cssi/SciSciGPT-SciSciNet huggingface dataset:
A nonlinear growth mechanism in size structured population dynamics

Abstract The dynamics of a population depend upon the sizes and/or maturity of the individual members of the population. In many species (the most popular examples are fish and trees) the growth and maturation rate of an individual is controlled by the ability of that individual to obtain necessary resources. For such a species, individual growth rates depend upon the overall condition of the population. The purpose of this paper is to develop a continuous model with size structure, in which individual growth rates are not known a priori. An individual's size depends not only upon its age, but upon the history of the general population during its past life. The resulting model is a nonlinear variation of the classical McKendrick-Von Foerster model. The mathematical descriptions of growth processes which originate in the biological literature can be used as constitutive equations in our model. In some cases, such substitutions allow the model to be reduced to a system of ordinary differential equations.
Black Scholes, As Compared to Observed Prices: An Empirical Study

The Black Scholes option pricing model has been put to extensive application both in research and in actual market place. However, the inputs for the model are generally obtained from the stock market which is considered less efficient than the options market. This leads to a difference in calculated price and observed price. This paper studies the bias empirically.
Comparison of cyclic nucleotide specificity of guanosine 3',5'-monophosphate-dependent protein kinase and adenosine 3',5'-monophosphate-dependent protein kinase.

Abstract Guanosine 3′,5′-monophosphate-dependent protein kinase (cyclic GMP-dependent protein kinase) and adenosine 3′,5′-monophosphate-dependent protein kinase (cyclic AMP-dependent protein kinase) exhibited a high degree of cyclic nucleotide specificity when hormone-sensitive triacylglycerol lipase, phosphorylase kinase, and cardiac troponin were used as substrates. The concentration of cyclic GMP required to activate half-maximally cyclic dependent protein kinase was 1000- to 100-folds less than that of cylic AMP with these substrates. The opposite was true with cyclic AMP-dependent protein kinase where 1000- to 100-fold less cyclic GMP was required for half-maximal enzyme activation. This contrasts with the lower degree of cyclic nucleotide specificity of cyclic GMP-dependent protein kinase of 25-fold when histone H2b was used as a substrate for phosphorylation. Cyclic IMP resembled cyclic AMP in effectiveness in stimulating cyclic GMP-dependent protein kinase but was intermediate between cyclic AMP and cyclic GMP in stimulating cyclic. AMP-dependent protein kinase. The effect of cyclic IMP on cyclic GMP-dependent protein kinase was confirmed in studies of autophosphorylation of cyclic GMP-dependent protein kinase where both cyclic AMP and cyclic IMP enhanced autophophorylation. The high degree of cyclic nucleotide specificity observed suggests that cyclic AMP and cyclic GMP activate only their specific kinase and that crossover to the opposite kinase is unlikely to occur at reported cellular concentrations of cyclic nucleotides.
Cooperative learning instructional methods for CS1: Design, implementation, and evaluation

Cooperative learning is a well-known instructional technique that has been applied with a wide variety of subject matter and a broad spectrum of populations. This article briefly reviews the principles of cooperative learning, and describes how these principles were incorporated into a comprehensive set of cooperative learning activities for a CS1 course. In each activity, specific roles are assigned to group members in order to highlight important concepts and to enhance the overall functioning of the group. The group processing is followed by a whole-class debriefing led by the instructor, which works in tandem with the group activity to help students improve their understanding of the material. The effectiveness of these cooperative learning activities was assessed in a series of educational research studies which spanned three academic years and included two different instructors. The results of these studies show statistically significant benefits from the cooperative learning approach, both overall and for a broad range of subgroups of students. The article concludes with suggestions for faculty members who may want to use these cooperative learning activities in the classroom, or to develop their own activities along similar lines.
Electrokinetic characterization of highly sulfonated polystyrene model colloids

Abstract Highly sulfonated polystyrene latex particles were prepared by a two-stage “shot-growth” emulsion polymerization process in the absence of emulsifier. Sodium styrene sulfonate (NaSS) was used as an ionic co-monomer to produce a series of latex particles with nearly the same particle size but with different surface charge densities. The cleaning process used, including centrifugation and redispersion with the aid of strong sonication, proved to exert a strong influence on the final surface charge density of the particles. The electrokinetic behavior of three latex samples with surface charge densities between 13.9 and 19.4 μC cm−2 was very similar, with constant values of the electrophoretic mobilities for pH between 4 and 11 and a maximum in the electrophoretic mobility values when the ionic strength was 5 · 10−2M NaCl. This last result was found even after a systematic and long latex cleaning process, and after treatment at high electrolyte concentrations. The experimental results for the electrokinetic characterization of these highly sulfonated polystyrene latexes suggest that the surface of the particles are covered by a layer of oligomers or polymer chains which are chemically bound to the surface, and which control the colloidal properties of this type of latex.
The role of hormone receptors and GTP-regulatory proteins in membrane transduction

