cssi/SciSciGPT-SciSciNet huggingface dataset:
Smoothing lung segmentation surfaces in 3D x-ray CT images using anatomic guidance

Several methods for automatic lung segmentation in volumetric computed tomography (CT) images have been proposed. Most methods distinguish the lung parenchyma from the surrounding anatomy based on the difference in CT attenuation values. This can lead to an irregular and inconsistent lung boundary for the regions near the mediastinum. This paper presents a fully automatic method for the 3D smoothing of the lung boundary using information from the segmented human airway tree. First, using the segmented airway tree we define a bounding box around the mediastinum for each lung, within which all operations are performed. We then define all generations of the airway tree distal to the right and left mainstem bronchi to be part of the respective lungs, and exclude all other segments. Finally, we perform a fast morphological closing with an ellipsoidal kernel to smooth the surface of the lung. This method has been tested by processing the segmented lungs from eight normal datasets. The mean value of the magnitude of curvature of the contours of mediastinal transverse slices, averaged over all the datasets, is 0.0450 before smoothing and 0.0167 post smoothing. The accuracy of the lung contours after smoothing is assessed by comparing the automatic results to manually traced smooth lung borders by a human analyst. Averaged over all volumes, the root mean square difference between human and computer borders is 0.8691 mm after smoothing, compared to 1.3012 mm before. The mean similarity index, which is an area overlap measure based on the kappa statistic, is 0.9958 (SD 0.0032).
Assessing the rural development potential of lignocellulosic biofuels in Alabama.

Abstract We examine the potential rural development impacts of a highly decentralized system of feedstock production, biorefining, and consumption of locally-produced lignocellulosic biofuels in Alabama, a heavily forested state in the southeastern United States. Primary data based on in-depth interviews and public presentations by experts were used to establish a realistic scenario for development of a lignocellulosic biofuels industry in Alabama. Based on these data, we applied an input–output model to illustrate economic impacts of establishing six biorefineries, each with an annual capacity of 189 dam3. We applied this same model to analyze the impact of one biorefinery of that size on a set of rural counties in west Alabama, a region characterized both by abundant timber resources and persistent rural poverty. Research findings reveal a high potential for economic development and job growth, especially in the logging sector and in rural regions of the state. The trajectory of this development and distribution of benefits from this incipient industry will depend on federal, state and local policies. We identify types of policies that would simultaneously encourage growth of this industry and ensure that those who live in areas where production and refining operations take place benefit from this development.
Projection operator method in two-level atoms

Abstract The projection operator method is used to study time-correlation functions in the theory of two-level atoms.
Combining multi‐observer information in partially rank‐ordered judgment post‐stratified and ranked set samples

This paper develops two sampling designs to create artificially stratified samples. These designs use a small set of experimental units to determine their relative ranks without measurement. In each set, the units are ranked by all available observers (rankers), with ties whenever the units cannot be ranked with high confidence. The rankings from all the observers are then combined in a meaningful way to create a single weight measure. This weight measure is used to create judgment strata in both designs. The first design constructs the strata through judgment post-stratification after the data has been collected. The second design creates the strata before any measurements are made on the experimental units. The paper constructs estimators and confidence intervals, and develops testing procedures for the mean and median of the underlying distribution based on these sampling designs. We show that the proposed sampling designs provide a substantial improvement over their competitor designs in the literature. The Canadian Journal of Statistics 41: 304–324; 2013 © 2013 Statistical Society of Canada Dans cet article, nous developpons deux plans d'echantillonnage pour creer des echantillons stratifies artificiellement. Ces plans utilisent un petit ensemble d'unites experimentales pour determiner leurs rangs relatifs sans les mesurer. Dans chaque ensemble, les unites sont classees en fonction de tous les observateurs disponibles (classeurs), tout en permettant des egalites lorsque le rang des unites ne peut etre etabli a un niveau de confiance eleve. Les classements de tous les observateurs sont ensuite combines de facon judicieuse en une mesure de poids unique utilisee pour creer une stratification de jugement dans les deux plans. Le premier plan construit les strates par le biais de jugement post-stratification, apres la collecte des donnees. Le deuxieme plan cree les strates avant la prise de toute mesure sur les unites experimentales. Nous presentons des estimateurs et des intervalles de confiance, ainsi que des procedures de test pour la moyenne et la mediane de la distribution sous-jacente basees sur ces plans d'echantillonnage. Nous montrons que les plans d'echantillonnage proposes constituent une amelioration considerable par rapport aux plans concurrents dans la litterature. La revue canadienne de statistique 41: 304–324; 2013 © 2013 Societe statistique du Canada
End-to-end accountability in grid computing systems for coalition information sharing

Accountability is crucial for any computer system. It assures that every action executed in the system can be traced back to some entity. Accountability for grid computing systems is even more crucial given the very large number of users and active entities in these systems. However, so far no comprehensive approach to accountability for grid systems exists. Our work addresses such lack by developing a comprehensive accountability system driven by policies and supported by accountability agents. This paper first discusses the requirements that have driven the design of our accountability system. It then presents the key elements of our approach, namely the accountability data, the accountability policy language, and the agents.
A spectral-like turbulence-resolving scheme for fine sediment transport in the bottom boundary layer

