cssi/SciSciGPT-SciSciNet huggingface dataset:
More on time series designs: A reanalysis of mayer and Kozlow's data

A recent article by Mayer and Kozlow introduces a time series experiment to science education researchers. This article examines in greater detail design considerations and reanalyzes their data using time series analysis. The first applications of time series experimental methodology to science education research were reported by Mayer and Lewis (1979) and by Mayer and Kozlow (1980). This article discusses Mayer and Kozlow's work and presents a reanalysis of their data which is intended to be heuristic, not critical. (All data were supplied by Dr. Mayer and permission was granted to use the data.) Both design and analysis will be examined. It is important to distinguish time series experimental design from time series analysis. The former, as presented by Campbell and Stanley (1966) and detailed by Glass, Willson, and Gottman (1975), is concerned with structuring treatment conditions and observations over time to make causal inferences. Time series analysis is a set of statistical techniques from which an appropriate technique can be selected to analyze collected data in the framework of a time series design. Just as data from in a randomized experiment might be analyzed using a one-way analysis of variance or a Kruskal- Wallis H-test, data from a time series design may be subjected to several alternative analysis techniques.
8-Isoprostaglandin E2 Enhances Receptor-activated NFκB Ligand (RANKL)-dependent Osteoclastic Potential of Marrow Hematopoietic Precursors via the cAMP Pathway

Lipid oxidation products promote atherosclerosis and may also affect osteoporosis. We showed previously that oxidized lipids including 8-isoprostaglandin E2 (isoPGE2) inhibit osteoblastic differentiation of preosteoblasts. Since osteoporosis is mediated both by decreased osteoblastic bone formation and by increased osteoclastic bone resorption, we assessed whether oxidized lipids regulate the osteoclastic potential of marrow hematopoietic cells. Treatment of marrow-derived preosteoclasts with isoPGE2 enhanced osteoclastic differentiation as evidenced by increased tartrate-resistant acid phosphatase (TRAP) activity and multinucleation, which were inhibited by calcitonin, and increased numbers of resorption pits. The enhanced osteoclastic differentiation by isoPGE2 was observed whether preosteoclasts were in coculture with stromal cells or in monoculture in the presence of receptor-activated NFκB ligand (RANKL) and macrophage colony-stimulating factor. Receptor antagonist studies suggest that isoPGE2 effects were mediated by prostaglandin receptor subtypes EP2/DP on preosteoclasts and subtype EP1 and thromboxane receptors on stromal/osteoblast cells. The enhanced TRAP activity was also inhibited by cAMP-dependent protein kinase inhibitors, and isoPGE2 elevated intracellular cAMP levels of preosteoclast monocultures. Other oxidized lipids also enhanced the TRAP activity of preosteoclast monocultures. These data suggest that isoPGE2 enhances osteoclastic differentiation of marrow preosteoclasts and that this regulation occurs via the cAMP-dependent protein kinase pathway.
Transient Left Ventricular Apical Ballooning After Cocaine Use: Is Catecholamine Cardiotoxicity the Pathologic Link?

We describe a patient who developed acute chest pain after using cocaine and had ST-segment elevation in the anterior leads on electrocardiography with mild elevation of cardiac enzymes. Cardiac catheterization showed normal coronary arteries with no coronary vasospasm. Left ventricular angiography revealed typical ballooning of the left ventricular apex during systole with an estimated left ventricular ejection fraction of 25%. The symptoms improved during the next few hours, and follow-up echocardiography 4 days later showed complete resolution of the left ventricular dysfunction. Transient left ventricular apical ballooning (LVAB) was diagnosed. To our knowledge, LVAB (also known as Takotsubo cardiomyopathy or "broken heart syndrome") has not been reported previously in association with cocaine use. We discuss the possible pathophysiologic link between LVAB and cocaine-induced cardiotoxicity.
Chlamydia Trachomatis Secretion of Proteases for Manipulating Host Signaling Pathways

The human pathogen Chlamydia trachomatis secretes numerous effectors into host cells in order to successfully establish and complete the intracellular growth cycle. Three C. trachomatis proteases [chlamydial proteasome/protease-like activity factor (CPAF), tail-specific protease (Tsp), and chlamydial high temperature requirement protein A (cHtrA)] have been localized in the cytosol of the infected cells either by direct immunofluorescence visualization or functional implication. Both CPAF and Tsp have been found to play important roles in C. trachomatis interactions with host cells although the cellular targets of cHtrA have not been identified. All three proteases contain a putative N-terminal signal sequence, suggesting that they may be secreted via a sec-dependent pathway. However, these proteases are also found in chlamydial organism-free vesicles in the lumen of the chlamydial inclusions before they are secreted into host cell cytosol, suggesting that these proteases may first be translocated into the periplasmic region via a sec-dependent pathway and then exported outside of the organisms via an outer membrane vesicles (OMVs) budding mechanism. The vesiculized proteases in the inclusion lumen can finally enter host cell cytosol via vesicle fusing with or passing through the inclusion membrane. Continuing identification and characterization of the C. trachomatis-secreted proteins (CtSPs) will not only promote our understanding of C. trachomatis pathogenic mechanisms but also allow us to gain novel insights into the OMV pathway, a well-known mechanism used by bacteria to export virulence factors although its mechanism remains elusive.
Surface Area Loss of Supported Platinum in Polymer Electrolyte Fuel Cells

