cssi/SciSciGPT-SciSciNet huggingface dataset:
Experimental implementation of multichannel surface wave analysis of a concrete pipe along lengthwise direction

Abstract This is a follow up to our previous paper (Jaganathan, 2019) where the multichannel surface wave (MASW) analysis of a concrete pipe segment was proposed. In that paper, this method was experimentally demonstrated using elastic waves that propagate along the circumferential direction of a reinforced concrete pipe. This paper presents the experimental implementation using waves that propagate along the axial direction of the pipe and its elastic properties along a particular lengthwise cross-section are determined. A numerical validation is conducted by feeding the extracted material properties into a finite element based elastodynamic model. The P-wave velocity estimated by the multichannel approach is used in conjunction with the impact echo analysis to verify wall thickness. In the second half of the paper, multichannel analysis of buried pipes are discussed. Specifically, the effect of soil cover on the dispersion images obtained from the pipe wall is evaluated. Synthetic records are used for this purpose. Dispersion images of a buried pipe for several soil types are generated and compared.
Prototype energy models for data centers

Abstract Data centers in the United States consume about two percent of the nation’s electricity. Because heat gains from IT equipment drive cooling demand, data centers offer unique opportunities for energy savings. However, no prototype energy model for data centers is available in the suite of existing U.S. Department of Energy’s Commercial Prototype Building Models. This study presented the development of two new data center prototype models and their implementation in OpenStudio and EnergyPlus. The small-size data center model represents a computer room in a building served by computer room air conditioners (CRACs); while the large-sized model represents stand-alone data centers served by computer room air handlers (CRAHs) with a central chiller plant. For each data center model, two levels of IT equipment (ITE) load density were considered, to cover the wide range of IT power density of data centers: 40 and 100 W/ft2 (430 and 1076 W/m2) for the computer room, and 100 and 500 W/ft2 (1076 and 5382 W/m2) for the stand-alone data center. All other assumptions, such as building envelope, lighting, HVAC efficiencies and schedules, were based on the minimal requirements of ASHRAE Standard 90.1 at various vintages. We introduced a novel concept of supply and return air approach temperatures to capture the essential effects of non-uniform airflow and temperature distribution in data centers. The approach temperatures were pre-computed by computational fluid dynamics (CFD) simulations for various configurations of ITE loads and airflow containment management in data centers. A new feature was developed in EnergyPlus to implement the approach temperature method. A case study was conducted to demonstrate the use of the data center models. The two data center models cover all U.S. climate zones and can be used to evaluate energy saving measures for data centers, as well as to support development of data center energy efficiency codes and standards.
Bounded Religious Automation at Work: Communicating Human Authority in Artificial Intelligence Networks:

Existential threats to human work and leadership have been expressed over intensifying human-machine communication, and the development of robots and artificial intelligence (AI). Yet popular texts...
Regulatory Analysis the Modern Concept of Law: A Response

Regulatory analysis, which includes cost-benefit calculations, is based on a modern conception of law. It can only be understood—and certainly can only be improved—if that conception is fully recognized. In the pre-modern era, law was conceived as a set of normatively-based limits on human behavior designed to maintain public order. In the administrative state, law is treated as a means of implementing consciously-chosen policies designed to achieve public welfare. Regulatory analysis is based on this administrative conception of law. It does not address questions about whether an enactment is a correct interpretation of principle, but rather whether the enactment is likely to achieve some intended public welfare improvement. Professor Cary Coglianese has proposed that two elements of regulatory analysis, namely cost-benefit analysis and evaluation of regulatory consequences, be imposed by statute on independent agencies. This is an excellent suggestion, but the modern concept of law on which it is based suggests that we should go further, for both independent and executive agencies. We should not only require agencies to conduct cost benefit analysis, a component of policy analysis, but also require that they follow, and document, the whole policy analysis approach. We should not only require them to evaluate their regulations, but we should also incorporate funding for evaluation into virtually all budgetary allocations and fund the agency to experiment with different versions of a regulation as part of that evaluative process.
Characterizing Shoulder Implants in X-Ray Images

This paper studies methods for characterizing shoulder implants in X-ray images of the shoulder, upper arm, and chest region. The task of characterizing in this context entails sub-tasks such as detecting the presence of an implant, segmenting it from the rest of the image, determining its orientation relative to the image and other features such as bones, detecting shape features of the implant, and determining properties of the implant (e.g., manufacturer, model). The task is complicated due to the proximity and similarity of bones and other objects as well as due to potentially low image contrast, spurious edges, and other artifacts. This paper describes the challenges and outlines and evaluates solutions using a recently published dataset of 597 X-ray images of shoulder implants.
Frozen-Permanent Section Discrepancy Rate in Oral Cavity and Oropharyngeal Squamous Cell Carcinoma.

