cssi/SciSciGPT-SciSciNet huggingface dataset:
Cytochrome p450 2E1 in rat tracheobronchial airways : Response to ozone exposure

The distal trachea and centriacinus of the lung are primary sites of acute injury during short-term ozone exposure; long-term exposure yields cells in these areas that are resistant to high doses of oxidant gases. Epithelial cells located in primary sites for ozone injury are also targets for chemicals that undergo cytochrome P450 (CYP)-dependent activation. These studies were designed to compare the effects of ozone exposure on pulmonary CYP2E1 in susceptible and nonsusceptible sites within the airway tree of lung. CYP2E1 activity was measured in well-defined regions of airways using p-nitrophenol, a CYP2E1-selective substrate, with HPLC/ electrochemical detection of the p-nitrocatechol. Alterations in distribution of CYP2E1 were evaluated by immunohistochemistry. CYP2E1 activities were highest in the distal bronchioles and minor daughter airways but were much lower in the lobar bronchi/ major daughter airways and trachea. Immediately after short-term ozone exposures (8 h, 1 ppm), CYP2E1 activities were elevated only in the lobar bronchi/major daughter airways. These activities remained above the filtered air control at 1 day but returned to control levels by 2 days. Immunohistochemical assessment of CYP2E1 protein in ozone and filtered air-exposed animals was consistent with the activity measurements. After long-term ozone exposures (90 days, 1 ppm), CYP2E1 activities were decreased in the major and minor daughter airways. These studies indicate that CYP2E1 activities vary substantially by airway level. However, ozone exposure only results in minimal alterations in activity with varying concentration of ozone, length of exposure, and time after exposure in any of the lung subcompartments examined.
Fatigued breast cancer survivors: The role of sleep quality, depressed mood, stage and age

Cancer-related fatigue is associated with lower health-related quality of life and the majority of breast cancer survivors experience persistent fatigue after finishing treatment. The present study examines age, cancer stage, sleep quality and depressed mood as predictors of five dimensions of fatigue in 70 fatigued breast cancer survivors who no longer evidenced any signs of cancer and were finished with treatment. Discriminant function analyses were used to predict fatigue subgroup membership (higher, lower) from age, stage, mood and sleep for five subtypes: General, Mental, Emotional, and Physical fatigue, and Vigour. Significant discriminant functions were found for all subtypes. Findings suggest that age, staging, mood and sleep are all important predictors, but there are differential relationships when subtypes of fatigue are considered. Given current limitations in treating fatigue directly, interventions targeting mood and sleep should be considered as alternate approaches to reduce fatigue.
The energy and the linear momentum of space-times in general relativity

We extend our previous proof of the positive mass conjecture to allow a more general asymptotic condition proposed by York. Hence we are able to prove that for an isolated physical system, the energy momentum four vector is a future timelike vector unless the system is trivial. Furthermore, we allow singularities of the type of black holes.
MO-D-I-611-04: Region-Of-Interest (ROI) Computed Tomography: Combining Dual Resolution XRII Images

Purpose: High‐resolution computed tomographic systems can require large radiation dose for full‐field‐of‐view (FFOV) reconstructions. We have developed a method for obtaining data inside an ROI at high‐dose and high‐resolution and combining it with low‐dose, low‐resolution data outside the ROI. The combined image is reconstructed to obtain improved image quality both inside and outside the ROI but at reduced integral dose. Method and Materials: Projection images of a head phantom were obtained using the 5″ and 12″ modes of an x‐ray image intensifier. The 5″ mode effectively defined an ROI and the 12″ mode encompassed the whole object (i.e., FFOV), but at 1/4 the dose of the 5″ mode. The 5″ and 12″ projection images were aligned and combined. Since the data outside the ROI was obtained at a lower dose, the intensity inside and outside the ROI in the combined image was equalized prior to backprojection. The mapping function was determined, using the pixels lying just inside and outside the ROI. A second approach was simulated by assigning the average pixel value in the ROI to all pixels outside the ROI. Both cases were reconstructed using a Feldkamp cone‐beam algorithm. Results: For both cases, we obtained reconstruction comparable to FFOV reconstruction inside the ROI. However, the combined image produced a reconstructed image comparable to the FFOV reconstruction outside the ROI as well. Moreover, the resolution of the region inside the ROI in the reconstructed image was determined by the 5″ mode as opposed to the 12″ mode. Conclusion: ROI CT using two sets of data provides a way to reconstruct an ROI with greatly reduced integral dose and artifacts and yet improved spatial resolution. Supported by: NIH R01NS38746, R01NS43924, R01HL52567, R01EB002916, and R01EB002873 and the Toshiba Medical Systems Corporation).
Bacterial glycoconjugates are natural ligands for the carbohydrate binding site of discoidin I and influence its cellular compartmentalization

