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A global climatology of windâwave interaction
Generally, ocean waves are thought to act as a drag on the surface
wind so that momentum is transferred downwards, from the atmosphere
into the waves. Recent observations have suggested that when long
wavelength waves, characteristic of remotely generated swell,
propagate faster than the surface wind momentum can also be
transferred upwards. This upward momentum transfer acts to accelerate
the near-surface wind, resulting in a low-level wave-driven wind
jet. Previous studies have suggested that the sign reversal of the
momentum flux is well predicted by the inverse wave age, the ratio of
the surface wind speed to the speed of the waves at the peak of the
spectrum. ECMWF ERA-40 data has been used here to calculate the global
distribution of the inverse wave age to determine whether there are
regions of the ocean that are usually in the wind-driven wave regime
and others that are generally in the wave-driven wind regime. The
wind-driven wave regime is found to occur most often in the
mid-latitude storm tracks where wind speeds are generally high. The
wave-driven wind regime is found to be prevalent in the tropics where
wind speeds are generally light and swell can propagate from storms at
higher latitudes. The inverse wave age is also a useful indicator of
the degree of coupling between the local wind and wave fields. The
climatologies presented emphasise the non-equilibrium that exists
between the local wind and wave fields and highlight the importance of
swell in the global oceans
Sinonasal undifferentiated carcinoma and esthesioneuroblastoma recurring as nonintestinal adenocarcinoma
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97478/1/lary23746.pd
Perioperative lumbar drain placement: An independent predictor of tension pneumocephalus and intracranial complications following anterior skull base surgery
Objective: To measure the effect of routine perioperative lumbar drain placement during anterior skull base surgery on the frequency of: 1) tension pneumocephalus and 2) total intracranial complications. Design: Retrospective review of a series of patients (n = 161) who underwent the transglabellar/subcranial approach to lesions of the anterior skull base between December 1995 and November 2009. A retrospective cohort (n = 45) underwent routine lumbar drain placement at the time of skull base surgery. The remainder of the series did not undergo routine perioperative lumbar drain placement. Intervention: Transglabellar/subcranial surgical approach to the anterior skull base, with or without routine perioperative lumbar drain placement. Results: Routine placement of perioperative lumbar drains was an independent predictor of tension pneumocephalus ( P =.022, odds ratio = 11.22 [1.218â103.3]). In addition, this practice was also associated with an increased risk of intracranial complications overall ( P =.025, odds ratio = 2.623 [1.104â6.233]). Conclusion: Routine placement of perioperative lumbar drain may be associated with an increased risk of tension pneumocephalus and intracranial complications during surgery of the anterior cranial base. Laryngoscope, 2011Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/84402/1/21409_ftp.pd
Olfactory groove meningioma: Discussion of clinical presentation and surgical outcomes following excision via the subcranial approach
Objectives/Hypothesis: To describe surgical outcomes and radiographic features of olfactory groove meningiomas treated by excision through the subcranial approach. Special emphasis is placed on paranasal sinus and orbit involvement. Study Design: Retrospective review of a series of patients. Methods: Nineteen patients underwent excision of olfactory groove meningioma (OGM) via the transglabellar/subcranial approach between December 1995 and November 2009. Nine patients had previously undergone prior resection at outside institutions, and four had prior radiotherapy in addition to a prior excision. Transglabellar/subcranial surgical approach to the anterior skull base was performed. Results: Tumor histology included three World Health Organization (WHO) grade III lesions, one WHO grade II lesion, and 15 WHO grade I lesions. Fourteen patients had evidence of extension into the paranasal sinuses, with the ethmoid sinus being most commonly involved. KaplanâMeier estimates of mean overall and diseaseâfree survival were 121.45 months and 93.03 months, respectively. The mean followâup interval was 41.0 months, and at the time of data analysis three patients had recurrent tumors. Seven (36.8%) patients experienced a major complication in the perioperative period; there were no perioperative mortalities. Orbit invasion was observed in four patients, with optic nerve impingement in 11 patients. Of these, three patients had longâterm diplopia. No patients experienced worsening of preoperative visual acuity. Conclusions: Olfactory groove meningiomas demonstrate a propensity to spread into the paranasal sinuses, particularly in recurrent cases. Given a tendency for infiltrative recurrence along the skull base, this disease represents an important area of collaboration between neurosurgery and otolaryngology. The subcranial approach offers excellent surgical access for excision, particularly for recurrences that involve the paranasal sinuses and optic apparatus.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87044/1/22174_ftp.pd
Studies in Dye-Tracing Technologies in Karst Hydrogeology
Information on fluorescent dyes used for water tracing and the results of six studies are reported. Optical brightener, direct yellow, fluorescein, rhodamine (WT), and other dyes are described and the procedures employed in their use ·in the field and in equilibration experiments are discussed. Three of the six studies consisted of investigations of the equilibration with passive detectors of three of the dyes. The absorption of optical brightener on fabric detectors was apparently linear with concentration and with immersion time, while detectors became rapidly saturated with direct yellow. Equilibrium of fluorescein on charcoal detectors with an elutriating solution was not achieved.
