cssi/SciSciGPT-SciSciNet huggingface dataset:
Tax evasion and intertemporal choice

It has often been argued that the misreporting of regular wage income is limited by third-party withholding and reporting requirements. However, income arising from savings investment is often not subject to such withholding requirements. This paper uses a simple dynamic model to examine the problem of tax evasion of investment income. Assuming that individuals can misreport investment income but not wage income, it is shown that alterations in the audit rate and penalty rates affect an individual's saving (or investment) decisions. This suggests that parameters traditionally used to control tax evasion impact the aggregate output of an economy and the rate of economic growth.
Porosity and composition effects in sol-gel derived interference filters

The effects of porosity and composition on the optical thickness of sol—gel films is analyzed using the Clausius-Mossotti relationship. The optical thickness is predicted to decrease with shrinkage approximately linearly. For high density films the predictions agree with experimental data from SiO2 and SiO2-TiO2-Al2O3 coatings. At low densities, however, the optical thicknesses are much higher than predicted by the Clausius-Mossotti analysis. This difference is attributed to residual species in the unfired films. Using an empirical value for the ratio of the electronic polarizability αr to the molecular weight Wr of the residual species (αr/Wr= 1.65 × 10−25cm3 mol g−1) the difference between experiment and theory is accounted for quantitatively for both the single-component (SiO2) and multicomponent (SiO2-TiO2-Al2O3) coatings. Approaches to fabricating multicolor dichroic filters, which require large changes in optical thickness on heating, are presented.
SU-E-T-120: Characterization of EBT2 Film for Absolute Dosimetry in Proton Beams

Purpose: The objective of this work is to fully characterize Gafchromic EBT2 film for absolute dose measurement (in‐vitro and in‐vivo) in the spread out Bragg peak (SOBP) of both scanned and scattered proton beams. Methods and Materials: The OD‐vs‐dose calibration curve is determined by irradiating film at different depths (0, 5, 10, 15, 20, and 25 cm) to different dose in a calibration field (range 28 g/cm2, modulation 15 g/cm2). Solid water slabs are used as phantom; 4x5 cm films are irradiated to nine dose levels spanning from 10 cGy to 1000 cGy. Beam output is measured using parallel plate ionization chamber both to calculate the specific doses delivered to the film and to compare the measured dose with the calculated dose from the film. The films are digitized with EPSON scanner and the net optical density computed. Measurement done at different depths (different average energy) are combined to create a single calibration curve. Verification measurements are performed for different range and modulation combinations, at various depths, and using both double‐scattering and uniform‐scanning delivery, thus validating the use of single sensitometric plot for different proton energy and delivery technique. In addition, reproducibility, angular response, and film uniformity are investigated. Results: Using the single calibration curve, the accuracy of absolute dose measurements using EBT2 film is found to be within 5% for any point within the SOBP excluding the distal fall off region and at very low dose level (<15cGy). No difference in response to scattering or scanning beams is observed. The day‐to‐day reproducibility is better than 1%. The uncertainty introduced by angular response, film nonuniformity and different delivery techniques are found to be insignificant. Conclusions: EBT2 film is a viable option for absolute dose measurements both for in‐vitro and in‐vivo.
Effects of Cu-substitution on La0.62Ce0.38(NiCoMnAlSiZr)5.3 metal hydride alloy

Abstract Five Pr, Nd-free hyper-stoichiometric AB 5 metal hydride alloys, having nominal alloy compositions of La 9.5 Ce 6.4 Ni 69.0− x Co 4.7 Mn 4.3 Al 5.7 Cu x Zr 0.1 Si 0.3 ( x = 0, 1, 2, 3, 4) with Cu partially substituting for Ni, were prepared by induction melting. The structure, chemical composition, gaseous phase hydrogen storage properties, and electrochemical properties of these alloys were investigated. Both the as-cast and annealed (960 °C for 10 h in vacuum) alloys were made of a single CaCu 5 -type structure. Annealing improved the composition homogeneity, enlarged the crystallite size, and flattened the pressure-concentration-temperature isotherm. The occupancy site of Cu followed the sequence of 3g (1 at.% Cu) → 2c (2 and 3 at.% Cu) → 3g (4 at.% Cu). Improvement in activation and high-rate performance was demonstrated for the alloy containing 1 at.% Cu, but deterioration in the aforementioned properties were observed with higher Cu-content. With the incorporation of Cu, although the unit cell volume increased, both the gaseous phase and electrochemical hydrogen storage capacities decreased. 1 at.% Cu-substituted alloy showed both higher bulk diffusion constant and surface exchange current than commercially available AB 5 metal hydride alloys and was recommended for high-power nickel/metal hydride battery applications.
A comparison of HIV seropositive and seronegative young adult heroin- and cocaine-using men who have sex with men in New York City, 2000–2003

