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Background Obesity and insulin resistance are positively correlated with plasma endothelin-1 (ET-1) levels; however, the mechanisms leading to increased ET-1 are not understood. Similarly, the full physiological complexity of ET-1 has yet to be described, especially in obesity. To date, one of the best treatments available for morbid obesity is bariatric surgery to quickly reduce body fat and the factors associated with obesity-related disease; however, the effects of vertical sleeve gastrectomy (SG) on plasma ET-1 have not been described. Objectives To determine if SG will reduce plasma ET-1 levels and to determine if plasma ET-1 concentration is associated with weight loss after surgery. Setting The studies were undertaken at a University Hospital. Methods This was tested by measuring plasma ET-1 levels from 12 obese patients before and after SG. All data were collected from clinic visits before SG, 6 weeks after SG, and 6 months after surgery. Results At 6 weeks after SG, plasma ET-1 levels increased by 24%; however, after 6 months, there was a 27% decrease compared with presurgery. Average weight loss in this cohort was 11.3% ± 2.4% body weight after 6 weeks and 21.4% ± 5.7% body weight after 6 months. Interestingly, we observed an inverse relationship between baseline plasma ET-1 and percent body weight loss (R2 = .49, P = .01) and change in body mass index 6 months (R2 = .45, P = .011) post bariatric surgery. Conclusions Our results indicate that SG reduces plasma ET-1 levels, a possible mechanism for improved metabolic risk in these patients. These data also suggest that ET-1 may serve as a predictor of weight loss after bariatric surgery.

Background Opioid misuse occurs commonly among obese patients and after bariatric surgery. However, the risk of new persistent use following postbariatric body contouring procedures remains unknown. Methods The authors examined insurance claims from Clinformatics Data Mart (OptumInsight, Eden Prairie, Minn.) between 2001 and 2015 for opioid-naive patients undergoing five body contouring procedures: abdominoplasty/panniculectomy, breast reduction, mastopexy, brachioplasty, and thighplasty (n = 11,257). Their primary outcomes included both new persistent opioid use, defined as continued prescription fills between 90 and 180 days after surgery, and the prevalence of high-risk prescribing. They used multilevel logistic regression to assess the risk of new persistent use, adjusting for relevant covariates. Results In this cohort, 6.1 percent of previously opioid-naive patients developed new persistent use, and 12.9 percent were exposed to high-risk prescribing. New persistent use was higher in patients with high-risk prescribing (9.2 percent). New persistent use was highest after thighplasty (17.7 percent; 95 percent CI, 0.03 to 0.33). Increasing Charlson comorbidity indices (OR, 1.11; 95 percent CI, 1.05 to 1.17), mood disorders (OR, 1.27; 95 percent CI, 1.05 to 1.54), anxiety (OR, 1.41; 95 percent CI, 1.16 to 1.73), tobacco use (OR, 1.22; 95 percent CI, 1.00 to 1.49), neck pain (OR, 1.23; 95 percent CI, 1.04 to 1.46), arthritis (OR, 1.30; 95 percent CI, 1.08 to 1.58), and other pain disorders (OR, 1.36; 95 percent CI, 1.16 to 1.60) were independently associated with persistent use. Conclusions Similar to other elective procedures, 6 percent of opioid-naive patients developed persistent use, and 12 percent were exposed to high-risk prescribing practices. Plastic surgeons should remain aware of risk factors and offer opioid alternatives. Clinical question/level of evidence Risk, III.

Aims Applications to specialty training are falling and retention of trainees is increasingly challenging. Clinical placements influence students’ perceptions of a specialty and may impact on career choices. We evaluated medical students’ views of Paediatrics before and after their placement and explored the effect of a focused Careers Workshop. Methods A survey was distributed to medical students before (n=93) and after (n=74) their Child Heath block (Standard Group). Subsequently, a smaller group of students were invited to a Careers Workshop during their placement and surveyed before (n=20) and after (n=13) (Intervention Group). The workshop covered the ‘highs’ and ‘lows’ of working in Paediatrics as well as general careers advice, and a separate survey was completed to evaluate this (n=18). Results Paediatrics was a popular ‘Top 3’ careers option, second only to General Practice. Students reported that formal careers advice and clinical contact are both important for career planning. Positive perceptions of Paediatrics included working with children, clinical variety and being rewarding. Negative perceptions focused on emotional challenges, poor work-life balance and managing parents. After placement, the Intervention group were more likely to comment on the positive aspects of a ‘clinically varied’ and ‘rewarding’ workload. Following the Careers Workshop, 72% of students felt ‘well informed’ about careers in medicine generally and 94% regarding careers in Paediatrics. The workshop helped to address pre-conceptions regarding competition ratios and work-life balance. In both groups, students were more likely to consider Paediatric training following their placement, with interest increasing from 69% to 76% (Standard group) and 70% to 77% (Intervention group). Conclusion Our data demonstrates that clinical placements influence students’ perceptions of a specialty. Although the Careers Workshop improved knowledge of careers in Paediatrics, there was no measurable difference between groups in the overall number of students considering the specialty. Nevertheless, trainees and consultants should be aware of the importance of clinical placements in shaping students’ understanding and perceptions of a specialty. Careers advice should be integrated throughout the medical school curriculum and could run alongside clinical placements rather than as a separate entity.