Frozen section evaluation of head and neck squamous cell carcinoma (SCC) is critical for margin status and subsequent patient therapy. In this study, we retrospectively reviewed the rate of frozen-permanent section discrepancies in blocks with two frozen section levels compared to ≥ three levels in oral cavity and oropharyngeal SCCs. A search of the cases with both intraoperative frozen sections and corresponding permanent sections for SCCs in the oral cavity and oropharynx was performed. Frozen sections and permanent slides were compared. The nature of discrepancies was assigned to one of the following: change in diagnosis, margin status, or distance of the tumor from the margin. The cause of the discrepancy was designated as one of the following: block sampling, gross sampling, interpretation, or technical error. The pathologist experience, frozen section technical experience, and intraoperative impact of each discrepancy were also evaluated. A total of 654 frozen and corresponding permanent blocks were assessed. For 532 of the frozen section blocks, two levels were cut, while 122 frozen section blocks had ≥ three levels. Thirty-five frozen-permanent section discrepancies were observed (5.4% of all blocks). Among these, 2.5% had a possible or definitive intraoperative impact. The percentage of discrepancies in the ≥ three levels group (5.7%) was slightly higher than the two-level group (5.3%), and this difference was not statistically significant. For the two-level group, the overall block sampling error rate was 4.5%. This was not significantly different from the 4.1% block sampling error rate seen in the ≥ three levels group. The rate of block sampling discrepancy did not show significant differences based on attending or frozen section technical experience. A change in margin distance (closer margin detected on permanent) occurred in 4% of the blocks and involved 16% of the patients. This review of oral cavity and oropharynx SCCs frozen/permanent section discrepancies shows that the error rate is not significantly different depending on the number of levels cut. The results suggest that always performing more than two frozen section levels may not yield a decreased discrepancy rate. A change in margin distance occurred quite frequently, but only in rare cases it had a definitive impact on the intraoperative management. Given the importance of correct intraoperative diagnosis in patient management, additional levels may be warranted depending on the clinical scenario.
“More & Earlier”: Neoliberalism and Primary English Education in Mexican Public Schools

As global English expands, developing countries feel the pressure that, in order to remain globally competitive, they must increase the number of people with English proficiency. In response, many countries have significantly expanded English instruction in public schools by implementing primary English language teaching (PELT) programs. This is particularly true in countries in Southeast Asia and Latin America, where national Ministries of Education have taken a “more & earlier” approach, integrating English into the public primary curriculum. Children start learning English younger and study the language more during their basic education. The author argues that this language education policy shift toward expanding English in the public education curricula in developing countries is best understood as a shift from past models of elite English bilingualism to policies intended to support the macroacquisition, or general proficiency in English. The rationale for this policy change is framed in terms of the “modernization” and “internationalization” of a country’s public education system, and hence should be understood as part of the response to align education curricula and programs with neoliberal policies. The author examines Mexico’s recent national English program for public primary schools as a case study in the implementation of neoliberal language policy.
Application of Soil Mechanics in Designing Building Foundations

The first part of this paper reviews the causes of building settlements, and summarizes what soil mechanics has to offer as a basis for the design of building foundations. In the second part are de...
Sulfate and sulfide sulfur isotopes (δ34S and δ33S) measured by solution and laser ablation MC-ICP-MS: An enhanced approach using external correction

Abstract Isotope ratio measurements using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS) commonly use standard-sample bracketing with a single isotope standard for mass bias correction for elements with narrow-range isotope systems measured by MC-ICP-MS, e.g. Cu, Fe, Zn, and Hg. However, sulfur (S) isotopic composition (δ 34 S) in nature can range from at least − 40 to + 40‰, potentially exceeding the ability of standard-sample bracketing using a single sulfur isotope standard to accurately correct for mass bias. Isotopic fractionation via solution and laser ablation introduction was determined during sulfate sulfur (S sulfate ) isotope measurements. An external isotope calibration curve was constructed using in-house and National Institute of Standards and Technology (NIST) S sulfate isotope reference materials (RM) in an attempt to correct for the difference. The ability of external isotope correction for S sulfate isotope measurements was evaluated by analyzing NIST and United States Geological Survey (USGS) S sulfate isotope reference materials as unknowns. Differences in δ 34 S sulfate between standard-sample bracketing and standard-sample bracketing with external isotope correction for sulfate samples ranged from 0.72‰ to 2.35‰ over a δ 34 S range of 1.40‰ to 21.17‰. No isotopic differences were observed when analyzing S sulfide reference materials over a δ 34 S sulfide range of − 32.1‰ to 17.3‰ and a δ 33 S range of − 16.5‰ to 8.9‰ via laser ablation (LA)-MC-ICP-MS. Here, we identify a possible plasma induced fractionation for S sulfate and describe a new method using external isotope calibration corrections using solution and LA-MC-ICP-MS.
Establishing Intracellular Infection: Modulation of Host Cell Functions (Anaplasmataceae)