Cell membrane receptors for hormones and neurotransmitters form oligomeric complexes with GTP-regulatory proteins and inhibit the latter from reacting with GTP. Hormones and neurotransmitters act by releasing the inhibitory constraints imposed by the receptors, thus allowing the GTP-regulatory proteins to interact with and control the activity of enzymes such as adenylate cyclase. This theory may apply generally to membrane signal transduction involving surface receptors.
Endogenous circadian system and circadian misalignment impact glucose tolerance via separate mechanisms in humans

Glucose tolerance is lower in the evening and at night than in the morning. However, the relative contribution of the circadian system vs. the behavioral cycle (including the sleep/wake and fasting/feeding cycles) is unclear. Furthermore, although shift work is a diabetes risk factor, the separate impact on glucose tolerance of the behavioral cycle, circadian phase, and circadian disruption (i.e., misalignment between the central circadian pacemaker and the behavioral cycle) has not been systematically studied. Here we show—by using two 8-d laboratory protocols—in healthy adults that the circadian system and circadian misalignment have distinct influences on glucose tolerance, both separate from the behavioral cycle. First, postprandial glucose was 17% higher (i.e., lower glucose tolerance) in the biological evening (8:00 PM) than morning (8:00 AM; i.e., a circadian phase effect), independent of the behavioral cycle effect. Second, circadian misalignment itself (12-h behavioral cycle inversion) increased postprandial glucose by 6%. Third, these variations in glucose tolerance appeared to be explained, at least in part, by different mechanisms: during the biological evening by decreased pancreatic β-cell function (27% lower early-phase insulin) and during circadian misalignment presumably by decreased insulin sensitivity (elevated postprandial glucose despite 14% higher late-phase insulin) without change in early-phase insulin. We explored possible contributing factors, including changes in polysomnographic sleep and 24-h hormonal profiles. We demonstrate that the circadian system importantly contributes to the reduced glucose tolerance observed in the evening compared with the morning. Separately, circadian misalignment reduces glucose tolerance, providing a mechanism to help explain the increased diabetes risk in shift workers.
Hormonal Effects on Spermidine Levels in Male and Female Reproductive Organs of the Rat

Levels of spermidine in male and female reproductive organs were determined after castration and after castration plus steroid hormone administration. Spermidine concentrations in the rat ventral prostate and seminal vesicle decreased after castration. Testosterone treatment of castrated rats restored the spermidine concentration to normal levels in the ventral prostate but increased the concentration in the seminal vesicle above normal levels. The early changes in amounts of spermidine and RNA in the castrate rat seminal vesicle in response to testosterone showed a very high correlation. The ductus deferens and seminal vesicle fluid contained low levels of spermidine. Estrogen treatment caused a significant increase in spermidine concentration in the ovariectomized rat uterus 24 hr after intravenous injection. In view of the reported in vitro effects of spermidine on nucleic acid and ribosomal structure, these observations suggest a relationship between spermidine and the synthesis of RNA and protein in ...
EEG theta and alpha responses reveal qualitative differences in processing taxonomic versus thematic semantic relationships

Despite the importance of semantic relationships to our understanding of semantic knowledge, the nature of the neural processes underlying these abilities are not well understood. In order to investigate these processes, 20 healthy adults listened to thematically related (e.g., leash-dog), taxonomically related (e.g., horse-dog), or unrelated (e.g., desk-dog) noun pairs as their EEG was recorded. The data were analyzed using both event-related potentials (ERP) and event-related spectral perturbation (ERSP) analyses. The spatiotemporal ERP and ERSP results were analyzed further with principal component analysis (PCA). When comparing unrelated to related word pairs, the expected N400 effect was confirmed, as well as differences in theta and alpha oscillations. When comparing thematically and taxonomically related word pairs, the ERP revealed no significant differences, but the ERSP did. Specifically, theta power increased over right frontal areas for thematic versus taxonomic relationships and alpha power increased over parietal areas for taxonomic versus thematic relationships. The different oscillatory patterns over different brain regions suggest that thematic and taxonomic relationships engage distinct neural processes. Specifically, thematic relationships engage memory processes, while taxonomic relationships may require additional inhibitory or attention processes.
Viability, preference, and coalitions in the french election of 1951

Elections as a social choice institution have, of course, received intensive theoretical consideration in Public Choice. However, attention has largely been focused on situations that can be represented as n-person noncooperative games among candidates or parties, with particular emphasis on two-person constant-sum games. While mathematical facility has had much to do with these theoretical developments, the prevalence of the two-party system in the United States perhaps has also had an influence. Yet multiparty systems are in presence in much of the world. Multicandidate primaries already common in the U.S. have been further encouraged by recent proposals for proportional representation in Presidential primaries. The voter in a multicandidate or multiparty race is faced with a complex decision task. Viability as well as preference must be taken into account (McKelvey and Ordeshook, 1972; Kramer, 1968). Thus the voter may rationally vote for a candidate other than that candidate whose "position" is "closest" to the voter's.1 Moreover, in addition to considering the impact of his vote on eventual governing
Hyperglycemic, hyperosmolar syndrome in feline diabetics: 17 cases (1995–2001)

