cssi/SciSciGPT-SciSciNet huggingface dataset:
Sickle Cell Disease in the Adolescent Female

Sickle cell disease (SCD) is an inherited blood disorder that causes affected individuals to produce an abnormal hemoglobin that results in frequent pain events, organ damage, and early mortality. Disease- specific treatments include hydroxyurea, L-glutamine, voxelator, crizanlizumab, and blood transfusions. Hematopoietic stem cell transplant is curative but limited due to a requirement for a matched-related donor in most cases. Adolescence can be a difficult time for females affected by SCD. Pain events may increase in frequency, due to decline in protective fetal hemoglobin levels, medication noncompliance, hormone effects, or progression of the chronic illness. Some patients may develop chronic, daily pain in adolescence, from repeated pain crises, or opioid-induced hyperalgesia. Transitioning from pediatric to adult providers may be a source of anxiety, and developing independence from parents is a challenge. Gynecological issues include a need to avoid estrogen containing birth control products due to the hypercoagulable state of SCD, difficulties in diagnosing dysfunctional uterine bleeding, and the high-risk nature of pregnancy in an individual with SCD. Individuals with SCD have high rates of psychological complications, including depression, anxiety, and body image dysfunction.
Potential Unintended Consequences of National Infectious Disease Screening Strategies in Deceased Donor Kidney Transplantation: A Cost-Effectiveness Analysis

In order to counter the lack of sufficient kidney donors, there has been interest in expanding the utilization of organs from increased infectious-risk donors. Negative nucleic acid testing of increased infectious-risk organs has been shown to increase their use as compared to only enzyme-linked immunosorbent assay negativity. However, it is not known how the expanded use of nucleic acid testing on a national scale might affect total donor utilization. The objective of this paper was to determine if a national screening policy requiring the use of nucleic acid testing in both increased infectious-risk and non-increased infectious-risk renal transplant donors would increase the donor organ pool. This study used decision-tree analysis to determine the cost-effectiveness of four US national screening policies based on an increasingly expansive use of nucleic acid testing for increased infectious-risk and non-increased infectious-risk kidneys. Parameters were taken from the literature. All costs were reported in 2020 US dollars using a Medicare payer perspective and a life-time horizon. The use of nucleic acid screening solely for increased infectious-risk organs was the dominant strategy. Our results were robust to deterministic and probabilistic sensitivity analyses. One of the main driving factors of cost-effectiveness was the false-positive rate of nucleic acid testing. Before implementing nucleic acid screening outside of increased infectious-risk organs, its false-positivity rate should be directly studied to ensure that its use does not detrimentally affect transplantation numbers, quality-adjusted life-years, and costs.
A CLINICAL CHALLENGE OVERCOME BY HIS BUNDLE PACING

Pseudo-pacemaker syndrome from PR prolongation can cause symptoms due to AV dyssynchrony. 55-year-old female with Non-Hodgkin's lymphoma s/p mantle radiation therapy presents with sudden and abrupt worsening of baseline exertional dyspnea. Workup with transthoracic echocardiogram, coronary
Bridge and Boundary: The Maritime Connections of Colonial Arequipa, Peru

European empires heavily relied on maritime connections for their expansion and operations. In the Andean region, where Spanish colonialism had a distinct urban character, maritime connections were emplaced in a tripartite arrangement or city-port axes. In this article, I show that the city of Arequipa, in southwestern Peru, differed from this pattern. There emerged instead a capillary arrangement of semi-specialized maritime links between the city and the Pacific Ocean. I also explore the conditions that favored this arrangement, including the positioning of Arequipa within southern trade networks, the city’s unique location, and the presence of an important port at Arica.
Inactivation of the central nucleus of the amygdala reduces the effect of punishment on cocaine self-administration in rats

Continued cocaine use despite the negative consequences is a hallmark of cocaine addiction. One such consequence is punishment, which is often used by society to curb cocaine use. Unfortunately, we know little about the mechanism involved in regulation by punishment of cocaine use. The fact that cocaine addicts continue to use cocaine despite potentially severe punishment suggests that the mechanism may be impaired. Such impairment is expected to critically contribute to compulsive cocaine use. This study was aimed at testing the hypothesis that the central nucleus of the amygdala (CeN) plays a critical role in such regulation. To this end, rats were trained to press a lever to self-administer cocaine under a chained schedule: a response on one lever (cocaine-seeking lever) led to access to the other lever (cocaine-taking lever), on which a response was reinforced by cocaine and cues. Thereafter, responses on the seeking lever were punished by footshock with a probability of 0.5. Cocaine self-administration (SA) was significantly suppressed by punishment in an intensity-dependent manner. Interestingly, rats trained with daily 6-h (extended access) but not 2-h (limited access) sessions showed resistance to the lower intensity of punishment. Inactivation of the CeN induced a robust anti-punishment effect in both groups. These data provided evidence that the CeN is a critical neural substrate involved in regulation by punishment of cocaine SA. Rats with a history of extended cocaine SA appeared to be less sensitive to punishment. The decreased sensitivity could result from the neuroplastic changes induced by extended cocaine SA in the CeN.
A Survey of Techniques to Estimate the Uncertainty in Material Parameters

