cssi/SciSciGPT-SciSciNet huggingface dataset:
Design of Microstructures in Sol-Gel Processed Silicates

More and more, oxides and glasses are being prepared by chemical routes (1). In some cases, chemical routes are used to prepare ideal oxide powder compacts (2,3). These compacts, in turn, densify to defect free polycrystalline ceramics (4). In cases dealt with in this paper, chemical routes are used to generate oxides in a porous preform of their final geometry. The geometries of interest are fibers (5), thin films (6) and shapes called monoliths (7,8).
Exploring the Values of U-Commerce from the Customers' Perspective

U-commerce has emerged as the next weave of commerce. It presents a new channel/medium for commerce and shows great promises for future applications and potential markets. This study aims to uncover the values of u-commerce from the customers’ perspectives, to understand what customers desire and expect from u-commerce, and to identify the functions and features they want in u-commerce. Value refers to what one desires to achieve. The scenario-based method was adopted by using video clips to illustrate applications of u-commerce for customers and to provide subjects with the necessary background information and knowledge about the emerging u-commerce phenomenon. The Value-Focused Thinking approach, which provides a systematic way to articulate and organize values, was applied to determine the values of ucommerce to users and define the relationships among those values. The result of this study is a means-ends objective network that depicts the fundamental objectives that will drive customers to use or deploy u-commerce. The network also illustrates how the fundamental objectives can be achieved through means objectives. We further propose a research model that categorizes the ten fundamental objectives into four value sub-components – sociopsychological, economic, functional, and product values. The derived means-ends objective network and value model can serve as a conceptual foundation for future research in u-commerce and provide useful guidelines to practitioners in developing and implementing u-commerce.
ASSIMILATION: a strategy for implementing self-reorganizing knowledge bases

Assimilation is a process by which a knowledge base restructures itself to improve the organization of and access to information in the base. This paper presents a strategy for implementing assimilation in propositional knowledge bases which distinguish between the axioms of the system's knowledge (called the context) and the derived consequences of those axioms (called the belief space). The strategy in question takes advantage of housekeeping phases in which the system discards accumulated clutter to discover useful patterns of access on the basis of which the context can be reorganized. Unused axioms are replaced by their more useful consequences; derivable generalizations that shorten common inference paths are added to the belief space.
An Achievable Rate Region for the K-Receiver Two Nested Groupcast DM Broadcast Channel and a Capacity Result for the Combination Network

Using an order-theoretic approach, a novel achievable rate region is obtained for the $K$ -receiver discrete memoryless broadcast channel with two nested messages, one message desired by all receivers and the other desired by a subset of the receivers. When specialized to the combination network this inner bound is shown to achieve the capacity region when all but two receivers desire both messages.
Twitter diplomacy between India and the United States: Agenda-building analysis of tweets during presidential state visits:

This analysis examines Twitter comments from the United States and India (N = 11,532) during reciprocal state visits by Prime Minister Narendra Modi and President Barack Obama. Results show the mos...
Unstable Growth of Branched Cracks

The growth behavior of branched cracks embedded in an elastic plate subjected to some simple loading conditions is studied. The strain energy density criterion is applied to determine the conditions of unstable fracture starting from the crack tips. Considered are symmetrically and asymmetrically branched cracks, and crack branching from an elliptical crack. The most vulnerable crack branch to initiate unstable fracture, the corresponding critical load and the initial fracture path are determined. The severity of a branched crack is also discussed and compared to the results of a single crack with the same overall length. Comparisons on the critical loads are made for the various branched crack configurations.
Spin coherence as a function of depth for high-density ensembles of silicon vacancies in proton-irradiated 4H–SiC

Abstract Defects in wide-band-gap semiconductors provide a pathway for applications in quantum information and sensing in solid state materials. The silicon vacancy in silicon carbide has recently emerged as a new candidate for optically controlled spin qubits with significant material benefits over nitrogen vacancies in diamond. In this work, we present a study of the coherence of silicon vacancies generated via proton irradiation as a function of implantation depth. We show clear evidence of dephasing interactions between the silicon vacancies and the spin environment of the bulk crystal. These results will inform further routes toward fabrication of scalable silicon carbide devices and studies of spin interactions in high-density ensembles of defects.
Interaction of the oncoprotein transcription factor MYC with its chromatin cofactor WDR5 is essential for tumor maintenance

The oncoprotein transcription factor MYC is overexpressed in the majority of cancers. Key to its oncogenic activity is the ability of MYC to regulate gene expression patterns that drive and maintain the malignant state. MYC is also considered a validated anticancer target, but efforts to pharmacologically inhibit MYC have failed. The dependence of MYC on cofactors creates opportunities for therapeutic intervention, but for any cofactor this requires structural understanding of how the cofactor interacts with MYC, knowledge of the role it plays in MYC function, and demonstration that disrupting the cofactor interaction will cause existing cancers to regress. One cofactor for which structural information is available is WDR5, which interacts with MYC to facilitate its recruitment to chromatin. To explore whether disruption of the MYC-WDR5 interaction could potentially become a viable anticancer strategy, we developed a Burkitt's lymphoma system that allows replacement of wild-type MYC for mutants that are defective for WDR5 binding or all known nuclear MYC functions. Using this system, we show that WDR5 recruits MYC to chromatin to control the expression of genes linked to biomass accumulation. We further show that disrupting the MYC-WDR5 interaction within the context of an existing cancer promotes rapid and comprehensive tumor regression in vivo. These observations connect WDR5 to a core tumorigenic function of MYC and establish that, if a therapeutic window can be established, MYC-WDR5 inhibitors could be developed as anticancer agents.
141 – Reversion Method