A hybrid spectral-compact finite difference scheme for turbulent-resolving simulation of fine sediment transport in the bottom boundary layer is presented. The numerical approach extends an earlier pseudo-spectral model for direct numerical simulation (DNS) of turbulent flows with a sixth-order compact finite difference scheme in the wall-normal direction on Chebyshev grid points. The compact finite difference scheme allows easy implementation of flow-dependent properties (e.g., viscosity, diffusivity and settling velocity) and more flexible boundary conditions while still maintain spectral-like numerical accuracy. The numerical model is verified with analytical solutions of flow velocity and particle concentration of two simple Newtonian rheological closures under laminar condition. Prior laboratory and DNS data of turbulent channel flow are also used to validate the code. Several numerical simulations were carried out in a turbulent channel flow setting to investigate the interplay between the two turbulence modulation mechanisms induced by the presence of sediment, namely sediment-induced density stratification and enhanced viscosity due to rheological stress. We demonstrate that at the Reynolds number, Richardson number, and non-dimensional settling velocity used here, the flow remains turbulent but sediment-induced density stratification already causes noticeable damping of turbulence (drag reduction). By further introducing a Newtonian rheological stress into the system, flow turbulence is further damped by the increased effective viscosity, which can trigger laminarization. HighlightsA hybrid spectral-compact finite difference turbulence-resolving scheme is developed.We investigate the turbulence modulation mechanisms induced by the presence of sediment.By introducing simply a Newtonian rheological model, flow turbulence is further damped by the increased effective viscosity.For fine sediment, a rheological effect can trigger flow laminarization even the bulk Richardson number is below critical value.
Neuroscience: Channelopathies have many faces.

A sodium channel known for its role in the perception of pain also seems to be necessary for olfaction. The multiple roles of this channel and the diverse effects of its mutations raise intriguing questions. See Article p.186 Humans and mice with mutations in the gene coding for the voltage-gated sodium ion channel Nav1.7, previously shown to be insensitive to pain, are now found to be unable to perceive odours. Olfactory sensory neurons that are missing this sodium channel still produce action potentials, but their synapses fail to transmit to downstream neuronal circuits. The Nav1.7-deficient phenotype of mice resembles that of human patients with Nav1.7 loss-of-function mutations, indicating that elimination of this ion channel creates a mouse model of congenital general anosmia.
Pharmacologic profile of lipoxins A5 and B5: new biologically active eicosanoids.

In this study, we have investigated the biological activities of LxA5 and LxB5 in isolated smooth muscle preparations of the guinea pig. LxA5 slowly contracted pulmonary parenchymal strips isolated from guinea pigs in a concentration-dependent manner over the range of 0.1-2.2 microM. This bronchoconstrictor effect was not associated with release of peptide leukotrienes (i.e. LTC4, LTD4 and LTE4) and only a slight increase in thromboxane B2. Furthermore, the bronchoconstrictor effect was not blocked by lipoxygenase inhibitors, suggesting the pulmonary effect is not mediated by lipoxygenase products. However, a peptide leukotriene receptor antagonist (e.g. SK&F-104353) inhibited or reversed the LxA5 response indicating that LxA5 and the peptide leukotrienes may share the same receptor. In contrast to LxA5, LxB5 displayed no significant bronchoconstrictor effect at concentrations up to 2.2 microM. Moreover, LxA5 and LxB5 did not exert a significant endothelium-dependent vasorelaxation in aortic vascular smooth muscle as do LxA4 and LxB4. Thus, LxA5 and LxB5 display a unique biological profile which differs from LxA4 and LxB4. LxA4 may be a mediator in circulatory disease states (e.g. myocardial ischemia, circulatory shock), but LxA5 and LxB5 are not as likely candidates as mediators of disease.
Genotype interaction with undernutrition and external environment in early life.

IN spite of the well documented effect of early undernutrition on body and brain size in adult animals1–3, its reported influence on behaviour has been less consistent. Changes in performance in learning tasks and activity tests have been found following undernutrition in early life4–7. Several studies, however, have shown little or no effect of such a manipulation8–10. Here we consider two factors which may contribute to variability in later behavioural response to early life undernutrition.
Trophic factors: An evolutionary cul-de-sac or door into higher neuronal function?