When estimating parameters for a material model from experimental data collected during a separate effects physics experiment, the quality of fit is only a part of the required data. Also necessary is the uncertainty in the estimated parameters so that uncertainty quantification and model validation can be performed at the full system level. The uncertainty and quality of fit of the data are many times not available and should be considered when fitting the data to a specified model. There are many techniques available to fit data to a material model and a few of them are presented in this work using a simple acoustical emission dataset. The estimated parameters and the affiliated uncertainty will be estimated using a variety of techniques and compared.
A stochastic model of the formation and survival of lunar craters: VI. Initial depth, distribution of depths, and lunar history

Abstract The distribution of depths of lunar craters can be predicted by a model which takes into account the formation, obliteration, filling, and isostatic readjustment of craters. These theoretical studies suggest more efficient ways of estimating the initial depth-diameter relationship, assuming that the deepest craters are the most recent. The estimated initial depth H ( χ ) of continental craters of diameter χ (larger than 15 km) is H ( χ ) = 1.0 χ 0.40 and for craters in the maria is H ( χ ) = 0.75 χ 0.50 , where H ( χ ) and χ are in kilometers. As the difference is not significant, there is no reason to believe that many craters in the continents and maria have had different modes of origin. If the crater-forming and crater-filling rates are exponentially decreasing functions of time, and if isostatic readjustment of craters can be neglected, then the distribution of H ( χ ) − Y is a truncated Weibull distribution, where Y is the observed depth of a crater of diameter χ. This distribution gives good fits to empirical crater depth distributions based on extensive unpublished data of G. Fielder. The crater-filling mean lifetime is about 1.5 times as long on the continents, and 1.7 times as long on the maria, as the crater-forming mean lifetime. This implies that crater-filling mechanisms on the Moon were of longer duration than crater-forming mechanisms, especially on the maria. It is also possible to obtain some information about the underlying distribution of crater diameter χ. If the meteoroidal impact hypothesis were correct, this distribution would be an inverse power law with index γ >, and should be the same on continents and maria. From the data we estimate γ = 2.18 on the continents but γ = 2.66 on the maria. Because of very large uncertainties in the estimates this discrepancy is not significant. The available statistical data are still not adequate to establish the validity or otherwise of the impact hypothesis.
A Review of “Prehospital Emergency Care, Seventh Edition”

Brady's Prehospital andEmergency Care has been one of the most frequently used texts in EMT courses for many years. The seventh edition is the third version based on the 1994 EMT-Basic National Sta...
Choquet Integrals and OWA Criteria as a Natural (and Optimal) Next Step after Linear Aggregation: A New General Justification

In multi-criteria decision making, it is necessary to aggregate (combine) utility values corresponding to several criteria (parameters). The simplest way to combine these values is to use linear aggregation. In many practical situations, however, linear aggregation does not fully adequately describe the actual decision making process, so non-linear aggregation is needed. From the purely mathematical viewpoint, the next natural step after linear functions is the use of quadratic functions. However, in decision making, a different type of non-linearities are usually more adequate than quadratic ones: non-linearities like OWA or Choquet integral that use min and max in addition to linear combinations. In this paper, we explain the empirically observed advantage of such aggregation operations.
Magneto-optic measurements with a sagnac interferometer

Abstract We have developed a novel technique for measuring the Faraday effect and the magneto-optic Kerr effect. In a Sagnac interferometer, two optical beams follow identical paths in opposite directions. Effects which break time-reversal symmetry, like magneto-optic effects, will cause destructive interference between the two beams. By measuring the phase shift between circular polarization states reflected from a magnetized sample, we measure the polar magneto-optic Kerr effect to an accuracy of 2 μrad, with a spatial resolution of 2 μm. The interferometric technique provides a number of advantages over conventional polarizer methods, including insensitivity to linear birefringence, the ability to completely determine the magnetization vector in a region, and the ability to sensitively measure magneto-optic effects without an external field.
Component procurement and end product assembly in an uncertain supply and demand environment

In this paper, we examine a multi-product, multi-component, procurement and assembly problem with both supply and demand uncertainties. We explicitly model the uncertainty using a stochastic program that facilitates procurement and assembly decisions. We present a stochastic linear programming model of the problem which we solve using its deterministic equivalent with a finite number of scenarios. We show that the systems performance, i.e. total cost, depends on the order lead time, L, and the assembly lead time Q, only through their sum . We illustrate the impact of on system performance with numerical experiments. Also, we illustrate that, in some cases, increasing supplier capacity can worsen system performance. In addition, we identify the key cost drivers that need attention from managers in the manufacturing industry, when there is limited knowledge of future demand and component availability.
Unwitnessed sulphonylurea poisoning in a healthy toddler

