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A 1.6-yr time series of radial current velocity from a 25-MHz high-frequency radar system located near a coastal river plume is analyzed to determine how the working range varies in response to changing near-surface conductivity, sea state, and tides. Working range is defined as the distance to the farthest radial velocity solution along a fixed bearing. A comparison to spatially resolved near-surface conductivity measurements from an instrumented ferry shows that fluctuations in conductivity had the largest impact of the three factors considered. The working range increases nearly linearly with increasing conductivity, almost doubling from 19.4 km at 0.9 S m21 to 37.4 km at 3.5 S m21, which yields a slope of 7.0 km per S m21. The next largest factor was sea state, which was investigated using measured winds. The working range increases linearly at a rate of 1 km per ms21 of wind speed over the range of 0.5-6.5 ms21, but it decreases weakly for wind speeds higher than 7.5 ms21. Finally, a power spectrum of the working range time series reveals variability at tidal frequencies. Tides cause about 3 km of range variation; however, the mechanism(s) underlying this are not known explicitly. Evidence for both sea level height and the interaction of tidal currents with sea state are presented. [ABSTRACT FROM AUTHOR]

Background: Much has been written regarding the incidence, types, importance and management of abdominal CT incidental findings in adults, but there is a paucity of literature on incidental findings in children. Objective: We sought to determine the prevalence and characteristics of extra-appendiceal and incidental findings in pediatric abdominal CT performed for suspected appendicitis. Materials and methods: A retrospective review was performed of abdominal CT for suspected appendicitis in a pediatric emergency department from July 2010 to June 2012. Extra-appendiceal findings were recorded. Any subsequent imaging was noted. Extra-appendiceal findings were divided into incidental findings of doubtful clinical significance, alternative diagnostic findings potentially providing a diagnosis other than appendicitis explaining the symptoms, and incidental findings that were abnormalities requiring clinical correlation and sometimes requiring further evaluation but not likely related to the patient symptoms. Results: One hundred sixty-five children had abdominal CT for suspected appendicitis. Seventy-seven extra-appendiceal findings were found in 57 (34.5%) patients. Most findings (64 of 77) were discovered in children who did not have appendicitis. Forty-one of these findings (53%) could potentially help explain the patient's symptoms, while 30 of the findings (39%) were abnormalities that were unlikely to be related to the symptoms but required clinical correlation and sometimes further work-up. Six of the findings (8%) had doubtful or no clinical significance. Conclusion: Extra-appendiceal findings are common in children who undergo abdominal CT in the setting of suspected appendicitis. A significant percentage of these patients have findings that help explain their symptoms. Knowledge of the types and prevalence of these findings may help radiologists in the planning and interpretation of CT examinations in this patient population. [ABSTRACT FROM AUTHOR]

Highlights: [•] Velocity profiles from moored ADCPs are used to quantify the nature of the exchange. [•] The barotropic EOF mode constitutes more than 62% of the subtidal variance. [•] Tides drive the largest fluctuations in transport, but have little net effect. [•] Wind forcing is the dominant subtidal driver, peaking at 4 to 5-day time scales. [•] Wind drives most of the subtidal transport by setting up sea level in and around PWS. [ABSTRACT FROM AUTHOR]

This toxic effect can mimic Guillain-Barré syndrome clinically but does not lead to brain or spinal cord or nerve root imaging findings on CT or MRI. Radiologists can help make the diagnosis of tick paralysis if they are aware of the need to include the scalp in their search pattern in cases of ascending paralysis, and if they recognize the imaging appearance of the tick itself. Dear Editors, Just over a century ago, physicians John Todd [[1]] and Seymour Hadwen [[2]], in British Columbia, Canada, began research into local cases of acute ascending paralysis in children that seemed related to ticks most commonly found in the Pacific Northwest region of North America. [Extracted from the article]