Abstract Klebsiella pneumoniae, Escherichia coli, and Bacillus subtilis, bacteria commonly eaten by Dictyostelium discoideum, contain glycoconjugates that bind discoidin I, a lectin synthesized by the slime mold as it differentiates. In cells fed bacteria that contain abundant discoidin I-binding glycoconjugates, these ligands and endogenous discoidin I accumulated in specialized structures called multilamellar bodies. In contrast, in cells fed bacteria that had been treated to thoroughly deplete them of discoidin I-binding glycoconjugates, neither endogenous discoidin I nor complementary glycoconjugates were found in the multilamellar bodies. In such cells discoidin I was located in the cytoplasm, as indicated by both immunohistochemistry with the electron microscope and immunoassay of subcellular fractions. The results indicate that a function of the carbohydrate-binding site of discoidin I is to interact with bacterial glycoconjugates, which the slime mold does not degrade. This interaction directs compartmentalization of the lectin in multilamellar bodies and its externalization from the cell in these structures.
Historicizing and Contextualizing the Discourse on African International Law and A Concise Overview of the Pacific Settlement of the Cameroon-Nigeria Bakassi Peninsula Dispute

For the past 50 years or so, the media and intellectual discourses on African politics have general portrayed the continent as being in perpetual turmoil. Th e causes of such conflicts have been related, but not limited, to the outcome of the Berlin Conference of 1884-85 in which some of the European powers carved up the region in a zigzag fashion with little or no concern for the ethnic complexions of the societies. Th e result of this policy in post-colonial and independent Africa has been disastrous for much of the continent with numerous civil wars and cross border clashes between African states. Th e use of arms struggle to resolve border conflicts is now seen as counter productive to the vision of African unity and transformation in the millennium as first articulated by the Organization of African Unity and now championed by the African Union – the successor to the OAU. Th is study brings into the limelight the extent to which African states are increasingly relying on international law, the AU and the Good Offices of the UN and its various agencies to resolve international boundary conflicts. It also historicized the development of international law in Africa and discussed as a case study the impressive pacific settlement of the explosive border dispute between Cameroon and Nigeria to illustrate its importance as a model for Africa.
Biological rationale and clinical experience with hyperthermia.

Hyperthermia (HT) as an adjunct to radiation therapy (RT) has been a focus of interest in cancer management in recent years there have been numerous randomized and nonrandomized studies conducted to assess the efficacy of HT combined with either RT or chemotherapy especially in the treatment of superficially seated malignant tumors. The major impact of HT is currently on locoregional control of tumor. Heat may be directly cytotoxic to tumor cells or inhibit repair of both sublethal and potentially lethal damage after radiation. These effects are augmented by the physiological conditions in tumor that lead to states of acidosis and hypoxia. Blood flow is often impaired in tumor relative to normal tissues, and HT may lead to a further decrease in blood flow and augment heat sensitivity. Three major areas of clinical investigation have borne the greatest fruit for HT as adjunctive therapy to RT. These include recurrent and primary breast lesions, melanoma, and head and neck neoplasms. Thermal enhancement ratio was increased in all cases and is approximately 1.4 for neck nodes, 1.5 for breast, and 2 for malignant melanoma. In general, the most important prognostic factors for complete response (CR) are RT dose, tumor size and minimal thermal parameters minimal thermal dose (t43min), mean minimal temperature (Tmin) or T90, i.e., temperature exceeded by 90% of thermal sensors]. The number of HT fractions administered per week appears to have no bearing on the overall response, which may be indicative of the effects of thermotolerance. The total number of HT fractions delivered also appears irrelevant provided adequate HT is delivered in one or two sessions. The major prognostic factors for the duration of local control were tumor histology, concurrent RT dose, tumor depth and Tmin. Although numerous single institution studies showed increased CR rates and improved local control, the efficacy of HT as an adjunct to RT should be assessed with well-designed multi-institutional randomized clinical trials. Such clinical trials are underway.
Optimizing RAM-latency dominated applications

Many apparently CPU-limited programs are actually bottlenecked by RAM fetch latency, often because they follow pointer chains in working sets that are much bigger than the CPU's on-chip cache. For example, garbage collectors that identify live objects by tracing inter-object pointers can spend much of their time stalling due to RAM fetches.We observe that for such workloads, programmers should view RAM much as they view disk. The two situations share not just high access latency, but also a common set of approaches to coping with that latency. Relatively general-purpose techniques such as batching, sorting, and "I/O" concurrency work to hide RAM latency much as they do for disk.This paper studies several RAM-latency dominated programs and shows how we apply general-purpose approaches to hide RAM latency. The evaluation shows that these optimizations improve performance by a factor of 1.3x. Counter-intuitively, even though these programs are not limited by CPU cycles, we found that adding more cores can yield better performance.
Ontogenetic changes in the extra-pituitary expression of pro-opiomelanocortin in the developing ovine fetus.