Glipizide is a second generation sulphonylurea used in the treatment of Type 2 diabetes mellitus. It exerts its hypoglycaemic effect by stimulating insulin secretion from the pancreatic beta cells [8]. Regular-release glipizide has a peak effect at 1–3 h, half life of 7 h and duration of action of 12–24 h [12]. In overdose, sulphonylureas can cause prolonged and profound hypoglycaemia. Without treatment, it can progress in severity and may cause permanent neurological injury or even death [26]. Hypoglycaemia has been reported in children who have ingested even a single sulphonylurea tablet [2, 12, 24, 28]. Young children, particularly toddlers, are especially vulnerable to accidental ingestion of medications due to a combination of curiosity about their environments, increasing independent mobility, imitation of adult behaviours and inability to discriminate safe from unsafe products [16]. Grandparent caregiver is a known risk factor for unintentional paediatric exposures to medications referred to as “the granny syndrome” [16]. We report a case of severe hypoglycaemia secondary to hyperinsulinism caused by unwitnessed accidental ingestion of glipizide involving a grandparent caregiver, managed without the use of diazoxide or octreotide.
Class of optimal damage-resistant communication nets

It is shown that the product Kn×Kn of the complete graph Kn with itself is an optimal damage-resistant net in the Boesch and Thomas sense, i.e. Kn×Kn is optimally invulnerable to disconnection by either vertex or line removal.
Internal Gear Strains and Load Sharing in Planetary Transmissions: Model and Experiments

This paper presents results of a comprehensive experimental and theoretical study to determine the influence of certain key factors in planetary transmissions on gear stresses and planetary load sharing. A series of tests are conducted on a family of planetary gear sets, and strains are recorded at various locations on the outer diameter and gear tooth fillet of the ring gear. Pinion position errors are introduced as a representative key manufacturing tolerance, and the resultant changes in the planetary behavior are observed. The experimental data is compared to the predictions of a state-of-the-art multi-body contact analysis model — ‘Gear System Analysis Modules’ (GSAM). This model is capable of including the influences of a number of system-level variables and quantifying their impact on gear strains. The model predictions are shown to compare well with the measured strain at the ring gear outer diameter and tooth fillet. GSAM predictions of planet load sharing are then used to quantify the influence of pin hole position errors on the 3, 4, 5, and 6 planet test gear sets. These predictions also agree well with the planet load sharing experiments presented in a companion paper [20].Copyright © 2007 by ASME and General Motors
The Declining Role of NASDAQ Market Makers

We compare the liquidity providing behavior of NASDAQ market makers in 2010 to their behavior in 2004. We examine how frequently market makers are at the inside quote, what market and stock specific factors influence market makers’ behavior, and the relation between market maker participation and intraday bid-ask spread patterns. We observe a decrease in the percent of the trading day dealers’ quote at the inside, a decline in the number of market makers, and a decrease in the influence market makers have on intraday spread patterns. The results suggest that the role of NASDAQ market makers declines over time.
Maximal mean/standard deviation ratio in an undiscounted MDP

A stationary policy in an MDP (Markov decision process) induces a stationary probability distribution of the reward from each initial state. The problem analyzed here is maximization of the mean/standard deviation ratio of the stationary distribution. In the unichain case, a solution is obtained via parametric analysis of a linear program having the same number of variables and one more constraint than the formulation for gain-rate optimization. The same linear program suffices in the multichain case if the initial state is an element of choice. The easier problem of maximizing the mean/variance ratio is mentioned at the end of the paper.
The molecular pathobiology of stored neutrophils

Abstract The neutrophil is a short-lived cell because it has limited biosynthetic capacity to repair and maintain its component parts. Studies on neutrophil storage show generalized defects involving energy metabolism, phagocytosis, microbial killing, chemotaxis, membrane receptors, microtubules, microfilaments, and stimulus—response coupling. Some storage conditions are more detrimental to certain functions than others, e.g. cold induces a severe chemotactic defect. Thus, room temperature storage is preferable to refrigerated storage. For optimal storage, it is necessary to have sufficient glucose in the medium and to maintain an adequate pH. During storage, a dismantling of the functional integrity of the cell occurs with the most highly integrated functions being lost initially, while primitive functions are retained the longest. With minor exceptions, the generalized metabolic, structural, and functional defects noted in stored neutrophils are not peculiar to storage but most likely mirror the inexorable in vivo programmed senescence of the neutrophil.
Clump 1 - An unusual molecular cloud complex near the Galactic center

The properties of the (C-12)O and (C-13)O emission from Clump I, a complex of molecular clouds which shows the largest noncircular velocities of any molecular material known in the Milky Way, are studied. Observations of the J = 1-0 rotational transitions of the above molecules are reported, and the large-scale distribution and kinematics of the molecular gas in the direction of Clump I are discussed. The small-scale structure is described based on one arcmin resolution of (C-13)O data. Physical properties of the molecular material are derived, and the dynamics of the Clump I clouds are discussed in the context of their stability against Galactic tidal forces. It is concluded that all the clouds in the complex are gravitationally bound, although their outer envelopes may be tidally disrupted by the Galactic potential. The relative motion of the clouds is qualitatively similar to giant molecular cloud complexes in spiral arms of the outer Galactic disk, but the velocities are higher.
Hybrid bacterial and enzyme membrane electrode with nicotinamide adenine dinucleotide response

