cssi/SciSciGPT-SciSciNet huggingface dataset:
A cost‐benefit analysis of military aircraft replacement policies

This paper describes a method of solving aircraft service life problems. The particular application concerns aircraft in the Naval Advanced Jet Training Command. The method of solution is comparative present value analysis of alternative replacement policies. The likely risks of estimation errors are reflected in the comparisons of present values. Differences are noted in the benefits associated with each policy, but external to Naval Aviation. Since the values of these benefits can be determined only at a higher level of decision-making, the result of the study is not a conclusive selection among policies, but a schedule of present values on the basis of which, together with values of the external benefits, a decision can be reached. This paper discusses replacement policies for aircraft used in the Naval Advanced Jet Pilot Training mission. Taking engineering technology and the training syllabus as given, four feasible plans for introducing replacement aircraft into service are evaluated in terms of the present values of differential costs associated with the plans and in terms of the likely errors in cost estimates used in calculation of the present values. The trade-off between present value of costs and planning flexibility is emphasized in choosing a recommended time pattern of aircraft replacement. The specific aircraft mixes considered are the TF–9J/TAF–9J and the TA–4F/A–4B. The first is the currently employed mix; the second is the proposed replacement. The problem is to select an optimal time-pattern of replacement of F–9's by A–4's, given technological differences favoring the A–4 and increasing costs of maintaining squadrons of F–9's. Replacements by aircraft types other than the A–4 are considered impractical. Four feasible plans for introducing A–4's through a 5-year period are evaluated in terms of current best estimates of the related costs of the plans and in terms of the flexibility of modifying each plan given future better information concerning the relevant costs. The method of analysis is comparative present value of expected costs.
The Edge of Chaos: School Administrators and Accountability.

Much has been written about student accountability, teacher accountability, and school accountability. More limited research is available on administrator accountability. Recently there have been substantial initiatives undertaken world‐wide to increase educational accountability. With increasing demands and changing expectations in the role of school administration, researchers, practitioners and policy makers and departments of education have become socially preoccupied with educational accountability. The purpose of this article is to provide a comprehensive literature review on accountability of school administrators over the last two decades to demonstrate how aspiring, new and practicing school administrators understand and meet the demands of accountability in a time of tumultuous change when the stakes are high.
Tuesday keynote: Video communication for the 21st century

Video has become a pervasive communication medium with mainstream platforms such as YouTube, Skype, FaceTime, and Hangouts having enormous penetration in society, and new video start-ups announced almost daily. Despite the rise of video, we argue that we have only scratched the surface of the potential that video has to enrich our everyday lives. Too often we only think of video as a technology to share a funny cat video or call a distant friend or relative. Similar to how text messaging evolved and changed the way people communicate, video provides new opportunities to enrich and augment existing forms of communication. The neXus Group at Microsoft Research is exploring next generation video to enable anytime, anywhere video communication that moves beyond traditional “talking heads” to support rich shared experiences. This talk will showcase some of the many ways video is changing how we interact with others and justify why we should embrace the video generation. Video is already being used to enhance many activities in our daily lives, however, current tools are not well designed to support people doing things together. To better understand the challenges and opportunities in this space, we have explored ways video can enhance daily activities such as homework, shopping, watching TV, and going to the park, as well as special occasions like birthday parties or concerts and festivals. Results from this work reveal opportunities to enhance video communication systems and move beyond talking heads to enable remote people to truly “be together” and “do things together”.
Total synthesis of acetate from CO2. 3. Inhibition by alkylhalides of the synthesis from CO2, methyltetrahydrofolate, and methyl-B12 by Clostridium thermoaceticum.

Abstract The synthesis of acetate from CO2 by cells of Clostridium thermoaceticum fermenting glucose was inhibited by propyl iodide, chloroform, and carbon tetrachloride. Cell-free extracts when fermenting pyruvate synthesized acetate from CO2, but to a very small extent. However, they converted the methyl groups of N-5-methyltetrahydrofolate and Co-methylcobalamin efficiently to the methyl group of acetate in the presence of pyruvate and ferrous ions. The formation of acetate from either of these methyl donors was inhibited by propyl iodide and carbon tetrachloride. Extracts inhibited by propyl iodide were reactivated by photolysis. With radioactive propyl iodide it was shown that propylated corrinoids were present in the inhibited extract and in whole cells. It is proposed that the inhibitory action of the alkyl halides is by alkylation of a corrinoid enzyme. The transmethylation is thus prevented from methyltetrahydrofolate to the corrinoid enzyme as well as the subsequent carboxylation to yield acetate.
A highly active phosphoglucomutase from Clostridium thermocellum: cloning, purification, characterization and enhanced thermostability.