Life tests of polymer-electrolyte fuel cells using supported Pt catalyst in thin film catalyst layers are run for up to 4,000 h at maximum power. Particle ripening is readily evident using these types of electrodes in which the high catalyst utilization efficiency apparently subjects in majority of the platinum to conditions that sustain particle growth. X-ray diffraction analyses indicate that the initial platinum specific surface areas of 100 m[sup 2]/g Pt eventually stabilize to about 40 to 50 m[sup 2]/g in the cathode and 60 to 70 m[sup 2]/g in the anode. Interestingly, this loss in surface area does not affect the apparent catalytic activity of these fuel cell electrodes. A crystallite migration particle growth mechanism is suggested by the shape of the particle size distribution curves. Since the presence of liquids is known to lower the activation energy for particle growth, the particle size difference between the two electrodes may possibly be attributed to the different hydration levels at the anode and the cathode in operating polymer electrolyte fuel cells.
Steady-State Interactions of Glibenclamide with CFTR: Evidence for Multiple Sites in the Pore

The objective of the present study was to clarify the mechanism by which the sulfonylurea drug, glibenclamide, inhibits single CFTR channels in excised patches from Xenopus oocytes. Glibenclamide blocks the open pore of the channel via binding at multiple sites with varying kinetics. In the absence of glibenclamide, open-channel bursts exhibited a flickery intraburst closed state (C1); this is due to block of the pore by the pH buffer, TES. Application of 25 μM glibenclamide to the cytoplasmic solution resulted in the appearance of two drug-induced intraburst closed states (C2, C3) of widely different duration, which differed in pH-dependence. The kinetics of interaction with the C3 state, but not the C2 state, were strongly voltage-dependent. The durations of both the C2 and C3 states were concentration-dependent, indicating a non-linear reaction scheme. Application of drug also increased the burst duration, which is consistent with an open-channel blocking mechanism. A kinetic model is proposed. These results indicate that glibenclamide interacts with open CFTR channels in a complex manner, involving interactions with multiple binding sites in the channel pore.
EMG Biofeedback as Treatment for Patellofemoral Pain Syndrome

Patellofemoral pain syndrome may be classified as a dysfunction of the patella's ability to track in the femoral groove. This study identifies an effective treatment approach for patellofemoral pain syndrome. The approach integrates the concept of improved patellar tracking through selective enhancement of the vastus medialis oblique muscle with conventional exercise regimens for patellofemoral pain syndrome. Six patellofemoral pain syndrome patients were enrolled in a three-phase electromyographic biofeedback and exercise program: 1) biofeedback orientation and instruction in isometric quadriceps contractions, straight leg raises, and a home program; 2) biofeedback training for vastus medialis oblique enhancement with isometric quadriceps contractions, straight leg raises, terminal knee extensions, and progressive resistive exercises; and 3) incorporation of increased vastus medialis oblique activity in functional patterns of movement. All six patients learned to alter their vastus medialis oblique activity through the use of this treatment approach. The alteration of vastus medialis oblique activity resulted in an apparent change in the patellofemoral forces and a concomitant decrease in the patients' complaints of pain. These patients were able to return to pain-free functional activities in only six to nine treatment sessions within a 4- to 6-week period. The use of electromyographic biofeedback coupled with a graded exercise program is an efficient and effective treatment approach for patellofemoral pain syndrome patients.J Orthop Sports Phys Ther 1984;6(2):95-103.
Polychlorinated Biphenyl: Interaction with Duck Hepatitis Virus

Ten-day-old mallard ducklings fed a polychlorinated biphenyl at concentrations of 25, 50, and 100 parts per million for 10 days suffered no apparent clinical intoxication. Five days later these birds were challenged with duck hepatitis virus, and they suffered significantly higher mortality than birds which were not exposed to the polychlorinated biphenyl.
The effect of perceived role requirements on reactions to favor-doing

Abstract The hypothesis of the present study was that when performing favors is in accord with role requirements attraction will be greater than when it is not, and that when withholding favors is in accord with role requirements, attraction will be greater than when it is not. To test this hypothesis, an experiment examined the effects on attraction to another person of one magnitude of favor (sharing of money), committed or omitted, and in accord, or not, with perceived role requirements (cooperation or competition). Pairs of subjects participated in a word game, under either a cooperative or competitive set. Each subject perceived that his partner won most of the money. Partners then either shared or did not share their winnings with the subject. In general, it was found that appropriate favors and nonfavors resulted in greater attraction than did inappropriate favors and nonfavors. Thus, partners who shared in the cooperation condition and who did not share in the competition condition were liked better than were partners who did not share in the cooperation condition and who did share in the competition condition.
Including Side Chain Flexibility in Continuum Electrostatic Calculations of Protein Titration