Trophic factors, such as the neurotrophins, CNTF, and GDNF, represent unique families of proteins that are essential for the development of the vertebrate nervous system. Surprisingly, there is little evidence to date that these proteins exist in Drosophila melanogaster and Caenorhabditis elegans, even though other polypeptide growth factors, such as EGF, FGF, and insulin, are conserved in these species. For the neurotrophins, the evolution of NGF, BDNF, NT-3, and NT-4 as a family implies that these signaling molecules may be involved in mediating additional neural activities, such as learning, memory, and behavior. Indeed, there is abundant evidence now that BDNF is involved in synapse modification, neurotransmitter release, long-term potentiation, and mechanosensation. The widening scope of neurotrophin action will require more physiological, genomic, and integrative approaches to understand fully the mechanisms by which survival factors can mediate so many diverse effects.
Serum LH Levels in Intact and Castrated Golden Hamsters

The concentrations of LH in serum have been measured by radioimmunoassay in golden hamsters maintained in an environment with controlled lighting (on at 5 AM; off at 7 PM, CST). The maximal concentration of LH in serum of cycling hamsters occurred between 3 and 4 PM on the proestrous day, at which time the LH concentration increased as much as 50- to 100-fold within a short time. The pattern of LH release in the cycling hamster is very similar to that in the rat. Ovulation occurs 9–10 hr after the LH surge. In contrast to intact female hamsters during diestrus in which the concentration of LH in serum is quite low, female hamsters ovariectomized during diestrus have markedly increased serum LH levels within 3.5 hr following removal of the ovaries. Intact males showed great variability in serum LH levels, and the average LH concentration in intact male hamsters was much higher than that observed in diestrous females. Serum LH concentrations in males were noticeably elevated 24 hr after removal of the teste...
Thermally induced He II vaporization threshold for superconducting and normal lead

Abstract The limiting heat current density at which vaporization is initiated in He II at a lead surface is shown to be a function of the liquid temperature without significant effects of the state of order in the solid.
Temporal context calibrates interval timing.

The authors find that a person's estimate of a time interval exhibits biases that depend on both its duration and the distribution from which it is drawn. This behavioral pattern could be described using a Bayesian model. These findings suggest that internal timing mechanisms can adapt to the temporal statistics of the environment to minimize uncertainty. We use our sense of time to identify temporal relationships between events and to anticipate actions. The degree to which we can exploit temporal contingencies depends on the variability of our measurements of time. We asked humans to reproduce time intervals drawn from different underlying distributions. As expected, production times were more variable for longer intervals. However, production times exhibited a systematic regression toward the mean. Consequently, estimates for a sample interval differed depending on the distribution from which it was drawn. A performance-optimizing Bayesian model that takes the underlying distribution of samples into account provided an accurate description of subjects' performance, variability and bias. This finding suggests that the CNS incorporates knowledge about temporal uncertainty to adapt internal timing mechanisms to the temporal statistics of the environment.
Changes in physical and chemical properties of soil after surface mining and reclamation

Abstract Mining causes drastic disturbances in landscape and soil properties, and reclamation can restore soil quality over time. Thus, assessing changes in properties of reclaimed mine soils is essential to understanding the effects of the reclamation techniques. This study was aimed at quantifying the effects of mining and reclamation processes on physical and chemical properties of reclaimed soils for three dominant soil series in Ohio: Mahoning–Canfield–Rittman–Chili, Coshocton–Westmoreland–Berks, and Gilpin–Upshur–Lowell–Guernsey. Three newly reclaimed mine sites ( 200% higher than those for the undisturbed sites (43 to 154 μS cm− 1). In the 0–15 cm depth, SOC pools in RMSs (1.2 to 2.5 Mg ha− 1) declined by 52 to 83% of undisturbed sites (11 to 29 Mg ha− 1). Similarly, N pools in RMSs (1.2 to 2.5 Mg ha− 1) declined by 42 to 75% of undisturbed sites (3.1 to 5.1 Mg ha− 1). Clay content was positively correlated with SOC concentration in the RMSs but not in the undisturbed site. This trend indicates that a RMS high in clay content has a relatively high SOC sink capacity. The SOC, N, C:N ratio, and EC in the subsurface layer of RMSs were similar to those of the surface soil, although later received a topsoil cover. Such a trend suggests that topsoil materials require better handling during removal, storage, and application so as to preserve soil structure, nutrients, SOC, and N pools.
Treatment of Streptococcal Pharyngitis with Amoxicillin

Amoxicillin and penicillin V were used to treat pharyngeal infections due to group A 0-hemolytic Streptococcus in children. Patients were assigned randomly to receive either antibiotic, both of which were administered in a dose of 125 mg three times a day for 10 days. Cultures were obtained from all patients before and three and five weeks after therapy. Cultures were T typed to distinguish recurrences from new infections. There were no differences in the two groups with respect to age, weight, physical findings, or laboratory data. Cure rates were 80.8 % for penicillin V and 76.6% for amoxicillin. These results were comparable to results of other therapeutic regimens. Approximately half the failures in each group were clinical recurrences. Amoxicillin was well tolerated, and fewer gastrointestinal side effects were seen with amoxicillin than with penicillin V. Five children treated with amoxicillin developed rashes similar to those seen with ampicillin. Amoxicillin was as effective as penicillin V in the treatment of pharyngitis due to group A Streptococcus. Amoxicillin (a-amino-p-hydroxybenzylpenicillin) is a new semisynthetic penicillin with a chemical structure and spectrum of antibacterial activity
A Useful Preparation of L- (S) -Glyceraldehyde Acetonide