The purpose of this analysis was to determine the prevalence and correlates of HIV infection among a street-recruited sample of heroin-and cocaine-using men who have sex with men (MSM). Injection (injecting ≦3 years) and non-injection drug users (heroin, crack, and/or cocaine use<10 years) between 18 and 40 years of age were simultaneously street-recruited into two cohort studies in New York City, 2000–2003, by using identical recruitment techniques. Baseline data collected among young adult men who either identified as gay/bisexual or reported ever having sex with a man were used for this analysis. Nonparametric statistics guided interpretation. Of 95 heroin/ cocaine-using MSM, 25.3% tested HIV seropositive with 75% reporting a previous HIV diagnosis. The majority was black (46%) or Hispanic (44%), and the median age was 28 years (range 18–40). HIV-seropositive MSM were more likely than seronegatives to be older and to have an HIV-seropositive partner but less likely to report current homelessness, illegal income, heterosexual identity, multiple sex partners, female partners, and sex for money/drug partners than seronegatives. These data indicate high HIV prevalence among street-recruited, drug-using MSM compared with other injection drug use (IDU) subgroups and drug-using MSM; however, lower risk behaviors were found among HIV seropositives compared with seronegatives. Large-scale studies among illicit drug-using MSM from more marginalized neighborhoods are warranted.
The crystal structure of dilanthanum dioxidedicarbide, La2O2C2

The crystal structure of La2O2C2 was determined from three dimensional X-ray diffraction data obtained with Mo radiation (λα1 = 0.7093 A) on a twinned crystal. The structure is of monoclinic symmetry, space group C2m, with z = 2. Lattice parameters are, a = 7.069(8), b = 3.985(4), c = 7.310(9) A and β = 95.70(6)°; the calculated density is 5.41 g cm−3. The twinning mechanism, a 120 ° rotation about c∗ or a slippage of the (001) cleavage plane, is explained in the light of the structural solution. Intensity data collected from each of the twinned fragments were merged for the final refinement, which yielded an unweighted discrepancy index, R, based on F, of 0.032. The lanthanum atom has four oxygen and four carbon atoms situated in a distorted bicapped trigonal prismatic arrangement. Interatomic La-O distances range from 2.392(8) to 2.823(9) A and La-C distances from 2.86(1) to 3.11(1) A. The carbon atoms are present as C2 units with an interatomic C-C distance of 1.21(3) A. Oxygen atoms are tetrahedrally coordinated, as in the sesquioxide.
Combining Radiation and Immunotherapy: A New Systemic Therapy for Solid Tumors?

With the recent success of checkpoint inhibitors and other immunomodulating agents, there has been renewed interest in the combination of such agents with radiation. The biologic premise behind such a strategy is that the tumor-antigen release achieved by localized radiation will promote specific tumor targeting by the adaptive immune system, which can be augmented further by systemic immune-stimulating agents. In this manner, clinicians hope to induce a phenomenon known as the abscopal effect, whereby localized radiation results in immune-mediated tumor regression in disease sites well outside of the radiation field. Herein, we present a comprehensive overview of the early clinical and preclinical evidence behind this approach.
Numerical simulation of III-nitride lattice-matched structures for quantum cascade lasers

We present a comparison among GaN/AlGaN, GaN/InAlGaN, and GaAs/AlGaAs quantum cascade structures based on a Monte Carlo study of carrier dynamics, to highlight the improvements offered by nitride latticematched structures. We take into account the interactions of electrons with other electrons as well as LO-phonons. The results obtained from the Monte Carlo simulations are used to calculate the population inversion of each structure to determine its temperature dependence. This study shows that the nitride-based structures offer significantly improved high-temperature performance compared to the GaAs device, including the possibility of room-temperature operation. Furthermore, by virtue of its lattice-matched nature, the GaN/InAlGaN materials system can potentially enable the high-quality growth of thick quantum cascade structures without plastic relaxation, as a way to overcome the structural issues that have so far hindered the development of these devices with nitride semiconductors.
Phase reconstruction in optical interferometry

Abstract A method is presented for phase reconstruction in optical interferometry. It measures the phase differences of the object between spatial frequencies corresponding to adjacent wavelengths in the spectrum. Results of a computer simulation with a two telescope optical interferometer are included.
Implications of a Weaker Form of Complementarity

When a non-market good has existence value, the assumption of weak complementarity cannot be used to determine willingness to pay for that good. However, when this assumption is weakened, it is possible to place an upper bound on marginal willingness to pay even when the non-market good has existence value, and thereby, an upper bound on willingness to pay for changes in consumption of non-market goods can be established. Moreover, this upper bound may be relatively easy to compute.
Invariant principles of speech motor control that are not language-specific.