BACKGROUND Ocular abnormalities in craniosynostosis are a persistent concern for patients and providers, and some surgeons feel that early surgical intervention for synostosis alleviates the progression of ophthalmologic abnormalities. In contradistinction, the authors hypothesize that operating early will have no bearing on postoperative ophthalmologic outcomes. METHODS Single-suture craniosynostosis patients who underwent surgical correction between 1989 and 2015 were reviewed. Patients with multisuture craniosynostosis, syndromic diagnoses, no preoperative ophthalmology evaluation, and less than 2 years of follow-up were excluded. Logistic regression was used to determine odds of preoperative and postoperative ophthalmologic abnormalities by age, while controlling for patient-level covariates. RESULTS One hundred seventy-two patients met inclusion criteria. The median age at surgery was 10 months (interquartile range, 7 to 12.9 months). Increasing age at the time of surgery was associated with increased odds of preoperative ophthalmologic diagnoses (OR, 1.06; p = 0.037) but not postoperative diagnoses (OR, 1.00; p = 0.91). Increasing age at surgery was also not associated with increased odds of ophthalmologic diagnoses, regardless of timing (OR, 1.04; p = 0.08). Patients with coronal synostosis (OR, 3.94; p = 0.036) had significantly higher odds of preoperative ophthalmologic diagnoses. Patients with metopic (OR, 5.60; p < 0.001) and coronal (OR, 7.13; p < 0.001) synostosis had significantly higher odds of postoperative ophthalmologic diagnoses. CONCLUSIONS After reviewing an expansive cohort, associations of both overall and postoperative ophthalmologic diagnoses with age at surgery were not found. The authors' findings thus run counter to the theory that early surgical intervention lessens the likelihood of postoperative ophthalmologic diagnoses and improves ophthalmologic outcomes. CLINICAL QUESTION/LEVEL OF EVIDENCE Risk, III.

Purpose The purpose of this paper is to examine bias among White raters against racial minority women seeking employment in fitness organizations. Design/methodology/approach The authors conducted a 2 (applicant perceived racial identity) × 2 (applicant race) × 2 (hiring directive) factorial design experiment, with participant rater gender serving as the within-subjects variable. Adults in the USA (n=238) who had or were currently working in the fitness industry participated in the study. Findings Results indicate that applicant presumed racial identity and rater gender had direct effects, while applicant presumed racial identity, applicant race and rater gender had interactive effects, as well. Originality/value Results show that perceived racial identity affects raters’ view of job applicants, and the pattern of findings varies among racial groups.

Background Obesity and insulin resistance are positively correlated with plasma endothelin-1 (ET-1) levels; however, the mechanisms leading to increased ET-1 are not understood. Similarly, the full physiological complexity of ET-1 has yet to be described, especially in obesity. To date, one of the best treatments available for morbid obesity is bariatric surgery to quickly reduce body fat and the factors associated with obesity-related disease; however, the effects of vertical sleeve gastrectomy (SG) on plasma ET-1 have not been described. Objectives To determine if SG will reduce plasma ET-1 levels and to determine if plasma ET-1 concentration is associated with weight loss after surgery. Setting The studies were undertaken at a University Hospital. Methods This was tested by measuring plasma ET-1 levels from 12 obese patients before and after SG. All data were collected from clinic visits before SG, 6 weeks after SG, and 6 months after surgery. Results At 6 weeks after SG, plasma ET-1 levels increased by 24%; however, after 6 months, there was a 27% decrease compared with presurgery. Average weight loss in this cohort was 11.3% ± 2.4% body weight after 6 weeks and 21.4% ± 5.7% body weight after 6 months. Interestingly, we observed an inverse relationship between baseline plasma ET-1 and percent body weight loss (R2 = .49, P = .01) and change in body mass index 6 months (R2 = .45, P = .011) post bariatric surgery. Conclusions Our results indicate that SG reduces plasma ET-1 levels, a possible mechanism for improved metabolic risk in these patients. These data also suggest that ET-1 may serve as a predictor of weight loss after bariatric surgery.

The measurements of magnetic hysteresis for aggregates of nanoparticles deposited on a surface are reported. Magnetite nanoparticles derived from magnetotactic bacteria are studied using nanomechanical torque magnetometry. The nanoparticles are deposited on high-stress Si3N4 membranes, to allow inspection by electron microscopy, followed by focused ion-beam milling of torsional resonators precisely located to capture selected aggregates within the membrane area. Torque magnetometry is performed using the resonators. We investigate also the magnetic torque-driven AC resonant modes of the modified supporting membrane. The observations are compared to numerical simulations of the mechanical modes, and to micromagnetic modeling of the hysteresis of a specific measured cluster of ∼350 nanoparticles.

