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1.
New Phytol ; 229(2): 783-790, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32813888

RESUMO

From global food security to textile production and biofuels, the demands currently made on plant photosynthetic productivity will continue to increase. Enhancing photosynthesis using designer, green and sustainable materials offers an attractive alternative to current genetic-based strategies and promising work with nanomaterials has recently started to emerge. Here we describe the in planta use of carbon-based nanoparticles produced by low-cost renewable routes that are bioavailable to mature plants. Uptake of these functionalised nanoparticles directly from the soil improves photosynthesis and also increases crop production. We show for the first time that glucose functionalisation enhances nanoparticle uptake, photoprotection and pigment production, unlocking enhanced yields. This was demonstrated in Triticum aestivum 'Apogee' (dwarf bread wheat) and resulted in an 18% increase in grain yield. This establishes the viability of a functional nanomaterial to augment photosynthesis as a route to increased crop productivity.


Assuntos
Carbono , Glucose , Produção Agrícola , Fotossíntese , Triticum
2.
Pain Physician ; 19(1): E113-20, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26752479

RESUMO

BACKGROUND: Appropriate treatment choice for osteoporotic vertebral compression fractures (OVCF) is challenging due to patient heterogeneity. Using the RAND/UCLA method, an international multidisciplinary expert panel established patient-specific criteria for the choice between non-surgical management (NSM), vertebroplasty (VP), and balloon kyphoplasty (BKP). OBJECTIVES: To assess the applicability of the appropriateness criteria in real-life practice. STUDY DESIGN: Prospective observational study. SETTING: Eight practices of experts who participated in the panel study, including 2 interventional radiologists, one internal medicine specialist, 2 neurosurgeons, and 3 orthopedic/trauma surgeons. Practices were located in Belgium, Germany, Italy, Switzerland, and the United Kingdom. METHODS: Using an online data capture program, participants documented the clinical profile (age, gender, previous VCFs, time since fracture, magnetic resonance imaging (MRI) findings, evolution of symptoms, impact of symptoms on quality of life, spinal deformity, ongoing fracture process, and presence of pulmonary dysfunction) and treatment choice for consecutive patients who consulted them for OVCF. RESULTS: In total 426 patients were included. BKP was the most frequently chosen treatment option (49%), followed by VP (34%) and NSM (14%). When compared with the panel recommendations, inappropriate treatment choices were rare (5% for NSM, 2% for VP, none for BKP). Treatment choice was strongly associated with the clinical variables used in the panel study. Differences in treatment decisions between interventional radiologists and surgeons were largely determined by differences in patient characteristics, with time of clinical presentation being the dominant factor. LIMITATION: The study population was restricted to the practices of the participants of the panel study. CONCLUSION: This international, multi-specialty utilization review showed excellent applicability of, and good adherence with RAND/UCLA-based recommendations on treatment choice in OVCF.


Assuntos
Fraturas por Compressão/diagnóstico , Fraturas por Compressão/terapia , Osteoporose/diagnóstico , Osteoporose/terapia , Fraturas da Coluna Vertebral/diagnóstico , Fraturas da Coluna Vertebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fraturas por Compressão/epidemiologia , Alemanha , Humanos , Internacionalidade , Cifoplastia/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Estudos Prospectivos , Qualidade de Vida , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/cirurgia , Resultado do Tratamento , Reino Unido , Vertebroplastia/métodos
3.
Arthroscopy ; 19(1): 50-3, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12522402

RESUMO

PURPOSE: The study goal was to assess the efficacy of pre-emptive analgesia in a clinical setting. TYPE OF STUDY: A block randomized, double-blind design was used. METHODS: Subjects were 40 patients undergoing day-case arthroscopy of the knee. The trial group received a prophylactic injection of bupivacaine with adrenaline. After surgery, a placebo injection was given. The postsurgical injection group received identical injections in reverse order. There was no difference in the mean dose of propofol used to maintain general anesthesia between groups: 15 mg/kg/h (standard deviation [SD] = 2.85) trial versus 14.6 mg/kg/h (SD = 1.96) postsurgical injection (95% confidence interval [CI] = -1.14 to 1.94). RESULTS: Although no statistically significant difference was observed in postoperative pain scores at 15, 30, or 60 minutes, there was a trend for the trial group to require less analgesia in recovery (chi2 = 9.74; P =.1). CONCLUSIONS: Prophylactic local anesthesia confers no statistically significant reduction in pain scores or perioperative general anesthetic requirements as compared with postoperative administration. The pre-emptive effect in clinical practice may be less dramatic than that observed in more controlled animal models. Further studies are required to investigate the magnitude of the pre-emptive effect in clinical practice.