Objective: The purposes of this study were to characterize the hyperglycemic, hyperosmolar syndrome (HHS), also known as nonketotic hyperosmolar diabetes, in cats; to determine the prevalence of HHS in the diabetic cat population in the emergency room; to document the outcome in cats with HHS; and to identify any predisposing factors or predictors of survival. Design: Retrospective study. Setting: An emergency service at a veterinary teaching hospital located in a major metropolitan area. Animals: The case records of 17 cats with hyperglycemic, hyperosmolar syndrome presenting from 1995 to 2001 were evaluated. An additional 37 cats with diabetic ketoacidosis and 80 cats with diabetes mellitus served as comparison groups. Interventions: None. Measurements and main results: Signalment, history, physical examination findings, clinico-pathologic data, concurrent disease, and outcome were recorded. Hyperglycemic, hyperosmolar syndrome was seen in older cats that were often long-standing diabetics receiving insulin for many months. Client concerns included polydipsia, polyuria, and lethargy. Neurologic and respiratory signs occurred frequently. Evaluation at presentation revealed profound dehydration, lactic acidosis, and azotemia. Serious concurrent diseases that likely contributed to the development of the HHS crisis were diagnosed in 88% (15/17) of the HHS cats. The most common concurrent diseases were renal failure, respiratory compromise, infection, congestive heart failure, neoplasia, and gastrointestinal tract disease. Pancreatitis and hepatic disease did not occur frequently in this diabetic cat population. Sixty-five percent of HHS cats did not survive the initial hospitalization, with most dying or being euthanized within 10 hours of presentation. The long-term survival rate was low (12%). Conclusions: HHS is a serious life-threatening form of diabetic crisis and cats with HHS often have other severe systemic diseases. Cats with diabetes and concurrent disease, especially renal failure and congestive heart failure, are at increased risk of HHS and should be closely monitored for signs of crisis. The mortality rate for HHS cats is high.
Predictions of the masses of highly neutron-rich light nuclei

A simple mass equation is derived and is shown to provide a good description of the masses of the recently measured ${T}_{Z}=\frac{5}{2}$ nuclei in the $s\ensuremath{-}d$ shell. A comparison is made with the method of Garvey et al. and predictions of masses and of the stability of neutron-excess light nuclei are given for both methods.NUCLEAR STRUCTURE Derived mass equation based on shell model; compared predictions with method of Garvey et al.
In Vivo Imaging of Vesicular Monoamine Transporters in Human Brain Using [11C]Tetrabenazine and Positron Emission Tomography

: The pharmacokinetics of [11CJtetrabenazine, a high-affinity radioligand for the monoamine vesicular transporter, were determined in living human brain using in vivo imaging by positron emission tomography (PET). The radiotracer showed high brain uptake and rapid washout from all brain regions with relatively slower clearance from regions of highest concentrations of monoamine vesicular transporters (striatum), resulting in clear differential visualization of these structures at short intervals after injection (10–20 min). As the first human PET imaging study of a vesicular neurotransmitter transporter, these experiments demonstrate that external imaging of vesicular transporters forms a new and valuable approach to the in vivo quantification of monoaminergic neurons, with potential application to the in vivo study of neurodegenerative disorders such as Parkinson's disease.
Effective interventions and implementation strategies to reduce adverse drug events in the Veterans Affairs (VA) system

Background: Adverse drug events (ADEs) account for considerable patient morbidity and mortality as well as legal, operational and patient care costs. In Veterans Affairs (VA) hospitals in the USA, all serious adverse events and “potential” adverse events are reviewed using root cause analysis (RCA). This study characterised RCA reports associated with ADEs to determine what actions VA RCA teams took to reduce the number or severity of ADEs, and to evaluate which actions were effective in doing so. Methods: Every medication-related RCA submitted to the VA National Center for Patient Safety in the fiscal year 2004 (143 reports), and one medication-related aggregated RCA from each facility (111 reports covering 4834 ADEs) were reviewed and coded. Facilities were interviewed about specifics of their reports and the results of their interventions. Results: The commonest classes of medication for which ADEs were reported were narcotics, chemotherapy, and diabetic and cardiovascular medications. The most common types of ADE were “wrong dose”, “wrong medication”, “failed to give medication”, and “wrong patient”. 993 actions were taken to address these ADEs, the majority (75.7%) of which were reported to be fully implemented. Improvements in equipment and improving clinical care at the bedside were associated with reports of improved outcomes (p = 0.018, and p = 0.017 respectively), and training and education were negatively correlated with reports of improved outcome (p = 0.005). Improving the process of medication order entry through the use of alerts or forcing functions was positively correlated with reports of improved outcomes (p = 0.022). Leadership support and involving staff were associated with higher implementation rates (p = 0.001 and p = 0.010, respectively). Conclusions: Changes at the bedside and improvement in equipment and computers are effective at reducing ADEs. Well-organised tracking and support from leadership and staff were characteristics of facilities successful at improving outcomes. Training without action was associated with worse outcomes.
A model of visuomotor mechanisms in the frog optic tectum

Abstract This paper describes a model of information-processing mechanisms in the frog visual system. The model delimits a class of specific mechanisms. One of these mechanisms, which utilizes cells like the “sameness” and “newness” cells reported in the frog optic tectum, is presented. Results of a computer simulation demonstrate the mechanism's performance.
Design of a semi-active knee prosthesis