Abstract In our current synthetic work directed toward spiroketal containing natural products, we needed to have access to (S)-glyceraldehyde acetonide in pure form. While Baer and Fischer described a preparation of this material in 1939 by a route analogous to that developed for (R)-glyceraldehyde acetonide, the use of unnatural L-mannitol is required.' More recently, Jung and Shaw have developed an expedient synthesis of (R)- glycerol acetonide from ascorbic acid which passes through (s)-g1yceraldehyde acetonide.2 This unstable aldehyde was not isolated, but was reduced directly to the alcohol. Additionally, Takano c.e.have reported a modification of the ascorbic acid route, but this procedure also proceeds directly to the alcoh0l.3 Since attempts in our hands to modify the JUng procedure so as to procure the aldehyde itself led to poor yields of impure material, we were forced to develop an alternate route.
Preferences for Careers in Public Work: Examining the Government-Nonprofit Divide Among Undergraduates Through Public Service Motivation

Public service motivation (PSM) research has demonstrated the association of PSM with interest in government and nonprofit careers. Perry’s PSM instrument also sheds light upon a less studied aspect of career interest among college students—the perception that the nonprofit sector, and not government, provides the better outlet for altruistic values. The author argues that given the lack of confidence in government and negative perceptions toward government work, only the attraction to policy making dimension predicts interest in government careers. In contrast, commitment to public interest, compassion, and self-sacrifice should explain student interest in nonprofits as well as teaching—both fields of work students see as more directly helping and serving people. Analyses of data from an Internet-based survey of 529 upper-division students at two upper-Midwest universities confirm this “divide” between the rational and normative/affective dimensions of PSM and suggest that confidence in institutions shou...
Acute ischemic syndromes following coronary artery bypass graft surgery

Coronary artery bypass graft (CABG) surgery, performed for the control of angina pectoris, leads to postoperative relief from symptoms in most patients. Amelioration of ischemia and improvement in exercise capacity after CABG are well documented. However, patients currently undergoing CABG are more complex than in the past--they are older and are maintained on medical therapy for longer periods. A large number of these patients have had one or more previous myocardial revascularization procedures. The post-operative period would appear to be a time of vulnerability for coronary events. However, previous investigators have focused on the pre- and intraoperative aspects of peri-CABG ischemia. Outcome data suggest that the postoperative interval is at least equally important as a determinant of short- and long-term morbidity and mortality. We discuss the epidemiology, etiology, pathophysiology, and treatment of ischemic syndromes in the postoperative period after CABG. In addition, we review recent data from a series of 14 patients, observed at our institution, who underwent cardiac catheterization and, in some cases, angioplasty of the culprit vessel in the immediate postoperative period.
Combined CYP2C9, VKORC1 and CYP4F2 frequencies among racial and ethnic groups

Aims: CYP4F2*3 (p.V433M) has been associated with higher warfarin dose requirements; however, its frequency, like other CYP2C9 and VKORC1 variants, has not been systematically assessed in major racial/ethnic populations. Thus, we determined the individual and combined frequencies of important CYP2C9, VKORC1 and CYP4F2 variants in several racial/ethnic groups. Materials & methods: Healthy African–American, Asian, Caucasian, Hispanic and Ashkenazi Jewish (AJ) blood donors were genotyped for CYP2C9 (*2, *3, *4, *5, *6, *8, *11 and *13), VKORC1 (g.-1639G>A) and CYP4F2 (*3 [p.V433M] and rs2189784). Results: The combined frequencies of variant CYP2C9 alleles were 0.133, 0.078, 0.212, 0.178 and 0.212 among African–American, Asian, Caucasian, Hispanic and AJ individuals, respectively. CYP4F2*3 frequencies were prevalent (0.233–0.342) among Asian, Caucasian, Hispanic and AJ individuals, while significantly less frequent among African–Americans (0.117; p < 0.0001). In addition, CYP4F2*3 was in linkage disequilibriu...
Interstitial trypsinogen release and its relevance to the transformation of mild into necrotizing pancreatitis in rats.

Abstract Background & Aims: Intracellular activation of trypsinogen is currently believed to initiate pancreatitis. Factors responsible for the progression of mild to necrotizing pancreatitis are poorly understood. This study evaluated the significance of interstitial protease release and activation in this process. Methods: In rats with cerulein-induced pancreatitis, concentrations of trypsinogen and its activation peptide TAP were measured in lymph and blood, and pancreatic injury was determined. Activation of extracellular trypsinogen was induced by intravenous infusion of enterokinase, which does not enter the acinar cell. Gabexate mesilate (acinar cell permeable) or soybean trypsin inhibitor (acinar cell nonpermeable) was administered to distinguish the effects of intracellular or extracellular protease activation. Results: In cerulein pancreatitis, trypsinogen levels increased prominently and were highest in lymph and portal vein blood, whereas TAP increments were modest. Combined cerulein/enterokinase infusions resulted in marked TAP increases in lymph and blood and in severe necrohemorrhagic pancreatitis. Gabexate mesilate as well as soybean trypsin inhibitor significantly decreased TAP levels in both lymph and blood and reduced pancreatic injury, with no significant differences between groups. Conclusions: In secretagogue-induced pancreatitis, large amounts of trypsinogen are present in the interstitium and drain via the portal and lymphatic circulation. Activation of this extracellular trypsinogen induces hemorrhagic necrosis in a setting of mild edematous pancreatitis. This phenomenon may be the central event in the progression to fulminant necrotizing pancreatitis. GASTROENTEROLOGY 1999;117:717-725
Inhibition of the Discoloration of Polyurethane Foam Caused by Ultraviolet Light