AbstractBilingual speakers must learn to modify their speech motor control mechanism based on the linguistic parameters and rules specified by the target language. This study examines if there are aspects of speech motor control which remain invariant regardless of the first (L1) and second (L2) language targets. Based on the age of academic exposure and proficiency in L2, 21 Bengali–English bilingual participants were classified into high (n = 11) and low (n = 10) L2 (English) proficiency groups. Using the Optotrak 3020 motion sensitive camera system, the lips and jaw movements were recorded while participants produced Bengali (L1) and English (L2) sentences. Based on kinematic analyses of the lip and jaw movements, two different variability measures (i.e., lip aperture and lower lip/jaw complex) were computed for English and Bengali sentences. Analyses demonstrated that the two groups of bilingual speakers produced lip aperture complexes (a higher order synergy) that were more consistent in co-ordinatio...
Evaluation of facsimile cards for pharmacy-access products containing pseudoephedrine or ephedrine

Abstract Objective To evaluate label characteristics (type size) of facsimile cards, which are placed in nonprescription-product areas of pharmacies to provide drug-related information and guide consumers to the pharmacist for pharmacy-access medications containing pseudoephedrine or ephedrine. Design: Cross-sectional. Setting: Six of eight major community chain pharmacies and grocery stores in Houston during the month of February 2006 that carried facsimile cards. Participants: Not applicable. Intervention: 187 facsimile cards for brand-name and generic pharmacy-access medications containing pseudoephedrine or ephedrine were evaluated for readability of information provided. Type size of printed drug-related information was measured with a compugraphic point system scale (1 inch=72 points). Main outcome measure: Readability of label characteristics, particularly type size, of printed information for brand-name and generic pharmacy-access medications containing pseudoephedrine or ephedrine. Results Median type size of drug-related printed information on facsimile cards was 4.00 points. For 172 cards (91.98%), the type size of printed information was below the Food and Drug Administration requirement of 6 points for nonprescription medication labeling. Conclusion Because of small type size, consumers may have difficulty reading information on facsimile cards for pharmacy-access products. Federal regulations or voluntary efforts are needed to improve and standardize information on facsimile cards for pharmacy-access medications.
Distributed penalty-based beamforming design for multi-source multi-destination networks

In this paper, a penalty-based distributed algorithm is proposed to design beamforming for multi-source multi-destination (MSMD) networks. The objective of the beamforming design is to minimize the transmission power of each source under the constraint that the signal-to-interference-plus-noise ratio (SINR) requirements of all source-destination pairs are satisfied. The proposed beamforming design has better power-efficiency compared to the egoism, altruism, and balancing algorithms. The convergence of the proposed algorithm is also discussed and a sufficient condition is determined for the algorithm to converge to a Pareto optimal solution. Simulation results show that the proposed algorithm has higher probability of convergence compared to the egoism, altruism, and balancing algorithms, which is close to a centralized performance benchmark.
Inhibitory neurons in human cortical circuits: substrate for cognitive dysfunction in schizophrenia

Schizophrenia is a disorder of cognitive neurodevelopment. At least some of the core cognitive deficits of the illness appear to be the product of impaired gamma frequency oscillations which depend, in part, on the inhibitory actions of a subpopulation of cortical GABA neurons that express the calcium binding protein parvalbumin (PV). Recent studies have revealed new facets of the development of PV neurons in primate neocortex and of the nature of their molecular alterations in individuals with schizophrenia. Other recent studies in model systems provide insight into how these alterations may arise in the course of cortical circuitry development.
Conserved promoter motif is required for cell cycle timing of dnaX transcription in Caulobacter.

Cells use highly regulated transcriptional networks to control temporally regulated events. In the bacterium Caulobacter crescentus, many cellular processes are temporally regulated with respect to the cell cycle, and the genes required for these processes are expressed immediately before the products are needed. Genes encoding factors required for DNA replication, including dnaX, dnaA, dnaN, gyrB, and dnaK, are induced at the G1/S-phase transition. By analyzing mutations in the dnaX promoter, we identified a motif between the 210 and 235 regions that is required for proper timing of gene expression. This motif, named RRF (for repression of replication factors), is conserved in the promoters of other coordinately induced replication factors. Because mutations in the RRF motif result in constitutive gene expression throughout the cell cycle, this sequence is likely to be the binding site for a cell cycle-regulated transcriptional repressor. Consistent with this hypothesis, Caulobacter extracts contain an activity that binds specifically to the RRF in vitro. The cell cycle of Caulobacter crescentus requires that the transcription of many genes be temporally regulated. In fact, the transcription of ;20% of the genes in Caulobacter is regulated as a function of the cell cycle (6). In some cases, the elements that mediate cell cycle-regulated transcription have been characterized, most notably those that are controlled by the response regulator CtrA (11). CtrA controls approximately one-fourth of the cell cycle-regulated genes (6), but little is known about the factors that are responsible for the regulation of the remaining three-fourths of the genes. In many cases, genes that are required for a cell cycle-regulated process are
A KELLOGG FOUNDATION INITIATIVE: COMMUNITY PARTNERSHIPS — SOUTH AFRICA

Summary Health personnel education in South Africa is currently directed towards preparation for work in tertiary care settings, is highly specialized, and segmented racially. The majority of South Africans are in desperate need of primary health care services. In preparing for transition to a future South Africa, a community-partnership effort is in its initial stages to redress this imbalance.
Ultrastructural localization and x-ray analysis of calcium-induced electron-dense deposits in the skate retina.