Texas has the greatest installed wind turbine capacity of any state in the United States, but as the percentage of wind generation approaches 10% of the utilities total electrical generation (in 2012, the total wind generated electricity in Texas was 7.4%), it becomes increasingly difficult for the utility to balance the electrical load due to the mismatch between the wind farm (WF) generated electricity and the utility electrical loading. In this paper WF output was shown to be diurnally and seasonally mismatched with the utility electrical loading in the Texas Panhandle (e.g. Texas Panhandle has the highest wind energy resource in Texas). In addition, the wind farm output in the Texas Panhandle does not normally contribute significantly at the peak hourly electrical load, and the peak hourly electrical load is a major deciding factor for a utility to add new power plants. A financial analysis was also performed on all the renewable energy systems analyzed. Various ratios of wind farm output to concentrating solar power (CSP) parabolic trough plant output (with 6 h of thermal storage) were calculated for the Texas Panhandle and compared to the utility electrical loading on an annual and peak monthly basis (each renewable energy system was analyzed at a 100 MW rating). The 67 MW wind farm and the 33 MW CSP plant with 6 h of thermal storage was approximately the best match to the utility electrical loading. The utility electrical load was also compared to: a 100 MW WF, a 100 MW CSP plant (with and without 6 h thermal storage), and finally the 67 MW WF with 33 MW CSP plant (with 6 h of thermal storage) on an annual, monthly, and peak hourly load basis. Typically for each month, the wind farm did not match the utility electrical loading except in the evening while the CSP plant (without storage) matched the utility electrical loading with the exception of in the evening. For the peak utility electrical loading months (July and August) and the days with the peak electrical loadings during those months, the 100 MW CSP plant with 6 h of thermal storage performed best in terms of supporting the utility electrical load (e.g. no wind farm). For the Texas Panhandle the estimated levelized cost of energy (LCOE) of a hybrid WF/CSP plant was in the range of $108/MW h to $129/MW h while the WF only system was estimated to be $64/MW h, but the benefits of adding CSP may justify the additional cost. Although the Texas Panhandle was the only location analyzed for combining CSP plants with WFs, the analysis described in this paper can be used for other regions, states, or countries.

Controlling Magnetic Noise Ferromagnetic materials contain a number of magnetic domains, with individual domains switching stochastically as the field strength is increased. As magnetic memory elements shrink in size, it is important to understand, and ultimately control, this magnetic noise. Using a magnetic vortex core integrated with a nanomechanical torsion balance, Burgess et al. (p. 1051 , published online 17 January) created a two-dimensional map of the magnetic potential within the sample with nanoscale resolution. Moreover, introducing geometric defects (dimples) in the sample allowed the magnetization to be stabilized.

An optomechanical platform for magnetic resonance spectroscopy will be presented. The method relies on frequency mixing of orthogonal RF fields to yield a torque amplitude (arising from the transverse component of a precessing dipole moment, in analogy to magnetic resonance detection by electromagnetic induction) on a miniaturized resonant mechanical torsion sensor. In contrast to induction, the method is fully broadband and allows for simultaneous observation of the equilibrium net magnetic moment alongside the associated magnetization dynamics. To illustrate the method, comprehensive electron spin resonance spectra of a mesoscopic, single-crystal YIG disk at room temperature will be presented, along with situations where torque spectroscopy can offer complimentary information to existing magnetic resonance detection techniques. The authors are very grateful for support from NSERC, CRC, AITF, and NINT. Reference: Science 350, 798 (2015).

The objective of this paper was to determine if three different direct normal irradiance (DNI) models were sufficiently accurate to determine if concentrating solar power (CSP) plants could meet the utility electrical load. DNI data were measured at three different laboratories in the United States and compared with DNI calculated by three DNI models. In addition, utility electrical loading data were obtained for all three locations. The DNI models evaluated were: the Direct Insolation Simulation Code (DISC), DIRINT, and DIRINDEX. On an annual solar insolation (e.g. kW h/m2) basis, the accuracy of the DNI models at all three locations was within: 7% (DISC), 5% (DIRINT), and 3% (DIRINDEX). During the three highest electrical loading months at the three locations, the monthly accuracy varied from: 0% to 16% (DISC), 0% to 9% (DIRINT), and 0% to 8% (DIRINDEX). At one location different pyranometers were used to measure GHI, and the most expensive pyranometers did not improve the DNI model monthly accuracy. In lieu of actually measuring DNI, using the DIRINT model was felt to be sufficient for assessing whether to build a CSP plant at one location, but use of either the DIRINT or DIRINDEX models was felt to be marginal for the other two locations due to errors in modeling DNI for utility peak electrical loading days – especially for partly cloudy days.