Previous studies performed in this laboratory have demonstrated that the fetal lung contains immunoreactive adrenocorticotropin (irACTH), and that the lung both clears and secretes irACTH under basal and stimulated conditions. Furthermore, we have demonstrated that the irACTH in fetal lung is accounted for by proopiomelanocortin (POMC), and that there is an evidence of post-translational processing that is distinct from the pattern of processing typical of the anterior pituitary. The present study was designed to test the hypothesis that POMC is synthesized in the fetal lung, and that there is decreased synthesis in the late-gestation ovine fetal lung. Lungs were collected from fetal sheep at 80, 100, 120, 130, and 145 days gestation (n = 4/group; term = 147 days). POMC mRNA was measured using reverse transcription and real-time polymerase chain reaction with probe and primers designed in this laboratory. The greatest abundance of POMC mRNA was in the 80-days fetal sheep, and the relative abundance decreased as a function of fetal gestational age. POMC protein was measured using immunoblot analysis in lungs from 80, 120, and 145-days fetal sheep. The pattern of POMC protein abundance was consistent with that of the mRNA (highest at 80 days, lowest at 145 days). The POMC immunoblot revealed specific staining of a peptide with molecular weight of 27 kDa and another peptide with a molecular weight slightly higher than that of native POMC (32 kDa). For comparison, we measured POMC mRNA in skeletal muscle and small intestine. We found POMC expression in both fetal tissues, but no statistically significant ontogenetic pattern of expression. We conclude that POMC is synthesized in the ovine fetal lung, and that the rate of synthesis decreases as the fetus matures in utero. We speculate that the decreasing abundance of POMC mRNA and protein reflects decreased release of POMC and POMC-related peptides into the fetal bloodstream.
Entropy and diminishing elasticity of substitution

Abstract In the debate over sustainable development and limits to growth, one critical issue has to do with substitutability. ‘Weak’ sustainability as the ability to maintain a generalized capacity to produce is described by Pearce, D.W., Atkinson, G.D., Dubourg, W.R., 1994. The economics of sustainable development. In: Socolow, R.H. (Ed.), Annual Review of Energy and the Environment, vol. 19, 457–474. Weak sustainability can occur in the face of a non-renewable, non-recyclable, essential resource if the economy can substitute capital for the essential resource is shown theoretically in Solow, R.M., 1974. Intergenerational equity and exhaustible resources. Review of Economic Studies, Symposium on the Economics of Exhaustible Resources, pp. 29–45; Hartwick, J.M., 1977. Intergenerational equity and the investing of rents from exhaustible resources. American Economic Review 67(5), 972–974; Dasgupta, P.S., Heal, G.M., 1979. Economic Theory and Exhaustible Resources, Cambridge University Press, Cambridge, 196–207. However, the analyses depend on a Cobb-Douglas production function with a constant elasticity of substitution out to infinity. This paper shows that a Cobb-Douglas function eventually violates entropy and that the elasticity of substitution between any two inputs must at some point become zero. Different types of substitution are examined to show how physics and the law of entropy cause the elasticity of substitution to decline.
Electron microscopy study of a rejuvenated vehicle-aged automotive exhaust catalyst

Abstract Electron probe microanalysis (EPMA) and analytical electron microscopy (AEM) were used to characterize the changes that occur on a vehicle-aged three-way automotive catalyst as a result of two rejuvenation treatments. One treatment involves washing a catalyst with an aqueous solution of oxalic acid followed by calcination. This treatment results in the redistribution of phosphorus- and lead-based poison deposits, but leaves silicon- and sulfur-containing species in place. Noble metal radial profiles within the catalyst appear to be unaffected. Some evidence was found that this washing treatment may reverse the segregation of Pd in multimetallic Pt/Pd particles. The second treatment involves the redispersion of the noble metals by a high-temperature chlorination. This process has little effect on poison or noble metal radial distributions within the catalyst pellet. However, substantial reduction in the noble metal particle size was observed; particle size distributions which are comparable to those observed on fresh catalysts were produced by this treatment. The redispersed noble metal particles were generally multimetallic, indicating little bulk separation of the noble metals from the multimetallic particles originally present on the aged catalyst.
Leukotriene inhibition prevents and reverses hypoxic pulmonary vasoconstriction in newborn lambs.

ABSTRACT: The effects of the leukotriene antagonist FPL 57231 on the circulation were studied in spontaneously breathing normoxic and hypoxic newborn lambs in order to evaluate the role of leukotrienes in the perinatal control of hypoxic pulmonary vasoconstriction. Hypoxia produced a 58% increase in pulmonary arterial pressure (p < 0.05) and a 37% increase in pulmonary vascular resistance (p < 0.05). Hypoxic pulmonary vasoconstriction was abolished by the prior infusion of FPL 57231. Pulmonary arterial pressure increased by only 8% and pulmonary vascular resistance decreased by 10% from normoxia. The infusion of FPL 57231 during hypoxia-induced pulmonary vasoconstriction reversed the increase in pulmonary arterial pressure (p < 0.05) and pulmonary vascular resistance (p < 0.05). The hypoxia-induced increase in cardiac output was maintained during the infusion of FPL 57231. Leukotrienes may play a significant role in the mediation of hypoxic pulmonary vasoconstriction. Leukotriene inhibition with FPL 57231 may be useful in the management of infants with persistent pulmonary hypertension syndrome.
An x-ray fluorescence spectroscopic method for the determination of total manganese in rocks and marine sediments