Abstract A mixture of intact bacterial cells and an enzyme extract is used in conjunction with an ammonia gas sensor to construct a new type of hybrid membrane electrode. The hybrid electrode measures the coenzyme NAD+ by means of a biocatalytic sequence that produces ammonia in stoichiometric amounts. Calibration plots are linear from approximately 2.5 x 10-4 to 2.5 x 10-3M NAD+ with a slope of -49 mv/decade. The electrode has a useful lifetime of at least one week. The present work demonstrates that hybrid electrodes can be developed for the measurement of substances which require multi-step sequences to form final electroactive products and, thus, extends the range of applicability of bioselective membrane electrodes.
Double trouble: HIV latency and CTL escape.

HIV can enter a state of latency that allows it to persist for decades in antiretroviral drug-treated patients. In a recent Nature paper, Deng et al. (2015) show that this latent reservoir also contains a large number of cytotoxic T lymphocyte escape mutants, presenting another challenge to HIV cure efforts.
Engineering pricing incentives for efficient bandwidth utilization in LambdaGrids

The ability to reserve network bandwidth is a critical factor for the success of high-performance grid applications. Reservation of lightpaths in dynamically switched optical networks facilitates guaranteed bandwidth. However, reservation of bandwidth can often lead to bandwidth fragmentation which significantly reduces system utilization and increases the blocking probability of requests. An interesting approach to mitigating this problem is to induce quasi-flexibility in the user requests. A smart scheduling strategy can then exploit this quasi-flexibility and optimize bandwidth utilization. However, there has to be an incentive for flexibility from the user's perspective as well. In this paper, we explore how the Network Service Provider (NSP) can influence user flexibility by dynamically engineering pricing incentives. Ultimately, user flexibility will lead to efficient network utilization, reduce the price for the users, and increase the revenue for the NSP.
Measures of accuracy and performance of diagnostic tests

Abstract Diagnostic tests are integral to the practice of veterinary cardiology, any other specialty, and general veterinary medicine. Developing and understanding diagnostic tests is one of the cornerstones of clinical research. This manuscript describes the diagnostic test properties including sensitivity, specificity, predictive value, likelihood ratio, receiver operating characteristic curve. Methods Review of practical book chapters and standard statistics manuscripts. Results Diagnostics such as sensitivity, specificity, predictive value, likelihood ratio, and receiver operating characteristic curve are described and illustrated. Conclusion Basic understanding of how diagnostic tests are developed and interpreted is essential in reviewing clinical scientific papers and understanding evidence based medicine.
Love and confidence in protection as two independent systems underlying intimate relationships.

This comment provides theoretical and empirical support for 2 independent systems, love and security of attachment, that have often been confounded in the literature. These systems have different functions, different emotions, a different distribution among the primates, and a different pattern of theoretically expected sex differences. Evidence for this distinction can be found in M. D. S. Ainsworth's (1967) original empirical studies and the recent work of Phillip R. Shaver and his colleagues (K. A. Brennan, C. L. Clark, & P. R. Shaver, 1998), as well as data reported here. The Experiences in Close Relationships Inventory (ECR) was administered to 239 undergraduates. Participants also filled out the Nuturance/Love (LOV) scale from the Interpersonal Adjective Scale Big Five-Revised to explore expected negative correlations between love as measured in standard personality tests and the avoidance factor of the ECR. As predicted, women scored lower on the Avoidance scale and higher on the LOV scale, whereas there were no gender differences in security in close relationships. As predicted, LOV was negatively correlated with avoidance but not with security.
Second Quantization, Projective Modules, and Local Gauge Invariance

Bundles and bundle structures have gained wide currency in modern approaches to certain topics in quantum physics, significant applications appearing in connection with gauge theories (e.g., Atiyah and Jones, 1978), theories of geometric quantization (e.g., Kostant, 1970; Sniatycki, 1974), and in numerous other contexts. In this paper we argue that such structures can already be discerned in the most elementary notions of second quantization, albeit in disguised form. An examination of the methods traditionally used by physicists in dealing quantum mechanically with systems exhibiting an infinite number of degrees of freedom reveals, almost from the outset, the implicit use of module structures over algebras of functions (Section 2). By making these structures explicit and adapting some results of perturbation theory we arrive at an association between bare particles and finitely generated projective modules (Sections 3 and 4). In particular, rank one modules emerge naturally, for algebraic reasons, as the appropriate descriptors of bosons in this association. (This provides a possible setting for the development of standard geometric quantization theory.) As a first application of the formalism we show the existence of phononlike excitations in general many-fermion systems. When these ideas are further specialized (local) gauge theoretical notions arise in a natural way out of a consideration of the bundles obtained via Swan's theorem. These theories emerge moreover equipped with an interpretation linked directly to the geometrical entities associated with the underlying bundles. Thus for example in the line bundle (or rank one) case,
Resolving lithospheric and sub-lithospheric contributions to helium isotope variations in basalts from the southwestern US

