cssi/SciSciGPT-SciSciNet huggingface dataset:
Beyond Class Hours: The GIS Lab as a Center of Geographic Education

Much has been written regarding the effectiveness of different teaching styles; however, considerably less has been written about the physical design of computer classrooms and their implications on education. To date, nothing has been written regarding building an informal learning community within a computer classroom, particularly outside of formal class hours. In this paper, the author examines designing an environment in which geography students feel at home, that is, a center of geographic education. Such a center could be defined as a place where students and faculty congregate to create and transmit geographic knowledge. A GIS lab can be such a place if deliberate care and effort are taken to ensure that the lab is multidisciplinary, dynamic, encourages creativity and discourse, and is a think tank for solving geospatial problems. This paper illustrates some proven methods for building such an environment.
Likelihood of missed and recurrent adenomas in the proximal versus the distal colon

Background Colonoscopy may be less efficacious in reducing colorectal cancer mortality in the proximal compared with the distal colon. A greater likelihood for missed and recurrent adenomas in the proximal colon may contribute to this phenomenon. Objective To examine whether a proximal adenoma is associated with the risk and location of missed and recurrent adenomas. Design Prospective. Setting Polyp Prevention Trial. Participants A total of 1864 patients with an adenoma at baseline underwent a follow-up colonoscopy 4 years later (adenoma recurrence). Of these, 1731 underwent a clearing colonoscopy 1 year after the baseline examination (missed adenoma). Main Outcome Measurements Association of baseline adenoma location with the risk and location of adenomas found at colonoscopy performed 1 year and 4 years later. Results At the year 1 colonoscopy, 598 patients (34.6%) had an adenoma (missed adenoma). Compared with those with a distal-only adenoma at baseline, patients with a proximal-only adenoma at baseline were more likely to have any missed adenomas (relative risk [RR] 1.28; 95% CI, 1.09-1.49) and a proximal-only missed adenoma (RR 2.05; 95% CI, 1.49-2.80). At the year 4 colonoscopy, 733 patients (39.3%) had adenoma recurrence. Patients with a baseline proximal-only adenoma were more likely to have any adenoma recurrence (RR 1.14; 95% CI, 1.00-1.31) and a proximal-only adenoma recurrence (RR 1.52; 95% CI, 1.15-2.02). Sensitivity analyses involving missed adenomas did not materially affect the risk or location of recurrent adenomas at year 4 colonoscopy. Limitation Lesions may still be missed on repeated colonoscopies. Conclusions Missed and recurrent adenomas are more likely to be in the proximal colon.
Anticipating the Future: Reconsidering The Philosophy of the Present

George Herbert Mead's Mind, Self, and Society (1934) appears on a majority of graduate theory syllabi, firmly established by Blumer and other symbolic interactionists as one of sociology's classics despite having been assembled from lecture notes by Mead's students from the University of Chicago. In the first few pages of the introduction to that book, we learn that many, perhaps the majority, of Mead's great thoughts were never recorded for posterity. His ongoing engagement with new ideas throughout his life did not slow for consummation in print-the task left to his students-and his sudden death prevented an opportunity to do otherwise. But few of us pause long enough to learn that Mind, Self, and Society is not the sole representative of those thoughts and that three additional volumes of Mead's lectures exist: The Philosophy of the Present (1932), Movements of Thought in the Nineteenth Century (1936), and The Philosophy of the Act (1938). Like Mind, Self, and Society, these three books are compiled from lecture notes and essays in various stages of completion, each by a different editor.4
Lyophilized platelets: continued development

In our initial investigation of functionality of platelets freeze-dried after stabilization with 1.8% paraformaldehyde, we found that the rehydrated cells were morphologically intact and retained adhesive and procoagulant properties. Further testing of fixed, washed freeze-dried platelets has demonstrated the physiologic nature of their adhesion in vitro and their hemostatic efficacy in vivo in correcting the bleeding time in thrombocytopenic animal models. Binding studies with monoclonal antibodies and radiolabelled ligands indicate an intact GpIb vonWillebrands factor receptor as on fresh platelets, but a somewhat attenuated GpIIbIIIa fibrinogen receptor. Repeated infusion of canine lyophilized platelet preparations in a single recipient over several months has shown no incipient cytopenia upon infusion of new doses nor accelerated clearance of platelets. These findings suggest minimal risk of systemic thrombosis or severe immunogenic reaction and support the notion of approaching clinical trials as soon as possible.
The effect of carbon surface functionality on tetrafunctional epoxy resin–diaminodiphenylsulfone cure reactions