Abstract The technique of Oschman & Wall (1972) was used to visualize the sites at which electron-dense deposits accumulate in neural layers of the skate retina. The method, which involves the addition of calcium to the primary fixative, resulted in the formation of electron-dense deposits along the plasma membranes of horizontal cells, within the outer segments, mitochondria and synaptic vesicles of the visual cells, and at pre- and postsynaptic membranes of the synaptic elements of the outer plexiform layer. Energy dispersive X-ray spectrometry of the electron-dense deposits yielded prominent peaks for calcium and phosphorus. In the dark-adapted retina, the electron-dense deposits were seen more frequently in association with the receptor terminal than with the processes of second-order neurons; after light adaptation, the reverse situation was observed. A light-induced translocation of electron-dense deposits was not found at any other retinal location. The addition of cobalt to the fixative in lieu of calcium produced results equivalent to those obtained with calcium; i.e. electron-dense deposits were formed at simular loci within the retina. The emergence in the X-ray spectrum of a small calcium signal in the presence of a large cobalt peak suggests that the two ions compete for similar membrane sites. On the other hand, the formation of electron-dense deposits was suppressed completely by exposing the retinas to Ca 2+ -free solutions, with or without the addition of Mg 2+ . These findings are consistent with physiological observations that suggest that Mg 2+ and Co 2+ act at different sites in modifying the actions of Ca 2+ at synapses.
New Efficient Sparse Space–Time Algorithms for Superparameterization on Mesoscales

Abstract Superparameterization (SP) is a large-scale modeling system with explicit representation of small-scale and mesoscale processes provided by a cloud-resolving model (CRM) embedded in each column of a large-scale model. New efficient sparse space–time algorithms based on the original idea of SP are presented. The large-scale dynamics are unchanged, but the small-scale model is solved in a reduced spatially periodic domain to save the computation cost following a similar idea applied by one of the authors for aquaplanet simulations. In addition, the time interval of integration of the small-scale model is reduced systematically for the same purpose, which results in a different coupling mechanism between the small- and large-scale models. The new algorithms have been applied to a stringent two-dimensional test suite involving moist convection interacting with shear with regimes ranging from strong free and forced squall lines to dying scattered convection as the shear strength varies. The numerical ...
Recent advances in chlorophyll biosynthesis

The importance of chlorophyll (Chl) to the process of photosynthesis is obvious, and there is clear evidence that the regulation of Chl biosynthesis has a significant role in the regulation of assembly of the photosynthetic apparatus. The understanding of Chl biosynthesis has rapidly advanced in recent years. The identification of genetic loci associated with each of the biochemical steps has been accompanied by a greater appreciation of the role of Chl biosynthesis intermediates in intracellular signaling. The purpose of this review is to provide a source of information for all the steps in Chl and bacteriochlorophyll a biosynthesis, with an emphasis on steps that are believed to be key regulation points.
Docetaxel metabolism is not altered by imatinib: findings from an early phase study in metastatic breast cancer.

Docetaxel is primarily metabolized by CYP3A4 and susceptible to alterations in clearance by CYP3A4 inhibition and induction. Imatinib is a CYP3A4 inhibitor. A phase I study of docetaxel and imatinib in metastatic breast cancer (MBC) was conducted to test the hypothesis that imatinib decreased docetaxel clearance. Docetaxel was administered weekly × 3 with daily imatinib, repeated every 28 days; during cycle 1, imatinib was started on day 8. Docetaxel and imatinib pharmacokinetics, and hepatic CYP3A4 activity (erythromycin breath test) were evaluated during cycles 1 and 2. Toxicity and efficacy were assessed. Twelve patients were enrolled to three docetaxel/imatinib dose levels: 20 mg/m2/600 mg (DL1), 25 mg/m2/600 mg (DL2), and 25 mg/m2/400 mg (DL2a). Median number of prior chemotherapy regimens was 2 (range, 0–8). Toxicities were primarily observed at DL2; dose-limiting toxicities were Grade 3 transaminase elevations and diarrhea, and 5 patients had grade 2 nausea. Two patients had partial responses (7 months); two stable disease (2 and 4 months); five had progressive disease. Despite a 42% decrease in CYP3A4 activity after 3 weeks of imatinib co-administration, docetaxel clearance was unchanged. Mean ± standard deviation steady-state imatinib trough concentration (2.6 ± 1.2 μg/ml) was approximately 2.6-fold higher than previously observed in other cancer populations, and likely contributed to the poor tolerability of the combination in MBC. In conclusion, imatinib inhibited CYP3A4 but did not affect docetaxel clearance. Clinically, further investigation of this combination in MBC is not warranted due to excessive toxicities. However, these unexpected pharmacokinetic findings support further investigation of mechanisms underlying docetaxel elimination pathways.
Complement susceptibility in glutamine deprived breast cancer cells.