Abstract The 3 He/ 4 He ratios of continental basalts and their peridotitic xenoliths delimit the (U + Th)/ 3 He evolution of continental lithospheric mantle, but their interpretation is complicated by the potential for differential mobility of He with respect to lithophile elements. In this study we report 3 He/ 4 He ratios of 5.5–7.7 R A for olivines separated from young basalts in the southwestern US. Helium isotope ratios are lowest in samples that exhibit Th and Pb isotope evidence for derivation from an enriched source in the lithospheric mantle that has remained unmodified since ∼ 1.7 Ga. There is a strong, positive correlation between 3 He/ 4 He and e Nd in southwestern US lavas, suggesting a time-integrated affinity between light rare earth- and (U + Th)/ 3 He-enrichment in the underlying Proterozoic lithospheric mantle. This relationship further suggests that the Proterozoic lithosphere mantle in the southwestern US is probably not a highly degassed reservoir which is contaminated by He derived from the underlying asthenosphere. Instead, 3 He/ 4 He ratios of 5.7 ± 0.3 R A in the most enriched source regions suggest that their (U + Th)/ 3 He is only slightly elevated compared to the depleted upper mantle, and that processes which enrich the lithospheric mantle in large-ion lithophile elements also enrich it in He.
Wild species of Nicotiana as a new source of tobacco resistance to the tobacco hornworm Manduca sexta

Sixteen species of Nicotiana were examined for resistance to second instar larvae of the tobacco horn-worm, Manduca sexta (L.). The tests were designed so as to discriminate between antibiosis and nonpreference. High levels of antibiosis resistance were observed in several wild species such as N. gossei and species in the Repandae section. Several other species, such as N. excelsior, showed antibiosis that appeared to be due to a different mechanism than the alkaloid-trichome exudate based resistance of the above species. The data indicate that these species of Nicotiana may be used as a new source of resistance to larvae of M. sexta. RESUME D'especes sauvages de Nicotiania comme nouvelle source de resistance du tabac a Manduca sexta La resistance aux chenilles de second stade de Manduca sexta L. a ete examinee chez seize especes de Nicotiana. Les essais ont ete concus pour distinguer absence d'appetance et antibiose. Plusieurs especes sauvages comme N. gossei et les especes de la section Repandae ont presente un niveau eleve d'antibiose. D'autres especes, comme N. excelsior ont presente une antibiose vraisemblablement due a un mecanisme different de la resistance des especes precedentes provoquee par un exsudat alcaloide des trichomes. Les resultats indiquent que ces especes de Nicotiana peuvent etre utilisees comme nouvelle source de resistance aux chenilles de M. sexta.
The effect of hyperglycaemia on the rates of appearance and metabolic clearance of glucose in sheep (Ovis aries).

Abstract 1. 1. Glucose appearance and utilization before and during glucose infusions were examined in insulin treated alloxan-diabetic (ITA) and intact sheep. 2. 2. During hyperglycaemia in ITA sheep glucose appearance was reduced to 35% of the preinfusion values whereas in intact sheep it was 17% of preinfusion values. Hyperglycaemia per se appears to inhibit glucose appearance. 3. 3. The utilization of glucose was not proportional to glucose concentrations in ITA sheep, but was in intact sheep where insulin concentrations increased during hyperglycaemia.
On the use of isomer ratios in 44Sc for predicting spin populations in high energy heavy-ion nuclear reactions☆

From fits of isomer ratio as a function of projectile kinetic energy, we have calculated the centroids in the E − J plane for the 44Sc∗ population generated in the reactions 29Si(18O, p2n) 44m, gSc and41K(α, n) 44 m, gSc. It is shown that 44Sc isomer ratios can be used to predict average spins in 44Sc∗, particularly if such ratios are low. As isomer ratios increase, unique identification of average spin populations becomes more difficult because average excitation energy becomes important in determining the isomer ratio.
New rotating target holder for laser ablation and ion beam sputter deposition of multicomponent and multilayered thin films

A versatile ultrahigh vacuum rotating target holder has been designed and constructed for use in ion beam sputter and laser ablation deposition systems for producing multicomponent and/or multilayered thin films. The device features a capability for rotating the targets continuously during exposure to the beams to minimize the development of an undesirable surface topography that otherwise would occur if the targets were still during irradiation. In addition, each individual target holder can be tilted at a predetermined angle. The combined tilting and rotation produces a wobbling movement of the target surface that can be used advantageously to achieve a more uniform distribution of the materials ejected from the targets, which in turn can result in better composition and thickness uniformity of thin films over large area substrates. The device can be baked up to 150 °C depending on the choice of driving motor.
Assessing Demand for Special Education Faculty in Higher Education: A Pilot Study and a Prototype for a National Registry

