cssi/SciSciGPT-SciSciNet huggingface dataset:
A Qualitative Study of Undergraduate Racial and Ethnic Minority Experiences and Perspectives on Striving to Enter Careers in the Health Professions.

Background Diversification of the health care workforce by race and ethnicity offers a strategy for addressing health care disparities. This study explored the experiences with pathways programming and mentoring of minority undergraduates aspiring to health professions careers. Methods We interviewed 21 minority undergraduates in 4 focus groups. The interviews explored participants' backgrounds; perceptions of racial climate; exposure to health professions careers, mentors, and pathways programs; barriers to success; and desired support. Results Many participants described diminished confidence and feelings of isolation due to stereotyping and discrimination; some were empowered to pursue health care careers because of adversity. Common themes included desire for mentorship, earlier career exposure, and college readiness support. Discussion Minority students desire health career exposure, mentoring, pre-college advising, and a positive racial climate; unfortunately, these desires often go unmet.
Characterization of an Electronic Corneal Prosthesis System.

Corneal opacity is a leading cause of reversible blindness worldwide. An electronic corneal prosthesis, or intraocular projector, could potentially restore high-quality vision without need for corn...
Development and accuracy assessment of a 12-digit hydrologic unit code based real-time climate database for hydrologic models in the US

Abstract Accurate daily weather data are critical for hydrologic models simulating and predicting hydrologic processes. Many researchers have focused on the impacts of precipitation on hydrologic simulations, but few studies integrated both temperature and precipitation data for historical and forecast periods in hydrologic models and evaluated the weather data accuracy at national scale. This study evaluated four extracting methods (mean (MN), median (MD), centroid (CT), and area-weighted (AW) approaches) for summarizing weather data for sub-watersheds defined in a hydrologic model. Firstly, an optimized extracting method was used to develop a real-time HUC-12 (12-digit Hydrologic Unit Code) level dataset for the Conterminous United States. The hydrologic model with the CT weather data performed the best, followed by MN, AW, and then MD. Secondly, per this method, a real-time dataset including historical and forecast data at HUC-12 level across the conterminous United States was created. Last, continuous daily forecast data at national scale displayed that large forecast overestimations were usually observed in large forecast precipitation events over 20 mm. Simultaneously, there were large underestimations in small forecast precipitation events less than 5 mm. Forecast maximum temperature showed a more substantial bias than that minimum temperature, with the largest underestimation for the lower forecast maximum temperature less than 15 °C. With regard to data stability of the historical observed temperature data, provisional and early temperature data from Parameter-elevation Regressions on Independent Slopes Model (PRISM) in the most recent seven months are as reliable as the stable data that is subject to quality control measures before it replaces the provisional and early data. However, forecast data often included bias in the extreme weather conditions, such as heavy precipitation and scorching temperature. Forecast data, which is updated multiple times each day, was frequently subject to an opposite bias (trending toward less extreme values) in the presence of strong frontal systems presumably due to the exact location and speed of the front being difficult to predict. Fully processed weather data from this work will be published online to facilitate hydrologic modeling efforts in the US and inform users about the uncertainty in the forecast data.
Brokers or Dealers? Trading Intermediation and Market Liquidity

In some markets (e.g. equities), intermediaries execute trades as agents and earn flat commissions while in other markets (e.g. currencies), as principals and earn mark-ups. We argue this choice is driven by the need to incentivize intermediaries to obtain better prices. In principal trading, intermediaries internalizes the execution outcome but need to be compensated for bearing execution risk. In agency trading, investors need to evaluate agents against price benchmarks, and that requires having access to information about trading activities around the same time. Therefore, agency trading is more likely 1) in markets with high transparency and turnover and 2) when intermediary risk aversion is high. Cross-market outcomes are consistent with theory. We further validate prediction 2) using shocks to intermediary capital during financial crisis.
BBR Bufferbloat in DASH Video

BBR is a new congestion control algorithm and is seeing increased adoption especially for video traffic. BBR solves the bufferbloat problem in legacy loss-based congestion control algorithms where application performance drops considerably when router buffers are deep. BBR regulates traffic such that router queues don’t build up to avoid the bufferbloat problem while still maintaining high throughput. However, our analysis shows that video applications experience significantly poor performance when using BBR under deep buffers. In fact, we find that video traffic sees inflated latencies because of long queues at the router, ultimately degrading video performance. To understand this dichotomy, we study the interaction between BBR and DASH video. Our investigation reveals that BBR under deep buffers and high network burstiness severely overestimates available bandwidth and does not converge to steady state, both of which results in BBR sending substantially more data into the network, causing a queue buildup. This elevated packet sending rate under BBR is ultimately caused by the router’s ability to absorb bursts in traffic, which destabilizes BBR’s bandwidth estimation and overrides BBR’s expected logic for exiting the startup phase. We design a new bandwidth estimation algorithm and apply it to BBR (and a still-unreleased, newer version of BBR called BBR2). Our modified BBR and BBR2 both see significantly improved video QoE even under deep buffers.
Noninvasive THz Measurement of Intraocular Pressure