The discoloration of polyurethane foam by UV light can result in a product that is less aesthetically pleasing and can give the impression that the product has physically degraded. Discoloration prior to wrapping and/or fabrication can result in rejected orders or increased scrap from trimming away discolored surfaces, Work at ARCO Chemical has demonstrated that phosphite additives to flexible polyurethane foam will delay UV discoloration and provide more of a time window for handling and fabrication. Benefits are seen in both fire retarded and non-fire retarded foams. In this article, data is presented which quantifies the amount of delay versus the level and type of phosphite used. Several different foam grades and various formulation variables are included in the studies
A block varaint of the GMRES method for unsymmetric linear systems

Iterative methods that take advantage of efficient block operations and block communications are popular research topics in parallel computation. These methods are especially important on Massively Parallel Processors (MPP). This paper presents a block variant of the GMRES method for solving general unsymmetric linear systems. It is shown that the new algorithm with block sizes, denoted by BVGMRES (s.m), is theoretically equivalent to the GMRES (s·m) method. The numerical results show that this algorithm can be more efficient than the standard GMRES method on a cache besed single CPU computer with optimized BLAS kernels. Furthermore, the gain in efficiency is more significant on MPPs due to both efficient block operations and efficient block data communications. Our numerical results also show that in comparison to the standard GMRES method, the more PEs that are used on an MPP, the more efficient the BVGMRES(s,m) algorithm is.
Antigenic variation among polyoma viruses from different sources demonstrated by plaque neutralization.

The antigenic relationship between strains of polyoma virus isolated in three independent laboratories was studied by a plaque neutralization technique. The large-plaque strains showed the greatest cross-reactivity. In contrast, small-plaque strains differed significantly from the large-plaque strains derived from the same virus isolates. In addition, each small-plaque strain differed significantly from each other. The antigenic characteristic was stable on plaque purification, terminal dilution selection, or passage in hamster embryo cell cultures.
Equianalgesic dosing: implications for the perianesthesia setting.

AN UNDERSTANDING of how to administer opioid analgesics becomes very important as institutions embark on initiatives that emphasize pain assessment and management. Equianalgesic dosing tables have existed for years; yet suddenly, these tables are appearing on pocket cards, Web sites, and staff education materials. Knowledge of the equianalgesic table allows the perianesthesia health care provider to effectively use all of the opioids, regardless of the route of administration (parenteral or oral). By calculating an equianalgesic dose, one can determine the dose and route of administration of opioids that will provide approximately the same amount of pain relief. At equianalgesic doses, opioids should be interchangeable.
Social Networks and Social Movements: Multiorganizational Fields and Recruitment to Mississippi Freedom Summer

This study explores the role of multiorganizational fields in recruitment to social movements. We study applicants to the 1964 Mississippi Freedom Summer project from two sites: the University of California at Berkeley and the University of Wisconsin at Madison. Using network analysis, we develop a model of recruitment that predicts participation on the basis of the structural positions of individuals within the multiorganizational fields, as well as on the basis of individual background factors. We also study the role that the recruitment context plays, by comparing the results at these two universities. Independent of the individual background factors, structural position in the multiorganizational field predicts participation in Freedom Summer at Wisconsin, but not at Berkeley. The effects of individual background factors on participation are also contingent on the recruitment context. We discuss the theoretical implications of our results for the study of the effects of multiorganizational fields and recruitment contexts on participation in social movements.
Internal solitons on the pycnocline: generation, propagation, and shoaling and breaking over a slope

In Part 1 a study is made of the internal solitary wave on the pycnocline of a continuously stratified fluid. A Korteweg–de Vries (KdV) equation for the ‘interfacial’ displacement is developed following Benney's method for long nonlinear waves. Experiments were conducted in a long wave tank with the pycnocline at several different depths below the free surface, while keeping the total depth approximately constant. A step-like pool of light water, trapped behind a sliding gate, served as the initial disturbance condition. The number of solitons generated was verified to satisfy the prediction of inverse-scattering theory. The fully developed soliton was found to satisfy the KdV theory for all ratios of upper-layer thickness to total depth.In Part 2 of this study we investigate experimentally the evolution and breaking of an internal solitary wave as it shoals on a sloping bottom connecting the deeper region where the waves were generated to a shallower shelf region. It is found through quantitative measurements that the onset of wave-breaking was governed by shear instability, which was initiated when the local gradient Richardson number became less than ¼. The internal solitary wave of depression was found to steepen at the back of the wave before breaking, in contrast with waves of elevation. Two slopes were used, with ratios 1:16 and 1:9, and the fluid was a Boussinesq fluid with weak stratification using brine solutions.
Changing Food Preference as a Function of Mood

