cssi/SciSciGPT-SciSciNet huggingface dataset:
Simultaneous ligand and cation exchange in PbSe/CdSe nanocrystal films

Abstract Trap states formed at the surface of colloidal semiconductor nanocrystals can have deleterious impact on performance in emerging optoelectronic applications. To mitigate surface traps in nanocrystal thin films we investigated simultaneous surface passivation and ligand exchange for PbSe nanocrystal films via treatment with a cadmium acetate solution. We show that a kinetically limited surface cation exchange produces a thin CdxPb1 − xSe shell that effectively passivates the nanocrystal surface as confirmed by increased photoluminescence intensity and photoluminescence lifetime. Ligand exchange to acetate ligands is confirmed via Fourier transform infrared spectroscopy and grazing incidence small angle X-ray scattering. We studied the impact of the cadmium acetate treatment on interparticle coupling and found that the reduced interparticle spacing and limited shell thickness leads to increased Forster resonant energy transfer in nanocrystal films. Simultaneous cation/ligand exchange enables the production of heterostructured nanocrystal films with properties like Quasi-Type II nanocrystals synthesized in solution.
Efficient parallel term matching and anti-unification

In this paper we present optimal processor x time parallel algorithms for term matching and anti-unification of terms represented as trees. Term matching is the special case of unification in which one of the terms is restricted to contain no variables. It has wide applicability to logic programming, term rewriting systems and symbolic pattern matching. Anti-unification is the dual problem of unification in which one computes the most specific generalization of two terms. It has application to inductive inference and theorem proving. Our algorithms run in O(log2N) time using N/log2N processors on a shared-memory model of computation that prohibits simultaneous reads or writes (EREW PRAM). These algorithms are the first polylogarithmic-time EREW algorithms with a processor x time product of the same order as that of their sequential counterparts, thereby permitting optimal speed-ups using any number of processors up to N/log2N. We also use the techniques developed in the paper to provide an N/log N-processor, O(log N)-time algorithm for a shared-memory model that allows both simultaneous reads and simultaneous writes (CRCW PRAM).
The Politics of American Education

This comprehensive overview documents and explains who influences educational policy and how, bringing to life the realities of schooling in the 21st century and revealing the ongoing ideological struggles at play.
Strength and Corrosion Behavior of a SiC Particulate Reinforced Al2O3 Composite in Hot Coal Combustion Environments

As part of an effort to evaluate the use of advanced ceramics in a new generation of coal-fired power plants, a SiC particulate reinforced Al{sub 2}O{sub 3} has been exposed to corrosive coal slag in a laboratory furnace and two pilot scale caombustors. Results show increased corrosive attack with temperature and that only slight changes in temperature may significantly alter the degree of strength degradation due to corrosive attack. The present results are part of a larger experimental matrix evaluating the behavior of ceramics in the coal combustion environment.
The enrichment of lithium isotopes by ion exchange chromatography: The influence of eluent concentration on the separation factor☆

Abstract The influence of eluent concentration on the separation factor for lithium isotopes was examined. With Dowex-50 and Zeo-Karb resins the separation factors decreased with increasing eluent concentration. Comparable results were obtained using either chloride or acetate eluents. The results were consistent with the ion exchange selectivity theory for the elements.
Stable Carbon and Oxygen Isotope Spacing Between Bone and Tooth Collagen and Hydroxyapatite in Human Archaeological Remains

Spacing between stable isotope values in bones and teeth is a valuable tool for examining dietary influences and diagenesis. This study examines carbon and oxygen isotope values from collagen and hydroxyapatite (structural carbonate and phosphate) in archaeological human bones and teeth to derive species-specific correlation equations and isotope spacing values. The δ13Ccollagen and δ13Cstructural carbonate in bone and dentin collagen show a strong correlation (R = 0.87, 0.90, respectively) with an average Δ13Ccarb-coll spacing of 5.4‰. The consistency of this isotope spacing with other large mammals and in humans with both low and high protein intake (as indicated by enriched δ15N values) suggests a similar allocation of protein-derived carbon and whole diet-derived carbon to collagen and structural carbonates, respectively, as other terrestrial mammals regardless of absolute meat intake. The δ18Ostructural carbonate and δ18Ophosphate show the strongest correlation in enamel (R = 0.65), weaker correlations in dentin (R = 0.59) and bone (R = 0.35), with an average Δ18Ocarb-phos of 7.8‰. This isotope spacing is slightly lower than previously reported for large mammals and limited available data for humans. The results potentially indicate species-specific fractionations and differing access to body water and blood-dissolved inorganic carbonates in the presence of collagen formation. The use of correlation between δ18Ostructural carbonate and δ18Ophosphate to determine diagenetic state is not recommended. The strength of this correlation observed in bones and teeth is variable and alternate indicators of diagenetic state (i.e. C:N ratios of collagen) provide more robust and independent evidence of isotope preservation despite presence/absence of a strong isotope correlation. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Phospholipid metabolism during development of the brine shrimp Artemia salina. I. Incorporation of cytidine 5'-phosphate into cytidine diphosphate choline by a microsomal enzyme system.