Aims: Discovery and utilization of highly active and thermostable phosphoglucomutase (PGM) would be vital for biocatalysis mediated by multiple enzymes, for example, high-yield production of enzymatic hydrogen. Methods and Results: The thermophilic cellulolytic bacterium Clostridium thermocellum was hypothesized to have a very active PGM because of its key role in microbial cellulose utilization. The Cl. thermocellum ORF Cthe1265 encoding a putative PGM was cloned and expressed in Escherichia coli. The purified enzyme appeared to be a monomer with an estimated molecular weight of 64·9 kDa. This enzyme was found to be a dual-specificity enzyme – PGM/phosphomannomutase (PMM). Mg2+ and Mn2+ were activators. Ser144 was identified as an essential catalytic residue through site-directed mutagenesis. The kcat and Km of PGM were 190 s−1 and 0·41 mmol l−1 on glucose-1-phosphate and 59 s−1 and 0·44 mmol l−1 on mannose-1-phosphate, respectively, at 60°C. Thermostability of PGM at a low concentration (2 nmol l−1, 100 U l−1) was enhanced by 12-fold (i.e. t1/2 = 72 h) at 60°C with addition of bovine serum albumin, Triton X-100, Mg2+and Mn2+. Conclusions: The ORF Cthe1265 was confirmed to encode a PGM with PMM activity. This enzyme was the most active PGM reported. Significance and Impact of the Study: This highly active PGM with enhanced thermostability would be an important building block for in vitro synthetic biology projects (complicated biotransformation mediated by multiple enzymes in one pot).
Photophysiology in two southern ocean phytoplankton taxa: Photosynthesis of Phaeocystis Antarctica (prymnesiophyceae) and Fragilariopsis Cylindrus (bacillariophyceae) under simulated mixed-layer irradiance

In the Ross Sea, the prymnesiophyte Phaeocystis antarctica G. Karst. dominates deeply mixed water columns, while diatoms dominate shallower mixed layers. Understanding what controls the dynamics of these two phytoplankton taxa is essential because they dominate virtually all coastal polar waters, have different nutrient utilization characteristics, and support dissimilar food webs. We cultured two strains of P. antarctica and one strain of the diatom Fragilariopsis cylindrus (Grunow) Willi Krieg under three dynamic irradiance regimes that simulated different mixed-layer depths and measured their photosynthetic characteristics, cellular pigment concentrations, and cellular carbon and nitrogen content. In both species, chl a–normalized maximum carbon uptake rate (Pm* ) and specific growth rate were highest in the deeply mixed treatment that had a dark period. In all irradiance treatments, both (Pm* ) and photosynthetic efficiency (α*) were greater for the two P. antarctica strains than for the F. cylindrus strain. In contrast, P. antarctica strains were more susceptible to photoinhibition (β*) than the F. cylindrus strain. When photosynthetic rates of each phytoplankton taxon were normalized by cellular particulate organic carbon (POC), the difference in the maximal photosynthetic rate () was generally reduced. In the dynamic irradiance treatment that simulated the shallowest mixed-layer irradiance, all three phytoplankton had similar ; however, the diatom had a 2-fold higher POC-normalized photosynthetic efficiency (αC). Finally, we performed calculations using the measured POC-normalized photosynthetic parameters to show that αC and can play a greater role than βC in determining the competitive outcome between P. antarctica and F. cylindrus in both shallow and deep mixed-layer environments of the Ross Sea.
When groups go wrong

Janice H. Schopler, MSW, is Assistant Professor, and Mae da J. Galinsky, Ph.D., is Professor, School of Social Work, University of North Carolina at Chapel Hill. This research was sup ported by a grant from the University Research Council of the University of North Carolina at Chapel Hill. The authors wish to thank Pam Myers Kiser and Ellen J. Safier for their help in conducting the research reported in this article. Social work educators and prac titioners spend a large portion of their time in treatment, community, educa tional, staff, and growth groups as leaders, members, and observers. De spite social workers' involvement, some groups have damaging effects on their members. Individuals may become de pressed, disillusioned, or disheartened by their group experiences. For some, these effects may be momentary; for others, lasting. The articles and research that were stimulated by concerns about the en counter movement of the 1960s estab lished that negative outcomes can re sult for members engaged in all types of groups and identified some of the fac tors associated with negative group ex periences.1 The authors' review of the group literature indicated that negative outcomes originate from both personal and interpersonal sources that include individual characteristics of members and leaders, properties of the group, and aspects of the group's environ ment.2 Because factors related to the properties of the group and its lead ership are most amenable to the social worker's control, the worker should know what particular group dimensions are most likely to be associated with harmful group experiences in the mind of leaders, members, and observers. Practitioners who are aware of these dimensions might be more effective in preventing and dealing with any damaging consequences. Furthermore, for social workers involved in groups to become more sensitive to the develop ment of potentially harmful group properties, they need to know whether leaders, members, and observers are likely to agree or differ with their per ceptions of the source of negative out
Invariant parameters of measurement scales

