cssi/SciSciGPT-SciSciNet huggingface dataset:
Diversity of modulation---a new concept in communication technology

A new concept called ‘diversity of modulation’ has been presented. Its purpose is to reduce the fading range of the signals received through a time-varying multipath transmission medium. A digital-communication system with N-order diversity utilising this concept has also been described, and its performance is compared with the conventional diversity systems.
Intramolecular epitope spreading induced by staphylococcal enterotoxin superantigen reactivation of experimental allergic encephalomyelitis

The staphylococcal enterotoxin superantigens are among the most potent T cell stimulators known. They have been shown to alter the course of disease in experimental allergic encephalomyelitis, an animal model for multiple sclerosis (MS). We have previously demonstrated that two of the staphylococcal enterotoxins, SEA and SEB, are able to reactivate paralysis in PL/J mice which had been immunized with myelin basic protein (MBP) and resolved an initial episode of paralysis. In PL/J mice, Ac1-11 is the dominant encephalitogenic determinant of MBP. We hypothesized that superantigen reactivation of experimental allergic encephalomyelitis (EAE) may result in the spreading of T cell specificities for other epitopes of MBP. PL/J mice which had resolved an initial episode of EAE were treated with SEA and developed a second episode of paralysis. At the onset of symptoms, mice were sacrificed and splenocytes were stimulated in vitro with a panel of MBP peptides. EAE reactivation by SEA resulted in the spreading of T cell specificites to residues 100 to 120 of MBP. While intramolecular spreading did occur, spreading to other antigens did not, as evidenced by the lack of response to a proteolipid protein (PLP) peptide and heat shock protein 60 (hsp 60). To further characterize the epitope MBP 100-120, PL/J mice were immunized with MBP 100-120. No initial development of disease was observed. However, administration of SEA 2 weeks after MBP 100-120 immunization resulted in the onset of paralysis. In addition to a proliferative response to MBP 100-120, these mice also exhibited a proliferative response to the flanking MBP peptides 81-100 and 120-140. Thus, SEA is able to induce intramolecular epitope spreading in PL/J mice after reactivation of EAE.
NONLINEAR AEROPREDICTION METHODOLOGY FOR ROLL POSITION OF 45 DEGREES

Abstract : The Naval Surface Warfare Center, Dahlgren Division Aeroprediction Code has been extended to the roll position of 45 deg (or fms in cross or orientation). New technology developed and discussed in this paper includes: wing-body and body-wing interference factors for this roll orientation and to angles of attack of 90 deg; approximate methods to estimate wing-alone center of pressure shift at high angles of attack and 45 deg roll position; and 'fm choking' at high Mach number. This new technology allows aerodynamics to be estimated with average accuracy levels of plus or minus 10 percent on normal and axial force coefficients and plus or minus 4 percent of body length on center of pressure. Exceptions to this are at subsonic Mach number and high angle of attack where wind tunnel sting interference effects are present, and at high Mach number and angle of attack where internal shock interactions from a forward fm onto an aft-mounted fm are present. Results are presented for several wing-body and wing-body-tail configurations at various Mach numbers and angles of attack to support this average accuracy level conclusion.
Kodu, alice and lego robotics: a three-step model of effective introducing middle school students to computer programming and robotics (abstract only)

This poster describes a three-step ladder model of K 12 computing and robotics instruction beginning with a simpler programming environment (Kodu) and progressing to more challenging frameworks (Alice and Lego NXT). While moving between the three steps, students explore the similarities and differences in how concepts such as variables, conditionals, and looping are realized. Computer Science Unplugged activities are integrated and then implemented using Kodu, Alice and robots. This innovative model helps maintaining high levels of motivation, concentration, and fun during the entire six weeks of the camp. Feedback obtained from instructors, participants and participants' parents, reinforced by the results of the pre and post program evaluations, clearly indicated the program as a success.
The Effect of Constructivist Teaching Approach on the Conceptual Understanding of Biology Students

This study determines the effect of constructivist-based teaching approach on the cognitive and affective levels of conceptual understanding of Marine Biology of BS Biology students. The study made use of the pre-test-posttest one-shot experimental design. The participants were selected using purposive sampling. Data and other information needed in this study were gathered mainly through conceptual understanding test, formal interviews and journals. And to treat these data, the mean scoring system and t-test for dependent samples were used. Results revealed that the extent of cognitive level of conceptual understanding in Marine Biology of the students based on their journals was observed to a very great extent. On the other hand, the extent of affective level of conceptual understanding of the students in Marine Biology as revealed in their journals was observed to a great extent. Moreover, the findings also showed that there is significant difference on the students' level of conceptual understanding based on their mean scores in the test after using the constructivist-based teaching approach. Lastly, it is also found out that the students learned and appreciated Marine Biology through constructivist-based teaching approach based on the interviews conducted to them.
Estimating species diversity in a guild of Neotropical skippers (Lepidoptera: Hesperiidae) with artificial lures is a sampling problem