While many remote water pumping systems exist (e.g. mechanical windmills, solar photovoltaic, wind-electric, diesel powered), few combine both the wind and solar energy resources to possibly improve the reliability and the performance of the system. In this paper, off-grid wind turbine (WT) and solar photovoltaic (PV) array water pumping systems were analyzed individually and combined as a hybrid system. The objectives were to determine: (1) advantages or disadvantages of using a hybrid system over using a WT or a solar PV array alone; (2) if the WT or solar PV array interfered with the output of the other; and (3) which hybrid system was the most efficient for the location. The WT used in the analysis was rated at 900 W alternating current (AC). There were three different solar PV arrays analyzed, and they were rated at 320, 480, and 640 W direct current (DC). A rectifier converted the 3-phase variable voltage AC output from the WT to DC before combining it with the solar PV array DC output. The combined renewable energies powered a single helical pump. The independent variable used in the hybrid WT/PV array analysis was in units of W/m 2 . The peak pump efficiency of the hybrid systems at Bushland, TX occurred for the 900 W WT combined with the 640 W PV array. The peak pump efficiencies at a 75 m pumping depth of the hybrid systems were: 47% (WT/320 W PV array), 51% (WT/480 W PV array), and 55% (WT/640 W PV array). Interference occurred between the WT and the different PV arrays (likely due to voltage mismatch between WT and PV array), but the least interference occurred for the WT/320 W PV array. This hybrid system pumped 28% more water during the greatest water demand month than the WT and PV systems would have pumped individually. An additional controller with a buck/boost converter is discussed at end of paper for improvement of the hybrid WT/PV array water pumping system.

Background About one-third of patients undergoing a Roux-en-Y anastomosis develop Roux stasis syndrome, likely because of disordered electrical conduction. GI electrical stimulation has been previously used successfully in the management of postsurgical gastroparesis. Objective Endoscopic placement of temporary electrodes and GI electrical stimulation in the management of severe Roux stasis syndrome in a patient with esophagojejunostomy and to determine whether the patient would be a candidate for surgical permanent electrode placement. Design Case report. Setting Academic medical center. Patients This study involved a patient with Roux stasis syndrome. Intervention Upper endoscopy was performed, followed by endoscopic placement of two temporary electrodes, one each in the two jejunal limbs. Electrical stimulation was provided by an external stimulation device. The patient was re-evaluated 5 days later. Main Outcome Measurements Electrogastrogram (EGG) parameters including frequency, amplitude, and frequency-amplitude ratio and total symptom score and health-related quality of life score. Results There was a significant improvement in EGG parameters with electrical stimulation. Also, the patient had a marked improvement in total GI symptom score, from 11 to 4, with a dramatic improvement in the health-related quality of life score from −3 to +3. Limitations Single case report. Conclusion Endoscopic placement of temporary electrodes is feasible and safe. GI electrical stimulation of the jejunal limb is a potentially effective treatment for Roux stasis syndrome.

For several years, many types of solar powered water pumping systems were evaluated, and in this paper, diaphragm and helical solar photovoltaic (PV) powered water pumping systems are discussed. Data were collected on diaphragm and helical pumps which were powered by different solar PV arrays at multiple pumping depths to determine the pumping performance, efficiency, and reliability of the different systems. The highest diaphragm pump hydraulic efficiency measured was ∼48%, and the highest helical pump hydraulic efficiency measured was ∼60%. The peak total system efficiency (e.g. solar radiation to pumped water) measured for the diaphragm and helical pumps were ∼5% and ∼7%, respectively (based on PV modules with ∼12% efficiency). The daily water volume of the three-chamber high head diaphragm pump performed better than the dual-chamber high head diaphragm pump (∼5 to ∼100% depending on PV array input power and pumping depth). Use of a controller was shown to improve the quad diaphragm pump performance below a solar irradiance of 600 W/m 2 (20 m head) to 800 W/m 2 (30 m head). While diaphragm pumps made mostly of plastic demonstrated similar to much better pumping performance than diaphragm pumps made with a high proportion of metal, the metal pumps demonstrated a longer service life (>2 years) than the plastic pumps service life (

Some small scale, off-grid irrigation systems (< 2.5 ha) that are powered by wind or solar energy are cost effective, but this article discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. It was found that partitioning the center pivot irrigation system between a winter crop and a summer crop improved the match of wind turbine power generation to irrigation energy required. It was also found that a solar-photovoltaic (PV) array was a better match to the irrigation energy requirement of a winter and summer crop than using only a wind turbine, but a wind/solar hybrid was a better match than wind alone. Although solar PV systems were shown to be a better match than wind turbines for irrigation power requirements, solar PV systems are more expensive than small wind turbine systems for large-scale irrigation water requirements in the Great Plains. Including on-farm uses for the excess wind and solar electricity instead of selling the electricity back to a utility company at usually low prices, improves the profitability of a renewable energy powered irrigation system significantly. For a utility electrical price of $0.10/kWh, a wind turbine installed price of $3000/kW, no loan required (e.g. no loan costs), and the excess renewable energy generated electricity used for on-farm use only, a payback period of seven to eight years was possible with no state or federal incentives. With 55% federal incentives and the same assumptions, a payback period of four to five years was possible. Also, if the assumed operations and maintenance costs doubled, the payback period increased about two years. However, cost reductions are still required for both wind and solar energy systems in order that renewable energy systems can be competitive without the need for state or federal incentives when loans at 90% of installed cost with a 6% interest rate are required.