Parameter functions are functions of scales. We define the absolute invariance, reference invariance and comparison invariance of parameter functions, and derive some properties of and methods of constructing invariant parameter functions. The results are discussed in relation to the invariance of statistical parameters.
Real Time Tracking Measurements of a Time-Varying Comlex Impedance at K-Band Using Three Fixed Probes

Three-probe microwave automatic impedance measuring system has been designed and used in many places. The principle of this system is similar to that of the six-port systems. But because of the simplicity of the three-probe theories. It is possible to realized the design of the three-probe system by using only analog circuits as reported in IEEE Trasactions on MTT as well as in the ARFTG conferences. The main advantage of this analog system is its real time measurement capacity. That is, it can measure and track in real time the variations of the real and the imaginary parts of the unknown complex impedance when this impedance is varying in real time. In this article, the author wish to report to the audience some experimental results of real-time tracking comparison measurements. These results were obtained by using simultaneously an HP 8410 automatic network analyzer and the current three-probe system. The 8410 is used with data taken directly from its analog output without going through its digital processing part. The quantitative difference between these two measured results is seen to be within a few percents while the qualitative variations of the two are exactly the same. The digitally treated outputs from any commercial network analyzer are usually more accurate but they are not measured continuously in real time. That is, it may not capture many important features of the varying unknown impedance when the impedance is varying very fast in real time.
On the total correctness of nondeterministic programs

Abstract For an arbitrary programming language with nondeterminism to be implementable, the existence of computation trees modelling the possible changes in state in the course of a computation is postulated. A general definition of what constitutes an execution method is then presented. Falling naturally out of these ideas is the correspondence between execution methods and total correctness, in that different properties are required of a program to be correct when different methods are adopted. We describe a variety of plausible methods of execution falling under the general definition and single out four particular ones. The arguments made are then illustrated by analysing the properties required by Dijkstra of guarded commands in view of these four methods. We conclude that a general approach such as that suggested here seems to be needed for dealing with programming languages and execution methods other than the particular ones treated by Dijkstra.
The Associations of Race/Ethnicity and Suicidal Ideation among College Students: A Latent Class Analysis Examining Precipitating Events and Disclosure Patterns

The aim of this paper was to examine precipitating events for suicidal ideation and how these experiences relate to disclosure in a diverse sample of college students were examined. Among non-Hispanic White students, relationship/academic problems were most associated with ideation. A romantic break-up increased the odds of getting help. Among racial/ethnic minority students, family/academic problems were most associated with ideation and students who reported multiple events were less likely to get help compared with those not reporting events. Future research should examine the reasons for interpersonal conflict among this high-risk group and their attitudes about help-seeking, and identify cultural norms associated with disclosure.
Histidine-Tryptophan-Ketoglutarate (HTK) is associated with reduced graft survival in deceased donor livers, especially those donated after cardiac death.

Single-center studies have reported that liver allograft survival is not affected by preservation in histidine–tryptophan–ketoglutarate (HTK) versus University of Wisconsin (UW) solution. We analyzed the UNOS database of liver transplants performed from July, 2004, through February, 2008, to determine if preservation with HTK (n = 4755) versus UW (n = 12 673) impacted graft survival. HTK preservation of allografts increased from 16.8% in 2004 to 26.9% in 2008; this was particularly striking among donor after cardiac death (DCD) allografts, rising from 20.7% in 2004 to 40.9% in 2008. After adjusting for donor, recipient and graft factors that affect graft survival, HTK preservation was associated with an increased risk of graft loss (HR 1.14, p = 0.002), especially with DCD allografts (HR 1.44, P = 0.025) and those with cold ischemia time over 8 h (HR 1.16, P = 0.009). Furthermore, HTK preservation was associated with a 1.2-fold higher odds of early (< 30 days) graft loss as compared to UW preservation (OR 1.20, p = 0.012), with a more pronounced effect on allografts with cold ischemia time over 8 h (OR 1.31, p = 0.007), DCD allografts (OR 1.63, p = 0.09) and donors over 70 years (OR 1.67, p = 0.081). These results suggest that the increasing use of HTK for abdominal organ preservation should be reexamined.
On the Differential Geometry of Flows in Nonlinear Dynamical Systems

In this paper, in order to investigate the relation between two flows given in two dynamical systems, a flow for an investigated dynamical system is called the compared flow and a flow for a given dynamical system is called the reference flow. A surface on which the reference flow lies is termed the reference surface. For a small time interval, the change rate of the normal distance between the reference and compared flows on the normal direction of the reference surface is measured by a new function (i.e., G-function). Based on the surface of the reference flow, the kth -order G-functions for the non-contact and lth -order contact flows in two different dynamical systems are introduced. Through the new functions, the geometric relations between two flows in two dynamical systems imposed in the same phase space are investigated without contact between the reference and compared flows. The compared flow passing through, returning back from and paralleling to the surface of the reference flow is discussed first. The tangency and passability for a compared flow to the surface of a reference flow with the lth -order contact are presented. The dynamics for the compared flow with such a contact to the reference surface is briefly addressed. Finally, the brief discussion of applications is given. The contact and tangential singularity between two flows are different. The kth -order contact of the compared flow to the reference surface indicates that the compared flow to the reference surface is of the kth -order singularity. However, the compared flow with the kth -order singularity to the reference surface does not mean that the compared flow to the reference surface is of the kth -order contact.Copyright © 2007 by ASME
N-acetoxy-2-acetylaminofluorene modification of a deoxyoligonucleotide duplex