Publisher Summary This chapter discusses yield and procedure of Reversion method. It is applicable to force nonlinear ordinary differential equations. It yields a local approximation. It is found that to derive the method, one assumes a certain parameter is small and develops a perturbation expansion in that parameter. It is suggested to use the formulae obtained by this method when the parameter is equal to one. It is supposed that the general nonlinear differential equation whose solution one wish to approximate near the initial value is given by D1y + D2y2 + ⋅⋅⋅ + D5y5 + ⋅⋅⋅ = kΦ(x) where the {Di} represent differential operators.
Submucosal Supernumerary Smooth Muscle Coat: A Common Histologic Finding in Mowat-Wilson Syndrome With or Without Hirschsprung Disease.

BackgroundMowat–Wilson syndrome (MWS) is a multiorgan system disorder caused by ZEB2 (zinc finger E-box-binding homeobox 2) mutations or deletions. One common manifestation is constipation, and app...
Factors influencing bred beef heifer sale prices in a sequential auction

ABSTRACT Objective This study determines bred heifer auction price response as the number of available bred heifers for purchase decreases while controlling for reproductive management characteristics and feeder cattle prices. Materials and Methods The data used in this study came from a bred heifer sale located on the Tennessee and Kentucky state line from 2008 through 2017, and a hedonic pricing model was estimated that considered months pregnant, breed, AI pregnancy, lot size, and timing of when the heifer was purchased in the sale. Results and Discussion We found that months pregnant, lot size, sale month, and heifer price affected the sale price of bred heifers. We also can concluded that bred heifer sale price increased until about 49% of all heifers available in the sale were purchased. Implications and Applications Beef cattle producers frequently buy and sell cattle through auction markets. However, more information on how timing of placement in the sale affects bred heifer values could be helpful in informing buyers on bid timing to purchase replacements at lower costs. Results suggest that bidding earlier, or waiting to bid later in the sale, could result in lower purchase prices of bred heifer when holding reproductive characteristics and feeder cattle prices constant. This is a unique study that provides insight into bidding timing for buyers to consider when purchasing bred heifers. These strategies could be helpful in selecting lots to bid on that have desired attributes but are being sold when prices are lowest.
Towards Identification and Mitigation of Task-Based Challenges in Comparative Visualization Studies

The effectiveness of a visualization technique is dependent on how well it supports the tasks or goals of an end-user. To measure the effectiveness of a visualization technique, researchers often use a comparative study design. In a comparative study, two or more visualization techniques are compared over a set of tasks and commonly measure human performance in terms of task accuracy and completion time. Despite the critical role of tasks in comparative studies, the current lack of guidance in existing literature on best practices for task selection and communication of research results in evaluation studies is problematic. In this work, we systematically identify and curate the task-based challenges of comparative studies by reviewing existing visualization literature on the topic. Furthermore, for each of the presented challenges we discuss the potential threats to validity for a comparative study. The challenges discussed in this paper are further backed by evidence identified in a detailed survey of comparative tree visualization studies. Finally, we recommend best practices from personal experience and the surveyed tree visualization studies to provide guidelines for other researchers to mitigate the challenges. The survey data and a free copy of the paper is available at https://osf.io/g3btk/
Passive Multistatic Radar Imaging with Prior Information

Our work extends the framework of Generalized Wirtinger Flow (GWF) [19] to incorporate prior information regarding the signal of interest (which is scene reflectively in our case). For interferometric multi-static radar measurements, we consider a linear-deterministic-discrete lifted forward model. Several structures on the signal can prove beneficial in the recovery process. In particular, we leverage the sparse structure of the unknown signal and show through numerical simulations that sparsely constrained GWF converges at a faster rate than a recovery method that does not acknowledge sparse structure.
Visual prototypes in the ventral stream are attuned to complexity and gaze behavior.

