cssi/SciSciGPT-SciSciNet huggingface dataset:
Scuffing and wear behavior of aluminum piston skirt coatings against aluminum cylinder bore

Abstract Various coatings, especially nickel based ceramic composite (NCC) coatings, have been considered as an alternative to the use of iron plating on aluminum pistons in aluminum cylinder bore engines. Laboratory simulation tests were conducted to determine the scuffing and wear behavior of piston coatings against 390 Al engine cylinder bore. The tested piston coatings included nickel–tungsten (Ni–W) plating, electroless Ni plating, Ni–P coatings with ceramic particles such as boron nitride (BN), SiC, or Si 3 N 4 , as well as titanium nitride physical vapor deposition (PVD) coating, diamond-like carbon (DLC) coating, and hard anodizing. The scuffing and wear resistances of these coatings were evaluated and compared with tin plating and iron plating. Wear tests were performed in lubricated sliding at 400 K, using a modified Cameron Plint High Frequency test machine with a special fixture to hold the piston samples. Scuffing tests were conducted under the conditions in which lubricant starvation occurred. Metallographical work and chemical analysis of the interactive surface layers were performed on the tested samples. The simulation test results ranked the relative performance of the coatings against 390 Al bore, and revealed their tribological characteristics. Ni–P–BN coating, iron plating and Ni–W plating showed very good scuffing resistance when sliding against 390 Al bore samples. DLC, electroless Ni plating and Ni–P–SiC coating had moderate scuffing resistance against 390 Al. Ni–P–Si 3 N 4 and TiN coatings had marginal scuffing resistance against 390 Al. TiN PVD coating had the most severe wear on 390 Al bore samples. Hard anodizing, DLC, Ni–P–SiC and Ni–Si 3 N 4 coatings had less severe wear on 390 Al than TiN coating. With very good wear resistance themselves, Ni–W plating, electroless Ni plating, iron plating and Ni–P–BN coating produced the least wear on 390 Al. Engine dynamometer tests were conducted to confirm the simulation test results. This work indicates that the scuffing and wear bench simulation tests can be used as a rapid, low-cost and repeatable means of screening and studying the tribological behavior of the potential material combinations of piston coatings and cylinder bores.
A randomized study of ciprofloxacin versus ceftriaxone in the treatment of nursing home-acquired lower respiratory tract infections.

Objective: To compare the efficacy and safety of ciprofloxacin and ceftriaxone in patients with nursing home-acquired lower respiratory tract infections requiring initial hospitalization. Design: Prospective, randomized trial. Setting: Extended care nursing homes affiliated with a teaching hospital. Patients: Fifty patients aged 60 years or older with normal or mildly impaired renal function admitted to the hospital for treatment of lower respiratory tract infections. Interventions: Twenty-four patients received initial therapy with intravenous ciprofloxacin, 200 mg every 12 hours (19 patients) or 400 mg every 12 hours (5 patients) during the acute phase followed by 750 mg orally every 12 hours during the convalescence phase. Twenty-six patients received initial therapy with intravenous ceftriaxone, 2 g every 24 hours during the acute phase followed by 1 g administered intramuscularly every 24 hours during the convalescent phase. The total duration of therapy was 14 days. Main Outcome Measurements: Successful outcome was defined as resolution or marked improvement in clinical signs and symptoms of lower respiratory tract infection upon completion of the treatment course. Results: Twelve (50%) of the ciprofloxacin-treated and 14 (54%) of ceftriaxone-treated patients had successful outcomes. Recurrent oropharyngeal aspiration was the reason for treatment failure in most patients refractory to either antibiotic. Mortality during therapy was 8% in each group. From 21 satisfactory sputum specimens collected, S. pneumoniae was the most common isolate, followed by H. influenzae and other Gram-negative bacteria. Ciprofloxacin therapy was well tolerated; ceftriaxone therapy was discontinued in two patients (8%) due to adverse reactions (intramuscular pain and drug fever). Conclusions: Sequential intravenous/oral ciprofloxacin appears to be as safe and effective as sequential intravenous/intramuscular ceftriaxone. The optimal dosage of intravenous ciprofloxacin in this patient population appears to be 400 mg every 12 hours; however, additional clinical and pharmacokinetic studies with this regimen are warranted.
A Single‐Step Reaction for Silicon and Germanium Nanorods

A single-step reaction has been developed for colloidal quantum-size silicon (Si) and germanium (Ge) nanorods. The nanorods are formed by solution-liquid-solid (SLS) growth from tin (Sn) seed particles prepared by in situ reduction of a molecular tin(II) complex by trisilane, the reactant for Si nanorod growth. Using the same procedure, Ge nanorods can be grown by including a diphenyl germane reactant. The nanorod length could be adjusted from several nanometers to more than a micrometer without significant increase of diameter by manipulating reactant concentrations.
Transference of computerized irrigation cost budget generator: the Nevada experience.