We have extended Monte Carlo procedures for computing statistical averages over protonation states of a protein to include conformational states of the titrating amino acid side chains. This comput...
An NADP/thioredoxin system in leaves : purification and characterization of NADP-thioredoxin reductase and thioredoxin h from spinach

Abstract An NADP/thioredoxin system, consisting of NADPH, NADP-thioredoxin reductase (NTR), and its thioredoxin, thioredoxin h, has been previously described for heterotrophic plant tissues, i.e., wheat seeds and cultured carrot cells. Until now there was no evidence for this system in green leaves. Here, we report the identification of protein components of the NADP/thioredoxin system in leaves of several species. Thioredoxin h and NTR, which were both recovered in the extrachloroplastic fraction, were purified to apparent homogeneity from spinach leaves. This represents the first time that NTR has been characterized from a plant source. Similar to that from bacterial and mammalian sources, spinach leaf NTR was a flavoprotein (Mr 68,000) composed of two subunits of identical molecular mass (Mr 33,000) that resembled Escherichia coli NTR immunologically. Spinach thioredoxin h existed in two forms (Mr, of 13,500 and 12,000) and was highly specific for plant NTR. Thioredoxin h and NTR partially purified from spinach roots showed properties similar to their counterparts from leaves. Spinach cytosolic thioredoxin h differed from chloroplast thioredoxin m or f from the same source but was similar to thioredoxin h from wheat seed in immunological properties.
On the regulation of DNA transcription

A system of gene regulation has been proposed based upon the concept that any given DNA is transcribed along only one strand (the “up” strand) and that the function of the unread (or “down”) strand is to break the hydrogen bonds holding the RNA product through reformation of the original hydrogen bonds of the DNA. A second DNA, whose RNA product is complementary to the down strand of the first DNA, acts as a genetic regulator, since its RNA can inhibit the release of messengers from the first DNA by combining with the down strand and blocking its displacement function. These relationships fit the genetic description of the operator and regulator genes of Jacob, Perrin, Sanchez & Monod (1960) . Further consideration of the system suggests that the operator gene also produces an RNA inhibitory to the regulator DNA. The ability of small molecules (inducers and repressors) to modify rates of enzyme production is explained by their ability to react with and inactivate the “censor” RNA produced by the regulator gene, and the “messenger” RNA of the operator gene. These reactions are catalysed by enzymes whose templates are the same RNA molecules which act as their substrates. Several factors relating to the operation and origin of these mechanisms are discussed and some experimental predictions are described.
Three-dimensional modeling of lung morphogenesis using fractals

The bronchial tree is one of the most well known fractal structure in the human body. Fractal objects like the bronchial tree have complex structures with self-similar properties over different scales. The fractal structure of the bronchial tree is imposed by optimization of resource utilization requirements in the lung, such as efficient distribution of blood and air. Thus, the morphology of the lung is directly related to its function and changes in its structure can be linked to disfunction. Since the bronchial tree is a fractal structure, its fractal dimension can be used as a tool for the detection of structure changes and quantification of lung disease. In this paper, we present an algorithm for the construction of a 3-D bronchial tree model based on fractal growth rules and actual morphometric data. The 3-D fractal dimension of the model is computed and subsequently compared with the 3-D fractal dimension of a bronchial tree segmented from normal actual lung data.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
A word-ordering test to differentiate between aphasia and schizophrenia

The capacity of a word-ordering task to differentiate aphasic and schizophrenic patients was assessed. Cards containing words from 10 types of sentences were given to the patients. Each sentence was presented individually with the words in jumbled order and patients were asked to reorder them to produce a gramatically correct sentence. Process and reactive schizophrenics were differentiated from aphasic patients using the dual criteria of more than three incorrect sentences or an average of more than 90 sec per sentence as indicative of aphasia. These criteria were initially tested on a group of aphasics matched with the schizophrenics on age and education and cross-validated using a second more representative sample (unmatched) of aphasics. Both comparisons showed no errors of classification. Further analyses indicated no need for separate norms or classification criteria related to the sex, age, or educational level of the patients.
Effect of diabetes fatalism on medication adherence and self-care behaviors in adults with diabetes

Abstract Objective Diabetes fatalism is defined as "a complex psychological cycle characterized by perceptions of despair, hopelessness, and powerlessness" and associated with poor glycemic control. This study examined the association between diabetes fatalism and medication adherence and self-care behaviors in adults with diabetes. Methods Data on 378 subjects with type 2 diabetes recruited from two primary care clinics in the Southeastern United States were examined. Previously validated scales were used to measure diabetes fatalism, medication adherence, diabetes knowledge and diabetes self-care behaviors (diet, physical activity, blood sugar testing and foot care). Multiple linear regression was used to assess the independent effect of diabetes fatalism on medication adherence and self-care behaviors controlling for relevant covariates. Results Fatalism correlated significantly with medication adherence ( r =0.24, P r =−0.26, P r =−0.20, P r =−0.19, P β =0.029, 95% confidence interval (CI) 0.016, 0.043], diabetes knowledge ( β =−0.042, 95% CI −0.001, −0.084), diet ( β =−0.063, 95% CI −0.039, −0.087), exercise ( β =−0.055, 95% CI −0.028, −0.083) and blood sugar testing ( β =−0.055, 95% CI −0.023, −0.087). There was no significant association between diabetes fatalism and foot care ( β =−0.018, 95% CI −0.047, 0.011). The association between diabetes fatalism and medication adherence, diabetes knowledge and diabetes self-care behaviors did not change significantly when depression was added to the models, suggesting that the associations are independent of depression. Conclusion Diabetes fatalism is associated with poor medication adherence and self-care and may be an important target for education and skills interventions in diabetes care. In addition, the effect of diabetes fatalism is independent of depression, suggesting that interventions that target depression may not be sufficient to deal with diabetes fatalism.
A counterfort versus a cantilever retaining wall—a seismic equivalence†

