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Multipactor breakdown is a resonant electron phenomena that is observed in spacecraft RF systems. While multipactor breakdown thresholds are well documented for parallel metal surfaces, susceptible breakdown geometries in passive RF components frequently deviate from this ideal parallel-plate geometry. A common feature of concern is an angled or chamfered edges placed on dielectrics inside RF components. Using a 3D electromagnetic tool coupled with an electron tracking tool, a simplified angled gap geometry is analyzed. The breakdown threshold increase from a parallel gap to an angle gap is calculated and discussed. The analysis results will be compared with laboratory measurements to demonstrate the applicability of this analysis technique.

Multipactor breakdown may occur in an RF component when the electron transit time across a gap satisfies a resonant condition and the secondary electron yield from surfaces is sufficiently high to overcome electron losses from the breakdown region and produce net electron population growth. In devices such as isolators and circulators that have a magnetic field oriented parallel to the RF electric field, transverse mobility of electrons is inhibited. This electron confinement reduces losses and can lower the multipactor threshold power by several decibels compared to the unmagnetized case. Fundamentals of this process have been studied in a simple stripline geometry with an externally applied uniform magnetic field of variable strength. Laboratory experiments are compared with particle tracking simulations as well as an analytical theory that takes into account the distribution of secondary emission energies.

A single long trench was excavated as preparation for a concrete foundation for a flood defense wall. No archaeological finds or features were observed during this watching brief. The natural ground was truncated to a depth of 25.60mOD and consisted of a yellow brown sandy clay overlying a gravel terrace.

Hilary Vernon1,21McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University, 2Kennedy Krieger Institute, Baltimore, MD, USAAbstract: Phenylketonuria (PKU) is an inborn error of metabolism caused by a defect in the enzyme phenylalanine hydroxylase, which is responsible for converting phenylalanine to tyrosine. Untreated, this disorder will result in severe intellectual disability. However, with proper management, outcome is excellent. For many years, this disorder was managed exclusively with dietary measures which consisted of a phenylalanine-restricted diet. However, with the recent introduction of a stable, orally bioavailable form of tetrahydrobiopterin (BH4), the cofactor for phenylalanine hydroxylase, treatment in this disorder has been drastically altered. This stable form of BH4, sapropterin dihydrochloride, has a very good safety profile and is very effective in many patients with PKU in lowering plasma phenylalanine levels and allowing for liberalization of the phenylalanine-restricted diet. The introduction of BH4 has posed many new challenges in the treatment of PKU, including developing the best protocol to determine whether or not a patient will respond to BH4, and how to treat atypical populations including young children, fully affected, untreated adults, and pregnant patients. In this review, we will examine the history of treatment in PKU, the history of treatment with BH4, protocol options for determining if a patient is a drug responder, and considerations for treatment in special populations.Keywords: sapropterin dihydrochloride, phenylketonuria, phenylalanine

The Brazilian asset-backed security (ABS) market presents many opportunities and obstacles to investors, especially foreign investors who are accustomed to transparent markets and a wealth of information. This article shows that financial models can actually help with this problem, if they are used correctly. Rather than taking the data for the structures at face value and feeding them to a financial model in one direction, this approach utilizes a feedback loop in which the model benchmarks the performance of the security. The author shows how this approach can be used to evaluate and track the risks in this evolving market by analyzing two similar deals with different structures and tracking their performance from 2007–2009. The analysis focuses on the tumultuous life of Fundo de Investimento em Direitos Creditorios (FIDC) PanAmericano Veiculos I, a Brazilian FIDC backed with vehicle loans that were originated by Banco PanAmericano. This FIDC is the perfect subject for such a study. It encountered the “perfect storm” of problems. Its investors were lucky to have received their capital back, as well as to have earned the indicated return. The FIDC matured five months before Banco PanAmericano was restructured because of a massive fraud carried out by management. The FIDC survived only because the bank was able to support the deal through frequent transfusions of new loans and the lax enforcement of regulations in Brazil.The model proposed here was used to analyze FIDC PanAmericano Veiculos I during this turbulent period.