Background Membrane complement regulatory proteins (mCRPs) inhibit complement-mediated killing of human cells by human complement, a property that confers protection from complement to malignant breast cancer cells and that thwarts some immunotherapies. Metabolic mechanisms may come into play in protecting cancer cells from the complement system subsequent to relatively low levels of complement deposition.
Applying thermal imaging software to cattle grazing winter range

Abstract 1. Metabolic demands of cattle grazing winter range may be over-predicted by models that do not account for animal behavior. Cattle may conserve energy and mitigate cold stress by short-term behavioral responses. 2. We solved the thermal balance equation for a revolving three-dimensional model using advanced thermal solution software to simulate unconstrained cattle during winter. This software, developed for inanimate objects, predicted energetic requirements within expected range of values. 3. Solar radiation and apparent surface area were instrumental in reducing energy requirements, especially on cold clear days, whereas wind velocity and ambient temperature had a lesser effect on well-insulated cows in good body condition.
Prone thoracoscopic thoracic duct ligation for postsurgical chylothorax

Background Chylothorax after complex abdominal and thoracic procedures remains a challenging complication with a mortality rate reaching 50% if untreated [1]. Iatrogenic trauma accounts for almost 20% of all chyle leaks, and esophagectomy is the most common iatrogenic cause [2]. Consequences of ongoing chyle leak include dehydration, malnutrition, and immunocompromise.
Medical robotics in computer-integrated surgery

This paper provides a broad overview of medical robot systems used in surgery. After introducing basic concepts of computer-integrated surgery, surgical CAD/CAM, and surgical assistants, it discusses some of the major design issues particular to medical robots. It then illustrates these issues and the broader themes introduced earlier with examples of current surgical CAD/CAM and surgical assistant systems. Finally, it provides a brief synopsis of current research challenges and closes with a few thoughts on the research/industry/clinician teamwork that is essential for progress in the field.
Selective intraarterial methylene blue for pancreatic and duodenal endocrine tumors

Pancreatic and duodenal endocrine tumors can be difficult to localize intraoperatively. Three patients are described in whom selective intraarterial injection of methylene blue was used to correctly identify the position of an endocrine tumor. These patients had a duodenal gastrinoma, a pancreatic polypeptide-producing pancreatic islet cell tumor, and a duodenal somatostatinoma, respectively. Selective arterial secretin injection with hepatic vein gastrin measurement and selective arterial calcium injection with hepatic vein pancreatic polypeptide measurement were used to preoperatively identify the feeding artery. The duodenal somatostatinoma was identified by endoscopy. A catheter placed in the feeding artery just prior to surgery was used for injection of the methylene blue. The combination of selective arterial stimulation and selective arterial methylene blue injection is a promising method for helping surgeons localize elusive endocrine tumors in the duodenum and pancreas.
The height of a binary search tree: the limiting distribution perspective

We study the height of the binary search tree--the most fundamental data structure used for searching. We assume that the binary search tree is built from a random permutation of n elements. Under this assumption, we study the limiting distribution of the height as n → ∞. We show that the distribution has six asymptotic regions (scales). These correspond to different ranges of k and n, where Pr{Hn ≤ k} is the height distribution. In the critical region (the so-called central region), where most of the probability mass is concentrated, the limiting distribution satisfies a non-linear integral equation. While we cannot solve this equation exactly, we show that both tails of the distribution are roughly of a double exponential form. From our analysis, we conclude that the average height E[Hn] ∼ A log n - 3/2[A/(A-1)]log log n, where A = 4.311 ... is the unique solution of x logx - x - xlog2 + 1 = 0, x > 1, while the variance Var[Hn] = O(1). The second term in the expansion of E[{kn] and the rate of growth of the variance were also recently obtained by B. Reed who used probabilistic arguments, while M. Drmota established the growth of the variance by analytic methods. Our analysis makes certain assumptions about the forms of some asymptotic expansions, as well as their asymptotic matching.
Collection of process data after cardiac surgery: initial implementation with a Java-based intranet applet

Abstract Background . Using a Java-based intranet program (applet), we collected postoperative process data after coronary artery bypass grafting. Methods . A Java-based applet was developed and deployed on a hospital intranet. Briefly, the nurse entered patient process data using a point and click interface. The applet generated a nursing note, and process data were saved in a Microsoft Access database. In 10 patients, this method was validated by comparison with a retrospective chart review. In 45 consecutive patients, weekly control charts were generated from the data. When aberrations from the pathway occurred, feedback was initiated to restore the goals of the critical pathway. Results . The intranet process data collection method was verified by a manual chart review with 98% sensitivity. The control charts for time to extubation, intensive care unit stay, and hospital stay showed a deviation from critical pathway goals after the first 20 patients. Feedback modulation was associated with a return to critical pathway goals. Conclusions . Java-based applets are inexpensive and can collect accurate postoperative process data, identify critical pathway deviations, and allow timely feedback of process data.
Teachers' Discoveries of Their Cultural Realms: Untangling the Web of Cultural Identity

Educators need to explore and understand their own cultural identities before they can comprehend and appreciate their students' cultural backgrounds. In this article, the author presents the findings from a qualitative study that investigated in-service teachers' awareness of and characterization of their culture. She also discusses the importance of affording educators opportunities to reflect on and make the connection between culture and their worldview. The author concludes by recommending useful and practical next steps once teachers have a better understanding of their cultural identities.
Immunocompetent Cells in the Normal Dental Pulp