A procedure is presented to develop geometric dimensions and material property values for a model cantilever wall from those of a prototype counterfort wall such that the model wall will simulate the response of the prototype wall for seismic loads. The equivalency criteria are given. A sample problem is included to illustrate the use of the proposed procedure. Accuracy of results is discussed. Published in 2005 by John Wiley & Sons, Ltd.
Computational Discovery, Characterization, and Design of Single-Layer Materials

Single-layer materials open up tremendous opportunities for applications in nanoelectronic devices and energy technologies. We first review the four components of a materials science tetrahedron for single-layer materials. We then provide a theoretical perspective of characterizing single-layer materials. This leads to a general data-mining process to predict and computationally characterize emerging single-layer materials. Finally, we comment on limitations and possible improvements of current computational procedures for the discovery, characterization, and design of single-layer materials.
Sophisticated falsification and research cycles: Consequences for differential character weighting in phylogenetic systematics

Practicing phylogenetic systematics as a sophisticated falsification research program provides a basis for claiming increased knowledge of sister species relationships and synapomorphies as evidence for those cladistic propositions. Research in phylogenetic systematics is necessarily cyclic, and the place where the positive shift in understanding occurs is subsequent to discovering the most parsimonious cladogram(s). A priori differential character weighting is inconsistent with seeking the maximally corroborated cladogram (sensu Popper), because weighting adds to background knowledge, the evidence being then less improbable than it would be otherwise. Also, estimating weights from character state frequencies on a cladogram is inconsistent with the view that history is unique. Sophisticated falsification provides the place in the cycle of phylogenetic systematic research where weight of evidence can be evaluated and these inconsistencies do not apply. On balance, phylogenetic systematics appears to achieve greater coherence and generality as a result of focusing on the foundations for claiming increased knowledge and avoiding efforts to differentially weight characters.
Use of a computerized kiosk in an assessment of food safety knowledge of high school students and science teachers

A multimedia touch-screen kiosk was used to assess food safety knowledge and convey food safety principles to 93 high school science teachers and 165 students. The kiosk program based on the FightBAC messages informed users of correct responses and reasons for the response. Teachers correctly answered more questions than students; however, for the areas of hand washing, sources of foodborne illness, and handling of leftover foods, at least 40% of both students and teachers provided incorrect answers.
Software and Hardware Techniques for Power-Efficient HPC Networking

Although most large-scale systems are designed with the network as a central component, the interconnection network's energy consumption has received little attention. However, several software and hardware approaches can increase the interconnection network's power efficiency by using the network more efficiently or using throttling bandwidths to reduce the power consumption of unneeded resources.
HARTREE-FOCK TREATMENT OF EXCHANGE IN (E, 2E) COLLISIONS

The distorted-wave Born approximation has been very successful for treating electron-impact ionization (e,2e) of heavy atoms for high-energy incident electrons. However, as the energy of the incident electrons approaches threshold, significant differences between experiment and theory are observed. In these calculations, the continuum projectile electron wavefunction is typically calculated using the static field of the atom plus a local approximation for electron exchange. While this approximation is believed to be reasonable for higher energies, it is likely to become unreliable for energies near threshold. Here we report a proper treatment of electron exchange in which a full Hartree-Fock calculation is performed for both the atomic and projectile electrons. For the initial state, the projectile orbitals are calculated in the Hartree-Fock approximation with full exchange with the target electrons and for the final state, the Hartree-Fock continuum orbitals are computed for an ion. It is found that the static-exchange approximation is not valid for lower incident energy projectiles.
An object-oriented VLSI CAD framework

It is shown, in the context of an actual prototype VLSI CAD framework called Cbase, how concepts such as data abstraction, property and operation inheritance, object specialization/generalization, code reusability, and polymorphism offered by object-oriented database management systems (OODBMSs) support rapid prototyping. The work was conducted on Vbase, a commercially available OODBMS, but the results and conclusions apply to any database with comparable capabilities. To implement the prototype user interface, the X11 toolkit, a windowing package that is also built around the object paradigm, was used. >
Electronic structure of tubular aromatic molecules derived from the metallic (5,5) armchair single wall carbon nanotube.