Endothelial damage related to elevated intraocular pressure (IOP) was investigated using a THz corneal scanner. An increase in the IOP in rabbit and porcine eyes corresponded to increased THz reflectivity. Endothelial damage was confirmed independently using SEM.
The Dissertation Clinic: Supporting Doctoral Students’ Research Methods Training in an Online EdD Program

“The professional doctorate in education prepares educators for the application of appropriate and specific practices, the generation of new knowledge, and for the stewardship of the profession” (CPED, 2009). The Johns Hopkins University EdD attracts diverse learners with varying experiences with statistics and research methods. These experiences coupled with becoming doctoral students often contributes to high levels of reported anxiety and low confidence related to these topics. Evidence also suggests that this anxiety may contribute to higher rates of attrition in online doctoral programs. Understanding the importance and value of acknowledging our students’ needs, differences, and worries around methods and statistics and recognizing that intentionally working with students in these areas can mitigate this anxiety, the methods faculty in this EdD program set out to create a forum for students, faculty, and advisors to call on for matters related to methods, statistics, and data analysis. This essay offers a description of the Dissertation Clinic, implementation of the clinic and the services offered, as well as next steps and future considerations.
On a Quantum Version of Pieri’s Formula

We give an algebro-combinatorial proof of a general version of Pieri’s formula following the approach developed by Fomin and Kirillov in the paper “Quadratic algebras, Dunkl elements, and Schubert calculus.” We prove several conjectures posed in their paper. As a consequence, a new proof of classical Pieri’s formula for cohomology of complex flag manifolds, and that of its analogue for quantum cohomology is obtained in this paper.
Psychocorporeal Selfhood, Practical Intelligence, and Adaptive Autonomy

How must selfhood be construed given that people are vulnerable to identity crises? How must agency be construed given that some people skirt potential identity crises? After explaining what an identity crisis is, I examine Charles Taylor’s and David Velleman’s accounts of identity, agency, and identity crises. In the spirit of Merleau-Ponty’s account of habit and J. J. Gibson’s account of the relation between corporeity and affordances, I sketch an account of practical intelligence that includes four psychocorporeal components – psychocorporeal virtue, psychocorporeal cognition, psychocorporeal versatility, and psychocorporeal memory. I conclude by connecting my position to Aristotle’s views about practical understanding and by arguing that both Taylor and Velleman have reason to embrace my position.
Export of fine particulate organic carbon from redwood-dominated catchments

Recently, researchers have recognized the significant role of small mountainous river systems in the transport of carbon from terrestrial environments to the ocean, and the scale of such studies have ranged from channel bed units to continents. In temperate zones, these mountain river systems commonly drain catchments that are largely forested. However, the magnitude of carbon export from rivers draining old-growth redwood forests has not been evaluated to date. Old-growth redwood stands support some of the largest quantities of biomass in the world, up to 350 000 Mg of stem biomass km-2 and soil organic carbon can reach 46 800 Mg km-2. In north coastal California, suspended sediment samples were collected at three gaging stations for two to four years on streams draining old-growth redwood forests. Carbon content, determined through loss-on-ignition tests, was strongly correlated with turbidity, and continuous turbidity records from the gaging stations were used to estimate annual carbon exports of 1 · 6 to 4 · 2 Mg km-2 yr-1. These values, representing 13 to 33% of the suspended sediment load, are some of the highest percentages reported in the global literature. The fraction of organic carbon as part of the suspended sediment load decreased with discharge, but reached an asymptote of 5 to 10% at flows 10 to 20 times the mean annual flows. Although larger rivers in this region exhibit high sediment yields (up to 3600 Mg km-2 yr-1), mainly attributed to high rates of uplift, mass movement, and timber harvest, the small pristine streams in this study have sediment yields of only 8 to 100 Mg km-2 yr-1. Because the current extent of old-growth redwood stands is less than 5% of its pre-European-settlement distribution, the present organic carbon signature in suspended sediment loads in this region is likely different from that in the early 20th century. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Improvement of the theoretical minimum detectable angle of the optical beam deflection method

We study the possibility of improving the theoretical limit to the resolution of the optical beam deflection method (OBDM) by reflecting the beam from a curved surface. We suggest a new detection scheme by measuring the average intensity over a cross section of the beam after it is reflected from a cylindrical mirror. We show that there is a possibility of decreasing the theoretical minimum detectable angle (MDA) as compared to the usual OBDM when the beam grazes the cylindrical mirror.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Rupture and transformation of lipid bilayer membranes at thermal phase transitions

