature of SZ hiPSC-derived neurons is conserved in SZ hiPSC neural progenitor cells (NPCs). We used two independent discovery-based approaches-microarray gene expression and stable isotope labeling by amino acids in cell culture (SILAC) quantitative proteomic mass spectrometry analyses-to identify cellular phenotypes in SZ hiPSC NPCs from four SZ patients. From our findings that SZ hiPSC NPCs show abnormal gene expression and protein levels related to cytoskeletal remodeling and oxidative stress, we predicted, and subsequently observed, aberrant migration and increased oxidative stress in SZ hiPSC NPCs. These reproducible NPC phenotypes were identified through scalable assays that can be applied to expanded cohorts of SZ patients, making them a potentially valuable tool with which to study the developmental mechanisms contributing to SZ.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Neurais/metabolismo , Células-Tronco Pluripotentes/fisiologia , Prosencéfalo/patologia , Esquizofrenia/patologia , Adulto , Animais , Antipsicóticos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Movimento Celular , Células Cultivadas , Feminino , Expressão Gênica/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Moléculas de Adesão de Célula Nervosa/genética , Moléculas de Adesão de Célula Nervosa/metabolismo , Células-Tronco Neurais/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Fenótipo , Células-Tronco Pluripotentes/efeitos dos fármacos , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem
12.
Nature ; 467(7311): 64-7, 2010 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-20811453

RESUMO

The detection of circumstellar water vapour around the ageing carbon star IRC +10216 challenged the current understanding of chemistry in old stars, because water was predicted to be almost absent in carbon-rich stars. Several explanations for the water were postulated, including the vaporization of icy bodies (comets or dwarf planets) in orbit around the star, grain surface reactions, and photochemistry in the outer circumstellar envelope. With a single water line detected so far from this one carbon-rich evolved star, it is difficult to discriminate between the different mechanisms proposed. Here we report the detection of dozens of water vapour lines in the far-infrared and sub-millimetre spectrum of IRC +10216 using the Herschel satellite. This includes some high-excitation lines with energies corresponding to approximately 1,000 K, which can be explained only if water is present in the warm inner sooty region of the envelope. A plausible explanation for the warm water appears to be the penetration of ultraviolet photons deep into a clumpy circumstellar envelope. This mechanism also triggers the formation of other molecules, such as ammonia, whose observed abundances are much higher than hitherto predicted.

13.
Risk Anal ; 36(1): 83-97, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25988341

RESUMO

This article has two aims. The first is to present results that partly explain why some automobile drivers choose to use their seatbelts only part time, thereby exposing themselves to unnecessary risk. The second is to offer and illustrate the "cardinal decision issue perspective"((1)) as a tool for guiding research and development efforts that focus on complex real-life decision behaviors that can entail wide varieties of risk, including but not limited to inconsistent seatbelt use. Each of 24 young male participants drove an instrumented vehicle equipped to record continuously seatbelt use as well as other driving data. After all trips were finished, each participant completed an interview designed to reconstruct how he made randomly selected seatbelt-use decisions under specified conditions. The interview also examined whether and how drivers established "decision policies" regarding seatbelt use. Such policies were good predictors of inconsistent seatbelt use. Drivers who had previously adopted policies calling for consistent seatbelt use were significantly more likely than others to actually drive belted. Meta-decisions about seatbelt policy adoption appeared to rest on factors such as whether the driver had ever been asked to consider selecting a policy. Whether a driver made an ad hoc, on-the-spot seatbelt-use decision was associated with a perceived need to make such a decision. Finally, participants with full-time policies were especially likely to deploy their seatbelts by default, without recognizing the need to decide about belt use on a trip-by-trip basis. We end with recommendations for reducing inconsistencies in seatbelt use in actual practice.