Early theories of efficient coding suggested the visual system could compress the world by learning to represent features where information was concentrated, such as contours. This view was validated by the discovery that neurons in posterior visual cortex respond to edges and curvature. Still, it remains unclear what other information-rich features are encoded by neurons in more anterior cortical regions (e.g., inferotemporal cortex). Here, we use a generative deep neural network to synthesize images guided by neuronal responses from across the visuocortical hierarchy, using floating microelectrode arrays in areas V1, V4 and inferotemporal cortex of two macaque monkeys. We hypothesize these images (“prototypes”) represent such predicted information-rich features. Prototypes vary across areas, show moderate complexity, and resemble salient visual attributes and semantic content of natural images, as indicated by the animals’ gaze behavior. This suggests the code for object recognition represents compressed features of behavioral relevance, an underexplored aspect of efficient coding. Visual recognition depends on the ability to extract specific shape and colour features from complicated natural scenes. Here, the authors show that neurons along the object-recognition cortical pathway encode information-concentrating features of moderate complexity and of behavioural relevance.
Singlet–triplet competition in the low-lying energy states of C4O4−n S n (n = 1–3) molecules

Cyclobutanetetrone, C4O4, has a triplet ground state, although the ground state of C4S4 is singlet. This computational study focuses on the mono-, di-, and trithiosquarate, C4O4−n S n (n = 1–3), molecules as transition stages between the two ending points (C4O4 and C4S4), and investigates the trends for the changes in the energies, geometry, partial atomic charges, partial spin densities, as well as orbital energies of the four low-lying electronic states. As the number of the sulfur atoms is increasing, the singlet spin state becomes energetically more and more preferred. For C4O3S molecule, where only one oxygen atom is substituted by sulfur, the CCSD(T) calculations predict a triplet ground state, but the error of the calculations is most likely higher than the calculated 0.5 kcal/mol singlet–triplet energy gap.
Fracture toughness behavior of unaged beta-III titanium

The dynamic fracture toughness behavior of unaged Beta-III (Ti-10.2 Mo-6Zr-4.5Mo) titanium has been investigated. Both solution treatment practice and subsequent test temperature have been found to affect the fracture toughness. Decreasing the solution treatment temperature from 1255 to 1005 K generally led to a decrease in the fracture toughness over the entire range of test temperatures investigated. In addition, decreasing the test temperature from 473 to 77 K also resulted in lower fracture toughness. These reductions in fracture toughness have been shown to be related to the introduction of increasing amounts of a localized shear fracture mode with both decreasing solution and test temperature. Based on these observations, a model has been proposed which describes the stress/strain conditions at the tip of a propagating crack that appear to enhance shear fracture. Finally, it has been suggested that the principal metallurgical variable controlling the choice of fracture mode transition from either dimple to cleavage or dimple to shear dimple in unaged metastable β titanium alloys is the primary deformation mechanism. Twinning tends to promote shear instability while slip may be associated with low temperature cleavage crack propagation.
Molecular nanoelectronics for label free DNA analysis

An ultrasensitive nanogap junction is developed for label-free biomolecular detection. The nanogap junction can minimize the effects of electrode polarization. Without any label, dielectric detection of DNA hybridization is accomplished: the 70% and 12% changes of capacitance after hybridization were accomplished at 100 Hz for 10 /spl mu/M and 10 fM concentrations of target DNA, respectively. The nanogap junction-based dielectric DNA detection method and the batch fabrication method of nanogap junctions might able to change the paradigm of functional genomics and proteomics.
Seeking Openings of Already Closed Student-Teacher Relationships

Upon beginning his tenure as a high school teacher in an all-boys Catholic school, Eduardo Lopez reports that “during the first weeks, I came across such powerful resistance that I was unsure and confused as to how to teach.” Students in my class “informed me that teachers had been unable to control them and it would be only a matter of time before I, too would leave the school.” Lopez countered the students’ challenge with efforts to establish classroom order, and the students — in turn — dismissed Lopez as a “police officer” en route to organizing successful disruptions of the class. The clash of discipline and resistance peaked one day, and Lopez traces the alteration of his pedagogy to this moment. Even though many students were talking in class, he singled out one who had been continuously disruptive and told the student to leave. Students protested, but Lopez was resolute. The student picked up his bag and began to leave at which point Lopez ordered him to put down his bag. The student refused, and a tussle between student and teacher ensued. Upon seeing himself performing in ways that profoundly violated his own principles, Lopez abandoned the struggle, now seeing himself in just the ways the students had described him. After days of soul searching, Lopez apologized to the students for his heavy-handed tactics and told them he cared too much about them to continue treating them punitively. He told them he would never kick a student out of class again. He switched his pedagogy to focus on stereotypes, racism, and economic inequality and asked students to write weekly papers on topics of their choosing. The students stopped opposing everything Lopez did and began writing essays on Latina/o and African-American leaders who had worked as agents to counteract oppression. This is an extreme example where relationships between the student and teacher were closed off to begin with, but were opened — partly — by the pedagogical strategy of the teacher.
Our Lady of Class Struggle: the Cult of the Virgin Mary in Haiti

Our Lady of Class Struggle: The Cult of the Virgin Mary in Haiti. Terry Rey. Trenton. NJ, and Asmara, Eritrea: Africa World Press, Inc., 1999. + 362 pp. (Paper US$21.95)
Generic alendronate use among Medicare beneficiaries: are Part D data complete?