Abstract Nuclear magnetic resonance was used to study dimyristoylphosphatidylcholine vesicles. Loss of vesicle contents and transformation to more extended bilayer structures near the gel to liquid crystalline phase transition is related to potential cell membrane damage on lowering environmental temperatures.
Consistent parameterization and statistical analysis of human head scans

Statistical shape analysis of 3-D scanned human heads provides important information for many applications. Nevertheless, special geometry processing techniques have to be developed for consistently parameterizing scans due to the fact that different scanning projects vary in landmark definition, noise control and other factors. For consistent parameterization, fitting a generic model to each scan has proved to be an effective method. In this paper, improved techniques are presented to solve problems in parameterizing different data sets. Principal Component Analysis (PCA) is thus conducted on the consistently parameterized data sets, and shape variances along principal components are demonstrated. In addition, shape variations analyzed by Independent Component Analysis (ICA) are also presented.
Free-atom formation processes in premixed fuel-rich and stoichiometric oxygen-acetylene flames employed in atomic emission and absorption spectroscopy

Abstract Detailed observations on the atomic and molecular absorption and emission spectra of the various zones of premixed oxyacetylene flames are presented. Spatial flame profile data for both the natural flame species and those formed when solutions of metallic salts are nebulized into the flame are interpreted in terms of: (a) the relative concentrations of reactive intermediate and stable species in the various zones; (b) the mechanism of free-atom formation from aerosol droplets; and (c) free-atom depopulation processes. The results of this study clearly show that the striking enhancement in atomic spectra observed in either absorption or emission for many elements in the fuel-rich oxyacetylene flame originate in the favorable chemical environment provided by the interconal zone for the formation and existence of free-atoms.
Global Optimization of Combined Region Aggregation and Leveling Model

The advent and widespread use of innovative spatial analysis technologies, such as geographic information systems (GIS), computer aided design (CAD) systems, and global positioning systems (GPS), have prompted great interest in spatial optimization. The tasks of selecting an optimal subregion from a larger region—region aggregation—and determining an optimal strategy for cutting and filling that subregion to a uniform elevation—land leveling—are examples of spatial analyses that can benefit from these powerful computer technologies. The combined region aggregation and leveling problem is a complex spatial problem that often involves the comprehensive consideration of multiple, incommensurate, and often conflicting objectives, while at the same time satisfying a set of prespecified physical and logical constraints. Traditionally, these two problems are solved separately, often precluding the identification of global optima. Through this research, a multiobjective integer programming model that considers these problems simultaneously is formulated, a computational algorithm for solving the model is presented, and numerical results that demonstrate the efficiency and effectiveness of this procedure are discussed. Computational experiments report polynomial complexity of the heuristic procedure against exponential worst-case complexity of traditional enumerative methods.
Fertility-mycorrhizal-isolate interactions in production of containerized pin oak seedlings

Abstract Slow-release fertilizer rates (0, 1.1 and 4.5 kg/m 3 of 14 N-6 P-11.6 K Osmocote) and isolates of the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch affected growth and mycorrhizal development on pin oak ( Quercus palustris Meunchh.) seedlings. Mycorrhizae developed on all inoculated seedlings after 8 weeks regardless of fertility regime. Through the first 14 weeks, the best mycorrhizal development occurred on all inoculated seedlings fertilized at the lower fertilizer rate. The higher fertilizer rate delayed mycorrhizal development. However, after 18 weeks there were no significant differences in mycorrhizae on inoculated seedlings receiving fertilizer. Inoculated, non-fertilized seedlings had significantly less mycorrhizae than fertilized seedlings throughout the experiment. Only one isolate increased seedling growth, and only at the higher fertilizer rate. No differences in plant height were found among non-inoculated control and inoculated seedlings at the low fertilizer rate.
Analysis of Fourier-domain task-based detectability index in tomosynthesis and cone-beam CT in relation to human observer performance