Abstract An enzyme that converts CMP into CDP-choline has been demonstrated in microsomal preparations of larvae of Artemia salina . We conclude that this enzyme is CDP-choline: 1,2-diglyceride cholinephosphotransferase (EC 2.7.8.2) and that the steady-state of the reaction at low concentrations of CMP appears to favor formation of CDP-choline. The enzymatic activity is completely dependent upon the addition of CMP and metal ions (Mn 2+ , Mg 2+ , or Co 2+ ). No other cytidine compounds can substitute for CMP in the reaction. The optimal pH for formation of CDP-choline is 7.1 and 6.4 with Mg 2+ and Mn 2+ , respectively, as cofactors. Optimal concentrations of Mg 2+ and Mn 2+ are 50 and 5 mM, respectively; and the optimal concentrations of CMP are 75 and 2 μM for Mg 2+ and Mn 2+ , respectively. Enzyme activity is inhibited by Ca 2+ and P -chloromercuribenzoate, whereas F − and iodoacetate have no effect. A stoichiometric relationship exists between the amount of phosphorus lost from phosphatidyl choline and the amount appearing in CDP-choline, indicating that phosphatidyl choline is the source of phosphocholine in CDP-choline formation.
Leukocytes and hypersensitivity reactions: I. Eosinophil response in skin window to ragweed extract, histamine, and compound 4880 in atopic and nonatopic individuals

Abstract Eosinophil counts were made from coverslips obtained from skin windows after intradermal injections of buffered saline, histamine, compound 4880, and mixed ragweed extract in 17 atopic clinically sensitive, 7 skin reacting but clinically nonsensitive, and 11 nonatopic subjects. The concentration of challenging substance was selected on the basis of equal reactivity by titration and wheal size, but other concentrations were also tried. A challenging dose of a size individualized for the subject was necessary to produce the most effective response. When a potent reaginic serum and a proper dose of antigen are used, the eosinophil response in the passively sensitized site is not much different from that in the atopic individual. The response in the atopic, clinically nonsensitive persons appears to be less than the response in those with a history of pollinosis, although the number of subjects and their degree of sensitivity do not permit a final opinion. The eosinophil response to histamine and compound 4880 was found to be greater in atopic clinical than in atopic nonclinical or nonatopic subjects. The eosinophilia from these solutions is usually moderate, is absent at 45 minutes, begins at about 2 hours, is maximal at 6 hours, and is usually negligible at 24 hours. There is considerable variability and inconsistency in the cosinophil determination by this method, some of which is based on factors not yet recognized or corrected. However, it is concluded that conditions which constitute a minimal requirement are: accuracy of dose of challenging substance, a dose selected on basis of titration, repeated trials in the same subject, the counting of at least 1,000 leukocytes, and an averaging of representative areas on the same coverslip.
The Stubborness of Pretexts: An Essay on the Fourth Amendment

On May 29, 2001, the Supreme Court decided Arkansas v. Sullivan, a seemingly unremarkable per-curiam opinion that facilitated the conviction of a small-time meth-dealer whose trial was aborted by pre-trial rulings that were affirmed by his state's highest court. The Supreme Court reversed, ruling that in suppressing Sullivan's drugs, the state courts had ruled flatly contrary to this Court's controlling precedent, Whren v. United States. Five years earlier, Whren had confronted the very question before it in Sullivan: does the Fourth Amendment's injunction against unreasonable searches and seizures prevent the prosecution from using evidence that police discovered by way of a so-called 'pretext'? Whren held that it does not; Sullivan followed suit. The pretext problem had been percolating in the Supreme Court for at least four decades before its putative burial in 1996 by Whren. Indeed, it is one of those areas of criminal procedure where 'confused patchwork,' to lift a term of Justice White's, would be apt. 'Pretext' refers to an action that was done for fishy reasons. In other words, calling something a 'pretext' is not so much a criticism of the action as it is of its motive. And while in just six years Whren already has been cited over 1000 times in court opinions and has been the central subject of some 50 law-review articles, the criteria of pretexts seem to be taken as given; it is their consequences that get all the play. Because I am far from persuaded that we have reached agreement on what those criteria are, I hope to establish them here. In this Essay, therefore, I will reflect on 1) how Whren's failure to acknowledge what counts as a pretext accounts for the residual confusion as to whether or not Whren really has killed off the pretext argument in constitutional criminal procedure; and 2) the extent to which the Court in Sullivan compounded that failure, which I hope I can lightly correct here by distinguishing motives from intentions and then by elaborating the role that each plays, or at least should play, in Fourth Amendment jurisprudence.
The receptor for mouse hepatitis virus in the resistant mouse strain SJL is functional: implications for the requirement of a second factor for viral infection.