Background: Genetic differences associated with individual's immune responses appear to be a major contributing factor to the development of trauma-induced sepsis. Thus, effective treatment of sepsis requires the identification of the patients who are at increased risk for sepsis. Methods: Sixty-eight patients, of which the majority had an injury severity score >15, and 118 controls from the same geographic region were genotyped. Cytokine and Toll-like receptor (TLR) genotypes and expressions were tested using polymerase chain reaction (PCR). Results: Fifty percent of African American and 42% of Caucasian patients developed posttrauma sepsis. Frequency distribution of the polymorphism for some cytokine genes such as Interleukin (IL)-10 low/high and interferon (IFN)-y low producer were statistically different between the septic and aseptic patients, for others, such as tumor necrosis factor (TNF)-a, IL-6, and IL-18, there was no statistical difference. The TLR-2 genotypes (A/G) were considered a sepsis risk marker as compared with A/A (62.5% versus 37.5%,p < 0.03; relative risk = 2.5) in African American patients. Cytokine mRNA levels correlated with genotype definition, particularly, for IL-10, IL-6, IL-18, and TNF-a. A time course study demonstrated a significant difference in cytokines expression profile in septic and aseptic patients before the development of sepsis. Conclusion: Monitoring cytokine expression levels before the disease might predict the outcome of sepsis. A large cohort study is needed to assess the diagnostic potential of the genotypes.

A simple decision-analysis model is used to determine the financial benefits accruing to one highway authority in Scotland from the use of weather radar imagery for u-inter-road-maintenance operations. Over a three-month period, the savings are some £23 000 greater than the benefits derived from the use of the particular OPEN ROAD forecast service employed by that authority.

Electrical conductivity measurements were performed on structurally anisotropic thin films deposited using the glancing angle deposition apparatus [K. Robbie and M. J. Brett, J. Vac. Sci. Technol. A 15, 1460 (1997); K. Robbie, J. Sit, and M. J. Brett, J. Vac. Sci. Technol. B 16, 1115 (1998); K. Robbie and M. J. Brett, US Patent No. 5,866,204 (2 February 1999)]. The films were comprised of bilayers of titanium over silica, engineered as a chevron morphology. Samples were evaporated at various incident vapor deposition angles α, in order to investigate the effects of morphology and voiding on the behavior of conductivity. A rapid decline in the conductivity, accompanied by an increase in conduction anisotropy in the plane of the substrate, was observed with increasing α. A random walk model was developed to model the transport properties of the films, and applied to microstructures predicted by a three-dimensional ballistic thin film simulator. In order to generate reasonable agreement between the modeling ...

A method of producing relatively monodisperse, small-diameter (sub-500 nm diameter) aerosol fibers is described. This method involves the separation of porous thin films from their substrate. It was found that fibers with diameters of less than several hundred nm and lengths of several micrometers can be formed that do not adhere to one-another. Two μ m thick columnar thin films were fabricated and processed, yielding aerosol fibers with lengths up to 2 μm and diameters up to 170 nm. Diameter and length distributions of a collected aerosol showed that a broad range of fiber lengths and diameters are formed by this method. Further modification of the method, however, is expected to greatly narrow the range of effective diameters and lengths obtained.

About 20 per cent of patients with carcinoma of the colon or rectum present with metastatic disease. Surgeons are frequently asked to consider resection or other operative procedures in these patients for palliation. We performed this review to determine whether patients presenting with known metastatic colorectal cancer derive benefit from surgical intervention. We performed a retrospective review of all patients with Ml carcinoma of the colon or rectum who were identified from the University of Mississippi Medical Center Cancer Registry from April 1985 through February 2003. Patients who underwent hepatic and/or pulmonary resection with curative intent were excluded from analysis, as were patients with metachronous metastases. Eighty patients with Ml colorectal cancer who did not undergo surgery with curative intent were identified, and in 74 of these, complete medical records and follow-up were available. Forty-nine of the 74 patients (66%) underwent an operation, and 25 were managed nonoperatively. Indications for surgery included bowel obstruction, active hemorrhage, severe anemia from gastrointestinal bleeding with requirement for blood transfusions, intractable pain, and perforation of the colon. Average survival was 11.2 months for operative patients versus 6.5 months for nonoperative patients ( P < 0.05). Thirty-six patients who underwent resectional procedures had a postoperative hospitalization of 7.5 days and a median survival of 11.5 months. Thirteen patients who had a nonresectional procedure had an average postoperative stay of 9 days and a median survival of 4 months. Median survival in those who did not undergo an operation was 4.8 months. Although metastatic colorectal carcinoma cannot usually be cured by surgical intervention, many patients who present with metastatic disease will benefit from palliative operations with relatively short hospitalizations and reasonable survival. Those who are not candidates for resection of the primary tumor have shorter survival times. Surgery can alleviate many of the distressing symptoms in patients with metastatic colorectal carcinoma.