All-electron static and time-dependent DFT electronic calculations, with complete geometrical optimization, are performed on tubular molecules up to C210H20 that are finite sections of the (5,5) metallic single wall carbon nanotube with hydrogen termination at the open ends. We find pronounced C−C bond reconstruction at the tube ends; this initiates bond alternation that propagates into the tube centers. For the especially low band gap molecules C120H20, C150H20, and C180H20, alternation increases, and a second nearly isoenergic structural isomer of different alternation is found. A small residual C−C bond alternation and band gap may be present in the infinite tube. The van Hove band gap forms quickly with length, while the metallic Fermi point (at the crossing of linear bands) forms very slowly with length. There are no end-localized states at energies near the Fermi energy. The HOMO−LUMO gap and the lowest singlet excited state, whose energies show a periodicity with length as previously calculated, ar...
Abstract 39: FANCA regulates MUS81-EME1 mediated DNA incision in a damage-dependent manner

MUS81-EME1 is a DNA endonuclease involved in replication-coupled repair of DNA interstrand crosslinks (ICL). A prevalent hypothetical role of MUS81-EME1 in ICL repair is to unhook the damage by incising the leading strand at the 3′ side of an ICL lesion. In this study, we report that purified MUS81-EME1 incises DNA at the 5′ side of a psoralen ICL residing in fork structures. Intriguingly, interstrand crosslink repair protein, FANCA, greatly enhances MUS81-EME1-mediated ICL incision. On the contrary, FANCA exhibits a two-phase incision regulation when DNA is undamaged or the damage affects only one DNA strand. Studies using truncated FANCA proteins indicate that both the N- and C-moieties of the protein are required for the incision regulation. Using laser-induced psoralen ICL formation in cells, we find that FANCA interacts with and recruits MUS81 to ICL lesions. This report clarifies the incision specificity of MUS81-EME1 on ICL damage and establishes that FANCA regulates the incision activity of MUS81-EME1 in a damage-dependent manner. Citation Format: Anaid Benitez, Fenghua Yuan, Satoshi Nakajima, Leizhen Wei, Liangyue Qian, Richard Myers, Jennifer J. Hu, Li Lan, Yanbin Zhang. FANCA regulates MUS81-EME1 mediated DNA incision in a damage-dependent manner. [abstract]. In: Proceedings of the AACR Special Conference: Cancer Susceptibility and Cancer Susceptibility Syndromes; Jan 29-Feb 1, 2014; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(23 Suppl):Abstract nr 39. doi:10.1158/1538-7445.CANSUSC14-39
Missteps in Multiple Regression Student Projects: Beyond Association-Not-Causation

This article describes common yet subtle errors that students make in self-designed multiple regression projects, based on experiences in a graduate business statistics course. Examples of common errors include estimating algebraic identities, overlooking suppression, and misinterpreting regression coefficients. Advice is given to instructors about helping students anticipate and avoid these common errors; recommended tactics include extensive written guidelines supplemented with in-class active-learning exercises. Several examples using real data are provided. Brief mention is made of incorporating these activities into online courses. Because self-designed student projects require significant effort from students and faculty, anticipating these common errors, and helping students circumvent them, can go a long way to making student projects a more satisfying experience for all.
On the identification of linear time-invariant systems

A new canonical form of state variable equations (for a linear time-invariant system) is developed. This canonical form has the specialty that the state variables can easily be generated using the integrals of the input and the observable ouput. This special property can be exploited to identify the parameters of the unknown system. If the system whose parameters are to be determined, is found to be stable, identification of the parameters is shown to be very simple. Non-zero initial conditions are handled very easily by a proper choice of the input (excitation) function. The calculation of the unknown parameters involves the determination of integrals (with the consequent suppression of any effect of measurement noise) and solution of a linear system of algebraic equations. It is not necessary, theoretically at least, to assume the order of the unknown system to be identified. The proposed method of identification, it is believed, adapts itself in the development of a lower order approximate model for the unknown system.
Clinical correlates of cerebral ventricular enlargement in schizophrenia. Further evidence for frontal lobe disease

Numerous studies have shown evidence of cerebral ventricular enlargement in schizophrenia and its relationship to severity of clinical symptoms and psychosocial dysfunction. In this large prospective study, 88 noninstitutionalized DSM-III-R schizophrenic patients were administered a CT scan and rated for positive and negative symptomatology and premorbid adjustment. The CT scans from 14 healthy controls were used for comparison of cerebral ventricular measures. Patients had an enlarged ventricle to brain ratio of the anterior portion of the lateral ventricles, the frontal horns, compared with controls. Patients with larger frontal horns had more severe negative symptoms and poorer premorbid childhood adjustment. The area of the main body of the cerebral lateral ventricles, though not elevated in patients, was correlated with the total number of prior hospitalizations. These results support the hypothesis of a structural and functional "frontal" deficit in schizophrenia.
Application of the electron channeling contrast imaging technique to the study of dislocations associated with cracks in bulk specimens