Background Generic alendronate was approved in the United States on February 6, 2008. Medicare beneficiaries might pay for generic alendronate out-of-pocket without having claims submitted, resulting in misclassification of generic alendronate use in Medicare data. Objectives To estimate the completeness of generic alendronate use in 2008 Medicare Part D data; to identify factors associated with staying on branded alendronate versus switching to a generic product. Methods We identified Medicare beneficiaries highly adherent (medication possession ratio ≥80%) with branded alendronate during 1/1/06–2/6/07 (“2007 cohort”) and during 1/1/07–2/6/08 (“2008 cohort”). The outcome was medication status at the end of follow-up (12/31/2007 or 12/31/2008), classified as continued branded alendronate, switched to generic alendronate, switched to another bisphosphonate or presumed discontinued bisphosphonate therapy. Cox regression estimated the hazard ratio (HR) for discontinuation in 2008 compared to 2007. Multinomial logistic regression identified factors associated with medication status for the 2008 cohort. Results Among 15 310 subjects using branded alendronate in the 2008 cohort, 81% switched to generic alendronate. The proportion presumably discontinuing bisphosphonate therapy was 8.9% in 2008 compared to 7.7% in the 2007 cohort (adjusted HR, 1.15; 95% confidence interval, 1.05, 1.26). Factors associated with staying on branded alendronate in 2008 were higher income, eligibility for a low income subsidy and use of Fosamax® plus vitamin D. Conclusion Evaluation of Medicare prescription drug data suggests that the amount of missing claims for generic alendronate in 2008 was not substantial, and misclassification of exposure in studies examining alendronate use post-generic product availability should be minimal. Copyright © 2012 John Wiley & Sons, Ltd.
Detection and identification of Treponema hyodysenteriae by using oligodeoxynucleotide probes complementary to 16S rRNA.

Oligodeoxynucleotide probes (17 and 28 bases long) complementary to a unique region of Treponema hyodysenteriae 16S rRNA were developed. These probes bound specifically to partially purified rRNA and whole-cell rRNA of T. hyodysenteriae. No binding to partially purified rRNA or whole-cell rRNA of Treponema innocens, Treponema succinifaciens, Treponema bryantii, or Escherichia coli occurred under stringent conditions. The 28-base probe was 5 to 10 times more sensitive than the 17-base probe when hybridized with T. hyodysenteriae rRNA. The 28-base probe detected T. hyodysenteriae in the feces of experimentally inoculated pigs exhibiting clinical signs of swine dysentery. Images
Abstract 82: A comprehensive characterization of cholecalciferol supplementation induced changes in the vitamin D3metabolic pathway in metastatic colorectal cancer patients

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Epidemiological data suggest that vitamin D3 deficiency plays a role in the pathogenesis and progression of human colorectal adenomas and adenocarcinomas. We have characterized the changes in plasma vitamin D3 metabolites (25-D3, 24,25-D3 and 1,25-D3), PTH and vitamin D3 binding protein (VDBP) levels, and peripheral blood mononuclear cells (PBMC) CYP24A1 activity in metastatic colorectal cancer (CRC) patients receiving 2000 IU of oral cholecalciferol daily over a 12 month period. Plasma samples were collected on day 0, 14, 30, 60, 90, 180, 270 and 360. Serum 25-D3 and 24,25-D3 were measured by LC/MS/MS method; plasma PTH and 1,25-D3 levels were determined by RIA. Plasma VDBP levels were measured by ELISA. PBMC CYP24A1activity was determined by HPLC method. A total of 50 CRC patients completed the study. Baseline 25-D3 were significantly influenced by season (p= 0.0145) . Baseline plasma 25-D3 levels were 30ng/mL were 74.82 ± 27.02 and 56.46 ± 18.10pg/mL, respectively (p>0.05). Baseline PBMC CYP24A1activity was not affected by baseline 25-D3 levels. The increase in serum 25-D3 and 24,25-D3 levels during cholecalciferol treatment was characterized by an initial phase of rapid increase (between day 1 and day 90) followed by a phase of stable plasma 25-D3 and 24,25-D3 levels. A linear relation between plasma 25-D3 and 24,25-D3 was observed at baseline and during cholecalciferol supplementation (r2 = 0.55). No consistent changes in PBMC CYP24A1 activity was observed after 90 days of cholecalciferol treatment. The plasma 24,25-D3/25-D3 ratio at day 60 and 90 of cholecalciferol treatment was weakly correlated (r2=0.03 and 0.06, respectively) to changes in plasma 25-D3 levels. No CRC patient subsets with disproportional increase in plasma 24,25-D3 levels relative to 25-D3 levels during cholecalciferol treatment were identified suggesting that that variable 25-D3 responses cannot be explained by increased 24-hydroxylation. The increase in 1,25-D3 was linear, remained below 100pg/mL and did not correlate with plasma 25-D3 levels. A decrease in plasma PTH levels from 62.83 ± 24.84 to 41.61 ± 18.42 pg/mL was observed after 2 months of cholecalciferol supplementation (p<0.0001). Plasma VDBP protein levels were inconsistent across the study duration; no specific patterns or correlations with 25-D3 or 1,25-D3 could be identified. In summary, vitamin D3 deficiency, defined as 25-D3 <30 ng/mL, is prevalent in metastatic CRC patients. Furthermore, CYP24A1-mediated catabolism of 25-D3 to 24,25-D3 does not appear to be a major determinant of systemic 25-D3 levels. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 82.
Observations on the Separation and Measurement of Inorganic Iodine in Rat Thyroid Glands