Current state-of-the-art prostheses for transfemoral amputees operate exclusively through controlled damping or through fully powered gait imitation. The passive devices cannot restore a natural gait, and the active devices are large and inefficient. This paper summarizes the design of a new semi-active prosthetic knee that combines the proven safety and power efficiency of a passively damped hydraulic device with the improved gait and advanced mobility of a fully active device.
Role of Cystitis Cystica et Glandularis and Intestinal Metaplasia in Development of Bladder Carcinoma

Objectives Cystitis cystica et glandularis (CCEG) and intestinal metaplasia (IM) have been suggested to represent precursors of bladder adenocarcinoma. The relationship between these entities and the subsequent development of bladder carcinoma remains unclear. Methods We retrospectively evaluated the association among florid CCEG, IM, and bladder carcinoma. The records and imaging findings of patients with a pathologic diagnosis of florid CCEG and/or IM were reviewed for a concurrent or future diagnosis of bladder carcinoma or pelvic lipomatosis. Results We identified 136 patients from 1982 to 2006 with florid CCEG (n = 117) or IM (n = 19). Of the 117 patients with CCEG, a subset was identified with concurrent mucinous adenocarcinoma (n = 1; Conclusions Both florid CCEG and IM can be identified in benign bladder specimens or in conjunction with bladder carcinoma. Although IM can be associated with a concurrent diagnosis of carcinoma, we found no evidence that it increases the future risk of malignancy and our findings do not support a recommendation for surveillance cystoscopy in such patients. No association was identified between either CCEG or IM and pelvic lipomatosis.
A more efficient residue arithmetic implementation of the FFT

After 20 years, the FFT remains restricted in its real time capabilities. To overcome this throughput obstacle, fast residue arithmetic units are studied based on several recent innovations in the field of complex finite rings. A dedicated machine is designed which makes use of these new results and is compared to conventional FFT designs. Using high speed semiconductor memory to implement the required residue arithmetic mappings, speed and complexity metrics of a basic FFT unit are shown to be improved. However, the derived architecture and arithmetic introduce a new and challenging set of magnitude scaling problems. They are resolved with the result being an integrated residue arithmetic FFT system capable of supporting very high real time data rates.
The Role of Postnatal Growth Pattern in the Production of Facial Morphology

We apply a new morphometric technique in a comparative study of facial growth patterns in three primate species: Macaca fascicularis, Cercopithecus aethiops, and Cebus apella. This method, Euclidean distance matrix analysis (Lele, 1991, Am. J. Phys. Anthropol. 85:407-418; Lele and Richtsmeier, 1991, Am. J. Phys. Anthropol. 86:415-428), enables a three-dimensional description of differences in facial geometries and statistical testing of differences among forms. We adapt the method to enable comparison of growth patterns among species and to produce hypothetical forms by joining the immature morphology of a given species with the growth pattern of another species. Our results demonstrate the unique properties of postnatal growth patterns for the three species considered
Microbial production of amphotericin B-3H and the synthesis of its sodium desoxycholate (carboxyl-14C) complex and methyl-14C-ester.

Amphotericin B-3H with a specific radioactivity in excess of 4 μCi/mg was produced by fermentation of Streptomyces nodosus IMRU 3694 in a complex medium, using acetate-3H as a precursor. The medium employed gave a production yield of 2.5-3.5 mg/ml of amphotericin B. The most efficient incorporation of acetate-3H occurred when the precursor was added at 24 hours after inoculation. It was observed, that the amount of amphotericin A co-produced in the fermentation broth with amphotericin B was significantly reduced by the addition of ethanol to the production medium. Complete inhibition of amphotericin A production was achieved at a level of 2% ethanol in the fermentation medium without an appreciable effect on the yield of amphotericin B. Methanol, 1-propanol, 2-propanol and 1-butanol lowered the yield of both antibiotics indiscriminately. The syntheses of amphotericin B-3H-Na desoxycholate (carboxyl-14C) complex and amphotericin B-3H methyl 14C-ester are also described.
Work in progress - testing right from the start

Writing syntactically correct code and understanding algorithm development are two essential skills mastered by most introductory computer science students. Another important component of professional programming is thorough testing to verify correct design and accurate coding; however this topic is frequently covered with less emphasis than it deserves in the core programming curricula. In this paper we describe instructional software that we are developing to support introductory level programming students in collaboratively and incrementally developing test cases for the class libraries they implement, as well as to automatically validate their implementations. This software is structured as an Internet application with a simplified user interface that allows distributed generation of a common library of test cases as well as remote testing of each student's individual implementation. By integrating testing and validation into the earliest stages of programming instruction, we anticipate that students will develop a better understanding of not only the syntax of the programming languages they are using but, more importantly, a deeper understanding of the semantics of the code they author and better success in debugging initial versions of their program solutions. Furthermore, using an Internet based infrastructure allows students to become familiar with having different aspects of the program development process itself performed by different (teams) of individuals, each of whom might be geographically distributed: an important practical component of global software engineering. A fully functional on-line version of our software is expected by the end of Summer 2007 and Human Subjects Protocol approval is expected for Fall 2007 evaluation of the effectiveness of our software in instructing introductory level programming students.
Power system design for massive parallel computer systems

Large mainframe computers are slowly dying off, as massively parallel computer systems are replacing them to become the way of the future which offers scalability, redundancy and system availability not possible previously. These new computers require power systems that are equally capable in scalability, redundancy and availability. This paper explores the system availability and MTBF requirements of distributed high power, paralleled, fault-tolerant power systems, which are necessary to match the needs of parallel computer systems within the next five years. >
Free Will And The Dialectic Of Selfhood: Can One Make Sense Of A Traditional Free Will Requiring Ultimate Responsibility?