Acidic functionality on the surface of oxidized carbon blacks modifies the cure processes of the tetrafunctional epoxy resin MY720 (largely tetraglycidyldiaminodiphenylmethane, TGDDM) crosslinked with diaminodiphenylsulfone (DDS). In the early stages of the cure (up to 60 min at 140°C), the rate of consumption of TGDDM and DDS and the rate of production of the 1 : 1 adduct are increased, together with an increase in the production of ether functionality. These chemical changes are associated with an increase in exotherm. an increase in gel fraction, and preferential adsorption of the amine curing agent on the carbon surface. During the middle stages of the cure (after 180 min at 140°C), the acidic carbon black has a slight retarding effect on the cure; but, on completion of the later stages of the cure, the effect of the carbon surface functionality diminishes, and, in contrast to earlier studies with difunctional epoxy resins, neither the total cure exotherm nor the final glass transition temperature is affected greatly. We attribute this difference to the greater ease of etherification reactions for the tetrafunctional resin compared to the difunctional case. Basic functionality on the surface of carbon black (induced by carbon dioxide treatment) has a slight retarding effect on TGDDM consumption in early stages of the cure. Less adsorption occurs on the basic carbon than on the acidic carbon, and the adsorbed material appears to be rich in resin. These results imply that treated carbon surfaces may advance or retard the local cure state of an MY720–DDS matrix, but will not affect markedly the final cure state.
Character analysis: an empirical approach applied to advanced snakes

Fifty characters of extant advanced snakes were selected for phyletic analysis, with the primary aim of determining evolutionary paths of the venomous taxa. The characters chosen showed roughly equivalent variation. States of characters were distinguished with reference to range of variation at species and generic levels. The heterogeneous, widespread and abundant family Colubridae was designated as representing the ancestral group. Direction of change in states was then determined by reference to colubrid conditions. Criteria used for judgement of direction were (1) uniqueness, (2) relative abundance, (3) correlation of derived states, (4) morphological specialization, (5) ecological specialization, (6) geographic restriction, (7) closely related taxa, and (8) correlation of applicable criteria. Two other criteria, (9) genetic structure and (10) fossil record, were not applicable. Characters used as examples of the approach are number of palatine teeth and the pattern of the head shields. In the latter, the derivative states are correlated with particular modes of life (aquatic, fossorial and terrestrial). The familial level taxa show rather different frequency distributions in respect to the four states of this character, with one derived state unique to the viperids. The second character, number of palatine teeth, was divided into classes by using a span covering most intraspecific variation. The resulting classes were lumped into four states emphasizing the classes of low numbers of teeth. The extreme derived states are correlated in the colubrids with distinctive modes of life (burrowing and digging) and with functional morphological specializations. The distribution of the states shows a trend toward low numbers of teeth in all the venomous families.
Dynamic stability of reinforced composite cylindrical shells in thermal fields

The dynamic stability of thin, multi-layered composite shells reinforced by axial and ring stiffeners and subjected to pulsating loads acting in the axial direction is considered. The presence of a thermal field is shown to affect the location of dynamic instability regions in the load amplitude-frequency plane. The boundaries of these regions can be evaluated as functions of static critical loads, natural frequencies, and thermal terms; the latter can be easily calculated. This permits straightforward conclusions to be drawn regarding dynamic stability of shells for which the buckling and free vibration problems have already been solved.
Attraction of A Native Florida Leafminer, Phyllocnistis Insignis (Lepidoptera: Gracillariidae), to Pheromone of an Invasive Citrus Leafminer, P. Citrella: Evidence for Mating Disruption of a Native Non-Target Species

We collected a native North American species, Phyllocnistis insignis (FreyB Sapindales: Rutaceae) groves at 4 sites in southeastern Florida during 2012. Phyllocnistis insignis moths were found in pheromone-baited traps year round with a peak flight in May. In trials designed to evaluate mating disruption of P. citrella, application of triene (SPLAT CLM™) disrupted trap catch of P. insignis during a 9 week period following treatment in spring (825 mg triene/ha), but not winter (750 mg triene/ha). In a second experiment, application of triene (837 mg/ha) and a 3:1 blend of triene and diene (840 mg triene + 280 mg diene/ha, respectively) loaded onto rubber dispensers disrupted catch of male P. insignis during a 12 week period following treatment of 0.14 ha plots. Also, application of a 3:1 blend of triene and diene (764 mg + 253 mg/ha, respectively) formulated in SPLAT CLM disrupted trap catch of male P. insignis during a 4 week period following treatment in a 66 ha plot. In a third experiment, application of blend (837 mg triene + 278 mg diene/ha) reduced the incidence of trap catch to zero during a 16 week period following treatment of 0.87 ha plots. These data suggest that efforts to disrupt mating of P. citrella influence non-target populations of the congeneric leafminer species, P. insignis. View this article in BioOne
MKP-1 signaling events are required for early osteoclastogenesis in lineage defined progenitor populations by disrupting RANKL-induced NFATc1 nuclear translocation.