Several methods for separating thyroidal inorganic from organic radioiodine have been directly compared, and the recoveries of inorganic iodine which they afford have been assessed. Complete or nearly complete recovery of inorganic I131 was provided by paper electrophoresis, 1-hr dialysis, or acid-precipitation of thyroid homogenates. In thyroid glands uniformly labeled with I131, lowest values for inorganic I131, indicating most effective separation and/or least artifactual deiodination, were obtained with paper electrophoresis. Slightly higher values were found with 1-hr dialysis. Substantially higher values were obtained with trichloroacetic and perchloric acid precipitation, chromatography, and iodate oxidation. The greater values found with dialysis and with acid-precipitation procedures than with electrophoresis resulted from the inclusion in their presumed inorganic fraction of iodinated compounds, presumably iodopeptides, which remained near the origin of chromatograms and electrophoretograms. The...
Lead-Free Solder-Joint Reliability of a Photonic Device Under Transient and Steady State Loadings

Three solders, 63wt%Sn-37wt%Pb, 80wt%Au-20wt%Sn and 95.5wt%Sn-3.9wt%Ag-0.6wt%Cu, are studied as interconnect materials in a vertical-cavity surface-emitting laser, or VCSEL. While the Au-Sn alloy is a lead-free solder material that had been previously identified as a candidate material for this device, the Sn-Ag-Cu solder (henceforth SAC solder) is presently the leading lead-free solder candidate for numerous packaging types. In the present study, thermal-structural analysis evaluates the solder alloys in the context of in-service operating conditions. Specifically, the thermal analysis determines the in-service temperature distributions, as influenced by each solder alloy, due to power generation within the VCSEL and due to convective boundary conditions. Subsequently, these thermal profiles are used as the thermal loads in an evaluation of the creep response in the solder materials. Emphasis is placed on the relaxation of stresses and on the creep strains developed during a 24 hour power-on condition.Copyright © 2003 by ASME
Protein quality of homemade weaning food mixtures: 2. Amino acid composition versus biological methods

Protein quality of fourteen different homemade weaning food mixtures, already evaluated by biological procedures, was also estimated on the basis of amino acid composition. Amino acids were determined by ion‐exchange chromatography with the exception of tryptophan, which was estimated from published values for the component ingredients. Amino acid scores were calculated using the FAO/WHO (1973) pattern as well as the new FAO/WHO/UNU (1986) reference patterns for the infant and young child and were compared with the protein values determined biologically. Agreement was high. In addition, comparison was made between estimated intakes and the newly published requirement values for essential amino acids. It was concluded that all mixtures would meet protein and amino acid needs if they were supplied at sufficient levels to meet food energy needs.
The inhibition of nucleic acid-binding proteins by aurintricarboxylic acid.

Abstract Qβ replicase, Escherichia coli RNA polymerase, and T7 RNA polymerase are inhibited by low concentrations of the dye aurintricarboxylic acid (ATA). In each case initiation by the enzyme was preferentially inhibited. The elongation of initiated polynucleotide chains by Qβ replicase was insensitive to ATA in the range of concentrations required to inhibit initiation. Treatment of Qβ replicase, RNA polymerase and lac repressor with ATA prevented enzymemediated binding of the templates to nitrocellulose filters. We propose that the inhibitor combines with the template binding site of these proteins to prevent initiation.
Co-Ordinated Rendezvous of Unmanned Air Vehicles to a Formation Using a Sliding Mode Approach

A method for the co-ordinated rendezvous of a team of unmanned air vehicles (UAVs) to a formation through the use of sliding mode control is presented. The focus of this work is on the scenario where three ‘follower’ UAVs must rendezvous in a desired formation about a ‘Leader’ UAV in a finite time. An assumption is made that each UAV only receives knowledge of the bounds of the manoeuvres that the other UAVs are performing. By not requiring manoeuvre information to be constantly available, a level of robustness to possible communication outages between UAVs is obtained. The proposed method also guarantees that the formation will be achieved in a finite time through the use of a concept of sliding mode terminal guidance (SMTG). SMTG takes advantage of the finite-time reaching phase of sliding mode to ensure that any desired constraint can be fulfilled in a finite time.
Investigations of autogenous and semi-autogenous grinding in tumbling mills

Abstract A model based on the specific rates of breakage of each size in a mill as affected by balls and large lumps has been developed. Three mechanisms of breakage are recognized: ‘normal’ fracture of smaller sizes by balls and larger pebbles, ‘chipping’ of raw feed to give rounded pebbles and ‘abrasion’ from the surfaces of pebbles. A tracing technique was developed to distinguish these contributions to autogenous breakage in batch grinding tests. It was found that the accumulation of finer material strongly cushions the impact between pebbles and pebbles and pebbles and balls. Empirical relations were developed to describe this cushioning effect. It was also found that chipping breakage is first order for short times of grinding. The mathematical model lumps fracture and chipping in a single contribution and considers the material as if it were a mixture of fast- and slow-breaking components. Breakage rates and primary breakage distributions measured on an ore in batch tests were used to predict the performance of a 1.8-m diameter pilot-scale mill, and predictions compared to the pilot-scale data on the same ore.
Adaptation of the spore discharge mechanism in the basidiomycota.