Studies of representative members, primarily Anaplasma phagocytophilum and Ehrlichia chaffeensis, have shed much light on the exquisite mechanisms by which Anaplasmataceae pathogens manipulate their host cells, and are discussed following overviews of the diseases that they cause, their notable genomic features, and their infection and developmental cycles. The secretion of type IV secretion system (T4SS) effectors into host cells is critical for survival of facultative and obligate intracellular bacterial pathogens. Apoptosis is initiated by enzymatic caspases, which are inactive until they are activated by apoptotic signaling pathways. The A. phagocytophilum-occupied vacuole (ApV) excludes fusion with secretory vesicles and specific granules harboring NADPH oxidase and proteolytic enzymes. Preferentially recruiting Rab GTPases that are predominantly found on slow recycling endosomes potentially provides A. phagocytophilum with four intracellular survival advantages. First, A. phagocytophilum is auxotrophic for 16 amino acids. Second, the mechanism by which A. phagocytophilum obtains LDL endocytic pathway-derived cholesterol for incorporation into its cell wall is unknown. Third, continual delivery of recycling endosomes to the ApV would conceivably provide an unlimited supply of host membrane material to allow for expansion of the AVM, which would be necessary to accommodate growing intravacuolar bacterial populations. Fourth, by coating the AVM with recycling endosome- associated Rab GTPases, the ApV camouflages itself as a recycling endosome, which is likely a means by which it protects itself from fusing with lysosomes. Finally, much of what authors know regarding Anaplasmataceae pathogen manipulation of host cell functions is derived from studies of A. phagocytophilum and E. chaffeensis.
Fitting Models to Composite Materials Fatigue Data

A new procedure for fitting fatigue models (consisting of a deterministic equation defining the shape of the S-N curve and a probabilistic description of the data scatter) is presented. The procedure consists of (1) transforming the fatigue data into equivalent static strength data by using the deterministic equation in the fatigue model with unknown parameters, (2) obtaining the maximum-likelihood estimates for the parameters of the (two-parameter Weibull) distribution describing the equivalent static strength data, and (3) repeating Steps 1 and 2 until the largest maximum-likelihood estimate of the shape parameter is obtained. The procedure can handle runouts and tab failures through progressive censoring. Finally, the procedure is well defined when small fatigue data samples are available.
Exiting or retaining owner-occupied housing in the United States 1999–2009: How do social programs matter? ☆

Abstract This research examines exits from homeownership in the United States between 1999 and 2009 using data from the Panel Study of Income Dynamics. We first document the extent to which homeowners exited owned housing (to a rental unit or a rent-free unit) during that time period. Second, we examine how socio-demographic characteristics, housing characteristics, debt levels, and receipt of public and private transfers are associated with exiting (or retaining) homeownership, with a particular focus on whether transfers counteract earnings decreases and/or housing cost increases to assist homeowners in retaining their homes. We also investigate whether these associations differ for several subgroups of homeowners defined by their location in the income distribution and race. Findings from regression models that include individual, year, and state fixed effects highlight the role of both labor markets and housing markets in influencing exits from homeownership. More generous and universal public transfers (such as OASDI) appear to help owners retain homes, whereas less generous and means-tested transfers do not. At the same time, the influences of universal transfers on retaining a home are small in magnitude compared to those of decreases in earnings and home values as well as increases in payment-to-income and consumer debt-to-income ratios.
On Selecting an Algorithm for Fuzzy Optimization

Formulations for fuzzy and possibilistic optimization abound in the literature, but few are implemented in practice. This paper investigates the theory, semantics, and efficacy of a selection of significant fuzzy and possibilistic optimization algorithms via their application to a well-known large-scale problem: the radiation therapy planning problem. The algorithms are compared, critiqued, and organized with the following objective in mind: to guide a decision maker in the selection and implementation of a fuzzy or possibilistic optimization algorithm.
Progenitor Cells of the Mammalian Forebrain: Their Types and Distribution

ABSTRACT Important events underlying the proper functioning of the central nervous system include the production, assembly, and differentiation of appropriate types and numbers of cells. The mechanisms that control these phenomena have been difficult to unravel in the mammalian forebrain because of its diverse cellular composition and because of the displacement of its cells from their site of origin to their permanent location during development. Nonetheless, headway has been made in our understanding of how cells of the developing forebrain “decide” where to go and what to become. The availability in the past few years of replication-defective recombinant retroviruses that encode heritable and easily detectable marker genes, as well as a class of fluorescent lipophilic markers (i.e., molecules that associate with lipids in membranes), has made it possible to tag progenitor cells and subsequently identify their progeny either morphologically or immunohistochemically. This approach has been used to determine the properties and location of the progenitor cells of the forebrain and to analyze the distribution and phenotype of lineally related cells in the developing and mature forebrain. The findings obtained by these studies support the notion that the progeny of individual telencephalic germinal-zone cells generally remain in relatively close proximity because they traverse similar paths. Furthermore, progenitor cells of the prenatal and postnatal brain are a composite of specialized cell types, and the progeny of individual progenitors share a common phenotype. This chapter focuses on the similarities and differences between how the cerebral cortex and the olfactory bulb develop, as a way of deducing the range of mechanisms responsible for generating the diversity of cell types characteristic of each structure.
Displacements of Matrix Products