Abstract The SJL mouse strain is resistant to infection by some strains of the murine coronavirus mouse hepatitis virus (MHV), such as JHM and A59. The block to virus infection has been variously attributed to defects in virus receptors or virus spread. Since the cellular receptors for MHV, mmCGM1 and mmCGM2, have recently been identified as members of the carcinoembryonic antigen family, we reexamined the possible defectiveness of the MHV receptors in SJL mouse strain. Cloning and sequencing of the cDNAs of both mmCGMs RNAs from SJL mice revealed that they were identical in size to those of the susceptible C57BL/6 (B6) mouse. There was some sequence divergence in the N terminus of the mmCGM molecules between the two mouse strains, resulting in a different number of potential glycosylation sites. This was confirmed by in vitro translation of the mmCGM RNAs, which showed that the glycosylated mmCGM2 of SJL was smaller than that of B6 mice. However, transfection of either mmCGM1 or mmCGM2 from SJL mice into MHV-resistant Cos 7 cells rendered the cells susceptible to MHV infection. The ability of the SJL mmCGM molecules to serve as MHV receptors was comparable to that of those from B6. These molecules are expressed in SJL mouse brain and liver in a similar ratio and in amounts equivalent to those in the B6 mouse. Furthermore, we demonstrated that an SJL-derived cell line was susceptible to A59 but resistant to JHM infection. We concluded that the MHV receptor molecules in the SJL mouse are functional and that the resistance of SJL mice to infection by some MHV strains most likely results from some other factor(s) required for virus entry or some other step(s) in virus replication.
Bacillary characteristics in Whipple's disease: An electron microscopic study

Abstract Extensive electron microscopic observations of 19 intestinal biopsies obtained from 13 patients with untreated Whipple's disease are reported. The outstanding feature is the profuse presence of bacilli free within the lamina propria of the intestinal mucosa and the presence of numerous macrophages containing ingested bacilli. Intestinal epithelial cell invasion by bacilli is identified in 11 patients, and evidence of bacillary invasion is identified within the lymphatic endothelium of 4 patients, within capillary endothelium of 3 patients, within polymorphonuclear leukocytes of 5 patients, and within plasma cells of 2 patients. Reported for the first time is the presence of bacilli within intrinsic smooth muscle of the lamina propria of 2 patients, within intraepithelial lymphocytes of 1 patient, and in mast cells of 1 patient. These observations suggest that the Whipple bacillus is an intracellular pathogen. Intracellular pathogens, unlike pyogenic bacteria, may survive within macrophages. The morphologic appearance of the Whipple bacillus is reviewed. Emphasis is placed upon the unique nature of an outer "membrane" external to the cell wall of Whipple bacilli, a feature that is one of the identifying characteristics of the Whipple bacillus and that may explain the inability to culture the bacillus in vitro.
Generalized state-plane analysis of soft-switching DC-DC converters

Based on generalized switching-cell approach, a generalized state-plane analysis for families of soft-switching DC-to-DC converters is presented. It is shown that the analysis of soft-switching DC-to-DC converter families can be analyzed in terms of a simple two-dimensional state-plane diagram. Complete generalized design equations are also given. It is shown that one generalized transformation table is given for the analyzed families. The basic generalized equations are summarized. The concept of generalized state-plane analysis is applied to selected soft-switching families such as ZVS-QRC, ZCS-QRC, QSW-CC, QSW-CV, ZCT-PWM, and ZVT-PWM. Other switching families can also be analyzed using the state-plane method.
Redefining the differences in gene content between Yersinia pestis and Yersinia pseudotuberculosis using large-scale comparative genomics

Yersinia pestis, the causative agent of plague, is best known for historical pandemics, but still actively causes disease in many parts of the world. Y. pestis is a recently derived clone of the pathogenic species Yersinia pseudotuberculosis, but is more associated with human infection. Numerous studies have documented genomic changes since the two species differentiated, although all of these studies used a relatively small sample set for defining these differences. In this study, we compared the complete genomic content between a diverse set of Y. pestis and Y. pseudotuberculosis genomes, and identified unique loci that could serve as diagnostic markers or for better understanding the evolution and pathogenesis of each group. Comparative genomics analyses also identified subtle variations in gene content between individual monophyletic clades within these species, based on a core genome single nucleotide polymorphism phylogeny that would have been undetected in a less comprehensive genome dataset. We also screened loci that were identified in other published studies as unique to either species and generally found a non-uniform distribution, suggesting that the assignment of these unique genes to either species should be re-evaluated in the context of current sequencing efforts. Overall, this study provides a high-resolution view into the genomic differences between Y. pestis and Y. pseudotuberculosis, demonstrating fine-scale differentiation and unique gene composition in both species.
Experimental pulmonary talcum granuloma and epithelial hyperplasia in the chinchilla.