Abstract With increasing energy costs, declining groundwater resources, and/or decreases in pumping plant efficiencies, irrigated producers have become more interested in their pumping costs. An effective method for analyzing irrigation costs is through the Oklahoma State University (OSU) computerized irrigation cost budget generator. However, when other land grant institutions attempted to use the OSU irrigation cost generator on their computers, the issue of computer program transferability arose. A discussion of the transfer problems of the OSU irrigation cost budget generator and the use of microcomputers to transfer the OSU algorithm are also presented.
Fields of action: Structure in movements' tactical repertoires

The structure of choice among available tactics is a key to understanding the roles of individuals and organizations within a social movement. This paper proposes a method for operationalizing the notion of repertoires of collective action. Using data from a case study of a recent disarmament campaign, it models the tactical field faced by activists. An analysis of the dimensions of this field and the clusters of tactics within it suggests how individuals organized their options and how they understood the distinctive features of an innovative course of action. Such field models can illuminate ideological and organizational differentiation, as well as cooperation and competition within movements.
Milling value of sorghums compared by adjusting yields to a constant product color.

ABSTRACT A method of comparing milling values of sorghum by adjusting yields to standard L values was developed. The milling values of ‘Dorado’ (an excellent food-type sorghum variety), ‘ATx399 × RTx430’ (a commercial red sorghum hybrid) and three ‘Warner 902W’ (commercial white food type hybrids with different levels of weathering designated W-1, W-2, and W-3) were determined using a tangential abrasive dehulling device for various times. Color (L, a, b) was measured on the decorticated grain (grits) and the ground grits (flour). The yields (by weight) of flours adjusted to an L value of 85 were 93, 88, 86, 84, and 70% for Dorado, W-2, W-1, W-3, and red, respectively. The b (yellow) values were highest for red and lowest for Dorado. The grits yields were 96, 89, 84.5, 81.5, and 56.5% when adjusted to an L of 67 for Dorado, W-2, W-1, W-3, and red sorghums, respectively. Milling yields expressed at comparable flour or grit color clearly demonstrate that white food-type sorghums have significantly better mi...
Food Characteristics of Recipes Using Stevia Sweetner - A Proposed Herbal Sugar Substitute

Abstract Stevia rebaudiana is a perennial herb with claimed medicinal and culinary characteristics. It is approximately 300 times sweeter than sucrose (table sugar). Thirty-two volunteer participants evaluated three different food products for the following sensory characteristics:.tenderness, aroma, color, grain size or consistency, and overall appearance. Standard food testing evaluation methods were used, including ink prints and standing height measurements. Data was analyzed using SPSS Data Software. Mean scores for each of the product characteristics were tested for individual significant differences (P=0.05) using the Friedman Test. In two out of the three products evaluated, recipes using 100% stevia and recipes using 25%sucrose/75%stevia ranked superior in four of five sensory characteristics evaluated (tenderness, aroma, color, grain size or consistency, and overall appearance). However, the type of food product appeared to influence overall evaluation scores. Low sugar diets are used in medical nutrition therapy (MNT) for diabetes, obesity, hyperglycemia, hyperlipidemia, and for the prevention of tooth decay. There is a demand in society for more sugar substitutes in cooked food products. Aspartame (Nutrasweet) disintegrates at higher temperatures and loses its sweetening ability. Likewise, saccharin has limited accessibility because of certain Food and Drug Administration (PDA) restrictions. Study results show that stevia can replace some or all of the sugar (sucrose) in recipes without drastically affecting the visual acceptability or physical characteristics of the food product. Therefore, further studies on the safety of stevia are needed to determine its potential usefulness as a sugar substitute.
Antimalarial Compounds from Rhaphidophora decursiva

Bioassay-directed fractionation led to the isolation of 14 compounds, six of which possess antimalarial activity, from the dried leaves and stems of Rhaphidophora decursiva. Polysyphorin (1) and rh...
A review of empirical flame impingement heat transfer correlations

Abstract Impinging flames are used in industrial heating and melting, safety research, and aerospace applications. Multiple modes of heat transfer are commonly important in those processes. However, the detailed heat transfer mechanisms are not well understood. The available semianalytical heat transfer solutions have only limited applicability. Therefore, researchers and designers have either made measurements or used empirical correlations to determine the heat flux rates. Here, the empirical correlations are reviewed. The correlations are first arranged by the flow geometry. Four geometries have been studied. These include flames impinging: (1) normal to cylinders in cross-flow; (2) normal to hemispherically nosed cylinders; (3) normal to plane surfaces; and (4) along plane surfaces. The correlations are then arranged by the size of the region on the target under consideration. Correlations that apply to a small region on the target, such as the stagnation point, are referred to as the local heat flux. Correlations that apply to a large region of the target, such as the entire body of a cylindrical target, are referred to as the average heat flux. Next, the correlations are arranged by the type of heat transfer. Correlations for natural and forced convection, thermochemical heat release (TCHR), radiation, forced convection with TCHR, and forced convection with radiation have been reported for some combinations of geometry and operating conditions. Finally, the correlations are arranged by the flow type, either laminar or turbulent. Correlations do not exist for many combinations of geometry and operating conditions; therefore, recommendations are given for further research.
Impact of emissions from shipping, land, and the ocean on stratocumulus cloud water elemental composition during the 2011 E-PEACE field campaign