Abstract Cytokine-directed osteoclastogenesis is initiated in response to m acrophage c olony s timulating f actor (M-CSF) and r eceptor a ctivator of N F- κ B l igand (RANKL) to drive formation of osteoclasts (OC), large bone resorptive cells of hematopoietic origin. RANKL-induced signaling activates the MAPK pathways, which initiates nuclear translocation of the master regulator of osteoclast formation, transcription factor NFATc1. Proper control over these signaling events is essential to normal OC formation response to stimuli. MAPK phosphatase 1 (MKP-1), a serine and tyrosine phosphatase encoded by the gene Dusp1 , functions to dephosphorylate and subsequently inactivate MAPK (p38 and JNK) signaling essential in osteoclastogenesis. Here, we explored the role of MKP-1 during RANKL-driven osteoclastogenesis from defined (B220/CD45 − GR1 − CD11b lo/− CD115 + ) OC progenitor (dOCP) populations using WT and Dusp1 − / − global knockout mice. Sorted cells were driven to OC by M-CSF pre-treatment followed by RANKL stimulation for 3 days. OC formation and qPCR products were analyzed for maturation. Results indicate that Dusp1 −/− dOCP form less numerous, significantly smaller and less functional OC compared to WT controls. These data were corroborated by mRNA expression of the key OC genes, Nfatc1 and Tm7sf4 (DC-STAMP), which were significantly reduced in early osteoclastogenesis in OC progenitor from Dusp1 −/− mice. Intriguingly, our data reveals that MKP-1 may positively control OC formation in response to RANKL by regulating NFATc1 nuclear translocation. Collectively, this report supports the idea that MKP-1 signaling is essential in early osteoclastogenesis in response to RANKL-induced signaling.
Angiogenesis and capillary maturation phenotypes associated with the Edpm3 locus on rat chromosome 3.

The quantitative trait locus (QTL) Edpm3 is one of a group of additively acting QTL \responsible for the difference in estrogen-induced pituitary tumor growth between the tumor-susceptible F344 and tumor-resistant BN rat strains. The F344.BN-Edpm3BN rat strain was produced by moving the segment of rat Chr 3 between D3Mgh7 and D3Mgh13, which contains the Edpm3 QTL, from the BN strain into the F344 genetic background. In a previous study, we used this congenic line to find that the BN allele of the Edpm3 QTL reduces tissue mass and S-phase fraction in the estrogen-induced rat pituitary tumor. We now report on the use of this congenic line to investigate the linkage of Edpm3 to tumor angiogenesis. Contrary to expectation, the F344.BN-Edpm3BN strain has significantly greater angiogenic activity than does F344 in both treated and untreated rats. Microvessel count (MVC), perivascular space, and number of nonattached pericytes/pericapillary fibroblasts are all elevated in the pituitary by chronic estrogen treatment and their values are significantly greater in F344.BN-Edpm3BN than F344. Thus, although there is greater angiogenic activity in the pituitary of estrogen-treated F344.BN-Edpm3BN rats, there is a deficiency in capillary maturation compared with F344.
Effects of difficulty, specificity, and variability on training to follow navigation instructions

To study the relative merits of three training principles - difficulty of training, specificity of training, and variability of training - subjects were trained to follow navigation instructions to move in a grid on a computer screen. Subjects repeated and then followed the instructions by mouse clicking on the grid. They were trained, given a short distractor task, and then tested. There were three groups, each receiving different message lengths during training: easy (short lengths), hard (long lengths), and mixed (all lengths), with all subjects given all lengths at test. At test, the mixed group was best on most lengths, the easy group was better than the hard group on short lengths, and the hard group was better than the easy group on long lengths. The results support the advantages of both specificity and variability of training but do not support the hypothesis that difficult training of the form used here would lead to overall best performance at test.
Evidence for the transformation of polycyclic organic matter in the atmosphere

Abstract The ratios of 1-nitropyrene and hydroxynitropyrenes to inert marker species (fine particulate lead, selenium, and elemental carbon) were considerably higher at a remote site on Bermuda than in Delaware. The results suggested that these nitroaromatic POM are formed in atmospheric reactions. The ratio of benzo( a )pyrene to marker species was not significantly different at the two sites. This result did not reflect the expected loss of BaP in atmospheric photochemical reactions.
Clinical implications of pulmonary hypertension in mitral stenosis.

The relation of mean pulmonary arterial and mean left atrial pressure was examined in 200 patients with pure mitral stenosis and compared with that in a heterogenous group of 313 patients, including 27 with normal hemodynamic and angiographic findings, 40 with coronary artery disease, 106 with aortic stenosis, 73 with aortic insufficiency and 67 with mitral insufficiency. Linear regression analysis of mean pulmonary and left atrial pressures of the patients without mitral stenosis revealed nine patients with increased pulmonary pressure greater than 2 standard errors from the regression line. Three of these nine had acute pulmonary emboli, three had severe obstructive lung disease and one had severe congestive heart failure. Mean pulmonary and left atrial pressures were compared in the patients with mitral stenosis using the values for the regression line and standard error obtained from the patients without mitral stenosis. Thirty-seven of the 200 patients with mitral stenosis had increased pulmonary pressure greater than 2 standard errors from the regression line. Fifteen of these 37 patients (41 percent) demonstrated pulmonary emboli or severe obstructive lung disease as compared with 9 patients (4 percent) of the 164 patients with mitral stenosis within 2 standard errors. From these data we conclude that pulmonary arterial pressure markedly in excess of left atrial pressure is common in mitral stenosis and carries an implication of pulmonary thromboembolism or severe lung disease.
Endocannabinoids promote hepatic lipogenesis and steatosis through CB1 receptors