Chronic pulmonary irritation was induced in the chinchilla with talcum powder. Two effects on the pulmonary parenchyma were (1) exudative pneumonia, progressing quickly to predominantly proliferati...
Classification images of cardiac wall motion abnormalities

Classification images are developed for the diagnosis of the cardiac regional wall motion abnormalities (RWMA). These images suggest a direct diagnosis of RWMA and are void of the information not relevant to the intended diagnostic effort. The computer learns from already diagnosed images the patterns characteristic for diagnostic classes of interest, and then can determine accurately the presence of those patterns in the classification images of a new patient. While the actual development has been tuned to the image data generated by radionuclide equilibrium gated cardiac studies and to the problem of the diagnosis of the left ventricle RWMA, the concept can be readily applied to other imaging problems in radiology. >
Part Consolidation for Additive Manufacturing Demonstrated in the Design of a 3D-Printed Harmonic Drive

The goal of this project is to establish a novel design approach for the additive manufacturing of mechanical transmission systems. Our focus is the design and 3D printing of a harmonic drive. Harmonic drives use the elastic dynamics of metals to create an elliptical rotation, which is what conceives the reduction of speed of the outer piece. Additive manufacturing is used to achieve more complex and precise mechanical structures. Components of less complexity will be 3D printed with polymer and commercial parts will be purchased. There is a need for the creation of new plastics manufacturing processes that define and simplify the decision methods involved in the production. With this project, we will establish the process we consider best for plastic additive manufacturing. The decision of which parts are 3D printed or machined affects the harmonic drive’s cost and lead-time; therefore, several alternatives are systematically analyzed. The final bill of materials contains the list of commercial parts and 3D printed parts. When assembled, a functioning harmonic drive is produced. The final harmonic drive is experimentally tested to determine the life of its components when subjected to working loads. The methods used in this research include the part consolidation for the optimization of the system, transcription of 3D models to STL files that can be printed, polymer additive manufacturing and traditional quality control techniques to improve the design. Material models utilized in this project are commercial aluminum parts, 3D printer and plastic, and a low-voltage power motor. The complete set of results will give torque and speed reduction ratios that will be compared to those previously obtained by electronic simulations. This locates us a step ahead in the creation of an optimal process for additive manufacturing.
Leadership: A Critical Text, by Simon Western

Leadership continues to be a widely investigated construct explored by a number of academic traditions that span across social and behavioral science, management sciences, humanities, arts, and mos...
Calcium, vitamin D, dairy products, and risk of colorectal cancer in the Cancer Prevention Study II Nutrition Cohort (United States)

Objective: Calcium, vitamin D, and dairy product intake may reduce the risk of colorectal cancer. We therefore examined the association between these factors and risk of colorectal cancer in a large prospective cohort of United States men and women. Methods: Participants in the Cancer Prevention Study II Nutrition Cohort completed a detailed questionnaire on diet, medical history, and lifestyle in 1992–93. After excluding participants with a history of cancer or incomplete dietary information, 60,866 men and 66,883 women remained for analysis. During follow-up through 31 August 1997 we documented 421 and 262 cases of incident colorectal cancers among men and women, respectively. Multivariate-adjusted rate ratios (RR) were calculated using Cox proportional hazards models. Results: Total calcium intake (from diet and supplements) was associated with marginally lower colorectal cancer risk in men and women (RR = 0.87, 95% CI 0.67–1.12, highest vs lowest quintiles, p trend = 0.02). The association was strongest for calcium from supplements (RR = 0.69, 95% CI 0.49–0.96 for ≥500 mg/day vs none). Total vitamin D intake (from diet and multivitamins) was also inversely associated with risk of colorectal cancer, particularly among men (RR = 0.71, 95% CI 0.51–0.98, p trend = 0.02). Dairy product intake was not related to overall risk. Conclusions: Our results support the hypothesis that calcium modestly reduces risk of colorectal cancer. Vitamin D was associated with reduced risk of colorectal cancer only in men.
Tumor growth inhibition by intratumoral inoculation of defective herpes simplex virus vectors expressing granulocyte-macrophage colony-stimulating factor.

To evaluate the potential of defective herpes simplex virus (HSV) amplicon vectors as in vivo cytokine gene transfer vehicles for active immunotherapy, we generated a defective HSV vector that encodes the murine granulocyte–macrophage colony-stimulating factor (GM-CSF) gene, using a replication-defective HSV as helper virus. A variety of murine tumor cell lines were efficiently infected in vitro with the defective GM-CSF vector (dvGM), and this led to the synthesis and secretion of murine GM-CSF. In an established bilateral subcutaneous tumor model with Harding–Passey murine melanoma, unilateral intratumoral inoculation of dvGM significantly inhibited tumor growth of both the inoculated and noninoculated contralateral tumors. This tumor inhibition was dose-dependent and resulted in increased survival of the dvGM-treated mice. Inoculation of a lacZ-expressing defective vector had no effect on tumor growth. We conclude that this defective HSV vector system offers an effective method for cytokine gene delivery in vivo and that GM-CSF expression in tumors has antitumor activity.
Nanofluid bioconvection: interaction of microorganisms oxytactic upswimming, nanoparticle distribution, and heating/cooling from below

The aim of this paper is to develop a theory describing the onset of convection instability (called here nanofluid bioconvecion) that is induced by simultaneous effects produced by oxytactic microorganisms, nanoparticles, and vertical temperature variation. The theory is developed for the situation when the nanofluid occupies a shallow horizontal layer of finite depth. The layer is defined as shallow as long as oxygen concentration at the bottom of the layer is above the minimum concentration required for the bacteria to be active (to actively swim up the oxygen gradient). The lower boundary of the layer is assumed rigid, while at the upper boundary both situations when the boundary is rigid or stress free are considered. Physical mechanisms responsible for the slip velocity between the nanoparticles and the base fluid, such as Brownian motion and thermophoresis, are accounted for in the model. A linear instability analysis is performed, and the resulting eigenvalue problem is solved analytically using the Galerkin method.
Environmental DNA: Genetics Steps Forward When Traditional Ecological Surveys Fall Short

Ecologists go to tremendous lengths to determine whether species are present in an area, from visual surveys and traps to hidden cameras and expensive angling operations. But imagine the possibilit...
Outcomes following nonoperative and operative treatment for cervical disc herniations in National Football League athletes.