For four decades, I have been developing a distinctive view of free will according to which agents are required to be ultimately responsible for the creation or formation of their own wills (characters and purposes). The aim of this paper is to explain how a free will of this traditional kind —which I argue is incompatible with determinism— can be reconciled with modern developments in the sciences and philosophy. I address criticisms that a nondeterminist free will of this kind does not allow sufficient agent control, reduces to mere chance or randomness, fails to account of moral responsibility, and cannot be reconciled with modern science; and I relate such a free will to the nature of the self or person by developing what I call a "dialectic of selfhood."
Circulating levels of neopterin and indicators of nutritional status in hemophiliac patients with and without HIV infection

Abstract Neopterin, a product of activated macrophages/monocytes, was studied in 20 HIV(+) and 20 HIV(−) hemophiliac patients aged 3–31 years. None of the HIV(+) patients had clinical symptoms of AIDS, and most were asymptomatic in CDC stage II. In the overall population and age matched patients, neopterin levels were significantly higher in HIV(+) than in HIV(−) patients and they increased during the 10 months of median follow-up time. As expected, the mean levels of CD4 cells, CD4CD8 cell ratio, absolute lymphocyte counts, and indicators of nutritional status (albumin, prealbumin) were significantly lower (p
Applications of CFD Analysis in Arc-Jet Testing of RCC Plug Repairs

Computational simulations are used as an integral part of arc-jet testing from the planning stages of the arc-jet experiments through post-test analysis for increasingly complex test configurations. This paper reports two applications of such analysis: an analysis for reinforced carbon-carbon plug repair tests conducted in a NASA Ames arc-jet facility, and a feasibility study of full-scale Shuttle wing leading edge plug repair tests in the facility, where four possible configurations are investigated. For the plug tests, arc-jet flows over wedge models, with and without plugs mounted, and plugs differing in step height and diameters, are simulated. For the feasibility study, arc-jet flows of four test configurations are simulated, and based on the predicted test environments of these configurations, one is recommended for future arc-jet tests of full-scale plug repair. The present analyses comprise computational simulations of the nonequilibrium flowfield in the facility nozzle and test box as well as the flowfield over the models. These examples further demonstrate the value of computational simulations in planning and analysis of arc-jet tests.
Reassessing the Role of Housing in Community-Based Urban Development

Abstract In this article, we use a random sample of urban community development corporations (CDCs) to determine whether distinct types exist and, if so, to estimate their prevalence in the industry. The typical urban CDC has a diversified portfolio of economic and social development activities, including community organizing, and is likely to have a housing development program, although not necessarily a large one because relatively few are high producers. Large‐scale housing producers, defined in the study as having produced at least 500 units during the previous 10 years, comprise 18 percent of CDCs. A large organizational capacity, an affiliation with national intermediaries, the training of staff and the adoption of computers, the length of executive directors’ tenure, and the share of funding devoted to housing programs are the most important factors increasing the odds that a CDC will belong to the group of high producers.
Interacting-string picture of the fermionic string

On etablit le formalisme d'integration fonctionnelle, on deduit le modele analogue et on indique en termes generaux comment la transformation conforme au Z plan peut etre effectuee
Autonomously Moving Local Nanoprobes in Heterogeneous Magnetic Fields

Different strategies of navigation in heterogeneous magnetic fields are investigated using natural and synthetic autonomously moving micro- and nanonavigators on top of a magnetic garnet film with uniaxial anisotropy creating a dense stripe domain structure. The use of ferromagnetic navigators leads to dynamic frustration, but synergy is achieved between the autonomous motion and magnetic orientation of paramagnetic navigators. The use of differently magnetized ferromagnetic and paramagnetic nanonavigators enables one to change from a roving to a guided motion. These different modes of motion can be utilized for distinct processes, such as the delivery and distribution of molecular cargo attached to synthetic navigators.
Characteristics of U.S., Japanese, and British Commonwealth universities offering education in agriculture

The purposes of this study were: (1) to compare universities that do and do not provide training in agriculture in the United States, Japan, and the British Commonwealth, and (2) to examine similarities and differences among those nations with respect to characteristics of agricultural universities. In all these nations, universities that offer training in agriculutre are significantly larger than universities that do not. In the United States and Japan, but not in the British Commonwealth, agricultural universities are characterized by a significantly greater technical emphasis. In Japan alone agricultural universities are significantly more affluent than other universities. A hierarchical grouping of the United States, Japan, and 17 British Commonwealth nations on similarities among their agricultural universities yielded three broad clusters. Those appear to reflect, respectively, U.S., British, and African approaches to agricultural higher education.
Interpenetrating polymer networks of poly(carbonate-urethane) and polyvinyl pyridine