The carcinogen N-acetoxy-2-acetylaminofluorene was reacted with d (CCACGCACC) to form a covalent adduct with attachment at the single guanine. The sample was purified, mixed 1:1 with d (GGTGCGTGG) and studied by thermal denaturation experiments. The Tm for the mixture was 35 +/- 3 degrees C, consistent with duplex formation. The method of continuous variation shows that the modified oligomer, d (CCACGAAFCACC), forms a 1:1 duplex with d (GGTGCGTGG). Circular dichroism spectra also indicate the formation of a duplex and suggest that the modified duplex has a left-handed conformation. Addition of the intercalating drug ethidium alters the CD spectrum of the modified duplex, resulting in a CD spectrum similar to that of ethidium bound to right-handed DNA.
Hilbert-Space-Valued Super-Brownian Motion and Related Evolution Equations

A stochastic partial differential equation in which the square root of the solution appears as the diffusion coefficient is studied as a particular case of stochastic evolution equations. Weak existence of a solution is proved by the Euler approximation scheme. The super-Brownian motion on [0, 1] is also studied as a Hilbert-space-valued equation. In this set up, weak existence, pathwise uniqueness, and positivity of solutions are obtained in any dimension d .
Accuracy of ACARS Wind and Temperature Observations Determined by Collocation

A collocation study of meteorological reports from commercial aircraft relayed through the Aircraft Communications, Addressing, and Reporting System (ACARS) has been performed to estimate standard deviations of observation errors for wind and temperature. ACARS observations were collected over an area in the western and central United States for a 13-month period, and this dataset was examined for pairs of reports within small spatial (#10 km) and temporal (#10 min) windows. The results showed an observation error of a single horizontal component of wind of 1.1 m s21 and 0.5 K for temperature above the boundary layer. Within the boundary layer, the rms difference of wind and temperature between aircraft was larger, presumably due to larger smallscale variations in the atmosphere and, in the case of wind, from aircraft maneuvers. These observation error estimates are valuable for use in data assimilation and for determination of forecast error from ACARS observation-minus-forecast differences. By comparing standard deviations at different levels, estimates of mesoscale variability at a 10-km scale in the lower troposphere were also calculated. These values (rms vector error of 1.8 ms 21 for wind, rms error of 0.5 K for temperature) can be interpreted as estimates of the 10-km lowertropospheric error of representativeness, also useful for data assimilation.
Education of Deaf and Partially Hearing Adults in Established Facilities for the Normally Hearing

It is impossible to estimate the waste of productivity caused by the failure to develop the potential abilities of the deaf and the hard of hearing populations. Expanding problems of increasing limited hearing populations and the demands of the professions, business, and industry for more highly trained persons must be met if the potential productivity of limited hearing adults is to be made available to society.Purpose of the ProjectThe purpose of the project was to determine the effectiveness of a comprehensive trade, technical, and academic program in existing educational facilities when certain techniques were introduced to help overcome the problem of impaired communication for the broad spectrum of limited hearing populations: the deaf (manual or oral), the partially hearing, the hard of hearing, and the multiply handicapped. The total enrollment for the three-year period, computed by adding up the enrollments for each academic year, was sixty-five.Specific goals.The specific goals included the foll...
Economic impact of inappropriate blood transfusions in coronary artery bypass graft surgery

Abstract purpose: In addition to historically important issues of blood inventory and blood safety, the costs of blood transfusion are anticipated to have an increasingly important impact on transfusion practices. To address this, we analyzed costs of blood support given to patients undergoing coronary artery bypass graft (CABG) surgery, along with costs of blood components whose transfusions were identified to be unnecessary. patients and methods: Blood components transfused as part of a previously reported national, multicenter audit of 30 adult patients each at 18 institutions undergoing primary, elective CABG surgery were reviewed. results: The range of blood purchase costs among institutions was broad, varying over twofold. The range of red cell units transfused varied over 10-fold, and the range of total components transfused varied over 40-fold. The number of blood components transfused unnecessarily represented 27% of all blood units transfused, ranging from 7% to 43% among institutions. Inappropriate transfusions accounted for 47%, 32%, and 15% of all platelet, plasma, and red cell units transfused. The mean institutional cost for all blood components transfused per patient was $397 ± $244. The cost per patient of components transfused inappropriately was 24% of this, or $96 ± $89 (mean ± SD). conclusion: These costs could be reduced with practice guidelines and quality improvement programs aimed at reducing the number of inappropriate transfusions.
Viscosity changes in a polymerized substrate due to the action of a hydrolytically depolymerizing enzyme.