Solar energy, wind energy, and a combination of wind and solar energy have been used successfully to power an UV (ultraviolet) water purification system. The main reason for this success has been the design of the controllers which have been operating for almost two years with various wind and solar energy inputs. Five different solar and wind energy systems have been tested so far and although these renewable energy systems have been used for water purification, graphs contained in the paper can be used to determine the feasibility of powering various other electrical loads. Combining a 100 Watt solar system with a 900 Watt wind turbine resulted in pumping and purifying enough water to satisfy the potable water requirements of 4000 people (16000 liters/day) at an estimated equipment cost of about $4660 (approximately $1/person).

Recent experimental work by a number of researchers has demonstrated that unusual high porosity thin films may be obtained in physical deposition systems by combining glancing angle deposition with in situ substrate motion control. The microstructure of these films consists of isolated columns engineered into shapes such as helices, posts, or chevrons. Due to the isolated nature of the columns, the films present a unique opportunity to study fundamental thin film growth behavior and, in particular, the influence of the self-shadowing mechanism in three dimensions. Apart from this academic motivation, there is the need to characterize the physical constraints imposed on the engineering of these films. In particular, this study will have implications for the realization of isolated, periodically arranged nanostructures envisioned for certain applications such as photonic band gap crystals. Results from an ongoing study of growth dynamics, morphology, porosity, and scaling behavior, and the dependence of these features on deposition parameters are presented.

The effectiveness of debris reduction using magnetically guided pulsed laser deposition (MGPLD) is reported here. KrF laser pulses (248 nm) of 100 mJ energy were focused to intensities of 6×109 W/cm2 onto the surface of a copper or a carbon source target and a magnetic field of 0.3 T as used to steer the plasma around a curved arc of 0.5 m length to the deposition substrate. Debris counts were compared for films produced by the MGPLD and conventional PLD (nonguided) techniques. A significant reduction in particulates of size greater than 0.1 μm was achieved using MGPLD. For the copper films, particulate count was reduced from 150 000 particles/cm2/nm to 50 particulates/cm2/nm and for diamond-like carbon thin films particulate count was reduced from 25 000 particles/cm2/nm to 1200 particles/cm2/nm.

We investigated the use of a novel class of porous thin films for the characterization of tapping mode atomic force microscope (AFM) tips. Chromium and titanium films were evaporated using the technique of glancing angle deposition (GLAD) onto rotating silicon substrates. The morphology of the resulting films consisted of isolated vertical posts of sub-micron size. These isolated topographical features are small enough to provide useful information about tip morphology and aid in assessing tip wear and damage. The films were imaged using an AFM, and previously published tip reconstruction algorithms were used to obtain three-dimensional tip functions. These compared well with envelope profiles determined from scanning electron microscope images of the tips.

A new approach is described in the deposition of thin films for thermal barrier applications. Using controlled substrate motion, porous layers and capping layers were vacuum deposited in an alternating fashion, creating a new, multilayered film structure. Direct measurements of the thermal properties of these multilayers were made using the 3ω and Mirage techniques. In the 3ω technique, heat is introduced into the coating by an AC current flowing through an evaporated resistor with a frequency ω. A fit of resistor voltage as a function of frequency yields the thermal conductivity. In the Mirage technique, an oscillating temperature is induced immediately above the film using a pulsed laser. A second probe laser aligned parallel to the surface is deflected by these temperature variations, and the thermal diffusivity is then found by fitting amplitude and phase shift data to the solution of the three-dimensional diffusion equation. Typically, the 3ω and Mirage techniques measure thermal constants in directions normal and parallel to the substrate, respectively. Measurements using these methods led to estimates of a reduction in thermal diffusivity of as little as 9% of that of films deposited entirely at normal incidence. Thermal simulations of similar structures also predicted a substantial decrease in overall thermal conductivity. In a specific case, an improved conductivity of 18% of that of films deposited by standard techniques was estimated.

Pulsed laser deposition (PLD) has been used together with the Glancing Angle Deposition (GLAD) technique [1,2] for the first time to produce highly porous structured films. A laser produced carbon plasma and vapour plume was deposited at a highly oblique incident angle onto rotating Si substrates, resulting in films exhibiting high bulk porosity and controlled columnar microstructure. By varying the substrate rotation rate, the shape of the microcolumns can be tailored. These results extend the versatility of the GLAD process to materials not readily deposited by means of traditional physical vapour deposition techniques.

It is well known that applying validation methods during product development will reduce product functionality problems. Generally, the earlier an error is found, the less it costs to resolve it. The traditional amount of validation analysis applied during the detailed design of derivative commercial airplanes is being challenged due to market pressures to cut costs. Without sufficient validation, a significant number of functional integration problems can remain undetected until discovered late in development by flight tests or during airline operations – which translates into cost overruns. A tradeoff exists between making planned investments in validation analysis and incurring unplanned costs later. Having the ability to identify where in the design to focus design validation analyses is essential for assuring a functionally integrated product and minimizing total development costs. A design-attribute risk assessment methodology based upon search theory, technical risk analysis concepts, and systems heuristics was developed and applied for this purpose.