Purpose: Design and optimization of medical imaging systems benefit from accurate theoretical modeling that identifies the physical factors governing image quality, particularly in the early stages of system development. This work extends Fourier metrics of imaging performance and detectability index (d′) to tomosynthesis and cone-beam CT (CBCT) and investigates the extent to which d′ is a valid descriptor of task-based imaging performance as assessed by human observers. Methods: The detectability index for tasks presented in 2D slices (dslice′) was derived from 3D cascaded systems analysis of tomosynthesis and CBCT. Anatomical background noise measured in a physical phantom presenting power-law spectral density was incorporated in the “generalized” noise-equivalent quanta. Theoretical calculations of dslice′ were performed as a function of total angular extent (θtot) of source-detector orbit ranging 10°–360° under two acquisition schemes: (i) Constant angular separation between projections (constant-Δθ), giving variable number of projections (Nproj) and dose vs θtot and (ii) constant number of projections (constant-Nproj), giving constant dose (but variable angular sampling) with θtot. Five simple observer models were investigated: Prewhitening (PW), prewhitening with eye filter and internal noise (PWEi), nonprewhitening (NPW), nonprewhitening with eye filter (NPWE), and nonprewhitening with eye filter and internal noise (NPWEi). Human observer performance was measured in 9AFC tests for five simple imaging tasks presented within uniform and power-law clutter backgrounds. Measurements (from 9AFC tests) and theoretical calculations (from cascaded systems analysis of dslice′) were compared in terms of area under the ROC curve (Az) Results: Reasonable correspondence between theoretical calculations and human observer performance was achieved for all imaging tasks over the broad range of experimental conditions and acquisition schemes. The PW and PWEi observer models tended to overestimate detectability, while the various NPW models predicted observer performance fairly well, with NPWEi giving the best overall agreement. Detectability was shown to increase with θtot due to the reduction of out-of-plane clutter, reaching a plateau after a particular θtot that depended on the imaging task. Depending on the acquisition scheme, however (i.e., constant-Nproj or Δθ), detectability was seen in some cases to decline at higher θtot due to tradeoffs among quantum noise, background clutter, and view sampling. Conclusions: Generalized detectability index derived from a 3D cascaded systems model shows reasonable correspondence with human observer performance over a fairly broad range of imaging tasks and conditions, although discrepancies were observed in cases relating to orbits intermediate to 180° and 360°. The basic correspondence of theoretical and measured performance supports the application of such a theoretical framework for system design and optimization of tomosynthesis and CBCT.
The D1 C-terminal processing protease of photosystem II from Scenedesmus obliquus. Protein purification and gene characterization in wild type and processing mutants.

Polypeptide D1 of the photosystem II reaction center of oxygenic photosynthesis is expressed in precursor form (pre-D1), and it must be proteolytically processed at its C terminus to enable assembly of the manganese cluster responsible for photosynthetic water oxidation. A rapid and highly sensitive enzyme-linked immunosorbent assay-based microtiter plate method is described for assaying this D1 C-terminal processing protease. A protocol is described for the isolation and purification to homogeneity of the enzyme from the green alga, Scenedesmus obliquus. Amino acid sequence information on the purified protease was used to clone the corresponding gene, the translated sequence of which is presented. A comparison of the gene product with homologous proteases points to a region of conserved residues that likely corresponds to the active site of a new class of serine protease. The LF-1 mutant strain ofScenedesmus (isolated by Dr. Norman Bishop) is incapable of processing pre-D1. We show here that the C-terminal processing protease gene in this strain contains a single base deletion that causes a frame shift and a premature stop of translation within the likely active site of the enzyme. A suppressor strain, LF-1-RVT-1, which is photoautotrophic and capable of processing pre-D1 has a nearby single base insertion that restores the expression of active enzyme. These observations provide the first definitive proof that the enzyme isolated is responsible for in vivo proteolytic processing of pre-D1 and that no other protease can compensate for its loss.
Depositional and Diagenetic Model for Brine Related Stratiform Mineralization: Atlantis II Deep, Red Sea: ABSTRACT

Genetic models of many massive sulfide deposits postulate deposition of metalliferous sediment by venting of high-salinity hydrothermal fluids onto the sea floor. The Atlantis II deep, Red Sea, is a currently active modern example of such a process. Areal extent of the brine pool in the Atlantis II deep exerts primary control on the distribution of metalliferous sediment. The presence of a density-stratified brine pool allows dispersion of undiluted metal-rich brine to all parts of the deep. Currently, brine vents in the Southwest basin, advects vertically to the density interface between the brine pool and overlying sea water, and then flows laterally along the interface. The lower brine mass is isolated from oxygenated sea water, allowing base metal sulfides to precipit te in areas distal from the site of venting. The metalliferous sediments are extremely fine grained with interstitial water contents in the uppermost sediments of greater than 98% by weight. Sedimentation rates inside the brine pool are in excess of 100 cm/1,000 years. High salinity, high temperature, and high trace-metal content of the brine produce a toxic environment which ensures that the finely laminated sediments are not disturbed by bioturbation. However, metalliferous sediment deposited in the area of active brine venting is highly disturbed, with common features of soft sediment deformation. Heterolithic and homolithic breccias occur, some of which are metalliferous turbidites dislodged, by tectonic activity, from steep graben walls flanking the deep. Influx of new brine causes urther disruption and deposition of epigenetic minerals in veins which cut unlithified metalliferous sediment. End_of_Article - Last_Page 646------------
Choice between stimuli previously presented separately