Endogenous cannabinoids acting at CB1 receptors stimulate appetite, and CB1 antagonists show promise in the treatment of obesity. CB1−/− mice are resistant to diet-induced obesity even though their caloric intake is similar to that of wild-type mice, suggesting that endocannabinoids also regulate fat metabolism. Here, we investigated the possible role of endocannabinoids in the regulation of hepatic lipogenesis. Activation of CB1 in mice increases the hepatic gene expression of the lipogenic transcription factor SREBP-1c and its targets acetyl-CoA carboxylase-1 and fatty acid synthase (FAS). Treatment with a CB1 agonist also increases de novo fatty acid synthesis in the liver or in isolated hepatocytes, which express CB1. High-fat diet increases hepatic levels of the endocannabinoid anandamide (arachidonoyl ethanolamide), CB1 density, and basal rates of fatty acid synthesis, and the latter is reduced by CB1 blockade. In the hypothalamus, where FAS inhibitors elicit anorexia, SREBP-1c and FAS expression are similarly affected by CB1 ligands. We conclude that anandamide acting at hepatic CB1 contributes to diet-induced obesity and that the FAS pathway may be a common molecular target for central appetitive and peripheral metabolic regulation.
Excited-state chiral discrimination in aqueous solutions of lanthanide(III) : 2,6-pyridinedicarboxylate complexes

Addition of resolved-Ru(phenanthroline) 3 2+ to aqueous solutions of racemic complexes of Ln(2,6-pyridinedicarboxylate) 3 3- (where Ln = Eu(III) and Tb(III) results in efficient quenching of lanthanide emission. The terbium complex is quenched more than the europium complex illustrating the importance of electronic overlap. The emission is also circularly polarized indicating that the quenching mechanism is enantioselective. Comparison with previous data allows for the identification of the enantiomer in excess, and, thus, of the favored enantioselective energy transfer pair.
Hypertensive changes within the aortic arch of infants and children with isolated coarctation

Background Despite repair, a significant proportion of patients with coarctation of the aorta (CoA) present with late hypertension. Increased gene expression of aortic wall collagen and vascular smooth muscle cell markers occurs in the presence of hypertension. Before repair, a patent ductus arteriosus (PDA) limits hypertension proximal to the coarctation. We hypothesize that preoperative collagen and vascular smooth muscle expression from the aortic arch in children is variable, depending on the presence or absence of a PDA. Methods We analyzed the expression patterns of collagen and vascular smooth muscle cell markers in 25 children with CoA using a quantitative polymerase chain reaction. Aortic arch tissue proximal to the CoA was normalized to descending aortic tissue distal to the coarctation. Collagen-I, transforming growth factor-β, elastin, and calponin were analyzed. Results At repair, 19 patients were aged younger than 3 months (14 with a PDA, 5 with a ligamentum arteriosum), and the remaining 6 were older than 1 year. There was no difference in age or weight between infants with or without a PDA. Infants without a PDA had the greatest difference in collagen-I expression compared with infants with a PDA (7.0 ± 1.6-fold vs 0.8 ± 1.1-fold, p = 0.01). Expression of transforming growth factor-β (4.3 ± 1.4 vs 2.6 ± 2.3, p = 0.01) and calponin (3.7 ± 0.7 vs 0.6 ± 1.1, p = 0.05) was lower from infants with vs without a PDA. Conclusions Our findings provide evidence of preoperative changes in the aortic arch before repair, particularly in the absence of a PDA.
Saline soak tests to determine the short-term reliability of an in situ thin film resistance temperature detector.

Abstract With an objective to assess the short-term reliability of thin film, encapsulated resistance temperature detectors (RTDs) in corrosive environments, these were placed in aqueous soak solutions of double de-ionized water (DDI) and phosphate buffered solution (PBS) or saline for eight weeks. They were removed weekly in order to characterize the effects of the solutions on their electrical properties, as well as their thermal response. The solutions were analyzed weekly as well with an FT-IR spectrometer in order to determine if chemical reactions took place during the soak tests and optical micrographic studies were carried out too. The RTDs appeared not to suffer degradation during the period of study. Nonetheless, it turned out that the soak tests offer a user-friendly and safe approach to remove the Benzocyclobutene (BCB) layer; this is an issue that is likely to be of some interest in the electronics fabrication community.
First Field Conference of Billings Geological Society: ABSTRACT

The first field conference of the Billings Geological Society was held on September 15, 16, and 17, 1950. The conference featured a three-day trip into the beautiful mountainous region of southwestern Montana where early American geologists first studied and named many of the rock formations now recognized in the northern Rocky Mountains. The travel route led westward from the structurally simple plains region of central Montana up the Yellowstone River valley between thick piles of volcanic rocks resting on pre-Cambrian and Paleozoic formations in the Yellowstone Plateau and Beartooth Mountains on the south and the dike- and sill-riddled Cretaceous rocks that form the Crazy Mountains on the north. Thence the route crossed the zone of complexly faulted and folded mountain and valleys at the eastern edge of the Rocky Mountains province and approached the crumpled eastern margin of the old Cordilleran geosyncline where Paleozoic and lower Mesozoic rock formations from the plains region begin to thicken greatly and change in lithology. In this region of rough topography and complex geology, distances between points of geologic interest are relatively short. Stops were made at excellent exposures of rocks belonging to every period of geologic time, except the Silurian, from pre-Cambrian to Cretaceous, and lecturers called attention to the principal geologic features and compared them with features seen at other stops. A compact well illustrated and clearly printed guidebook furnished road logs for each day's travel as well as interesting comments on geologic and historic points that could be seen between the stops. The guidebook also contained nine short informative articles by "men who know Montana geology best" on stratigraphy, oil geology, mining geology, and engineering geology. End_of_Article - Last_Page 1106------------
The type A (coronary-prone) behavior pattern, aging, and mortality.