Abstract A method for the determination of manganese by X-ray fluorescence is described. By using scattered X-rays as an internal standard, a linear calibration plot is obtained for standard rocks that agrees with the chemical data. The scattered X-ray method, compared with a widely used net-intensity method, shows improvement in accuracy especially at higher concentrations.
Periodic Markets: A Problem In Locational Analysis1

(1972). Periodic Markets: A Problem In Locational Analysis. The Professional Geographer: Vol. 24, No. 3, pp. 210-216.
Economic implications of proposed accounting for stock-based compensation

This article examines the market expectations of the proposed accounting changes for stock-based compensation in the exposure draft that preceded the Statement of Financial Accounting Standards No. 123. The exposure draft made recommendations that significantly differed from current practice. Affected firms expressed concern that the proposed changes would drastically reduce their reported earnings. This could lead to firms becoming less attractive to capital sources (resulting in higher costs of capital) and firms refraining from using stock options to attract talented managers and entrepreneurs. The market test shows that affected firms experienced negative security market prices contemporaneous with issuance of the exposure draft. Cross-sectional analyses indicate that the magnitude of price decline is associated with measures of high risk and less mature firms.
Tissue Refractive Index as a New Imaging Parameter for Diffuse Optical Tomography: Pilot Results in the Breast

We describe an extension of diffuse optical tomography (DOT) technique for imaging phase-contrast due to the spatial variation of tissue refractive index. We demonstrate this phase-contrast DOT using pilot clinical data for breast cancer detection.
Direct correlation method for OH, NH and CH local modes: vibrational overtone spectroscopy of biphenyl, anthracene, isobutanol, 2-chloroethanol and ethylenediamine at the third overtone region

Abstract The vibrational overtone spectra of gaseous biphenyl, anthracene, isobutanol, 2-chloroethanol and ethylenediamine at the Δv=4 vibrational overtone region have been recorded and assigned using the local mode model. For the spectral assignments, linear correlations were determined between the ab initio bond lengths (calculated in this work) and the overtone transition energies (taken from the literature) of aromatic and nonaromatic hydrocarbons, alcohols and amines. The bond lengths were obtained from ab initio geometry optimizations using both the 3-21G * and the 6-31G ** basis sets. The bond length–overtone transition wavenumber correlations for the OH, NH and aromatic, methyl and methylenic CH oscillators are presented for the Δv=4 region for both basis sets. The bond lengths (CH for biphenyl and anthracene, OH for isobutanol and 2-chloroethanol and NH for ethylenediamine) were also determined. These bond lengths were used to predict the transition wavenumbers for Δv=4 transitions which could then be compared to the experimental values. These predictions which accounted for the possibility of various conformations agreed well with the experiment.
Production of hydrocarbon fuels from biomass using catalytic pyrolysis under helium and hydrogen environments

This study is focused on hydrocarbon production through changing carrier gas and using zeolite catalysts during pyrolysis. A large reduction in high molecular weight, oxygenated compounds was noticed when the carrier gas was changed from helium to hydrogen during pyrolysis. A catalytic pyrolysis was conducted using two different methods based on how the biomass and catalysts were contacted together. For both methods, there was no significant change in the carbon yield with the change in pyrolysis environment. However, the mixing-method produced higher aromatic hydrocarbons than the bed-method. In addition, two methods were also tested using two ratios of biomass to catalyst. Nonetheless, there was no significant increase in hydrocarbon yield as the catalyst loading was increased from two to five times of biomass in the catalyst-bed method. In contrast to this, a significant increase was noticed for the catalytic-mixing method when the biomass to catalyst loading was increased from 1:4 to 1:9.
Kinetic Trends in RAFT Homopolymerization from Online Monitoring

Automatic continuous online monitoring of polymerization reactions (ACOMP) was used to follow kinetic trends in the reversible addition -fragmentation chain transfer (RAFT) polymerization of butyl acrylate (BA) in butyl acetate, using 2-{((dodecylsulfanyl)carbonothioyl)sulfanyl}propanoic acid (DoPAT) as the RAFT agent and 2,2-azobis(isobutyronitrile) as the initiator (AIBN). The goals were to demonstrate the use of ACOMP for RAFT studies and to examine the trend in conversion and evolution of weight-average molar mass Mw and weight-average intrinsic viscosity ( )w for a series of experiments in which the RAFT agent concentration was decreased over a wide range while all the other reaction conditions were held constant; (DOPAT)/(AIBN) ranged from 0 to 2.4. This allowed monitoring the transition from "living"-like behavior in the "controlled radical polymerization" (CRP) regime, where sufficient RAFT agent was used, to the noncontrolled radical polymerization regime as RAFT agent was progressively reduced to zero. The conversion kinetics were found to be essentially zeroeth order in DoPAT, and deviations from living behavior allowed estimates of radical efficiency. The evolution of Mw vs monomer conversion varied dramatically from near-ideal living behavior at high (DoPAT)/(AIBN) to classical radical polymerization behavior at (DoPAT) ) 0. All but one experiment showed a nonzero Mw at f ) 0, and the conversion behavior of Mw points to transfer and branching side reactions, depending on (DoPAT). ACOMP should prove to be a useful tool both for fundamental RAFT research and process development.
Psychological and Sensory Predictors of Experimental Thermal Pain: A Multifactorial Model