Study Design. Retrospective cohort study. Objective. To determine the performance-based outcomes in elite athletes of the National Football League (NFL) after a cervical disc herniation. Summary of Background Data. Because outcomes after the treatment of cervical disc herniations (CDH) in elite athletes are currently unknown, the treatment decisions for this injury in professional football players are often controversial. Methods. NFL players diagnosed with a CDH were identified through previously published protocols using team injury reports and newspaper archives. The "Performance Score" for each player was calculated on the basis of pertinent statistical data, before and after diagnosis of CDH. Data analysis was performed for players with at least a 2-year follow-up. Results. A total of 99 NFL athletes met the inclusion criteria. In the operative group, on average, 38 of 53 (72%) players successfully returned to play for 29 games over a 2.8-year period, which was significantly greater than that of the nonoperative group, in which only 21 of 46 (46%) players successfully returned to the field to play after treatment for 15 games over a 1.5-year period (P < 0.04). Performance scores and the percentage of games started were not statistically significantly different for either cohort, before and after treatment. Notably, defensive backs had a significantly poorer outcome after treatment for CDH than any other position, playing in only 10 games over a 1.2-year period compared with all others (P < 0.0008). Age at diagnosis demonstrated a negative effect on career longevity after treatment. Conclusion. The data in this study suggest that players have higher return-to-play rates and longer careers after operative treatment than players treated with nonoperative means. Although confounding variables such as concomitant cervical stenosis could have affected these data, these performance-based outcomes after surgical treatment for CDH are better than previously thought. Defensive backs have a poorer prognosis after CDH compared with players of all other positions.
Cell-Free Expression Systems: From Gene Circuits to Self-Assembly Processes in a Test Tube

Cell-free transcription-translation (TX-TL) systems are becoming powerful platforms to construct complex biological systems in vitro through the expression of DNA programs. Considerable efforts have been made to improve those systems in the past decade. Our laboratory has developed the most efficient and versatile in vitro E. coli TX-TL system to express synthetic or natural DNA programs encoding for self-assembly processes. Either in test tube reactions, in emulsion droplets or in liposomes, cell-free TX-TL reactions are now used for research studies ranging from elementary gene circuits to minimal cells.I will present our custom-made cell-free TX-TL system, its current capabilities and limitations. Recently we have shown that entire phages can be synthesized in cell-free TX-TL reactions from their genomes. The bacteriophage T7, composed of about 60 genes, is entirely synthesized in a single test tube reaction from its 40 kbp genomic DNA. Replication of the T7 DNA instructions occurs concurrently with phage expression and self-assembly. The phage phiX174 composed of a dozen of genes can also be synthesized from its genome. Encapsulated inside cell-sized phospholipid liposomes, the TX-TL system is used to construct a prototype of minimal cell. I will present this cell-free synthetic biology platform, our last experiments and how this system can be used to study the relationship between information and self-organization.
A cis-Element in the 5′ Untranslated Region of the Preproinsulin mRNA (ppIGE) Is Required for Glucose Regulation of Proinsulin Translation

Insulin production in pancreatic beta cells is predominantly regulated through glucose control of proinsulin translation. Previously, this was shown to require sequences within the untranslated regions (UTRs) of the preproinsulin (ppI) mRNA. Here, those sequences were found to be sufficient for specific glucose-regulated proinsulin translation. Furthermore, an element 40-48 bp from the 5' end of the ppI mRNA specifically bound a factor present in islets of Langerhans. Glucose-responsive factor binding to this cis-element exhibited temporal and glucose-concentration-dependent patterns that paralleled proinsulin biosynthesis. Mutating this cis-element abolished the ability of ppI mRNA UTRs to confer glucose regulation upon translation. Like the rat 5'UTR, the human ppI 5'UTR conferred glucose regulation of translation. However alternative splicing of the human 5'UTR that disrupts the cis-element abolished glucose-regulated translation. These data indicate that glucose regulation of cis-element/trans-acting factor interaction is a key component of the mechanism by which glucose regulates insulin production.
Prediction of the Comparative Reinforcement Values of Running and Drinking

The probability of free drinking and running in rats was controlled by sucrose concentration and force requirements on an activity wheel. Drinking and running were then made contingent on pressing a bar. Barpressing increased monotonically with the associated response probability, and equally for drinking and running. The results support the assumption that different responses of equal probability have equal reinforcement value.
Barium and radium in the Dead Sea