The authors investigated the effect of mood on food selection. Participants (N = 98) indicated the likelihood of general eating and the likelihood of eating specific foods after reading and projecting themselves onto the events and emotions described in a sad and a happy vignette. Both men and women believed they were more likely to consume food following a happy versus a sad event, and men believed they were significantly more likely to eat than did women. However, the type of food men and women believed they would consume interacted with the type of event experienced. Vegetarian snack foods were more likely to be consumed following a happy versus a sad event, with men more likely to eat snack foods. Men did not significantly change in likelihood of consuming sweet foods as their mood changed. However, women believed they were more likely to consume sweet foods following a sad event. The authors discuss the results in terms of a self-medication hypothesis and the effect of carbohydrates on central seroto...
Knowledge based identification of fractionally sampled channels

Blind channel identification has been a popular research subject in recent years. We introduce the concept of knowledge-based blind channel identification. By relying on known information such as the pulse shaping filter and the antialiasing filter responses, the performance of channel identification and equalization can be significantly enhanced in digital communication systems. We present two simple methods: one in time-domain and one in frequency domain. Our simulation results demonstrate the performance of these two approaches.
Sources of Variance in Temporal and Spatial Aspects of Jaw Kinematics in Two Species of Primates Feeding on Foods of Different Properties

Synopsis Chewing kinematics reflects interactions between centrally generated motor signals and peripheral sensory feedback from the constantly changing oral environment. Chewing is a strongly modulated behavior that responds to differences in material properties among different type of foods and to changes in the external physical properties of the food as the bolus gets processed. Feeding, as any complex biological behavior, presents variation at multiple hierarchical levels, from among species or higher-order levels to variation among chewing cycles within a single feeding sequence. Thus, to understand the mechanics and evolution of feeding systems requires estimation of how this variation is distributed across each of these hierarchical levels, which in turn requires large sample sizes. The development of affordable, high-resolution, three-dimensional kinematic recording systems has increased our ability to collect large amounts of data on complete or near-complete feeding sequences that can be used to shed light on the mechanisms of control in vertebrate feeding. In this study, we present data on the nature and sources of variation (from species to chewing cycle levels) in kinematics of chewing in two species of primates, Cebus and Macaca, while they feed on foods of known material properties. Variation in chewing kinematics was not evenly distributed among hierarchical levels. Most of the variation was observed among chewing cycles, most likely in response to changes in the external properties of the food bolus throughout the feeding sequence. Species differences were found in duration and vertical displacement during slow-close phase suggesting that each species exhibits different power stroke dynamics. Cebus exhibited more variable gape cycles than did Macaca, in particular when eating low-toughness foods. This increased ability to temporally and spatially modulate the gape cycle may reflect increased efficiency in processing food because Cebus monkeys use fewer, but longer cycles, than does Macaca when feeding on low-toughness foods. This is due to an increase in duration of the jaw-opening phases of the gape cycle, when the tongue repositions the food bolus in the oral cavity.
Cyclooxygenase inhibitors enhance tumour necrosis factor production and mortality in murine endotoxic shock

Abstract Intraperitoneal administration of E. coli lipopolysaccharide (5–15 mg/kg) produced a dose-related increase in mortality which was maximal 72 h after induction of shock. Using a suboptimal dose of LPS (10 mg/kg i.p.), pretreatment with indomethacin (0.1–10 mg/kg p.o) or ibuprofen (1–100 mg/kg p.o.) 30 min prior to induction of shock led to a significant enhancement of mortality. This enhancement was associated with a 2–3 fold increase in the peak circulating levels of tumour necrosis factor (TNF-α) in the serum of animals treated with indomethacin or ibuprofen compared to vehicle-treated control animals. These results indicate that TNF-α production is modulated by endogenous prostaglandins in vivo and that enhanced production of TNF-α by cyclooxygenase inhibitors may lead to exacerbation of some inflammatory processes.
Characterization of Mutants Affecting the KRK Sequence in the Carboxyl-terminal Domain of lac Repressor

The lac repressor carboxyl-terminal region is required for tetramer assembly and protein stability. To further investigate this region, especially the unusual sequence KRK, four deletion mutants eliminating the carboxyl-terminal 34, 35, 36, and 39 amino acids and five substitution mutants at the position of Arg-326, R326K, R326A, R326E, R326L, and R326W, were constructed using site-specific mutagenesis. The -34-amino-acid (aa) mutant, missing the most carboxyl-proximal lysine from the KRK sequence, exhibited lower affinity for both operator and inducer and lower protein stability than dimeric proteins studied previously. The -35-aa mutant with RK missing, as well as -36 aa and -39 aa, for which the entire KRK sequence was deleted, yielded inactive polypeptides that could be detected only by monoclonal antibody for lac repressor. In the Arg-326 mutant proteins, operator binding affinity was decreased by approximately 6-fold, the shift in inducer binding at elevated pH was diminished, and protein stability was decreased. Dramatic decreases in protein expression and stability occurred with substitution at position 326 by glutamate, leucine, or tryptophan. These results suggest that Arg-326 plays an important role in the formation of the proper tertiary structure necessary for inducer and operator affinity and for protein stability.
Law and politics in Aztec Texcoco