Abstract Although large interindividual differences in pain exist, the underlying factors that contribute to these variations remain poorly understood. Consequently, being able to accurately explain variability in pain ratings in terms of its contributing factors could provide insights into developing a better understanding of individual differences in pain experience. In the present investigation, we show that a significant portion of the variability in experimental heat pain ratings may be predicted using simple quantitative sensory testing and a series of psychological questionnaires including State Trait and Anxiety Inventory (STAI), Center for Epidemiologic Studies – Depression Scale (CES-D), and Positive and Negative Affect Schedule – Expanded form (PANAS-X). A factor analysis was used to reduce individual predictors into sets of composite predictive factors. A multifactorial model that was generated from these factors can reliably predict a significant amount of the variability in heat pain sensitivity ratings ( r 2 = .537, P = .027). Moreover, individual variables including heat pain thresholds and self-assessment of pain sensitivity were found to be poor predictors of heat pain sensitivity. Taken together, these results suggest that a variety of factors underlie individual differences in pain experience and that a reliable model for predicting pain should be constructed from a combination of these factors. Perspective The present study provides a way to predict subjects' experimental heat pain sensitivity using a multifactorial model generated from a combination of sensory and psychological factors. Future application of such a model in the studies of clinical pain could potentially improve the quality of care provided for patients in pain.
Practical problems in using job evaluation systems to determine compensation

Since job evaluations have historically provided a primary basis for compensation, it is easy to accept them unquestioningly as a starting point for compensation determination. But job evaluations suffer from inherent problems, they are often misused, and they are fundamentally incompatible with many innovative managerial approaches. This article highlights many of these practical problems in using job evaluations and urges their critical examination prior to their adoption and use.
Computation of Mach reflection from rigid and yielding surfaces

The present discussion centers on a theoretical description of one aspect of the irregular or Mach reflection from solid surfaces. The discussion is restricted to analytical considerations and some preliminary results using model approximations to the surface interaction phenomena. Currently, full numerical simulations of the irregular reflection surface interaction dynamics have not been obtained since the method is still under development. Discussion of the numerical method is, therefore, restricted to some special procedures for the gas-solid surface boundary dynamics. The discussion is divided into an introductory section briefly describing a particular Mach reflection process. Subsequently, some of the considerations on boundary conditions are submitted for numerical treatment of the gas-solid interface. Analysis and discussion of a yielding solid surface subjected to impulsive loading from an intense gas shock wave follows. This is used as a guide for the development of the numerical procedure. Mach reflection processes are then briefly reviewed with special attention for similitude and singular perturbation features.
Upper airway obstruction from foregut cysts of the hypopharynx.

T HIS REPORT describes experiences with upper airway obstruction in three neonates caused by cysts of foregut origin within the hypopharynx. Foregut cysts, including esophageal duplications and bronchogenic cysts, have been reported in this location extremely rarely but have not been associated with airway obstruction. Is2 Each of these cases required emergency establishment of an airway before dealing with the lesion.
Comparison of the FryLess 100 K Radiant Fryer to oil immersion frying

With limited success, numerous attempts have been made to reduce the fat content of oil immersion fried foods, while maintaining their unique characteristics. A recent advancement in frying is dynamic radiant frying. Radiant frying utilizes infrared energy to reproduce the heating profile generated during oil immersion frying without oil immersion. The result being a fried food with a crispy surface and similar temperature profile to immersion fried with significantly less oil. The goal of this study was to compare frozen, consumer-ready chicken patties, fried using the FryLess 100 K Radiant Fryer, and oil immersion frying, respectively. Properties compared included core and surface temperatures, oil content, moisture content, color, and peak shear force. Significant differences (P < 0.01) were observed in color, oil content, and moisture content. Radiant fried patties were slightly lighter in color and had an average of 16% less oil and 19% more moisture than the immersion fried. Sensory evaluation revealed that panelists preferred the flavor and less oily mouthfeel of the radiant fried patties, but preferred the crispness and appearance of the immersion fried patties. Panelists indicated no difference in overall preference signifying that radiant frying may serve as a viable alternative to oil immersion frying of some chicken products.
School Phobia and Separation Anxiety: Diagnostic and Treatment Comparisons.