: Young and middle-aged persons displaying the Type A (coronary-prone) behavior pattern have been shown repeatedly to be at substantially increased risk of coronary heart disease. A review of recent empirical research regarding adaptability and survival among the elderly suggests the hypothesis that the clinical significance of Type A behavior may shift radically in old age. Thus, compared to Type B (not coronary-prone) subjects, Type As may be at lesser rather than greater risk of impairment and death.
Bacterial endophthalmitis resulting from radial keratotomy.

Staphylococcus epidermidis endophthalmitis developed nine days after surgery in a 47-year-old man who underwent a 16-incision radial keratotomy during which the cornea was inadvertently perforated. The anterior chamber showed marked cellular reaction and flare and there was a 5% hypopyon inferiorly. There was also a marked cellular reaction in the vitreous, which contained many fluffy white balls. Visual acuity decreased to counting fingers at 1 foot. A pars plana vitrectomy and intraocularly, periocularly, intravenously, and topically administered antibiotics resulted in recovery of the visual acuity to 6/9 (20/30).
Influence of amino acid availability on protein turnover in perfused skeletal muscle.

Abstract The effects of amino acids on protein turnover in skeletal muscle were determined in the perfused rat hemicorpus preparation. Perfusion of preparations from fasted young rats (81±2 g) with medium containing either a complete mixture of amino acids at five times (5×) their normal plasma levels, a mixture of leucine, isoleucine, and valine at 5× or 10× levels, or leucine alone (10×) resulted in a 25–50% increase in muscle protein synthesis and a 30% decrease in protein degradation compared to fasted controls perfused in the absence of exogenously added amino acids. When the branched-chain amino acids were omitted from the complete mixture, the remaining amino acids (5×) had no effect on protein turnover. The complete mixture at 1× levels was also ineffective. Comparison of the effects of amino acids with those of glucose and palmitate indicated that amino acids were not acting by providing substrates for energy metabolism. The stimulatory effect of amino acids on protein synthesis was associated with a facilitated rate of peptide-chain initiation as evidenced by a relative decrease in the level of ribosomal subunits. This response was not as great as that produced by insulin, and the amino acids did not augment the effect of insulin. Although protein synthesis in preparations from fed young rats (130±3 g) was stimulated by the addition of a mixture of the branched-chain amino acids (5×) to about the same extent as that observed in the fasted young rats, protein degradation was not affected. Furthermore, neither synthesis nor degradation were affected in preparations from fasted older rats (203±9 g) suggesting that the age and or nitritional state of the animal may influence the response of skeletal muscle to altered amino acid levels.
Fatigue crack growth behavior of titanium alloys

Abstract Fatigue crack growth behavior of titanium alloys is examined using the Unified Approach developed by the authors. The approach is based on the realization that fatigue requires two load parameters for unambiguous description. This requirement manifests as two fracture mechanics parameters: maximum stress intensity factor, K max , and stress intensity amplitude, Δ K . The former essentially governs the breaking of the bonds contributing to crack growth, while the latter controls the extent of cyclic damage required ahead of the crack tip. The former can also be associated with the monotonic plastic zone, while the latter with the cyclic plastic zone. The crack growth behavior in Ti-alloys is complicated by several factors such as microstructure and its dependent flow properties, planarity and heterogeneity of slip, environmental sensitivity of the alloy, and changes in the flow behavior due to segregation of internal hydrogen contributing to localized creep and embrittlement. In the past, several anomalies in the behavior have been noted. The Unified Approach demonstrates that these observed anomalies are closely related to changes in the mechanisms of crack growth due to synergistic effects of mechanical and chemical driving forces. Crack growth trajectory maps developed under the Unified Approach document these changes in the mechanisms that occur with increasing crack growth rate or stress intensity.
Magnetic Properties of Atomic Clusters of the Transition Elements

Atomic clusters are aggregates of atoms containing from a few to several thousand atoms. Their properties are different from those of the corresponding bulk material because of the sizable fraction of atoms forming the cluster surface. Many differences between clusters and bulk materials originate from the small volume of the potential well confining the electrons in the clusters. In such cases, the electrons of clusters fill discrete levels, instead of having the continuous distribution (bands) characteristic of the solid. How many atoms are required for a cluster to show the properties of the macroscopic material? This important question still lacks a convincing answer. By studying the properties of clusters, scientists expect to obtain information on the early stages of growth of condensed matter and on the evolution of the chemical and physical properties as a function of cluster size. Knowing something about the evolutionary patterns of clusters may have interesting technological implications. For instance, the melting temperature of small particles decreases linearly as a function of the inverse particle radius 1/R. This decrease affects sintering processes, in which fine powders are compressed and heated until the particles coalesce: Lower sintering temperatures will be required for particles with very
Wnt signaling promotes hematoendothelial cell development from human embryonic stem cells