Background: The term 'radiopaque' is commonly used when discussing foreign bodies and lists of radiopaque and non-radiopaque materials are sometimes created, but radiopacity is not a binary concept. A more fundamental understanding of radiopacity is necessary for the work-up of foreign bodies. Objective: To demonstrate that 'radiopaque' is a relative term. Materials and methods: Twenty foreign bodies of various sizes, shapes and materials were placed in a basin. Radiographs were obtained of the objects with 0, 2.5, 5 and 10 cm depth of water in the basin to simulate the appearance of a foreign body in human tissue. The progressively changing appearance of the objects was observed. Results: All of the objects were radiographically visible in the empty basin. Different objects demonstrated different appearances when immersed in progressively deeper levels of water, illustrating the effect of the surrounding water as well as the effects of object shape, size, orientation and composition. Conclusion: The concept of radiopacity seems simple and the term 'radiopaque' is sometimes used to describe an all or none phenomenon. However, radiopacity is a comparative concept implying relative X-ray attenuation. Accurate understanding of the radiographic appearance of foreign bodies requires one to keep in mind the concepts of relative X-ray attenuation and contrast resolution. [ABSTRACT FROM AUTHOR]

Abstract: An instrumented ferry made eight transects per day across the Fraser River plume over the years 2003–2006 as part of the STRATOGEM program studying biophysical coupling in the Strait of Georgia, British Columbia, Canada. Seawater properties inside and outside the Fraser plume were measured with high spatial and temporal resolution for an extended period. Here the salinity and chlorophyll-a fluorescence records are used to determine how the Fraser River plume affects phytoplankton biomass in the Strait of Georgia over a range of time scales. The fluorescence record is corrected for non-photochemical quenching by comparison of daytime and nighttime samples, and then calibrated in a manner traceable to extracted chlorophyll measurements. Analysis shows that the instantaneous along-track structure of near-surface chlorophyll-a is often sensitive to the presence of the Fraser River plume. However, when averaged over the 4-year time series, the plume has little impact. Depth-integrated chlorophyll-a biomass is then estimated by applying scaling factors derived from vertical profiles. Unlike the near-surface measurements, depth-integrated biomass in the plume is on average only 74% of the amount found in neighboring waters. Potential reasons for this discrepancy are discussed in terms of light attenuation, the vertical distribution of chlorophyll-a, plume fresh water fraction, and flushing time. [Copyright &y& Elsevier]

Abstract: Salinity, temperature, and depth profiles from 1973 to 2010 were used to construct a seasonal climatology of surface temperature, surface salinity, mixed layer depth (MLD), potential energy of mixing, and surface geostrophic circulation in Prince William Sound (PWS) and the adjacent Gulf of Alaska. Surface salinity is greatest in winter and least in summer due to the influence of increased freshwater runoff in summer. It is generally lowest in the northwest and highest in the Gulf of Alaska. The surface temperature is lowest in the winter and highest in the summer when surface heating is greatest, with little spatial variability across the Sound. The MLD is deepest in winter (9–27m) and shallowest in summer (4–5m). The work by winds was estimated from meteorological buoy data in central PWS and compared to the potential energy of mixing of the upper water column. The potential depth to which winds mix the upper water column was generally consistent with the MLD. The surface geostrophic circulation in the central Sound has: a southerly flow in the western central Sound in the winter; a closed, weak anticyclonic cell in spring; a closed, cyclonic cell in the summer; an open, cyclonic circulation in the fall. In the western passages, a southerly flow occurs in spring, summer, and fall. These results have important implications for oil spill response in PWS, the use of oil dispersants, and for comparison to numerical studies. [Copyright &y& Elsevier]

This paper takes a broad overview of the reliability and safety engineering practice as it is commonly exercised in the aerospace and military industries today, especially with respect to complex electronic equipment which typically includes considerable software content. A general deficiency is noted with regard to the system-level approach to reliability. It would appear that the system-level reliability activities are given less attention than is needed, while excessive emphasis is placed on component micro-physics, component failure models, and various component-oriented analyses. Systems-level reliability topics, which predominate in the equipment reliability which is actually observed, are sometimes ignored by reliability engineers. Methods and practical philosophies to re-establish a solid system engineering foundation for contemporary reliability practice, which have been developed through the authors' experience in the field, are presented. Finally, an example analysis is shown to illustrate the concepts. [ABSTRACT FROM AUTHOR]