Supply and demand for special education faculty in institutions of higher education has been an issue of national concern for more than a decade, following efforts to terminate support programs for doctoral study. One organization, the Higher Education Consortium for Special Education (HECSE), and a limited number of investigators have reached reasonable conclusions: there is a critical need to train additional doctoral-level personnel; the existing problem is, in part, a reflection of the greying of the American professoriate, and, a host of other possible factors such as salary, career choice, and instability in American higher education. This study was initiated to accomplish two objectives. First, we tested the feasibility of our approach as the basis for a national study. Knowing that the universe of special education teacher certification programs is small and the universe of programs that train doctoral level personnel is even smaller, it was believed that such a national effort was feasible. Secon...
Bridging the Academic–Public Divide in GIS and Cartography: A Framework for Integrating Community Partnerships in the Classroom

In undergraduate geography programs in the United States there is increasing demand for students to be prepared for real-world project management and to possess strong GIS technical skills and cartographic communication skills upon graduation. There is, however, limited time and opportunity within the framework of traditional undergraduate programs to offer this type of hands-on training while simultaneously increasing conceptual and theoretical knowledge and improving technical abilities. This article outlines a framework for integrating community partnerships into real-world GIS learning opportunities for undergraduate students. Our primary objective is to provide an active learning opportunity that mimics a real-world project scenario within the Geography Department's undergraduate GIS curriculum.
A new unified theory underlying time dependent linear first‐order systems: a prelude to algorithms by design

A new unified theory underlying the theoretical design of linear computational algorithms in the context of time dependent first-order systems is presented. Providing for the first time new perspectives and fresh ideas, and unlike various formulations existing in the literature, the present unified theory involves the following considerations: (i) it leads to new avenues for designing new computational algorithms to foster the notion of algorithms by design and recovering existing algorithms in the literature, (ii) describes a theory for the evolution of time operators via a unified mathematical framework, and (iii) places into context and explains/contrasts future new developments including existing designs and the various relationships among the different classes of algorithms in the literature such as linear multi-step methods, sub-stepping methods, Runge–Kutta type methods, higher-order time accurate methods, etc. Subsequently, it provides design criteria and guidelines for contrasting and evaluating time dependent computational algorithms. The linear computational algorithms in the context of first-order systems are classified as distinctly pertaining to Type 1, Type 2, and Type 3 classifications of time discretized operators. Such a distinct classification, provides for the first time, new avenues for designing new computational algorithms not existing in the literature and recovering existing algorithms of arbitrary order of time accuracy including an overall assessment of their stability and other algorithmic attributes. Consequently, it enables the evaluation and provides the relationships of computational algorithms for time dependent problems via a standardized measure based on computational effort and memory usage in terms of the resulting number of equation systems and the corresponding number of system solves. A generalized stability and accuracy limitation barrier theorem underlies the generic designs of computational algorithms with arbitrary order of accuracy and establishes guidelines which cannot be circumvented. In summary, unlike the traditional approaches and classical school of thought customarily employed in the theoretical development of computational algorithms, the unified theory underlying time dependent first-order systems serves as a viable avenue to foster the notion of algorithms by design. Copyright © 2004 John Wiley & Sons, Ltd.
Factors Influencing Student Prerequisite Preparation for and Subsequent Performance in College Chemistry Two:: A Statistical Investigation

For students entering Chemistry Two following a Chemistry One course, an assessment exam was given and the results were evaluated in combination with other variables to develop a predictive model that forecasts student achievement in the course. Variables considered in the analysis included student major, GPA, classification (student standing: first year, second year, etc.), Chem One grade, delay since Chem One was completed, institution type at which Chem One was completed, Chem One instructor, enrollment status in the Chem Two lab, number of repeats of Chem Two, and semester of enrollment. Our results suggest that 27−28% of variability in semester course grades can be explained on the basis of the combined influence of only six variables. We identify four general factors that we believe should be considered simultaneously in the assessment of potential student strengths and weaknesses early in the Chem Two semester: historical academic achievement, quality of prerequisite preparation, academic background, and student motivations and attitudes. By implementing a chemistry background assessment and evaluating the results in combination with relevant demographic data, instructors can be better equipped to identify students at risk—both academically and motivationally—and to address those needs and improve student success.
Repeatability of physiological responses during two repeated protective clothing performance tests under identical test conditions

Abstract Physiological variables were measured in subjects (n = 10) during exercise (50% V ˙ O2max) on two separate occasions while wearing protective clothing under identical controlled conditions (22 °C, 50% relative humidity). We hypothesized that there would be no significant difference in measured physiological variables between two separate trials. Rectal temperature and heart rate responses were not statistically different between trials and within subjects (p = 0.270; p = 0.85, respectively) whereas mean skin temperature (p = 0.049) and sweat rate ([kg•h−1]; 1.31 ± 0.52 vs. 1.17 ± 0.38; p = 0.438) showed a greater variability between trials. We concluded that in general, that heart rate and rectal temperature responses during exercise testing while wearing protective clothing are less variable and more repeatable than sweat rate and skin temperature responses. Relevance to Industry Comparison of the physiological “burden” of different protective ensembles may aid industry in the proper selection and use of the ensemble that balances both the protective nature against hazards with the least physiological burden to the wearer. Repeatable testing increases the reliability of the selection of the appropriate ensemble.
Isolation and primary structure of the major toxin from sea snake, Acalyptophis peronii, venom