For fixed matrices M and N, either of the linear transformations A ↦ A-MAN or or A ↦ MA-AN is called a displacement of the matrix A. Displacement can greatly reduce the rank of structured matrices, such as circulant, Vandermonde, Toeplitz and Hankel matrices. This rank reduction has been widely used for inverting structured matrices. In this paper, several formulas are given for both types of displacements applied to matrix products. Very few results for matrix products are known, yet they are desirable for dealing with matrix equations such as P2=P, AA*=I, and A=U∑V*.
Multicriteria parameter estimation for models of stream chemical composition

[1] The inability to develop an accurate and precise parameter estimation method for catchment hydrochemical models has been a persistent problem. We investigate the use of multicriteria calibration techniques and the selection of the criteria as a first step in solving this problem. We applied a multicriteria search algorithm to the Alpine Hydrochemical Model (AHM) of the Emerald Lake watershed, Sequoia National Park, California. A total of 21 chemical and hydrologic criteria were available for determining model performance. Four subsets of these criteria were selected for the multicriteria analysis using three different methods. The first set used the four least correlated observations of stream chemical composition. A second set of criteria was determined by using the four species with the least correlated root mean square error criteria values (ρ < 0.05 for each pair). Finally, two sets were chosen using the results of a multicriteria sensitivity analysis. The most accurate and precise results were observed using criteria selected using results from a sensitivity analysis, with the correlation analyses being a poor method for selecting criteria. This set of criteria emphasizes attributes of the model structure, the observations, and our understanding of the processes influencing watershed hydrology and water quality. Also, our results gave improved estimates of several hydrologic and biogeochemical processes in addition to identifying a flaw in the current representation of mineral weathering within the AHM, as applied to the Emerald Lake watershed.
Thermal degradation of glycerol/adipic acid hyperbranched poly(ester)s containing either hydroxyl or carboxyl end-groups

Glycerol-derived hyperbranched poly(ester)s offer superior properties for utilization in agriculture, personal care and biomedical areas. These materials are compatible with bio-environments, are generally nontoxic and are biodegradable. When either hydroxyl or carboxyl end-groups are present, they may be conjugated with a wide variety of active agents to provide controlled-release compositions. Glycerol/adipic acid hyperbranched poly(ester)s have been prepared and characterized using chromatographic, spectroscopic and thermal analysis methods. The thermal degradation characteristics of these polymers have been established using thermogravimetry and infrared spectroscopy. The prominent feature for the degradation for polymers with hydroxyl end-groups is cross-linking ether formation while that for polymers with carboxyl end-groups is decarboxylation.
Optimal Feedback Control of Power Systems Using Eigenstructure Assignment and Particle Swarm Optimization

The US Navy has a continuing interest and investment in basic and applied research in the area of automation and control. The potential naval applications for this research are numerous and wide ranging. The need for advances in control and automation systems exists from missile defense, to shipboard auxiliary systems, to naval aircraft, and virtually everywhere in between. This research is performed in industry, academia, and in naval laboratories across the nation. This paper will detail particular research in control theory being performed in the area of automation and controls in the naval laboratories. A particle swarm optimization algorithm is used to manipulate the state and control weighting matrices of a linear quadratic regulator to achieve an optimal control for a desired eigenstructure. The algorithm is demonstrated on a nonlinear power system model, and is found to be highly effective in the stabilization of the system output performance, showing both rapid convergence and a closed loop eigenstructure very close to the specified eigenstructure.
Design and optimization of ESD lateral NPN device in 14nm FinFET SOI CMOS technology

We present the development of ESD lateral NPN device in 14nm FinFET SOI CMOS technology using body-contact and floating-body approaches. The effects of key design factors including base length, base doping, body resistance on the triggering and ESD performance of LNPN device are investigated to achieve an optimized design.
Effect of drug loading on laser modification of polymer biodegradation

Abstract Biodegradable polymer is promising in drug delivery applications, while its degradation characteristics include an undesirably slow induction period of drug release. Through modifying polymer surface crystallinity, laser melting accelerates initial polymer degradation and potentially shortens the induction period of drug release. Effect of drug loading on laser modification of polymer degradation is investigated in this study. With a higher drug concentration, effect of laser melting on crystallinity and degradation modification is reduced. This is attributed to the fact that laser energy is partly absorbed by drug molecules, and less energy is available to melt the polymer matrix.
The 1988 National Maternal and Infant Health Survey: Design, Content, and Data Availability