This study reports on cloud water chemical and pH measurements off the California coast during the July–August 2011 Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE). Eighty two cloud water samples were collected by a slotted-rod cloud water collector protruding above the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter in boundary layer stratocumulus clouds impacted to varying degrees by ocean-derived emissions, ship exhaust, and land emissions. Cloud water pH ranged between 2.92 and 7.58, with an average of 4.46. Peak pH values were observed north of San Francisco, simultaneous with the highest concentrations of Si, B, and Cs, and air masses originating over land. The lowest pH values were observed south of San Francisco due to ship emissions resulting in the highest concentrations of sulfate, nitrate, V, Fe, Al, P, Cd, Ti, Sb, P, and Mn. Many of these species act as important agents in aqueous-phase reactions in cloud drops and are critical ocean micronutrients after subsequent wet deposition in an ocean system that can be nutrient-limited. E-PEACE measurements suggest that conditions in the California coastal zone region can promote the conversion of micronutrients to more soluble forms, if they are not already, due to acidic cloud water conditions, the ubiquity of important organic agents such as oxalic acid, and the persistence of stratocumulus clouds to allow for continuous cloud processing.
Osteopontin expression is essential for interferon-α production by plasmacytoid dendritic cells

The observation that the T-bet transcription factor allows tissue-specific upregulation of intracellular osteopontin (Opn-i) in plasmacytoid dendritic cells (pDCs) suggests that Opn might contribute to the expression of interferon-α (IFN-α) in those cells. Here we show that Opn deficiency substantially reduced Toll-like receptor 9 (TLR9)–dependent IFN-α responses but spared expression of transcription factor NF-κB–dependent proinflammatory cytokines. Shortly after TLR9 engagement, colocalization of Opn-i and the adaptor molecule MyD88 was associated with induction of transcription factor IRF7–dependent IFN-α gene expression, whereas deficient expression of Opn-i was associated with defective nuclear translocation of IRF7 in pDCs. The importance of the Opn–IFN-α pathway was emphasized by its essential involvement in cross-presentation in vitro and in anti–herpes simplex virus 1 IFN-α response in vivo. The finding that Opn-i selectively coupled TLR9 signaling to expression of IFN-α but not to that of other proinflammatory cytokines provides new molecular insight into the biology of pDCs.
Endwall driven, low prandtl number convection in a shallow rectangular cavity

Abstract This paper presents results from laboratory experiments on the oscillatory behavior of the flow of mercury enclosed in shallow, rectangular boxes with horizontal temperature gradients imposed. Emphasis has been placed on the effect that finite width of the chamber has on various observables. These observables include the critical Grashof number for the onset of oscillations, hysteretic effects, the spatial form of the instability, and its behavior at supercritical conditions. The first oscillatory instabilities to appear are in the form of standing, longitudinal waves (axis of the roll(s) perpendicular to the heated endwalls). For certain supercritical conditions, these instabilities generate subharmonic oscillations. As the temperature difference is increased beyond these regimes, the response becomes chaotic.
Repair of ventricular septal defects.

Primary closure of large ventricular septal defects was performed in 57 patients ranging in age from 1 to 24 months during an 11-year period. Weight of patients ranged from 2.5 to 12.2 kg (mean, 6.6±0.9 kg). Shunt flow was large with mean Qp/Qs, 3.5±0.5. It was possible to close the defect by the transatrial approach in 86% of patients using a prosthetic patch attached to the ventricular septum by continuous polypropylene suture (89%). Early mortality of 5% and late mortality of 2% and excellent functional results in 93% suggest that this approach is appropriate.
Rationale and Staff Evaluation of Using a “Therapeutic Milieu” for Substance Users Within a Tuberculosis Ward

Approximately 30% of tuberculosis (TB) patients in Israel were treated, in part, in two dedicated hospital wards during the years 2003–2005. A portion of them manifested severe psychosocial conditions. An intervention based on the “Therapeutic Milieu” (TM) model was implemented in the larger ward and included a staff evaluation of this intervention. The concept of TM, based on psychosocial paradigms and behavioral medicine, is aimed at providing a supportive environment for patients. Weekly group patients' meetings and monthly group staff supervisions were performed during 15 months (2003–2005). Forty of the 196 (20%) TB patients, mainly “complex,” and 13 of 20 staff members (65%) attended regularly and discussed how to deal with substance abuse, personality disorders, and immigration-related crises. Out of 40 TB cases, 30 (75%) were also substance users. Ten staff members self-analyzed the impact of this intervention in terms of (1) having given adequate tools for the staff, (2) reducing physical violenc...
The Rad50 hook domain is a critical determinant of Mre11 complex functions.