Assuntos
Anestesia Local/métodos , Artroscopia/métodos , Joelho/cirurgia , Dor Pós-Operatória/prevenção & controle , Adulto , Idoso , Bupivacaína/administração & dosagem , Bupivacaína/uso terapêutico , Método Duplo-Cego , Esquema de Medicação , Combinação de Medicamentos , Epinefrina/administração & dosagem , Epinefrina/uso terapêutico , Feminino , Humanos , Injeções Intra-Articulares , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Cuidados Pós-Operatórios/métodos , Cuidados Pré-Operatórios/métodos
4.
PLoS One ; 9(3): e91683, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24670971

RESUMO

The explosion of the Deepwater Horizon drilling platform created the largest marine oil spill in U.S. history. As part of the Natural Resource Damage Assessment process, we applied an innovative modeling approach to obtain upper estimates for occupancy and for number of manatees in areas potentially affected by the oil spill. Our data consisted of aerial survey counts in waters of the Florida Panhandle, Alabama and Mississippi. Our method, which uses a Bayesian approach, allows for the propagation of uncertainty associated with estimates from empirical data and from the published literature. We illustrate that it is possible to derive estimates of occupancy rate and upper estimates of the number of manatees present at the time of sampling, even when no manatees were observed in our sampled plots during surveys. We estimated that fewer than 2.4% of potentially affected manatee habitat in our Florida study area may have been occupied by manatees. The upper estimate for the number of manatees present in potentially impacted areas (within our study area) was estimated with our model to be 74 (95%CI 46 to 107). This upper estimate for the number of manatees was conditioned on the upper 95%CI value of the occupancy rate. In other words, based on our estimates, it is highly probable that there were 107 or fewer manatees in our study area during the time of our surveys. Because our analyses apply to habitats considered likely manatee habitats, our inference is restricted to these sites and to the time frame of our surveys. Given that manatees may be hard to see during aerial surveys, it was important to account for imperfect detection. The approach that we described can be useful for determining the best allocation of resources for monitoring and conservation.


Assuntos
Ecossistema , Monitoramento Ambiental , Poluição por Petróleo , Trichechus/fisiologia , Alabama , Animais , Florida , Geografia , Mississippi , Inquéritos e Questionários
5.
Pain Physician ; 16(5): E519-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24077202

RESUMO

BACKGROUND: The heterogeneity of patients with osteoporotic vertebral compression fractures (VCF) necessitates a tailored approach of balancing the benefits and limitations of available treatments. Current guidelines are divergent, sometimes contradictory, and often insufficiently detailed to guide practice decisions. OBJECTIVES: This study aimed at establishing treatment recommendations at the patient-specific level. STUDY DESIGN: Using the RAND/UCLA Appropriateness Method (RAM), the appropriateness of different treatment options for osteoporotic VCFs was assessed. SETTING: The assessment was conducted by a European multidisciplinary panel of 12 experts. METHODS: The appropriateness of non-surgical management (NSM), vertebroplasty (VP), and balloon kyphoplasty (BKP) was determined for 128 hypothetical patient profiles. These were unique combinations of clinical factors considered relevant to treatment choice (time since fracture, MRI findings, impact and evolution of symptoms, spinal deformity, ongoing fracture process, and pulmonary dysfunction). After 2 individual rating rounds and plenary meetings, appropriateness statements (appropriate, inappropriate, and uncertain) were calculated for all clinical scenarios. RESULTS: Disagreement dropped from 31% in the first round to 7% in the second round. Appropriateness outcomes showed specific patterns for the 3 treatments. For three-quarters of the profiles, only one treatment was considered appropriate: NSM 25%, VP 6%, and BKP 45%. NSM was usually appropriate in patients with a negative MRI or a positive MRI without other unfavorable conditions (poor outcomes for the other variables). VP was usually appropriate in patients with a positive MRI, time since fracture ≥ 6 weeks, and no spinal deformity. BKP was recommended for all patients with an ongoing fracture process, and also in most patients with a positive MRI and ≥ 1 other unfavorable factor. LIMITATIONS: The prevalence of the patient profiles in daily practice is yet unknown. CONCLUSION: The panel results may help to support treatment choice in the heterogeneous population of patients with osteoporotic VCF.