List of tables, figures and maps Preface List of abbreviations and symbols 1. The setting and early history of Texcocan imperial development 2. The legal history of Texcocan 3. The structure of the Texcocan empire 4. The political and legal dynamics of Texcocan 5. Local-level organization in the Texcocan empire: the lower legal levels of Texcocan 6. The development and maturation of the Texcocan legal system: principles of Texcocan jurisprudence 7. Conclusion Appendices Notes Bibliography Index.
Dissecting the African Digital Divide: Diffusing E-Learning in Sub-Saharan Africa

Many countries identified with the developing world, such as those in sub-Saharan Africa, have been recipients of aid programs over the past five decades totaling billions of dollars and aimed at fostering social and economic development to achieve global parity with the industrialized world. Much of this activity has been focused on building capacity in the higher education sector, especially through the introduction and implementation of distance education delivery systems to move from print to electronic resources for teaching and learning. The conventional wisdom is that, despite these efforts, success will ultimately be compromised by the lack of available and affordable technology. In fact, the constraints imposed by culturally driven traditional educational practices, as well as lack of strategic planning and effective management, are at least as powerful barriers to change in this arena. Unless both indigenous and expatriate advocates, consultants and managers of online learning are able to integrate new systems and structures, whether modest or ambitious, with new instructional approaches, the consequence of much of their efforts is likely to be an overlay of impressive instructional technology that largely masks the continuation of colonial-era, print-dependent educational practices.
Myocardial Amino Acid Transport in the Isolated Rabbit Right Ventricular Papillary Muscle: GENERAL CHARACTERISTICS AND EFFECTS OF PASSIVE STRETCH

The amino acid analog, alpha-aminoisobutyric acid (AIB) has been used to study myocardial amino acid transport in the isolated rabbit right ventricular papillary muscle. Intracellular AIB accumulation is linear for 2 hours and reaches a plateau at 3 hours at an intracellular/extracellular concentration gradient of 3.4. Anoxia does not inhibit this process whereas simultaneous inhibition of aerobic and anaerobic metabolism inhibits AIB accumulation. Intracellular AIB accumulation follows Michealis-Menten kinetics with a Km of 6.8 x 10-3M and a Vmax of 6.6 µmoles. ml intracellular fluid-1. hour-1. Sodium ion is obligatory for the transport process whereas no absolute potassium or calcium requirement exists. Ouabain, 10-5M, inhibits AIB uptake. Myograph techniques were utilized to determine the effect on AIB accumulation of subjecting unstimulated papillary muscles to various degrees of passive stretch. Muscles incubated at any tension above zero developed a greater intracellular/extracellular fluid AIB concentration ratio than muscles incubated at zero tension. These data suggest that increased myocardial wall tension may be a mechanical stimulus capable of inducing adaptive changes in myocardial metabolism.
JAM-1 Regulation of Endothelial Cell Migration: Implications for Angiogenesis

Angiogenesis, the sprouting of new blood vessels from existing ones, is a complex process that is critical to normal growth and development, but which occurs only in very specific conditions in adults. However, abnormal angiogenic responses can arise during development (eg, hemangioma formation) and in a variety of disease states. These diseases include, but are not limited to cancers in which blood vessels develop to support tumor growth, psoriasis, pulmonary hypertension, arthritis, and vascular retinopathy that can occur in diabetes, sickle cell disease, and other disorders. Multiple therapeutic approaches with varying degrees of success have been or are being developed to limit angiogenesis. Conversely, approaches to promote angiogenesis or the related but distinct process of collateral formation are also of interest for limiting ischemic damage in conditions where insufficient blood supply contributes to the condition or limits recovery, such as in myocardial infarction, stroke and other neurodegenerative conditions, Crohn disease, and others.1 Thus, advances in our understanding of events that occur at a molecular level to regulate blood vessel formation are of interest in providing future therapeutic targets to control these events. See page 2165 Endothelial cells (ECs) form the innermost layer of most nacsent blood vessels (there are some exceptions, such as the cytotrophoblasts that line maternal arteries in the placenta2 and tumor cells that mimic ECs in some tumor blood vessels3). Angiogenesis involves an orchestration of events that …
Mini-Midvastus vs Standard Medial Parapatellar Approach: A Prospective, Randomized, Double-Blinded Study in Patients Undergoing Bilateral Total Knee Arthroplasty

The purpose of this study was to determine whether the mini-midvastus approach to total knee arthroplasty (TKA) results in differences in quadriceps muscle strength as well as previously cited advantages in a double blind prospective randomized trial. Twenty-seven patients (54 TKAs) scheduled for bilateral TKA were randomized to undergo mini-midvastus approach on one knee and standard approach on the other. Incision lengths were the same. Postoperative strength was determined by isokinetic and isometric peak torque testing. Range of motion, pain Visual analog scale, side-preference, and gait analysis were assessed preoperatively and postoperatively. The only significant difference in strength testing was increased isokinetic and isometric extension torque at 3 weeks postoperatively for the mini-midvastus approach. No differences between the mini-midvastus and standard approach were observed for stride length, stance time, pain Visual analog scale, or knee range of motion. The mini-midvastus approach has limited benefit compared to the standard approach for TKA.
Glutathione S-transferase M1 modulates allergen-induced NF-κB activation in asthmatic airway epithelium.