The application of the electron channeling contrast imaging (ECCI) technique to the study of dislocation behavior in the region of crack tips in high-purity stoichiometric single crystal NiAl is presented. Because the ECCI technique, which is based on the dependence of the intensity of backscattered electrons on the incident beam orientation with respect to the crystal lattice and defects near the specimen surface, allows near-surface defects to be imaged in bulk specimens, it has specific advantages over transmission electron microscopy approaches. The technique eliminates the tedious task of thin foil preparation and avoids many of the constraints imposed by the thin foils. Dislocations associated with crack propagation were observed by examining bulk 4-point bend specimens deformed in situ in a field emission gun scanning electron microscope. Dislocations were directly imaged in the crack tip region as well as along the crack paths. Crack deflection and blunting were observed to occur primarily by plastic zone formation in the immediate region of the crack tip.
Access to medication and drug company sales practices: Setting priorities for critique and advocacy

On April 16, federal prosecutors announced Bayer’s agreement to pay the government $257 million in a Medicaid fraud settlement. Afraid of losing business with insurance giant Kaiser Permanente, for ave years Bayer had sold the antibiotic Cipro to Kaiser at prices below those Bayer charged to Medicaid. Because a federal “best price” law requires manufacturers to sell to Medicaid at the lowest price available, Bayer hid the transactions by relabeling the drugs with Kaiser’s name and a new drug identiacation number. The scheme was only revealed when a whistle-blower released documents to the government. He noted that when Bayer executives at a 1999 ethics seminar were told to report any violations to the head of US operations, “the room had erupted in laughter.” (Petersen 2003)
Shi'i clerics in Iraq and Iran, 1722–1780: the Akhbari‐Usuli conflict reconsidered

It has long been held that the eighteenth century was a pivotal one in the history of Imami Shi'i thought and jurisprudence in Iraq and Iran. At the beginning of this era, it is said, the previously dominant Usuli school declined, and the conservative Akhbari school came to the fore. This intellectual revolution coincided with the fall of the Safavid dynasty in Iran and the disestablishment of Shilism under the Afghans and then Nadir Shah. Standard accounts would have us believe that Akhbarism became dominant. Then late in the century, as the Qajars came to power, the Usuli school staged a comeback in the shrine cities of Iraq and subsequently in Iran.1 This version of events, deriving from published nineteenth-century Usuli works, contains elements of truth. But an examination of manuscript sources from the period and of later biographical dictionaries suggests that the standard view needs revision. In particular, the periodization needs to be made more precise and the biographies of the major in
Brevetoxins 2, 3, 6, and 9 show variability in potency and cause significant induction of DNA damage and apoptosis in Jurkat E6-1 cells.

Brevetoxins (PbTx) are potent lipid soluble polyether neurotoxins produced by the marine dinoflagellate Karenia brevis, an organism linked to periodic red tide blooms. Brevetoxins exert their toxicity by interacting with neurotoxin receptor site five associated with domain IV of the alpha subunit of the voltage gated sodium channel. Brevetoxin binding to tissues that contain voltage gated sodium channels on excitable cells results in membrane depolarization, repetitive firing, and increase in sodium currents. Brevetoxins have been linked to deaths in marine mammals, which are exposed through ingestion of organisms harboring high brevetoxin concentrations and through the inhalation of aerosolized brevetoxins. Humans are also at risk, primarily through respiratory exposure which can result in a severe inflammatory response. The purpose of this study was to determine the effect of four brevetoxins on Jurkat E6-1 cell proliferation, to assess their variability in potency, genotoxicity, and to determine if brevetoxin causes cell death, specifically through an apoptotic or necrotic mechanism. PbTx 2, 3, 6, and 9 were tested at concentrations of 10−4–10−12 M to determine the IC50 values and effect on cell proliferation. The IC50 concentration was then used in the single cell gel electrophoresis assay to determine genotoxicity. The ability to induce apoptosis was then assessed with the Vybrant apoptosis assay, caspase activation assays and PARP cleavage. Results from the cellular proliferation assays demonstrated that high doses of PbTxs inhibit the ability of Jurkat cells to proliferate while lower doses caused an increase in proliferation and that PbTx2 is the most cytotoxic brevetoxin followed by brevetoxins 6, 3, and 9. Brevetoxins 2, 3, and 6 all caused significant DNA damage. A 4 h exposure to brevetoxins 2, 3, 6, and 9 at values close to the IC50 values resulted in apoptosis positive staining in Jurkat E6-1 cells. High doses of brevetoxins 2 and 6 resulted in activation of caspases 3/7 and 8 and cleavage of poly (ADP-ribose) polymerase (PARP). The conclusions are that brevetoxins affect cell proliferation in a dose-dependent fashion, are genotoxic, and cause cell death through an apoptotic mechanism.
Preparation of (η5-cyclopentadienyl) and (η5-methylcyclopentadienyl) Fe(CO)2 Me cyclodextrin inclusion compounds and their subsequent ligand substitution reactions. Attempts at cyclodextrin mediated enantioselective ligand substitution