The Mre11 complex (in Saccharomyces cerevisiae: Mre11, Rad50 and Xrs2) influences multiple facets of chromosome break metabolism. A conserved feature of the Mre11 complex is a zinc-coordinating motif in Rad50 called the Rad50 hook. We established a diploid yeast strain, rad50hook, in which Rad50 is encoded in halves, one from each of the two RAD50 alleles, with the residues constituting the hook deleted. In all respects, rad50hook phenocopies complete Rad50 deficiency. Replacing the hook domain with a ligand-inducible FKBP dimerization cassette partially mitigated all phenotypes in a ligand-dependent manner. The data indicate that the Rad50 hook is critical for Mre11 complex–dependent DNA repair, telomere maintenance and meiotic double-strand break formation. Sister chromatid cohesion was unaffected by Rad50 deficiency, suggesting that molecular bridging required for recombinational DNA repair is qualitatively distinct from cohesin-mediated sister chromatid cohesion.
Sickle Cell Disease in Pregnancy

The term sickle cell disease (SSD) encompasses several different sickle hemoglobinopathies. The ability to predict the clinical course of SSD during pregnancy is difficult. This article examines pregnancy-associated complications in SSD and the management of sickle cell disorders in pregnant women. Outcomes have improved for pregnant women with SSD and nowadays the majority can achieve a successful live birth. However, pregnancy is still associated with an increased incidence of morbidity and mortality. Optimal management during pregnancy should be directed at preventing pain crises, chronic organ damage, optimization of fetal health and minimizing early maternal mortality using a multidisciplinary team approach and prompt, effective and safe relief of acute pain episodes.
Follow-up of aortic dissection: contribution of MR angiography for evaluation of the abdominal aorta and its branches

Spin-echo MR is an established method to evaluate thoracic aortic dissections, but is not well suited to study the abdominal aorta. In this study we evaluated whether MR angiography could provide a complete examination of the abdominal aorta. In 28 patients (40 MR studies) with suspected (n = 6) or known (n = 34) aortic dissection, MR studies were performed. Thoracic aorta was evaluated with spin-echo and gradient-recalled-echo MR imaging. Axial two-dimensional time-of-flight MR angiography with thin overlapping slices was used to study the abdominal aorta. Intermediate and high signal intensity on MR angiography was interpreted as patent flow, and low signal was interpreted as thrombus. The presence of an intima flap and the re-entry site could be depicted in all MR studies. Thrombus in the false channel was seen in 8 studies. The origin of the abdominal visceral branches and their relation to the false-true channel could be depicted, except in 4 of 80 renal arteries studied. Extension of the dissection into the coeliac trunk was seen in 2 and in the superior mesenteric artery in 10 studies. Dilatation of the suprarenal abdominal aorta was seen in 20 studies, and of the infrarenal aorta in 9 studies. MR angiography provides valuable information about the abdominal aorta and its branches in patients with aortic dissection. This makes MR imaging appealing as the preferred imaging modality for the diagnosis and follow-up of aortic dissection.
Elastostatic problems of curvilinear cracks in bonded dissimilar materials

Abstract Boundary problems for a circular elastic insert bonded partially to the interior of an infinite medium of another material are formulated and solved in closed form. The unbonded portions of the interface may be regarded as circular arcs of discontinuities or curved cracks. By application of the complex function theory dealing with sectionally holomorphic functions, the present problem is reduced to the solution of the problem of linear relationship or Hilbert problem. Exact solutions to several examples of theoretical and practical importance are obtained. They include the cases of uni-axial tension applied at infinity and concentrated forces located in the insert and/or the surrounding material. Contact stresses are computed and compared to those for perfect bonding. It is found that the stresses near the tips of a curved crack possess the same trig-log character of singularity as those obtained for a straight crack between dissimilar media. Formulas for finding the crack-tip stress-intensity factors, employed m the Griffith-Irwin theory of fracture, are also derived.
The metal-metal oxide interface: A study of thermally-activated diffusion at the Ni/Al2O3 interface using electron spectroscopies

The behavior of Ni atoms deposited on well-characterized Al2O3 films, prepared by oxidizing an atomically clean Al(111) surface, has been studied using high-resolution electron energy loss spectroscopy (EELS) and Auger electron spectroscopy (AES). At 200 K, the deposited Ni forms three-dimensional Ni clusters on the Al2O3/Al(111) substrate. Interaction of these Ni metal clusters with surface Al-O species is directly detected by observation of the preferential modification of surface phonon mode frequencies and intensities in contrast to the behavior of a bulk phonon mode of the Al2O3 substrate. Heating the Ni/Al2O3 deposit above 200 K gives rise to two thermally induced processes: Process, I, smoothing (below ∼400 K) of the three-dimensional Ni clusters and Process II, diffusion (400–700 K) of the Ni overlayer through channels in the Al2O3 film. The metallic aluminum beneath the Al2O3 film is found to provide a major driving force for the inward diffusion of the Ni overlayer by Ni-Al alloy formation. This work represents the first application of EELS to the study of transport processes in a thin film system.
Behavior of runoff-derived metals in a detention pond system