Background Spore discharge in the majority of the 30,000 described species of Basidiomycota is powered by the rapid motion of a fluid droplet, called Buller's drop, over the spore surface. In basidiomycete yeasts, and phytopathogenic rusts and smuts, spores are discharged directly into the airflow around the fungal colony. Maximum discharge distances of 1–2 mm have been reported for these fungi. In mushroom-forming species, however, spores are propelled over much shorter ranges. In gilled mushrooms, for example, discharge distances of <0.1 mm ensure that spores do not collide with opposing gill surfaces. The way in which the range of the mechanism is controlled has not been studied previously.
Diagnostic Accuracy of a Bedside D-dimer Assay and Alveolar Dead-Space Measurement for Rapid Exclusion of Pulmonary Embolism: A Multicenter Study

ContextA previous study suggested that the combination of a normal D-dimer assay and normal alveolar dead-space fraction is a highly sensitive screening test for pulmonary embolism (PE).ObjectiveTo determine if the combination of a normal alveolar dead-space fraction (volume of alveolar dead space/tidal volume ≤20%) and a normal whole-blood agglutination D-dimer assay can exclude PE in emergency department (ED) patients.DesignProspective, noninterventional study conducted in 1998-1999. Study data were obtained prior to standard testing for PE, consisting of radionuclide lung scanning or contrast-enhanced computed tomography and 6-month follow-up plus selective use of venous ultrasonography and pulmonary angiography. Imaging studies were interpreted by blinded observers.SettingSix urban teaching hospitals in the United States.PatientsA total of 380 hemodynamically stable ED patients aged 18 years or older with suspected acute PE.Main Outcome MeasuresSensitivity and specificity for PE with a positive test defined as having either alveolar dead-space fraction or D-dimer assay results abnormal. Alveolar dead-space fraction was determined by subtracting airway dead space from physiological dead space (determined using the modified Bohr equation) and D-dimer assay, assayed at bedside using 20 µL of arterial blood.ResultsPulmonary embolism was diagnosed in 64 patients (16.8%), of those 20 had an abnormal D-dimer assay result, 3 had an abnormal alveolar dead-space fraction, 40 had abnormal results in both, and 1 had normal results for both tests. The sensitivity for diagnosis of PE was 98.4% (95% confidence interval [CI], 91.6%-100.0%). Among the 316 patients without PE, both D-dimer and dead-space results were normal in 163, for a specificity of 51.6% (95% CI, 46.1%-57.1%). Posterior probability of PE with normal results on both tests was 0.75% (95% CI, 0%-3.4%).ConclusionIn this multicenter study of ED patients, a normal D-dimer assay result plus a normal alveolar dead-space fraction was associated with a low prevalence of PE.
Effectiveness of atomic and polyatomic primary ions for organic secondary ion mass spectrometry

Abstract With the increased application of polyatomic primary ions for organic secondary ion mass spectrometry, a method to compare the performance of the various available projectiles is needed. In this work, primary ion performance was evaluated based on analyte-specific secondary ion yield, the amount of fragmentation, and the amount of metastable decay induced by each primary ion. These measurements were used to construct a projectile efficiency number for each primary ion applied to a specific analyte. An organic acid, phospholipids, and alkyl sulfates, prepared as multilayer and monolayer surfaces were analyzed with various atomic and polyatomic primary ions. It was found that polyatomic primary ions are best suited for multilayer organic samples whereas atomic primary ions are most effective for monolayer organic samples. Results are compared to other studies that measure the ion formation efficiency of various primary ions.
Primary Elections and Candidate Ideology: Out of Step with the Primary Electorate?

This article draws on a new dataset of House primary- and general-election outcomes (1956–98) to examine the relationship between primary elections and candidate ideology. We show that, like presidential candidates, congressional candidates face a strategic-positioning dilemma: should they align themselves with their general- or primary-election constituencies? Relative to general-election voters, primary voters favor more ideologically extreme candidates. We show that congressional candidates handle the dilemma by positioning themselves closer to the primary electorate. This article thus supports the idea that primaries pull candidates away from median district preferences.
An experimental investigation of mixing mechanisms in shock-accelerated flow

An experimental investigation of mixing mechanisms in a shock-induced instability flow is described. We obtain quantitative two-dimensional maps of the heavy-gas (SF 6 ) concentration using planar laser-induced fluorescence for the case of a shock-accelerated cylinder of heavy gas in air. The instantaneous scalar dissipation rate, or mixing rate, Χ, is estimated experimentally for the first time in this type of flow, and used to identify the regions of most intense post-shock mixing and examine the underlying mechanisms. We observe instability growth in certain regions of the flow beginning at intermediate times. The mixing rate results show that while these unstable regions play a significant role in the mixing process, a large amount of mixing also occurs by mechanisms directly associated with the primary instability, including gradient intensification via the large-scale strain field in a particular non-turbulent region of the flow.
An Introduction to Some Historical Governmental Weather Records of China

Abstract Some historical weather records of China in the governmental archives are discussed. The records in the pre-Qing period (before 1636) am briefly summarized and their use for the reconstruction of past climate is assessed. The more-elaborate weather records of the Qing dynasty, the Clear and Rain Records and the Inches of Rain and Snow, are examined in more detail.
Rationalization of esthetic restorative dentistry based on biomimetics.