Human embryonic stem cells (hESCs) provide an important means to effectively study soluble and cell-bound mediators that regulate development of early blood and endothelial cells in a human model system. Here, several complementary methods are used to demonstrate canonical Wnt signaling is important for development of hESC-derived cells with both hematopoietic and endothelial potential. Analyses using both standard flow cy-tometry, as well the more detailed high-throughput image scanning flow cytometry, characterizes sequential development of distinct early developing CD34brightCD31+Flk1+ cells and a later population of CD34dimCD45+ cells. While the CD34brightCD31+Flk1+ have a more complex morphology and can develop into both endothelial cells and hematopoietic cells, the CD34dimCD45+ cells have a simpler morphology and give rise to only hematopoietic cells. Treatment with dickkopf1 to inhibit Wnt signaling results in a dramatic decrease in development of cells with hematoendothelial potential. In addition, activation of the canonical Wnt signaling pathway in hESCs by coculture with stromal cells that express Wnt1, but not use of noncanonical Wnt5-expressing stromal cells, results in an accelerated differentiation and higher percentage of CD34brightCD31+Flk1+ cells at earlier stages of differentiation. These studies effectively demonstrate the importance of canonical Wnt signaling to mediate development of early hematoendothelial progenitors during human development.
Economic analyses of diagnostics for tuberculosis: what's the point?

In the last 5 years, an unprecedented number of novel tests for tuberculosis (TB) have been approved for global use by the WHO [1], including the highly publicized Xpert® MTB/RIF assay (Cepheid, In...
Making the continuing medical education lecture effective

AbstractAlthough the lecture appears to be synonymous with continuing medical education (CME), the effectiveness of lecture-based CME remains in question. Despite conflicting data, the lecture continues to be widely used in the delivery of CME. This study was conducted to identify the attributes of
Yolk testosterone and estradiol variation relative to clutch size, laying order and hatching asynchrony in Common Grackles

Maternal effects are typically thought to enhance rather than reduce offspring performance, but asynchronous hatching (ASH) in birds typically produces a size hierarchy within a clutch that frequently reduces the growth and survival of nestlings from eggs that hatch later. Given that yolk steroids can significantly affect offspring phenotype and that in many species the levels of yolk steroids have been found to increase with laying order, the maternal transfer of steroids to egg yolk has been proposed as a mechanism for females to offset the deleterious effects of ASH. To test this hypothesis, we determined whether yolk steroids varied with laying order or clutch size in Common Grackles (Quiscalus quiscula). Because ASH varies with clutch size (hatching span averages 48 h in five-egg clutches, 24 h in four-egg clutches) and regularly results in the starvation of later hatched nestlings, we predicted: (1) testosterone and 17s-estradiol levels should increase with laying order in both clutch sizes to mitigate the negative effects of ASH on last-hatched nestlings, and (2) the increase should be greater in five-egg clutches due to more pronounced hatching asynchrony. Using a competitive-binding steroid radioimmunoassay, we found no systematic variation in either testosterone or estradiol levels relative to laying order or clutch size. In the absence of evidence that yolk steroids interact adaptively with ASH, research must look elsewhere for potential benefits that might compensate for the costs these steroids impose on nestlings.
Attitudinal and behavioral correlates of coronary heart disease

Abstract The recognition of an association between coronary heart disease (CHD) and coronary prone behavior (CPB) has raised the question of whether behavior may directly affect coronary atherosclerosis. The relationship of coronary occlusion measured by arteriography and angina pectoris to questionnaire responses selected as consistent with the attitudes and behavior of CPB were examined retrospectively in 2215 employed male patients. Nonbehavioral factors such as serum cholesterol and triglycerides were highly related to occlusion but not to angina. By comparison, most subjective attitudes and some quantitative behaviors consistent with CPB were overrepresented in angina but not in occlusion. Certain neurotic behaviors were also disproportionately represented in angina but not in occlusion. These results indicate that attitudinal and behavioral aspects of CPB contribute to angina pectoris and perhaps indirectly to atherosclerosis. This association was greatest in patients older than 50 years, but comparable to some standard risk factors in younger patients also.
Rapid Synthesis and Screening of Chemically Activated Transcription Factors with GFP-based Reporters

Synthetic biology aims to rationally design and build synthetic circuits with desired quantitative properties, as well as provide tools to interrogate the structure of native control circuits. In both cases, the ability to program gene expression in a rapid and tunable fashion, with no off-target effects, can be useful. We have constructed yeast strains containing the ACT1 promoter upstream of a URA3 cassette followed by the ligand-binding domain of the human estrogen receptor and VP16. By transforming this strain with a linear PCR product containing a DNA binding domain and selecting against the presence of URA3, a constitutively expressed artificial transcription factor (ATF) can be generated by homologous recombination. ATFs engineered in this fashion can activate a unique target gene in the presence of inducer, thereby eliminating both the off-target activation and nonphysiological growth conditions found with commonly used conditional gene expression systems. A simple method for the rapid construction of GFP reporter plasmids that respond specifically to a native or artificial transcription factor of interest is also provided.
Telepsychiatry in Private Practice