Abstract. 1 Butterflies are frequently used to investigate Neotropical diversity, but the family Hesperiidae is almost never employed as a focal group. Sampling Hesperiidae with artificial lures has been used to assist in species richness estimates of males that use bird droppings as a resource, but its effectiveness for estimating total hesperiid site diversity is unknown. 2 This study characterises species richness and abundance in a diverse assemblage of Hesperiidae sampled at artificial lures. Sampled and estimated richness among taxonomic subsets were compared to the known site richness. These comparisons are used to assess artificial lures as a method for sampling total richness of Hesperiidae. We tested for potential differences in attraction in lures placed with and without the presence of army ant swarms. 3 Five years of intermittent sampling with lures recovered 65% of the known Hesperiidae species richness at the study site. We found the subfamilies were differentially attracted to lures, where 86% of Eudaminae, 56% of Hesperiinae and 55% of Pyrginae species known from the site were recovered by lures. Species accumulation and taxonomic diversity differed among lures placed alone, and those placed in the presence of army ants. 4 Our results suggest that sampling with artificial lures can be used to estimate diversity of Neotropical Eudaminae and a few tribes of Hesperiinae at some sites. Available evidence indicates that Hesperiidae feeding at bird droppings is predominately a Neotropical phenomenon. Finally, we conclude that estimating diversity in Neotropical Hesperiidae will require long-term studies that use multiple sampling techniques.
Oxidative Coupling of Methane on Oxygen-Semipermeable Yttria-Doped Bismuth Oxide Ceramics in a Reducing Atmosphere

Oxidative coupling of methane (OCM) on oxygen-semipermeable δ-phase 25 mol % Y2O3/Bi2O3 (BY25) in a reducing (methane) atmosphere was studied by measuring transient catalytic properties and weight change of the ceramics when exposed to a methane stream at high temperatures (>800 °C). Compared to the results obtained in a fixed-bed reactor operated in the cofeed mode, BY25 ceramics in a pellet form exhibit extremely high C2 selectivity (94%) and appreciable reactivity (C2 formation rate of 0.7 μmol/g·s for OCM in a highly reducing methane atmosphere. Experimental results are also reported to show the effects of temperature, flow rate, methane exposure time, helium purge time, and helium to methane ratio on catalytic properties of BY25 pellets in a methane atmosphere. The results indicate that BY25 ceramic membrane materials possess desired catalytic properties for OCM membrane reactor applications.
CRF in the paraventricular nucleus of the hypothalamus stimulates colonic motor activity in fasted rats

The influence of corticotropin releasing factor (CRF) microinjected into the paraventricular nucleus of the hypothalamus (PVN) on colonic motility was investigated in conscious, fasted rats. Rats were chronically implanted with a bilateral guide cannula into the PVN and a catheter into the proximal colon to record motor activity manometrically. Microinjection of CRF (0.6 nmol/rat) into the PVN increased both phasic and tonic motor activity in the proximal colon. Atropine sulfate (1 mg/kg, IP) completely abolished the colonic motor response to CRF. Microinjection of CRF (0.6 nmol/rat) into sites outside of the PVN did not modify colonic motor activity. These data show that CRF acts in the PVN to stimulate tonic and phasic motor activity in the proximal colon. Corticotropin releasing factor action is site specific and mediated through cholinergic pathways.
Effect of certain B vitamin deficiencies on gastric secretion in the rat.

Summary1. The influence of various individual B vitamin deficiencies on gastric secretion has been investigated in the pylorus ligated rat. Pyridoxine deficiency sharply reduced acid secretion. This effect was completely reversed by pyridoxine given only 16 hours before the start of the secretory test. Thiamine deficiency markedly depressed acid secretion. Nicotinic acid deficiency did not depress secretion, while riboflavin and pantothenic acid deficiencies produced only small depressions. 2. Neither aureomycin nor vit. B12 had any effect on gastric secretion when added to the complete basal diet, although each increased weight gain slightly. 3. Pepsin secretion was not markedly depressed in any of the deficiencies studied, with the possible exception of thiamine. Pyridoxine deficiency increased both concentration and total output of pepsin.
Stable automated segmentation of liver MR elastography images for clinical stiffness measurement

Magnetic Resonance Elastography (MRE) is an MRI-based technique that is used for the clinical diagnosis and staging of liver fibrosis by quantitatively measuring the stiffness of the liver. Due to the complexity of the signal characteristics and the presence of artifacts both in the acquired images and in the resulting stiffness images, the selection of the ROI for the stiffness measurement is currently performed manually, which may lead to significant inter- and intrareader variability. An algorithm has been developed to fully automate this analysis for liver MRE images. Automated segmentation of liver MRE images is challenging due to signal inhomogeneity, low contrast, and variability in patient anatomy. An initial liver contour is found by fitting Gaussian peaks to the image histogram and selecting the peak that comprises intensities in the expected range and produces a mask near the expected location of the liver. After correction to reduce intensity inhomogeneity, an active contour based on intensity, with morphology used to implicitly enforce smoothness, is used to segment liver tissue while avoiding blood vessels. The resulting mask is used to initialize another segmentation which splits the region of the elastogram belonging to the liver into homogeneous liver tissue and areas with inclusions, partial volume effects, and artifacts. In a set of 88 cases the algorithm had a -6.0 ± 14.2% stiffness difference from an experienced reader, which was superior to the 6.8 ± 22.8% difference between two readers. The segmentation was run on an additional 200 cases and the final ROIs were subjectively rated by a radiologist. The ROIs in 98% of cases received an average rating of “good” or “acceptable.”
Cooperative activation of action potential Na+ ionophore by neurotoxins