Background:It is unclear whether recognition of epidural catheter failures is delayed with combined spinal epidural technique (CSE) compared to traditional epidural technique (EPID) when used for labor analgesia. The authors hypothesized that recognition of failed catheters is not delayed by CSE.Met

Ethnopharmacological relevance It is becoming increasingly clear that ethnopharmacology cannot be disassociated from food production, human nutrition and the conservation of the biodiversity that constitutes its resource base. Aim of the study This paper aims to provide a perspective of ethnopharmacology that explicitly extends the range of disciplines it covers so as to embrace food and nutrition and the biodiversity basis, both wild and agricultural, and also places it in the context of the dramatic changes to our planet that we are experiencing during a period of rapid global change and the impacts that these changes are having on human health and nutrition and on its resource base. Materials and methods A review is made of recent initiatives and developments that show linkages between ethnopharmacology, agriculture, food production, nutrition and biodiversity conservation. Results Ethnopharmacology, biodiversity, agriculture, food and nutrition are inextricably linked but suffer from compartmentalization and a lack of communication which have to be overcome if progress is to be made. Fortunately, a convergence of interest between the agricultural biodiversity and the biodiversity conservation sectors has emerged in recent years and there is an increased appreciation of the need to adopt a wider approach to human nutrition than the conventional agricultural model allows; there is also a greater awareness of the important role played by diversity of crops, especially local species, and consumption of wild species in achieving balanced nutrition. An increased recognition of the key role of local communities in managing agricultural biodiversity is evident. While ethnopharmacologists have expressed concern at the relentless loss of biodiversity, there has been little direct involvement but it is perhaps now time to consider a more proactive role. Attention is also drawn to the need to assess the implications of global change for ethnopharmacology. Conclusions Ethnopharmacologists need to take much more cognizance of the fate of the resource base – the plants, animals and microorganisms – and of the actions being undertaken under the auspices of treaties, such as the Conservation on Biological Diversity and its Global Strategy for Plant Conservation, and the International Treaty on Plant Genetic Resources for Food and Agriculture, to counter its degradation and loss. In addition, they should play a more active role in determining the actions needed to assess, monitor and conserve the resource base. Although it has been suggested that the ‘golden days’ of ethnopharmacology may be over, it is proposed that by embracing the challenges of broadening the remit so as to include the health aspects of wild biodiversity employed in nutrition, a new ‘golden age’ beckons. The paper concludes with some suggestions for action.

Percutaneous coronary intervention (PCI) in acute myocardial infarction (MI) has been associated with a high incidence of slow-, no-reflow. The slow-, no-reflow phenomenon is known to complicate both thrombolytic therapy and PCI. Removing intracoronary thrombus before PCI in acute MI patients may reduce the incidence of slow-, no-reflow phenomena. We studied the procedural outcome of 21 patients who underwent rheolytic thrombectomy using Possis® rheolytic thrombectomy catheter in the setting of acute MI as compared to twenty-eight patients who underwent PCI in the setting of acute MI using other modalities (PTCA with or without stenting) without thrombectomy. The study included 49 consecutive patients with 21 patients in the rheolytic thrombectomy group, and 28 patients in the no-rheolytic thrombectomy group. There was no significant difference between the two groups as regards to gender, age, and prevalence of coronary artery risk factors. The left ventricular ejection fraction was 44.7 ± 12 in the rheolytic thrombectomy group, and 37.6 ± 10.8 in the no-rheolytic thrombectomy group (p = 0.08). Thirty eight percent of the patients in the rheolytic thrombectomy group experienced slow flow, no-reflow, while 28.6% of the patients in the no-rheolytic thrombectomy group experienced slow flow, no-reflow (p = 0.5). In this matched series of patients with acute MI undergoing PCI, rheolytic thrombectomy by the Possis rheolytic thrombectomy catheter device does not appear to reduce the risk of slow flow, no-reflow, or in-hospital death, compared to standard PTCA and stenting of the infarct-related artery.