14.
Psychol Med ; 45(11): 2321-31, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25827976

RESUMO

BACKGROUND: Tuberous sclerosis complex (TSC) is associated with intellectual disability, but the risk pathways are poorly understood. METHOD: The Tuberous Sclerosis 2000 Study is a prospective longitudinal study of the natural history of TSC. One hundred and twenty-five UK children age 0-16 years with TSC and born between January 2001 and December 2006 were studied. Intelligence was assessed using standardized measures at ≥2 years of age. The age of onset of epilepsy, the type of seizure disorder, the frequency and duration of seizures, as well as the response to treatment was assessed at interview and by review of medical records. The severity of epilepsy in the early years was estimated using the E-Chess score. Genetic studies identified the mutations and the number of cortical tubers was determined from brain scans. RESULTS: TSC2 mutations were associated with significantly higher cortical tuber count than TSC1 mutations. The extent of brain involvement, as indexed by cortical tuber count, was associated with an earlier age of onset and severity of epilepsy. In turn, the severity of epilepsy was strongly associated with the degree of intellectual impairment. Structural equation modelling supported a causal pathway from genetic abnormality to cortical tuber count to epilepsy severity to intellectual outcome. Infantile spasms and status epilepticus were important contributors to seizure severity. CONCLUSIONS: The findings support the proposition that severe, early onset epilepsy may impair intellectual development in TSC and highlight the potential importance of early, prompt and effective treatment or prevention of epilepsy in tuberous sclerosis.


Assuntos
Epilepsia/diagnóstico , Inteligência , Espasmos Infantis/complicações , Esclerose Tuberosa/genética , Esclerose Tuberosa/psicologia , Adolescente , Criança , Pré-Escolar , Feminino , Testes Genéticos , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Estudos Prospectivos , Fatores de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Reino Unido
15.
Phys Chem Chem Phys ; 17(6): 4250-8, 2015 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-25573603

RESUMO

A selection of carbides (TiC, NbC, TaC, WC and SiC) have been studied using density functional theory. Their calculated adsorption characteristics towards Pt overlayers are presented with a view to the use of the carbides as core-shell components. WC hcp and SiC are observed to support Pt overlayers on all surfaces making them promising candidates for full Pt encapsulation. Pt adsorption on fcc (111) carbide surfaces is observed to take place with the transition metal surface resonances (TMSRs) playing a key role whilst fcc (100) are universally unfavourable towards Pt adsorption. The effect of the carbide supports on oxygen binding on the Pt overlayer is also considered and discussed in relation to the oxygen reduction reaction (ORR). The oxygen adsorption study revealed several Pt-WC surfaces which exhibit reduced oxygen adsorption energies, suggesting they should promote or maintain ORR activity with respect to nanoparticulate Pt catalysts.

16.
J Econ Entomol ; 108(4): 1795-803, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470321

RESUMO

Cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a common pest of cotton throughout much of the world. In the United States, insecticide applications targeting cotton aphid in cotton are common in the Mid-South, Texas, and California. Cotton aphid population dynamics data were collected from eight insecticide efficacy trials conducted in Lubbock, TX, over a 4-yr period. Among the field populations in the nontreated plots, the instantaneous rate of population growth averaged 0.56 ± 0.608, and the mean population doubling time was 3.97 ± 2.16 d. For calculating economic injury levels (EIL) and thresholds, control costs were set at US$30.50/ha, market prices were evaluated at US$0.88, US$1.33, US$1.77, and US$2.21 kg-lint, and cotton yield potentials were evaluated at 672, 896, and 1,120 kg-lint/ha. The EIL we calculated ranged from 66 to 272 aphids per leaf, and averaged 137 aphids per leaf. Economic thresholds (ET) were calculated based on lead times of 1, 3, 5, and 7 d before EIL occurs. The mean ET across control cost, market price, and yield potential were 110 ± 48, 70 ± 31, 45 ± 19, and 29 ± 13 aphids per leaf at lead times of 1, 3, 5, and 7 d, respectively. Most curative pest management tactics in cotton are implemented within 3 d of determining need, and the ET at 3 d that we calculated (70 ± 31 aphids per leaf) overlaps the current recommended action threshold in Texas and California of 50 aphids per leaf.