The major neurotoxin from the venom of Acalyptophis peronii captured in the Gulf of Thailand was isolated. Although there are two toxic fractions in the venom, the most toxic and abundant fraction was selected for purification and chemical characterization. The LD50 of the major toxin is 0.125 micrograms/g mice, indicating an extremely toxic nature. The toxin consists of 60 amino acid residues with methionine as the amino-terminal and asparagine as the carboxy-terminal end. It contains nine half-cystine residues. There is 1 mol each of tryptophan, tyrosine, methionine, valine, aspartic acid, leucine, and alanine, and there is no phenylalanine. The molecular weight calculated from the amino acid sequence determination was 6600. The toxin replaces alpha-bungarotoxin in binding with the acetylcholine receptor, indicating that the A. peronii major neurotoxin competes with alpha-bungarotoxin for the same binding site of the acetylcholine receptor.
Sinuosity of Alluvial Rivers on the Great Plains

Data on the morphologic and sediment characteristics of stable alluvial rivers of the Great Plains were collected at 50 cross sections. The channel patterns of these rivers were classified into five types: tortuous, irregular, regular, transitional, and straight. Because no clear demarcation existed between each of the types, the pattern of the rivers was described by sinuosity, a ratio of channel length to valley length. The sinuosity ( (P) ) of these rivers is related to the shape of the channels expressed as a width-depth ratio ( F ) and to the percentage of silt and clay in the perimeter of the channel ( M ) as follows: ![Formula][1] ![Formula][2] Sinuous streams are characterized by a low width-depth ratio ( F ), a high percentage of silt-clay in the perimeter of the channel ( M ), a high percentage of silt-clay in the banks (although the banks of straight channels may also contain large amounts of silt-clay), and a lower gradient than straight channels having the same mean discharge. Discharge itself does not appear to affect the sinuosity of streams. Another possible distinction between straight and sinuous streams is in the proportions of the components of total sediment load. In a wide, shallow channel much of the sediment transported is bed-material load. In a narrow, deep channel most of the sediment transported is wash load. On the Great Plains both straight and sinuous streams may flow on the surface of alluvial valley fills at about the same valley slope. The departure of a stream from a straight course down the alluvial valley results from changes in both the caliber of the sediment load and in the relative proportions of bed-material load and wash load during the post-Pleistocene alluviation of these valleys. When during this alluviation the proportion of wash load increased, most probably by a decrease in bed-material load, the stream adjusted itself by decreasing its gradient through the development of a sinuous course. Recent changes in stream sinuosity in response to changes in the proportions of bed load and suspended load support this hypothesis. [1]: /embed/graphic-1.gif [2]: /embed/graphic-2.gif
Ontogeny of retinal oil droplets in the chick embryo.

The origin of the colored oil droplets in the chick cones was investigated by subjecting retinas from staged embryos to correlative biochemical (visible spectrophotometric assays of chromatographically separated extracts) and microscopic analyses. The carotenoid pigments responsible for the coloration of the oil droplets are detected spectrophotometrically before they can be visualized microscopically in the form of colored droplets. The spectrophotometric data reveal that each pigment arises independently in the following sequence: golden yellow, yellowish green, and red. The golden yellow hydrocarbon is first detected at stage 27 at which time the retina consists of a thick, unstratified, neuroepithelial layer with an active proliferative zone, but lacks visual cells. Galloxanthin, the yellowish green pigment, arises at stage 34. The retina is still devoid of visual elements at this stage but is organized into several nuclear layers. The concentrations of the golden yellow and yellowish green carotenoids begin to increase rapidly at stage 37 when inner segments are differentiating, but oil droplet vacuoles have not yet appeared within them. Colorless droplets first evident in fresh preparations of this stage may not be colorless at all, but may contain the yellow pigments in sach low concentrations that their colors cannot be discriminated microscopically. The red pigment, astaxanthin, is first evident at stage 41 and immediately exhibits a steady increase in concentration. The retina possesses adult stratification at this time; all ten layers are present and oil droplet vacuoles are observed for the first time. On the basis of the spectrophotometric findings it is contended that the double cones are the first cones to differentiate in the chick retina and that the chief component (bearer of the golden yellow droplet) arises before the accessory element (carrier of the yellowish green droplet).
Mice Lacking the Guanylyl Cyclase C Receptor Are Resistant to STa-Induced Intestinal Secretion

Heat-stable enterotoxin (STa) is an important causative agent of diarrheal disease throughout the world. STa is known to bind specifically to receptors in the intestine, provoking intense intestinal secretion. Binding of STa, or of the mammalian endogenous ligands guanylin and uroguanylin, activates the guanylyl cyclase C receptor (GC-C); the resulting elevation of cGMP levels stimulates chloride secretion via CFTR. We have generated knockout mice which completely lack the GC-C receptor. These mice are viable and show no obvious alteration in intestinal fluidity. However, GC-C null mice are refractory to the secretory action of STa, proving that the GC-C receptor is necessary for the diarrheal response induced by STa.
A Comparison of Various Methods of Demonstrating Influenza Virus in Throat Washings.