The production of highly porous films by oblique deposition has attracted recent attention because of the possible applications of such films. The morphology of obliquely evaporated films is thought to be determined mainly by the mechanisms of self-shadowing and surface diffusion. The thin film process simulator GROFILMS has been used to verify the importance of these effects, and clarify some aspects of how they interact to determine the final film morphology. Good agreement between simulations and actual films has been achieved. Temperature control of the film during deposition is shown to be an important consideration for the production of structurally engineered films.

Recovery from alcoholism has typically involved the program of Alcoholics Anonymous (AA). However, the values espoused by AA, especially those related to spirituality, can be in conflict with the values of traditional Native Americans. This article discusses healing methods founded in the traditions of Native American culture in general and the Oglala Lakota (also called Oglala Sioux) nation specifically. An understanding of these methods gives non-Native American counselors additional tools for guiding Native American clients to an effective program of recovery.

The water pumping performance of two wind-electric systems is compared to the water pumping performance of two solar-PV systems. The wind-electric systems were rated at 1.0 kW and 1.5 kW at a wind speed of about 12 m/s, and the rotor diameters were 2.75 m and 3.05 m, respectively. The solar-PV systems were rated at 0.1 kW and 0.9 kW at a radiation level of about 1,000 W/m{sup 2}, and the total solar panel surface areas were 1 and 17 m{sup 2}, respectively. Both wind-electric systems powered three-phase 230 V a-c induction motors with centrifugal pumps. The smaller of the solar-PV systems powered a d-c motor with a diaphragm pump, and the larger one powered a single phase 230 V a-c induction motor with a centrifugal pump. Only a well pumping depth of 30 m was evaluated for both wind-electric and solar-PV water pumping systems. The 0.1 kW and the 0.9 kW solar water pumping systems can provide enough water for 25 and 75 cattle, respectively, if the incident solar radiation is similar to that of Bushland, TX. The 1.0 kW and 1.5 kW wind-electric water pumping systems can provide enough water for 300 and 400 cattle, respectively, if themore » wind regime is similar to that of Bushland, TX.« less

We report on the development of on-chip microcavities and show their potential as a platform for cavity quantum electrodynamics experiments. Microcavity arrays were formed by the controlled buckling of SiO2/Ta2O5 Bragg mirrors and exhibit a reflectance-limited finesse of 3500 and mode volumes as small as 35λ3. We show that the cavity resonance can be thermally tuned into alignment with the D2 transition of 87Rb and outline two methods for providing atom access to the cavity. Owing to their small mode volume and high finesse, these cavities exhibit single-atom cooperativities as high as C1=65. A unique feature of the buckled-dome architecture is that the strong-coupling parameter g0/κ is nearly independent of the cavity size. Furthermore, strong coupling should be achievable with only modest improvements in mirror reflectance, suggesting that these monolithic devices could provide a robust and scalable solution to the engineering of light-matter interfaces.

Since oral exposure is more relevant than the sc route for human exposure to environmental substances, studies to evaluate and standardize this route in the Hershberger assay were conducted in 2001–2003. Interest in environmental androgen agonists is increasing, so the oral route of the Hershberger assay may be useful to quantify agonist activity of these substances. Castrated Sprague–Dawley rats were dosed (PND 60–69) with androgen receptor agonists and/or antagonists, terminated on PND 70, and body, liver, and accessory sex organs (ASOs) weighed. Methyltestosterone (MT) po, at 0.1–50 mg/kg/day, resulted in dose-dependent increases in ASO weights at 5–50 mg/kg; 0.1 mg/kg/day was without statistically significant effect. Testosterone propionate (TP) (sc) at 0.1–1.6 mg/kg/day also resulted in dose-dependent increases in ASO weights, at all doses. Detection of putative androgen antagonists by the oral route was confirmed with dose–response curves of antagonism from flutamide (FLU) po at 1, 5, or 10 mg/kg/day, with MT at 5 or 10 mg/kg/day (po, 4 h later). These results extend the OECD Hershberger assay evaluation and standardization to the oral route and identify and discuss challenges of the assay to detect (anti)androgen-active compounds.

Here we report a new sample preparation method for three-dimensional electron tomography. The method uses the standard film deposition and focused ion beam (FIB) methods to significantly reduce the problems arising from the projected sample thickness at high tilt angles. The method can be used to prepare tomography samples that can be imaged up to a ±75° tilt range which is sufficient for many practical applications. The method can minimize the problem of Ga+ contamination, as compared to the case of FIB preparation of rod-shaped samples, and provides extended thin regions for standard 2D projection analyses. Microsc. Res. Tech. 75:1165–1169, 2012. © 2012 Wiley Periodicals, Inc.

