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171.

Objectives

To achieve international consensus across multiple specialties on a generic ultrasound rating scale using a Delphi technique.

Methods

Ultrasound experts from Obstetrics-Gynaecology, Surgery, Urology, Radiology, Rheumatology, Emergency Medicine, and Gastro-Enterology representing North America, Australia, and Europe were identified. A multi-round survey was conducted to obtain consensus between these experts. Of 60 invited experts, 44 experts agreed to participate in the first Delphi round, 41 remained in the second round, and 37 completed the third Delphi round. Seven key elements of the ultrasound examination were identified from existing literature and recommendations from international ultrasound societies. All experts rated the importance of these seven elements on a five-point Likert scale in the first round and suggested potential new elements for the assessment of ultrasound skills. In the second round, the experts re-rated all elements and a third round was conducted to allow final comments. Agreement on which elements to include in the final rating scale was pre-defined as more than 80% of the experts rating an element four or five, on importance to the ultrasound examination.

Results

Two additional elements were suggested by more than 10% of the experts in the first Delphi round. Consensus was obtained to include these two new elements along with five of the original elements in the final assessment instrument: 1) Indication for the examination 2) Applied knowledge of ultrasound equipment 3) Image optimization 4) Systematic examination 5) Interpretation of images 6) Documentation of examination and 7) Medical decision making.

Conclusion

International multispecialty consensus was achieved on the content of a generic ultrasound rating scale. This is the first step to ensure valid assessment of clinicians in different medical specialties using ultrasound.  相似文献   
172.
Genetic data have become increasingly useful for conservation planning when data regarding population status and long-term viability is limited. The Olympic mudminnow is the only fish species endemic to Washington State, USA. The species is an increasing priority for conservation given its limited distribution and increasing habitat loss. Presently, information important for developing conservation plans including population abundance data, knowledge of population boundaries, and estimates of gene flow among populations are limited. We used microsatellite markers to assess the level of genetic variation within and among Olympic mudminnow collections from 23 sites across the species range. Genetic variation within collections ranged widely and was greatest within the Chehalis River Basin, a former glacial refugium. Analysis of population boundaries showed that each collection site represented a unique population with the exception of collections made within two large wetland and stream complexes. Genetic variation among populations appears to be strongly influenced by glacial history and the species’ life history. Populations originating from the Chehalis River glacial refugium clustered together in multiple analyses and populations from the Olympic Coast, which persisted in separate refugia and have limited capacity for dispersal, showed a high level of differentiation. Competing theories existed regarding the origins of disjunct populations in east Puget Sound and genetic data showed that these populations represent undocumented introductions rather than a glacial remnant or historic colonization from the Chehalis refugium. Data presented in this study will help fill important information gaps and advance conservation planning for this species.  相似文献   
173.
174.

Objective

The main aim of this study was to assess whether a history of abuse, reported during pregnancy, was associated with an operative delivery. Secondly, we assessed if the association varied according to the type of abuse and if the reported abuse had been experienced as a child or an adult.

Design

The Bidens study, a cohort study in six European countries (Belgium, Iceland, Denmark, Estonia, Norway, and Sweden) recruited 6724 pregnant women attending routine antenatal care. History of abuse was assessed through questionnaire and linked to obstetric information from hospital records. The main outcome measure was operative delivery as a dichotomous variable, and categorized as an elective caesarean section (CS), or an operative vaginal birth, or an emergency CS. Non-obstetrically indicated were CSs performed on request or for psychological reasons without another medical reason. Binary and multinomial regression analysis were used to assess the associations.

Results

Among 3308 primiparous women, sexual abuse as an adult (≥18 years) increased the risk of an elective CS, Adjusted Odds Ratio 2.12 (1.28–3.49), and the likelihood for a non-obstetrically indicated CS, OR 3.74 (1.24–11.24). Women expressing current suffering from the reported adult sexual abuse had the highest risk for an elective CS, AOR 4.07 (1.46–11.3). Neither physical abuse (in adulthood or childhood <18 years), nor sexual abuse in childhood increased the risk of any operative delivery among primiparous women. Among 3416 multiparous women, neither sexual, nor emotional abuse was significantly associated with any kind of operative delivery, while physical abuse had an increased AOR for emergency CS of 1.51 (1.05–2.19).