Building energy code compliance is the crucial link between the actual energy savings and the efficiency prescribed in energy codes. A research project aiming to identify opportunities to reduce energy consumption in new single-family residential construction by increasing compliance with the building energy code was conducted in several states of the United States. The study was comprised of three phases: (1) a baseline study to document typical practice and identify opportunities for improvement based on empirical data gathered from the field; (2) an education and training phase targeting the opportunities identified; and (3) a post-study to assess whether a reduction in average state-wide energy use could be achieved following the education and training phase. We proposed a novel methodology based on large-scale building energy simulation inferred by limited field data to assess the performance of a large population of homes. This paper presents the methodology, findings, and results of this study. The state-wide average energy consumption decreased at Phase III from Phase I for five of the seven states involved in the analysis. The measure-level savings potential analysis shows an overall reduction. Overall, the training and education phase plays a recognizable role in improving compliance with building energy codes. [ABSTRACT FROM AUTHOR]

This study demonstrates the long-term stability of salinity measurements from Argo floats equipped with inductive conductivity cells, which have extended float lifetimes as compared to electrode-type cells. New Argo float sensor payloads must meet the demands of the Argo governance committees before they are implemented globally. Currently, the use of CTDs with inductive cells designed and manufactured by RBR, Ltd., has been approved as a Global Argo Pilot. One requirement for new sensors is to demonstrate stable measurements over the lifetime of a float. To demonstrate this, data from four Argo floats in the western Pacific Ocean equipped with the RBRargo CTD sensor package are analyzed using the same Owens–Wong–Cabanes (OWC) method and reference datasets as the Argo delayed-mode quality control (DMQC) operators. When run with default settings against the standard DMQC Argo and CTD databases, the OWC analysis reveals no drift in any of the four RBRargo datasets and, in one case, an offset exceeding the Argo target salinity limits. Being a statistical tool, the OWC method cannot strictly determine whether deviations in salinity measurements with respect to a reference hydrographic product (e.g., climatologies) are caused by oceanographic variability or sensor problems. So, this study furthermore investigates anomalous salinity measurements observed when compared with a reference product and demonstrates that anomalous values tend to occur in regions with a high degree of variability and can be better explained by imperfect reference data rather than sensor drift. This study concludes that the RBR inductive cell is a viable option for salinity measurements as part of the Argo program. [ABSTRACT FROM AUTHOR]

In case 1, we hypothesise that the cephalohaematoma developed into subgaleal abscess with bacterial seeding from the antecedent urinary tract infection. The blood culture was also negative, white cell count (WCC) was 5.7 × 10 SP 9 sp /L and C-reactive protein (CRP) was 77.4 mg/L. Cranial ultrasound showed a lentiform 8.9 × 6.9 cm collection consistent with a large uncomplicated cephalohaematoma. If the cephalohaematoma does show signs of localised infection with possible extension, appropriate imaging with high diagnostic yield for osteomyelitis (CT or magnetic resonance imaging) is warranted with consideration given to debridement. [Extracted from the article]

Background: Surgical resection is the treatment of choice for pleomorphic xanthoastrocytoma, while chemotherapy and radiation therapy are typically used in patients with anaplasia, metastasis, or sometimes in subtotally resected cases, especially upon recurrence. Extracranial dissemination has been only rarely reported. We describe a five year old boy with the rare occurrence multiply recurrent and extracranially disseminated anaplastic pleomorphic xanthoastrocytoma. A complete resolution of his tumor was achieved for greater than two years thus far after administering everolimus.Methods: We performed a comprehensive literature review of all pleomorphic xanthoastrocytoma cases; 359 cases were described, and 132 of these individuals were less than 18 years of age.Results: Gross total resection was achieved in only 132 (36.7%) cases, while additional therapy was administered in 186 patients. Only four patients in additon to our own have been documented with extracranial dissemination (four of five in the pediatric population); two patients who succumbed to their disease underwent subtotal resection of the primary tumor.Conclusions: We report the first patient with extracranially disseminated anaplastic pleomorphic xanthoastrocytoma to be successfully maintained on everolimus as a single oral chemotherapy agent with complete resolution of the tumor. Pleomorphic xanthoastrocytoma can rarely disseminate extracranially in the pediatric population, hence pathologists and neuro-oncologists should be aware of this possibility. [ABSTRACT FROM AUTHOR]