Abstract We have measured Ba in Dead Sea samples collected before and after the 1979 overturn, and 226 Ra in nine samples collected after the overturn. Before this overturn, Ba and the 226 Ra data measured by Chung and Craig [4] show that a distinct two-layer structure existed, with higher concentrations in the upper layer. After the overturn, both elements were uniformly distributed in the water column. The inventories of Ba and Ra calculated from these data are the same for the periods before and after the overturn. If the inventories were constant during the last meromictic phase then the input rate must be balanced by the removal rate, and a mass balance model can be constructed to estimate physical parameters based on known or deduced sources and sinks. The sources include inputs from the Jordan River, springs around the Dead Sea, and submerged springs or seepages, etc. The sinks include coprecipitation with aragonite, gypsum, precipitation of barite, coprecipitation of Ra with barite, particulate scavenging, and radioactive decay for Ra. Our data include measurements of Ba and 226 Ra in gypsum, aragonite and halite from the Dead Sea, as well as in some of the inflowing rivers and springs. The inclusion of particulate scavenging as a sink is a major element of the model. We find that, without inclusion of a Ba scavenging term in the deep water, the lake volume at the previous overturn as calculated from the Ba data would be unrealistically high in comparison with historical records. The inclusion of particulate scavenging for Ra in the model reduces the calculated duration of the last meromictic phase significantly. Our model excludes internal mixing between the upper and lower water masses. With this restriction, various sets of model parameters were calculated as a function of the Ra/Ba scavenging rate ratio. If the ratio is one, the calculated age of the last meromictic phase is about a hundred years. A substantial increase in the Ra input rate is required to balance the removal rate by particulate scavenging as well as decay. If the ratio is zero, i.e. no particulate scavenging for Ra, the age is about 260 years, as obtained by Stiller and Chung [2].
The data refinement calculator for Z specifications

One approach to data refinement is to take programs involving objects of some abstract data type and replace them by equivalent programs based on a concrete type. In [l] and [lo], techniques are provided for proving such refinements correct. In this article, however, data refinement is applied to specifications of progrums rather than programs themselves. In particular, the weakest (most general) specification of a concrete operation is calculated from the specification of the abstract operation and a posited relation between abstract and concrete values. Early work on proof methods for data refinement can be found in [3] and [6]. Use is made of the weakest precondition in [l]. The idea of calculating specifications is contained in [4,5]. The method presented here is designed for specifications expressed in the Z language [2]. Use is made of the weakest precondition of a specification [8], adapted from [9]. The next section explains what is meant by correctness in this form of data refinement. Section 3 reveals how data refinements can be calculated so that they are automatically correct. An example of data refinement calculation is presented in the final section.
Phytoestrogens β-Sitosterol and Genistein Have Limited Effects on Reproductive Endpoints in a Female Fish, Betta splendens

Phytoestrogens are produced by plants and may cause endocrine disruption in vertebrates. The present study hypothesizes that phytoestrogen exposure of female Siamese fighting fish (Betta splendens) may disrupt endogenous steroid levels, change agonistic behavior expression, and potentially also disrupt oocyte development. However, only the pharmacologic dose of β-sitosterol had a significant effect on opercular flaring behavior, while we did not find significant effects of β-sitosterol or genistein on steroids or gonads. These findings are in direct contrast with previous studies on the effects of phytoestrogens in female fish. Results of the current study support previous work showing that the effects of phytoestrogen exposure may be less acute in mature female B. splendens than in other fish.
Thermal control subsystem requirements and challenges for a responsive satellite bus

The traditional approach to satellite design is a customized and highly optimized satellite bus. The primary design driver is to minimize mass but often at the expense of schedule and non-recurring engineering costs. The result after years of development is a high performance system with minimal flexibility. Consequently, there is a need for responsive, small satellites that are able to accommodate different missions, changing threats, and emerging technologies for which the traditional development approach is unable to satisfy. Instead, systems must be modular and/or robust. One of the subsystems that will be challenging for the development of modular and/or robust architectures is the thermal control subsystem (TCS). To design a traditional TCS, virtually every aspect of the mission, the satellite, and the components must be known before an intense design program can be completed. However, the mission, payload, components, and requirements are largely unknown before mission initiation. To provide a baseline for the TCS design and to help bound the problem for the development of robust thermal systems, the range of external and internal heat loads for small satellites were evaluated. From this analysis, the realistic worst design cases were identified along with other requirements for robust thermal control systems. Finally, the paper will discuss the merits of various thermal architectures and the challenges associated with achieving the requirements for robust thermal control for responsive satellite buses.
Three-Dimensional Analysis of Cracks in Layered Transversely Isotropic Media