The removal and fate of runoff-derived heavy metals in a 1-yr old detention pond system were investigated during climatic conditions typical of the U.S. maritime Northwest. The catchment was a medium-sized, suburban parking lot near Portland, Oregon. Water samples from runoff, the detention pond system, and pond effluent were collected and analyzed for dissolved and particulate Cu. Copper was the dominant toxic metal for the study site, while analysis of selected samples for Pb and Cd showed these metals to be minor pollutants. Total Cu in runoff varied among different storm events over a wide range of concentrations (< 2 to 33 µg L−1), while total Cu levels in pond effluent remained within a fairly narrow range (5 to 12 µg L−1), Sediment samples collected from the detention pond system were analyzed for Cu in two size fractions (< 63 µm and < 125 µm). Copper was found to be deposited in the pond sediments in a small but highly concentrated plume (up to 130 mg kg−1), extending axially from the runoff inlet pipe. Overall, results from this study showed that low-cost, small-scale detention ponds can be a useful management practice for runoff from parking lot areas and can be of value in preserving the integrity of receiving waters.
The economic impact of a multifactorial intervention to improve postoperative rehabilitation of hip fracture patients

Objective To assess the cost savings associated with a patient education and high-intensity strength intervention to improve rehabilitation after hip fracture. Methods Economic analysis conducted alongside a randomized controlled trial, using cost-benefit ratios and net present value statistics. Study subjects were aged over 64 years and were followed for 18 months postsurgery. Resource utilization data were gathered by telephone questionnaire. Medicare reimbursement rates and prevailing costs for services not covered by Medicare were used to convert utilization patterns into costs. Intervention costs were obtained from program records. Results The cost of the intervention was $722 per patient. Over the followup period, median costs were $11,941 and $21,577 for the intervention and control groups, respectively, yielding an average program benefit of $9,636. Cost-benefit ratios exceeded 4.5, and net present value exceeded $150,974. Conclusion The results indicate that the benefits of the intervention exceeded its costs.
Determination of prednisolone in human adipose tissue incubation medium using LC-MS/MS to support the measurement of 11β-hydroxysteroid dehydrogenase activity

A method for the determination of prednisolone in human adipose tissue incubation medium has been developed, validated and used to support studies designed to measure the activity of 11beta-hydroxysteroid dehydrogenase in human adipose tissue. After incubation, samples (80 microL) were extracted using Oasis HLB microElute SPE plates and the resulting extracts were analyzed using reversed-phase chromatography coupled to an Applied Biosystems Sciex PE API-4000 mass spectrometer with a TurboIonSpray interface (400 degrees C). The method was validated over the calibration range of 0.5-100 ng/mL. Intraday precision and accuracy were 6.1% R.S.D. or less and within 6.3%, respectively. Interday precision and accuracy were 4.2% R.S.D. or less and within 3.6%, respectively. Extraction recovery of prednisolone was greater than 84% over the range of low to high quality control sample concentrations. The validated assay was used to support studies designed to estimate ex vivo 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) enzyme activity in human adipose tissue.
In situ evaluation of nearshore marine and fresh pore water transport into Flamengo Bay, Brazil

Abstract Transport between pore waters and overlying surface waters of Flamengo Bay near Ubatuba, Brazil, was quantified using natural and artificial geochemical tracers, 222Rn, Cl−, and SF6, collected from multi-level piezometers installed along a transect perpendicular to the shore. Eight sampling ports positioned along the length of the piezometers allowed sampling of pore waters at discrete depth intervals from 10 to 230 cmbsf (centimeters below seafloor). Small volume samples were collected from the piezometers using a peristaltic pump to obtain pore water depth profiles. Pore water 222Rn is deficient in shallow sediments, allowing application of a diffusion-corrected 222Rn exchange rate. This model estimates the magnitude of pore water exchange rates to be about 130–419 cm/day. An SF6-saturated fluorescein dye tracer was gently pumped into deep pore waters and exchange rates estimated from this method range from 29 to 185 cm/day. While absolute rates are higher using 222Rn than SF6, rates are of similar magnitudes and the trends with distance from shore are the same – flow is greatest 6 m from shore and decreases by more than 50% further offshore. A Cl− mass balance indicates the greatest fraction of fresh SGD occurs along an apparent preferential flow path in sediments within 5–7 m of the shoreline (87%). Recirculating bay waters through sediments dominate pore water advection at 10 m offshore where only 4% of the flow can be attributed to a freshwater source. Both fresh and marine sources combine to make up submarine groundwater discharge to coastal water bodies. The magnitude of fresh aquifer discharge is often a spatially variable and minor component of the total discharge.
Coordinated vs. independent inventory replenishment policies for a vendor and multiple buyers

Abstract Through a series of simulation experiments we show that classical lot sizing models do not adequately describe a situation where a single vendor produces and supplies a product to multiple industrial customers, buying in discrete lots. We suggest a common replenishment cycle based, coordinated inventory control model and show that this approach is superior to independent optimization.
Nissen fundoplication for gastroesophageal reflux disease in infants and children.