Abstract Three experiments examined the choice behavior of pigeons in a chamber with two adjacent keys that could each be lit with either a red or a green dot. In each experiment subjects first received several sessions of separate-stimulus training with only one color present on each trial, then a choice test with both colors present on each trial. Trials lasted a fixed period of time regardless of the number of pecks that occurred, with earned reinforcements presented at the end of the trial; no reinforcement was available during choice tests. When separate-stimulus training was arranged so that more reinforcements occurred per unit time with S 1 present than with S 2 present, either because responding was reinforced on a higher proportion of S 1 trials or because S 1 trials were shorter, S 1 was pecked more often on the subsequent choice test. When reinforcements per unit time with the stimulus present were held constant, a number of other variables had little or no effect on subsequent choice, including total number of trials presented, proportion of trials followed by reinforcement, trial length, and total number of reinforcements per session with each stimulus.
Long-term efficacy of diltiazem in chronic stable angina associated with atherosclerosis: effect on treadmill exercise.

Short-term efficacy of diltiazem in prolonging exercise end points in patients with chronic stable atherosclerosis-associated angina has been demonstrated. The safety and efficacy of diltiazem were examined in a placebo-controlled exercise study over 4 months (eight patients) and subsequently at 12 to 16 months (six patients). Three end points were evaluated: (1) time to onset of angina or fatigue if angina were eliminated; (2) time to 1 mm S-T segment depression or termination of exercise if S-T depression were eliminated; and (3) time to termination of exercise (2 + angina or fatigue). All end points were significantly prolonged over the medium-term 4 month study and decreased again significantly with return to placebo. Maximal effect occurred at 3 months with the first end point increasing from a mean ± standard error of the mean of 7.2 ± 1.2 to 10.2 ± 0.9 minutes (p
The direct release of nitric oxide by gypenosides derived from the herb Gynostemma pentaphyllum.

Herbal medicines are increasingly being utilized to treat a wide variety of disease processes. Gypenosides are triterpenoid saponins contained in an extract from Gynostemma pentaphyllum and are reported to be effective in the treatment of cardiovascular diseases; however, the mechanism underlying the therapeutic effect is not known. We tested the hypothesis that gypenosides extracted from G. pentaphyllum elicit vasorelaxation through the direct release of endothelium-derived nitric oxide. Nitric oxide production in bovine aortic endothelial cells grown under standard tissue culture conditions was quantitated using a chemiluminescence method. Arterial vasomotion was assayed using isolated porcine coronary artery rings under standard isometric recording conditions. The extract of G. pentaphyllum at 0.1-100 microg/ml elicited concentration-dependent vasorelaxation of porcine coronary rings that was antagonized by the nitric oxide synthase inhibitor N(G)-nitro-l-arginine methyl ester. Indomethacin had no significant effect on G. pentaphyllum-induced relaxation. The G. pentaphyllum extract elicited a concentration-dependent increase in nitric oxide production from cultured bovine aortic endothelial cells. At the concentrations utilized, there was no morphological evidence for cellular toxicity. These results demonstrate that extracts of G. pentaphyllum directly stimulate nitric oxide release, but not prostanoid production. Nitric oxide production in response to gypenosides may be one mechanism whereby this herbal medicine elicits its therapeutic effects.
Smart meters and public acceptance: comparative analysis and governance implications

Although smart meters for electricity have received widespread acclaim as a means to achieve more resilient and sustainable electricity consumption, public opposition has emerged in several countries. In this article, I examine the reasons for public opposition in North America and the role of concern with health risks. The article provides an analysis of reasons given for opposing smart meters by 75 US and Canadian organisations listed in the 2013 EMF (electromagnetic field) Safety Network, a review of all news reports (499) in the Lexis-Nexis database relating to smart meters in seven US states and one Canadian province from 2010 to 2013 and case studies of policy responses in the same seven states and province. Thirty-one of the organisations in the EMF network focused mainly on health concerns about EMFs, and 44 organisations identified broader concerns as well as health risks. The more politically conservative groups focused on issues relating to privacy and government intrusion. Newspaper reports al...
A two-dimensional retrodirective array using slot ring FET mixers

A printed 4-by-4 retrodirective antenna array has been developed, which employs the heterodyne phasing technique at 6 GHz. Each array element comprises a balanced FET resistive mixer, integrated in a ring slot which serves as both an antenna and hybrid. Driven by a reference signal at twice the incident frequency, the mixers receive and reradiate incident signals while imparting a conjugate phase shift onto them. The result is retrodirective radiation that is not critically dependent on either the array geometry or the planarity of the wavefront. This makes conformal retrodirective arrays possible. The backscatter pattern of the array exhibits a wide-angle response (>100 degree scan range) in both planes.
Fiber-reinforced polymer composites for civil infrastructure in the USA