Nachweis einer Enzymbildung nach Azotobacter-Infektion durch Phagen mit Spezifitat fur Kapsel-Depolymerisierung. Das Verfahren erfasst die Enzymaktivitat durch Registrierung der graduellen Veranderung der Viskositat des sich vorbereitenden Kapselstoffes.
Structural Memory in Pressure-Amorphized AlPO4

Molecular dynamics simulations reveal the mechanism of the structural memory effect in alpha-berlinite (AlPO(4)), where a single crystal transforms to an amorphous solid by compression and then reverts to the original crystalline structure upon release of pressure. The enhanced oxygen coordination around the aluminum atoms in AlPO(4) at high pressure leads to a mechanical instability that causes the phase transformation. The difference in the structural memory behavior between AlPO(4) and isostructural alpha-quartz, for which the pressure-induced amorphized phase is recoverable, can be attributed to the presence of the PO(4) units, which remain essentially four-coordinated even when severely distorted.
The Relation between Cost Shifting and Segment Profitability in the Defense‐Contracting Industry

We test the conjecture from prior research that defense contractors' excess profitability in the 1980s stemmed from their ability to shift common overhead costs to government contracts that typically allow cost reimbursement or price renegotiation (Rogerson 1992; Thomas and Tung 1992; Lichtenberg 1992). Although we confirm prior evidence that defense contractors enjoyed abnormally high profitability on their government work in the 1984–1989 period (a period of relatively low competition for defense contracts), we find no evidence that this excess profitability is attributable to cost shifting. In addition, we find no evidence that the Top 100 defense contractors (firms that likely wield above‐average market power) are able to use cost shifting to exploit a lack of competition in the industry. Our results suggest that, contrary to the conjectures in prior research, the unusually high profitability reported on government contracts in 1984–1989 is more likely attributable to nonaccounting explanations than t...
Bowtie plasmonic quantum cascade laser antenna

We report a bowtie plasmonic quantum cascade laser antenna that can confine coherent mid-infrared radiation well below the diffraction limit. The antenna is fabricated on the facet of a mid-infrared quantum cascade laser and consists of a pair of gold fan-like segments, whose narrow ends are separated by a nanometric gap. Compared with a nano-rod antenna composed of a pair of nano-rods, the bowtie antenna efficiently suppresses the field enhancement at the outer ends of the structure, making it more suitable for spatially-resolved high-resolution chemical and biological imaging and spectroscopy. The antenna near field is characterized by an apertureless near-field scanning optical microscope; field confinement as small as 130 nm is demonstrated at a wavelength of 7.0 mum.
Atomic force microscope observations of domains in fine-grained bulk lead zirconate titanate ceramics

This study describes sample preparation techniques that allow atomic force microscope observation of domains on the scale of tens of nanometers in fine-grained bulk lead zirconate titanate (PZT) ceramics. It is shown that carefully conducted light polishing and etching results in no significant disturbance to domain morphologies in hard PZT ceramics.
Vertical skin incisions and wound complications in the obese parturient.

Abstract Objective To examine the relationship between the type of skin incision and postoperative wound complications in an obese population. Methods A hospital-based perinatal database was used to identify women with a body mass index (BMI) of greater than 35 undergoing their first cesarean delivery. Hospital and outpatient medical records were reviewed for the following variables: age, insurance status, BMI, gestational age at delivery, birth weight, smoking history, prior abdominal surgery, existing comorbidities, preoperative hematocrit, chorioamnionitis, duration of labor and membrane rupture, dilation at time of cesarean delivery, type of skin and uterine incision, estimated blood loss, operative time, antibiotic prophylaxis, use of subcutaneous drains or sutures, endometritis, and length of stay. The primary outcome variable was any wound complication requiring opening the incision. Multiple logistic regression analysis was completed to determine which of these factors contributed to the incidence of wound complications. Results From 1994 to 2000, 239 women with a BMI greater than 35 undergoing a primary cesarean delivery were identified. The overall incidence of wound complications in this group of severely obese patients was 12.1%. Factors associated with wound complications included vertical skin incisions (odds ratio [OR] 12.4, P Conclusion Primary cesarean delivery in the severely obese parturient has a high incidence of wound complications. Our data indicate that a vertical skin incision is associated with a higher rate of wound complications than a transverse incision.
Frontline employee motivation to participate in service innovation implementation

Companies today face the challenge not only of designing innovative customer-focused service strategies to compete and grow but also of translating such strategies into results through successful execution. Experience and research demonstrate the difficulty of such an execution, but little research in marketing has focused on strategy implementation, particularly at the employee level. Prior research has suggested that frontline employee participation is critical to successful innovation implementation, especially in service contexts. We develop a theoretical model to investigate the complex role of motivation in engaging employee participation in service innovation implementation and test it with field data from a real-world context. The study contributes to motivation research in marketing by adapting and extending a hierarchical conceptualization from psychology that incorporates three levels of motivation: global, contextual, and situational. We also investigate the antecedents managers can control to increase employee motivation to participate in implementation efforts and subsequently to improve participation behaviors that are critical to the successful implementation of a customer service innovation.
Review article: high-dose aminosalicylates to induce and maintain remissions in ulcerative colitis