Simultaneous interpenetrating polymer networks (IPN's), pseudo IPN's, and liner blends of aliphatic poly(carbonate-urethane) (PCU) and polyvinyl pyridine (PVP) have been prepared and characterized by DSC, DMA, and TEM. The full IPN's of PCU and PVP had a single phase morphology only above 50 wt % PCU, as determined by both DSC and DMA and confirmed by transmission electron microscopy (TEM). However, in both pseudo IPN's of PCU and PVP and in their linear blends there exist multiple glass transitions and melting points seen by DSC and DMA indicating phase incompatibility. The full IPN's exhibited superior ultimate mechanical properties and solvent resistance as compared to the pseudo IPN's, liner blends, and the pure crosslinked PCU and PVP networks.
Molecular epidemiology and emergence of worldwide epidemic clones of Neisseria meningitidis in Taiwan

Meningococcal disease is infrequently found in Taiwan, a country with 23 million people. Between 1996 and 2002, 17 to 81 clinical cases of the disease were reported annually. Reported cases dramatically increased in 2001–2002. Our record shows that only serogroup B and W135 meningococci have been isolated from patients with meningococcal disease until 2000. However, serogroup A, C and Y meningococci were detected for the first time in 2001 and continued to cause disease through 2002. Most of serogroup Y meningococcus infections localized in Central Taiwan in 2001, indicating that a small-scale outbreak of meningococcal disease had occurred. The occurrence of a meningococcal disease outbreak and the emergence of new meningococcal strains are of public health concern. Neisseria meningitidis isolates from patients with meningococcal disease from 1996 to 2002 were collected and characterized by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). The genetic relatedness and clonal relationship between the isolates were analyzed by using the PFGE patterns and the allelic profiles of the sequence types (STs). Serogroups A, B, C, W135, Y, and non-serogroupable Neisseria meningitidis were, respectively, responsible for 2%, 50%, 2%, 35%, 9%, and 2% of 158 culture-confirmed cases of meningococcal disease in 1996–2002. Among 100 N. meningitidis isolates available for PFGE and MLST analyses, 51 different PFGE patterns and 30 STs were identified with discriminatory indices of 0.95 and 0.87, respectively. Of the 30 STs, 21 were newly identified and of which 19 were found in serogroup B isolates. A total of 40 PFGE patterns were identified in 52 serogroup B isolates with the patterns distributed over several distinct clusters. In contrast, the isolates within each of the serogroups A, C, W135, and Y shared high levels of PFGE pattern similarity. Analysis of the allelic profile of the 30 STs suggested the serogroup B isolates be assigned into 5 clonally related groups/ clonal complexes and 7 unique clones. The ST-41/44 complex/Lineage 3, and the ST-3439 and ST-3200 groups represented 79% of the serogroup B meningococci. In contrast, isolates within serogroups A, serogroup W135 (and C), and serogroup Y, respectively, simply belonged to ST-7, ST-11, and ST-23 clones. Our data suggested that serogroup B isolates were derived from several distinct lineages, most of which could either be indigenous or were introduced into Taiwan a long time ago. The serogroup A, W135 (and C), and Y isolates, respectively, belonged to the ST-7, ST-11, and ST-23, and the represented clones that are currently the major circulating clones in the world and are introduced into Taiwan more recently. The emergence of serogroup A, C and Y strains contributed partly to the increase in cases of meningococcal disease in 2001–2002.
Refractive shift in pseudophakic eyes during the second decade of life.

Purpose To evaluate the refractive shift in pseudophakic eyes of children after their 10th birthday. Setting Storm Eye Institute, Charleston, South Carolina, USA. Design Case series. Methods One eye of each patient with at least 2 refractions at a minimum of a 1-year interval after the 10th birthday was analyzed. Results One hundred fourteen pseudophakic eyes (114 patients) were identified. The mean initial refraction was −0.65 diopter (D) ± 2.27 (SD) and the mean final refraction, −1.78 ± 2.82 D. The mean shift in refraction was −1.13 ± 1.36 D; the mean shift in refraction per year was −0.30 ± 0.38 D. Postoperative refraction could be predicted by regression analysis (P Conclusion A myopic shift in refraction continued in children after 10 years of age, which has important implications for the use of multifocal IOLs in preteens and teenagers and for IOL power selection. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.
The Uneven Performance of Arizona's Charter Schools.