Abstract: The exponential progressivism that characterizes the current decade often comes with substantial financial implications. Dental care is not spared by this phenomenon. However, new generations of concepts emerging from biomimetics provide the operator with the ability to restore the biomechanical, structural, and esthetic integrity of teeth. The development of adhesion and the evolution of porcelain veneers constitute striking examples of this nascent process. Indications for bonding porcelain are extending to more perilous situations (crown-fractured incisors, nonvital teeth), resulting in considerable improvements, comprising both the medical-biologic aspect (economy of sound tissues and maintenance of tooth vitality) and the socioeconomical context (decrease of costs compared to traditional and more invasive prosthetic treatments). CLINICAL SIGNIFICANCE: In the bonded porcelain veneer and its extensions, restorative dentistry has found new solutions for the anterior segment that balance the need for functional and esthetic reconstruction. The optimal stiffness of porcelain in thin section, the ideal surface characteristics, and the biomechanical continuum achieved through high performance bonding mean the crown of the tooth as a whole can support incisal or masticatory function. By the same token, the conduction of optical effects from within the tooth combined with the ideal surface features of the porcelain veneer make this restorative approach the ultimate in esthetic satisfaction, for both the practitioner and the patient.
Lineage-specific hematopoietic growth factors.

This review surveys the mechanisms and clinical applications of three hematopoietic growth factors: erythropoietin, granulocyte colony-stimulating factor, and thrombopoietin.
Defense Mechanisms of Arthropods. XXI. Formic Acid and n-Nonyl Acetate in the Defensive Spray of Two Species of Helluomorphoides

The defensive glands of Helluomorphoides ferrugincus (LeConte) and H. latitarsis (Casey) secrete a mixture of formic acid and n -nonyl acetate. The secretion is ejected as an aimed spray. Experimental evidence indicates that the defensive effectiveness of the spray would be considerably lessened in the absence of the ester.
Effect of vasoactive intestinal peptide on the contractility of the rabbit urinary bladder.

Vasoactive intestinal peptide (V. I. P.) has been demonstrated in neuronal elements of smooth muscle organs including the urinary bladder, thus indicating that this peptide may be a neurohumoral transmitter. In isolated strips of rabbit urinary bladder we have demonstrated that V. I. P. cause relaxation. Unlike the relaxant effect of the beta agonist isoproterenol, the inhibition produced by V. I. P. could not be blocked by propranolol. These studies indicate that V. I. P. may play a role in the regulation of bladder contractility.
The use of alkoxycarbonyl derivatives for the mass spectral analysis of drug‐thioether metabolites. Studies with the cysteine, mercapturic acid and glutathione conjugates of acetaminophen

Alkoxycarbonyl derivatives of the cysteine-, N-acetylcysteine- and glutathione conjugates of acetaminophen have been prepared in aqueous buffer solutions and their chromatographic and mass spectrometric properties examined. Structurally informative fragmentation patterns of the cysteine- and N-acetylcysteine derivatives were obtained when their methyl esters were subjected to analysis by direct insertion chemical ionization (CH4) mass spectrometry, although field desorption and liquid secondary ion mass spectrometric techniques were required in order to obtain satisfactory spectral data for derivatives of the glutathione adduct. Treatment of ethoxycarbonyl derivatives of the three acetaminophen metabolites with N-methyltrifluoroacetamide-based silylating reagents led to the formation of a common volatile product which was ideally suited to analysis by gas chromatography/electron impact mass spectrometry. A mechanism is proposed for the formation of this novel derivative, which appears to possess a benzo-1,3-thioxalane structure, and its mass spectral characteristics are reported. Finally, the utility of alkoxycarbonyl derivatives for the analysis of drug—thioether conjugates in biological fluids is discussed in terms of their advantages for aqueous phase derivatization, purification by high-performance liquid chromatography and characterization by mass spectrometry.
How Shall the Stomatologist Be Educated

The question of medical education for the dentist has been under discussion for many years, and it will probably continue to be a subject of discussion for many years to come. At the first meeting of the International Association of Stomatology, held in Paris, August, 1907, that body settled to its own satisfaction these two points, first, that a complete medical education must be required of every dentist; second, that the word stomatology was defined as meaning diseases pertaining to the mouth. A stomatologist is one who treats diseases of the mouth. In consideration of these two settled principles, the following series of questions was formulated and discussion requested: "When is it best to begin the special studies; during the time of the general medical studies or immediately after these?" "Advantage and disadvantage of each." "Special studies begun during the general medical course." "Special studies begun immediately after the general
MARK/Par1 Kinase Is Activated Downstream of NMDA Receptors through a PKA-Dependent Mechanism.