Four neurotoxins that activate the action potential Na+ ionophore of electrically excitable neuroblastoma cells interact with two distinct classes of sites, one specific for the alkaloids veratridine, batrachotoxin, and aconitine, and the second specific for scorpion toxin. Positive heterotropic cooperativity is observed between toxins bound at these two classes of sites. Tetrodotoxin is a noncompetitive inhibitor of activation by each of these toxins (KI = 4-8 nM). These results suggest the existence of three functionally separable components of the action potential Na+ ionophore: two regulatroy components, which bind activating neurotoxins and interact allosterically in controlling the activity of a third ion-transport component, which binds tetrodotoxin.
Trypanosome alternative oxidase: from molecule to function

Trypanosome alternative oxidase (TAO) is the cytochrome-independent terminal oxidase of the mitochondrial electron transport chain. TAO is a diiron protein that transfers electrons from ubiquinol to oxygen, reducing the oxygen to water. The mammalian bloodstream forms of Trypanosoma brucei depend solely on TAO for respiration. The inhibition of TAO by salicylhydroxamic acid (SHAM) or ascofuranone is trypanocidal. TAO is present at a reduced level in the procyclic form of T. brucei, where it is engaged in respiration and is also needed for developmental processes. Alternative oxidases similar to TAO have been found in a wide variety of organisms but not in mammals, thus rendering TAO an important chemotherapeutic target for African trypanosomiasis.
A natural history of "agonist".

This paper constructs a brief history of the biochemical term agonist by exploring the multiple meanings of the root agon in ancient Greek literature and describing how agonist first appeared in the scientific literature of the 20th century in the context of neurophysiologists' debates about the existence and properties of cellular receptors. While the narrow scientific definition of agonist may appear colorless and dead when compared with the web of allusions spun by the ancient Greek agon, the scientific power and creativity of agonist actually resides precisely in its exact, restricted meaning for biomedical researchers.
Commentary on "Inter- and intrareader variability in the interpretation of two radiographic classification systems for juvenile rheumatoid arthritis".

Published online: 2 August 2003 Springer-Verlag 2003 In this issue of Pediatric Radiology there is an interesting article by Doria et al. [1], which discusses the difficulties of using conventional radiographs for the detection and monitoring of arthritic changes in the paediatric skeleton. Inadvertently, the authors have also highlighted the need for further discussion of nomenclature in childhood arthritis. Pediatric Radiology rightly prides itself on having a worldwide readership. Unfortunately, for radiologists with an interest in childhood arthritis who practice on opposite sides of the Atlantic, imaging of the same disease process is hampered by confusion of nomenclature and classification of their patients. In North America the American College of Rheumatology has formulated criteria to describe childhood arthritis under the term ’juvenile rheumatoid arthritis’ (JRA) [2]. The European League Against Rheumatism (EULAR) has alternative criteria which define childhood arthritides in Europe and use the term ’juvenile chronic arthritis’ (JCA) [3]. Importantly, these two classifications have slightly different subgrouping of the arthritides. In particular, JCA includes the spondyloarthropathies, psoriatic arthropathy and those arthropathies associated with inflammatory bowel disease; these subcategories are not included in JRA. In an effort to bring uniformity to the diagnosis, to aid research and to improve management protocols, the Paediatric Standing Committee of the International League of Associations for Rheumatism (ILAR) has tried to establish a new classification [4]. This new classification uses the label ’juvenile idiopathic arthritis’ (JIA). The term JIA indicates onset before 16 years of age of a disease characterised primarily by arthritis, persisting for at least 6 weeks and currently with no known cause. The different subcategories of JIA are systemic onset, polyarticular (rheumatoid factor positive and negative) oligoarthritis, psoriatic, enthesitis and other arthritides. While there still remains some controversy about the term JIA and further work is needed on disease classification, it is hoped this ’new disease’ will bring world-wide uniformity and improve patient management. While interesting to the radiologist, this new classification has not altered our understanding of the primary pathological process in childhood arthritis or the radiological features. In their study, Doria et al. [1] rightly comment that there is significant intraand interobserver variability when using a scoring system based on conventional radiographs. Other recent studies have also shown that conventional radiographs have a limited role in Pediatr Radiol (2003) 33: 671–672 DOI 10.1007/s00247-003-0957-y COMMENTARY
Computerized Tomography On A Logarithmic Polar Grid