The 1988 National Maternal and Infant Health Survey was conducted by the National Center for Health Statistics to study factors related to poor pregnancy outcome, such as adequacy of prenatal care; inadequate and excessive weight gain during pregnancy; maternal smoking, drinking, and drug use; and pregnancy and delivery complications. The survey is a nationally representative sample of 11,000 women who had live births, 4000 who had late fetal deaths, and 6000 who had infant deaths in 1988. Mothers were mailed questionnaires based on information from certificates of live birth, reports of fetal death, and certificates of infant death. Information supplied by the mother, prenatal care providers, and hospitals of delivery was linked with the vital records to expand knowledge of maternal and infant health in the United States. Data collection from the Longitudinal Followup of mothers in the survey began in January 1991. It provides information on health and development of low- and very low-birthweight babies, child care and safety, maternal health, maternal depression, and plans for adoption and foster care. Both surveys will provide useful data for clinicians in maternal and child health.
Evaluation of microbial survival post-incidence on fresh Mozzarella cheese1

Commercial fresh Mozzarella cheese is made by direct acidification and is stored dry or in water without salt addition. The cheese has a shelf life of 6 wk, but usually develops an off-flavor and loses textural integrity by 4 wk, potentially due to the lack of salt and high moisture that allow the outgrowth of undesirable bacteria. To understand how microbial incidence affects cheese quality and how incident pathogen-related bacteria are limited by salt level during refrigerated storage, we made fresh Mozzarella cheese with high (2%) and low (0.5%) salt. The high-salt cheese was packaged and stored dry. The low-salt cheese was packaged and stored either dry or in 0.5% salt brine. One portion of cheeses was evaluated for surviving incident microbes by aerobic plate counts, coliform counts, and psychrophilic bacterial counts, of which coliforms and psychrophiles were not detected over 9 wk. Aerobic plate counts remained at 100 to 300 cfu/g up to 2 wk but increased by 1,000- to 10,000-fold between 4 and 6 wk at all salt levels and storage conditions. Other portions of cheeses were inoculated with either Escherichia coli or Enterococcus faecalis, both of which increased by 100-fold over 90 d of storage. Interestingly, E. coli added to the cheese brine first grew in the brine by 100-fold before attaching to the cheese, whereas Ent. faecalis attached to the cheese within 24h and grew only on the cheese. We conclude that incident bacteria, even from similar environments, may attach to cheese curd and survive differently in fresh Mozzarella cheese than in brine. Overall, 2% salt was insufficient to control bacterial growth, and slow-growing, cold- and salt-tolerant bacteria may survive and spoil fresh Mozzarella cheese.
The role of imaging in renal and extra‐renal rhabdoid tumours

SUMMARY Rhabdoid tumour of the kidney is an uncommon malignancy with a poor prognosis that usually occurs in childhood. Certain imaging features may help distinguish this lesion from the much more common Wilmstumour ‘. Extra-renal rhabdoid tumours appear to have no specific imaging characteristics.
Tourism development and resistance in China

Abstract In 2013, the Dong villagers of Zhaoxing in Guizhou province expelled a Han-managed tourism company from their community and from their tourist enterprises. Far from being passive and homogeneous, ethnographic data reveal ethnic populations negotiate tourism development in a variety of ways. Using concepts of livelihood, resistance, agency and ethnicity, this article reveals: villagers responded to tourism development differently according to their livelihood strategies; villagers sided with local authorities of their own ethnic group in order to resist Han-led higher levels of government and villagers responded to non-local stakeholders’ infringement rather than to the presence of tourists. These findings point to the necessity of detailed ethnographic case studies to understand the context within which tourism development occurs in China.
Control of the Integral Membrane Proton Pump, Bacteriorhodopsin, by Purple Membrane Lipids of Halobacterium halobium

Brief exposure of purple membrane (PM) to dilute Triton X-100 eliminates the actinic light effect on the relative amounts of fast M (Mf) and slow M (Ms) intermediates and alters the character and kinetics of the photocycle, without destroying the native BR trimers (Mukhopadhyay et al., 1994). Particular membrane lipids are removed during the Triton treatment, and adding back an extract of membrane lipids can repair most of the affected photocycle behavior (Dracheva et al., 1996). This paper defines conditions which are important in the reconstitution procedure, using a group of quantitative parameters which measure the extents of damage and repair. Circular dichroism in both the UV and visible ranges shows that Triton can disturb both the secondary structure of BR and its ability to polymerize into trimers. Whereas the damage to protein conformation could be reversed by lipids alone, the formation of trimers and recovery of normal photocycle behavior required both lipids and a high salt concentration.
The illusive search for the lowest free energy state of globular proteins and RNAs.