Background Glutathione S-transferase M1 (GSTM1) is a phase II enzyme and regulator of inflammatory signaling in airway epithelial cells. We have found upregulation of neutrophilic airway inflammation in atopic asthmatics expressing GSTM1 gene (GSTM1+) compared to GSTM1null asthmatics. We hypothesized that GSTM1 modulates NF-κB activation in bronchial epithelium in atopic asthmatics. We determined regulation of allergen-induced NF-κB activation in bronchial epithelium by GSTM1 in human atopic asthmatics in vivo. Methods Endobronchial biopsies and bronchoalveolar lavage fluid samples were collected from 13 GSTM1+ and 12 GSTM1null human atopic asthmatics at baseline and 24 h after segmental allergen challenge. A quantitative analysis of NF-κB activation in airway epithelium was accomplished using a polyclonal antibody against the phosphorylated p65 component of NF-κB. Elastase-positive neutrophils in the bronchial wall were quantified. Results Postallergen neutrophilia in airway subepithelium and epithelial lining fluid was greater in GSTM1+ compared to GSTM1null asthmatics. Airway eosinophilia was similar in GSTM1+ and GSTM1null asthmatics. Allergen-provoked NF-κB induction in bronchial epithelium was significantly greater in GSTM1+ compared to GSTM1null asthmatics. Activation of NF-κB activation in airway epithelial cells correlated with interleukin-8 concentrations and absolute neutrophil numbers in bronchoalveolar lavage fluid in GSTM1+ but not GSTM1null asthmatics. Conclusions Allergen-induced neutrophilic airway inflammation in GSTM1+ asthmatics is associated with NF-κB activation in airway epithelial cells in vivo. These novel data provide a potential mechanism of the genomic link between GSTM1 polymorphism and airway neutrophilia in atopic asthma.
Infants Are Rational Constructivist Learners

What is the nature of human learning, and what insights can be gained from understanding early learning in infants and young children? This is an important question for understanding the human mind, the origins of knowledge, scientific reasoning, and how to best structure our educational environment. In this article, we argue for a new approach to cognitive development: rational constructivism. This view characterizes the child as a rational constructive learner, and it sees early learning as rational, statistical, and inferential. Empirical evidence for this approach has been accumulating rapidly, and a set of domain-general statistical and inferential mechanisms have been uncovered to explain why infants and young children learn so fast and so well.
Cell Specificity and Developmental Variation in the Targeting Pathways of FRT Cells

The polarity of epithelial cells is established gradually with time and different markers polarize at different rates (Balcarova et al., 1984). Recent data suggest that the molecular mechanisms by which proteins are delivered to the plasma membrane varies in cells derived from different tissues (Lisanti et al.1989; Le Bivic et al.1990 a,b; Matter et al.1990; Bartles et al.1990). It was previously shown that DPPIV follows an indirect route to the apical surface in liver cells (Bartles et a1.1990) and in the human intestinal cell line Caco-2 (Matter et al.1990), but when transfected into MDCK cells, DPPIV is vectorially targeted to the apical surface (Casanova et al. 1991; Low et al. 1991).
Cineangiography in the diagnosis of aortic dissection

To assess the ability of biplane cineangiography in the diagnostic evaluation of acute dissection of the aorta, 20 patients with acute dissection were studied within 24 hours of surgery or autopsy, or both. Biplane large film aortic angiography was performed in 11 patients (Group I) and biplane aortic cineangiography in 9 (Group II). The morphology of the aortic valve was defined precisely in 5 (50 percent) of 10 patients in Group I and in all 9 patients (100 percent) in Group II (p < 0.02). Aortic regurgitation was diagnosed in all patients in both groups in whom it was present (p = not significant). Intimai tears were localized in 5 (50 percent) of 10 patients in Group I and in 8 (89 percent) of 9 in Group II (p < 0.07). Intimal flaps were not identified angiographically in three patients in Group I and were identified in four patients (100 percent) in Group II (p < 0.01). The presence of retrograde dissection was established in three (38 percent) of eight patients in Group I and in four (100 percent) of four patients in Group II (p < 0.05). There was no difference in the ability to identify a nonclotted false lumen between cine and large film angiography. It is concluded that in addition to improved diagnostic capabilities, technical advantages make cineangiography a good alternative to large film angiography in the diagnostic evaluation of patients with acute dissection of the aorta.