AbstractWe consider the problem of reconstructing a function from a finite collection of its lineintegrals. We discretize the function on a logarithmic polar grid. Assuming a special datacollection scheme, we derive a large system of linear equations in the unknown discretizedfunction values. This system has a very nice structure, which is used to decompose it intoa number of reasonably small systems. After regularization, they can be solved using stan-dard direct methods of numerical linear algebra. Results of experiments are shown.1. IntroductionWe consider the problem of reconstructing a two -dimensional function from a finite col-lection of its line integrals. This problem arises in computerized tomography, and manyother areas, see Herman (1980). A well -known approach to its solution is by discretizationof the unknown function on a rectangular grid, see Figure 1. Assuming that the function isconstant inside each picture element (pixel), we obtain a system of linear equations, oneequation per line integral,
Self-rated driving habits among older adults with clinically-defined mild cognitive impairment, clinically-defined dementia, and normal cognition.

Older adults with clinically-defined dementia may report reducing their driving more than cognitively normal controls. However, it is unclear how these groups compare to individuals with clinically-defined mild cognitive impairment (MCI) in terms of driving behaviors. The current study investigated self-reported driving habits among adults age 60 and older with clinical MCI (n = 41), clinical mild dementia (n = 40), and normal cognition (n = 43). Participants reported their driving status, driving frequency (days per week), and how often they avoided accessing the community, making left turns, driving at night, driving in unfamiliar areas, driving on high-traffic roads, and driving in bad weather. After adjusting for education, a MANCOVA revealed that participants with MCI and dementia avoided unfamiliar areas and high-traffic roads significantly more than normal participants. Participants with dementia also avoided left turns and accessing the community more than those with normal cognition and MCI (p < 0.05 for all). The other driving variables did not significantly differ between groups. Thus, older adults with clinically-defined MCI, as well as those with dementia, avoided some complex driving situations more than cognitively intact adults. However, all diagnostic groups had similar rates of driving cessation and frequency. Future research should examine the safety implications of such findings.
Clinical and radiographic results of endoscopic injection for vesicoureteral reflux: defining measures of success.

Abstract Objective Criteria for success following endoscopic vesicoureteral reflux (VUR) surgery vary greatly. We sought to define outcomes based on radiographic and long-term clinical follow up. Methods We reviewed the charts and interviewed parents of children who underwent endoscopic treatment for primary VUR (grades I-IV). All patients had a postoperative voiding cystourethrogram (VCUG) at mean of 3 months (1–21 months) and all cases of postoperative febrile urinary tract infection (FUTI) prompted repeat VCUG. Radiographic success was defined as no VUR on postoperative VCUG and clinical success as no FUTIs during follow up of 12–36 months. To demonstrate how criteria for success can affect outcomes, we calculated the success rates using different definitions. Results In 2004–2008, 336 patients (296 female and 40 male, mean age 4 years) were treated with dextranomer/hyaluronic acid via the Double-HIT method. Initial radiographic success was 90% (302/336). Of these, 19 (6%) developed FUTIs, 12 (4%) of whom had recurrent VUR, and 5 (2%) went on to open surgery. Of the radiographic failures, 18% were observed with no further treatment. Success defined clinically was 94% (281/300), and as ‘radiographic cure and no clinical evidence of FUTIs’ it was 82% (275/336). Conclusions It is important to agree on a universal definition of success for VUR interventions to compare across studies and across therapies. Clinical success is more meaningful to the patient, and initial radiographic success could be followed by UTI necessitating further intervention. We question the need for routine postoperative VCUG.
Signaling by Transmembrane Proteins Shifts Gears

The HAMP domain is present in a large number of transmembrane proteins in prokaryotes including histidine kinases, adenylyl cyclases, chemotaxis receptors, and phosphatases. In this issue of Cell, Hulko et al. (2006) report the NMR structure of a HAMP domain and present data suggesting that it transduces signals through a simple rotation of its four-helix parallel coiled coil.
Improving Compliance with Work Zone Speed Limits Effectiveness of Selected Devices

Thousands of crashes occurring in work zones each year lead to numerous fatalities and injuries. The sizeable portion of these crashes attributed to excessive speed emphasizes the need to motivate drivers to comply with speed limits in work zones. A recent research project was conducted to determine effective measures to motivate and encourage drivers to observe posted speed limits in work zones. Three devices were tested in that project: a speed display trailer, changeable message sign with radar, and orange-border speed limit sign. Results from field testing indicate that devices with the ability to display drivers' speeds have considerable potential for reducing speeds and improving compliance. Orange borders greatly improve the visibility and conspicuity of speed limit signs, but they do not have a consistent measurable effect on compliance. In the absence of active enforcement, data from this project indicate that drivers are likely to drive as fast as they feel comfortable, regardless of the posted ...
Evolution of the donor T-cell repertoire in recipients in the second decade after allogeneic stem cell transplantation