There exists substantial confusion regarding the comparative diagnostic criteria and treatment implications for school phobia and separation anxiety. A literature survey demonstrates the tendency of school personnel to put all youngsters exhibiting these disorders into one group called “school refusers.” Treatment issues are handled in a similar fashion despite accumulating evidence of treatment-relevant differences between the disorders. Variables that facilitate a finer diagnostic discrimination are presented. After reviewing pertinent treatment distinctions between the two disorders, specific behaviorally oriented methods are recommended.
School Desegregation and Black Assimilation

Many changes in American race relations have occurred in the three decades since the Brown v. Board of Education decision. Some of these changes are related to school desegregation and have been extensively studied—e.g., changes in racial attitudes among both blacks and whites, and changes in black self-esteem and achievement-test performance. In contrast, relatively little is known about the long-term effects of school desegregation on assimilation—full and equal participation of blacks in the social, economic, and political life of the society. When school desegregation is viewed in the context of the long-term functions of education, it seems important for researchers and policy makers to ask whether it promotes the social integration of blacks and whites in adult life and enhances the career attainments of blacks. These important issues have recently begun to receive empirical research attention. This article reviews recent research on the long-term effects of school desegregation on black assimilation, emphasizing evidence from several national surveys. Implications for social policy, intergroup relations, and interracial equity are discussed.
Real-time multilevel process monitoring and control of CR image acquisition and preprocessing for PACS and ICU

The purpose of this paper is to present a control theory and a fault tolerance algorithm developed for real time monitoring and control of acquisition and preprocessing of computed radiographs for PACS and Intensive Care Unit operations. This monitoring and control system uses the event-driven, multilevel processing approach to remove computational bottleneck and to improve system reliability. Its computational performance and processing reliability are evaluated and compared with those of the traditional, single level processing approach.
Algorithms for Circuits and Circuits for Algorithms

The title of this paper is meant to highlight an emerging duality between two fundamental topics in algorithms and complexity theory. Algorithms for circuits} refers to the design of interesting algorithms which can perform non-trivial circuit analysis of some kind, on either a circuit or a Boolean function given as a truth table. For instance, an algorithm determining whether a given circuit has an input that forces a true output would solve the NP-complete Circuit-SAT problem. Such an algorithm is of course unlikely to run in polynomial time, but could possibly be more efficient than exhaustively trying all possible inputs to the circuit. Circuits for algorithms refers to the modeling of uniform algorithms with non-uniform circuit families (or proving such modeling is impossible). For instance, the NEXP versus P/poly question asks whether nondeterministic exponential-time algorithms can be simulated using non-uniform circuit families of polynomial size. It is widely believed that the answer is emph{no}, however the present mathematical tools available are still too crude to prove this kind of separation. This paper surveys these two generic subjects, the ways in which they arise, and connections that have been developed between them, focusing on the connections between non-trivial circuit-analysis algorithms and proofs of circuit size lower bounds. To give one example, if there is a nontrivial algorithm (running slightly faster than exhaustive search) that can determine if a given circuit computes a constant function, then it can be concluded that NEXP is not contained in P/poly. Informally, this connection can be interpreted as saying "some good algorithms for circuits imply there are no good circuits for some algorithms."
Characterization of the NAD(P)H Oxidase and Metronidazole Reductase Activities of the RdxA Nitroreductase of Helicobacter pylori

Metronidazole (MTZ) is widely used in combination therapies against the human gastric pathogen Helicobacter pylori. Resistance to this drug is common among clinical isolates and results from loss-of-function mutations in rdxA, which encodes an oxygen-insensitive nitroreductase. The RdxA-associated MTZ-reductase activity of H. pylori is lost upon cell disruption. Here we provide a mechanistic explanation for this phenomenon. Under aerobic conditions, His6-tagged RdxA protein (purified from Escherichia coli), catalyzed NAD(P)H-dependent reductions of nitroaromatic and quinone substrates including nitrofurazone, nitrofurantoin, furazolidone, CB1954 and 1,4-benzoquinone, but not MTZ. Unlike other nitroreductases, His6-RdxA exhibited potent NAD(P)H-oxidase activity (k(cat) = 2.8 s(-1)) which suggested two possible explanations for the role of oxygen in MTZ reduction: (a) NAD(P)H-oxidase activity promotes cellular hypoxia (nonspecific reduction of MTZ), and (b) molecular oxygen out-competes MTZ for reducing equivalents. The first hypothesis was eliminated upon finding that rdxA expression, although increasing MTZ toxicity in both E. coli and H. pylori constructs, did not increase paraquat toxicity, even though both are of similar redox potential. The second hypothesis was confirmed by demonstrating NAD(P)H-dependent MTZ-reductase activity (apparent K(m) = 122 +/- 58 microM, k(cat) = 0.24 s(-1)) under strictly anaerobic conditions. The MTZ-reductase activity of RdxA was 60 times greater than for NfsB (E. coli NTR), but 10 times lower than the NADPH-oxidase activity. Whether molecular oxygen directly competes with MTZ or alters the redox state of the FMN cofactors is discussed.
Multicilin promotes centriole assembly and ciliogenesis during multiciliate cell differentiation

Several specialized cell types assemble hundreds of motile cilia to accomplish their function. Kintner and colleagues identify the coiled-coil protein multicilin as an essential regulator of multicilia formation in Xenopus skin and the mammalian kidney. Their data indicate that multicilin activates the transcription of genes required for multicilia formation, including the transcription factor Foxj1.
New laboratory techniques for hospital infection control