Sulfasalazine was the first aminosalicylate to be used for induction and maintenance therapy of ulcerative colitis (UC). Initial trials demonstrated a dose response that was compromised by dose-related intolerance. Recognition that the 5-aminosalicylic acid moiety (5-ASA, mesalazine) is the active ingredient of sulfasalazine has allowed the development of sulpha-free formulations of mesalazine and alternative azo-bond derivatives (olsalazine, balsalazide) that substantially reduce the dose-related (and allergic) consequences of the sulfapyridine moiety of sulfasalazine. Dose-ranging studies of mesalazine formulations for induction of remission have demonstrated increased efficacy of oral mesalazine up to 4-4.8 g/day, particularly in patients with more moderate disease activity. Combination therapy with oral and rectal mesalazine provide additional efficacy for patients with both distal and extensive colitis. The mesalazine formulations have dose-related benefits without dose-related side effects. In contrast, the azo-bond formulations are compromised by secretory diarrhoea at doses providing greater than 2-2.4 g/day of mesalazine. There are less data regarding dose-related benefits of aminosalicylates to maintain remissions in UC greater than 1.6 g/day of mesalazine, although the absence of dose-related side effects allows continuation of the same inductive dose through maintenance treatment without dose-related toxicity.
Grain-scale experimental validation of crystal plasticity finite element simulations of tantalum oligocrystals

Abstract In this work, the grain-scale elastoplastic deformation behavior of coarse-grained body centered cubic (BCC) tantalum was simulated using a crystal plasticity finite element method (CP-FEM) and compared to experimental measurements of intragranular strain and rotation fields. To mitigate the effects of unknown subsurface microstructure, tantalum tensile specimens with millimeter-sized grains provided nearly constant microstructure through the thickness of the tensile bar. Experimental validation was performed in three ways: (1) electron backscatter diffraction (EBSD) to map intragranular rotation, (2) high-resolution digital image correlation (HR-DIC) to map the surface strain field, and (3) surface profilometry to map the out-of-plane topographic distortion. To ensure a direct apples-to-apples comparison to experiments, the details of the initial microstructure and boundary conditions were carefully replicated in the model. The deformation predictions using this novel BCC CP-FEM model for tantalum agree reasonably well with the experimental measurements. In addition, the model successfully predicted the failure location of a specimen subjected to large plastic strains. Several model parameters were explored that influence the BCC CP-FEM predictions such as the mesh dependence, the choice of active slip planes in BCC metals and the assignment of initial crystal orientations.
Multi-scale simulation of oblique collisions of a droplet on a surface in the Leidenfrost regime

Abstract This work illustrates the phenomena of oblique impact of a water droplet on a hot solid surface in the Leidenfrost regime using a multi-scale model. The flow and heat transfer behavior on the droplet scale as described by the macroscopic model is solved using the finite volume method, together with the level set and the immersed boundary methods which quantify the variations of the gas–liquid and fluid–solid interfaces. A micro-scale vapor layer model is used to account for the resistance effect of the vapor layer generated by the film-boiling evaporation. These two models are coupled in each time step, and solved concurrently. Based on this multi-scale model, the effect of the impact velocity is investigated numerically. The droplet shape and impact parameters such as momentum loss and contact time calculated from the present model are compared with the experimental results obtained from the literature. A good agreement is seen between the simulated and the experimental results.
Assessing Dimensionality of a Set of Item Responses--Comparison of Different Approaches.

This study compares the performance of three methodologies for assessing unidi-mensionality: DIMTEST, Holland and Rosenbaum's approach, and nonlinear factor analysis. Each method is examined and compared with other methods on simulated and real data sets. Seven data sets, all with 2,000 examinees, were generated: three unidimensional and four two-dimensional data sets. Two levels of correlation between abilities were considered:ρ=3 andρ=. 7. Eight different real data sets were used: Four of them were expected to be unidimensional, and the other four were expected to be two-dimensional. Findings suggest that all three methods correctly confirmed unidimensionality but differed in their ability to detect lack of unidimensionality. DIMTEST showed excellent power in detecting lack of unidimensionality; Holland and Rosenbaum's and nonlinear factor analysis approaches showed good power, provided the correlation between abilities was low.
Comparison of patients undergoing laser vaporization of the prostate versus TURP using the ACS-NSQIP database.

Comparison of patients undergoing laser vaporization of the prostate versus TURP using the ACS-NSQIP database
A basic education programme in Africa: The people's own?