After allogeneic stem cell transplantation (SCT), T lymphocyte function is reestablished from the donor's postthymic T cells and through thymic T-cell neogenesis. The immune repertoire and its relation to that of the donor have not been characterized in detail in long-term adult SCT survivors. We studied 21 healthy patients in their second decade after a myeloablative SCT for hematologic malignancy (median follow-up, 12 years). Immune profiles were compared with donor samples cryopreserved at transplant and beyond 10 years from SCT. Only one recipient was on continuing immunosuppression. Compared with the donor at transplant, there was no significant difference in CD4, CD8, natural killer, and B-cell blood counts. However, compared with donors, recipients had significantly fewer naive T cells, lower T-cell receptor excision circle levels, fewer CD4 central memory cells, more effector CD8(+) cells, and more regulatory T cells. TCR repertoire analysis showed no significant difference in complexity of TCRVβ spectratype between recipients and donors, although spectratype profiles had diverged with both gain and loss of donor repertoire peaks in the recipient. In conclusion, long-term allogeneic SCT survivors have subtle defects in their immune profile consistent with defective thymic function but compatible with normal health. This study is registered at http://www.clinicaltrials.gov as NCT00106925.
What is the ‘Cause’ in Causal Decision Theory?

A simple counterfactual theory of causation fails because of problems with cases of preemption. This might lead us to expect that preemption will raise problems for counterfactual theories of other concepts that have a causal dimension. Indeed, examples are easy to find. But there is one case where we do not find this. Several versions of causal decision theory are formulated using counterfactuals. This might lead us to expect that these theories will yield the wrong recommendations in cases of preemption. But they do not. The explanation, I argue, is that the ‘cause’ that has been the target of counterfactual analyses is a specific relation, ‘actual causation’, that is not needed for prospective deliberation. A simple counterfactual theory of causation seems to capture the notion of cause needed for causal decision theory. This shows, in opposition to some critics, that counterfactual theories of causation are not barking up the wrong tree.
MacMahon's Partition Analysis: II Fundamental Theorems

We continue the study of the method outlined by MacMahon in Section VIII of [10]. The long range object is to show the relevance of MacMahon's ideas in current partition-theoretic research. In this paper we present a number of theorems which MacMahon overlooked. For example, the number of partitions of n with non-negative first and second differences between parts equals the number of partitions of n into triangular numbers.
Cycle-Time Reduction in Machining by Recursive Constraint Bounding

Modeling uncertainty in machining, caused by modeling inaccuracy, noise and process time-variability due to tool wear, hinders application of traditional optimization to minimize cost or production time. Process time-variability can be overcome by adaptive control optimization (ACO) to improve machine settings in reference to process feedback so as to satisfy constraints associated with part quality and machine capability. However, ACO systems rely on process models to define the optimal conditions, so they are still affected by modeling inaccuracy and noise. This paper presents the method of Recursive Constraint Bounding (RCB2) which is designed to cope with modeling uncertainty as well as process time-variability. RCB2 uses a model, similar to other ACO methods. However, it considers confidence levels and noise buffers to account for degrees of inaccuracy and randomness associated with each modeled constraint. RCB 2 assesses optimality by measuring the slack in individual constraints after each part is completed (cycle), and then redefines the constraints to yield more aggressive machine settings for the next cycle. The application of RCB 2 is demonstrated here in reducing cycle-time for internal cylindrical plunge grinding.
The effect of donor‐acceptor complexes on the stereochemistry of alternating copolymers of alkyl vinyl ethers with maleonitrile and fumaronitrile

This paper presents the results of a study of the alternating copolymerization of alkyl vinyl ethers, as electron-donors (D), with maleonitrile and fumaronitrile, respectively, as electronacceptors (A), and a 13C NMR evaluation of the stereochemistry of the copolymers. The results show that the two copolymers are stereochemically different. By use of model compounds as well as UV studies and quantum chemical (PVCILO) calculations, attempts to correlate the relationship of the complex (C) to copolymer structure have been made. We have previously reported studies on copolymerization of alkyl vinyl ethers and N-substituted maleimides. Stereochemical consequences resulting from variation of five parameters, each of which according to Mulliken theory should vary the concentration of C relative to that of the free monomers, in every case, were that the cis-trans ratio of the succinimide unit of the copolymer chain varied in accord with theory, being higher at higher [C].
Suppression of corneal epithelial choline acetyltransferase activity by lid closure

Abstract Unilateral lid closure lowered corneal epithelial choline acetyltransferase activity in eyes that grossly and histologically appeared normal. This effect on choline acetyltransferase activity was relatively specific and not the result of a generalized depression of metabolism since thymidine, uridine, leucine, and alanine incorporation rates into corneal epithelium were not significantly altered. Lactic dehydrogenase activity was not depressed. Decreased choline acetyltransferase activity was present 24 hr after lid closure and was maximum by the eighth day of lid closure. Recovery of enzyme activity after re-opening the lids required more than four weeks.
Ermittlung molekularkinetischer Daten aus Keimbildungsuntersuchungen. Keimbildung von PbS auf NaCl und NaF im UHV