Several data processing tasks were performed, including the creation of a computer file for field data and the writing-of programs to sort the field data and generate plotted maps, and to display the total fluorescence of samples. A fifth study was based. on a series of dye traces into Royal Spring and Russell Cave Spring in the Inner Bluegrass Karst Region. Samples were collected with an automatic water sampler and the resulting flow velocity determinations combined with discharge data provided values at a number of aquifer parameters. The most interesting result was the very small value for depth of flow. A final study was of fracture traces identified on topographic maps and aerial photographs in the Inner Bluegrass Karst Region. It was found that while more such features were visible on the photographs, some were only apparent on maps
Resistance training volume, energy balance and weight management: Rationale and design of a 9 month trial
The increased prevalence of obesity and the lack of treatment success both argue for the design and evaluation of strategies to prevent the development of overweight and obesity. To date, the role of resistance training (RT) in this regard is largely unexplored. RT may be effective for weight management as a result of increased fat-free mass (FFM), which may result in increased resting metabolic rate and increased physical activity energy expenditure. However, the literature relative to the efficacy of RT protocols recommended for healthy adults to alter the aforementioned parameters is inconsistent or inadequately evaluated. We will conduct a 9 month randomized controlled efficacy trial to compare changes in body composition (fat mass, FFM, % body fat) and energy balance in response to 2 volumes of RT (1 vs. 3 sets vs. non-exercise control) both at the completion of training (9 months) and 1 year later (body composition). This investigation will be conducted in a sample of healthy, normal and overweight, sedentary, young adult men and women; a group at high risk for development of overweight and obesity. Our results will provide information relative to the minimum volume of RT that may be associated with body weight/fat gain which may inform the development of guidelines for RT to prevent weight gain or to alter body composition
Photo-assisted recall increases estimates of energy and macronutrient intake in adults with intellectual and developmental disabilities
Diet assessment of adults with intellectual and developmental disabilities (IDD) is challenging due to their limited cognitive abilities. The objective of this study was to examine the feasibility and outcomes of combining photos with 24-hour dietary recalls for the assessment of energy and macronutrient intake in adults with IDD. Participants used an iPad 2 tablet computer to take photos of all food and beverages consumed before a standard, multiple-pass, 24-hour dietary recall. Following the standard 24-hour diet recall, the photos were reviewed with the participant for clarification details (e.g., portion size, etc.) and differences were recorded. The standard 24-hour recall and the photo-assisted recall were entered separately into Nutrition Data System for Research for computerized dietary analysis. Sixty-four eating occasions were entered from 23 participants (48% female; mean age 26.4 ±9.7 years). Participants captured photos for 66.5% ± 30.4% of all recorded eating occasions. Greater energy intake per eating occasion was reported with the photo-assisted recalls than the standard recalls (625.6 ± 85.7 kcals vs. 497.2 ± 86.6 kcals, p=0.002) and a greater intake of grams of fat (p=0.006) protein (p=0.029) and carbohydrates (p=0.003). Photo-assisted 24-hour recalls provided a significant increase in total calories and macronutrient content compared to a standard 24-hour recall and may be a feasible method to enhance dietary assessment in adults with IDD
Water quality in the eastern Iowa basins
This article summarizes major findings about nutrients in surface and groundwater in the eastern Iowa basins (see map) between 1996 and 1998. The data were collected as part of the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA). Water quality is discussed in terms of local and regional issues and compared with conditions found in all 36 National NAWQA study areas assessed to date. Findings are explained in the context of selected national U.S. Environmental Protection Agency (EPA) benchmarks, such as those for drinking water quality and the protection of aquatic organisms
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