The clinical microbiologist has important responsibilities in hospital infection control. Duties include participating in hospital-wide infection control activities (especially the infection control committee), recovering and identifying accurately the organisms responsible for nosocomial infection, characterizing antimicrobial susceptibility of many of these nosocomial pathogens, reporting in timely fashion laboratory data relevant to infection control, carrying out the few routine microbiologic studies of the hospital environment that are useful, supporting investigations of specific hospital infection problems as they arise, and providing special typing studies when necessary to establish similarity or difference of organisms. In the past decade, improvements in laboratory instrumentation and/or procedures have provided dramatic help to infection control efforts in several of these areas. Among these are new techniques for more rapid detection and differentiation of organisms and improved systems of reporting for both patient data and trend analysis. Perhaps the most dramatic advances have come in special procedures for examining (typing) hospital organisms for similarity or difference; here, molecular and other techniques have permitted more definitive examination of a wider range of organisms than previously was possible. With health care resources in the United States now at a premium, the current and future challenge for laboratories is to make their participation in infection control more efficient as well as effective. Establishing adequate quality control of methods and obtaining clinical data to allow correct interpretation will be crucial for efficient use of the new typing procedures. Deciding when these techniques are needed and whether they should be performed on site also will be an important part of this process.
Design of blood pressure screening for clinical trials of hypertension

Abstract In clinical trials of hypertension the eligibility of a subject is usually determined at a series of screening visits prior to randomization. Only those subjects whose blood pressures are within certain limits at each of specified visits are eligible. The pressure measurement of any individual has considerable time-to-time variability, therefore subjects who have passed one screen may ‘regress towards the mean’ and not pass subsequent screens. This paper is a statistical examination of the effect of different numbers of screens and pressure limits on the probability of a given subjects passing all screens, the proportion of subjects who pass, and the distribution of their blood pressures. Numerical estimates, using data from the literature, indicate that the best way to maximize yield while controlling the distribution of blood pressures of selected subjects is to have several screens with pressure limits slightly wider than the goal.
Intra-uterine Treatment of a Hypothyroid Fetus

A woman in her 24th week of gestation was referred for treatment of hypothyroidism, after she underwent radioablation of the thyroid during the 13th week of gestation. Because of the high risk of hypothyroidism in the fetus, prenatal administration of intramuscular T4 to the fetus was begun at 32 weeks. The last dose of T4 was given 2 weeks before delivery; cord blood levels of T4 and T3 were undetectable and the TSH concentration was markedly elevated. The case illustrates several important physiological concepts regarding thyroid hormone and TSH metabolism in the fetalplacental unit, including the minimal placental permeability to iodothyronines and TSH, independent function (including feedback control) of the fetal hypothalamic-pituitary-thyroid axis, and the TSH response at parturition. In addition we suggest that administration of T4 to the hypothyroid fetus in utero is an acceptable modality of treatment and may help to minimize irreversible mental retardation in known high risk infants. However, fu...
A Model of the Firm’s Sources of Experiential Knowledge in the Internationalization Process

In this theoretical chapter, I develop a model of the firm’s sources of experiential knowledge in the internationalization process based on knowledge-based theory (KBT). In order to do so, I begin by briefly reviewing the KBT literature (Eisenhardt & Santos, 2002; Grant, 1996a, 1996b), explaining how it applies to the internationalization literature (Barkema & Drogendijk, 2007; Johanson & Vahlne, 1977, 1990) and finally bringing these ideas together to examine the mechanisms and sources of knowledge transfer in the internationalization process.
Angiotensin II evokes sensory long-term facilitation of the carotid body via NADPH oxidase

We previously reported that reactive oxygen species generated by NADPH oxidase 2 (Nox2) induces sensory plasticity of the carotid body, manifested as a progressive increase in baseline sensory acti...
Many-body conjugated-circuit computations

A powerful algorithm for calculating conjugated-circuit expectations for planar graphs is enunicated. The utility for systematizing quantitative resonance-theoretic computations on conjugated hydrocarbons, and related species, is emphasized.
Effects of simultaneous application of opposing brain-stem stimuli on respiration and blood pressure in anesthetized cats

Abstract The effect of simultaneous stimulation of paired brain-stem sites, one of which elicited an increase and the other a decrease in respiration or in blood pressure, was assessed in cats anesthetized with Nembutal or chloralose. Sites of stimulation were dispersed from posterior hypothalamus to medulla oblongata. Under Nembutal anesthesia, alterations of respiratory amplitude or rate in opposite directions were found upon single stimulation of sixteen pairs of sites. Simultaneous stimulation of these paired opposing sites yielded the following patterns in terms of respiration: (a) algebraic summation or cancellation of opposing effects; (b) a response equivalent to that seen upon stimulation of one site of the pair, representing simple dominance; or (c) a response of markedly greater magnitude than that seen upon single stimulation, representing exaggeration. Under chloralose anesthesia, eleven pairs of sites exerted opposing effects on blood pressure, and eight of these pairs also altered respiratory rate in opposite directions. Simultaneous stimulation resulted in either (a) algebraic summation or (b) an exaggerated response; simple dominance was not observed in cats anesthetized with chloralose. An exaggerated response in one function (e.g., blood pressure) was usually accompanied by an algebraic summation of the other (e.g., respiration). Thus the functions of blood pressure and respiration are capable of exhibiting several types of response to simultaneous opposing stimuli, when sites of stimulation are dispersed through several areas of the brain stem in anesthetized cats. The two functions may reveal independence in their patterns of response to simultaneous stimulation of the same pair of brain-stem areas.
Civic Culture and Urban Discourse, a Rejoinder