Es wird untersucht, inwieweit Vorstellungen uber das Kondensationsverhalten von Atomen auf das Kondensationsverhalten von Molekulen ubertragbar sind. Dazu wird das System PbS/NaCl und PbS/NaF mit dem System Edelmetalle/NaCl verglichen. Als charakteristische Grose wird die Grenzkeimdichte N8 herangezogen, die gemas Modellvorstellungen eine Funktion der molekularkinetischen Grosen Adsorptionsenergie Qad, Diffusionsenergie Qd, Schwingungsfrequenz v0 und der Kondensationsparameter Substrattemperatur T und Bedampfungsrate N ist. Im Bereich von 100 bis 315°C und bei einer Bedampfungsrate von 2,7 × 1013 cm−2 × s−1 zeigt die Grenzkeimdichte etwa die nach dem Modell zu erwartende Temperaturbhangigkeit. Zwischen den Systemen PbS/NaCl und PbS/NaF konnten keine Unterschiede in der Grenzkeimdichte festgestellt werden. Folgende Werte wurden ermittelt: Qad ≈ 0,54 eV; Qd ≈ 0,22 eV; v0 ≈ 108 s−1. Qad und Qd unterscheiden sich nur wenig von den Werten fur Au und Ag auf NaCl. Jedoch ist v0 um 4 Grosenordnungen kleiner als der fur das System Edelmetalle/Alkalihalogenide als gultig angenommene Wert von ≈ 1012 s−1. A simple model of saturation density of nuclei Ns is discussed. In this model Ns is a function of adsorption energy Qad, activation energy for surface diffusion Qd, vibrational frequency v0 associated with evaporation and migration of single deposit atoms (molecules), and the condensation conditions substrate temperature T and incidence rate N of deposit atoms (molecules). The proposed temperature dependence of Ns could be verified experimentally in the systems PbS/NaCl and PbS/NaF for the temperature region from 100 to 315°C and an incidence rate N = 2,7 × 1013 cm−2 s−1. There was no difference for Ns in both systems. The following values were determined: Qad ≈ 0,54 eV, Qd ≈ 0,22 eV and v0 ≈ 108 s−1.
ViDi-O (View-It and Do-It Online): An Approach to Internet Commerce in a Higher Education Setting.

THROUGHOUT THE 1990’s, higher education—struggling with an outdated management paradigm—has been buffeted by the latest fashions in management thinking. Thus, as the competition for students has increased, colleges and universities have turned to the so-called “quality movement” for better ways to focus on and satisfy the requirements of those they serve. Faced with flat revenues but spiraling costs, some of these same institutions have also resorted to business process reengineering and other more radical management techniques, seeking to do more and better with fewer resources. Still other market forces have contributed to this period of self-assessment and adaptation within higher education. Most importantly, the advent of client/server computing, Internet and Intranet commerce, and the need to replace legacy computer systems before the debacle of “the year 2000,” have encouraged colleges and universities to revisit their information technology (I/T) strategies and to make heavy infrastructural investments for the future.
Among the Troops: Seeing the Iraq War Through Three Journalistic Vantage Points

During Operation Iraqi Freedom, the Pentagon introduced a program "embedding" journalists in military units. Embedded reporters have been widely criticized for allegedly failing to adequately cover effects of the war on Iraqi civilians, while over-emphasizing the personal lives of troops. Proponents of the embedding program argue that the program provides journalists with a detailed understanding of military culture and life on the frontline. In addition to the embedded reporters, some journalists were stationed in Baghdad and others were independent and free to roam. I argue that these three journalistic vantage points channeled reporters toward particular news content, while limiting their access to others. I hypothesize that while embedded reporters effectively presented the military experience of the war and the Baghdad-stationed reporters successfully covered the Iraqi experience of the war, the independent reporters were able to provide the most balanced coverage of the war. I demonstrate that despite the largely one-sided story presented, articles by embedded journalists were both more prominent and more widely available than coverage from other vantage points. Due to the dominance of embedded reporting, I conclude by noting that the majority of war coverage in print media heavily emphasized the soldier's experience of the war, while downplaying the effects of the invasion on the Iraqi people. By conducting a content analysis of 742 print news articles by 156 journalists from the major combat period of the war, this study offers one of the first systematic documentations of the substantive content of Iraq war coverage.
Structure of a B‐form DNA/RNA chimera (dC)(rG)d(ATCG) complexed with daunomycin at 1.5 Å resolution