The Par1 kinases, also known as microtubule affinity-regulating kinases (MARKs), are important for the establishment of cell polarity from worms to mammals. Dysregulation of these kinases has been implicated in autism, Alzheimer’s disease and cancer. Despite their important function in health and disease, it has been unclear how the activity of MARK/Par1 is regulated by signals from cell surface receptors. Here we show that MARK/Par1 is activated downstream of NMDA receptors in primary hippocampal neurons. Further, we show that this activation is dependent on protein kinase A (PKA), through the phosphorylation of Ser431 of Par4/LKB1, the major upstream kinase of MARK/Par1. Together, our data reveal a novel mechanism by which MARK/Par1 is activated at the neuronal synapse.
A case-control study of screening sigmoidoscopy and mortality from colorectal cancer.

Abstract Background The efficacy of sigmoidoscopic screening in reducing mortality from colorectal cancer remains uncertain. A randomized trial would be ideal for clarifying this issue but is very difficult to conduct. Case–control studies provide an alternative method of estimating the efficacy of screening sigmoidoscopy. Methods Using data on the 261 members of the Kaiser Permanente Medical Care Program who died of cancer of the rectum or distal colon from 1971 to 1988, we examined the use of screening by rigid sigmoidoscopy during the 10 years before the diagnosis and compared it with the use of screening in 868 control subjects matched with the case subjects for age and sex. Results Only 8.8 percent of the case subjects had undergone screening by sigmoidoscopy, as compared with 24.2 percent of the controls (matched odds ratio, 0.30; 95 percent confidence interval, 0.19 to 0.48). Adjustment for potential confounding factors increased the odds ratio to 0.41 (95 percent confidence interval, 0.25 to 0.69)...
INFLUENCE OF MOOD AND ADJUSTMENT TO CANCER ON COMPLIANCE WITH CHEMOTHERAPY AMONG BREAST CANCER PATIENTS

Abstract Approximately 75% of the 181 000 breast cancer patients newly diagnosed in 1992 will survive for at least 5 yr,but survival often depends on receiving adjuvant chemotherapy. We determined that mood variables and attitude toward cancer could predict compliance with IV-administered chemotherapy. The participants were seventy-four women diagnosed with primary breast cancer receiving treatment at a state-supported medical center in one of three southeastern metropolitan areas in the U.S. Most patients were members of minority and lower socioeconomic groups. The design was prospective in the sense that mood and attitude variables were assessed before determination of compliance. Two psychological instruments were used in this study, the Mental Adjustment to Cancer (MAC) Scale and the Affects Balance Scale (ABS). Patients who kept fewer than 85% of their appointments were classified as noncompliant; those keeping 85% or more were classified as compliant. Sixty-three percent of the patients for whom the compliance information was complete were classified as compliant; 37% were noncompliant; and four patients were not included in the analysis because their records were incomplete. The discriminant function was able to correctly classify 86% of the patients according to chemotherapy compliance, a 36% improvement over the chance level. High scores on MAC Fighting Spirit and ABS Anxiety, Depression, and Vigor scales were associated with greater adherence to a chemotherapy regimen. High scores on ABS Guilt and Hostility scales predicted lower levels of compliance.
Pacing as a treatment technique for transitional sucking patterns.

OBJECTIVE: To ascertain whether the implementation of a paced feeding protocol in a sample of preterm infants with respiratory diagnoses will result in the development of more efficient sucking patterns, increased weight gain, decreased incidence of bradycardia during feeding, and shorter length of hospital stay. METHOD: A total of 36 premature infants were enrolled into a nonrandomized clinical trial conducted in a neonatal intensive care unit (NICU). The first 18 infants were traditionally bottle-fed. Following this cohort's discharge from NICU, nursing staff completed continuing education on implementing a paced feeding protocol and the next 18 infants were delivered paced feedings. RESULTS: The two cohorts were equivalent at the initiation of oral feedings on gestational age, birth weight, 1 and 5 minute Apgar scores, weight, and postconceptual age. The paced infants demonstrated statistically and clinically significant decreases in bradycardic incidences during feeding and gains in development of more efficient sucking patterns at discharge. Discharge and average weekly weight gain did not differ between the two groups. CONCLUSIONS: The incorporation of pacing into NICU care practices appears to be beneficial for preterm infants with respiratory disease.
Demonstration of Compatible Yielding between Soil-Foundation and Superstructure Components

AbstractAlthough the nonlinear behavior of rocking shallow foundations has been experimentally and numerically demonstrated as an effective tool to dissipate vibrational energy during seismic loading, the engineering community has yet to uniformly accept it as a targeted design mechanism for diffusing seismic energy in a structure. This paper presents results of a centrifuge test program that incorporated inelastic behavior into model building systems via yielding of both structural and foundation components. Three 2-story-1-bay building models were designed with similar layouts but different combinations of foundation and structural component yield strengths and were shaken with a similar suite of earthquake motions. Measurements of behavior of each of the model buildings are presented and cross-compared in terms of time history responses, hysteretic responses of the structural and foundation fuses, and maximum response parameters. A balanced design configuration, wherein the rocking foundation and struc...