The use of fiber-reinforced composites in civil infrastructure has increased dramatically over the past few years. In areas such as seismic retrofitting of columns and flexural strengthening of deteriorated or deficient reinforced concrete beams, this technology is being rapidly accepted as a competitive alternative to conventional methods. Research and field demonstrations in the area of bridge decks and new structural systems have also increased. A number of challenges still exist, however, before fiber-reinforced composites are widely accepted by the civil engineering community, including the development of codes and guidelines, the resolution of durability issues, and the education of engineers.
Contributions of Motivational Orientation to Appraisal and Emotion

This study examined the role of affiliative orientation as a dispositional antecedent of appraisals of motivational relevance and related emotions. Individuals high and low on affiliative orientation attempted to complete a teaching task that proved to be interpersonally challenging, and their appraisals and emotions were assessed both while anticipating the task and after its completion. Results indicated that before the task occurred, high levels of affiliative orientation were related to emphasizing the affiliative relevance of the situation, appraising the interpersonal aspects of the situation as being especially important, and experiencing higher levels of interest and lower levels of boredom. Path analyses indicated that the interrelations among these variables were consistent with an a priori causal model of appraisal-emotion relations. Posttask, very few effects of affiliative orientation on appraisal, emotion, or the participants' behaviors during the task were observed.
Infrared Spectra and Density Functional Calculations of Small Vanadium and Titanium Carbonyl Molecules and Anions in Solid Neon

Laser-ablated vanadium and titanium atoms were reacted with CO molecules during condensation in excess neon. The V(CO)x and Ti(CO)x (x = 1−6) molecules are formed during deposition or on annealing and photolysis. The V(CO)x-, Ti(CO)x- (x = 1−6) anions and TiCO+ cation are also produced and identified on the basis of isotopic substitution and density functional calculations. Selective photolysis and CCl4 doping experiments strongly support the identification of the anions and cation.
Beyond Hollywood: Enhancing Heritage with the ‘Orphan’ Film

Global discussions relating to heritage preservation, with their traditional focus upon architecture, archaeological sites, and landscape, often overlook and, at times, even devalue the role of the moving image. The last century witnessed the emergence and development of moving image preservation practice, which largely remains a separate vocation with a unique agenda and approach. With a case study of historical conservation and presentation in San Antonio, Texas, this paper argues for greater dialogue and collaboration between moving image archivists and traditional heritage preservation practitioners. Creative use of archival media offers unparalleled opportunities to illustrate and explore the development and historical trajectory of heritage sites, the visitors to them and, most importantly, the local communities that participate in and facilitate the evolution of this heritage.
Achalasia of the esophagus

Summary Achalasia is a neuromuscular disorder of the esophagus associated with the degeneration or absence of the myenteric nerve plexuses. Peristalsis is uncoordinated or absent in the body of the esophagus; this, coupled with failure of the gastroesophageal sphincter to relax, results in dysphagia. The hypersensitive muscular response to methacholine occurs classically in achalasia and allows an early diagnosis to be made, which is when treatment is more effective. The two most commonly used methods of management are forceful bougienage and extramucous esophagocardiomyotomy. Both procedures are most effective in early stages of achalasia. Each procedure has its advocates and each has its rightful role. The patient with a redundant sigmoid-shaped esophagus is best considered for myotomy; dilatation in these circumstances may be hazardous. Patients with associated conditions such as hiatal hernia, epiphrenic diverticula, suspected gastroesophageal malignancy, peptic ulcer disease, and recurrent achalasia after myotomy are best treated surgically. The direct surgical approach has merit not only in treatment of the patients with achalasia intractable to conservative measures but also as an alternative to repeated bougienage. Good to excellent results were obtained in 78 per cent of the patients who underwent cardiomyotomy; various types of bougienage yielded good to excellent results in 45 per cent. When extensive dilatation, redundancy, and kinking of the esophagus have developed, careful, unhurried, and deliberate cardiomyotomy accomplished under direct vision and with absolute control of the length, breadth, and extent of the myotomy is less hazardous. In this series, there was no mortality and the incidence of postoperative esophagitis was low. The number of esophageal perforations (three patients; 5.5 per cent) from forceful bougienage, the total lack of mortality, and the gratifying results have led us in recent years to use cardiomyotomy frequently as the primary treatment for achalasia.
A quantitative melatonin bioassay

Abstract A sensitive, specific bioassay, based on the dermal melanophore response of larval amphibians, for the quantitative estimate of melatonin is presented. The culturing methods employed to produce the Rana pipiens larvae used in this assay are also outlined.
MILLS' URBAN SYSTEM MODELS -- PERSPECTIVE AND TEMPLATE FOR LUTE (LAND USE/TRANSPORT/ENVIRONMENT) APPLICATIONS.