Abstract This paper examines the issue of community ownership with reference to an adult literacy and basic education programme in NW Zaire. After a discussion of community ownership, stressing the need for local control and relevance to local needs, it outlines the context and development of the programme in NW Zaire and considers the degree to which ownership is manifested in the design of technical aspects of the programme and its structures. Finally it identifies some key issues for continued progress, particularly the shape of partnerships between external agencies and strengthened local structures.
Evaluating the Role of Blood Collection Centers in Public Health: A Status Report

Blood centers have a central role in the community through recruitment and donation, and these community interactions enable blood centers to have a critical role in public health. Some public health initiatives are inherent in the blood center, such as providing human immunodeficiency virus educational material, whereas other initiatives have been actively created, such as cardiovascular screening, as a means to increase blood donor rates and increase the blood center's community interaction. These public health initiatives have been inconsistently practiced by blood collection centers over many years. An understanding of the current literature and exploring the potential role of blood centers in public health, while considering cost and value of these programs, are necessary for blood centers to evaluate the value of implementing these programs. The studies do not support a significant improvement in donor health or significant increase in donation rates through these public health initiatives. However, no study published thus far has been comprehensive enough or carried out long enough to adequately evaluate the value of providing health initiatives to donors.
Postnatal development of 2ƒ1−ƒ2 otoacoustic emissions in pigmented rat

Distortion-product emissions at 2f1-f2 were measured in developing, pigmented rats to determine the characteristics of the functional onset and maturation of these emitted responses. Distortion-product testing was conducted on postnatal days 12, 14, 18, 21, 24, 28, and 51. The geometric-mean frequencies of the primaries were tested at one-half octave intervals, between 4 and 11.3 kHz. No emissions were detected on postnatal day 12; however, by day 14, emissions were measured at geometric-mean frequencies between 5.7 and 11.3 kHz, but not at 4 kHz. By the 18th postnatal day, all animals had measurable emissions at 4, 5, 7, 8, and 11.3 kHz. Both the functional onset and maturation of high- to midfrequency emissions developed before those elicited by lower-frequency primaries. Response/growth or input/output functions for the higher frequencies exhibited 'adult-like' properties that included an increase in maximum amplitude and 'saturation' at high levels of stimulation by the third to fourth postnatal week. Maturation of the lower-frequency responses progressed at a slower rate. These results differ somewhat from those reported previously for the neonatal albino rat. However, the present findings were based upon a wider frequency range of primary tones, lower levels of acoustic stimulation, and a measuring system with a significantly lower noise floor. These results are consistent with documented periods of the anatomical maturation of the rat outer hair-cell system and establish a functional 'baseline' for future studies utilizing agents that damage the developing cochlea.
Constrained querying of multimedia databases: issues and approaches

Copyright 2001 Society of Photo-Optical Instrumentation Engineers. One print or electronic copy may be made for personal use only. Systematic electronic or print reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited. http://dx.doi.org/10.1117/12.410976
Long-term complications of radiotherapy confronting the head and neck surgeon.

Despite significant growth in the knowledge and application of radiation physics to human cancer therapy, there continue to be significant complications from such therapy. Selected cases are presented and discussed to illustrate the long-term complications of radiotherapy which may arise when dealing with cancer in the head and neck.
Spectroscopic modeling of the CO2+ A2Πu→X2Πg (110-010) Renner-Teller bands in electron beam fluorescence of carbon dioxide

Abstract Improvements have been made to a spectroscopic model of the electron beam fluorescence (EBF) spectra from the CO 2 + A 2 Π u → X 2 Π g electronic transition of the (100-000), (200-100) and (300-200) bands through the inclusion of the (110-010) Renner-Teller bands. The (010) vibrational state of the CO 2 molecule is thermally excited at temperatures near 300 K based on an analysis of the vibrational partition function for this molecule. The excitation and emission processes for these Renner-Teller bands were modeled with dipole moments. The inclusion of these Renner-Teller bands into the spectroscopic model produces an improved fit to the measured fluorescence spectrum between 337 nm and 339 nm. This improved model provides for a more accurate measurement of the rotational temperature using the EBF technique.
Macrocycle complexation chemistry. 37. The isolation and crystallographic characterization of the U4+ and UO2+ extraction complexes [(H5O2)(dicyclohexano-24-crown-8)]2[U02Cl4]⁗MeOH and [(H5O2) (dicyclohexano-24-crown-8)]2[UCl6]⁗MeOH