Assuntos
Afídeos/fisiologia , Produtos Agrícolas/crescimento & desenvolvimento , Gossypium/crescimento & desenvolvimento , Controle de Insetos/economia , Animais , Produtos Agrícolas/economia , Dinâmica Populacional , Texas
17.
J Oral Rehabil ; 42(10): 786-802, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26059454

RESUMO

The inferior alveolar nerve (IAN) and lingual (LN) are susceptible to iatrogenic surgical damage. Systematically review recent clinical evidence regarding IAN/LN repair methods and to develop updated guidelines for managing injury. Recent publications on IAN/LN microsurgical repair from Medline, Embase and Cochrane Library databases were screened by title/abstract. Main texts were appraised for exclusion criteria: no treatment performed or results provided, poor/lacking procedural description, cohort <3 patients. Of 366 retrieved papers, 27 were suitable for final analysis. Treatment type for injured IANs/LNs depended on injury type, injury timing, neurosensory disturbances and intra-operative findings. Best functional nerve recovery occurred after direct apposition and suturing if nerve ending gaps were <10 mm; larger gaps required nerve grafting (sural/greater auricular nerve). Timing of microneurosurgical repair after injury remains debated. Most authors recommend surgery when neurosensory deficit shows no improvement 90 days post-diagnosis. Nerve transection diagnosed intra-operatively should be repaired in situ; minor nerve injury repair can be delayed. No consensus exists regarding optimal methods and timing for IAN/LN repair. We suggest a schematic guideline for treating IAN/LN injury, based on the most current evidence. We acknowledge that additional RCTs are required to provide definitive confirmation of optimal treatment approaches.


Assuntos
Odontologia Baseada em Evidências , Procedimentos Neurocirúrgicos/métodos , Procedimentos de Cirurgia Plástica/métodos , Traumatismos do Nervo Trigêmeo/cirurgia , Humanos , Nervo Lingual/cirurgia , Traumatismos do Nervo Lingual/cirurgia , Nervo Mandibular/cirurgia , Recuperação de Função Fisiológica/fisiologia , Resultado do Tratamento
18.
J Oral Rehabil ; 42(5): 323-30, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25600826

RESUMO

The combination of bite force and jaw muscle electromyography (EMG) provides an insight into the performance of the stomatognathic system, especially in relation to dynamic movement tasks. Literature has extensively investigated possible methods for normalising EMG data encapsulating many different approaches. However, bite force literature trends towards normalising EMG to a maximal voluntary contraction (MVC), which could be difficult for ageing populations or those with poor dental health or limiting conditions such as temporomandibular disorder. The objectives of this study were to (i) determine whether jaw-closing muscle activity is linearly correlated with incremental submaximal and maximal bite force levels and (ii) assess whether normalising maximal and submaximal muscle activity to that produced when performing a low submaximal bite force (20 N) improves repeatability of EMG values. Thirty healthy adults (15 men, 15 women; mean age 21 ± 1·2 years) had bite force measurements obtained using a custom-made button strain gauge load cell. Masseter and anterior temporalis muscle activities were collected bilaterally using surface EMG sensors whilst participants performed maximal biting and three levels of submaximal biting. Furthermore, a small group (n = 4 females) were retested for reliability purposes. Coefficients of variation and intra-class correlation coefficients showed markedly improved reliability when EMG data were normalised compared to non-normalised. This study shows that jaw muscle EMG may be successfully normalised to a very low bite force. This may open possibilities for comparisons between at-risk sample groups that may otherwise find it difficult to produce maximal bite force values.


Assuntos
Força de Mordida , Eletromiografia/métodos , Músculos da Mastigação/fisiologia , Adolescente , Adulto , Análise do Estresse Dentário , Feminino , Humanos , Masculino , Contração Muscular/fisiologia , Reprodutibilidade dos Testes , Processamento de Sinais Assistido por Computador
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