Two iron complexes, (η5-Cyclopentadienyl)Fe(CO)2Me and (η5-Methylcyclopentadienyl)Fe(CO)2Me, were prepared followed by their α, β, and γ cyclodextrin inclusion compounds. The included iron complexes participate in phosphine induced ligand substitution reactions under both thermal and photochemical conditions with no CO insertion/alkyl migration products observed in either case.
Security for multimedia adaptation: architectures and solutions

Multimedia content adaptation enables users with different access networks, client devices, and/or user profiles to access the same information source. However, content adaptation also introduces security implications. We conduct an in-depth investigation into the potential security issues involved and analyze general security architectures and requirements. In particular, we address the issue of where to place the security functions and how this affects functionality.
Interaction effects in a multiple schedule of signaled and unsignaled reinforcement

Pigeons received baseline training on an equal-valued multiple unsignaled variable-interval/signaled variable-interval schedule. This procedure resulted in high and low response rates during the unsignaled and signaled components, respectively. Behavior during each component was then separately extinguished. Extinction of the unsignaled component resulted in positive contrast in the signaled variable-interval component. When reinforcement was withheld during the signaled component, marked increases in responding during this component occurred, and responding in the presence of the signal was very resistant to extinction. Accompanying the breakdown of the discrimination during the signaled component was an increase in the rate of responding in the unsignaled variable-interval component (i.e., positive induction). The implications of these results for several theories of behavioral contrast are considered.
Responses to Dissatisfaction in Romantic Involvements: A Multidimensional Scaling Analysis

Abstract Two multidimensional scaling studies were conducted to develop a comprehensive, inductively derived typology of responses to dissatisfaction in romantic involvements. Study 1 examined the responses of an undergraduate population, and Study 2 explored the reactions of a more heterogeneous, adult sample. The studies revealed similar patterns of results. In both Study 1 and Study 2, four general categories of response to dissatisfaction were observed: (a) exit—ending or actively abusing the relationship; (b) voice—actively attempting to improve conditions; (c) loyalty—passively waiting for conditions to improve; and (d) neglect—passively allowing the relationship to deteriorate. Two dimensions were distinguished among the response categories—constructiveness/destructiveness and activity/passivity. Voice and loyalty were judged to be constructive behaviors, while exit and neglect were viewed as relatively more destructive. And exit and voice were seen as fairly active, while loyalty and neglect were judged to be more passive (this effect was stronger in Study 1 than in Study 2). These findings provide good support for the Rusbult, Zembrodt, and Gunn (Journal of Personality and Social Psychology 1982, 43, 1230–1242) model of responses to dissatifaction in romantic involvements.
A new method of chaining carbon nanofibers in epoxy

In this paper, a new and innovative process for assembling chains of carbon nanofibers (CNFs) in epoxy, uniquely different from those generally used for chaining particles in a liquid medium, is presented. Chains of aligned CNFs are assembled in a region rich in CNFs and extended into regions where there are no CNFs. A physical explanation of the process is provided based on the conductive nature of the CNFs. By contacting the chains with the electrodes, the process of chain growth is expedited and well-ordered parallel chains with equal spacing are grown over distances of 2 cm.
Relating Online: Managing Dialectical Contradictions in Massively Multiplayer Online Role-Playing Game Relationships

The theory of dialectical contradictions (L. A. Baxter & B. M. Montgomery, 1996) is used to examine relationships developed in a Chinese online role-playing game, Legend of Mir. Analysis of discour...
Rhodium dimers with 2,2-dimethyl-1,3-diisocyano and bis(diphenylphosphino)methane bridging ligands.

Four rhodium dimers have been synthesized with a bridging diisocyanide ligand, dmb (2,2-dimethyl-1,3-diisocyanopropane): [Rh 2 (dmb) 4 ](BPh 4 ) 2 , [Rh 2 (dmb) 4 Cl 2 ]Cl 2 , [Rh 2 (dmb) 4 I 2 ](PF 6 ) 2 , and [Rh2(dmb)2(dppm)2](BPh4)2 (dppm = bis(diphenylphosphino)methane). The complexes have been characterized by elemental analysis and mass spectrometry, as well as UV-visible, IR, and 1 H NMR spectroscopies. X-ray crystal structures of the rhodium(I) complexes, [Rh 2 (dmb) 4 ](BPh 4 ) 2 ·1.5CH 3 CN (3.2330(4), 3.2265(4) A) and [Rh 2 (dmb) 2 (dppm) 2 ](BPh 4 ) 2 ·0.5CH 3 OH· 0.2H 2 O (3.0371(5) A), confirm the existence of short Rh···Rh interactions. The metal-metal separation for the rhodium(II) adduct, [Rh 2 (dmb) 4 Cl 2 ]Cl 2 ·6CHCl 3 (2.8465(6) A), is consistent with a formal Rh-Rh bond. For the two luminescent rhodium(I) dimers and six previously investigated diisocyano-bridged dimers with and without dppm ligands, the intense spin-allowed dσ*-pσ absorption band maximum shifts to longer wavelengths with decreasing Rh···Rh separation, and there is an approximate correlation between band energy and the inverse of the metal-metal separation cubed. Both [Rh 2 (dmb) 4 ] 2+ and [Rh 2 (dmb) 4 (dppm) 2 ] 2 + undergo oxidative addition in the presence of iodine. In the conversion of [Rh 2 (dmb) 4 ] 2+ to [Rh 2 (dmb) 4 I 2 ] 2+ , the observed intermediate is tentatively assigned to a tetramer composed of two rhodium dimers. In the case of [Rh 2 (dmb) 2 (dppm) 2 ] 2+ , no intermediate was detected.
The low-level structure and evolution of a dry arctic front over the central United States. Part I: Mesoscale observations