Abstract As a consequence of the one-dimensional storage and transfer of genetic information, DNA → RNA → protein, the process by which globular proteins and RNAs achieve their three-dimensional structure involves folding of a linear chain. The folding process itself could create massive activation barriers that prevent the attainment of many stable protein and RNA structures. We consider several kinds of energy barriers inherent in folding that might serve as kinetic constraints to achieving the lowest energy state. Alternative approaches to forming 3D structure, where a substantial number of weak interactions would be created prior to the formation of all the peptide (or phosphodiester) bonds, might not be subjected to such high barriers. This could lead to unique 3D conformational states, potentially more stable than “native” proteins and RNAs, with new functionalities.
A comment on the evaluation of Fermi integrals

Abstract A way of applying an integral representation of the Fermi function is illustrated.
Numerical simulation of the Gulf Stream and Mid-Ocean eddies

Oceanographic field measurements have revealed intense, transient mesoscale motions in many parts of the world ocean. The circulation of the western North Atlantic, considered in the present study as a rectangular basin, is simulated with a primitive equation model that has five levels and a horizontal grid size of 37 km. The model ocean is driven by a 2.5 gyre pattern of steady zonal wind stress and by a Newtonian-type surface heating. Two cases are considered: the first uses a Laplacian formulation for the subgrid-scale lateral diffusions of heat and momentum; the second uses a highly scale-selective biharmonic formulation for these diffusions. An analysis of the heat transport, in the biharmonic experiment, shows that the horizontal transport of heat by eddies is much larger than the subgrid-scale horizontal heat diffusion. In the Gulf Stream region, the eddy heat transport is comparable to the effect of a lateral diffusion coefficient of 10 to the 7th sq cm/s.
Scombroid Fishes Provide Novel Insights into the Trait/Rate Associations of Molecular Evolution

The study of which life history traits primarily affect molecular evolutionary rates is often confounded by the covariance of these traits. Scombroid fishes (billfishes, tunas, barracudas, and their relatives) are unusual in that their mass-specific metabolic rate is positively associated with body size. This study exploits this atypical pattern of trait variation, which allows for direct tests of whether mass-specific metabolic rate or body size is the more important factor of molecular evolutionary rates. We inferred a phylogeny for scombroids from a supermatrix of molecular and morphological characters and used new phylogenetic comparative approaches to assess the associations of body size and mass-specific metabolic rate with substitution rate. As predicted by the body size hypothesis, there is a negative correlation between body size and substitution rate. However, unexpectedly, we also find a negative association between mass-specific metabolic and substitution rates. These relationships are supported by analyses of the total molecular data, separate mitochondrial and nuclear genes, and individual loci, and they are robust to phylogenetic uncertainty. The molecular evolutionary rates of scombroids are primarily tied to body size. This study demonstrates that groups with novel patterns of trait variation can be particularly informative for identifying which life history traits are the primary factors of molecular evolutionary rates.
ORGANIZATION OF THE DEOXYRIBONUCLEIC ACID REPLICATING SYSTEM IN MAMMALIAN CELLS AS REVEALED BY THE USE OF X-RADIATION AND BROMURACIL DEOXYRIBOSIDE.

Dose-dependent depression of deoxyribonucleic acid study by x-ray irradiation and bromuracil deoxyriboside in mammalian cells
Immunostimulatory activity of LT-IIa, a type II heat-labile enterotoxin of Escherichia coli.

Abstract Certain bacterial molecules potentiate immune responses to parenterally administered antigens. One such molecule that has been intensely investigated is cholera toxin, a type I heat-labile enterotoxin produced by the Gram-negative bacterium Vibrio cholerae . Immunization with a mixture of a foreign antigen and cholera toxin enhances the immune response to the antigen. Similar adjuvant activity is associated with LT-I, a closely related type I heat-labile enterotoxin produced by Escherichia coli . The adjuvant activities of LT-IIa, a member of the type II heat-labile enterotoxins produced by E. coli , have not been described. LT-IIa and CT differ significantly in amino acid sequence of the B polypeptides and in receptor binding affinity. In this study, rats were subcutaneously immunized with fimbrillin, a protein isolated from the bacterium Porphyromonas gingivalis , and with fimbrillin in combination with LT-IIa, the prototypical type II enterotoxin. Previous studies documented that fimbrillin administered alone is a poor immunogen. Animals immunized with the mixture of fimbrillin and LT-IIa produced high titers of specific IgG antibody directed against fimbrillin. Anti-fimbrillin antibody titers in sera from animals receiving the combination of LT-IIa+fimbrillin were comparable to those obtained from sera of animals immunized with cholera toxin+fimbrillin. The results of these experiments demonstrate that LT-IIa exhibits an adjuvant activity that is equal to that of cholera toxin. Recombinant methods have been established for producing large amounts of LT-IIa, an advantage that will likely provide an economic impetus to consider incorporating the enterotoxin as an immunostimulatory agent in future vaccines.
On the diamagnetic susceptibility of a superconductor above the transition temperature

Abstract A model calculation is presented for the magnetization of a superconductor above its transition temperature, T(H c2 ). The contribution of high energy fluctuations is treated in a fashion which is consistent with the microscopic theory and which differs from the treatment using the simple Ginzburg-Landau functional. The result is a generalization of the susceptibility to the case of finite applied field and allows the determination of a characteristic cutoff energy from experiment.
Adrenal insufficiency as the first clinical manifestation of the primary antiphospholipid antibody syndrome