The existence and location of various immunocompetent cells in the human dental pulp were investigated. Pulp tissue for analysis was obtained both from clinically intact pre-molars and from third molars without restorations or caries. Frozen and acetone-fixed pulp tissue sections were subjected to indirect immunohistochemistry with monoclonal antibodies to the following cell types: all peripheral T cells, helper/inducer T cells, cytotoxic/suppressor T cells, macrophages, B cells, and Class II antigen-expressing cells. Dendritic cells expressing Class II antigens (HLA-DR, -DQ), indicating a capacity for presentation of antigen to T helper cells, were seen in the odontoblastic layer as well as in the central portions of the pulp tissue. T lymphocytes, divided into helper/inducer and cytotoxic/suppressor cells, were observed in all pulp specimens. B cells were not seen in any of the pulp samples examined. The data demonstrate that the human dental pulp is equipped with immunocompetent cells essential for the initiation of immunological responses.
Africa does not need IFRS

A great deal of hype surrounds the so-called revolution in accounting standard setting. The International Financial Reporting Standards (IFRS) enterprise aims to introduce a single global accounting and financial reporting language that would standardise reporting practices throughout the globe. There are several reasons why this vision may not hold, and therefore Africa should be wary. First, there are many obstacles for any US option. Second, International Financial Standards Board (IFSB) has failed to create a uniform set of standards.
BRAIN BILIRUBIN INFLUX IS INCREASED IN BLOOD-BRAIN-BARRIER P-GLYCOPROTEIN DEFICIENT NULL MUTANT MICE. • 1102

P-glycoprotein (P-gp) is an ATP-dependent plasma membrane protein that blocks the cellular influx and/or increases the cellular efflux of a wide variety of unrelated amphipathic compounds. P-gp is constituitively expressed in many tissues including the endothelial cells of the blood-brain-barrier and is encoded for by the MDR1a gene. Although P-gp expression is known to confer a multiple drug resistance phenotype to tumors that express it, an endogenous substrate for P-gp has not been defined. We hypothesized that bilirubin is a substrate for P-gp and that bilirubin transport across the blood-brain-barrier into the central nervous system would be increased in the absence of P-gp expression in brain endothelial capillary cells. We tested this hypothesis using adult MDR1a null mutant transgenic mice (MDR1a[-/-], Cell 77:491-502, 1994). Fifteen MDR1a[-/-] P-gp null mutants and 15 wild type [+/+] mice of the same mixed genetic background were lightly anesthetized and 50 mg/kg of bilirubin infused through the tail vein. Ten or 60 min following infusion the animals were sacrificed, brain vasculature flushed with saline in situ, and brain bilirubin content and serum bilirubin levels determined. Brain bilirubin content (mean±SEM) was significantly higher in MDR1a[-/-] P-gp deficient mice (10.6±1.4 ug/G [n=9]) as compared with wild type [+/+] mice (6.1±0.7 ug/G [n=8]) 10 min following infusion (P<0.05). Brain bilirubin content declined in both groups at the 60 min time point but was higher in MDR1a[-/-] mice (6.2±1.1 ug/G [n=6]) as compared with the wild type [+/+] (3.0±0.5 ug/G [n=7]) (P<0.05). Brain bilirubin clearance, however, did not differ between groups (t1/2 ≈ 55 min). Serum bilirubin levels declined from 10 to 60 min but did not differ between MDR1a [-/-] and [+/+] animals. We conclude that MDR1a[-/-] P-gp deficient mice have significantly higher brain bilirubin content compared with P-gp sufficient controls following an intravenous load of bilirubin. These data suggest that i) bilirubin is a substrate for P-gp and ii) the increased brain bilirubin content in MDR1a[-/-] mice is due to enhanced brain bilirubin influx rather than impaired efflux. We speculate that brain capillary endothelial cell P-gp expression provides a protective effect against bilirubin neurotoxicity by reducing brain bilirubin influx.
The effect of vacuum-mixed autopolymerizing acrylic resins on porosity and transverse strength

Three brands of autopolymerizing acrylic resin were mixed and polymerized three different ways and tested for transverse strength and porosity. The procedures tested were bench-curing at ambient temperatures, vacuuming the mix before bench-curing, and curing in a pressure device. The data indicate that both vacuuming the mix and pressure-curing are successful in reducing porosity and increasing transverse strength. These improved properties would be valuable in the fabrication of provisional restorations and occlusal splints. The following conclusions can be drawn: 1. Use of a pressure device decreases porosity and increases the transverse strength in samples of autopolymerizing acrylic resin. 2. Use of a vacuum device on the mixed acrylic resin works as well as pressure polymerizing. 3. Use of either technique is indicated to improve the quality and longevity of autopolymerizing acrylic resin restorations, orthodontic appliances, and occlusal splints.
Inferring Rates of Change in Flower Symmetry in Asterid Angiosperms

Discrete, version 1.01b (Pagel, 1997), is a DOS-based program that can be used to estimate individual ancestral values. Discrete was written to test for correlated evolution between twodiscrete characters, and producing ancestor reconstructions in such away requires several steps. First, Discrete deals with two characters at a time; therefore, for thepurposes of estimating ancestors for a single character, the states must be entered twice. For example, for a tip (tipA) in state 1 on a branch 2units long andwhose immediate ancestor is nodeA, the entry would be “tipA, nodeA, 2, 1,1.” Because two characters are input, Discrete estimates two (or four) rates: a 1 and b 1 refer to q01 and q10 for the rst character, and a 2 and b 2 refer to q01 and q10 for the second character. With this in mind:
Output aiming control