The crystal structure of a DNA/RNA chimera (dC)(rG)d(ATCG) complexed with the anticancer drug daunomycin has been determined at 1.5 A resolution with Rwork and Rfree of 19.7 and 23.3%, respectively, for 2767 reflections. The complex crystallizes in space group P41212, with unit-cell parameters a = b = 28.05, c = 53.16 A, and contains one nucleic acid strand and one daunomycin molecule in the asymmetric unit. To our knowledge, this is the first crystal structure of a DNA/RNA chimera complexed with an intercalating drug. The DNA/RNA chimera adopts the B-form helical conformation, with the 2′-hydroxyl group in the major groove of the duplex, forming hydrogen bonds to N7 and the anionic phosphate oxygen of its 3′-side adenine. The present results indicate that the replacement by the ribose sugar in the DNA sequence does not change the geometry and intercalation pattern of daunomycin. A model of B-form RNA has been built based on the present structure. The model indicates that the interactions of the 2′-hydroxyl groups in the B-form duplex depend on their 3′-side nucleotides.
Substance Use Among Native American Indian Youth: A Selected Review of Causality

The author presents a selected review of substance use causality among Native American Indian youth. A review of selected empirical research relative to substance use is given. In addition, selected examples of research-oriented implications and practical suggestions are offered.
Bounding parameters in a linear regression model with a mismeasured regressor using additional information

This paper discusses a linear regression model with a mismeasured regressor in which the measurement error is correlated with both the latent variable and the regression error. We use a linear structure to capture the correlation between the measurement error and the latent variable. This paper shows that the variance of the latent variable is very useful for revealing information on the parameters which otherwise cannot be obtained with such a nonclassical measurement error. The main result is that the finite bounds on the parameters can be found using the variance of the latent variable, regardless of how severely the measurement error and the regression error are correlated, if the mismeasured regressor contains enough information on the latent one. This paper also discusses the special but interesting case of the latent variable being dichotomous. In this case, the mean of the latent variable may even reveal information on the correlation between the measurement error and the regression error. All the bounds developed in the paper are tight.
Efficient Algorithms and Policies for Demand Response Scheduling

AbstractThe authors consider efficient mechanisms to optimize the power consumption within a home, industrial facility, college campus, or other facility or set of facilities. The system is controlled centrally by an energy management controller (EMC), which determines the timing of the operation of some of the devices within the facilities. The authors introduce an approximate dynamic programming (ADP) algorithm for this problem and show that the ADP outperforms a recent dynamic programming (DP) algorithm. However, even the ADP fails to solve sufficiently quickly when applied to larger instances. Therefore, the authors also propose several heuristic scheduling policies that provide accurate solutions in a fraction of the time required by the ADP. The authors discuss the computational performance of the ADP algorithm and scheduling policies, and insights gained from the models.
From Demonization of the Masses to Democratic Practice in the Work of Nietzsche, Heidegger, and Foucault

This paper argues that the dichotomy between individuals, as bearers of unique and freely chosen identities, and the masses, as the large numbers of others who are conforming and uncritical, should be understood as a constructed dichotomy. This dichotomy is both supported and dismantled in the works of Friedrich Nietzsche, Martin Heidegger, and Michel Foucault. Each of these thinkers reinforced the idea that there exist conforming and threatening masses from which individuals should separate themselves. And yet by theorizing the limitations and contextual nature of individual identity, they have also provided the foundations for revealing the dichotomy as illusory as well as problematic for reasoned thought and politics. The significance of this argument is that the fear of sameness and conformity within modern mass society creates a serious obstacle to broad based and democratic political engagement among people.
Modified heparin-bonded catheter for cannulation of the coronary sinus from the femoral vein.

Serial sampling from the coronary sinus is an attractive technique for drawing blood samples to be used in the characterization of procoagulant activity during coronary interventions. We have developed a modified Simmons catheter for rapid cannulation of the coronary sinus from the femoral approach. The catheter design incorporates heparin bonding and distal side-holes to minimize blood sampling artifacts. Coronary sinus cannulation was performed via the femoral approach in 186 patients by use of a multipurpose catheter (n = 8), an unmodified Simmons I or II catheter (n = 64), or the modified Simmons catheter (n = 114). The coronary sinus was cannulated successfully with the modified Simmons catheter in 97% of patients; the success rate with the unmodified Simmons II catheter was 87% (P = 0.02). The modified Simmons catheter represents an improved technique for cannulation of the coronary sinus from the femoral vein. © Wiley-Liss, Inc.
Synchronization characteristics of paroxysmal EEG activity.

Abstract 1. 1. Direct superimposition of highly resolved potential contours was capable of only first order measurements. 2. 2. Cross-correlations of contemporaneous potentials were made in an attempt to achieve a higher order of precision measurement. 3. 3. Using both types of measurement it was shown that physiological cortical visual system activities, in both man and cat, were closely synchronized following retinal stimulation. 4. 4. Convulsive discharges, even when primarily involving the visual system in man, showed a marked variability in the time of occurrence of measurable elements of the potential discharge derived from homologous regions of the head. 5. 5. These latter measurements suggested that the convulsive discharge was a contingent, adventitious action superimposed on the passive electrical characteristics of the anatomical network.
Structural evolution during ice-sphere sintering