Conclusion

Sexual abuse as an adult increases the risk of an elective CS among women with no prior birth experience, in particular for non-obstetrical reasons. Among multiparous women, a history of physical abuse increases the risk of an emergency CS.  相似文献   
175.
The nutritional value of various crops can be improved by engineering plants to produce high levels of proteins. For example, because methionine deficiency limits the protein quality of Medicago Sativa (alfalfa) forage, producing alfalfa plants that accumulate high levels of a methionine‐rich protein could increase the nutritional value of that crop. We used three strategies in designing methionine‐rich recombinant proteins that could accumulate to high levels in plants and thereby serve as candidates for improving the protein quality of alfalfa forage. In tobacco, two fusion proteins, γ‐gliadin‐δ‐zein and γ‐δ‐zein, as well as δ‐zein co‐expressed with β‐zein, all formed protein bodies. However, the γ‐gliadin‐δ‐zein fusion protein accumulated to the highest level, representing up to 1.5% of total soluble protein (TSP) in one transformant. In alfalfa, γ‐gliadin‐δ‐zein accumulated to 0.2% of TSP, and in an in vitro rumen digestion assay, γ‐gliadin‐δ‐zein was more resistant to microbial degradation than Rubisco. Additionally, although it did not form protein bodies, a γ‐gliadin‐GFP fusion protein accumulated to much higher levels, 7% of TSP, than a recombinant protein comprised of an ER localization signal fused to GFP in tobacco. Based on our results, we conclude that γ‐gliadin‐δ‐zein is a potential candidate protein to use for enhancing methionine levels in plants and for improving rumen stability of forage protein. γ‐gliadin fusion proteins may provide a general platform for increasing the accumulation of recombinant proteins in transgenic plants.  相似文献   
176.
Investigation of hip pain in a patient bearing a hip prosthesis is a common indication in Nuclear Medicine departments daily practice. Indeed, morphological cross-sectional imaging devices, such as MDCT and MRI, are often hampered by metallic implants. If planar bone scintigraphy is acknowledged with a high sensitivity, nonetheless, this exam specificity is poor. Since Anger cameras twinned with spiral CT (SPECT/CT) have appeared in the clinical arena, this limited specificity is compensated by the CT threefold input, all at once attenuation correction, localizing and diagnostic tool. Bone SPECT/CT requires that the Nuclear Medicine physician upgrades his knowledge of bone and joint anatomy, CT patterns, but foremost, data merging from SPECT and CT. The aim of this article is to sketch out bone SPECT/CT role and patterning in miscellaneous complications following arthroplasty, explained by pathophysiological mechanisms.  相似文献   
177.
The phenotypic analysis of root system growth is important to inform efforts to enhance plant resource acquisition from soils; however, root phenotyping remains challenging because of the opacity of soil, requiring systems that facilitate root system visibility and image acquisition. Previously reported systems require costly or bespoke materials not available in most countries, where breeders need tools to select varieties best adapted to local soils and field conditions. Here, we report an affordable soil‐based growth (rhizobox) and imaging system to phenotype root development in glasshouses or shelters. All components of the system are made from locally available commodity components, facilitating the adoption of this affordable technology in low‐income countries. The rhizobox is large enough (approximately 6000 cm2 of visible soil) to avoid restricting vertical root system growth for most if not all of the life cycle, yet light enough (approximately 21 kg when filled with soil) for routine handling. Support structures and an imaging station, with five cameras covering the whole soil surface, complement the rhizoboxes. Images are acquired via the Phenotiki sensor interface, collected, stitched and analysed. Root system architecture (RSA) parameters are quantified without intervention. The RSAs of a dicot species (Cicer arietinum, chickpea) and a monocot species (Hordeum vulgare, barley), exhibiting contrasting root systems, were analysed. Insights into root system dynamics during vegetative and reproductive stages of the chickpea life cycle were obtained. This affordable system is relevant for efforts in Ethiopia and other low‐ and middle‐income countries to enhance crop yields and climate resilience sustainably.  相似文献   
178.
Knowledge of vegetation dynamics associated with human land-use change and environmental variables is crucial for sustainable watershed management. The objective of this study was to analyse woody plant diversity in response to the effects of anthropogenic disturbances, and topographic variables in different land-cover types. Woody plants ≥5 cm diameter at breast height (DBH) were recorded from 20-by-20 m plots, those <5 cm DBH were recorded from 10-by-10 m plots, and tree seedlings were recorded in 3-by-3 m plots. Nonmetric multidimensional scaling with Bray–Curtis distance was employed to analyse woody species composition. Woody species richness was analysed using generalised linear modelling. Tree diameter-class distributions were examined for population structure. The study identified 104 woody plants belonging to 52 families, where 74.5% were indigenous and 16.7% were endemic to Ethiopia. Asteraceae, Fabaceae and Rosaceae were the most species-rich families. There was evidence for the effect of anthropogenic disturbance and elevation on woody species composition. Wetlands contained the highest woody species richness, while woody species richness declined with increasing elevation and disturbance. Evidence of good regeneration was observed in wetlands. To sustain the ecological functions and services provided by the watershed, rehabilitation of the forest and shrub-cover should be a high priority for local management authorities.  相似文献   
179.
180.
The fungus Magnaporthe grisea, commonly referred to as the rice blast fungus, is responsible for destroying from 10% to 30% of the world's rice crop each year. The fungus attaches to the rice leaf and forms a dome-shaped structure, the appressorium, in which enormous pressures are generated that are used to blast a penetration peg through the rice cell walls and infect the plant. We develop a model of the appressorial design in terms of a bioelastic shell that can explain the shape of the appressorium, and its ability to maintain that shape under the enormous increases in turgor pressure that can occur during the penetration phase.  相似文献   
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