The problem of aiming control, introduced in [1], is extended to systems with outputs. Necessary and sufficient conditions for output residence time controllability in linear SISO systems with small, additive noise are derived. Controller design techniques are developed and applied to aircraft and robotics control problems. The approach is based on an extension of the asymptotic first passage time theory to output processes.
On reduced-complexity iterative channel tracking in turbo coded OFDM

This paper proposes a receiver that combines iterative channel updates with iterative turbo decoding for high mobility OFDM systems. We particularly focus on reducing the number of the channel update iterations and the complexity of each iteration. A low-complexity time-frequency channel estimator is proposed that tracks the channel variation within one code window and predicts the channel for the next window. The channel estimator can use simple hard decisions or more computationally intensive "soft" decisions, in which case the estimator is derived from an expectation-maximization (EM) principle. Simulation results are provided under a varying number of channel updates that use hard or soft decisions. As an example, a very simple hard decision based receiver for a rate-1/2 turbo coded 16 QAM OFDM system performs within 1 dB of a pilot-based receiver at 500 Hz Doppler, after three channel iterations that are interlaced with eight max-log-MAP decoding iterations. The proposed techniques can significantly reduce pilot symbol overhead with minimal performance degradation.
Adventures in a Strange Paradise - Utopia in “Nicolai Klimii Iter subterraneum”*

Ludvig Holberg's Niels Klim provides an example of a text in which a therne common to eighteenth-century Europe - the utopian vision - intersects with a literary convention common to Western letters - the descent to the world below through a cave. Originally written in Latin in order that it be read throughout Europe, the book contains several aspects characteristic of the Zeitgeist of eighteenth-century philosophical and literary thought while, at the same time, its treatment of the utopian theme may well point to a possible standard by which the synoptic depictions of utopia may be distinguished from those belonging to the much larger number of more traditional utopian texts written in a century that was to a great degree obsessed with the notion of creating a perfect society.
Egocentric context-aware programming in ad hoc mobile environments

Some of the most dynamic systems being built today consist of physically mobile hosts and logically mobile agents. Such systems exhibit frequent configuration changes and a great deal of resource variability. Applications executing under these circumstances need to react continuously and rapidly to changes in operating conditions and must adapt their behavior accordingly. The development of such applications demands a reexamination of the notion of context and the mechanisms used to manage the application's response to contextual changes. This paper introduces EgoSpaces, a coordination model and middleware for ad hoc mobile environments. EgoSpaces focuses on the needs of application development in ad hoc environments by proposing an agent-centered notion of context, called a view, whose scope extends beyond the local host to data and resources associated with hosts and agents within a subnet surrounding the agent of interest. An agent may operate over multiple views whose definitions may change over time. An agent uses declarative specifications to constrain the contents of each view by employing a rich set of constraints that take into consideration properties of the individual data items, the agents that own them, the hosts on which the agents reside, and the physical and logical topology of the ad hoc network. This paper formalizes the concept of view, explores the notion of programming against views, discusses possible implementation strategies for transparent context maintenance, and describes our current prototype of the system. We include examples to illustrate the expressive power of the view abstraction and to relate it to other research on coordination models and middleware.
Isobutanol production at elevated temperatures in thermophilic Geobacillus thermoglucosidasius

The potential advantages of biological production of chemicals or fuels from biomass at high temperatures include reduced enzyme loading for cellulose degradation, decreased chance of contamination, and lower product separation cost. In general, high temperature production of compounds that are not native to the thermophilic hosts is limited by enzyme stability and the lack of suitable expression systems. Further complications can arise when the pathway includes a volatile intermediate. Here we report the engineering of Geobacillus thermoglucosidasius to produce isobutanol at 50 °C. We prospected various enzymes in the isobutanol synthesis pathway and characterized their thermostabilities. We also constructed an expression system based on the lactate dehydrogenase promoter from Geobacillus thermodenitrificans. With the best enzyme combination and the expression system, 3.3 g/l of isobutanol was produced from glucose and 0.6 g/l of isobutanol from cellobiose in G. thermoglucosidasius within 48 h at 50 °C. This is the first demonstration of isobutanol production in recombinant bacteria at an elevated temperature.
An Identity Crisis for a Cancer Gene: Subcellular Location Determines ASPP1 Function

Two recent papers in Genes and Development argue that the ASPP1 protein has distinct roles in cell survival, depending upon its subcellular localization, that are determined by a complex interplay with LATS kinase and the YAP transcriptional cofactor.
Layering techniques for space-time communication in multi-user networks

In this paper, we consider a multiuser communication network where all the nodes in the network are equipped with multiple antennas and different users are identified through their spatial signatures. We present some results on the capacity of such networks. We consider two cases of interest: (i) when the transmitter (the base) has full knowledge of the channel state information (CSI) between itself and the receiving nodes (users); and (ii) when the base does not have CSI, but it does know which users currently have the best channel (e.g., measured in terms of a condition number). In the first case, we establish coordinated beamforming between the base and a number of users to whom data is to be transmitted. In the second case, partial knowledge of the quality of the users' channels will be used to transmit data to the users with better channel condition, without performing any beamforming at the base. In both cases, the base transmits independent data streams to multiple users. This guarantees a higher minimum quality of service for all the users compared to the case where the user with the best channel is selected and all the available capacity is devoted to it. In addition, we show that this approach may increase the overall capacity/throughput of the network.
Defective mitochondrial gene expression results in reactive oxygen species-mediated inhibition of respiration and reduction of yeast life span.