Telepsychiatry is being increasingly adopted in private practice and is predicted to play an important role in increasing access to care in rural communities and other underserved areas. With the current level of need, it is unlikely that all of the required services can be fully met through existing telepsychiatry practitioners. Thus, in light of this new research and the significant needs of rural communities, some of the historical barriers to using telepsychiatry in private practice can be overcome through the use of new technology and sound financial modeling. This article examines historical barriers to adopting telepsychiatry in private practice and offers adaptations based on a large case series derived from the clinical practice of the author as well as a review of scientific literature on telepsychiatry.
The social construction of a secure, anonymous electronic payment system : frame alignment and mobilization around Ecash

This paper examines public discourse in order to illuminate the processes by which issues of anonymity, surveillance, security, and privacy are integrated into public understandings of, and interactions with, consumer payment systems. Using theories of the social construction of technology, and Gamson's model of issue construction, it analyses the issue package deployed by the developer of the Ecash electronic payment system. An issue package is a set of framing devices which focus and constrain discussion of a particular issue. The paper then analyses three different discursive sites (print media, US Congressional deliberation, and an electronic mailing list) to gauge the success of that package, according to its presence and its resonance within each site. Using theories of frame alignment and social mobilization, the package is identified as a globalizing framing strategy. Its failure is explained by the difficulties a frame of such structure will have in meshing with the discursive practice of each site, in resonating with cultural themes of each site, and in provoking social action.
RANGE MEASUREMENT AND PARTICLE IDENTIFICATION IN A PLATE-LOADED FILAMENTARY CHAMBER

A plate-loaded filamentary chamber consisting of 104 alternate iayers of 1-mm dia plastic scintillator filaments and Au plates of approximately 1.5 g/cm/ sup 2/ was used to measure the ranges and identify particles arising from the decay modes: K/sup +/ and up to st r e (as Fe/sup 59 /sup +/ + e (as Fe/sup 59 /sup 0/ and K/sup +/ and up to / + /sup +/ + . Two range spectra were obtained: one including both muons and pions and one exhibiting almost exclusively particles recognized as e (as Fe/sup 59 /sup +/ from K/sup +/ and up to st r e (as Fe/sup 59 /sup +/ + e (as Fe/sup 59 /sup 0/ byff their decay. (A.G.W.)
Synthesis of vaccinia virus thymidine kinase in microinjected Xenopus oocytes

Abstract Messenger RNA was extracted from vaccinia virus (VV) -infected thymidine kinase (tk)-deficient cells early in infection and introduced into the cytoplasm of Xenopus laevis oocytes by microinjection. Extracts prepared from these oocytes after 24 hr incubation exhibited a thymidine kinase activity that was more than 250-fold greater than the endogenous oocyte level. Messenger RNA extracted late during VV infection, or from cells infected with a tk − mutant of VV, failed to direct the increase in tk activity. The enzyme synthesized in oocytes appeared to be identical to authentic VV tk from infected human tk − cells by the criteria of thermal inactivation kinetics, sedimentation velocity, and electrophoretic mobility under nondenaturing conditions. Moreover, tk synthesis was specifically arrested if, prior to microinjection, the early VV mRNA was hybridized to a recombinant plasmid that contained the VV tk gene. However, attempts to detect the synthesis of VV tk in Xenopus oocytes which had been injected intranuclearly with VV DNA fragments containing the tk gene were uniformly unsuccessful.
A numerical study of the mechanical response to excavation and ventilation around tunnels in clay rocks

Abstract As an attempt to more accurately model the nonlinear-elastic response and excavation damaged zone (EDZ) behavior induced by excavation and ventilation in clay/shale, we have incorporated and implemented a recently developed stress–strain relationship, called the two-part Hooke's model (TPHM), within the TOUGH–FLAC3D code. TPHM is based on a macroscopic-scale approximation using a natural-strain-based Hooke's law to describe elastic deformation for a fraction of pores subject to a large degree of deformation; an engineering-strain-based Hooke's law is used for the other part. We carried out a series of numerical verification tests on the deformation behavior of small-scale clay and shale samples based on TPHM. A comparison with an elastic model described by the conventional Hooke's law (the single-part Hooke's model, SPHM) indicates that the TPHM can more accurately capture observed mechanical deformation in the low-stress region of clay/shale rocks. Furthermore, based on numerical simulations of elastic response and EDZ behavior around a tunnel opening (in Opalinus Clay) induced by excavation and ventilation, we found a larger radial elastic deformation on the roof and floor of the tunnel, and considerably different stress distributions than were found with SPHM. Although desaturation was influenced by ventilation only and occurred within a narrow zone around the tunnel opening, a suction state in the rock mass developed over quite a long radial distance, which had a substantial effect on the macroscopic behavior of the rock matrix during the desaturation process. Throughout the tunnel, the mode and extension of damage zones calculated by TPHM showed clear differences from those calculated by SPHM. The results based on TPHM are more consistent with observations, indicating the need and importance of incorporating more accurate constitutive models for modeling coupled processes.
Melting Point of Chromium