GASTROESOPHAGEAL reflux disease (GERD) is one of the most common symptomatic clinical disorders affecting the gastrointestinal tract of infants and children. Gastroesophageal fundoplication currently is one of the three most common major operations performed on infants and children by pediatric surgeons in the United States. For infants and children who do not show improvement from symptomatic GERD with medical management, or who have failure to thrive or recurrent pulmonary symptoms, fundoplication is recommended. It is my view, and that of many other pediatric surgeons, that most children with neurological impairment who require a feeding gastrostomy will benefit from concomitant gastroesophageal fundoplication. The isotope solid-meal gastric emptying study, appropriate for age, is the most accurate and reliable method for identifying abnormal gastric emptying, and we believe it should be performed on almost all children scheduled to undergo gastroesophageal fundoplication.
Optimal collision avoidance trajectories for unmanned/remotely piloted aircraft

Abstract : The post-911 environment has punctuated the force-multiplying capabilities that Remotely Piloted Aircraft (RPA) provides combatant commanders at all echelons on the battlefield. Not only have unmanned aircraft systems made near-revolutionary impacts on the battlefield, their utility and proliferation in law enforcement, homeland security, humanitarian operations, and commercial applications have likewise increased at a rapid rate. As such, under the Federal Aviation Administration (FAA) Modernization and Reform Act of 2012, the United States Congress tasked the FAA to provide for the safe integration of civil unmanned aircraft systems into the national airspace system (NAS) as soon as practicable, but not later than September 30, 2015. However, a necessary entrance criterion to operate RPAs in the NAS is the ability to Sense and Avoid (SAA) both cooperative and noncooperative air traffic to attain a target level of safety as a traditional manned aircraft platform. The goal of this research effort is twofold: First, develop techniques for calculating optimal avoidance trajectories, and second, develop techniques for estimating an intruder aircraft's trajectory in a stochastic environment. This dissertation describes the optimal control problem associated with SAA and uses a direct orthogonal collocation method to solve this problem and then analyzes these results for different collision avoidance scenarios.
Agonist-promoted Ubiquitination of the G Protein-coupled Receptor CXCR4 Mediates Lysosomal Sorting

Ligand-induced trafficking plays an important role in the physiologic regulation of many G protein-coupled receptors (GPCRs). Although numerous GPCRs are sorted to a degradative pathway upon prolonged stimulation, the molecular events leading to degradation are poorly understood. Here we report that the human immunodeficiency virus co-receptor CXCR4 undergoes rapid agonist-promoted degradation by a process involving endocytosis via clathrin-coated pits and subsequent sorting to lysosomes. Studies analyzing the sorting of various CXCR4 mutants revealed the presence of a degradation motif (SSLKILSKGK) in the carboxyl terminus of CXCR4. The first two serines as well as the dileucine motif were critical for agonist-induced endocytosis, whereas all three serines but not the dileucine were important in mediating degradation. Mutation of the three lysine residues had no effect on CXCR4 endocytosis yet completely inhibited receptor degradation. Because lysine residues represent potential sites of ubiquitination, we also examined the ubiquitination of CXCR4. Interestingly, CXCR4 was shown to undergo rapid agonist-promoted ubiquitination that was attenuated by mutation of the lysine residues within the degradation motif. These studies implicate a specific role for ubiquitination in sorting endocytosed GPCRs to lysosomes.
Locally complex distortions of the energy spectrum in the calculation of scattering amplitudes and photoionization cross sections

We demonstrate that the array of techniques employing complex basis functions, which have been broadly applied in the calculation of resonance positions and lifetimes, can also be used, with appropriate modification, in the practical computation of photoionization cross sections and nonresonant scattering amplitudes. We illustrate a procedure with which controlled complex distortions over a localized region of the energy spectrum can be realized in a finite basis-set calculation. This technique is used to directly obtain scattering amplitudes for potentials which are not exponentially bounded at large distances, in contrast to complex scaling techniques which have been shown to be divergent in such cases. Four numerical examples are presented to exhibit the utility of the local complex distortion approach in calculations of photoionization cross sections and scattering amplitudes. We also discuss this approach in the context of variational principles for continuum amplitudes and in the context of applications to many-electron systems.
Performance Measurement and Dysfunction: The Dark Side of Quantifying Work

(2002). Performance Measurement and Dysfunction. Public Performance & Management Review: Vol. 25, No. 4, pp. 363-369.
Feedbacks between flow, sediment motion and microbial growth on sand bars initiate and shape elongated stromatolite mounds