Arizona enrolls a larger share of its students in charter schools than any other state in the country, but no comprehensive examination exists of the impact of those schools on student achievement. Using student-level data covering all Arizona students from 2006 to 2012, we find that the performance of charter schools in Arizona in improving student achievement varies widely, and more so than that of traditional public schools (TPS). On average, charter schools at every grade level have been modestly less effective than TPS in raising student achievement in some subjects. But charter schools that closed during this period have been lower performing than schools that remained open, a pattern that is not evident in the traditional public sector.
Compact and super broadband volumetric folded dipole antenna for mobile applications

The purpose of this study is to provide a miniaturized volumetric folded dipole antenna with ideal electrical and mechanical characteristics such as broadbandness, good impedance matching, compactness (light weight, small sized, cheap), and rigidness; compared to other competitors such as biconical antennas and others. Our proposed antenna is competent at low frequencies especially in the HF range where there is a need for small sized antennas.
Lutein Bioavailability Is Higher from Lutein-Enriched Eggs than from Supplements and Spinach in Men

Lutein may be protective against diseases such as age-related macular degeneration (ARMD). At present, data regarding bioavailability of lutein from various sources are insufficient. Healthy men (n = 10) participated in an intervention study with a crossover design. After a 2-wk washout period during which they consumed a low-carotenoid diet, the men were administered 1 of 4 lutein doses (lutein supplement, lutein ester supplement, spinach, and lutein-enriched egg) for 9 d. All lutein doses provided 6 mg lutein except for the lutein ester dose, which provided 5.5 mg lutein equivalents. Serum samples were collected from fasting subjects on d -14, 1 (baseline), 2, 3, and 10 and analyzed for changes in lutein concentration. Triacylglycerol-rich lipoproteins (TRL) were separated from postprandial blood samples (0-24 h) after the first lutein dose and analyzed for lutein concentration. Subjects completed all 4 treatments of the study in random order. Results from repeated-measures 1-way ANOVA showed that the baseline and dose-adjusted lutein response in serum was significantly higher after egg consumption than after lutein, lutein ester, and spinach consumption on d 10. There was no significant difference in TRL response. In conclusion, the lutein bioavailability from egg is higher than that from other sources such as lutein, lutein ester supplements, and spinach. The lutein bioavailability from lutein, lutein ester supplements, and spinach did not differ. This finding may have implications for dietary recommendations that may decrease the risk of certain diseases, e.g., ARMD.
Bio-physical ocean modeling in the Gulf of Mexico

The Naval Research Laboratory (NRL) Oceanography Division has implemented a 1/25o horizontal-resolution numerical ocean model for the Gulf of Mexico (GOM). The model domain encompasses the entire GOM extending from 18o to 31o North and from 77o to 98o West. The physical formulation is based on the Naval Coastal Ocean Model (NCOM) configured with a 40 level σ-z vertical structure: 19 terrain-following σ (sigma) levels at the top of the water column, and 21 z (depth) levels at the bottom. The terrain-following levels, reaching from the surface to about 137 meters, allow higher vertical resolutions for resolving mixed layer/shallow waters, while the z-levels are used in the stratified ocean. The ocean bathymetry is constructed from the NRL 2-minute database with the coastline set at a depth of 2 meters. The physical model is one-way coupled to a 13-component ecosystem (biogeochemical) model [Chai et. al., 2002, 2003, 2007] that includes nutrients, two classes of plankton, as well as O and CO2. The current configuration is tailored, but not limited to, real-time (RT) prediction; providing nowcasts (current state of the ocean) and up to 120-hour forecasts for the region. In this configuration, the model receives (initial) boundary information from the operational 1/8o Global NCOM, and it is forced by 3-hourly 1/2o momentum and heat fluxes from the Naval Operational Global Prediction System (NOGAPS). The NCOMGOM model assimilates daily surface/subsurface temperature and salinity generated by the Modular Ocean Data Assimilation System (MODAS), which regresses satellite derived Sea Surface Temperature (SST) and Sea Surface Height (SSH) data to obtain T&S synthetic profiles. The model was initialized on January 1, 2009 from the operational 1/8o Global NCOM physical state and from the World Ocean Atlas 2005 and Carbon Dioxide Information Analysis Center (CDIAC) biogeochemical fields. Results from the real-time NCOMGOM nowcasting/forecasting ocean modeling system are compared and evaluated against in-situ and remotely sensed observations, which include bio-optical products processed by the NRL Ocean Color Section. Google Earth/Ocean is used as a platform for viewing the model results interactively and dynamically in real-time. Initial assessment of the model prediction skill is presented along with future plans for improvements and enhancements. The suitability of the system as a tool for decision management is discussed, outlining processes localized to particular areas such as hypoxia, dead zones, wetland loss and degradation, harmful algal blooms, as well as tropical storms and related issues that affect all coastal regions of the Gulf of Mexico.
Relevance of External Beam Dose–Response Relationships to Kidney Toxicity Associated with Radionuclide Therapy

The importance of the kidney as a dose-limiting organ is likely to increase as smaller molecular vectors and radiometals become more commonly used in targeted radionuclide therapy. Data derived from kidney irradiation by external-beam therapy (XRT) indicate that the kidney is radiosensitive. The features of radiation nephropathy seen post-treatment appear similar between local XRT, total-body irradiation (TBI), and radionuclide therapy. For uniform kidney irradiation, tolerance doses appear to be approximately 15–17 Gy in 2 Gy fractions for local XRT and probably less than this (~12 Gy in 2 Gy fractions) when radiation is delivered systemically as TBI in the context of bone marrow transplant protocols. Animal studies indicate that the linear quadratic (LQ) model with an α/β parameter of 1.5–3 Gy seems to adequately describe the XRT fractionation sensitivity of kidney for doses per fraction down to approximately 1 Gy, but may underestimate the effectiveness of fraction sizes less than this. Animal studies ...
Rise/fall time enhancement of the spallation neutron source Linac LEBT chopper system