We describe a 60-year-old man who developed clinical symptoms and signs of Addison's disease, which was subsequently confirmed biochemically; no cause was apparent. Several months later the patient represented with a fit, followed by a large and extensive venous thrombosis in the right iliac vein and in the veins of the right leg. He had strongly positive antibodies to cardiolipin, strongly suggesting a diagnosis of primary antiphospholipid syndrome. While Addison's disease is a well-recognized, albeit rare, manifestation of the antiphospholipid syndrome, the Addison's disease preceded other clinical evidence of the syndrome by several months, in our patient, at variance with previous cases described in the literature. The antiphospholipid syndrome should be considered as a possible pathogenetic process in patients presenting with Addison's disease where the aetiology is not obvious.
Model-based scatter correction for fully 3D PET

A method is presented that directly calculates the mean number of scattered coincidences in data acquired with fully 3D positron emission tomography (PET). This method uses a transmission scan, an emission scan, the physics of Compton scatter, and a mathematical model of the scanner in a forward calculation of the number of events for which one photon has undergone a single Compton interaction. The distribution of events for which multiple Compton interactions have occurred is modelled as a linear transformation of the single-scatter distribution. Computational efficiency is achieved by sampling at rates no higher than those required by the scatter distribution and by implementing the algorithm using look-up tables. Evaluation studies in phantoms with large scatter fractions show that the method yields images with quantitative accuracy equivalent to that of slice-collimated PET in clinically useful times.
Do Tyrosine Phenolic Groups Contribute to the Alkaline Transition in the Redox Potential of Cytochrome F

Cytochrome f, a c-type cytochrome involved in the photosynthetic electron transport chain, has a significantly higher redox potential than most other c-type cytochromes, ranging +370 to +380 mV. Like cytochrome c, cytochrome f also exhibits an alkaline transition in which the redox potential becomes pH dependent at high pH. In the case of cytochrome c, this has been attributed to replacement of the methionine sulfur serving as the sixth iron ligand by a deprotonated amino group. This cannot be the cause for the alkaline transition in cytochrome f as there is no methionine ligand to the iron, the sixth position being occupied by the N-terminal amino group. Three tyrosine phenolic groups (Y1, Y9, and Y160) are found in close proximity to the heme in the cytochrome f structure. To explore the possibility that the ionization of one or more of these tyrosines might be responsible for the alkaline transition, we have performed site directed mutagenesis, replacing each with a phenylalanine residue which lacks an ionizible group. Each of these mutants was found to have a redox potential of 375-380 mV at pH 7.0 which became pH dependent above pH 9.0 (apparent pKa 9.3). It thus seems unlikely that any of these tyrosine residues contributes to the alkaline transition of the redox potentials in cytochrome f. Redox properties of Y160L and R156L mutants will also be described.
How does culture shape students’ perceptions of scientists? Cross-national comparative study of American and Chinese elementary students

For decades, researchers have been convinced that one stereotypic image of scientists existed among children worldwide (Chambers, 1983; Chiang & Guo, 1996; Fung, 2002; Maoldomhnaigh & Hunt, 1988; Newton & Newton, 1992, 1998; She, 1998; Song, Pak, & Jang, 1992). This study, however, moves beyond that stereotypic image and examines students’ perceptions of scientists. The purpose of this study is to illustrate that students are influenced not only by the personal images they hold of scientists, but also by cultural impressions and the style of the science courses they experience in school. By combining a contemporary perspective and a creative method of analyzing student perceptions, a theoretical understanding of how students interpret scientists and their work was developed. Elementary school children (N=1,350) in the United States and China were enrolled in this study, and drawing exercises were utilized to provide new evidence and a fresh perspective regarding the way students perceive scientists. Based on the findings of this research, more American students included the traditional image of a science laboratory with chemicals in their pictorial depictions of scientists, while Chinese students included robots in their drawings. While students in both countries demonstrated misconceptions about scientists, this study identifies those misconceptions as significantly different, yet inherently related, to students’ individual cultures, contrary to previous studies. This study also demonstrates that a child’s environment can be influenced by their existing culture, and thus learning, or perceiving the role of scientists, can be directly influenced since each classroom is a culture of its own. Finally, this study demonstrates that a child’s sense of who can be a scientist, where scientists work, and what scientists do is influenced by cultural experiences. Today, with fewer students pursuing science careers, these findings are especially noteworthy.
Ethynylated aromatics as high temperature matrix resins

Difunctional and trifunctional arylacetylenes were used as monomers to form thermoset matrix resin composites. Composites can be hot pressed at 180 C to react 80 percent of the acetylene groups. Crosslinking is completed by postcuring at 350 C. The postcured resins are thermally stable to nominally 460 C in air. As a result of their high crosslink density, the matrix exhibits brittle failure when unaxial composites are tested in tension. Failure of both uniaxial tensile and flexural specimens occurs in shear at the fiber matrix interface. Tensile fracture stresses for 0 deg composites fabricated with 60 v/o Celion 6K graphite fiber were 827 MPa. The strain to failure was 0.5 percent. Composites fabricated with 8 harness satin Celion cloth (Fiberite 1133) and tested in tension also failed in shear at tensile stresses of 413 MPa.
A survey of the use of 2D ultrasound guidance for insertion of central venous catheters by UK consultant paediatric anaesthetists.