The reaction of dicyclohexano-24-crown-8 with UCl4 in 3/1 THF:MeOH under anhydrous conditions and with exposure to air, resulted in the isolation of the hydronium ion complexes, [(H5O2)(dicyclohexano-24-crown-8)]2[UO2Cl4]-MeOH and [(H5O2)(dicyclohexano-24-crown-8)]2[UCI6]-MeOH. The [UO2Cl4]2− complex crystallizes in the monoclinic space group,P21/n, witha = 15.200(8),b = 26.565(9),c = 16.977(8)A, β = 95.89(6)° andDcalc = 1.40 g cm−3 forZ = 4 formula units. A finalR value of 0.051 was obtained utilizing 5913 independent observed [Fo ≥ 5σ(Fo)] reflections. One ether is complexed by an ordered H5Oinf2sup+ ion, while the second crown ether is hydrogen bonded to a disordered H5Oinf2sup+ ion. The [UCl6]2− complex is tetragonal,P4/n, with (at −150°C)a = 16.320(4),c = 12.542(2)A andDcalc = 1.47 g cm−1 forZ = 2. A finalR value of 0.038 was obtained utilizing 2466 observed reflections. The anion resides on a four-fold axis and the crown ether cation around a crystallographic two-fold axis. The H5Oinf2sup+ion is disordered into two orientations within the macrocycle cavity. All three crystallographically independent crown ether environments in these two structures have essentially identical conformations.
The prediction of drug solubilities in polymers

Prevision pour 6 polymeres et 16 solutes. L'equation de correlation log P (polymere-eau)=a log P(octanol-eau)+b. Determination a partir de la solubilite de l'eau dans la masse du polymere
Rescue of a 7502-Nucleotide (49.3% of Full-Length) Synthetic Analog of Respiratory Syncytial Virus Genomic RNA

Abstract A cDNA was constructed to encode an internally-truncated version of negative-sense genomic RNA (vRNA) of respiratory syncytial virus (RSV) containing (in 3′ to 5′ order) the 3′ vRNA leader region, the complement of the open reading frame for bacterial chloramphenicol acetyl transferase (CAT) under the control of RSV gene-start and gene-end signals, an intergenic nucleotide, the complete L gene including the gene-start and gene-end signals, and the 5′ vRNA trailer region. The encoded vRNA analog (RSV-CAT-L) would be 7502 nucleotides (nt) in length, 49.3% of the complete 15,222-nt parental vRNA. RSV-CAT-L vRNA was synthesized in vitro from Hga l-digested cDNA and transfected into RSV-infected cells. The vRNA was "rescued" such that it was expressed to yield CAT and was packaged into particles that could be passaged to express CAT in fresh cells. The efficiency of rescue was greatly improved by a single nucleotide substitution in the leader region that had been found to increase the efficiency of rescue and passage of the previously described 935-nt RSV-CAT vRNA. Compared to the 8-fold smaller RSV-CAT vRNA, and adjusted to molar equivalence of transfected RNA, RSV-CAT-L vRNA was 119- to 347-fold less efficient in expressing CAT upon transfection, whereas RSV-CAT-L vRNA containing the above-mentioned nucleotide substitution was 15.8-fold less efficient.
The veterans affairs continuous improvement in cardiac surgery study

The Department of Veterans Affairs Cardiac Surgery Consultants Committee is responsible for reviewing the quality of cardiac surgical treatment at the 43 Veterans Affairs cardiac surgical centers where these procedures are performed. It does so by reviewing both the unadjusted and risk-adjusted operative mortality data and the incidence of perioperative complications. These data are reviewed by the committee semiannually, and the overall summary and hospital-specific data are shared with the individual cardiac surgical program directors. Paper audits and site visits are performed when indicated by increased unadjusted and risk-adjusted operative mortality. Constructive criticism is shared with the program director and medical center administration. The relative risk of death for numerous patient risk factors has been estimated, and is now used in prospective clinical decision making. During the 7-year period that risk-adjusted outcomes have been utilized, there has been an overall significant reduction in the observed-to-expected operative mortality ratio. Although many factors could have contributed to this, including continually improving surgical techniques, it is also likely that part of this improvement has occurred because of the continuous feedback of these quality improvement data to our cardiothoracic surgeons and cardiologists.
Complications of Supramid Orbital Implants

PurposeTo determine the incidence and risk factors of complications associated with Supramid orbital implants.MethodsA retrospective chart review was performed to document complications in a series of 41 patients receiving Supramid implants during orbital reconstruction or fracture repair. Implant s
Source processes of large ( M≥6.5) earthquakes of the Southeastern Caribbean (1926 1960)

We have conducted body waveform modeling studies of 13 historic earthquakes to provide a better understanding of the long-term spatial and temporal pattern of seismicity and deformation within a region extending from Barbuda, Lesser Antilles, to Cumana, Venezuela. Our results suggest that shallow earthquakes (<50 km deep) along the South American-Caribbean plate margin reflect right-lateral and extensional deformation. Intermediate depth events (≥100 km) show left-lateral strike-slip motion beneath the Paria peninsula of Venezuela. In the Lesser Antilles the 1960 Barbuda and 1946 Martinique earthquakes appear to be interplate thrust events, however the greatest moment release in the region has occurred at intermediate depths as a mixture of normal and strike-slip faulting, generally along trends oblique to the arc. The deformation rate estimated from the seismic moment release between 1926 and 1960 is only 1 to 10% of the estimated plate convergence rate for the region.