Mitochondrial dysfunction causes numerous human diseases and is widely believed to be involved in aging. However, mechanisms through which compromised mitochondrial gene expression elicits the reported variety of cellular defects remain unclear. The amino-terminal domain (ATD) of yeast mitochondrial RNA polymerase is required to couple transcription to translation during expression of mitochondrial DNA-encoded oxidative phosphorylation subunits. Here we report that several ATD mutants exhibit reduced chronological life span. The most severe of these (harboring the rpo41-R129D mutation) displays imbalanced mitochondrial translation, conditional inactivation of respiration, elevated production of reactive oxygen species (ROS), and increased oxidative stress. Reduction of ROS, via overexpression of superoxide dismutase (SOD1 or SOD2 product), not only greatly extends the life span of this mutant but also increases its ability to respire. Another ATD mutant with similarly reduced respiration (rpo41-D152A/D154A) accumulates only intermediate levels of ROS and has a less severe life span defect that is not rescued by SOD. Altogether, our results provide compelling evidence for the “vicious cycle” of mitochondrial ROS production and lead us to propose that the amount of ROS generated depends on the precise nature of the mitochondrial gene expression defect and initiates a downward spiral of oxidative stress only if a critical threshold is crossed.
MR angiography of aberrant left subclavian artery arising from right-sided thoracic aortic arch

Right-sided thoracic aortic arch with aberrant left subclavian artery is an uncommon entity that is usually asymptomatic, but may present in adults with symptoms of dysphagia. Cross-sectional imaging such as CT or MR is often required to conclusively diagnose this condition, which may be suggested by chest radiograph or barium swallow. MRI including TRICKS (time-resolved imaging of contrast kinetics) magnetic resonance angiography (MRA) was utilized in the evaluation of a 40-year-old man presenting with dysphagia and abnormal barium swallow study. TRICKS MRA is a recently developed MRA technique, which can provide multiple high-resolution images of the thoracic vessels with a high temporal resolution without the need for timing doses of gadolinium contrast or multiple injections.
Disassembly Sequence Evaluation: A User Study Leveraging Immersive Computing Technologies

As interest in product recovery, reuse, and recycling rises, planning and evaluating disassembly sequences are becoming increasingly important. The manner in which a product can be taken apart strongly influences end-of-life (EOL) operations and costs. Early disassembly planning can also inform non-EOL processes including repair and routine maintenance. Recently, research has concentrated on creating optimization algorithms which automatically generate disassembly sequences. These algorithms often require data that are unavailable or estimated with high uncertainty. Furthermore, industries often employ CAD modeling software to evaluate disassembly sequences during the design stage. The combination of these methods result in mathematically generated solutions, however, the solutions may not account for attributes that are difficult to quantify (human interaction). To help designers better explore and understand disassembly sequence opportunities, the research presented in this paper combines the value of mathematical modeling with the benefits of immersive computing technologies (ICT) to aid in early design decision making. For the purposes of this research, an ICT application was developed. The application displays both 3D geometry of a product and an interactive graph visualization of existing disassembly sequences. The user can naturally interact with the geometric models and explore sequences outlined in the graph visualization. The calculated optimal path can be highlighted allowing the user to quickly compare the optimal sequence against alternatives. The application has been implemented in a three wall immersive projection environment. A user study involving a hydraulic pump assembly was conducted. The results suggest that this approach may be a viable method of evaluating disassembly sequences early in design. [DOI: 10.1115/1.4028857]
Organometallic polymers. XXIV. Synthesis and copolymerization behavior of h6-(2-phenylethyl acrylate) tricarbonylchromium

The monomer h6-(2-phenylethyl Acrylate) tricarbonylchromium (PEAC) was synthesized and copolymerized in solution at 70°C with styrene, methyl acrylate, acrylonitrile, and 2-phenylethyl acrylate, azobisisobutyronitrile being used as the initiator. In ethyl acetate solvent the relative reactivity ratios were crudely approximated. The copolymers all exhibited binodal molecular weight distributions, the high molecular weight node probably resulting from branching. The h6-benzenetricarbonylchromium unit decomposed when exposed to sunlight or ultraviolet light both in air and under N2. In air, Cr2O3 was initially formed within copolymer films. Several unsuccessful attempts were made to prepare h6-(2-phenylethyl acrylate)tricarbonylmolybdenum, (III), the molybdenum analog of PEAC, from arenes and both Mo(CO)6 and (CH3CN)3Mo(CO)3. These reactions are described.