Abstract Elongated stromatolites are often used as indicators of current direction and shoreline orientation, especially in paleoenvironmental reconstructions. However, mechanisms that create shore-parallel, m-scale elongated stromatolite mounds in carbonate sand are not well understood. We propose that this geometry is initiated by microbial growth on the parts of sand bars that experience low wave-induced bed shear stresses. We test this idea by growing microbial mats on carbonate sand bars in a laboratory wave tank. Cyanobacterial mats grow on the bar runnels, where sediment motion is negligible, but are absent from the bar ridges, where the waves generate migrating ripples. When microbially-promoted lithification reinforces and preserves this initial pattern, elongated stromatolites should initiate in the runnels of sand bars, with long wavelengths (5–100 m) and small width-to-wavelength ratios (∼0.3). These dimensions are consistent with modern shore-parallel stromatolites in Hamelin Pool, Western Australia, and with patterns of microbial colonization in other sandy sediments. This model of elongated stromatolite mounds can inform paleoenvironmental reconstructions by clarifying and quantifying feedbacks among waves, sediment transport and microbial growth.
Scopolamine depresses play fighting: A replication

The effects of scopolamine and methylscopolamine (0.125—1.0 mg/kg) on play fighting by juvenile rats were compared. At doses of 0.25 mg/kg or higher, the centrally active anticholinergic, scopolamine hydrobromide, depressed pinning and reduced the total duration of play fighting. In contrast, scopolamine methylbromide had no effect. Neither drug reliably affected social investigation or rearing.
Preserving electronic documents

Electronic documents have many advantages, but they also have the serious disadvantages. One of them is difficulty in preservation. A method should be developed for preserving electronic documents in their original form that is independent of the hardware or software standards used.
Distribution of the largest neuron in mouse caudate-putamen nucleus: Its position in large-cell — Medium-cell clusters

The position of the largest striatal neuron within territories delimited by medium-sized clustered neurons was charted in Nissl-stained sections through the mouse caudate-putamen nucleus. Medium-sized neuron somata occur in close proximity to this large cell at some point in the anteroposterior, mediolateral or dorsoventral extent of its soma. The size of the network of medium-sized neurons associated with the large cell may vary from two to 15 neurons. Even when this network is extensive, the large neuron is never completely surrounded. Most often, this cell also borders a fascicle of internal capsule fibers, and the entire cellular island may be aligned either parallel to or perpendicular to the orientation of these fibers. These findings suggest the hypothesis that cellular territories in the caudate-putamen nucleus have a very specific orientation in three dimensional space.
Calculations and measurements of β-ray attenuation for determining density in an inhomogenous medium

Abstract A model for the distribution of tobacco strands in a cigarette is proposed to explain the discrepancy between density as measured by weight and volume and that as measured by β-ray attenuation and to explain the large deviation of the β-ray measurements from the mean path length through the contribute to this uncertainty are slope of the β-ray attenuation curve, the mean path length through the mass element, and the material volume fraction.
The fermi surface and optical properties of copper

Abstract A Fourier expanded model Hamiltonian is applied to copper. The parameters in this phenomenological Hamiltonian are adjusted to fit the de Haas-van Alphen periods, the cyclotron effective masses, and the position of the lowest direct optical interband absorption. The agreement with experiment suggests that the electron-phonon enhancement of the effective mass is small, and that the optical properties are consistent with direct wave-vector conserving transitions between one-electron states.
Cadmium-induced loss of surface polyphosphate in Acinetobacter lwoffi

Cadmium is accumulated in Acinetobacter lwoffi by an active transport process. Growth in synthetic medium is not affected until cadmium concentrations exceed 0.5 μM. Cd uptake is accompanied by release of inorganic phosphate to the medium. 31P-NMR spectra show that the surface polyphosphate pool disappears preferentially in response to Cd.
Changing Support for Civil Rights: House and Senate Voting, 1963-1988

Cohort analysis allows systematic analysis of change in civil rights voting in terms of age, period, and cohort effects. Cohort analysis requires measurements of longitudinal, corss-sectional, and time-lag differences among members of Congress. While offering support for the generational replacement hypothesis, this research suggests that period effects, events in the congressional environment, are important to our understanding of change in civil rights over time.
Rocking response of flexible circular foundations on layered media

Abstract The analysis of the response of a flexible circular foundation on layered media due to an arbitrarily distributed vertical loading is presented. The analysis is based on the ‘ring method’ approach, i.e. discretization of the foundation in a set of concentric rings. The arbitrarily distributed loading is expanded in the circumferential direction in a Fourier series. The influence coefficient matrix of soil for each element of the series is evaluated utilizing the stiffness matrix approach. The stiffness matrix of the foundation is obtained from the finite difference energy method approach. Numerical examples illustrate the influence of several soil-foundation parameters on the rocking response of a foundation. Results are presented in terms of displacement and soil reaction distributions and impedance functions point to significantly different responses of flexible and rigid foundations.
Relative frequency of butchering cutmarks produced by obsidian and flint: an experimental approach

An experimental approach was used to determine how stone tool materials affect the frequency of observed cutmarks. Five whitetail deer were butchered by an expert butcher using flint and obsidian tools and the skeletons were prepared and analyzed. The authors found that the deer butchered with obsidian tools generally displayed fewer incidents of cutmarks than their flint-butchered counterparts. Consideration of this variable may prove to be important to archaeologists attempting to answer questions of specialization or when making comparisons of cutmark data between sites. 2006 Elsevier Ltd. All rights reserved.
Evaluation of coma and brain death