Summary Background and objective: National Institute for Clinical Excellence guidance states that 2D imaging ultrasound guidance should be used when inserting internal jugular venous lines in adults and children in the elective situation and should be considered in most clinical circumstances requiring central venous catheter insertion. This survey explored the availability, training and use of ultrasound devices by consultant paediatric anaesthetists in the UK. Methods: A questionnaire was distributed to UK members of the Association of Paediatric Anaesthetists of Great Britain and Ireland. Results: There was a response rate of 63% and of those responding, 212 (81%) inserted paediatric central venous catheters. Ultrasound devices were available in the workplace of 216 (82%) and the average number of devices available per department was two. For elective paediatric theatre cases, 26% of paediatric anaesthetists with access to an ultrasound device always used it when inserting an internal jugular central venous line. The majority (74%) of respondents had received training in the use of 2D ultrasound. Conclusions: National Institute for Clinical Excellence guidance on the use of ultrasound locating devices for placing central venous catheters is not universally adhered to. Among the reasons for this are problems with availability of equipment, lack of training in the use of ultrasound and non-acceptance of the guidelines.
Development of Novel Cytoplasmic Male Sterile Source from Dongxiang Wild Rice (Oryza rufipogon)

This study was conducted to develop and characterize a novel cytoplasmic male sterile (CMS) source which was identified from Dongxiang wild rice (Oryza rufipogon) by crossing Dongxiang wild rice as female with Zhongzao 35, an indica inbred variety, as male and continuous backcrossing with Zhongzao 35. Observation under optical microscope manifested that this novel CMS belonged to typical abortion type with less pollen compared with wild abortive type cytoplasm (CMS-WA). Sequential planting showed that this novel CMS has complete and stable male sterility. Testcross experiment showed that all the 24 tested materials including maintainer and restorer lines of CMS-WA and Honglian type cytoplasm (CMS-HL) and other indica inbred varieties are the maintainers with complete maintaining ability, suggesting that this novel CMS has fertility restoration totally different from CMS-WA and CMS-HL and belongs to a novel type of CMS. So far, we only discovered a unique fertility restoration source for this novel CMS. Inheritance analysis showed that the fertility restoration of this CMS was governed by three pairs of independent dominant genes. Prospect for application of this novel CMS system in hybrid rice breeding was also discussed.
Organic nitrogen and caloric content of detritus: II. Microbial biomass and activity

The effects of organic nitrogen, total caloric and/or ‘available’ caloric content on the regulation of microbial dynamics were studied using 23 types of detrital rations. Because most natural benthic systems rarely receive rations above 50 mg N m−2 day−1, the results of this work predicts that the organic nitrogen content of the detrital ration is the primary factor regulating microbial metabolism. Estimates of microbial biomass (total adenylates, A) and activity (rates of O2 consumption, CO2 production and nitrogen fixation) were measured at low (>3 to 100 mg N m−2 day−1) and high rations (>100 mg N m−2 day−1 to 216 mg N m−2 day−1). At low rations microbial biomass, activity and the mineralization (CO2) of ‘available’ detrital carbon per unit microbial biomass (CO2: A ratio) correlated best with the nitrogen content of the detritus while respiration per unit microbial biomass (O2:A) correlated best with ‘available’ caloric content. At high rations, microbial biomass and activity correlated best with ‘available’ caloric content. In all cases the metabolic quotient (CO2:O2) correlated best with ‘available’ calories and in no case did total caloric content become an important factor in microbial dynamics. This work suggests the rate of organic enrichment to benthic systems is an important variable to microbial dynamics as is the organic nitrogen and/or ‘available’ caloric content of the ration. It also suggests the importance of relying on more than one type of measurement and in determining the ‘availability’ of the detritus to detritivores in nutritional studies.
Synthesis and characterization of neutral and anionic cellulosic amphiphiles

Abstract Polymer design and selection are crucial to the development of amorphous solid dispersions (ASD) for solubilization of otherwise poorly water-soluble drugs. The matrix polymer is required to interact strongly at the molecular level with the drug to prevent recrystallization, but must also be able to release the drug at an adequate rate upon entering the absorptive portion of the digestive tract. Herein we report versatile syntheses of a non-ionic, water-soluble cellulosic polymer family, cellulose trioxodecanoates, containing a hydrophilic oligo(ethylene oxide) side chain. This series of cellulose derivatives is designed for both adequate stabilization of amorphous drugs with high crystallization tendency, and timely release of those drugs. Alternatively, these polymers can be rendered anionic by also appending a pH-responsive ω-carboxyalkanoate group. Detailed structural information and structure–property relationship characterization of these amphiphilic polymers are described, which will permit evaluation of these materials as ASD polymers for enhancement of drug solubility and bioavailability.