A general mathematical formulation to analyse cracks in layered transversely isotropic media is developed in this paper. By constructing the Green's functions, an integral equation is obtained to determine crack opening displacements when an applied crack face traction is specified. For the infinite body, the Green's functions have solutions in a closed form. For layered media, a flexibility matrix in the integral transformed domain is formed that establishes the relation between the traction and the displacement for a single layer; the global matrix is formed by assembling all of the flexibility matrices constructed for each layer. The Green's functions in the spatial domain are obtained by inversion of the Hankel transform. Finally, the crack opening displacement and the crack-tip opening displacement for a vertical planar crack in a layered transversely isotropic medium are obtained numerically by the boundary integral equation method.
Decreased Reg I expression underlies age-related impairment of glucose tolerance

Abstract Introduction: Diabetes mellitus has been shown to be inversely correlated with pancreatic Reg I gene expression. We hypothesized that with aging, endogenous Reg I expression decreases as glucose tolerance worsens in elderly rats. Methods: The effects of age were investigated by subjecting twelve- and one-month-old female Wistar rats (n = 5 per group) to intraperitoneal glucose tolerance tests (IPGTT, 1 gm/kg D-glucose). We also examined the role of Reg I in young animals by selective blockade of its expression. Monoclonal anti-Reg I antibody (2.5 mg/kg) was chronically infused into the circulation of young animals using subcutaneous osmotic pumps for 7 days; normal mouse IgG was used as a treatment control (n = 5 per group). Pancreatic mRNA and protein levels of Reg I were determined by real-time PCR and Western blot, respectively. Glucose levels were then measured and glucose area under the curve (GAUC) was determined. Results: GAUC was significantly lower in the younger experimental group than in the aged animals (P Conclusion: Decreased Reg I expression in aging rats contributes to their worsening glucose tolerance, suggesting that Reg I gene upregulation might improve glucose tolerance in the elderly.
Body temperature regulation in a desert lizard, Sauromalus obesus, under undisturbed field conditions.

Abstract 1. 1. Mean selected body temperatures (MSBTs), measured by radiotelemetry, are presented for 15 chuckwallas on 26 animal days. 2. 2. MSBT, during the period of activity, ranged from 37.3 to 39.8°C ( X = 38.8 ± 0.2 SE ° C ) while MSBTs, from the time lizards attained their first high set point to the time that solar radiation ceased, ranged from 36.1 to 39.6°C ( X = 38.3 ± 0.2 SE ° C ). 3. 3. On cloudy, cool days, animals could not maintain high Tbs because of the absence of solar radiation. 4. 4. On sunny March and April days, animals were active for 5–6 hr but Tb then fell rapidly to low levels. 5. 5. From late April to mid May, animals were active for 7–8 hr and Tbs did not fall as drastically because of higher Tbs after sunset. 6. 6. August was the time of year (for this study) when chuckwallas had the highest effective 24 hr Tb, but it was also the time when they had the shortest activity interval.
Analytical model of the nonlinear dynamics of cantilever tip-sample surface interactions for various acoustic atomic force microscopies

A comprehensive analytical model of the interaction of the cantilever tip of the atomic force microscope (AFM) with the sample surface is developed that accounts for the nonlinearity of the tip-surface interaction force. The interaction is modeled as a nonlinear spring coupled at opposite ends to linear springs representing cantilever and sample surface oscillators. The model leads to a pair of coupled nonlinear differential equations that are solved analytically using a standard iteration procedure. Solutions are obtained for the phase and amplitude signals generated by various acoustic-atomic force microscope (A-AFM) techniques including force modulation microscopy, atomic force acoustic microscopy, ultrasonic force microscopy, heterodyne force microscopy, resonant difference-frequency atomic force ultrasonic microscopy (RDF-AFUM), and the commonly used intermittent contact mode (TappingMode) generally available on AFMs. The solutions are used to obtain a quantitative measure of image contrast resulting from variations in the Young modulus of the sample for the amplitude and phase images generated by the A-AFM techniques. Application of the model to RDF-AFUM and intermittent soft contact phase images of LaRC-cp2 polyimide polymer is discussed. The model predicts variations in the Young modulus of the material of 24 percent from the RDF-AFUM image and 18 percent from the intermittent soft contact image. Both predictions are in good agreement with the literature value of 21 percent obtained from independent, macroscopic measurements of sheet polymer material.
Application of the Kalman Filter to Light Curves of Eclipsing Binaries

Recently Kopal (1975a, b, c, d) initiated a new approach to the analysis of the light curves of eclipsing binary systems in which the solution is based on transforming the problem from the conventional time-domain into the frequency-domain. Irrespective of the type of eclipse, the present formulation of the frequency approach requires that a set of quantitiesA 2m, called moments, be determined from the observations. It is the purpose of the present paper to describe a data interpolation and smoothing technique based on a version of the Kalman filter to pre-process observations and to determine the quantitiesA 2m in an optimal sense.
Mathematics Self-Efficacy and Mathematical Problem Solving: Implications of Using Different Forms of Assessment