Abstract Linear programming models of spatial economy (Mills, 1972, 1974a, 1974b, 1975) have prompted the development of several diverse extensions. The purpose of this paper is to review and assess the impact of Mills' model on the development of its derivatives, and to evaluate the role of these models in the development of LUTE (Land Use / Transport / Environment) formulations. These models are assessed and reviewed by dividing them into four categories: (1) static urban linear programming models; (2) static nonlinear programming models; (3) static regional scale models; and (4) dynamic models, including intertemporal and sequential programming models. An extended Mills model is proposed that combines intertemporal production and transportation with pollution control—a prototype LUTE application.
Inner-City Older Blacks Have High Levels of Functional Disability

OBJECTIVES: To describe the frequency and severity of functional problems in two groups of noninstitutionalized inner-city blacks aged 70 years and older contrasted with results from appropriate groups of white and black older adults and with the goals of the Healthy People 2000 program. DESIGN: Cross-sectional descriptive study. SETTING: Community-based samples. PARTICIPANTS: A population-based sample of 416 older adults living in a 3.5-square mile catchment area in north St. Louis (NSL), Missouri, and a sample of 197 older residents living in public housing in East St. Louis (ESL), Illinois. MEASUREMENTS: Health status, preventive health activities, health services utilization, and risks for progressive frailty were assessed by self report and observation using well validated, standardized instruments. Whenever possible, comparison data were derived from national datasets, original samples used to validate the measures, and other useful comparison groups. RESULTS: The NSL sample had somewhat better health status and risk for progressive disability than the ESL sample. However, compared with national or regional reference groups using age-gender adjustments, both study groups demonstrated increased levels of dependence in intermediate activities of daily living, restricted activity days, inability to walk one-half mile without assistance, reported poor vision, living alone, and limited income compared with both older whites and blacks, and increased levels of worsening health, inability to perform heavy work around the house, never walking a mile or more, and currently unmarried versus whites with variable decrements versus blacks. Contrasted with other comparison groups, the two samples had increased body fat; consistent decrements in gait speed, timed chair stands, timed one-leg balance, and frequency of preventive exercise; and lower levels of dental care; results relative to physician visits and hospital days were mixed. They also had high levels of measured visual and hearing impairments, unmet needs for home delivered meals, and problems with false teeth. Deficiencies compared with the goals of Healthy People 2000 were large. CONCLUSIONS: The special attributes of inner-city blacks, including poverty and access to and acceptance of remedial programs, will have to be considered if the goals of Healthy People 2000 are to be met in this important and growing segment of older Americans.
Particular solution of infinite-dimensional linear systems with applications to trajectory planning of boundary control systems

This paper considers a general class of infinite-dimensional linear control systems described by either a state-space (SCS) or boundary control (BCS) system formulation. A key objective of the paper is to accomplish trajectory planning of a BCS through a ‘stable’ dynamic inversion without resorting to discretization. To this end, the paper first formulates the particular solution of an infinite-dimensional SCS within a Sobolev space together with a set of necessary and sufficient conditions for its existence and an explicit formula for computing it. The resulting solution, which may be noncausal, is further utilized to explicitly compute the bounded control input needed for output tracking of a BCS without requiring its inverse to be minimum phase or even to possess a \(C_{0}\)-semigroup. The key results of the paper are illustrated on a flexible beam and a one-dimensional heat conduction system.
Electronic and vibronic contributions to two-photon absorption in donor-acceptor-donor squaraine chromophores.

Many squaraines have been observed to exhibit two-photon absorption at transition energies close to those of the lowest energy one-photon electronic transitions. Here, the electronic and vibronic contributions to these low-energy two-photon absorptions are elucidated by performing correlated quantum-chemical calculations on model chromophores that differ in their terminal donor groups (diarylaminothienyl, indolenylidenemethyl, dimethylaminopolyenyl, or 4-(dimethylamino)phenylpolyenyl). For squaraines with diarylaminothienyl and dimethylaminopolyenyl donors and for the longer examples of 4-(dimethylamino)phenylpolyenyl donors, the calculated energies of the lowest two-photon active states approach those of the lowest energy one-photon active (1Bu) states. This is consistent with the existence of purely electronic channels for low-energy two-photon absorption (TPA) in these types of chromophores. On the other hand, for all squaraines containing indolinylidenemethyl donors, the calculations indicate that there are no low-lying electronic states of appropriate symmetry for TPA. Actually, we find that the lowest energy TPA transitions can be explained through coupling of the one-photon absorption (OPA) active 1Bu state with bu vibrational modes. Through implementation of Herzberg–Teller theory, we are able to identify the vibrational modes responsible for the low-energy TPA peak and to reproduce, at least qualitatively, the experimental TPA spectra of several squaraines of this type.
Aspect angle estimation of targets in forward-looking infrared images using the model-based vision approach