In light of the growing concern over the potentially devastating impacts on biodiversity and food security of climate change and the massively growing world population, taking action to conserve crop wild relatives (CWR), is no longer an option — it is a priority. Crop wild relatives are species closely related to crops, including their progenitors, many of which have the potential to contribute beneficial traits to crops, such as pest or disease resistance, yield improvement or stability. They are a critical component of plant genetic resources for food and agriculture (PGRFA), have already made major contributions to crop production and are vital for future food security; their systematic conservation in ways that ensure their continuing availability for use is therefore imperative. This is a complex, interdisciplinary, global issue that has been addressed by various national and international initiatives. Drawing on the lessons learnt from these initiatives we can now propose a global approach to CWR conservation, the key elements of which are: (1) estimating global CWR numbers, (2) assessment of the global importance of CWR diversity, (3) current conservation status, (4) threats to CWR diversity, (5) systematic approaches to CWR conservation, (6) CWR informatics, and (7) enhancing the use of CWR diversity.

While Murphy et al are clear in their findings and robust in their recommendations,1 they appear to regard malnutrition (and particularly undernutrition) as a diagnosis to be treated in its own …

One of the consequences of global change, especially demographic and climatic, will be a demand for novel plant germplasm of all kinds suited to the new ecoclimatic conditions predicted and plant introduction will assume a new importance. As a consequence, botanic gardens will face an unprecedented opportunity to regain their role as introduction centres and become major actors in the assessment of new germplasm, both of ornamentals as well as other economically important plants. Plant introduction has remained largely unchanged over the past 400 years and is as often ad hoc, poorly organized and insufficiently collaborative, but if it is to meet the needs of today’s situation it needs to be overhauled. In particular: (1) the basis of plant introduction needs to be broadened; (2) closer cooperation with agricultural genebanks should be established; (3) agreement should be reached between botanic gardens and the agricultural sector on their respective responsibilities (4) the quality and sampling of the accessions should be more strictly controlled; (5) proper evaluation of the introductions before they are disseminated; (6) information on the accessions of introduced plants and their fate needs to be more effectively maintained and disseminated; and (7) full cognizance should be taken of policies to protect against invasive species and care should be taken to evaluate the risks that new introductions might represent. Finally, consideration should be given to preparing a set of guidelines or even a code of conduct for plant introductions by botanic gardens in association with other agencies.

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Background Comparison of air versus saline for loss of resistance technique (LORT) in combined spinal epidural labor analgesia (CSE) has not been evaluated, and neither has the relation between CSE characteristics (the presence/absence of initial spontaneous clear fluid return or upon aspiration) and spinal/epidural analgesia outcomes. The authors hypothesized that there is no difference in the spinal analgesia success or epidural catheter efficacy between using air versus saline LORT for CSE. Methods A total of 360 patients were randomized to air or saline LORT for CSE. Primary outcome was spinal analgesia success as defined by verbal pain score of no more than 3 at 15 min after spinal dose administration. Secondary outcomes were CSE characteristics, catheter replacement, and average hourly epidural drug consumption. Results Results from 345 patients were analyzed. Spinal analgesia success, epidural catheter replacement, and drug consumption were not different between using air or saline LORT and were also independent of the presence/absence of fluid return on aspiration if initial spontaneous fluid returned to the spinal needle. However, epidural catheters inserted in absence of initial fluid return had a significantly higher catheter replacement rate (28.6%) than the 4.1% among those with initial fluid return (P < 0.03). Conclusions Spinal analgesia success rate and epidural efficacy are independent of whether air or saline is used for LORT during CSE. Practice of aspiration for fluid after observing initial fluid return may be unnecessary because this practice does not alter spinal/epidural analgesia outcomes. However, epidural catheters inserted with the absence of initial fluid returned to spinal needle may pose a high failure risk.

This study examines the factor structure of scores on the Four Dimension Mood Scale (4DMS) developed by Huelsman, Nemanick, and Munz in response to criticisms of the Positive and Negative Affect Schedule. The results showed that the factor structure of 4DMS scores obtained with a sample of U.K. residents assessed for state affect corresponded closely to that obtained by Huelsman et al. with hospital employees in the United States who were assessed for trait affect. The four-factor model provided a reasonably good fit to the scores and fitted better than one-factor or two-factor models, thus favoring a four-dimension model of affect. It was concluded that the 4DMS is appropriate for use in the United Kingdom with comparable samples. The study identified differences in composition of the 4DMS and Thayer's Activation Deactivation Adjective Check List, especially in the Tiredness scale, and areas for further investigation of the 4DMS.