Abstract The mathematics self-efficacy and problem-solving performance of 327 middle-school students were assessed using two forms of assessment (traditional multiple-choice vs. open-ended fill-in-the-blank). The purpose was to determine whether varying the assessment format would influence students' self-efficacy judgments or alter the relationship between self-efficacy and performance. No differences in self-efficacy resulted from the different forms of assessment Students who took the multiple-choice performance test obtained higher scores than did students who took the open-ended test The latter group had poorer calibration, that is, the degree to which students' judgments of their capability reflect their actual competence. This finding suggests that students' self-perceptions of their mathematics capability may be less accurate than has previously been reported or that students' familiarity with traditional assessment formats creates an expectancy of a performance task that is multiple choice in nat...
Brow/Upper Lid Anatomy, Aging and Aesthetic Analysis

The upper eyelid serves the important anatomic function of protecting the eye and rewetting the cornea to maintain vision. The complex dynamic action of the upper eyelid explains its relatively complex anatomy. The brow has an important supportive role. Studies have revealed facial characteristics perceived as youthful and aged, and the anatomic basis of these changes is defined at many levels. Characteristic aging changes in the upper eyelid and brow create an appearance of aging and opportunities for functional and aesthetic improvement.
Statistical mechanics of light elements at high pressure. V Three-dimensional Thomas-Fermi-Dirac theory

A numerical technique for solving the Thomas-Fermi-Dirac (TED) equation in three dimensions, for an array of ions obeying periodic boundary conditions, is presented. The technique is then used to calculate deviations from ideal mixing for an alloy of hydrogen and helium at zero temperature and high presures. Results are compared with alternative models which apply perturbation theory to calculation of the electron distribution, based upon the assumption of weak response of the electron gas to the ions. The TFD theory, which permits strong electron response, always predicts smaller deviations from ideal mixing than would be predicted by perturbation theory. The results indicate that predicted phase separation curves for hydrogen-helium alloys under conditions prevailing in the metallic zones of Jupiter and Saturn are very model dependent.
Legitimating war by victimization: state-corporate crime and public opinion

This article argues that the ideological use of victimization helps legitimate the state-corporate crime of aggressive war. This contributes to the emerging criminology of war by offering a theoretical framework to better understand how state and corporate actors legitimate criminal military action. We argue that politicians and other elite figures promote a sense of national victimization that is amplified by the news media. We partially test our theory by measuring the association between the incidence of terror victimization ideas in the news and public support for the U.S. “war on terror.” We find some evidence of relationships between our Terrorism Victimization Index and both victimization worry and aggressive war support.
The influence of verbal ability and metamemory on future recall

Summary. This study determines whether items from a metamemorial questionnaire would better predict recall performance than standardised measures of general verbal ability. Thirty-two children, separated into high and average verbal ability groups, were administered a metamemory test and, one week later, two prose and free-recall tasks. The results indicated that ability group differences were limited to certain dependent measures (i.e., mental effort, knowledge about strategies, equivalence/non-equivalence of strategy resources and strategy applicability). Most importantly, a stepwise regression analysis indicated that metamemory scores were more likely to predict the future recallability of material than measures of language ability (i.e., verbal IQ, reading and language achievement). Results are discussed in terms of children's “awareness” of the combined influences of memory variables and of the awareness of executive routines as a more important determinant of future recall than language ability.
The laparoscopic management of ovarian carcinoma: preliminary observations and suggested protocols

The laparoscopic management of seven women with primary ovarian cancer is described. One had stage I disease, four had stage IIIB and IIIC disease, and two were restaged after suboptimal primary operations. Both patients who were restaged had aortic lymph node metastasis. All patients were left with either no residual or minimal residual disease. The mean anaesthetic time was 4.25 h, the average blood loss 542 ml, the median hospital stay 3 days, and there were no surgical complications. Five patients received chemotherapy prior to discharge. The laparoscopic management of ovarian cancer is discussed in the light of this necessarily anecdotal experience, and the widely held view that laparoscopic surgery is contraindicated in women with suspected ovarian cancer is shown to be untenable. Protocols for the laparoscopic management of patients with early and advanced stage disease are outlined and discussed.
Constitutive expression of BCL‐XL in the T lineage attenuates collagen‐induced arthritis in Bcl‐XL transgenic mice

Objective To determine if inhibition of T cell apoptosis through constitutive expression of Bcl-XL in the T lineage influences inflammatory arthritis in the mouse collagen-induced arthritis (CIA) model. Methods The incidence and severity of arthritis were quantified in Bcl-XL transgenic mice and nontransgenic littermates after immunization with type II collagen (CII). To correlate T cell responses with disease phenotype, antigen-specific T cell proliferation was measured by 3H-thymidine incorporation. Apoptosis and cell cycle progression were analyzed by flow cytometry using propidium iodide. Production of CII-specific interferon-γ (IFNγ), interleukin-5 (IL-5), and IL-10 was determined by enzyme-linked immunosorbent assay. Results Disease severity in CIA was significantly attenuated in Bcl-XL transgenic mice compared with their nontransgenic littermates. Inhibition of CIA was associated with decreased T cell apoptosis, delayed cell cycle progression, and reduced IFNγ production. Conclusion Rather than promoting inflammation, inhibition of apoptosis by expression of the Bcl-XL protein in the T lineage attenuates disease progression in CIA, probably through inhibition of IFNγ production.