Assuntos
Fraturas por Compressão/cirurgia , Cifoplastia , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Feminino , Fraturas por Compressão/diagnóstico , Fraturas por Compressão/etiologia , Humanos , Cifoplastia/métodos , Masculino , Fraturas por Osteoporose/diagnóstico , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico , Fraturas da Coluna Vertebral/etiologia , Resultado do Tratamento
6.
ISME J ; 6(12): 2302-13, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23018772

RESUMO

Darkening of parts of the Greenland ice sheet surface during the summer months leads to reduced albedo and increased melting. Here we show that heavily pigmented, actively photosynthesising microalgae and cyanobacteria are present on the bare ice. We demonstrate the widespread abundance of green algae in the Zygnematophyceae on the ice sheet surface in Southwest Greenland. Photophysiological measurements (variable chlorophyll fluorescence) indicate that the ice algae likely use screening mechanisms to downregulate photosynthesis when exposed to high intensities of visible and ultraviolet radiation, rather than non-photochemical quenching or cell movement. Using imaging microspectrophotometry, we demonstrate that intact cells and filaments absorb light with characteristic spectral profiles across ultraviolet and visible wavelengths, whereas inorganic dust particles typical for these areas display little absorption. Our results indicate that the phototrophic community growing directly on the bare ice, through their photophysiology, most likely have an important role in changing albedo, and subsequently may impact melt rates on the ice sheet.


Assuntos
Cianobactérias/fisiologia , Camada de Gelo/microbiologia , Microalgas/fisiologia , Fotossíntese , Isótopos de Carbono/análise , Clorofila/análise , Congelamento , Groenlândia , Microespectrofotometria , Estações do Ano
7.
PLoS One ; 7(6): e38882, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22761712

RESUMO

Unmanned aerial vehicles (UAV), or drones, have been used widely in military applications, but more recently civilian applications have emerged (e.g., wildlife population monitoring, traffic monitoring, law enforcement, oil and gas pipeline threat detection). UAV can have several advantages over manned aircraft for wildlife surveys, including reduced ecological footprint, increased safety, and the ability to collect high-resolution geo-referenced imagery that can document the presence of species without the use of a human observer. We illustrate how geo-referenced data collected with UAV technology in combination with recently developed statistical models can improve our ability to estimate the distribution of organisms. To demonstrate the efficacy of this methodology, we conducted an experiment in which tennis balls were used as surrogates of organisms to be surveyed. We used a UAV to collect images of an experimental field with a known number of tennis balls, each of which had a certain probability of being hidden. We then applied spatially explicit occupancy models to estimate the number of balls and created precise distribution maps. We conducted three consecutive surveys over the experimental field and estimated the total number of balls to be 328 (95%CI: 312, 348). The true number was 329 balls, but simple counts based on the UAV pictures would have led to a total maximum count of 284. The distribution of the balls in the field followed a simulated environmental gradient. We also were able to accurately estimate the relationship between the gradient and the distribution of balls. Our experiment demonstrates how this technology can be used to create precise distribution maps in which discrete regions of the study area are assigned a probability of presence of an object. Finally, we discuss the applicability and relevance of this experimental study to the case study of Florida manatee distribution at power plants.


Assuntos
Aeronaves , Reconhecimento Automatizado de Padrão , Equipamentos Esportivos , Tênis , Trichechus , Animais , Simulação por Computador , Meio Ambiente , Humanos , Modelos Estatísticos
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