No accurate determination of the melting point of chromium has been published recently, so far as we are aware, and the accepted value of 1550° C. usually quoted appears to be based on measurements made in 1907–8.
Factor Structure of Patient and Caregiver Ratings on the Dementia Quality of Life Instrument

Preliminary evidence suggests that quality of life reports from patients diagnosed with mild cognitive impairment (MCI) and mild Alzheimer's disease (AD) are as reliable and valid as data provided ...
Angular momentum transfer in low velocity oblique impacts: Implications for asteroids

The efficiency of angular momentum transfer ζ in low velocity oblique impacts was studied experimentally. ζ is defined as the fraction of incident angular momentum transferred to the rotation of the target. Plaster, mortar, cement, and one granite target were studied. Lead and aluminum projectiles were used. Only cratering impacts were considered. ζ was found to decrease with increasing incidence angle φ (relative to the surface normal). For example, for impacts into cylindrical mortar targets a least-squares fit of the form ζ = A(cos φ)β with A = 0.9 and β = 1.7 was found to match the data points reasonably well. In addition, β decreased from 1.9 to 1.4 as the kinetic energy density ϵ (= kinetic energy of the projectile/projectile volume) increased from 0.5 to 1.8 × 10^9 J m^(−3). This suggests that more energetic impacts transfer angular momentum more efficiently. ζ decreased as the indentation hardness H of the target increased: at φ ∼ 35°, ζ = 0.07 for granite (H = 850 kg mm^(−2) and ζ = 0.7 for plaster (H = 7.5 kg mm^(−2)). Cement and mortar (H = 76 kg mm^(−2)) yielded intermediate values, although the values for cement (ζ ∼ 0.3) were appreciably lower than for mortar (ζ ∼ 0.6). In all cases where the velocity of the ricochetted projectile was determined, the fraction of angular momentum carried away by ejecta was found to be less than 30%. Finally, the results were only weakly dependent on the material of the projectile.
Temporal course of amnesia in rats after electroconvulsive shock

Abstract Immediately following one-trial passive avoidance training in a step-through apparatus, rats received a single electroconvulsive shock (ECS). Test trials 15, 30, 60 or 120 min later found retention at 15 min only. A second experiment replicated the 15 min retention effect and included a control group that indicated the phenomenon was not a systemic effect caused by the interaction of footshock and ECS. Other groups demonstrated that retention at 15 min, although appreciable, is not complete. Some implications for memory models are discussed.
The Politics of Knowledge: The Carnegie Corporation, Philanthropy, and Public Policy

The Carnegie Corporation, among this country's oldest and most important foundations, has underwritten projects ranging from the writings of David Riesman to Sesame Street. Lagemann's lively history focuses on how foundations quietly but effectively use power and private money to influence public policies.
The V(D)J Recombination Activating Gene, RAG-1

The RAG-1 (recombination activating gene-1) genomic locus, which activates V(D)J recombination when introduced into NIH 3T3 fibroblasts, was isolated by serial genomic transfections of oligonucleotide-tagged DNA. A genomic walk spanning 55 kb yielded a RAG-1 genomic probe that detects a single 6.6-7.0 kb mRNA species in transfectants and pre-B and pre-T cells. RAG-1 genomic and cDNA clones were biologically active when introduced into NIH 3T3 cells. Nucleotide sequencing of human and mouse RAG-1 cDNA clones predicts 119 kd proteins of 1043 and 1040 amino acids, respectively, with 90% sequence identity. RAG-1 has been conserved between species that carry out V(D)J recombination, and its pattern of expression correlates exactly with the pattern of expression of V(D)J recombinase activity. RAG-1 may activate V(D)J recombination indirectly, or it may encode the V(D)J recombinase itself.
Arachidonic acid reversibly enhances N-type calcium current at an extracellular site.

We examined the effects of arachidonic acid (AA) on whole cell Ca2+ channel activity in rat superior cervical ganglion neurons. Our companion paper (Liu L, Barrett CF, and Rittenhouse AR. Am J Physiol Cell Physiol 280: C1293–C1305, 2001) demonstrates that AA induces several effects, including enhancement of current amplitude at negative voltages, and increased activation kinetics. This study examines the mechanisms underlying these effects. First, enhancement is rapidly reversible by bath application of BSA. Second, enhancement appears to occur extracellularly, since intracellular albumin was without effect on enhancement, and bath-applied arachidonoyl coenzyme A, an amphiphilic AA analog that cannot cross the cell membrane, mimicked enhancement. In addition, enhancement is voltage dependent, in that currents were enhanced to the greatest degree at −10 mV, whereas virtually no enhancement occurred positive of +30 mV. We also demonstrate that AA-induced increases in activation kinetics are correlated with ...