(1996). Civic Culture and Urban Discourse, a Rejoinder. Journal of Urban Affairs: Vol. 18, No. 3, pp. 241-243.
Surgeon Perceptions of Natural Orifice Translumenal Endoscopic Surgery (NOTES)

If proven feasible and safe, Natural Orifice Translumenal Endoscopic Surgery (NOTES) would still need acceptance by surgeons if it were to become a mainstream approach. Three hundred fifty-seven surgeons responded to a preliminary survey describing NOTES and were asked to rate the importance of various surgical considerations and (assuming availability and safety) if they would choose to undergo and/or perform cholecystectomies by NOTES or laparoscopy and why. The risk of having a complication was considered most important. NOTES was theorized to be riskier and to require greater skill than laparoscopy but to potentially cause less pain and convalescence. Nearly three-fourths (72%) of surgeons expressed interest in NOTES training which correlated with younger age, SAGES membership, minimally invasive surgery specialization, and flexible endoscopic volume. Forty-four percent would like to introduce NOTES cholecystectomy into their practices. Among those not preferring NOTES, 88% would adopt NOTES if data showed improved outcomes over laparoscopy. Finally, only 24% would choose to undergo cholecystectomy themselves by NOTES, believing it to be too new and riskier than laparoscopy. The risk of having a complication is the greatest concern among surgeons, and safety will affect NOTES acceptance. The results of this survey seem to justify more focused future investigations.
Immune regulation and HLA types in chronic hepatitis.

Studies were undertaken in 32 patients with hepatitis B-negative or -positive chronic active hepatitis or chronic persistent hepatitis to define the relationship between immunoregulatory activity and the HLA-B8 and B12 phenotypes. Suppressor T-cell activity measured by a concanavalin A-induced suppressor system using allogeneic responder cells was dependent on which individual was selected as a source of responder cells. No differences were noted using isogeneic cells as responders. Suppressor T-cell activity measured by the effect of a noninduced suppressor cell on a mixed leukocyte culture was not different from controls. Increased prostaglandin-producing suppressor cell activity was found in patients with hepatitis B-negative (p < 0.005) and hepatitis B-positive (p < 0.05) chronic active hepatitis. When results of the suppressor activities were compared among patients with chronic hepatitis dependent on the presence of HLA-B8, B12, or neither of these phenotypes, no significant differences were present. These results provide further evidence of altered immunoregulatory function in patients with chronic active hepatitis, which may reflect increased suppression by a population of prostaglandin-producing suppressor cells. The results do not, however, suggest that a gene coding for altered immune regulation is linked to HLA-B8 or B12.
The depth of the honeybee's backup sun-compass systems

Honeybees have at least three compass mechanisms: a magnetic compass; a celestial or sun compass, based on the daily rotation of the sun and sun-linked skylight patterns; and a backup celestial compass based on a memory of the sun's movements over time in relation to the landscape. The interactions of these compass systems have yet to be fully elucidated, but the celestial compass is primary in most contexts, the magnetic compass is a backup in certain contexts, and the bees' memory of the sun's course in relation to the landscape is a backup system for cloudy days. Here we ask whether bees have any further compass systems, for example a memory of the sun's movements over time in relation to the magnetic field. To test this, we challenged bees to locate the sun when their known celestial compass systems were unavailable, that is, under overcast skies in unfamiliar landscapes. We measured the bees' knowledge of the sun's location by observing their waggle dances, by which foragers indicate the directions toward food sources in relation to the sun's compass bearing. We found that bees have no celestial compass systems beyond those already known: under overcast skies in unfamiliar landscapes, bees attempt to use their landscape-based backup system to locate the sun, matching the landscapes or skylines at the test sites with those at their natal sites as best they can, even if the matches are poor and yield weak or inconsistent orientation.
Block and Traditional Schedules: Effects on Students with and without Disabilities in High School.

The purpose of this study was to compare the effects of traditional and block schedules on the academic achievement of high school students with and without disabilities. Achievement data were collected from the cumulative records and Individual Education Plans of 160 students with disabilities and the cumulative records of 460 students without disabilities. Achievement was measured by students' GPA; state-mandated tests in reading language, math, science, and social studies; and college entrance ACT Results showed no difference on all comparisons between students with disabilities attending block-scheduled high schools and students with disabilities attending traditional-scheduled high schools. Similar results were found for students without disabilities. Teachers on both schedules reported high levels of satisfaction and comparable amounts of time on instructional activities.