The Spallation Neutron Source (SNS) Linac Low Energy Beam Transport (LEBT) chopper system provides fast chopping of the H- ion beam in the LEBT structure. Four identical pulsed power supplies (pulsers) create a series of ± 3.0 kV pulses to the four deflection electrodes floating on the focusing voltage of -45kV. Each pulser is connected to the electrode through the network which consists of high voltage (HV) cables, a blocking capacitor, HV feed-through connectors, current-limiting resistors and transient voltage suppressors. Effective beam chopping requires minimal rise/fall times of the rectangular HV pulses on the load. In the present configuration these values are approximately 130-140 ns. Methods of reducing rise/fall times on the LEBT electrodes are discussed. Results of simulation and comparative measurements of the old and upgraded system on the test stand are presented. Furthermore, the effect of these changes on reliability degradation caused by arcing in the LEBT structure is discussed.1
Intraocular lens power calculation after myopic excimer laser surgery: Selecting the best method using available clinical data

Purpose To compare the results of methods to calculate intraocular lens (IOL) power after myopic excimer laser surgery. Setting G.B. Bietti Foundation-IRCCS, Rome, Italy. Design Prospective interventional case series. Methods Eyes were classified into 4 groups: Group 1 (preoperative keratometry available, refractive change known), Group 2 (preoperative keratometry available, refractive change uncertain), Group 3 (preoperative keratometry unavailable, refractive change known), and Group 4 (preoperative keratometry unavailable, refractive change unknown). The IOL power was calculated by 19 methods. The median absolute error in refraction prediction and the percentage of eyes with a refraction prediction error within ±0.50 diopter (D) were calculated. Results In Group 1 (n = 30), the Savini, Seitz/Speicher/Savini, and Masket methods provided the lowest median absolute error (0.29 D, 0.35 D, and 0.34 D, respectively), with more than 70% of eyes within ±0.50 D of the predicted refraction. In Group 2 (n = 16), the Seitz/Speicher method achieved the best result (median absolute error 0.37 D), with 75% of eyes within ±0.50 D of the predicted refraction. In Group 3 (n = 18), the Masket method provided the lowest median absolute error (0.24 D), with 72.2% of eyes within ±0.50 D of the predicted refraction. In Group 4 (n = 6), the Shammas no-history method had the lowest median absolute error (0.31 D), with 83% of eyes within ±0.50 D of the predicted refraction. Conclusion Intraocular lens power can be accurately calculated in post-laser surgery eyes when the preoperative corneal power and refractive change are known and when they are not. Financial disclosure Dr. Hoffer receives book royalties for IOL Power and formula royalties from all manufacturers using the Hoffer Q formula to ensure it is programmed correctly. No other author has a financial or proprietary interest in any material or method mentioned.
Regulation of Na+-K+-ATPase activity in kidney proximal tubules: involvement of GTP binding proteins

This study evaluates the involvement of GTP-dependent regulatory proteins (G-proteins) in the regulation of Na+-K+-ATPase activity in proximal convoluted tubule (PCT) segments. Single PCT segments were dissected from rat kidney and permeabilized to allow nucleotides and medium free access to the interior of the cell. A GDP analogue that blocks GTP-dependent activation of the G-protein, GDP beta S (400 microM) significantly inhibited PCT Na+-K+-ATPase activity when Na in the medium (Nam) was greater than or equal to 70 mM. The inhibition was attenuated when Nam was 55 and 35 mM and was no longer significant when Nam was 25 mM. GDP beta S had no inhibitory effect on the activity of purified Na+-K+-ATPase. A nonhydrolyzable GTP analogue, GppNHp (50 microM) significantly increased Na+-K+-ATPase activity when Nam was 25 and 35 mM, but not when Nam was 55-140 mM. Dopamine (DA) and DA1 plus DA2 agonists significantly inhibit Na+-K+-ATPase activity. DA inhibition was competitively abolished by GppNHp. In PCT segments from rats pretreated with pertussis toxin, DA and DA1 plus DA2 agonist inhibition of Na+-K+-ATPase activity was abolished. In PCT segments from rats pretreated with cholera toxin, basal Na+-K+-ATPase activity was increased, but DA significantly inhibited Na+-K+-ATPase activity. Na+-K+-ATPase activity in PCT segments is regulated via a G-protein that stimulates Na+-K+-ATPase activity and a DA-activated pertussis toxin-sensitive G-protein that inhibits Na+-K+-ATPase activity.(ABSTRACT TRUNCATED AT 250 WORDS)
Trastuzumab for all? A decision analysis examining tradeoffs between efficacy and cardiac toxicity of adjuvant therapy in HER2 positive breast cancer

6022 Background: Early results from three randomized trials showed that adjuvant trastuzumab (T) results in significant reduction in recurrence rates in high risk HER2 positive breast cancer patien...