Abstract Observations taken over the period 8–10 March 1992 during the Storm-scale Operational and Research Meteorology Fronts Experiment Systems Test in the central United States are used to document the detailed low-level structure and evolution of a shallow, dry arctic front. The front was characterized by cloudy skies to its north side and clear skies to its south side. It was essentially two-dimensional in the zone of intense observations. There was a significant diurnal cycle in the magnitude of the potential temperature gradient across both the subsynoptic and mesoscale frontal zones, but imposed upon an underlying, more gradual, increase over the three days. On the warm (cloudless) side., the temperature increased and decreased in response to the diurnal heating cycle, while on the cold (cloudy) side the shape of the temperature decrease from its warm-side value (first dropping rapidly and then slowly in an exponential-like manner) remained fairly steady. The authors attribute the strong diurnal v...
Gambling on the Internet

This paper explores the political and social implications of the emerging online gambling industry and the ability of the existing legal framework to halt the industry's development. Making gambling more broadly available via the networks threatens heightened crime, an increased incidence of compulsive gambling, and cannibalized spending in other areas of the economy. Yet, U.S. state and federal laws are inadequate to deal with the onslaught of virtual gaming. States are unlikely to be able to prosecute out of state casino operators operating in cyberspace. Although they may be able to prosecute their own citizens for gambling on-line, enforcement will be difficult. Federal statutes may criminalize cyberspace casinos, but the U.S. government's ability to prosecute foreign operators is questionable. As existing legal frameworks prove inadequate to deal with a global, intangible entity, new legal, technological, and political solutions will have to be crafted in order to protect Americans from the substantial externalities posed by on-line gambling.
Freezing of Mixtures Confined in a Slit Nanopore

We report a Grand Canonical Monte Carlo study of the freezing/melting of Lennard-Jones A/B mixtures confined in a slit pore (H = 1.44 nm). The fluid/fluid interactions are chosen to model A = Ar and B = Kr. Fluid/wall interaction parameters are chosen so that the ratio of the wall/fluid to the fluid/fluid interactions for Kr and Ar is larger and smaller than 1, respectively. We find that the phase diagram of the confined mixture is of the same type than that for the bulk. The freezing temperature of confined mixtures rich in Kr is larger than the bulk. In contrast, we observe a decrease of the freezing temperature for mixtures rich in Ar. The confined crystal has a hexagonal structure (triangular symmetry), except for pure Ar where a square structure is observed.
Student Appropriation of Writing Lessons through Hybrid Composing Practices: Direct, Diffuse, and Indirect Use of Teacher-Offered Writing Tools in an ESL Classroom:

This is a qualitative case study (conducted in an urban, public school classroom in the United States) of the collaborative composing processes of two groups of first-grade students designated as English Language Learners (ELLs) as they wrote in a writing workshop context. I focused on a specific type of the students’ hybrid composing practices: those that featured them combining elements of their cultural and linguistic repertoires with writing tools offered by the teacher’s lessons. These hybrid composing practices served as a medium for the students to appropriate (Wertsch, 1998) the teacher-offered writing tools into their composing repertoires. I identified three types, or degrees, of student appropriation of lesson elements: direct, diffuse, and indirect. During direct appropriation, students incorporated elements from the writing lesson during the composing period immediately after the lesson. In cases of a diffuse or indirect relationship between the lesson and situated composing, students used lessons from previous days in unpredictable ways, used a broader theme or idea from the lesson, or transformed the purposes of the writing period to explore practices not anticipated by the lesson. Several pedagogical implications related to ELL-designated students’ uses of hybrid composing practices in workshop settings are also discussed.
Centrosomal protein CEP104 (Chlamydomonas FAP256) moves to the ciliary tip during ciliary assembly.

Summary The ciliary tip has been implicated in ciliary assembly and disassembly, and signaling, yet information on its protein composition is limited. Using comparative, quantitative proteomics based on the fact that tip proteins will be approximately twice as concentrated in half-length compared with full-length flagella, we have identified FAP256 as a tip protein in Chlamydomonas . FAP256 localizes to the tips of both central pair and outer doublet microtubules (MTs) and it remains at the tip during flagellar assembly and disassembly. Similarly, its vertebrate counterpart, CEP104, localizes on the distal ends of both centrioles of nondividing cells until the mother centriole forms a cilium and then localizes at the tip of the elongating cilium. A null mutant of FAP256 in Chlamydomonas and RNAi in vertebrate cells showed that FAP256/CEP104 is required for ciliogenesis in a high percentage of cells. In those cells that could form cilia, there were structural deformities at the ciliary tips.