Coma is a nonspecific sign of widespread central nervous system impairment resulting from various metabolic and structural etiologies. The rapid recognition of this neurologic emergency and results from the history, physical examination, and early investigative studies are key to the identification and treatment of its underlying cause. The prognosis for recovery depends greatly on the underlying etiology as well as on its optimal treatment, which seeks to preserve neurologic function and maximize the potential for recovery by reversing the primary cause of brain injury, if known, and preventing secondary brain injury from anoxia, ischemia, hypoglycemia, cerebral edema, seizures, infections, and electrolyte and temperature disturbances. Brain death must be diagnosed with similar care and precision, and families approached compassionately about the diagnosis and their decisions regarding organ donation.
The cause of the voltage “dip” during the high rate discharge of the primary alkaline MnO2/Zn cells

The phenomena of the voltage ‘‘dip’’ during the high rate discharge of the primary alkaline MnO2/Zn cells have been investigated. The ‘‘dip’’ was found anode related. Formation of the type II ZnO film during the high rate discharge was believed to be the cause of the ‘‘dip’’. The majority of the potential ‘‘dip’’ results from the sharp increase of the Ohmic resistance of the zinc gel matrix; the diffusion overpotential across the ZnO film also contributes to the potential ‘‘dip’’. The reactivation is believed to have resulted from the removing of the type II film. 2006 Elsevier B.V. All rights reserved.
Dynamic spreading gain control in multiservice CDMA networks

In this paper, we consider a direct-sequence code division multiple access (DS-CDMA) network consisting of a single radio access point and a collection of wireless terminals. The network offers two classes of service: class-1 (real-time) and class-2 (reliable). We are interested in studying the effect of dynamic spreading gain control (SGC) on the dynamics of multiple access interference (MAI), spectral efficiency, and the quality of service (QoS) experienced by each service class. We first consider a time-slotted system in which class-2 terminals operate in a random access fashion. We show that under optimal (throughput maximizing) dynamic SGC: (1) the optimal retransmission probability is equal to one, and (2) the optimal spreading gain increases linearly, or equivalently, the transmission rate decreases inverse linearly, as the MAI level increases. We then model the system as a continuous-time finite-source queueing system with processor sharing, and obtain an explicit (closed-form) expression for the stationary distribution of the number of active class-1 and class-2 terminals, that is, the MAI level. This distribution is used to derive expressions for various QoS measures and define a capacity or admissible region. The results obtained by simulation and analysis are in extremely close agreement. This work contributes to a better understanding of the relationships between QoS, multiple access interference, and allocation of radio resources in DS-CDMA networks.
Managing product-harm crises:

A new measure of organizational success in dealing with product-harm caused crises is developed. The measure is applied to a hypothetical crisis through the use of scenarios. Important factors during a product-harm crisis are identified and sixteen combinations of those factors' levels are analyzed. Suggestions are then made regarding a troubled organization's appropriate response to the crisis.
A concurrent automatic programming system

Multi-core processors have introduced a greater need for concurrent specifications. Additionally, many specifications require proof of correctness. We present a new automatic programming system designed for the creation, execution, and formal verification of concurrent specifications that is based upon colored Petri nets.
Stable isotope probing with 15N achieved by disentangling the effects of genome G+C content and isotope enrichment on DNA density.

Stable isotope probing (SIP) of nucleic acids is a powerful tool that can identify the functional capabilities of noncultivated microorganisms as they occur in microbial communities. While it has been suggested previously that nucleic acid SIP can be performed with 15N, nearly all applications of this technique to date have used 13C. Successful application of SIP using 15N-DNA (15N-DNA-SIP) has been limited, because the maximum shift in buoyant density that can be achieved in CsCl gradients is approximately 0.016 g ml−1 for 15N-labeled DNA, relative to 0.036 g ml−1 for 13C-labeled DNA. In contrast, variation in genome G+C content between microorganisms can result in DNA samples that vary in buoyant density by as much as 0.05 g ml−1. Thus, natural variation in genome G+C content in complex communities prevents the effective separation of 15N-labeled DNA from unlabeled DNA. We describe a method which disentangles the effects of isotope incorporation and genome G+C content on DNA buoyant density and makes it possible to isolate 15N-labeled DNA from heterogeneous mixtures of DNA. This method relies on recovery of “heavy” DNA from primary CsCl density gradients followed by purification of 15N-labeled DNA from unlabeled high-G+C-content DNA in secondary CsCl density gradients containing bis-benzimide. This technique, by providing a means to enhance separation of isotopically labeled DNA from unlabeled DNA, makes it possible to use 15N-labeled compounds effectively in DNA-SIP experiments and also will be effective for removing unlabeled DNA from isotopically labeled DNA in 13C-DNA-SIP applications.