We develop a model-based vision algorithm to estimate the aspect angle of a target in a forward-looking infrared (FLIR) image. In the preprocessing stage of the algorithm, a set of 3-D voxel-based models is created using a CAD/CAM package. These models are rotated about the vertical axis through a series of predetermined angles and then projected onto the horizontal plane. This gives us a database library of 2-D images. We select as signature from a given FLIR image and attempt to match it with the various images in the given database library of images using the normalized cross-correlation method. The angle of rotation corresponding to the image in the database library giving the best possible match is estimated to be the aspect angle of the signature (target). We use an algebraic approach to represent images and the process involves certain algebraic operations on the polynomials. An advantage of the algebraic approach is that a high speedup in the run time is possible if the fast Fourier transform is used to compute the polynominal multiplications involved in the processing.
Methodology for Determining Laboratory and In Situ Hydraulic Conductivity of Asphalt Permeable Friction Course

The permeable friction course (PFC) is a layer of porous asphalt pavement overlain on conventional impervious hot-mix asphalt or portland cement concrete. The drainage properties of PFC are typically considered to be governed primarily by two hydraulic properties: hydraulic conductivity and porosity. Both of these hydraulic properties change over the life cycle of the PFC layer due to clogging of the pore space by sediment. Therefore, determination of the hydraulic conductivity and porosity of PFC can be problematic. Laboratory and particularly field tests are necessary for accurately determining the hydraulic conductivity of the PFC layer. Taking multiple measurements over the life of the pavement shows how these hydraulic characteristics change with time and the varying roadway conditions at which they are evaluated. Constant head laboratory testing has shown that PFC experiences a nonlinear flow relationship as described by the Forchheimer equation. In addition to the laboratory analysis of the hydraulic characteristics, a falling head field test is recommended to determine the in situ hydraulic conductivity. This incorporates the modeling techniques used in the laboratory testing and applies them to the falling head conditions used in the field. The result is a nondestructive test procedure for determining the in situ hydraulic conductivity which is necessary for estimating the extent to which the benefits associated with the drainage characteristics of the PFC layer will persist.
Synthesis of cholesterol and total lipid by male and female rats fed beef tallow or corn oil

Male and female weanling rats were fed diets containing 2 or 42% of calories as corn oil or 40% as beef tallow plus 2% as corn oil until they were 12 or 18 weeks of age. Incorporation of C(14)-acetate into lipids of serum and liver and concentration of lipids in serum, liver, and carcass at the end of these periods were determined.Net synthesis of noncholesterol lipid was repressed by changing the diet from 2% to 42% of calories from either dietary fat in both sexes and at both ages. Cholesterol net synthesis was enhanced 29-fold in males and 22-fold in females fed 42% corn oil compared to 2% corn oil to the age of 12 weeks. It was enhanced only 2.6-fold for males and 3.4-fold for females by 40% beef tallow plus 2% corn oil. At 18 weeks of age cholesterol synthesis in males fed 42% corn oil was 7.3 and in females 9.1 times the value for those fed 2% corn oil. At this age the values for rats fed 40% beef tallow plus 2% corn oil were 1.2 and 3.7 times those for 2% corn oil fed rats of the respective sexes.
Ion Mobility Spectrometry/Mass Spectrometry Snapshots for Assessing the Molecular Compositions of Complex Polymeric Systems

The synthesis of increasingly complex polymers has created daunting, sometimes insurmountable problems for their chemical analysis. The importance is magnified by outsourcing of production and their use in consumer products, including medical devices and food storage, and therefore requires a new generation of technology for quality assurance. Here, we report capturing subtle differences at the molecular level in complex polymer mixtures nearly instantaneously using a prototype multidimensional ion mobility spectrometry/mass spectrometry spectrometry instrument. Bulk activation/fragmentation strategies reported here provide signatures of structural characteristics that permit effortless recognition of minor differences in blends and copolymers, even as structural isomers and from a quantitative perspective. The data displayed as a pictorial snapshot provide a visual pattern that is sufficiently distinctive that computer-aided pattern recognition can be used to address process control and regulatory issues.
Characterization of thermal transport in low-dimensional boron nitride nanostructures

Recent advances in the synthesis of hexagonal boron nitride (BN) based nanostructures, similar to graphene, graphene nanoribbons, and nanotubes, have attracted significant interest into characterization of these materials. While electronic and optical properties of BN-based materials have been widely studied, the thermal transport has not been thoroughly investigated. In this paper, the thermal transport properties of these BN nanostructures are systematically studied using equilibrium molecular dynamics with a Tersoff-type empirical interatomic potential which is re-parametrized to represent experimental structure and phonon dispersion of two-dimensional hexagonal BN. Our simulations show that BN nanostructures have considerably high thermal conductivities but are still quite lower than carbon-based counterparts. Qualitatively, however, the thermal conductivity of carbon and BN nanoribbons display similar behavior with respect to the variation of width and edge structure (zigzag and armchair). Additionally, thermal conductivities of $(10,10)$ and $(10,0)$ nanotubes, both carbon and BN, are found to have very weak dependence on their chirality.