MEMS based laser projection is of high interest for automotive head-up displays and dashboard displays, as well as for an increasing number of personal mobile projection applications. These applications require scanning mirrors that offer high scan frequencies and wide scan angles while showing low power consumption. This paper presents a novel low-power high-Q scanning mirror that is vacuum encapsulated on wafer level and thereby exhibits Q-factors exceeding 145,000. A new glass forming process enables fabrication of glass wafers with inclined 3D-shaped windows needed to spatially separate the direct reflex from the projected image.

The formation and evolution of collisional structures in the coronas of laser-produced plasmas have been studied by irradiating multilayered targets with nonuniform laser beams. Spatially resolved x-ray emission patterns and spectra were recorded to infer the temperatures, ionization states, and time-integrated hydrodynamic histories of plasmas originating from tracer layers embedded in the targets. The conditions of the experiment have been simulated using a two-dimensional single-fluid hydrodynamic code. The experimental results and code predictions are in good agreement, showing the stagnation of colliding plasmas in the nonirradiated regions

We demonstrate that the transition from the high-field state to the vortex state in a nanomagnetic disk shows the magnetic equivalent of supercooling. This is evidence that this magnetic transition can be described in terms of a modified Landau first-order phase transition. To accomplish this we have measured the bulk magnetization of single magnetic disks using nanomechanical torsional resonator torque magnetometry. This allows observation of single vortex creation events without averaging over an array of disks or over multiple runs., Comment: 11 pages preprint, 4 figures, accepted to New Journal of Physics

Thin films with microstructures controlled on a nanometer scale have been fabricated using a recently developed process called glancing angle deposition (GLAD) which combines oblique angle evaporation with controlled substrate motion. Critical to the production of GLAD thin films is the requirement for a narrow angular flux distribution centered at an oblique incidence angle. We report here recent work with low-pressure, long-throw sputter deposition with which we have succeeded in fabricating porous titanium thin films possessing “zig-zag,” helical, and “pillar” microstructures, demonstrating microstructural control on a level consistent with evaporated GLAD. The use of sputtering for GLAD simplifies process control and should enable deposition of a broader range of thin film materials.

Acoustical noise data have been collected and analyzed on small wind turbines used for water pumping at the USDA-ARS Conservation and Production Research Laboratory (CPRL) near Bushland, TX. This acoustical analysis differed from previous research in that the data were analyzed with rotor or tip speed being the independent variable in addition to analyzing the data with wind speed as the independent variable. Acoustical noise generation was analyzed for two different wind turbines which were tested with different blades. The averaging period for acoustical noise data was one second instead of one minute (smallest time increment recommended in IEC wind turbine noise standard) since the sound pressure level of small stand-alone wind turbines can vary significantly over just a few seconds. Disconnecting the wind turbine from the water pump motor by the pump controller was shown to significantly increase the noise of the wind turbine.

Recent developments in pumping technologies have allowed for efficient use of renewable energies like wind and solar to power new pumps for remote water pumping. A helical type, positive displacement pump was developed a few years ago and recently modified to accept input from a variable power source. This pump was tested at different pumping depths with both solar and wind energy power sources. The solar power source consisted of 640 W of photovoltaic panels and the wind power source was a 1000 W wind turbine. For Bushland, Texas, the solar powered pump provided enough water for the 150 beef cattle in the summer months of June, July, and August and was adequate in winter months when water consumption was lower. The wind powered pumping system provided sufficient water in summer for the same number of cattle (150 head), but had excess water in the winter and spring when winds were higher and water consumption was lower.

Purpose Surgical simulation modules for "open" surgery are limited and not well studied or validated. Available simulation modules use either synthetic material, which is convenient but may not mimic what is observed or felt in the operating room, or live animal laboratories, which can simulate human tissue but are costly and not readily available. An intestinal anastomosis simulation was devised with thawed porcine intestine. In this study, the face, content, and construct validities of this simulation module were analyzed for both hand-sewn and stapled anastomoses. Methods Participants were timed on performing a 2-layered, hand-sewn anastomosis, as well as a side-to-side, functional, end-to-end, stapled anastomosis on thawed porcine small bowel. Anastomoses were examined for adequacy and measured for luminal narrowing and bursting pressure by intraluminal saline infusion. Questionnaires were answered regarding impressions with the simulation modules. Face, content, and construct validities were evaluated by comparing junior residents to senior residents and faculty. Data collected were analyzed with 2-sample t -tests. Results Both hand-sewn and stapled anastomoses showed strong face and content validity. Overall impressions of these inanimate simulation modules were a positive experience as reflected by the comments of participants. For hand-sewn anastomoses, a significant difference was found between junior and senior group times (50.0 ± 17.2 vs 33.0 ± 9.7 minutes, p=0.013) as well as PGY-1 and faculty times (64.0 ± 7.2 vs 28.0 ± 3.8 minutes, p=0.001). Bursting pressures varied between both groups and were not significant. For stapled anastomoses, no difference was noted between the various groups in completion time or bursting pressure. Conclusions Hand-sewn and stapled inanimate intestinal anastomoses are a valid simulation of intraoperative experience based on the face and content validities. Although stapled anastomosis does not have good construct validity, the more challenging hand-sewn anastomosis does differentiate between various skill levels.