Two-dimensional ice-sphere arrays were produced in a cold room and studied as a geometrically simplified model of dry snow aggregates. The structural evolution of the ice-sphere arrays under either a quasi-isothermal condition or a temperature gradient was examined temporally. Two observational techniques were combined for the structural characterization. Optical microscopy was used to perform periodic observations, whereas scanning electron microscopy was used to both acquire high-resolution images and confirm the hexagonal crystal structure. Different thermal conditions led to the development of different morphologies of necks between two ice spheres by affecting the water vapour transfer in the pore spaces and the sublimation–condensation of water molecules. The microstructure of necks could also play a significant role in the structure development at later times by inducing or enhancing the local temperature gradient. This feature was discussed on the basis of steady-state heat transfer modelling of a two-sphere structure. Copyright © 2010 John Wiley & Sons, Ltd.
Does activation of a script facilitate lexical access

Abstract According to script-based accounts of text processing (e.g., Walker & Yekovich, 1987 ), activation of a script during reading can facilitate lower level processes, such as lexical access, in a top-down fashion. A competing perspective, known as modularity theory Fodor 1983 suggests that low-level processes, such as lexical access, can become informationally encapsulated and thus are not influenced by script activation. In two experiments, passages were read off of a computer screen. For each of four passages six words were identified as either central or peripheral to the script. Versions of each passage were constructed in which these same six words were not related to the script. Thus, these words appeared in both scripted and nonscripted versions of each story. The efficiency of lexical access was measured in two ways: by either word reading time or naming latency. The data, collected within subjects, provide little evidence of script-related facilitation of lexical access, thus supporting modularity theory.
Analysis of the early spectra and light curve of SN 1987A

Numerical modeling of supernova spectra, light curves, and hydrodynamics requires physical inputs, numerical techniques, approximations, and assumptions which must be thoroughly understood in order to study the details of supernova explosions. Here, we discuss some of these in the context of the early evolution of supernova 1987A. Gray radiation-hydrodynamics is used to calculate the bolometric light curve and the hydrodynamic evolution of the supernova. Synthetic spectra are then obtained for the resulting density and velocity structure. The spectrum calculations are performed using a special-relativistic treatment of the radiative transfer equation in the comoving frame, line blanketing by about 10(exp 5) spectral lines, and departures from local thermodynamic equilibrium (LTE) for H I, He I, Mg II, and Ca II. We find that we are able to simultaneously fit the early light curve and spectra reasonably well, using a progenitor model from Arnett (1991a), without fine-tuning the free parameters. Temperature structures and radiative equilibrium, non-LTE effects, homologous expansion, and mean opacities are discussed.
2,3-Dihydro-2,3-dihydroxy-aflatoxin B1: an acid hydrolysis product of an RNA-aflatoxin B1 adduct formed by hamster and rat liver microsomes in vitro.

Abstract Fortified hamster and rat liver microsomes bind the carcinogen aflatoxin B1 (AFB1), but not its much less carcinogenic 2,3-dihydro derivative (aflatoxin B2), to RNA in vitro . Mild acid hydrolysis of the RNA-AFB1 adduct yields a product indistinguishable from synthetic 2,3-dihydro-2,3-dihydroxy-AFB1 in (a) its UV absorption spectra in neutral and alkaline solution, (b) its thin layer chromatography in several solvent systems, and (c) the mass spectra of the acetonide and diacetyl derivatives. AFB1-2,3-oxide is the probable reactive precursor of the RNA-AFB1 adduct. This epoxide merits consideration as a candidate ultimate carcinogenic metabolite of AFB1.
Foliage and Litter Chemistry, Decomposition, and Nutrient Release in Pinus taeda

Following fertilization of forest plantations, high accumulations of nutrients in the forest floor creates the need to assess rates of forest floor decomposition and nutrient release. The study site was a 25-year old experimental loblolly pine plantation in the North Carolina Sandhills Region. Soluble and insoluble N, P, carbohydrate and phenol-tannin fractions were determined in foliage and litter by extraction with trichloroacetic acid. The long-term forest floor decomposition rate and decomposition and nutrient release in an experiment simulating removal of the overstory canopy were also determined. In litter, insoluble protein-N comprised 80%–90% of total-N concentration while soluble inorganic- and organic-P comprised 50%–75% of total-P concentration explaining forest floor N accumulations. Fertilization did not increase soluble carbohydrates in litter and forest floor decomposition rates. Loblolly pine forest floor decomposing in environmental conditions simulating removal of the overstory canopy was greatly accelerated and indicated 75% mass loss and release of 80% of the N pool within one year. This could result in a loss of substantial quantities of N at harvest due to low N uptake by seedlings in the newly planted next rotation suggesting management of the forest floor at harvest is essential to conserve site N capital in these N limited systems.
Rodríguez-Iturbe Receives 2009 William Bowie Medal

Ignacio Rodrguez-Iturbe was awarded the 2009 William Bowie Medal at the AGU Fall Meeting Honors Ceremony, held on 16 December 2009 in San Francisco, Calif. The medal is for “outstanding contributions to fundamental geophysics and for unselfish cooperation in research.”