SummaryDuring the epidemic of influenza A in 1943-44, throat washings from military personnel were tested in ferrets or hamsters, or in both species, and a smaller number of the same washings were inoculated into chick embryos.None of the throat washings from 23 persons in whom response to serological tests for influenza A virus was negative produced antibodies to that virus after intranasal inoculation in ferrets.Of 30 throat washings from persons showing positive response to serological tests for influenza A virus, 17 (56.7 ± 9.05%) produced in ferrets an increase in antibodies to the virus. With 2 exceptions all ferrets showing an increase in antibodies also developed fever 2 to 3 days after inoculation. Four of 41 ferrets showing no increase in antibodies had similar febrile reaction.Thirty, or 56.6 ± 6.81% of 53 throat washings from persons with known cases of influenza A were positive in hamsters, a result identical with that obtained in ferrets. Twelve throat washings that were negative in ferrets ...
Preparing Elementary Preservice Teachers for Urban Elementary Science Classrooms: Challenging Cultural Biases toward Diverse Students.

This study reports the learning of elementary preservice teachers regarding diversity and teaching science in diverse urban elementary classrooms. From participating in a semester-long book club, the preservice teachers reveal their cultural biases, connect and apply their knowledge of diversity, and understand that getting to know their students are important elements for teaching science in diverse classrooms. These 3 things connect in ways that allow the preservice teachers to understand how their cultural biases impede student learning and gain new knowledge of diversity as they change their cultural biases. Implications of this study reveal that preservice teachers need opportunities to reveal, confront, challenge, and change their cultural models and to develop new models for teaching science in urban elementary classrooms.
Major liver resection for non-Hodgkin's lymphoma in an HIV-positive patient: report of a case.

A very unusual clinical presentation of non-Hodgkin's lymphoma (NHL) of the liver is reported herein. The patient was a 35-year-old male who had been HIV-positive since 1987. Following an episode of acute pain in the right upper abdominal quadrant, ultrasonography (US) and computed tomography (CT) were performed, revealing a nodular tomography (CT) were performed, revealing a nodular lesion, 2.5 cm in diameter, localized in the eight segment of the liver. Despite the fact that the lesion became significantly enlarged over a 6-month period, three repeated percutaneous biopsies proved negative. Finally, his increasing pain and the lack of a definitive diagnosis prompted us to perform a right hepatectomy. The patient had an uneventful postoperative course and is well 1 year after his operation. Establishing a diagnosis of extranodal lymphoma can be difficult, especially in HIV-positive or AIDS patients. Thus, performing a laparotomy is justified to confirm a diagnosis and decide upon the most appropriate treatment. However, in about 10% of these patients, only surgical resection allows for the diagnosis. In accordance with other reports, our experience confirms that, in contrast with AIDS patients, HIV-positive patients have a similar prognosis as non-HIV patients, and are suitable candidates for even major surgical procedures.
An unusual genotype in an Ashkenazi Jewish patient with Tay-Sachs disease

The Ashkenazi Jewish population is enriched for carriers of a fatal form of Tay-Sachs disease, a recessive inherited disorder caused by mutations in the alpha-chain of the lysosomal enzyme beta-hexosaminidase A. Approximately 20% of the Ashkenazi carriers harbor a splice junction defect while about 78% bear a 4 base pair (bp) insertion. However, the Ashkenazi Jewish patient used in the original description of the 4 bp insertion carried this lesion in only 1 allele and was negative for the splice junction mutation. We cloned the insertion negative allele and by sequence analysis of the exons found a point mutation in exon 11 that results in substitution of Trp392 with a premature termination codon. Nine Ashkenazi Jewish carriers that tested negative for the major and minor mutations as well as for a lesion causing an adult form of Tay-Sachs disease did not carry the base change defect, suggesting that it may be a recent and/or rare mutation. This finding also indicates that screening the Ashkenazi population solely by recombinant DNA methods for the splice junction, 4 bp insertion, and adult mutations may result in occasional false negatives.
Upregulation of Na+/Ca2+ exchanger contributes to the enhanced Ca2+ entry in pulmonary artery smooth muscle cells from patients with idiopathic pulmonary arterial hypertension.

A rise in cytosolic Ca2+ concentration ([Ca2+]cyt) in pulmonary artery smooth muscle cells (PASMC) is a trigger for pulmonary vasoconstriction and a stimulus for PASMC proliferation and migration. ...